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De Faria Castro Fleury E. Why Is the Baker Classification Inadequate for Classifying Silicone Implant Fibrous Capsules? Cureus 2024; 16:e55776. [PMID: 38586672 PMCID: PMC10999057 DOI: 10.7759/cureus.55776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2024] [Indexed: 04/09/2024] Open
Abstract
Baker's clinical classification is adopted as the gold standard for grading complications related to silicone implants. Despite being widely used for this purpose, the classification has several limitations, highlighting subjectivity, reproducibility, and interobserver agreement. In this technical report, we aim to present the reasons for the inadequacy of the Baker classification for breast implants and the main factors contributing to false-negative results using recent theories of surface tension of fluids and gel bleeding. We also present an alternative classification proposal using magnetic resonance imaging of the breasts.
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Hatamleh MM, Hatamlah HM, Nuseir A. Maxillofacial prosthetics and digital technologies: Cross-sectional study of healthcare service provision, patient attitudes, and opinions. J Prosthodont 2024; 33:231-238. [PMID: 37218377 DOI: 10.1111/jopr.13718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/18/2023] [Indexed: 05/24/2023] Open
Abstract
PURPOSE Digital technologies are continuously improving the accuracy and quality of maxillofacial prosthetics, but their impact on patients remains unclear. This cross-sectional study aimed to analyze the impact of facial prosthetics service provision, patients' perception, and digital technology on prostheses construction. MATERIALS AND METHODS All patients who presented for evaluation and management of facial defects between January 2021 and December 2021 at the ENT clinic were eligible for study enrollment. Patients requiring prosthetic reconstruction of their missing facial parts were included in the study. Forty-five questionnaires were delivered, inquiring about the patients' prosthetic demographics, prosthesis manufacture using 3D technologies, and their perceptions and attitudes. RESULTS A total of 37 patients responded (29 males, eight females; mean age 20.50 years). The congenital cause was the highest among other causes (p = 0.001) with auricular defects being the highest (p = 0.001). A total of 38 prostheses were constructed and 17 prostheses were retained by 36 craniofacial implants (p = 0.014). The auricular and orbital implants success rates were 97% and 25%, respectively. The implant locations were digitally planned pre-operatively. Digital 3D technologies of defect capture, data designing, and 3D modeling were used and perceived as helpful and comfortable (p = 0.001). Patients perceived their prosthesis as easy to handle, suited them, and they felt confident with it (p = 0.001). They wore it for more than 12 h daily (p = 0.001). They were not worried that it would be noticed, and found it comfortable and stable during various activities (p = 0.001). Implant-retained prosthesis patients were more satisfied with it, and found it easy to handle and stable (p = 0.001). CONCLUSIONS Congenital defects are the main cause of facial defects in the study country. The overall acceptance of maxillofacial prostheses was good, showing high patient perception and satisfaction. Ocular and implant-retained silicone prostheses are better handled, more stable, and the latter is more satisfying than traditional adhesive prostheses. Digital technologies save time and effort invested in manufacturing facial prostheses.
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Affiliation(s)
| | - Heba Mohammad Hatamlah
- Department of Hospital Management, Faculty of Business, Philadelphia University, Amman, Jordan
| | - Amjad Nuseir
- ENT Department, Faculty of Medicine, Jordan University of Science and Technology, Irbid, Jordan
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Maciejewski B, Dłabiszewska J, Mikolaszek B, Sznitowska M. The Impact of Liquid Components on Alteration of the Adhesion of Polyacrylate and Silicone Patches. Polymers (Basel) 2023; 15:4355. [PMID: 38006080 PMCID: PMC10674843 DOI: 10.3390/polym15224355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 10/20/2023] [Accepted: 11/03/2023] [Indexed: 11/26/2023] Open
Abstract
Polyacrylates and polysiloxanes are polymers used in pressure-sensitive adhesive (PSA) patches. Liquid additives are co-solvents of the active substances or permeation enhancers, and their compatibility with the polymeric matrix and the effect on adhesive properties should be considered. The patches were prepared from commercial polyacrylates (three types of Duro-Tak®) and siloxanes (Bio-PSA® and Soft Skin Adhesive®). Propylene glycol, polyoxyethylene glycol, isopropyl myristate, triacetin, triethyl citrate and silicone oil were added (10% w/w). Formulations were evaluated microscopically and with a texture analyzer in terms of in vitro adhesiveness and hardness. Only silicone oil was compatible with the silicone matrices. The best compatibility of acrylic PSA was observed with triethyl citrate; one out of three Duro-Tak matrices was incompatible with every additive. In all compositions, the adhesiveness was impaired by the liquid additives. A significant drop in adhesiveness was noted after immersion of the patches in buffer and drying. The probe tack test was considered as the most useful for evaluation of the effect of the liquid additive on adhesiveness, but the results obtained with a spherical and cylindrical probe were contradictory. The structural changes caused by the additives were also demonstrated by a 90° peel test, considered as complementary to the tack test.
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Affiliation(s)
- Bartosz Maciejewski
- Department of Pharmaceutical Technology, Medical University of Gdańsk, Hallera Av. 107, 80-416 Gdańsk, Poland; (B.M.); (B.M.)
| | - Joanna Dłabiszewska
- Scientific Student Circle “ISPE—Industrial Pharmacy”, Medical University of Gdańsk, Hallera Av. 107, 80-416 Gdańsk, Poland
| | - Barbara Mikolaszek
- Department of Pharmaceutical Technology, Medical University of Gdańsk, Hallera Av. 107, 80-416 Gdańsk, Poland; (B.M.); (B.M.)
| | - Małgorzata Sznitowska
- Department of Pharmaceutical Technology, Medical University of Gdańsk, Hallera Av. 107, 80-416 Gdańsk, Poland; (B.M.); (B.M.)
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Simatos D, Jacobs IE, Dobryden I, Nguyen M, Savva A, Venkateshvaran D, Nikolka M, Charmet J, Spalek LJ, Gicevičius M, Zhang Y, Schweicher G, Howe DJ, Ursel S, Armitage J, Dimov IB, Kraft U, Zhang W, Alsufyani M, McCulloch I, Owens RM, Claesson PM, Knowles TPJ, Sirringhaus H. Effects of Processing-Induced Contamination on Organic Electronic Devices. Small Methods 2023; 7:e2300476. [PMID: 37661594 DOI: 10.1002/smtd.202300476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 06/28/2023] [Indexed: 09/05/2023]
Abstract
Organic semiconductors are a family of pi-conjugated compounds used in many applications, such as displays, bioelectronics, and thermoelectrics. However, their susceptibility to processing-induced contamination is not well understood. Here, it is shown that many organic electronic devices reported so far may have been unintentionally contaminated, thus affecting their performance, water uptake, and thin film properties. Nuclear magnetic resonance spectroscopy is used to detect and quantify contaminants originating from the glovebox atmosphere and common laboratory consumables used during device fabrication. Importantly, this in-depth understanding of the sources of contamination allows the establishment of clean fabrication protocols, and the fabrication of organic field effect transistors (OFETs) with improved performance and stability. This study highlights the role of unintentional contaminants in organic electronic devices, and demonstrates that certain stringent processing conditions need to be met to avoid scientific misinterpretation, ensure device reproducibility, and facilitate performance stability. The experimental procedures and conditions used herein are typical of those used by many groups in the field of solution-processed organic semiconductors. Therefore, the insights gained into the effects of contamination are likely to be broadly applicable to studies, not just of OFETs, but also of other devices based on these materials.
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Affiliation(s)
- Dimitrios Simatos
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Ian E Jacobs
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Illia Dobryden
- RISE Research Institutes of Sweden, Division of Bioeconomy and Health, Department of Material and Surface Design, RISE Research Institutes of Sweden, 11486, Stockholm, Sweden
| | - Małgorzata Nguyen
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Achilleas Savva
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, CB3 OAS, UK
| | - Deepak Venkateshvaran
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Mark Nikolka
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Jérôme Charmet
- School of Engineering-HE-Arc Ingénierie, HES-SO University of Applied Sciences Western Switzerland, 2000, Neuchâtel, Switzerland
| | - Leszek J Spalek
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Mindaugas Gicevičius
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Youcheng Zhang
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Guillaume Schweicher
- Laboratoire de Chimie des Polymères, Faculté des Sciences, Université Libre de Bruxelles (ULB), 1050, Bruxelles, Belgium
| | - Duncan J Howe
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Sarah Ursel
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | - John Armitage
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Ivan B Dimov
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, CB3 0FA, UK
| | - Ulrike Kraft
- Department of Molecular Electronics, Max Planck Institute for Polymer Research, 55128, Mainz, Germany
| | - Weimin Zhang
- Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Maryam Alsufyani
- Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK
| | - Iain McCulloch
- Physical Science and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
- Department of Chemistry, University of Oxford, Oxford, OX1 3TA, UK
| | - Róisín M Owens
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, CB3 OAS, UK
| | - Per M Claesson
- KTH Royal Institute of Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, Department of Chemistry, Division of Surface and Corrosion Science, 10044, Stockholm, Sweden
| | - Tuomas P J Knowles
- Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Henning Sirringhaus
- Optoelectronics Group, Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
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Kowalewska A, Majewska-Smolarek K. Self-Healing Antimicrobial Silicones-Mechanisms and Applications. Polymers (Basel) 2023; 15:3945. [PMID: 37835994 PMCID: PMC10575179 DOI: 10.3390/polym15193945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 09/25/2023] [Accepted: 09/26/2023] [Indexed: 10/15/2023] Open
Abstract
Organosilicon polymers (silicones) are an important part of material chemistry and a well-established commercial product segment with a wide range of applications. Silicones are of enduring interest due to their unique properties and utility. Recently, new application areas for silicone-based materials have emerged, such as stretchable electronics, wearable stress sensors, smart coatings, and soft robotics. For this reason, research interest over the past decade has been directed towards new methods of crosslinking and increasing the mechanical strength of polyorganosiloxanes. The introduction of self-healing mechanisms may be a promising alternative for such high-value materials. This approach has gained both growing research interest and a rapidly expanding range of applications. Inherent extrinsic and intrinsic self-healing methods have been used in the self-healing of silicones and have resulted in significant advances in polymer composites and coatings, including multicomponent systems. In this review, we present a summary of research work dedicated to the synthesis and applications of self-healing hybrid materials containing polysiloxane segments, with a focus on antimicrobial and antifouling coatings.
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Affiliation(s)
- Anna Kowalewska
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, Sienkiewicza 112, 90-363 Lodz, Poland;
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Kiat-amnuay S, Cevik P, Kurtoglu C. Effect of Thixotropic Agent on the Color Stability of Platinum-Based Silicone Maxillofacial Elastomers after Artificial Aging. Materials (Basel) 2023; 16:5867. [PMID: 37687559 PMCID: PMC10488689 DOI: 10.3390/ma16175867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/20/2023] [Accepted: 08/25/2023] [Indexed: 09/10/2023]
Abstract
Maxillofacial prostheses are essential for restoring natural appearance and function in individuals with defects in the head and neck regions. Thixotropic agents, as liquid additives, are known to increase the viscosity of silicone elastomers. However, color deterioration remains a challenge in facial prostheses, leading to the need for refabrication. Despite this, there is limited research on the effect of thixotropic agents on the color stability of silicone maxillofacial elastomers. This study aims to investigate the impact of different thixotropic agent amounts on the color degradation of various maxillofacial silicone elastomers. Three elastomers (A-2000, A-2006, and A-2186) were combined with five pigments (no pigment as control, red, yellow, blue, and a mixture of red, yellow, and blue), and mixed with six thixotropic agent quantities (0, 1, 2, 3, 4, and 5 drops). A total of 450 specimens were fabricated (n = 5) and aged in an artificial aging chamber. L*, a*, b* readings were obtained before and after aging using a digital spectrophotometer. Color difference (ΔE*) means and standard deviations for 150 kj/m2, 300 kj/m2, and 450 kj/m2 were calculated. Statistical analyses, including four-way ANOVA and Fisher's PLSD test, were conducted to determine any significant differences (p < 0.05) among the groups. A comprehensive analysis revealed significant four-way interactions among the groups. In the mixed-pigmentation group, adding 4 drops of thixotropic agent resulted in ΔE* above 3 only in A-2186 silicone at 300 and 450 kj/m2 energy levels. However, the color stability of mixed-pigmented A-2000 and A-2006 remained within the acceptable thresholds of 3 ΔE* at all irradiance levels in this study. At each energy level, A-2006 exhibited the highest color stability with an increasing thixotropic agent quantity among all the silicones. Conversely, A-2186 was more affected by the increased number of thixotropic agent drops in each pigmentation group, including the control group at 450 kj/m2. The quantity of thixotropic agent plays a crucial role in determining the color stability of different silicone elastomers pigmented with various intrinsic pigments. The thixotropic agent amount has a more significant impact on color stability than the type of pigment used in the silicone elastomers. A key overarching insight from this investigation is the identification of a safety threshold for the thixotropic agent quantity of 3 drops for each silicone type, pigmentation, and energy level. These findings highlight the importance of considering the proper combination of thixotropic agents, pigments, and silicone materials to achieve optimal color stability in maxillofacial prosthetic applications.
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Affiliation(s)
- Sudarat Kiat-amnuay
- Department of General Practice and Dental Public Health, School of Dentistry, The University of Texas Health Science Center at Houston, Houston, TX 77054, USA
- Houston Center for Biomaterials and Biomimetics, Houston, TX 77054, USA
| | - Pinar Cevik
- Department of General Practice and Dental Public Health, School of Dentistry, The University of Texas Health Science Center at Houston, Houston, TX 77054, USA
- Houston Center for Biomaterials and Biomimetics, Houston, TX 77054, USA
- Department of Prosthodontics, Faculty of Dentistry, Gazi University, Ankara 06490, Türkiye;
| | - Cem Kurtoglu
- Department of Prosthodontics, Faculty of Dentistry, Cukurova University, Adana 01250, Türkiye
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Ciano S, Di Mario M, Goscinny S, Van Hoeck E. Towards Less Plastic in Food Contact Materials: An In-Depth Overview of the Belgian Market. Foods 2023; 12:2737. [PMID: 37509829 PMCID: PMC10379060 DOI: 10.3390/foods12142737] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 07/14/2023] [Accepted: 07/16/2023] [Indexed: 07/30/2023] Open
Abstract
The food contact materials (FCMs) industry is forced to develop substitute materials due to constant pressure from consumers and authorities to reduce fossil-based plastic. Several alternatives are available on the market. However, market share, trends, and consumer preferences are still unclear. Therefore, this study aims to provide an overview of the Belgian FCMs market, the available substitute materials, and their uses. The market analysis was performed with an integrated web-based approach. Fifty-two sources were investigated, covering e-shops selling materials intended to replace disposable plastic materials or being advertised as environmentally friendly and websites describing homemade FCMs. The first screening identified 10,523 articles. The following data cleaning process resulted in a homogeneous dataset containing 2688 unique entries, systematically categorised into fifteen material categories and seven utilisation classes. Paper and board was the most popular material category (i.e., 37% of the entries), followed by bagasse, accounting for 9% of the entries. Takeaway and food serving (44.4% and 22.8% of the entries) were the most common usage categories. The study pursued to provide insights into current trends and consumer preferences, highlighting priorities for safety assessment and future policy making.
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Affiliation(s)
- Salvatore Ciano
- Scientific Direction "Chemical and Physical Health Risks", Sciensano, Rue Juliette Wytsman 14, 1050 Ixelles, Belgium
| | - Mélanie Di Mario
- Scientific Direction "Chemical and Physical Health Risks", Sciensano, Rue Juliette Wytsman 14, 1050 Ixelles, Belgium
| | - Séverine Goscinny
- Scientific Direction "Chemical and Physical Health Risks", Sciensano, Rue Juliette Wytsman 14, 1050 Ixelles, Belgium
| | - Els Van Hoeck
- Scientific Direction "Chemical and Physical Health Risks", Sciensano, Rue Juliette Wytsman 14, 1050 Ixelles, Belgium
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Martens E, Keupers M. Silicone-Induced Granulomas of Breast Implant Capsule (SIGBIC). J Belg Soc Radiol 2023; 107:44. [PMID: 37304908 PMCID: PMC10253231 DOI: 10.5334/jbsr.3158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 04/28/2023] [Indexed: 06/13/2023] Open
Abstract
Teaching point: A hypoechogenic mass within the fibrous capsule of a breast implant could correspond with a silicone-induced granuloma.
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Jurado CA, Alresayes S, Rojas-Rueda S, Alqahtani A, Tsujimoto A, Fischer NG, Afrashtehfar KI. Ceramic versus Composite Resin Polishing Systems on the Surface Roughness of Milled Leucite-Reinforced Ceramics. Medicina (Kaunas) 2023; 59:1048. [PMID: 37374252 DOI: 10.3390/medicina59061048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 05/26/2023] [Accepted: 05/26/2023] [Indexed: 06/29/2023]
Abstract
Background and Objective: This study aimed to compare the surface finish of milled leucite-reinforced ceramics polished with ceramic and composite polishing systems based on the manufacturers' recommendations. Materials and Methods: Sixty subtractive computer-aided manufactured (s-CAM) leucite-reinforced glass-ceramic specimens (IPS-Empress-CAD) were assigned into six groups: no polishing, a ceramic polishing kit, and four composite kit groups. The roughness average (Ra) was evaluated in microns using a profilometer, and scanning electron micrographs were obtained for qualitative analysis. A Tukey HSD posthoc test (α = 0.05) was used to determine significant intergroup differences. Results: After surface evaluation of the ceramics, the Ra values of the polishing systems ranked OptraFine (0.41 ± 0.26) < Enhance (1.60 ± 0.54) < Shofu (2.14 ± 0.44) < Astropol (4.05 ± 0.72) < DiaComp (5.66 ± 0.62) < No Polishing (5.66 ± 0.74). Discussion: Composite polishing systems did not provide as smooth surfaces as the ceramic polishing kit for CAD-CAM leucite-reinforced ceramics. Thus, using ceramic polishing systems, polishing leucite ceramics is recommended, whereas composite polishing systems should not be considered as an alternative for use in minimally invasive dentistry.
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Affiliation(s)
- Carlos A Jurado
- Department of Prosthodontics, University of Iowa College of Dentistry and Dental Clinics, Iowa City, IA 52242, USA
| | - Saad Alresayes
- Department of Prosthetic Dental Sciences, King Saud University College of Dentistry, Riyadh 11545, Saudi Arabia
| | - Silvia Rojas-Rueda
- School of Dentistry, Pontifical Xaverian University, Bogota 110231, Colombia
| | - Ali Alqahtani
- Department of Periodontics and Community Dentistry, King Khalid University College of Dentistry, Abha 62529, Saudi Arabia
| | - Akimasa Tsujimoto
- Department of Operative Dentistry, Aichi Gakuin University School of Dentistry, Nagoya 646-8650, Japan
| | - Nicholas G Fischer
- Minnesota Dental Research Center for Biomaterials and Biomechanics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Kelvin I Afrashtehfar
- Evidence-Based Practice Unit, Clinical Sciences Department, Ajman University College of Dentistry, Ajman City P.O. Box 346, United Arab Emirates
- Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, 3010 Bern, Switzerland
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Tamim K, Gale CB, Silverthorne KEC, Lu G, Iao CH, Brook MA. Antioxidant Silicone Elastomers without Covalent Cross-Links. ACS Sustain Chem Eng 2023; 11:7062-7071. [PMID: 37192891 PMCID: PMC10171216 DOI: 10.1021/acssuschemeng.3c00103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 04/11/2023] [Indexed: 05/18/2023]
Abstract
Improved sustainability is associated with elastomers that readily breakdown in the environment at end of life and, as importantly, that can be reprocessed/reused long before end of life arises. We report the preparation of silicone elastomers that possess both thermoplasticity-reprocessability-and antioxidant activity. A combination of ionic and H-bonding links natural phenolic antioxidants, including catechol, pyrogallol, tannic acid, and others, to telechelic aminoalkylsilicones. The mechanical properties of the elastomers, including their processability, are intimately linked to the ratio of [ArOH]/[H2NR] that was found to be optimal when the ratio exceeded 1:1.
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Affiliation(s)
- Khaled Tamim
- Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - Cody B. Gale
- Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - Kaitlyn E. C. Silverthorne
- Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - Guanhua Lu
- Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - Cheok Hang Iao
- Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
| | - Michael A. Brook
- Chemistry and Chemical Biology, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4M1, Canada
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Lee CU, Chin KCH, Boydston AJ. Additive Manufacturing by Heating at a Patterned Photothermal Interface. ACS Appl Mater Interfaces 2023; 15:16072-16078. [PMID: 36939689 DOI: 10.1021/acsami.3c00365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Direct additive manufacturing (AM) of commercial silicones is an unmet need with high demand. We report a new technology, heating at a patterned photothermal interface (HAPPI), which achieves AM of commercial thermoset resins without any chemical modifications. HAPPI integrates desirable aspects of stereolithography with the thermally driven chemical modalities of commercial silicone formulations. In this way, HAPPI combines the geometric advantages of vat photopolymerization with the materials properties of, for example, injection molded silicones. We describe the realization of the new technology, HAPPI printing using a commercial Sylgard 184 polydimethylsiloxane resin, comparative analyses of material properties, and demonstration of HAPPI in targeted applications.
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Affiliation(s)
- Chang-Uk Lee
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Kyle C H Chin
- Department of Chemical and Biological Engineering, University of Wisconsin, Madison, Wisconsin 53706, United States
| | - Andrew J Boydston
- Department of Chemistry, University of Wisconsin, Madison, Wisconsin 53706, United States
- Department of Chemical and Biological Engineering, University of Wisconsin, Madison, Wisconsin 53706, United States
- Department of Materials Science and Engineering, University of Wisconsin, Madison, Wisconsin 53706, United States
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Osorio LFF, Maciel CFE, Gallo CBM, Sampaio FJ. Evaluation of laparoscopic knot training in a silicone model. Rev Col Bras Cir 2023; 50:e20233476. [PMID: 36921135 PMCID: PMC10519689 DOI: 10.1590/0100-6991e-20233476-en] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 10/22/2022] [Indexed: 03/18/2023] Open
Abstract
INTRODUCTION in videolaparoscopic surgery, movements are conducted from a twenty times magnified image of an indirect operative field. The video interface used assumes the need for depth perception using two dimensions instead of three. OBJECTIVE to evaluate the effectiveness of training to perform the laparoscopic knot in a silicone model, in 8-hour courses, and to analyze the correlation of learning outcomes with factors such as: sex, age, laterality, previous knowledge in endosuture and medical specialty. MATERIAL AND METHODS in this prospective and randomized study, 56 students were evaluated, who took 8-hour courses, with groups of up to ten students. We used: a white box with camera, LCD screen and silicone piece. Four exercises were performed on the silicone mold: right hand, left hand, needle at 45° and back hand. RESULTS 56 students (mean age = 33.28 years). The female group, n=18, mean age 29.61 years, 17 right-handed and 1 left-handed. The male group, n=38, mean age 34.57 years, 35 right-handers, 1 left-handed and 2 ambidextrous. In both groups, no correlation was observed between the analyzes of well performed knots when correlated with the age or sex of the participants. CONCLUSION laparoscopic knot training, in silicone molds, in 8 h courses, proved to be effective. Factors such as gender, age, laterality, previous knowledge in endosuture and medical specialty do not interfere with the learning results.
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Affiliation(s)
- Luiz Felipe Fernandes Osorio
- - Universidade do Estado do Rio de Janeiro, Unidade de Pesquisa Urogenital - Programa de Pós-Graduação em Fisiopatologia e Ciências Cirúrgicas - Rio de Janeiro - RJ - Brasil
| | - Clarice Fraga Esteves Maciel
- - Universidade do Estado do Rio de Janeiro, Unidade de Pesquisa Urogenital - Programa de Pós-Graduação em Fisiopatologia e Ciências Cirúrgicas - Rio de Janeiro - RJ - Brasil
| | - Carla Braga Mano Gallo
- - Universidade do Estado do Rio de Janeiro, Unidade de Pesquisa Urogenital - Programa de Pós-Graduação em Fisiopatologia e Ciências Cirúrgicas - Rio de Janeiro - RJ - Brasil
| | - Francisco J Sampaio
- - Universidade do Estado do Rio de Janeiro, Unidade de Pesquisa Urogenital - Programa de Pós-Graduação em Fisiopatologia e Ciências Cirúrgicas - Rio de Janeiro - RJ - Brasil
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13
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Erlenbach S, Mondal K, Ma J, Neumann TV, Ma S, Holbery JD, Dickey MD. Flexible-to-Stretchable Mechanical and Electrical Interconnects. ACS Appl Mater Interfaces 2023; 15:6005-6012. [PMID: 36599089 DOI: 10.1021/acsami.2c14260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Stretchable electronic devices that maintain electrical function when subjected to stress or strain are useful for enabling new applications for electronics, such as wearable devices, human-machine interfaces, and components for soft robotics. Powering and communicating with these devices is a challenge. NFC (near-field communication) coils solve this challenge but only work efficiently when they are in close proximity to the device. Alternatively, electrical signals and power can arrive via physical connections between the stretchable device and an external source, such as a battery. The ability to create a robust physical and electrical connection between mechanically disparate components may enable new types of hybrid devices in which at least a portion is stretchable or deformable, such as hinges. This paper presents a simple method to make mechanical and electrical connections between elastomeric conductors and flexible (or rigid) conductors. The adhesion at the interface between these disparate materials arises from surface chemistry that forms strong covalent bonds. The utilization of liquid metals as the conductor provides stretchable interconnects between stretchable and non-stretchable electrical traces. The liquid metal can be printed or injected into vias to create interconnects. We characterized the mechanical and electrical properties of these hybrid devices to demonstrate the concept and identify geometric design criteria to maximize mechanical strength. The work here provides a simple and general strategy for creating mechanical and electrical connections that may find use in a variety of stretchable and soft electronic devices.
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Affiliation(s)
- Steven Erlenbach
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695, United States
| | - Kunal Mondal
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695, United States
| | - Jinwoo Ma
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695, United States
| | - Taylor V Neumann
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695, United States
| | - Siyuan Ma
- Applied Sciences Group, Microsoft Corporation, Redmond, Washington 98052, United States
| | - James D Holbery
- Applied Sciences Group, Microsoft Corporation, Redmond, Washington 98052, United States
| | - Michael D Dickey
- Department of Chemical and Biomolecular Engineering, North Carolina State University, 911 Partners Way, Raleigh, North Carolina 27695, United States
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14
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Li Z, Wang X, Bai H, Cao M. Advances in Bioinspired Superhydrophobic Surfaces Made from Silicones: Fabrication and Application. Polymers (Basel) 2023; 15:polym15030543. [PMID: 36771848 PMCID: PMC9919805 DOI: 10.3390/polym15030543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/12/2023] [Accepted: 01/16/2023] [Indexed: 01/24/2023] Open
Abstract
As research on superhydrophobic materials inspired by the self-cleaning and water-repellent properties of plants and animals in nature continues, the superhydrophobic preparation methods and the applications of superhydrophobic surfaces are widely reported. Silicones are preferred for the preparation of superhydrophobic materials because of their inherent hydrophobicity and strong processing ability. In the preparation of superhydrophobic materials, silicones can both form micro-/nano-structures with dehydration condensation and reduce the surface energy of the material surface because of their intrinsic hydrophobicity. The superhydrophobic layers of silicone substrates are characterized by simple and fast reactions, high-temperature resistance, UV resistance, and anti-aging. Although silicone superhydrophobic materials have the disadvantages of relatively low mechanical stability, this can be improved by the rational design of the material structure. Herein, we summarize the superhydrophobic surfaces made from silicone substrates, including the cross-linking processes of silicones through dehydration condensation and hydrosilation, and the surface hydrophobic modification by grafting hydrophobic silicones. The applications of silicone-based superhydrophobic surfaces have been introduced such as self-cleaning, corrosion resistance, oil-water separation, etc. This review article should provide an overview to the bioinspired superhydrophobic surfaces of silicone-based materials, and serve as inspiration for the development of polymer interfaces and colloid science.
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Affiliation(s)
- Zhe Li
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
| | - Xinsheng Wang
- School of Materials Science and Engineering, Smart Sensing Interdisciplinary Science Center, Nankai University, Tianjin 300350, China
| | - Haoyu Bai
- School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China
- School of Materials Science and Engineering, Smart Sensing Interdisciplinary Science Center, Nankai University, Tianjin 300350, China
| | - Moyuan Cao
- School of Materials Science and Engineering, Smart Sensing Interdisciplinary Science Center, Nankai University, Tianjin 300350, China
- Correspondence:
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15
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Praveen S, Kim T, Jung SP, Lee CW. 3D-Printed Silicone Substrates as Highly Deformable Electrodes for Stretchable Li-Ion Batteries. Small 2023; 19:e2205817. [PMID: 36408809 DOI: 10.1002/smll.202205817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/04/2022] [Indexed: 06/16/2023]
Abstract
Stretchable energy storage devices receive a considerable attention at present due to their growing demand for powering wearable electronics. A vital component in stretchable energy storage devices is its electrode which should endure a large and repeated number of mechanical deformations during its prolonged use. It is crucial to develop a technology to fabricate highly deformable electrode in an easy and an economic manner. Here, the fabrication of stretchable electrode substrates using 3D-printing technology is reported. The ink for fabricating it contains a mixture of sacrificial sugar particles and polydimethylsiloxane resin which solidifies upon thermal curing. The printed stretchable substrate attains a porous structure after leaching the sugar particles in water. The resulting printed porous stretchable substrates are then utilized as electrodes for Li-ion batteries (LIBs) after loading them with electrode materials. The batteries with stretchable electrodes exhibit a decent electrochemical performance comparable to that of the conventional electrodes. The stretchable electrodes also exhibit a stable electrochemical performance under various mechanical deformations and even after several hundreds of stretch/release cycles. This work provides a feasible route for constructing LIBs with high stretchability and enhanced electrochemical performance thereby providing a platform for realizing stretchable batteries for next generation wearable electronics.
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Affiliation(s)
- Sekar Praveen
- Department of Chemical Engineering (Integrated Engineering), College of Engineering, Kyung Hee University, 1732 Deogyeong-daero, Giheung, Yongin, Gyeonggi, 17104, South Korea
| | - Taehyung Kim
- Department of Chemical Engineering (Integrated Engineering), College of Engineering, Kyung Hee University, 1732 Deogyeong-daero, Giheung, Yongin, Gyeonggi, 17104, South Korea
| | - Soon Phil Jung
- Department of Chemical Engineering (Integrated Engineering), College of Engineering, Kyung Hee University, 1732 Deogyeong-daero, Giheung, Yongin, Gyeonggi, 17104, South Korea
| | - Chang Woo Lee
- Department of Chemical Engineering (Integrated Engineering), College of Engineering, Kyung Hee University, 1732 Deogyeong-daero, Giheung, Yongin, Gyeonggi, 17104, South Korea
- Center for the SMART Energy Platform, College of Engineering, Kyung Hee University, 1732 Deogyeong-daero, Giheung, Yongin, Gyeonggi, 17104, South Korea
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16
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Mikolaszek B, Jamrógiewicz M, Mojsiewicz-Pieńkowska K, Sznitowska M. Microscopic and Spectroscopic Imaging and Thermal Analysis of Acrylates, Silicones and Active Pharmaceutical Ingredients in Adhesive Transdermal Patches. Polymers (Basel) 2022; 14:polym14142888. [PMID: 35890664 PMCID: PMC9322838 DOI: 10.3390/polym14142888] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 07/04/2022] [Accepted: 07/05/2022] [Indexed: 02/04/2023] Open
Abstract
Dermal or transdermal patches are increasingly becoming a noteworthy alternative as carriers for active pharmaceutical ingredients (APIs), which makes their detailed physicochemical evaluation essential for pharmaceutical development. This paper demonstrates mid-infrared (FTIR) and Raman spectroscopy with complementary microscopic methods (SEM, optical and confocal Raman microscopy) and differential scanning calorimetry (DSC) as tools for the identification of the state of model API (testosterone TST, cytisine CYT or indomethacin IND) in selected adhesive matrices. Among the employed spectroscopic techniques, FTIR and Raman may be used not only as standard methods for API identification in the matrix, but also as a means of distinguishing commercially available polymeric materials of a similar chemical structures. A novel approach for the preparation of adhesive polymers for the FTIR analysis was introduced. In silicone matrices, all three APIs were suspended, whereas in the case of the acrylic PSA, Raman microscopy confirmed that only IND was dissolved in all three acrylic matrices, and the dissolved fraction of the CYT differed depending on the matrix type. Moreover, the recrystallization of TST was observed in one of the acrylates. Interestingly, a DSC analysis of the acrylic patches did not confirm the presence of the API even if the microscopic images showed suspended particles.
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Affiliation(s)
- Barbara Mikolaszek
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Medical University of Gdańsk, 80-416 Gdańsk, Poland;
| | - Marzena Jamrógiewicz
- Department of Physical Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, 80-416 Gdańsk, Poland; (M.J.); (K.M.-P.)
| | - Krystyna Mojsiewicz-Pieńkowska
- Department of Physical Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, 80-416 Gdańsk, Poland; (M.J.); (K.M.-P.)
| | - Małgorzata Sznitowska
- Department of Pharmaceutical Technology, Faculty of Pharmacy, Medical University of Gdańsk, 80-416 Gdańsk, Poland;
- Correspondence: ; Tel.: +48-58-349-1080; Fax: +48-58-349-1090
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17
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van der Pluijm RW, W Haak B, Kers J, L Siegenbeek van Heukelom T, van Vugt M. Immune reconstitution inflammatory syndrome induced by gluteal silicones in a transgender woman living with HIV. Int J STD AIDS 2022; 33:625-627. [PMID: 35343334 DOI: 10.1177/09564624221086853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We report a case of an immune reconstitution inflammatory syndrome induced by gluteal silicones in a transgender woman living with HIV following the start of antiretroviral therapy. This case resembles the autoimmune/inflammatory syndrome induced by adjuvants (ASIA) syndrome that has been described as a complication of insertions of materials such as injected or implanted silicones. The potential of developing an inflammatory response in patient with injected or implanted silicones/foreign substances should be considered in patients who have recently started antiretroviral therapy.
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Affiliation(s)
- Rob W van der Pluijm
- Department of Medicine, Division of Infectious Diseases, 26066Amsterdam UMC, Location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Bastiaan W Haak
- Department of Medicine, Division of Infectious Diseases, 26066Amsterdam UMC, Location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Jesper Kers
- Department of Pathology, 26066Amsterdam UMC, Location AMC, University of Amsterdam, Amsterdam, The Netherlands
| | | | - Michele van Vugt
- Department of Medicine, Division of Infectious Diseases, 26066Amsterdam UMC, Location AMC, University of Amsterdam, Amsterdam, The Netherlands
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18
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Fleury EDFC. Tumor Remnant After Silicone Implant En Bloc Capsulectomy: The Magnetic Resonance Role. Clin Anat 2022; 35:679-681. [PMID: 35442548 DOI: 10.1002/ca.23891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 04/10/2022] [Accepted: 04/18/2022] [Indexed: 11/05/2022]
Abstract
Recently, there has been an increase in surgeries to treat silicones implant complications. These procedures are generally related to diseased fibrous capsules, with capsular contracture the most common clinical manifestation. However, patients often do not undergo a magnetic resonance imaging (MRI) scan for the explant surgical programming to access the fibrous capsule status and avoid residual diseased tissue. The accuracy of MRI to assess fibrous capsule breast neoplasm remnants depends on the surgical time. The ideal time for the evaluation is up to 72 hours after the surgery when the repaired tissue starts to appear. Up to 2-3 weeks after surgery, MRI can provide information on the presence of a residual tumor. After this period, the presence of scar tissue and granuloma impairs the analysis. This communication discusses the role of MRI in evaluating residual fibrous capsules in the postoperative period. This article is protected by copyright. All rights reserved.
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19
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Wezgowiec J, Wieczynska A, Wieckiewicz M, Czarny A, Malysa A, Seweryn P, Zietek M, Paradowska-Stolarz A. Evaluation of Antimicrobial Efficacy of UVC Radiation, Gaseous Ozone, and Liquid Chemicals Used for Disinfection of Silicone Dental Impression Materials. Materials (Basel) 2022; 15:ma15072553. [PMID: 35407884 PMCID: PMC8999620 DOI: 10.3390/ma15072553] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 03/24/2022] [Accepted: 03/28/2022] [Indexed: 02/02/2023]
Abstract
Effective disinfection of dental impressions is an indispensable requirement for the safety of dental personnel and patients. The ideal method should be not only effective but also convenient, cheap, and environmentally friendly. This study aimed to reliably evaluate the efficacy of ultraviolet C (UVC) radiation, gaseous ozone, and commercial liquid chemicals used for silicone dental impressions disinfection. These methods were applied to two types of elastomeric impression materials: condensation silicones and addition silicones of various consistency (putty, medium, and light). The antimicrobial effectiveness against Pseudomonas aeruginosa, Staphylococcus aureus, and Candida albicans was evaluated in vitro by counting colony-forming units (CFU) on the surface of samples. The one-way ANOVA with a Tukey HSD test or the Kruskal–Wallis with a Dunn’s test was performed. The results obtained revealed the efficacy of the proposed methods for disinfection of both C-silicones and A-silicones in most of the studied groups. Only one material (Panasil initial contact Light) was not effectively disinfected after UVC irradiation or ozone application. In conclusion, the potential of each disinfection method should be evaluated separately for each material. Moreover, in further research, the possible influence of the proposed methods on the physical properties of the impression materials should be thoroughly investigated.
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Affiliation(s)
- Joanna Wezgowiec
- Department of Experimental Dentistry, Wroclaw Medical University, 50-425 Wroclaw, Poland; (J.W.); (A.M.); (P.S.); (M.Z.)
| | - Anna Wieczynska
- Department of Physicochemistry of Microorganisms, Institute of Genetics and Microbiology, University of Wroclaw, Przybyszewskiego 63/77, 51-148 Wroclaw, Poland;
- Department of Engineering and Technology of Chemical Processes, Faculty of Chemistry, Wroclaw University of Science and Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland
| | - Mieszko Wieckiewicz
- Department of Experimental Dentistry, Wroclaw Medical University, 50-425 Wroclaw, Poland; (J.W.); (A.M.); (P.S.); (M.Z.)
- Correspondence: (M.W.); (A.P.-S.)
| | - Anna Czarny
- Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 12 R. Weigl St., 53-114 Wroclaw, Poland;
| | - Andrzej Malysa
- Department of Experimental Dentistry, Wroclaw Medical University, 50-425 Wroclaw, Poland; (J.W.); (A.M.); (P.S.); (M.Z.)
| | - Piotr Seweryn
- Department of Experimental Dentistry, Wroclaw Medical University, 50-425 Wroclaw, Poland; (J.W.); (A.M.); (P.S.); (M.Z.)
| | - Marek Zietek
- Department of Experimental Dentistry, Wroclaw Medical University, 50-425 Wroclaw, Poland; (J.W.); (A.M.); (P.S.); (M.Z.)
| | - Anna Paradowska-Stolarz
- Division of Dentofacial Anomalies, Department of Maxillofacial Orthopedics and Orthodontics, Wroclaw Medical University, 50-425 Wroclaw, Poland
- Correspondence: (M.W.); (A.P.-S.)
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20
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Dasan A, Kraxner J, Grigolato L, Savio G, Elsayed H, Galusek D, Bernardo E. 3D Printing of Hierarchically Porous Lattice Structures Based on Åkermanite Glass Microspheres and Reactive Silicone Binder. J Funct Biomater 2022; 13:8. [PMID: 35076529 PMCID: PMC8788511 DOI: 10.3390/jfb13010008] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 01/07/2022] [Accepted: 01/11/2022] [Indexed: 02/06/2023] Open
Abstract
The present study illustrates the manufacturing method of hierarchically porous 3D scaffolds based on åkermanite as a promising bioceramic for stereolithography. The macroporosity was designed by implementing 3D models corresponding to different lattice structures (cubic, diamond, Kelvin, and Kagome). To obtain micro-scale porosity, flame synthesized glass microbeads with 10 wt% of silicone resins were utilized to fabricate green scaffolds, later converted into targeted bioceramic phase by firing at 1100 °C in air. No chemical reaction between the glass microspheres, crystallizing into åkermanite, and silica deriving from silicone oxidation was observed upon heat treatment. Silica acted as a binder between the adjacent microspheres, enhancing the creation of microporosity, as documented by XRD, and SEM coupled with EDX analysis. The formation of 'spongy' struts was confirmed by infiltration with Rhodamine B solution. The compressive strength of the sintered porous scaffolds was up to 0.7 MPa with the porosity of 68-84%.
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Affiliation(s)
- Arish Dasan
- Centre for Functional and Surface-Functionalized Glass, Alexander Dubček University of Trenčín, 911 50 Trenčín, Slovakia; (J.K.); (D.G.)
- Department of Industrial Engineering, Università degli Studi di Padova, 35131 Padova, Italy; (L.G.); (H.E.)
- Department of Civil, Environmental and Architectural Engineering (ICEA), University of Padova, 35131 Padova, Italy;
| | - Jozef Kraxner
- Centre for Functional and Surface-Functionalized Glass, Alexander Dubček University of Trenčín, 911 50 Trenčín, Slovakia; (J.K.); (D.G.)
| | - Luca Grigolato
- Department of Industrial Engineering, Università degli Studi di Padova, 35131 Padova, Italy; (L.G.); (H.E.)
- Department of Civil, Environmental and Architectural Engineering (ICEA), University of Padova, 35131 Padova, Italy;
| | - Gianpaolo Savio
- Department of Civil, Environmental and Architectural Engineering (ICEA), University of Padova, 35131 Padova, Italy;
| | - Hamada Elsayed
- Department of Industrial Engineering, Università degli Studi di Padova, 35131 Padova, Italy; (L.G.); (H.E.)
- Refractories, Ceramics and Building Materials Department, National Research Centre, El Buhouth Str., Cairo 12622, Egypt
| | - Dušan Galusek
- Centre for Functional and Surface-Functionalized Glass, Alexander Dubček University of Trenčín, 911 50 Trenčín, Slovakia; (J.K.); (D.G.)
- Joint Glass Centre of the IIC SAS, TnUAD, and FChFT STU, FunGlass, Alexander Dubček University of Trenčín, 911 50 Trenčín, Slovakia
| | - Enrico Bernardo
- Department of Industrial Engineering, Università degli Studi di Padova, 35131 Padova, Italy; (L.G.); (H.E.)
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21
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Matthews JC. A mechanistic evaluation of the potential for octamethylcyclotetrasiloxane to produce effects via endocrine modes of action. Crit Rev Toxicol 2021; 51:571-590. [PMID: 34877914 DOI: 10.1080/10408444.2021.1994525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
This review is a hypothesis driven, mechanistic evaluation of the potential for octamethylcyclotetrasiloxane (D4) to produce any effects via endocrine modes of action. D4 is a volatile, lipophilic liquid used in the production of high molecular weight dimethylsiloxane polymers. These are used in a variety of industrial, medical, cleaning, and personal care products, and they may contain low levels of residual D4. Low concentrations of D4 are found in the environment and there is potential for low level human exposure. All of the measured environmental and workplace levels of D4 fall below no observed effect levels (NOEL). Most of the effects of high dose D4 involve the female reproductive system. In the mature intact female rat following chronic high dose exposure, D4 may cause inhibition of mating and ovulation, decreased live litter sizes, small increases in the estrogen to progesterone ratio primarily through decreases in progesterone, and increases in uterine hyperplasia. When endogenous estrogens are very low, high dose D4 causes increases in some uterine parameters. To assess whether these high dose effects can be attributed to an endocrine mode of action, endpoints are ranked for relevance and strength, consistent with published concepts. When sufficient information is available the level of activity of D4 for producing the observed effect is compared with that of potent endocrines. The conclusions reached are that all of the effects of D4 fall well short of any established criteria for D4 to be capable of producing any adverse effect via an endocrine mode of action.
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Affiliation(s)
- John C Matthews
- Department of Biomolecular Sciences, University of Mississippi School of Pharmacy, University, MS, USA
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22
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Halvey AK, Macdonald B, Golovin K, Boban M, Dhyani A, Lee DH, Gose JW, Ceccio SL, Tuteja A. Rapid and Robust Surface Treatment for Simultaneous Solid and Liquid Repellency. ACS Appl Mater Interfaces 2021; 13:53171-53180. [PMID: 34709778 DOI: 10.1021/acsami.1c14174] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
A wide range of liquid and solid contaminants can adhere to everyday functional surfaces and dramatically alter their performance. Numerous surface modification strategies have been developed that can reduce the fouling of some solids or repel certain liquids but are generally limited to specific contaminants or class of foulants. This is due to the typically distinct mechanisms that are employed to repel liquids vs solids. Here, we demonstrate a rapid and facile surface modification technique that yields a thin film of linear chain siloxane molecules covalently tethered to a surface. We investigate and characterize the liquid-like morphology of these surfaces in detail as the key contributing factor to their anti-fouling performance. This surface treatment is extremely durable and readily repels a broad range of liquids with varying surface tensions and polarities, including water, oils, organic solvents, and even fluorinated solvents. Additionally, the flexible, liquid-like nature of these surfaces enables interfacial slippage, which dramatically reduces adhesion to various types of solids, including ice, wax, calcined gypsum, and cyanoacrylate adhesives, and also minimizes the nucleation of inorganic scale. The developed surfaces are durable and simple to fabricate, and they minimize fouling by both liquids and solids simultaneously.
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Affiliation(s)
- Alex Kate Halvey
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Biointerfaces Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Brian Macdonald
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Biointerfaces Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Kevin Golovin
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Biointerfaces Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Mathew Boban
- Department of Macromolecular Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Biointerfaces Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Abhishek Dhyani
- Department of Macromolecular Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Biointerfaces Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Duck Hyun Lee
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Biointerfaces Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - James W Gose
- Department of Naval Architecture and Marine Engineering, University of Michigan, Ann Arbor 48109, Michigan, United States
| | - Steven L Ceccio
- Department of Naval Architecture and Marine Engineering, University of Michigan, Ann Arbor 48109, Michigan, United States
| | - Anish Tuteja
- Department of Materials Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Macromolecular Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
- Department of Chemical Engineering, University of Michigan, Ann Arbor 48109, Michigan, United States
- Biointerfaces Institute, University of Michigan, Ann Arbor, Michigan 48109, United States
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23
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Tyukanko V, Demyanenko A, Dyuryagina A, Ostrovnoy K, Lezhneva M. Optimization of the Composition of Silicone Enamel by the Taguchi Method Using Surfactants Obtained from Oil Refining Waste. Polymers (Basel) 2021; 13:polym13213619. [PMID: 34771180 PMCID: PMC8587935 DOI: 10.3390/polym13213619] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 10/11/2021] [Accepted: 10/18/2021] [Indexed: 11/20/2022] Open
Abstract
The aim of this work is to optimize the composition of a two-component silicone enamel consisting of an aluminum pigment and a polyphenylsiloxane polymer to obtain the maximum dispersion of the pigment in the coating. The following products were used as surfactants: AS-1, PEPA, and Telaz. To assess the effect of surfactants on the dispersion of the pigment, computer-optical microscopy was used. The results of the studies showed that all the studied surfactants cause an improvement in the dispersion of the pigment. According to the degree of influence on the dispersion of the pigment, surfactants can be arranged in a row: PEPA > Telaz > AS-1. When the PEPA content in the enamel is 0.25 g/dm3, a decrease in the diameter of the pigment particles by 46% (from 26 to 14 microns) is recorded, with an increase in their specific amount by 2 times (from 258 to 550 pcs). Optimal enamel compositions allow a reduction in the corrosion rate by 11 times (from 0.6 to 0.053 mm/year) and improvement to the decorative properties of coatings (roughness, gloss, etc.). The effectiveness of the AS-1 product (obtained from oil refining waste) as a dispersant additive in silicone enamel has been proven.
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Samaran Q, Bekara F, Aljaber F, Clark E, Dereure O, Raison-Peyron N. An immune reaction caused by silicone breast implants. Contact Dermatitis 2021; 85:703-705. [PMID: 34250621 DOI: 10.1111/cod.13936] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 07/09/2021] [Indexed: 11/29/2022]
Affiliation(s)
- Quentin Samaran
- Department of Dermatology, University of Montpellier, Montpellier, France
| | - Farid Bekara
- Department of Plastic and Reconstructive Surgery, Burns and Wound Healing Units, CHRU Lapeyronie, Montpellier University Hospital and Montpellier University, Montpellier, France
| | - Faisal Aljaber
- Department of Dermatology, University of Montpellier, Montpellier, France
| | - Evangéline Clark
- Department of Dermatology, University of Montpellier, Montpellier, France
| | - Olivier Dereure
- Department of Dermatology, University of Montpellier, Montpellier, France
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Cazacu M, Racles C, Zaltariov MF, Dascalu M, Bele A, Tugui C, Bargan A, Stiubianu G. From Amorphous Silicones to Si-Containing Highly Ordered Polymers: Some Romanian Contributions in the Field. Polymers (Basel) 2021; 13:polym13101605. [PMID: 34065717 PMCID: PMC8157024 DOI: 10.3390/polym13101605] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/12/2021] [Accepted: 05/12/2021] [Indexed: 11/16/2022] Open
Abstract
Polydimethylsiloxane (PDMS), in spite of its well-defined helical structure, is an amorphous fluid even at extremely high molecular weights. The cause of this behavior is the high flexibility of the siloxane backbone and the lack of intermolecular interactions attributed to the presence of methyl groups. These make PDMS incompatible with almost any organic or inorganic component leading to phase separation in siloxane-siloxane copolymers containing blocks with polar organic groups and in siloxane-organic copolymers, where dimethylsiloxane segments co-exist with organic ones. Self-assembly at the micro- or nanometric scale is common in certain mixed structures, including micelles, vesicles, et cetera, manifesting reversibly in response to an external stimulus. Polymers with a very high degree of ordering in the form of high-quality crystals were obtained when siloxane/silane segments co-exist with coordinated metal blocks in the polymer chain. While in the case of coordination of secondary building units (SBUs) with siloxane ligands 1D chains are formed; when coordination is achieved in the presence of a mixture of ligands, siloxane and organic, 2D structures are formed in most cases. The Romanian research group's results regarding these aspects are reviewed: from the synthesis of classic, amorphous silicone products, to their adaptation for use in emerging fields and to new self-assembled or highly ordered structures with properties that create perspectives for the use of silicones in hitherto unexpected areas.
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Affiliation(s)
- Maria Cazacu
- Correspondence: ; Tel.: +40-232-217-454; Fax: +40-232-211-299
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26
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Ault CA, Beach J, Mann S, Wan X, Zlatanic A, Patterson S, Messman JM, Dvornic PR. Effect of Molecular Weight of Methylphenylsiloxy-Containing Vinyl-Functionalized Terpolysiloxanes on Their UV-Activated Crosslinking by Hydrosilylation and Mechanical Properties of Crosslinked Elastomers. Macromol Rapid Commun 2021; 42:e2000692. [PMID: 33502036 DOI: 10.1002/marc.202000692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/16/2020] [Indexed: 11/09/2022]
Abstract
Effects of molecular weight of methylphenyl-containing vinylsiloxy-functionalized terpolysiloxanes on their UV-activated crosslinking by hydrosilylation at room temperature in air, shelf life stability of "all-in-one" pastes prepared from them for additive manufacturing, and mechanical properties of the resulting crosslinked elastomers, are investigated. It is found that while rheology of pastes containing base polymers, trimethylsilylated silica fillers, and thixotropic additives is not significantly affected by the base polymer molecular weight but is dominated by the filler concentration, the pastes based on higher molecular weight polymers exhibit faster crosslinking (corresponding to higher catalyst turnover numbers) and their crosslinked elastomers show transient strain-induced crystallization. The latter appears in networks from terpolymers with degrees of polymerization (DP) of 240 and above (corresponding to about one half of the critical polydimethylsiloxane chain length for entanglement formation of DP = 460), within the temperature range of -80 to -30 °C, characteristic for polydimethylsiloxane melting transition. It is believed that this is the first time an observation of this chain length effect is reported for polysiloxane elastomers and that the properties reported herein can be expected to have major implications on the application potential of these polymers in both additive manufacturing and performance of their elastomers at sub-ambient temperatures.
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Affiliation(s)
- Charles A Ault
- C. A. Ault, J. Beach, X. Wan, A. Zlatanic [+], Kansas Polymer Research Center, Pittsburg State University, Pittsburg, KS, 66762, USA
| | - James Beach
- C. A. Ault, J. Beach, X. Wan, A. Zlatanic [+], Kansas Polymer Research Center, Pittsburg State University, Pittsburg, KS, 66762, USA
| | - Shane Mann
- Department of Chemistry, Pittsburg State University, Pittsburg, KS, 66762, USA
| | - Xianmei Wan
- C. A. Ault, J. Beach, X. Wan, A. Zlatanic [+], Kansas Polymer Research Center, Pittsburg State University, Pittsburg, KS, 66762, USA
| | - Alisa Zlatanic
- C. A. Ault, J. Beach, X. Wan, A. Zlatanic [+], Kansas Polymer Research Center, Pittsburg State University, Pittsburg, KS, 66762, USA
| | - Steven Patterson
- Honeywell Federal Manufacturing and Technologies LLC, Kansas City, MO, 64147, USA
| | - Jamie M Messman
- Honeywell Federal Manufacturing and Technologies LLC, Kansas City, MO, 64147, USA
| | - Petar R Dvornic
- Department of Chemistry, Pittsburg State University, Pittsburg, KS, 66762, USA
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Bian P, Wang Y, McCarthy TJ. Rediscovering Silicones: The Anomalous Water Permeability of "Hydrophobic" PDMS Suggests Nanostructure and Applications in Water Purification and Anti-Icing. Macromol Rapid Commun 2020; 42:e2000682. [PMID: 33368751 DOI: 10.1002/marc.202000682] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/07/2020] [Indexed: 12/19/2022]
Abstract
Cross-linked polydimethylsiloxane (PDMS) is simultaneously water-repellent and highly permeable to water vapor. Unfilled and silica-free cross-linked PDMS films of variable thickness (8-160 µm) are prepared and their water vapor transmission rates and permeability values are determined. Vapor transmission rate increases as membrane thickness decreased from 160 to 15 µm, but does not increase further when the film thickness is decreased to 8 µm. Rate-limiting sorption is implicated as the cause of this effect and substantiated by a surface modification to enhance adsorption rate. Water vapor does not macroscopically condense on films thin enough to operate in this kinetic regime, and vapor transmission rates as high as 60% of the transmission rates through air are measured. A mechanism for water permeation is offered based on those proposed for nanoscopically confined water in carbon nanotubes and aquaporins.
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Affiliation(s)
- Pei Bian
- Polymer Science and Engineering Department, University of Massachusetts, Amherst, MA, 01003, USA
| | - Yan Wang
- Polymer Science and Engineering Department, University of Massachusetts, Amherst, MA, 01003, USA
| | - Thomas J McCarthy
- Polymer Science and Engineering Department, University of Massachusetts, Amherst, MA, 01003, USA
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Lasowski F, Rambarran T, Rahmani V, Brook MA, Sheardown H. PEG-containing siloxane materials by metal-free click-chemistry for ocular drug delivery applications. J Biomater Sci Polym Ed 2020; 32:581-594. [PMID: 33187457 DOI: 10.1080/09205063.2020.1851558] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Metal-free click-chemistry can be used to create silicone hydrogels for ocular drug delivery applications, imparting the benefits of silicones without catalyst contamination. Previous work has demonstrated the capacity for these materials to significantly reduce protein adsorption. Building upon this success, the current work examines and optimizes different materials in terms of their protein adsorption and drug release capabilities. Specifically, incorporating lower molecular weight poly-ethylene glycol (PEG) is better able to reduce protein adsorption. However, with higher molecular weight PEG, the materials exhibit excellent water content and better drug release profiles. The lower molecular weight PEG is also able to deliver the drug over a period in excess of four months, with the amount of crosslinking having the greatest impact on the amount of drug release. Overall, these materials show great promise for ocular applications.
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Affiliation(s)
- Frances Lasowski
- Department of Chemical Engineering, McMaster University, Hamilton, ON, Canada
| | - Talena Rambarran
- Department of Chemical Engineering, McMaster University, Hamilton, ON, Canada
| | - Vida Rahmani
- Department of Chemical Engineering, McMaster University, Hamilton, ON, Canada
| | - Michael A Brook
- Department of Chemistry and Chemical Biology, McMaster University, Hamilton, ON, Canada
| | - Heather Sheardown
- Department of Chemical Engineering, McMaster University, Hamilton, ON, Canada
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Francis A. Biological evaluation of preceramic organosilicon polymers for various healthcare and biomedical engineering applications: A review. J Biomed Mater Res B Appl Biomater 2020; 109:744-764. [PMID: 33075186 DOI: 10.1002/jbm.b.34740] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/17/2020] [Accepted: 09/30/2020] [Indexed: 01/17/2023]
Abstract
Preceramic organosilicon materials combining the properties of a polymer and an inorganic ceramic phase are of great interest to scientists working in biomedical sciences. The interdisciplinary nature of organosilicon polymers and their molecular structures, as well as their diversity of applications have resulted in an unprecedented range of devices and synergies cutting across unrelated fields in medicine and engineering. Organosilicon materials, especially the polysiloxanes, have a long history of industrial and medical uses in many versatile aspects as they can be easily fabricated into complex-shaped products using a wide variety of computer-aided or polymer manufacturing techniques. Thus far, intensive research activities have been mainly devoted to the processing of preceramic organosilicon polymers toward magnetic, electronic, structural, optical, and not biological applications. Herein we present innovative research studies and recent developments of preceramic organosilicon polymers at the interface with biological systems, displaying the versatility and multi-functionality of these materials. This article reviews recent research on preceramic organosilicon polymers and corresponding composites for bone tissue regeneration and medical engineering implants, focusing on three particular topics: (a) surface modifications to create tailorable and bioactive surfaces with high corrosion resistance and improved biological properties; (b) biological evaluations for specific applications, such as in glaucoma drainage devices, orthopedic implants, bone tissue regeneration, wound dressing, drug delivery systems, and antibacterial activity; and (c) in vitro and in vivo studies for cytotoxicity, genotoxicity, and cell viability. The interest in organosilicon materials stems from the fact that a vast array of these materials have complementary attributes that, when integrated appropriately with functional fillers and carefully controlled conditions, could be exploited either as polymeric Si-based composites or as organosilicon polymer-derived Si-based ceramic composites to tailor and optimize properties of the Si-based materials for various proposed applications.
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Affiliation(s)
- Adel Francis
- Department of Advanced Materials, Central Metallurgical R & D Institute (CMRDI), Helwan, Cairo, Egypt
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30
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Martin J, Wehbi M, Echalier C, Hunger S, Bethry A, Garric X, Pinese C, Martinez J, Vezenkov L, Subra G, Mehdi A. Direct Synthesis of Peptide-Containing Silicones: A New Way to Bioactive Materials. Chemistry 2020; 26:12839-12845. [PMID: 32516440 DOI: 10.1002/chem.202001571] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 05/26/2020] [Indexed: 11/09/2022]
Abstract
A simple and efficient way to synthesize peptide-containing silicone materials is described. Silicone oils containing a chosen ratio of bioactive peptide sequences were prepared by acid-catalyzed copolymerization of dichlorodimethylsilane, hybrid dichloromethyl peptidosilane, and Si(vinyl)- or SiH-functionalized monomers. Functionalized silicone oils were first obtained and then, after hydrosilylation cross-linking, bioactive polydimethylsiloxane (PDMS)-based materials were straightforwardly obtained. The introduction of an antibacterial peptide yielded PDMS materials showing activity against Staphylococcus aureus. PDMS containing RGD ligands showed improved cell-adhesion properties. This generic method was fully compatible with the stability of peptides and thus opened the way to the synthesis of a wide range of biologically active silicones.
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Affiliation(s)
- Julie Martin
- CNRS, ENSCM, ICGM Univ. Montpellier, 34095, Montpellier, France.,CNRS, ENSCM, IBMM Univ. Montpellier, 34095, Montpellier, France
| | - Mohammad Wehbi
- CNRS, ENSCM, ICGM Univ. Montpellier, 34095, Montpellier, France
| | - Cécile Echalier
- CNRS, ENSCM, ICGM Univ. Montpellier, 34095, Montpellier, France.,CNRS, ENSCM, IBMM Univ. Montpellier, 34095, Montpellier, France
| | - Sylvie Hunger
- CNRS, ENSCM, IBMM Univ. Montpellier, 34095, Montpellier, France
| | - Audrey Bethry
- CNRS, ENSCM, IBMM Univ. Montpellier, 34095, Montpellier, France
| | - Xavier Garric
- CNRS, ENSCM, IBMM Univ. Montpellier, 34095, Montpellier, France
| | - Coline Pinese
- CNRS, ENSCM, IBMM Univ. Montpellier, 34095, Montpellier, France
| | - Jean Martinez
- CNRS, ENSCM, IBMM Univ. Montpellier, 34095, Montpellier, France
| | | | - Gilles Subra
- CNRS, ENSCM, IBMM Univ. Montpellier, 34095, Montpellier, France
| | - Ahmad Mehdi
- CNRS, ENSCM, ICGM Univ. Montpellier, 34095, Montpellier, France
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Mojsiewicz-Pieńkowska K, Stachowska E, Krenczkowska D, Bazar D, Meijer F. Evidence of Skin Barrier Damage by Cyclic Siloxanes ( Silicones)-Using Digital Holographic Microscopy. Int J Mol Sci 2020; 21:ijms21176375. [PMID: 32887477 PMCID: PMC7504040 DOI: 10.3390/ijms21176375] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Accepted: 08/31/2020] [Indexed: 11/16/2022] Open
Abstract
Cyclic siloxanes (D4, D5, D6) are widely used in skin products. They improve skin sensory properties and alleviate dry skin, but there is still one report (published 2019), which regards their effects on the destruction of the skin barrier, by using fluorescence microscopy and attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR). A new skin-imaging technique, digital holographic microscopy (DHM), was used for the first time to investigate the impact of D4, D5, and D6 on the skin barrier. We observed irreversible damage of the stratum corneum due to the interaction with cyclic siloxanes. These substances changed: (a) the first level of the skin barrier through destabilization of the intercellular lipid lamellae and destruction of the corneocyte structure (measured with axial nanometer resolution), (b) the second level by collapse of not only corneocytes but also of a significant part of the clusters, leading to the loss of the stratum corneum integrity and formation of the lacunae, (c) the third level as an effect of the change in the surface geometrical topography of the stratum corneum and disruption of the integrity of this skin layer, measured with lateral micrometer resolution. DHM allowed also to identify an important pathway for substances to penetrate into the skin through canyons surrounding the clusters. Our investigations provide advanced information for understanding the mechanisms by which various substances pass the skin barrier, including uncontrolled diffusion into the skin.
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Affiliation(s)
- Krystyna Mojsiewicz-Pieńkowska
- Department of Physical Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, al. gen. Józefa Hallera 107, 80-416 Gdańsk, Poland; (D.K.); (D.B.)
- Correspondence: ; Tel.: +48-58-3491656
| | - Ewa Stachowska
- Department of Metrology and Measurement Systems, Faculty of Mechanical Engineering and Management, Poznan University of Technology, ul. Piotrowo 3, 60-965 Poznan, Poland; (E.S.); (F.M.)
| | - Dominika Krenczkowska
- Department of Physical Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, al. gen. Józefa Hallera 107, 80-416 Gdańsk, Poland; (D.K.); (D.B.)
| | - Dagmara Bazar
- Department of Physical Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, al. gen. Józefa Hallera 107, 80-416 Gdańsk, Poland; (D.K.); (D.B.)
| | - Frans Meijer
- Department of Metrology and Measurement Systems, Faculty of Mechanical Engineering and Management, Poznan University of Technology, ul. Piotrowo 3, 60-965 Poznan, Poland; (E.S.); (F.M.)
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Abstract
Multiple techniques for skin graft fixation have been proposed, but the evidence underlying these techniques is unclear. This study aimed to review the literature for full-thickness graft fixation techniques. PubMed was electronically searched to identify relevant studies. The search strategy identified 91 relevant articles. These consisted of 2 randomised controlled trials (RCTs), 10 observational cohort studies (8 retrospective, 2 prospective), and 79 descriptive studies (case series, case reports, or expert opinion articles). Both identified RCTs compared the tie-over dressing against a modified tie-over dressing. The tie-over dressing was also included in all identified observational studies, and comparisons were made against quilting/mattress suturing (4 studies, 181 grafts in total), simple pressure dressings (3 studies, 528 grafts), non-tie-over dressings non-specifically (1 study, 71 grafts), hydrocolloid dressings (1 study, 62 grafts), and double-tie over dressings (1 study, 43 grafts). No significant differences were found between fixation methods for graft take, haematoma rate, and infection rate. No studies have found a significant difference between tie-over dressings and alternative graft fixation technique, with the most evidence for simple pressure dressings and quilting/mattress suturing. However, the evidence base consists mostly of small, retrospective observational studies. This article describes the current evidence base and this should be considered when planning future reports in the field.
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Affiliation(s)
- Lloyd Steele
- Department of Dermatology, The Royal London Hospital, Barts Health NHS Trust, London, UK
| | - Alistair Brown
- Department of Dermatology, University Hospitals Plymouth NHS Trust, UK
| | - Fangyi Xie
- Department of Dermatology, Royal Devon and Exeter NHS Foundation Trust, UK
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Krenczkowska D, Mojsiewicz-Pieńkowska K, Wielgomas B, Bazar D, Jankowski Z. Ex Vivo Human Skin is not a Barrier for Cyclic Siloxanes (Cyclic Silicones): Evidence of Diffusion, Bioaccumulation, and Risk of Dermal Absorption Using a New Validated GC-FID Procedure. Pharmaceutics 2020; 12:pharmaceutics12060586. [PMID: 32599732 PMCID: PMC7355424 DOI: 10.3390/pharmaceutics12060586] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 06/14/2020] [Accepted: 06/23/2020] [Indexed: 12/20/2022] Open
Abstract
Cyclic methylsiloxanes D4, D5, D6 (also called cyclic silicones) are widely used in various dermatological products and cosmetics, both for children and adults. As a result of their unique physicochemical properties, the production of cyclic methylsiloxanes has greatly increased over the last few years, which has resulted in increased exposure to mankind. The validated quantitative for gas chromatography-flame ionization detector (GC-FID) analysis with using the transdermal diffusion system with vertical Franz cells demonstrated that ex vivo human skin is not a barrier to cyclic siloxanes. D4, D5, and D6 have a specific affinity to stratum corneum (SC) (especially D6), and can even diffuse into the deeper layers of the skin (epidermis (E) and dermis (D)), or into the receptor fluid as well. An important achievement of this work was the observation of the characteristic ratio partitioning D4, D5, and D6 in skin layers and receptor fluid (RF). The studies have shown that, in order to thoroughly understand the mechanism, it is important to determine not only the differences in the amounts of cumulated doses in total in all skin layers and receptor fluid, but also the mutual ratios of analyte concentrations existing between matrices. For example, in the case of the stratum corneum, the cumulative doses of D4, D5, and D6 were 27.5, 63.9, and 67.2 µg/cm2/24 h, respectively, and in the epidermis, they were 6.9, 29.9, and 10.7 µg/cm2/24 h, respectively, which confirmed the highest affinity of D6 to stratum corneum as the amount diffused into the epidermis was 2.8 times smaller compared to D5. The calculated epidermis-to-stratum corneum ratios of analyte concentrations also confirm this. The largest ratio was identified for D5 (E/SC = 47), followed by D4 (E/SC = 25), and finally by D6 (E/SC = 16). The analysis of the next stage of diffusion from epidermis to dermis revealed that in dermis the highest cumulative dose was observed for D5 (13.9 µg/cm2/24 h), while the doses of D4 and D6 were similar (5.1 and 5.3 µg/cm2/24 h). Considering the concentration gradient, it can be concluded that the diffusion of D5 and D6 occurs at a similar level, while D4 diffuses at a much higher level. These observations were also confirmed by the dermis-to-epidermis concentration ratios. The final stage of diffusion from dermis to the receptor fluid indicated that D4 was able to permeate easily, while D5 exhibited a difficult diffusion and the diffusion of D6 was limited. The receptor fluid-to-dermis concentration ratios (RF/D) were calculated for D4, D5, and D6: 80, 53, and 17, respectively. Our results also revealed the increased risk of D4 and D5 absorption into the blood and lymphatic systems, whereas D6 demonstrated the lowest risk. Therefore, we can argue that, among the three tested compounds, D6 is the safest one that can be used in dermatological, cosmetic, and personal care products. This study demonstrates that the stratum corneum, epidermis, and dermis can be also considered reservoirs of cyclic methylsiloxanes. Therefore, these compounds can demonstrate potential long-term bioaccumulation, and can be absorbed to the bloodstream in a long-term and uncontrolled process.
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Affiliation(s)
- Dominika Krenczkowska
- Department of Physical Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, Al. J. Gen. Hallera 107, 80-416 Gdańsk, Poland; (D.K.); (D.B.)
| | - Krystyna Mojsiewicz-Pieńkowska
- Department of Physical Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, Al. J. Gen. Hallera 107, 80-416 Gdańsk, Poland; (D.K.); (D.B.)
- Correspondence: ; Tel.: +48-58-3491656
| | - Bartosz Wielgomas
- Department of Toxicology, Faculty of Pharmacy, Medical University of Gdańsk, Al. J. Gen. Hallera 107, 80-416 Gdańsk, Poland;
| | - Dagmara Bazar
- Department of Physical Chemistry, Faculty of Pharmacy, Medical University of Gdańsk, Al. J. Gen. Hallera 107, 80-416 Gdańsk, Poland; (D.K.); (D.B.)
| | - Zbigniew Jankowski
- Department of Forensic Medicine, Faculty of Medicine, Medical University of Gdańsk, ul. Dębowa 23, 80-204 Gdańsk, Poland;
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Wiseman O, Ventimiglia E, Doizi S, Kleinclauss F, Letendre J, Cloutier J, Traxer O. Effects of Silicone Hydrocoated Double Loop Ureteral Stent on Symptoms and Quality of Life in Patients Undergoing Flexible Ureteroscopy for Kidney Stone: A Randomized Multicenter Clinical Study. J Urol 2020; 204:769-77. [PMID: 32364838 DOI: 10.1097/JU.0000000000001098] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE We compared the hydrocoated silicone stent (Coloplast Imajin® hydro) to Percuflex™ Plus stent (Boston Scientific) in terms of patient comfort and quality of life after flexible ureteroscopy for stone disease over a 5-week prospective followup. MATERIALS AND METHODS This is a multicenter, single-blind, prospective, randomized trial of 141 patients treated with flexible ureteroscopy for renal stones. Primary outcome was Ureteral Stent Symptom Questionnaire (USSQ) Body Pain Index recorded before Double-J® stent removal at day (D) 20. Secondary endpoints were USSQ scores at intermediate dates (D2, D7, D20) and 2 weeks after stent withdrawal (D35), occurrence of adverse events and stent encrustation. RESULTS The trial was completed by 113 (80.1%) patients. Mean (SD) USSQ body pain scores were 25% lower at D20 for the silicone stent at 18.7 (11.4) vs 25.1 (14.2) (p=0.015). No difference in terms of adverse events and safety profile was observed. USSQ urinary symptoms scores at D2, D7 and D20 were lower in the silicone stent group at 26.4 (7.7) vs 31.8 (8.1) at D20 (p <0.001). The use of USSQ self-questionnaires was associated with a limited number of missing or incomplete answers. CONCLUSIONS The primary results of this large sample prospective randomized controlled study comparing the silicone Imajin hydro stents to the Percuflex Plus stent show that silicone stents are associated with significantly less patient discomfort. We would recommend their use in patients who require stenting for stone disease.
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35
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Mehta RM, Godara R, Bhat RS, Loknath C, Singla A. A Novel Technique for the Management of Massive Hemoptysis: The Customized Endobronchial Silicone Blocker. Innovations (Phila) 2020; 15:142-147. [PMID: 32352902 DOI: 10.1177/1556984520904351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Massive hemoptysis (MH) has a high mortality rate. Therapeutic options include bronchoscopy for endobronchial lesions, bronchial artery embolization (BAE), and emergency surgery. Scant options exist for patients who are not candidates for these modalities. Culprit bronchial segment occlusion is an option to prevent "spillover flooding → hypoxia." Applying this concept, we describe a case series of MH control using a novel bronchoscopically inserted customized endobronchial silicone blocker (CESB). We analyzed the safety and efficacy of CESBs in a select subset of patients with MH. METHODS Inclusion criteria were patients with MH who were unstable for surgery/BAE, failed BAE, or relatively contraindicated/refused BAE. CESBs were manufactured on-site by modifying silicone stents, inserted using rigid bronchoscopy and reinforced with glue. The CESB was removed after 6 weeks when possible. A successful outcome was defined as immediate bleeding control with no recurrence after removal. RESULTS Over 4.5 years, 13 episodes of MH in 12 patients meeting the criteria specified earlier were treated with CESBs. Seven of 12 patients had tuberculosis, 4 active and 3 inactive. One patient had mucormycosis, 1 post-lobectomy, 1 endobronchial renal cell carcinoma, 1 fibrosing mediastinitis, and 1 patient had metastatic laryngeal Ca. Eight of 12 patients were taken for primary-CESB placement. Four of 12 patients were sent for BAE, which was unsuccessful, and rescue-CESB was done for definitive management. The success rate, as defined earlier, was 92.3%, with no deaths from MH. CONCLUSIONS Innovative bronchoscopically inserted CESBs are an effective strategy in MH when patients are unstable or fail conventional management.
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Affiliation(s)
- Ravindra M Mehta
- 75438 Department of Interventional Pulmonolgy, Apollo Hospitals, Bengaluru, Karnataka, India
| | - Rakesh Godara
- 75438 Department of Interventional Pulmonolgy, Apollo Hospitals, Bengaluru, Karnataka, India
| | - Rajani Surendar Bhat
- 75438 Department of Interventional Pulmonolgy, Apollo Hospitals, Bengaluru, Karnataka, India
| | - Chakravarthi Loknath
- 75438 Department of Interventional Pulmonolgy, Apollo Hospitals, Bengaluru, Karnataka, India
| | - Abhinav Singla
- 75438 Department of Interventional Pulmonolgy, Apollo Hospitals, Bengaluru, Karnataka, India
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Faiczak K, Brook MA, Feinle A. Energy-Dissipating Polymeric Silicone Surfactants. Macromol Rapid Commun 2020; 41:e2000161. [PMID: 32346942 DOI: 10.1002/marc.202000161] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/14/2020] [Accepted: 04/15/2020] [Indexed: 11/06/2022]
Abstract
Materials that are able to withstand impact loadings by dissipating energy are crucial for a broad range of different applications, including personal protective applications. Shear-thickening fluids (STFs) are often used for this purpose, but their preparation is still limited, in part, to high production costs. It is demonstrated that polymeric surfactants comprised of linear telechelic sugar-modified silicones-with neither additives nor particles-generate transient polymer networks (TPNs) that represent a promising alternative to STFs. The reported polymers have distinct viscoelastic properties and can turn from a liquid into a rubbery network when force is applied. Saccharide-modified silicones with short chains (degree of polymerization (DP) ≈ 34, 68) are solids, but become energy-absorbing viscoelastic fluids when diluted in low-viscosity silicone oils; longer silicones (DP ≈ 338, 675) with low saccharide contents are viscoelastic fluids at room temperature. Excellent damping properties are found for the reported silicone surfactants, even those containing only 0.1% saccharides. The degree of energy absorption can be tailored simply by controlling the sugar/silicone ratio.
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Affiliation(s)
- Kyle Faiczak
- McMaster University, Department of Chemistry and Chemical Biology, 1280 Main Street West, Hamilton, ON, L8S 4M1, Canada
| | - Michael A Brook
- McMaster University, Department of Chemistry and Chemical Biology, 1280 Main Street West, Hamilton, ON, L8S 4M1, Canada
| | - Andrea Feinle
- McMaster University, Department of Chemistry and Chemical Biology, 1280 Main Street West, Hamilton, ON, L8S 4M1, Canada.,Paris-Lodron University Salzburg, Department of Chemistry and Physics of Materials, Jakob-Haringer Str. 2A, Salzburg, Austria, 5020
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Kis N, Kovács A, Budai-Szűcs M, Gácsi A, Csányi E, Csóka I, Berkó S. Investigation of Silicone-Containing Semisolid in Situ Film-Forming Systems Using QbD Tools. Pharmaceutics 2019; 11:E660. [PMID: 31817871 PMCID: PMC6956232 DOI: 10.3390/pharmaceutics11120660] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 12/04/2019] [Accepted: 12/05/2019] [Indexed: 12/13/2022] Open
Abstract
The aim of our research work was to develop dermally applicable, semisolid film-forming systems (FFSs) containing silicones, which form a film on the skin in situ, with suitable mechanical properties for skin application. FFSs were developed and investigated by means of the Quality by Design (QbD) methodology. With this QbD approach, the initial risk assessment defines the critical quality attributes (CQAs), the critical material attributes (CMAs) and the critical process parameters (CPPs) to ensure the required quality. Different semisolid systems were formed with or without silicones. During the initial risk assessment, three CQAs, namely skin adhesion, film flexibility and burst strength, were found to be critical attributes, while film appearance, film integrity and the drying time of the semisolid system, were found to be medium attributes. These parameters were investigated. The initial risk assessment also showed that there are three high CMAs: the type of silicones, film-forming excipients, drying excipients, and that there was one medium CMA: viscosity-enhancing excipients. Based on our results, the silicone content had a great effect on the film-forming systems. Different silicones affected the mechanical properties of the films in varying ways, decreased the drying time and showed promising results regarding the drying mechanism.
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Affiliation(s)
| | | | | | | | | | | | - Szilvia Berkó
- Institute of Pharmaceutical Technology and Regulatory Affairs, Faculty of Pharmacy, University of Szeged, 6720 Szeged, Hungary; (N.K.); (A.K.); (M.B.-S.); (A.G.); (E.C.); (I.C.)
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Azumaguchi A, Henmi H, Saito T. Efficacy of silicone sheet as a personalized barrier for preventing adhesion reformation after hysteroscopic adhesiolysis of intrauterine adhesions. Reprod Med Biol 2019; 18:378-383. [PMID: 31607798 PMCID: PMC6780041 DOI: 10.1002/rmb2.12294] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 07/28/2019] [Accepted: 07/29/2019] [Indexed: 12/25/2022] Open
Abstract
PURPOSE To evaluate the efficacy of silicone sheet as a new type of barrier for preventing adhesion reformation following hysteroscopic adhesiolysis of intrauterine adhesions (IUAs). METHODS Hysteroscopic adhesiolysis was performed for 36 patients with IUAs. The adhesion reformation rate was retrospectively compared between 26 patients treated with silicone sheet (group 1) and 10 patients treated with an intrauterine device wrapped in oxidized regenerated cellulose as a barrier (group 2). For patients in group 1, a 1-mm-thick silicone sheet was cut to fit the size and shape of the individual uterine cavity as a personalized barrier. RESULTS The size and shape of each silicone sheet used for patients in group 1 differed significantly. The adhesion reformation rate was significantly lower in group 1 (4/26, 15.4%) than in group 2 (4/10, 40.0%; P = 0.03), although the pregnancy rate (14/20, 70.0% vs. 5/10, 50.0%; P = 0.28) and miscarriage rate (2/14, 14.3% vs. 1/5, 20.0%; P = 0.72) were not significantly different. CONCLUSION Use of silicone sheets appears to be effective for preventing adhesion reformation following hysteroscopic adhesiolysis of IUAs. This is the first study to investigate the efficacy of silicone sheet used as a personalized barrier for preventing IUAs.
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Affiliation(s)
| | - Hirofumi Henmi
- Department of Gynecology and Reproductive Endocrinology, National Public Service Mutual Aid AssociationTonan HospitalSapporoJapan
| | - Tsuyoshi Saito
- Department of Obstetrics and GynecologySapporo Medical UniversitySapporoJapan
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Wohlgemuth FB, Brasil MBQ, d'Acampora AJ. Risk of breast implant-associated anaplastic large cell lymphoma in patients submitted to breast implantation: A systematic review. Breast J 2019; 25:932-937. [PMID: 31155830 DOI: 10.1111/tbj.13370] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2018] [Revised: 11/27/2018] [Accepted: 11/28/2018] [Indexed: 11/28/2022]
Abstract
Although breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare disease, its incidence has been increasing. The aim of this study was to assess the risk of BIA-ALCL in women with breast implants. A systematic search was carried out in Pubmed, Scopus, ScienceDirect, LIVIVO, Cochrane Library, Google Scholar, and OpenGrey databases. The risk assessment of bias was based on the Newcastle-Ottawa Scale. The rarity of BIA-ALCL was a major limitation. Although we have found evidence of an increased risk of BIA-ALCL, further studies are needed to understand why some large samples did not present any case of the disease.
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Affiliation(s)
- Felipe Barbieri Wohlgemuth
- Programa de Pós-Graduação em Ciências Médicas, Hospital Universitário - Universidade Federal de Santa Catarina, Florianópolis, Brasil
| | - Marília Bastos Quirino Brasil
- Programa de Pós-Graduação em Ciências Médicas, Hospital Universitário - Universidade Federal de Santa Catarina, Florianópolis, Brasil
| | - Armando José d'Acampora
- Programa de Pós-Graduação em Ciências Médicas, Hospital Universitário - Universidade Federal de Santa Catarina, Florianópolis, Brasil
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Devasahayam S, Raman RKS, Chennakesavulu K, Bhattacharya S. Plastics-Villain or Hero? Polymers and Recycled Polymers in Mineral and Metallurgical Processing-A Review. Materials (Basel) 2019; 12:E655. [PMID: 30795608 PMCID: PMC6416741 DOI: 10.3390/ma12040655] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 02/03/2019] [Accepted: 02/05/2019] [Indexed: 11/16/2022]
Abstract
This review focusses on the use of recycled and virgin polymers in mineral and metallurgical processing, both high and ambient temperature processes, including novel applications. End of life applications of polymers as well as the utilisation of polymers during its life time in various applications are explored. The discussion includes applications in cleaner coal production, iron and steel production, iron ore palletisation, iron alloy manufacturing, manganese processing, E-wastes processing and carbon sequestration. The underlying principles of these applications are also explained. Advantages and disadvantages of using these polymers in terms of energy and emission reductions, reduction in non-renewables and dematerialisation are discussed. Influence of the polymers on controlling the evolution of micro and nanostructures in alloys and advanced materials is also considered.
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Affiliation(s)
- Sheila Devasahayam
- Department of Chemical Engineering, Monash University, Clayton Campus, Victoria 3800, Australia.
| | - R K Singh Raman
- Department of Chemical Engineering, Monash University, Clayton Campus, Victoria 3800, Australia.
- Department of Mechanical & Aerospace Engineering, Monash University, Clayton Campus, Victoria 3800, Australia.
| | - K Chennakesavulu
- Laboratory of Supramolecular Chemistry, Institut de Science et d'Ing'enierie Supramol'eculaires (ISIS), UMR 7006, CNRS, Universit'e de Strasbourg, 8 allee Gaspard Monge, 67000 Strasbourg, France.
- Department of Chemistry & International Research Centre, Sathyabama Institute of Science and Technology (Deemed to be University), Chennai 600 119, India.
| | - Sankar Bhattacharya
- Department of Chemical Engineering, Monash University, Clayton Campus, Victoria 3800, Australia.
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Kizilkan E, Gorb SN. Bioinspired Further Enhanced Dry Adhesive by the Combined Effect of the Microstructure and Surface Free-Energy Increase. ACS Appl Mater Interfaces 2018; 10:26752-26758. [PMID: 30010312 DOI: 10.1021/acsami.8b06686] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Silicone elastomers are known for having low surface free energies generally leading to poor adhesive performances. This surface characteristic can be enhanced by plasma treatments. The microstructured silicone elastomer surfaces can demonstrate superior adhesive performance that is more than 10 times higher in terms of pull-off forces, compared to their unstructured counterpart. Here, we have demonstrated that the combination of these two methods further enhances adhesive performance, especially when the surfaces are biomimetic micro/nanopatterned with, e.g., beetle-inspired mushroom-shaped adhesive microstructure (MSAMS). The plasma treatment time and pressure parameters were varied for the unstructured and MSAMS poly(vinylsiloxane) surfaces to find optimum parameters for maximum adhesion performance. Air plasma treatment induced average adhesive enhancement forces up to 30% on the unstructured surface, but the MSAMS surface demonstrated an enhancement of adhesive forces up to 91% higher than that of an untreated, microstructured control, despite the plasma-treated surface area of the structured surface being only 50% of that of the unstructured surface. High-speed video-recordings of individual microstructures in contact with a glass surface shows that the origin of the adhesion enhancement is due to the special detachment mechanism of individual microstructures that allows sustaining a wider contact area at detachment. We believe that this integration of the plasma treatment with MSAMS suggests a versatile way of functionalization that can further advance the adhesive ability of low-surface-energy polymer surfaces.
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Affiliation(s)
- Emre Kizilkan
- Department of Functional Morphology and Biomechanics , Zoological Institute, Kiel University , Am Botanischen Garten 1-9 , 24118 Kiel , Germany
| | - Stanislav N Gorb
- Department of Functional Morphology and Biomechanics , Zoological Institute, Kiel University , Am Botanischen Garten 1-9 , 24118 Kiel , Germany
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42
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Park S, Mondal K, Treadway RM, Kumar V, Ma S, Holbery JD, Dickey MD. Silicones for Stretchable and Durable Soft Devices: Beyond Sylgard-184. ACS Appl Mater Interfaces 2018; 10:11261-11268. [PMID: 29578686 DOI: 10.1021/acsami.7b18394] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This paper identifies and characterizes silicone elastomers that are well-suited for fabricating highly stretchable and tear-resistant devices that require interfacial bonding by plasma or UV ozone treatment. The ability to bond two or more pieces of molded silicone is important for creating microfluidic channels, chambers for pneumatically driven soft robotics, and other soft and stretchable devices. Sylgard-184 is a popular silicone, particularly for microfluidic applications. However, its low elongation at break (∼100% strain) and moderate tear strength (∼3 N/mm) make it unsuitable for emerging, mechanically demanding applications of silicone. In contrast, commercial silicones, such as Dragon Skin, have excellent mechanical properties yet are difficult to plasma-bond, likely because of the presence of silicone oils that soften the network yet migrate to the surface and interfere with plasma bonding. We found that extracting silicone oligomers from these soft networks allows these materials to bond but only when the Shore hardness exceeds a value of 15 A. It is also possible to mix highly stretchable silicones (Dragon Skin and Ecoflex) with Sylgard-184 to create silicones with intermediate mechanical properties; interestingly, these blends also only bond when the hardness exceeds 15 A. Eight different Pt-cured silicones were also screened; again, only those with Shore hardness above 15 A plasma-bond. The most promising silicones from this study are Sylgard-186 and Elastosil-M4130 and M4630, which exhibit a large deformation (>200% elongation at break), high tear strength (>12 N/mm), and strong plasma bonding. To illustrate the utility of these silicones, we created stretchable electrodes by injecting a liquid metal into microchannels created using such silicones, which may find use in soft robotics, electronic skin, and stretchable energy storage devices.
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Affiliation(s)
- Sungjune Park
- Department of Chemical and Biomolecular Engineering , North Carolina State University , 911 Partners Way , Raleigh , North Carolina 27695 , United States
| | - Kunal Mondal
- Department of Chemical and Biomolecular Engineering , North Carolina State University , 911 Partners Way , Raleigh , North Carolina 27695 , United States
| | - Robert M Treadway
- Department of Chemical and Biomolecular Engineering , North Carolina State University , 911 Partners Way , Raleigh , North Carolina 27695 , United States
| | - Vikash Kumar
- Department of Chemical and Biomolecular Engineering , North Carolina State University , 911 Partners Way , Raleigh , North Carolina 27695 , United States
| | - Siyuan Ma
- Applied Sciences Group , Microsoft Corporation , Redmond 98052 , Washington , United States
| | - James D Holbery
- Applied Sciences Group , Microsoft Corporation , Redmond 98052 , Washington , United States
| | - Michael D Dickey
- Department of Chemical and Biomolecular Engineering , North Carolina State University , 911 Partners Way , Raleigh , North Carolina 27695 , United States
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Pinheiro JB, Vomero MP, do Nascimento C, Watanabe E, Paranhos HDFO, Coto NP, Dias RB, Oliveira VCD, Silva-Lovato CH. Genomic identification of microbial species adhering to maxillofacial prostheses and susceptibility to different hygiene protocols. Biofouling 2018; 34:15-25. [PMID: 29258349 DOI: 10.1080/08927014.2017.1403591] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 11/03/2017] [Indexed: 06/07/2023]
Abstract
This study investigated the microbial colonization of maxillofacial prostheses and support tissues using the Checkerboard DNA-DNA hybridization method, and the efficacy of 0.12% chlorhexidine gluconate, 10% Ricinus communis solutions, or brushing, on colony forming unit (CFU) reduction in monospecies biofilms (Candida glabrata, Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa) formed on two silicones (MDX 4-4210 and Bio-Skin). Biofilm was harvested from 43 maxillofacial prosthesis wearers for detection of 38 species of microorganisms. The CFU counts of the six above mentioned species were recorded after using the hygiene protocols. All 38 investigated species were identified in prostheses and tissues, with a higher prevalence in the prostheses. 0.12% chlorhexidine gluconate immersion showed the greatest antimicrobial effectiveness, followed by mechanical brushing protocols. MDX 4-4210 silicone produced lower CFU counts than Bio-Skin.
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Affiliation(s)
- Juliana Barchelli Pinheiro
- a Department of Dental Materials and Prostheses, School of Dentistry of Ribeirao Preto , University of Sao Paulo , Sao Paulo , Brazil
| | - Marina Peris Vomero
- a Department of Dental Materials and Prostheses, School of Dentistry of Ribeirao Preto , University of Sao Paulo , Sao Paulo , Brazil
| | - Cássio do Nascimento
- a Department of Dental Materials and Prostheses, School of Dentistry of Ribeirao Preto , University of Sao Paulo , Sao Paulo , Brazil
| | - Evandro Watanabe
- b Department of Restorative Dentistry, School of Dentistry of Ribeirao Preto , University of Sao Paulo , Sao Paulo , Brazil
| | | | - Neide Pena Coto
- c Department of Maxillofacial Surgery, Prostheses and Traumatology, School of Dentistry of Sao Paulo , University of Sao Paulo , Sao Paulo , Brazil
| | - Reinaldo Brito Dias
- c Department of Maxillofacial Surgery, Prostheses and Traumatology, School of Dentistry of Sao Paulo , University of Sao Paulo , Sao Paulo , Brazil
| | - Viviane Cássia de Oliveira
- a Department of Dental Materials and Prostheses, School of Dentistry of Ribeirao Preto , University of Sao Paulo , Sao Paulo , Brazil
| | - Cláudia Helena Silva-Lovato
- a Department of Dental Materials and Prostheses, School of Dentistry of Ribeirao Preto , University of Sao Paulo , Sao Paulo , Brazil
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Wenning BM, Martinelli E, Mieszkin S, Finlay JA, Fischer D, Callow JA, Callow ME, Leonardi AK, Ober CK, Galli G. Model Amphiphilic Block Copolymers with Tailored Molecular Weight and Composition in PDMS-Based Films to Limit Soft Biofouling. ACS Appl Mater Interfaces 2017; 9:16505-16516. [PMID: 28429593 DOI: 10.1021/acsami.7b03168] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A set of controlled surface composition films was produced utilizing amphiphilic block copolymers dispersed in a cross-linked poly(dimethylsiloxane) network. These block copolymers contained oligo(ethylene glycol) (PEGMA) and fluoroalkyl (AF6) side chains in selected ratios and molecular weights to control surface chemistry including antifouling and fouling-release performance. Such properties were assessed by carrying out assays using two algae, the green macroalga Ulva linza (favors attachment to polar surfaces) and the unicellular diatom Navicula incerta (favors attachment to nonpolar surfaces). All films performed well against U. linza and exhibited high removal of attached sporelings (young plants) under an applied shear stress, with the lower molecular weight block copolymers being the best performing in the set. The composition ratios from 50:50 to 60:40 of the AF6/PEGMA side groups were shown to be more effective, with several films exhibiting spontaneous removal of the sporelings. The cells of N. incerta were also removed from several coating compositions. All films were characterized by surface techniques including captive bubble contact angle, atomic force microscopy, and near edge X-ray absorption fine structure spectroscopy to correlate surface chemistry and morphology with biological performance.
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Affiliation(s)
- Brandon M Wenning
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa , Pisa 56124, Italy
| | - Elisa Martinelli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa , Pisa 56124, Italy
| | - Sophie Mieszkin
- School of Biosciences, The University of Birmingham , Edgbaston, Birmingham B15 5TT, U.K
| | - John A Finlay
- School of Biosciences, The University of Birmingham , Edgbaston, Birmingham B15 5TT, U.K
| | - Daniel Fischer
- National Institute of Standards and Technology , Gaithersburg, Maryland 20899, United States
| | - James A Callow
- School of Biosciences, The University of Birmingham , Edgbaston, Birmingham B15 5TT, U.K
| | - Maureen E Callow
- School of Biosciences, The University of Birmingham , Edgbaston, Birmingham B15 5TT, U.K
| | | | | | - Giancarlo Galli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa , Pisa 56124, Italy
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Antonelli RQ, Calderoni DR, Garcia IF, Stelini RF, Fregonesi A, Kharmandayan P. Liquid silicone used for esthetic purposes as a potentiator for occurrence of post-radiotherapy genital lymphedema: case report. SAO PAULO MED J 2017; 135:185-189. [PMID: 28538870 PMCID: PMC9977334 DOI: 10.1590/1516-3180.2016.0275251016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Accepted: 10/25/2016] [Indexed: 11/21/2022] Open
Abstract
CONTEXT: Lymphedema consists of extracellular fluid retention caused by lymphatic obstruction. In chronic forms, fat and fibrous tissue accumulation is observed. Genital lymphedema is a rare condition in developed countries and may have primary or acquired etiology. It generally leads to urinary, sexual and social impairment. Clinical treatment usually has low effectiveness, and surgical resection is frequently indicated. CASE REPORT: We report a case of a male-to-female transgender patient who was referred for treatment of chronic genital lymphedema. She had a history of pelvic radiotherapy to treat anal cancer and of liquid silicone injections to the buttock and thigh regions for esthetic purposes. Radiological examinations showed signs both of tissue infiltration by liquid silicone and of granulomas, lymphadenopathy and lymphedema. Surgical treatment was performed on the area affected, in which lymphedematous tissue was excised from the scrotum while preserving the penis and testicles, with satisfactory results. Histopathological examination showed alterations compatible with tissue infiltration by exogenous material, along with chronic lymphedema. CONCLUSION: Genital lymphedema may be caused by an association of lesions due to liquid silicone injections and radiotherapy in the pelvic region. Cancer treatment decisions for patients who previously underwent liquid silicone injection should take this information into account, since it may represent a risk factor for radiotherapy complications.
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Affiliation(s)
- Raíssa Quaiatti Antonelli
- MD. Resident Physician, Department of Surgery, Faculdade de Ciências Médicas da Universidade Estadual de Campinas (FCM/UNICAMP), Campinas (SP), Brazil.
| | - Davi Reis Calderoni
- MD, PhD. Attending Physician. Division of Plastic Surgery, Department of Surgery, Faculty of Medical Sciences, Universidade Estadual de Campinas (UNICAMP), Campinas (SP), Brazil.
| | - Igor Ferreira Garcia
- MD. Resident Physician, Department of Surgery, Faculdade de Ciências Médicas da Universidade Estadual de Campinas (FCM/UNICAMP), Campinas (SP), Brazil.
| | - Rafael Fantelli Stelini
- MD. Attending Physician, Department of Pathology, Faculdade de Ciências Médicas da Universidade Estadual de Campinas (FCM/UNICAMP), Campinas (SP), Brazil.
| | - Adriano Fregonesi
- MD, PhD. Attending Physician, Division of Urology, Department of Surgery, Faculdade de Ciências Médicas da Universidade Estadual de Campinas (FCM/UNICAMP), Campinas (SP), Brazil.
| | - Paulo Kharmandayan
- MD, PhD. Associate Professor, Head of the Division of Plastic Surgery, Department of Surgery, Faculdade de Ciências Médicas da Universidade Estadual de Campinas (FCM/UNICAMP), Campinas (SP), Brazil.
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Mahomed A, Pormehr NB. Effect of accelerated aging on the cross-link density of medical grade silicones. Biomed Mater Eng 2016; 27:437-449. [PMID: 27885992 DOI: 10.3233/bme-161598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Four specimens of Nagor silicone of different hardness (soft, medium and hard) were swollen, until they reached equilibrium (i.e. constant mass) in five liquids at 25°C, before and after accelerated aging. For the specimens swollen before accelerated aging, the greatest swelling was obtained in methyl cyclohexane, while for the specimens swollen after accelerated aging, the greatest swelling was obtained in cyclohexane. The cross-link density, υ, was also calculated from the swelling measurements for all the specimens, before and after accelerated aging, using the Flory-Rehner equation. The softer silicones, which swelled the most, had lower υ values than harder silicones. The amount of swelling (measured in terms of ϕ) and υ varied significantly (p<0.05) in some cases, between the different silicone hardness and between different liquids. Furthermore, the cross-link density, υ, significantly (p<0.05) increased after accelerated aging in most liquids.Note: ϕ is defined as the volume fraction of polymer in its equilibrium swollen state. A probability value of statistical significance of 0.05 or 5% was selected, hence if a p value of less than 0.05 was obtained, the null hypothesis was rejected (i.e. significant if p<0.05).
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Affiliation(s)
- Aziza Mahomed
- School of Engineering, Department of Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Negin Bagheri Pormehr
- School of Engineering, Department of Mechanical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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Özgül MA, Çetinkaya E, Çörtük M, Tanrıverdi E, Yıldırım BZ, Balci MK, Issaka A, Özgül G. Oki stent application in different indications: Six cases. Clin Respir J 2016; 12:234-240. [PMID: 27329014 DOI: 10.1111/crj.12521] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Revised: 05/25/2016] [Accepted: 06/18/2016] [Indexed: 11/28/2022]
Abstract
INTRODUCTION We have used Oki stents for a number of different indications. After discovering that there are limited reports in the literature on these stents, we were motivated to share our experiences in Oki stenting. OBJECTIVES While there is vast knowledge on double Y-stents, the Oki stent is a relatively recent development in pulmonology. Here, we demonstrate that stenting of the right secondary carina using an Oki stent should be considered for obstructions in this region. METHODS We placed 13 mm × 10 mm × 9 mm Oki stents in six patients under general anesthesia via rigid bronchoscopy. RESULTS Three cases were post-transplant patients with malacia, stenosis, and bronchopleural fistula. One case had an airway obstruction due to malignant disease, another case had a right aortic arc and aberrant left subclavian artery anomaly, and the final case had bronchopleural fistula. No serious complications were observed during stent placement. CONCLUSIONS Oki stents can safely be used for many clinical conditions. Patients benefit greatly from stenting; however, two of our cases died due to infection, and one case died due to malignancy.
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Affiliation(s)
- Mehmet Akif Özgül
- Department of Chest Diseases, Yedikule Chest Diseases and Thoracic Surgery Training and Research Hospital, İstanbul, Turkey
| | - Erdoğan Çetinkaya
- Department of Chest Diseases, Yedikule Chest Diseases and Thoracic Surgery Training and Research Hospital, İstanbul, Turkey
| | - Mustafa Çörtük
- Department of Chest Diseases, Karabuk University Faculty of Medicine, Karabuk, Turkey
| | - Elif Tanrıverdi
- Department of Chest Diseases, Yedikule Chest Diseases and Thoracic Surgery Training and Research Hospital, İstanbul, Turkey
| | - Binnaz Zeynep Yıldırım
- Department of Chest Diseases, Yedikule Chest Diseases and Thoracic Surgery Training and Research Hospital, İstanbul, Turkey
| | - Merih Kalamanoğlu Balci
- Kartal Kosuyolu Yuksek Ihtisas Training Hospital, Lung Transplantation Clinic, Istanbul, Turkey
| | - Adamu Issaka
- Department of Thoracic Surgery, Marmara University Faculty of Medicine, Istanbul, Turkey
| | - Güler Özgül
- Department of Chest Diseases, Bagcilar Education and Research Hospital, İstanbul, Turkey
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Wertz JT, Kuczynski JP, Boday DJ. Thermally Conductive-Silicone Composites with Thermally Reversible Cross-links. ACS Appl Mater Interfaces 2016; 8:13669-13672. [PMID: 27224959 DOI: 10.1021/acsami.6b03065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Thermally conductive-silicone composites that contain thermally reversible cross-links were prepared by blending diene- and dienophile-functionalized polydimethylsiloxane (PDMS) with an aluminum oxide conductive filler. This class of thermally conductive-silicones are useful as thermal interface materials (TIMs) within Information Technology (IT) hardware applications to allow rework of valuable components. The composites were rendered reworkable via retro Diels-Alder cross-links when temperatures were elevated above 130 °C and required little mechanical force to remove, making them advantageous over other TIM materials. Results show high thermal conductivity (0.4 W/m·K) at low filler loadings (45 wt %) compared to other TIM solutions (>45 wt %). Additionally, the adhesion of the material was found to be ∼7 times greater at lower temperatures (25 °C) and ∼2 times greater at higher temperatures (120 °C) than commercially available TIMs.
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Affiliation(s)
- J T Wertz
- IBM Corporation , Poughkeepsie, New York 12601, United States
| | - J P Kuczynski
- IBM Corporation , Tampa, Florida 33607, United States
| | - D J Boday
- IBM Corporation , Tucson, Arizona 85744, United States
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Abstract
Removal of an eye may be indicated in cases of congenital abnormality, severe trauma, or disease such as an infection, tumor, or malignancy. The disfigurement associated with a loss of an eye is often accompanied with physical problems, psychological trauma, and a poor quality of life. A prosthetic replacement is the treatment of choice to return the individual to his normal vocation by producing an acceptable and life-like appearance. This article describes prosthetic rehabilitation of a 19-year-old male suffering from facial hemiatrophy with the loss of his left eye due to retinoblastoma when he was 2-year-old using medically graded silicone material. The technique used is simple, cost effective, and easy way for fabrication and rehabilitation of an orbital defect using silicone prosthesis where retention is achieved by a combination of silicone adhesives and tapes, and to a very small extent by bony and soft tissue undercut, hence providing better esthetic and psychological outcome. The acrylic part of the prosthesis was adhered to the socket with the help of a two-way silicon adhesive tape. Since the patient had lost his eye when he was 2-year-old, the development of eye and periorbital tissue on the defect side lead to hemiatrophy; in our approach, we have attempted to build the prosthesis in par with the normal side so that the fullness on the defect side was restored to that of the contralateral side. The fabricated facial prosthesis was durable, esthetic, and had good retention.
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Affiliation(s)
- Sanath Shetty
- Department of Prosthodontics, Yenepoya Dental College, Deralakatte, Mangalore, Karnataka, India
| | - Fahad Mohammad
- Department of Prosthodontics, Yenepoya Dental College, Deralakatte, Mangalore, Karnataka, India
| | - Rajesh Shetty
- Department of Prosthodontics, Yenepoya Dental College, Deralakatte, Mangalore, Karnataka, India
| | - Kamalakanth Shenoy
- Department of Prosthodontics, Yenepoya Dental College, Deralakatte, Mangalore, Karnataka, India
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50
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Özçam AE, Efimenko K, Spontak RJ, Fischer DA, Genzer J. Multipurpose Polymeric Coating for Functionalizing Inert Polymer Surfaces. ACS Appl Mater Interfaces 2016; 8:5694-5705. [PMID: 26814561 DOI: 10.1021/acsami.5b12216] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
In this work, we report on the development of a highly functionalizable polymer coating prepared by the chemical coupling of trichlorosilane (TCS) to the vinyl groups of poly(vinylmethyl siloxane) (PVMS). The resultant PVMS-TCS copolymer can be coated as a functional organic primer layer on a variety of polymeric substrates, ranging from hydrophilic to hydrophobic. Several case studies demonstrating the remarkable and versatile properties of PVMS-TCS coatings are presented. In particular, PVMS-TCS is found to serve as a convenient precursor for the deposition of organosilanes and the subsequent growth of polymer brushes, even on hydrophobic surfaces, such as poly(ethylene terephthalate) and polypropylene. In this study, the physical and chemical characteristics of these versatile PVMS-TCS coatings are interrogated by an arsenal of experimental probes, including scanning electron microscopy, water contact-angle measurements, ellipsometry, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and near-edge X-ray absorption fine structure spectroscopy.
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Affiliation(s)
| | | | | | - Daniel A Fischer
- Materials Measurement Science Division, National Institute of Standards and Technology , Gaithersburg, Maryland 20899, United States
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