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Katsiotis CS, Tikhomirov E, Leliopoulos C, Strømme M, Welch K. Development of a simple paste for 3D printing of drug formulations containing a mesoporous material loaded with a poorly water-soluble drug. Eur J Pharm Biopharm 2024; 198:114270. [PMID: 38537908 DOI: 10.1016/j.ejpb.2024.114270] [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: 01/10/2024] [Revised: 03/11/2024] [Accepted: 03/23/2024] [Indexed: 04/19/2024]
Abstract
Poorly soluble drugs represent a substantial portion of emerging drug candidates, posing significant challenges for pharmaceutical formulators. One promising method to enhance the drug's dissolution rate and, consequently, bioavailability involves transforming them into an amorphous state within mesoporous materials. These materials can then be seamlessly integrated into personalized drug formulations using Additive Manufacturing (AM) techniques, most commonly via Fused Deposition Modeling. Another innovative approach within the realm of AM for mesoporous material-based formulations is semi-solid extrusion (SSE). This study showcases the feasibility of a straightforward yet groundbreaking hybrid 3D printing system employing SSE to incorporate drug-loaded mesoporous magnesium carbonate (MMC) into two different drug formulations, each designed for distinct administration routes. MMC was loaded with the poorly water-soluble drug ibuprofen via a solvent evaporation method and mixed with PEG 400 as a binder and lubricant, facilitating subsequent SSE. The formulation is non-aqueous, unlike most pastes which are used for SSE, and thus is beneficial for the incorporation of poorly water-soluble drugs. The 3D printing process yielded tablets for oral administration and suppositories for rectal administration, which were then analyzed for their dissolution behavior in biorelevant media. These investigations revealed enhancements in the dissolution kinetics of the amorphous drug-loaded MMC formulations. Furthermore, an impressive drug loading of 15.3 % w/w of the total formulation was achieved, marking the highest reported loading for SSE formulations incorporating mesoporous materials to stabilize drugs in their amorphous state by a wide margin. This simple formulation containing PEG 400 also showed advantages over other aqueous formulations for SSE in that the formulations did not exhibit weight loss or changes in size or form during the curing process post-printing. These results underscore the substantial potential of this innovative hybrid 3D printing system for the development of drug dosage forms, particularly for improving the release profile of poorly water-soluble drugs.
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Affiliation(s)
- Christos S Katsiotis
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Uppsala University, Box 35, Uppsala SE-751 03, Sweden.
| | - Evgenii Tikhomirov
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Uppsala University, Box 35, Uppsala SE-751 03, Sweden.
| | - Christos Leliopoulos
- Division of Macromolecular Chemistry, Department of Chemistry, Uppsala University, Box 538, SE-751 21, Sweden.
| | - Maria Strømme
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Uppsala University, Box 35, Uppsala SE-751 03, Sweden.
| | - Ken Welch
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Uppsala University, Box 35, Uppsala SE-751 03, Sweden.
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Ralph-Nearman C, Sandoval-Araujo LE, Karem A, Cusack CE, Glatt S, Hooper MA, Rodriguez Pena C, Cohen D, Allen S, Cash ED, Welch K, Levinson CA. Using machine learning with passive wearable sensors to pilot the detection of eating disorder behaviors in everyday life. Psychol Med 2024; 54:1084-1090. [PMID: 37859600 PMCID: PMC10939805 DOI: 10.1017/s003329172300288x] [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] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2023]
Abstract
BACKGROUND Eating disorders (ED) are serious psychiatric disorders, taking a life every 52 minutes, with high relapse. There are currently no support or effective intervention therapeutics for individuals with an ED in their everyday life. The aim of this study is to build idiographic machine learning (ML) models to evaluate the performance of physiological recordings to detect individual ED behaviors in naturalistic settings. METHODS From an ongoing study (Final N = 120), we piloted the ability for ML to detect an individual's ED behavioral episodes (e.g. purging) from physiological data in six individuals diagnosed with an ED, all of whom endorsed purging. Participants wore an ambulatory monitor for 30 days and tapped a button to denote ED behavioral episodes. We built idiographic (N = 1) logistic regression classifiers (LRC) ML trained models to identify onset of episodes (~600 windows) v. baseline (~571 windows) physiology (Heart Rate, Electrodermal Activity, and Temperature). RESULTS Using physiological data, ML LRC accurately classified on average 91% of cases, with 92% specificity and 90% sensitivity. CONCLUSIONS This evidence suggests the ability to build idiographic ML models that detect ED behaviors from physiological indices within everyday life with a high level of accuracy. The novel use of ML with wearable sensors to detect physiological patterns of ED behavior pre-onset can lead to just-in-time clinical interventions to disrupt problematic behaviors and promote ED recovery.
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Affiliation(s)
- C. Ralph-Nearman
- Department of Psychological & Brain Sciences, University of Louisville, Louisville, KY, USA
| | - L. E. Sandoval-Araujo
- Department of Psychological & Brain Sciences, University of Louisville, Louisville, KY, USA
| | - A. Karem
- Department of Computer Science and Engineering, University of Louisville, Louisville, KY, USA
| | - C. E. Cusack
- Department of Psychological & Brain Sciences, University of Louisville, Louisville, KY, USA
| | - S. Glatt
- Department of Psychological & Brain Sciences, University of Louisville, Louisville, KY, USA
| | - M. A. Hooper
- Department of Psychological & Brain Sciences, University of Louisville, Louisville, KY, USA
- Department of Psychology, Vanderbilt University, Nashville, TN, USA
| | - C. Rodriguez Pena
- Department of Computer Science and Engineering, University of Louisville, Louisville, KY, USA
| | - D. Cohen
- Department of Psychological & Brain Sciences, University of Louisville, Louisville, KY, USA
| | - S. Allen
- Department of Electrical and Computer Engineering, University of Louisville, Louisville, KY, USA
| | - E. D. Cash
- Department of Otolaryngology-HNS and Communicative Disorders, University of Louisville School of Medicine, Louisville, KY, USA
- University of Louisville Healthcare-Brown Cancer Center, Louisville, KY, USA
| | - K. Welch
- Department of Electrical and Computer Engineering, University of Louisville, Louisville, KY, USA
| | - C. A. Levinson
- Department of Psychological & Brain Sciences, University of Louisville, Louisville, KY, USA
- Department of Pediatrics, Child and Adolescent Psychology and Psychiatry, University of Louisville, Louisville, KY, USA
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Katsiotis CS, Tikhomirov E, Strømme M, Lindh J, Welch K. Combinatorial 3D printed dosage forms for a two-step and controlled drug release. Eur J Pharm Sci 2023:106486. [PMID: 37277047 DOI: 10.1016/j.ejps.2023.106486] [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: 02/01/2023] [Revised: 05/15/2023] [Accepted: 06/02/2023] [Indexed: 06/07/2023]
Abstract
Fused deposition modeling (FDM) and selective laser sintering (SLS) are two of the most employed additive manufacturing (AM) techniques within the pharmaceutical research field. Despite the numerous advantages of different AM methods, their respective drawbacks have yet to be fully addressed, and therefore combinatorial systems are starting to emerge. In the present study, hybrid systems comprising SLS inserts and a two-compartment FDM shell are developed to achieve controlled release of the model drug theophylline. Via the use of SLS a partial amorphization of the drug is demonstrated, which can be advantageous in the case of poorly soluble drugs, and it is shown that sintering parameters can regulate the dosage and release kinetics of the drug from the inserts. Furthermore, via different combinations of inserts within the FDM-printed shell, various drug release patterns, such as a two-step or prolonged release, can be achieved. The study serves as a proof of concept, highlighting the advantages of combining two AM techniques, both to overcome their respective shortcomings and to develop modular and highly tunable drug delivery devices.
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Affiliation(s)
- Christos S Katsiotis
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Uppsala University, Box 35, Uppsala SE-751 03, Sweden.
| | - Evgenii Tikhomirov
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Uppsala University, Box 35, Uppsala SE-751 03, Sweden.
| | - Maria Strømme
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Uppsala University, Box 35, Uppsala SE-751 03, Sweden.
| | - Jonas Lindh
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Uppsala University, Box 35, Uppsala SE-751 03, Sweden.
| | - Ken Welch
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Uppsala University, Box 35, Uppsala SE-751 03, Sweden.
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Nagendra A, Orleans-Pobee M, Vincent C, Padgett J, Merritt C, Crosby C, Welch K, Roberts SO, Penn DL. The representation of authors of color in schizophrenia research articles published in high-impact psychiatric journals. Schizophr Res 2023; 253:75-78. [PMID: 36216712 DOI: 10.1016/j.schres.2022.08.021] [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] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 07/06/2022] [Accepted: 08/23/2022] [Indexed: 11/16/2022]
Abstract
OBJECTIVE We evaluate how often scholars of color publish papers on schizophrenia in high-impact psychiatric journals, and whether they are more likely than white authors to prioritize race/ethnicity as a primary variable of interest in analyses. METHODS Prior work categorized the types of ethnoracial analyses reported in 474 papers about schizophrenia published in high-impact psychiatric journals between 2014 and 2016. In this study, the photographs of the first and last author for each paper were coded as "person of color" (POC) or "white". Additionally, each author was asked to self-report their race and ethnicity. The percentage of papers published by white versus POC authors was calculated. Chi-square analyses tested the hypotheses that (a) white scholars are more likely than POC scholars to conduct any sort of racial analysis; (b) POC scholars are more likely to conduct primary analyses by race/ethnicity; and (c) white scholars are more likely to analyze race/ethnicity as extraneous variables. RESULTS Eighteen percent of papers were published by POC first authors, and 17% were published by POC last authors. There were minimal differences in the types of analyses conducted by POC and white authors. Self-reported race/ethnicity showed that Asian scholars were the most highly represented within POC authors (9% of respondents), but only 3% of authors identified as Hispanic/Latinx and none identified as Black or Indigenous American. CONCLUSIONS People of color are underrepresented as authors in US-based schizophrenia research published in high-impact journals. Culturally-informed mentorship as well as prioritization of race/ethnicity in funding structures are important to increase representation of POC authors.
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Affiliation(s)
- A Nagendra
- Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA.
| | - M Orleans-Pobee
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - C Vincent
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - J Padgett
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - C Merritt
- Department of Psychology, Center for Comparative Studies in Race and Ethnicity, Stanford University, USA
| | - C Crosby
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - K Welch
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - S O Roberts
- Department of Psychology, Center for Comparative Studies in Race and Ethnicity, Stanford University, USA
| | - D L Penn
- Department of Psychology and Neuroscience, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA; Australian Catholic University, School of Behavioural and Health Sciences, Melbourne, VIC, Australia
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Katsiotis CS, Strømme M, Welch K. Processability of mesoporous materials in fused deposition modeling for drug delivery of a model thermolabile drug. Int J Pharm X 2022; 5:100149. [PMID: 36593988 PMCID: PMC9804103 DOI: 10.1016/j.ijpx.2022.100149] [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] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 12/13/2022] [Accepted: 12/16/2022] [Indexed: 12/23/2022] Open
Abstract
The incorporation of drug-loaded mesoporous materials in dosage forms prepared with fused deposition modeling (FDM) has shown the potential to solve challenges relating to additive manufacturing techniques, such as the stability of poorly-soluble drugs in the amorphous state. However, the addition of these non-melting mesoporous materials significantly affects the mechanical properties of the filament used in FDM, which in turn affects the printability of the feedstock material. Therefore, in this study a full-factorial experimental design was utilized to investigate different processing parameters of the hot melt extrusion process, their effect on various mechanical properties and the potential correlation with the filaments' printability. The thermolabile, poorly-soluble drug ibuprofen was utilized as a model drug to assess the potential of two mesoporous materials, Mesoporous Magnesium Carbonate (MMC) and a silica-based material (MCM-41), to thermally protect the loaded drug. Factorial and principal components analysis displayed a correlation between non-printable MCM-41 filaments and their mechanical properties where printable filaments had a maximum stress >7.5 MPa and a Young's modulus >83 MPa. For MMC samples there was no clear correlation, which was in large part attributed to the filaments' inconsistencies and imperfections. Finally, both mesoporous materials displayed a thermal protective feature, as the decomposition due to the thermal degradation of a significant portion of the thermolabile drug was shifted to higher temperatures post-loading. This highlights the potential capability of such a system to be implemented for thermosensitive drugs in FDM applications.
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Phipps D, Southworth E, Welch K, Carey E. Relationship Between Adverse Childhood Experiences and Vulvodynia Pain Scores. J Sex Med 2022. [DOI: 10.1016/j.jsxm.2022.05.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Afewerki S, Wang X, Ruiz-Esparza GU, Tai CW, Kong X, Zhou S, Welch K, Huang P, Bengtsson R, Xu C, Strømme M. Combined Catalysis for Engineering Bioinspired, Lignin-Based, Long-Lasting, Adhesive, Self-Mending, Antimicrobial Hydrogels. ACS Nano 2020; 14:17004-17017. [PMID: 33306909 DOI: 10.1021/acsnano.0c06346] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The engineering of multifunctional biomaterials using a facile sustainable methodology that follows the principles of green chemistry is still largely unexplored but would be very beneficial to the world. Here, the employment of catalytic reactions in combination with biomass-derived starting materials in the design of biomaterials would promote the development of eco-friendly technologies and sustainable materials. Herein, we disclose the combination of two catalytic cycles (combined catalysis) comprising oxidative decarboxylation and quinone-catechol redox catalysis for engineering lignin-based multifunctional antimicrobial hydrogels. The bioinspired design mimics the catechol chemistry employed by marine mussels in nature. The resultant multifunctional sustainable hydrogels (1) are robust and elastic, (2) have strong antimicrobial activity, (3) are adhesive to skin tissue and various other surfaces, and (4) are able to self-mend. A systematic characterization was carried out to fully elucidate and understand the facile and efficient catalytic strategy and the subsequent multifunctional materials. Electron paramagnetic resonance analysis confirmed the long-lasting quinone-catechol redox environment within the hydrogel system. Initial in vitro biocompatibility studies demonstrated the low toxicity of the hydrogels. This proof-of-concept strategy could be developed into an important technological platform for the eco-friendly, bioinspired design of other multifunctional hydrogels and their use in various biomedical and flexible electronic applications.
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Affiliation(s)
- Samson Afewerki
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Ångström Laboratory, Uppsala University, Box 35, 751 03 Uppsala, Sweden
| | - Xichi Wang
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
- Division of Health Sciences and Technology, Harvard University - Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, United States
| | - Guillermo U Ruiz-Esparza
- Division of Engineering in Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, United States
- Division of Health Sciences and Technology, Harvard University - Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, United States
| | - Cheuk-Wai Tai
- Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, SE-10691 Stockholm, Sweden
| | - Xueying Kong
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Ångström Laboratory, Uppsala University, Box 35, 751 03 Uppsala, Sweden
| | - Shengyang Zhou
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Ångström Laboratory, Uppsala University, Box 35, 751 03 Uppsala, Sweden
| | - Ken Welch
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Ångström Laboratory, Uppsala University, Box 35, 751 03 Uppsala, Sweden
| | - Ping Huang
- Department of Chemistry, Ångström Laboratory, Uppsala University, Box 35, 751 03 Uppsala, Sweden
| | - Rhodel Bengtsson
- Department of Materials Science and Engineering, Applied Mechanics, Ångström Laboratory, Uppsala University, Box 35, 751 03 Uppsala, Sweden
| | - Chao Xu
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Ångström Laboratory, Uppsala University, Box 35, 751 03 Uppsala, Sweden
| | - Maria Strømme
- Division of Nanotechnology and Functional Materials, Department of Materials Science and Engineering, Ångström Laboratory, Uppsala University, Box 35, 751 03 Uppsala, Sweden
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Affiliation(s)
- Jiaojiao Yang
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China
- Department of Engineering Science, Uppsala University, Uppsala SE-75121, Sweden
| | - Jun Luo
- Department of Engineering Science, Uppsala University, Uppsala SE-75121, Sweden
- College of Polymer Science and Engineering, Sichuan University, Chengdu 610065, China
| | - Haidong Liu
- Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala SE-75121, Sweden
| | - Liyang Shi
- State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, Hunan University, Changsha 410082, China
| | - Ken Welch
- Department of Engineering Science, Uppsala University, Uppsala SE-75121, Sweden
| | - Zhaohui Wang
- Department of Chemistry-Ångström Laboratory, Uppsala University, Uppsala SE-75121, Sweden
- College of Materials Science and Engineering, Hunan University, Changsha 410082, China
| | - Maria Strømme
- Department of Engineering Science, Uppsala University, Uppsala SE-75121, Sweden
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Yang J, Chen S, Luo J, Persson C, Cölfen H, Welch K, Strømme M. Multifunctional Polymer-Free Mineral Plastic Adhesives Formed by Multiple Noncovalent Bonds. ACS Appl Mater Interfaces 2020; 12:7403-7410. [PMID: 31958949 DOI: 10.1021/acsami.9b17253] [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] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Supramolecular adhesives have attracted a great deal of attention in recent years, resulting in their development for different applications. However, creating supramolecular adhesives with reversible and reusable properties is still a challenge. Here, a synthesis route to obtain supramolecular adhesives is presented in which no polymeric compounds are involved in the preparation. The adhesive is formed by intermolecular coulomb forces between amorphous magnesium carbonate nanoparticles and the low-molecular-weight drug ibuprofen, which results in an amorphous composite material that is transparent, shapeable, stretchable, and self-healing, making it reusable. It is demonstrated that this hybrid material provides a simple means of gluing a wide variety of materials, including metals, glass, paper, and plastics, and that is reversible and possesses reusability. The material disrupts the traditional concept of polymer-based adhesives and may be used as a sustainable mineral plastic in applications such as 3D printing.
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Affiliation(s)
- Jiaojiao Yang
- State Key Laboratory of Oral Diseases, West China Hospital of Stomatology , Sichuan University , Chengdu , 610041 , P. R. China.,Nanotechnology and Functional Materials, Department of Engineering Sciences , Uppsala University , Uppsala , 75121 , Sweden
| | - Song Chen
- Physical Chemistry , University of Konstanz , Universitätsstraße 10 , Konstanz , 78457 , Germany
| | - Jun Luo
- Applied Materials Sciences, Department of Engineering Sciences , Uppsala University , Uppsala , 75212 , Sweden
| | - Cecilia Persson
- Applied Materials Sciences, Department of Engineering Sciences , Uppsala University , Uppsala , 75212 , Sweden
| | - Helmut Cölfen
- Physical Chemistry , University of Konstanz , Universitätsstraße 10 , Konstanz , 78457 , Germany
| | - Ken Welch
- Nanotechnology and Functional Materials, Department of Engineering Sciences , Uppsala University , Uppsala , 75121 , Sweden
| | - Maria Strømme
- Nanotechnology and Functional Materials, Department of Engineering Sciences , Uppsala University , Uppsala , 75121 , Sweden
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Janson O, Sörensen JH, Strømme M, Engqvist H, Procter P, Welch K. Evaluation of an alkali-treated and hydroxyapatite-coated orthopedic implant loaded with tobramycin. J Biomater Appl 2019; 34:699-720. [PMID: 31408413 DOI: 10.1177/0885328219867968] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Oscar Janson
- 1 Division of Materials Science, Department of Engineering Sciences, Uppsala University, Uppsala, Sweden
| | | | - Maria Strømme
- 3 Division of Nanotechnology and Functional Materials, Department of Engineering Sciences, Uppsala University, Uppsala, Sweden
| | - Håkan Engqvist
- 1 Division of Materials Science, Department of Engineering Sciences, Uppsala University, Uppsala, Sweden
| | - Philip Procter
- 1 Division of Materials Science, Department of Engineering Sciences, Uppsala University, Uppsala, Sweden
| | - Ken Welch
- 3 Division of Nanotechnology and Functional Materials, Department of Engineering Sciences, Uppsala University, Uppsala, Sweden
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Hulsart-Billström G, Janson O, Engqvist H, Welch K, Hong J. Thromboinflammation as bioactivity assessment of H 2O 2-alkali modified titanium surfaces. J Mater Sci Mater Med 2019; 30:66. [PMID: 31127371 PMCID: PMC6534515 DOI: 10.1007/s10856-019-6248-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 03/27/2019] [Indexed: 06/09/2023]
Abstract
The release of growth factors from platelets, mediated by the coagulation and the complement system, plays an important role in the bone formation around implants. This study aimed at exploring the thromboinflammatory response of H2O2-alkali soaked commercially pure titanium grade 2 discs exposed to whole human blood, as a way to assess the bioactivity of the discs. Commercially pure titanium grade 2 discs were modified by soaking in H2O2, NaOH and Ca(OH)2. The platelet aggregation, coagulation activation and complement activation was assessed by exposing the discs to fresh whole blood from human donors. The platelet aggregation was examined by a cell counter and the coagulation and complement activation were assessed by ELISA-measurements of the concentration of thrombin-antithrombin complex, C3a and terminal complement complex. The modified surface showed a statistically significant increased platelet aggregation, coagulation activation and complement activation compared to unexposed blood. The surface also showed a statistically significant increase of coagulation activation compared to PVC. The results of this study showed that the H2O2-alkali soaked surfaces induced a thromboinflammatory response that indicates that the surfaces are bioactive.
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Affiliation(s)
- Gry Hulsart-Billström
- Department of Engineering Sciences, Division of Applied Material Science, Uppsala University, 751 21, Uppsala, Sweden
| | - Oscar Janson
- Department of Engineering Sciences, Division of Applied Material Science, Uppsala University, 751 21, Uppsala, Sweden
| | - Håkan Engqvist
- Department of Engineering Sciences, Division of Applied Material Science, Uppsala University, 751 21, Uppsala, Sweden
| | - Ken Welch
- Department of Engineering Sciences, Division of Nanotechnology and Functional Materials, Uppsala University, 751 21, Uppsala, Sweden
| | - Jaan Hong
- Department of Immunology, Genetics and Pathology, Rudbeck Laboratory C5, Uppsala University, 75185, Uppsala, Sweden.
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Rodriguez E, Aguilar J, Marie JS, Scheuerlein K, Welch K, Patel P, Rilling W, Tutton S, Hieb R, White S, Hohenwalter E. Abstract No. 576 Standardizing after-visit summary instructions to improve patient satisfaction scores. J Vasc Interv Radiol 2019. [DOI: 10.1016/j.jvir.2018.12.657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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13
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Yang J, Alvebratt C, Lu X, Bergström CA, Strømme M, Welch K. Amorphous magnesium carbonate nanoparticles with strong stabilizing capability for amorphous ibuprofen. Int J Pharm 2018; 548:515-521. [DOI: 10.1016/j.ijpharm.2018.07.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 07/03/2018] [Accepted: 07/04/2018] [Indexed: 01/22/2023]
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Welch K, Aguilar J, Marie JS, Scheuerlein K, Patel P, Hieb R, Tutton S, Rilling W, White S, Hohenwalter E. Abstract No. 709 Quality improvement in interventional radiology: techniques to improve patient satisfaction. J Vasc Interv Radiol 2018. [DOI: 10.1016/j.jvir.2018.01.754] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Imoto Y, Kato A, Takabayashi T, Sakashita M, Norton JE, Suh LA, Carter RG, Weibman AR, Hulse KE, Stevens W, Harris KE, Peters AT, Grammer LC, Tan BK, Welch K, Conley DB, Kern RC, Fujieda S, Schleimer RP. Short-chain fatty acids induce tissue plasminogen activator in airway epithelial cells via GPR41&43. Clin Exp Allergy 2018; 48:544-554. [PMID: 29431874 DOI: 10.1111/cea.13119] [Citation(s) in RCA: 27] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 11/30/2017] [Accepted: 12/22/2017] [Indexed: 12/11/2022]
Abstract
BACKGROUND Chronic rhinosinusitis (CRS) is a heterogeneous chronic inflammatory disease generally divided based on the presence or absence of nasal polyps (NPs). One of the features of NPs is excessive fibrin deposition, which is associated with down-regulation of tissue plasminogen activator (t-PA) in NPs. As t-PA is expressed in epithelial cells, and epithelium is readily accessible to topical therapies, identifying compounds that can mediate the induction of t-PA would be a potential new strategy for the treatment of NPs. OBJECTIVE The objective of this study was to determine whether short-chain fatty acids (SCFAs) can induce t-PA in airway epithelial cells via their known receptors GPR41 and GPR43. METHODS We performed immunohistochemistry (IHC) to determine whether receptors for SCFAs, known as G protein-coupled receptor 41/free fatty acid receptor 3 (GPR41/FFAR3) and GPR43/FFAR2, are expressed in nasal tissue. Primary normal human bronchial epithelial (NHBE) cells were stimulated with different concentrations of SCFAs to test induction of t-PA, which was analysed by expression of mRNA and protein. Mediation of responses by SCFA receptors was evaluated by specific receptor gene silencing with siRNA. RESULTS Immunohistochemistry study revealed that airway epithelial cells expressed GPR41 and GPR43. Acetic acid, propionic acid, butyric acid and valeric acid significantly induced t-PA expression from two- to tenfolds. The strongest inducer of t-PA from NHBE cells was propionic acid; cells stimulated with propionic acid released t-PA into the supernatant in its active form. Gene silencing of GPR41 and GPR43 revealed that induction of t-PA by SCFAs was dependent upon both GPR41 and GPR43. CONCLUSIONS AND CLINICAL RELEVANCE Short-chain fatty acids were shown to induce airway epithelial cell expression of t-PA via GPR41 and GPR43. Topical delivery of potent compounds that activate these receptors may have value by reducing fibrin deposition and shrinking nasal polyp growth.
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Affiliation(s)
- Y Imoto
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.,Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - A Kato
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - T Takabayashi
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - M Sakashita
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - J E Norton
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - L A Suh
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - R G Carter
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - A R Weibman
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - K E Hulse
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - W Stevens
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - K E Harris
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - A T Peters
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - L C Grammer
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - B K Tan
- Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - K Welch
- Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - D B Conley
- Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - R C Kern
- Department of Otolaryngology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - S Fujieda
- Department of Otorhinolaryngology Head and Neck Surgery, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | - R P Schleimer
- Division of Allergy and Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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Basu A, Heitz K, Strømme M, Welch K, Ferraz N. Ion-crosslinked wood-derived nanocellulose hydrogels with tunable antibacterial properties: Candidate materials for advanced wound care applications. Carbohydr Polym 2018; 181:345-350. [DOI: 10.1016/j.carbpol.2017.10.085] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 10/10/2017] [Accepted: 10/24/2017] [Indexed: 10/18/2022]
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Saad MF, Parvaresh A, Carrier J, Lafrenière A, Bujaki B, Benoit A, Lalande S, Welch K, De Koninck JM, Douglass A, Lee E, Busby K, Robillard R. 1088 HEART RATE SLEEP PROFILE: A NEW BIOMARKER FOR DEPRESSION? Sleep 2017. [DOI: 10.1093/sleepj/zsx050.1087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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18
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Soininen AJ, Appavou MS, Frykstrand S, Welch K, Khaneft M, Kriele A, Bellissent-Funel MC, Strømme M, Wuttke J. Dynamics of water confined in mesoporous magnesium carbonate. J Chem Phys 2016; 145:234503. [DOI: 10.1063/1.4971285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Antti J. Soininen
- Jülich Centre for Neutron Science at MLZ, Forschungszentrum Jülich GmbH, Lichtenbergstraße 1, 85747 Garching, Germany
- Institut Laue-Langevin, 71 Avenue des Martyrs, 38042 Grenoble, France
| | - Marie-Sousai Appavou
- Jülich Centre for Neutron Science at MLZ, Forschungszentrum Jülich GmbH, Lichtenbergstraße 1, 85747 Garching, Germany
| | - Sara Frykstrand
- Division for Nanotechnology and Functional Materials, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, P.O. Box 534, 75121 Uppsala, Sweden
| | - Ken Welch
- Division for Nanotechnology and Functional Materials, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, P.O. Box 534, 75121 Uppsala, Sweden
| | - Marina Khaneft
- Jülich Centre for Neutron Science at MLZ, Forschungszentrum Jülich GmbH, Lichtenbergstraße 1, 85747 Garching, Germany
| | - Armin Kriele
- German Engineering Materials Science Centre (GEMS) at MLZ, Helmholtz-Zentrum Geesthacht GmbH, Lichtenbergstrasse 1, 85747 Garching, Germany
| | | | - Maria Strømme
- Division for Nanotechnology and Functional Materials, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, P.O. Box 534, 75121 Uppsala, Sweden
| | - Joachim Wuttke
- Jülich Centre for Neutron Science at MLZ, Forschungszentrum Jülich GmbH, Lichtenbergstraße 1, 85747 Garching, Germany
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Welch K, Latifzada MA, Frykstrand S, Strømme M. Investigation of the Antibacterial Effect of Mesoporous Magnesium Carbonate. ACS Omega 2016; 1:907-914. [PMID: 30023495 PMCID: PMC6044671 DOI: 10.1021/acsomega.6b00124] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 10/21/2016] [Indexed: 06/01/2023]
Abstract
Mesoporous magnesium carbonate (MMC) was first presented in 2013, and this material is currently under consideration for use in a number of biotechnological applications including topical formulations. This study presents the first evaluation of the antibacterial properties of the material with mesoporous silica and two other magnesium-containing powder materials used as references. All powder materials in this study are sieved to achieve a particle size distribution between 25 and 75 μm. The Gram-positive bacterium Staphylococcus epidermidis is used as the model bacterium due to its prevalence on human skin, its likelihood of developing resistance to antibiotics, for example, from routine exposure to antibiotics secreted in sweat, and because it is found inside affected acne vulgaris pores. Quantification of bacterial viability using a metabolic activity assay with resazurin as the fluorescent indicator shows that MMC exerts a strong antibacterial effect on the bacteria and that alkalinity accounts for the major part of this effect. The results open up for further development of MMC in on-skin applications where bacterial growth inhibition without using antibiotics is deemed favorable.
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Zhang P, Zardán Gómez de la Torre T, Welch K, Bergström C, Strømme M. Supersaturation of poorly soluble drugs induced by mesoporous magnesium carbonate. Eur J Pharm Sci 2016; 93:468-74. [DOI: 10.1016/j.ejps.2016.08.059] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Revised: 08/25/2016] [Accepted: 08/29/2016] [Indexed: 11/15/2022]
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Barnes D, Vande Slunt E, Wilfert M, Welch K, Jakubowski S, Aguilar BSN J, Timm Z, Bonlender K, Proulx M, Roessler A, Scheuerlein K, Dembny H, Anderson N, Weithaus M, Strycker A, Rodriguez E, White S. Cost effective management of short-dated inventory in interventional radiology. J Vasc Interv Radiol 2016. [DOI: 10.1016/j.jvir.2015.12.693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Unosson E, Morgenstern M, Engqvist H, Welch K. In vitro antibacterial properties and UV induced response from Staphylococcus epidermidis on Ag/Ti oxide thin films. J Mater Sci Mater Med 2016; 27:49. [PMID: 26758896 DOI: 10.1007/s10856-015-5662-5] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 12/28/2015] [Indexed: 06/05/2023]
Abstract
Implanted materials are susceptible to bacterial colonization and biofilm formation, which can result in severe infection and lost implant function. UV induced photocatalytic disinfection on TiO2 and release of Ag(+) ions are two promising strategies to combat such events, and can be combined for improved efficiency. In the current study, a combinatorial physical vapor deposition technique was utilized to construct a gradient coating between Ag and Ti oxide, and the coating was evaluated for antibacterial properties in darkness and under UV light against Staphylococcus epidermidis. The findings revealed a potent antibacterial effect in darkness due to Ag(+) release, with near full elimination (97%) of viable bacteria and visible cell lysis on Ag dominated surfaces. The photocatalytic activity, however, was demonstrated poor due to low TiO2 crystallinity, and UV light irradiation of the coating did not contribute to the antibacterial effect. On the contrary, bacterial viability was in several instances higher after UV illumination, proposing a UV induced SOS response from the bacteria that limited the reduction rate during Ag(+) exposure. Such secondary effects should thus be considered in the development of multifunctional coatings that rely on UV activation.
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Affiliation(s)
- Erik Unosson
- Division of Applied Materials Science, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, Box 534, 751 21, Uppsala, Sweden.
| | - Matthias Morgenstern
- Division of Applied Materials Science, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, Box 534, 751 21, Uppsala, Sweden
| | - Håkan Engqvist
- Division of Applied Materials Science, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, Box 534, 751 21, Uppsala, Sweden
| | - Ken Welch
- Division of Nanotechnology and Functional Materials, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, Box 534, 751 21, Uppsala, Sweden
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Abstract
In this chapter we review key psychologic theories that have been mooted as possible explanations for the etiology of functional neurologic symptoms, conversion disorder, and hysteria. We cover Freudian psychoanalysis and later object relations and attachment theories, social theories, illness behavior, classic and operant conditioning, social learning theory, self-regulation theory, cognitive-behavioral theories, and mindfulness. Dissociation and modern cognitive neuroscience theories are covered in other chapters in this series and, although of central importance, are omitted from this chapter. Our aim is an overview with the emphasis on breadth of coverage rather than depth.
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Affiliation(s)
- A Carson
- Departments of Clinical Neurosciences and of Rehabilitation Medicine, NHS Lothian and Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK.
| | - L Ludwig
- Departments of Clinical Neurosciences and of Rehabilitation Medicine, NHS Lothian and Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
| | - K Welch
- Departments of Clinical Neurosciences and of Rehabilitation Medicine, NHS Lothian and Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK
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Poposki JA, Peterson S, Welch K, Schleimer RP, Hulse KE, Peters AT, Norton J, Suh LA, Carter R, Harris KE, Grammer LC, Tan BK, Chandra RK, Conley DB, Kern RC, Kato A. Elevated presence of myeloid dendritic cells in nasal polyps of patients with chronic rhinosinusitis. Clin Exp Allergy 2015; 45:384-93. [PMID: 25469646 DOI: 10.1111/cea.12471] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [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: 08/09/2014] [Revised: 11/23/2014] [Accepted: 11/28/2014] [Indexed: 12/14/2022]
Abstract
BACKGROUND Although chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by Th2 inflammation, the mechanism underlying the onset and amplification of this inflammation has not been fully elucidated. Dendritic cells (DCs) are major antigen-presenting cells, central inducers of adaptive immunity and critical regulators of many inflammatory diseases. However, the presence of DCs in CRS, especially in nasal polyps (NPs), has not been extensively studied. OBJECTIVE The objective of this study was to characterize DC subsets in CRS. METHODS We used real-time PCR to assess the expression of mRNA for markers of myeloid DCs (mDCs; CD1c), plasmacytoid DCs (pDCs; CD303) and Langerhans cells (LCs; CD1a, CD207) in uncinate tissue (UT) from controls and patients with CRS as well as in NP. We assayed the presence of DCs by immunohistochemistry and flow cytometry. RESULTS Compared to UT from control subjects (n = 15) and patients with CRS without NP (CRSsNP) (n = 16) and CRSwNP (n = 17), mRNAs for CD1a and CD1c were significantly elevated in NPs (n = 29). In contrast, CD207 mRNA was not elevated in NPs. Immunohistochemistry showed that CD1c(+) cells but not CD303(+) cells were significantly elevated in NPs compared to control subjects or patients with CRSsNP. Flow cytometric analysis showed that CD1a(+) cells in NPs might be a subset of mDC1s and that CD45(+) CD19(-) CD1c(+) CD11c(+) CD141(-) CD303(-) HLA-DR(+) mDC1s and CD45(+) CD19(-) CD11c(+) CD1c(-) CD141(high) HLA-DR(+) mDC2s were significantly elevated in NPs compared to UT from controls and CRSsNP, but CD45(+) CD11c(-) CD303(+) HLA-DR(+) pDCs were only elevated in NPs compared to control UT. CONCLUSION AND CLINICAL RELEVANCE Myeloid DCs are elevated in CRSwNP, especially in NPs. Myeloid DCs thus may indirectly contribute to the inflammation observed in CRSwNP.
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Affiliation(s)
- J A Poposki
- Division of Allergy-Immunology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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25
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Unosson E, Rodriguez D, Welch K, Engqvist H. Reactive combinatorial synthesis and characterization of a gradient Ag-Ti oxide thin film with antibacterial properties. Acta Biomater 2015; 11:503-10. [PMID: 25281786 DOI: 10.1016/j.actbio.2014.09.048] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 09/22/2014] [Accepted: 09/26/2014] [Indexed: 01/12/2023]
Abstract
The growing demand for orthopedic and dental implants has spurred researchers to develop multifunctional coatings, combining tissue integration with antibacterial features. A possible strategy to endow titanium (Ti) with antibacterial properties is by incorporating silver (Ag), but designing a structure with adequate Ag(+) release while maintaining biocompatibility has been shown difficult. To further explore the composition-structure-property relationships between Ag and Ti, and its effects against bacteria, this study utilized a combinatorial approach to manufacture and test a single sample containing a binary Ag-Ti oxide gradient. The sample, sputter-deposited in a reactive (O2) environment using a custom-built combinatorial physical vapor deposition system, was shown to be effective against Staphylococcus aureus with viability reductions ranging from 17 to above 99%, depending on the amount of Ag(+) released from its different parts. The Ag content along the gradient ranged from 35 to 62 wt.%, but it was found that structural properties such as varied porosity and degree of crystallinity, rather than the amount of incorporated Ag, governed the Ag(+) release and resulting antibacterial activity. The coating also demonstrated in vitro apatite-forming abilities, where structural variety along the sample was shown to alter the hydrophilic behavior, with the degree of hydroxyapatite deposition varying accordingly. By means of combinatorial synthesis, a single gradient sample was able to display intricate compositional and structural features affecting its biological response, which would otherwise require a series of coatings. The current findings suggest that future implant coatings incorporating Ag as an antibacterial agent could be structurally enhanced to better suit clinical requirements.
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26
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Sörensen JH, Dürselen L, Welch K, Sörensen TC, Procter P, Engqvist H, Strømme M, Ignatius A, Steckel H. Biomimetic Hydroxyapatite Coated Titanium Screws Demonstrate Rapid Implant Stabilization and Safe Removal <i>In-Vivo</i>. ACTA ACUST UNITED AC 2015. [DOI: 10.4236/jbnb.2015.61003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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27
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Zaborowska M, Welch K, Brånemark R, Khalilpour P, Engqvist H, Thomsen P, Trobos M. Bacteria-material surface interactions: methodological development for the assessment of implant surface induced antibacterial effects. J Biomed Mater Res B Appl Biomater 2014; 103:179-87. [PMID: 24816674 DOI: 10.1002/jbm.b.33179] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [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: 12/20/2013] [Revised: 03/19/2014] [Accepted: 04/12/2014] [Indexed: 01/09/2023]
Abstract
The choice of material for implanted prostheses is of great importance concerning bacterial colonization and biofilm formation. Consequently, methods to investigate bacterial behavior are needed in order to develop new infection resistant surfaces. In this study, different methodological setups were used to evaluate the antimicrobial effect of photocatalytic titanium oxide and silver surfaces. Biofilm formation and eradication under static and dynamic culture conditions were studied with the use of the following analytical techniques: viable colony-forming unit (CFU) counting, imprinting, fluorescence, and bioluminescence. The present study demonstrates that different methods are needed in order to evaluate the prophylactic and treatment effects on planktonic and biofilm bacteria and to assess the antimicrobial effect of different surface treatments/coatings. Choosing the right antibacterial testing model for the specific application is also of great importance. Both in situ approaches and indirect methods provide valuable complementary information.
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Affiliation(s)
- Magdalena Zaborowska
- Department of Biomaterials, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden; BIOMATCELL VINN Excellence Center of Biomaterials and Cell Therapy, Gothenburg, Sweden
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28
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Russell C, Welch K, Jarvius J, Cai Y, Brucas R, Nikolajeff F, Svedlindh P, Nilsson M. Gold nanowire based electrical DNA detection using rolling circle amplification. ACS Nano 2014; 8:1147-53. [PMID: 24433087 PMCID: PMC3936482 DOI: 10.1021/nn4058825] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We present an electrical sensor that uses rolling circle amplification (RCA) of DNA to stretch across the gap between two electrodes, interact with metal nanoparticle seeds to generate an electrically conductive nanowire, and produce electrical signals upon detection of specific target DNA sequences. RCA is a highly specific molecular detection mechanism based on DNA probe circularization. With this technique, long single-stranded DNA with simple repetitive sequences are produced. Here we show that stretched RCA products can be metalized using silver or gold solutions to form metal wires. Upon metallization, the resistance drops from TΩ to kΩ for silver and to Ω for gold. Metallization is seeded by gold nanoparticles aligned along the single-stranded DNA product through hybridization of functionalized oligonucleotides. We show that combining RCA with electrical DNA detection produces results in readout with very high signal-to-noise ratio, an essential feature for sensitive and specific detection assays. Finally, we demonstrate detection of 10 ng of Escherichia coli genomic DNA using the sensor concept.
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Affiliation(s)
- Camilla Russell
- Department of Immunology, Genetics and Pathology, Uppsala University, SE-751 85 Uppsala, Sweden
| | - Ken Welch
- Department of Engineering Sciences, Uppsala University, SE-751 21 Uppsala, Sweden
| | | | - Yixiao Cai
- Department of Engineering Sciences, Uppsala University, SE-751 21 Uppsala, Sweden
| | - Rimantas Brucas
- Department of Engineering Sciences, Uppsala University, SE-751 21 Uppsala, Sweden
| | - Fredrik Nikolajeff
- Department of Engineering Sciences, Uppsala University, SE-751 21 Uppsala, Sweden
| | - Peter Svedlindh
- Department of Engineering Sciences, Uppsala University, SE-751 21 Uppsala, Sweden
| | - Mats Nilsson
- Department of Immunology, Genetics and Pathology, Uppsala University, SE-751 85 Uppsala, Sweden
- Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University114 18 Stockholm, Sweden
- Address correspondence to
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29
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Cai Y, Strømme M, Welch K. Disinfection Kinetics and Contribution of Reactive Oxygen Species When Eliminating Bacteria with TiO<sub>2</sub> Induced Photocatalysis. ACTA ACUST UNITED AC 2014. [DOI: 10.4236/jbnb.2014.53024] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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30
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Abstract
Bioactivity of resin–TiO2 nanocomposite induced by TiO2 photocatalysis under UV irradiation.
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Affiliation(s)
- Yanling Cai
- Nanotechnology and Functional Materials
- The Ångström Laboratory
- Uppsala University
- Uppsala, Sweden
| | - Maria Strømme
- Nanotechnology and Functional Materials
- The Ångström Laboratory
- Uppsala University
- Uppsala, Sweden
| | - Peng Zhang
- Nanotechnology and Functional Materials
- The Ångström Laboratory
- Uppsala University
- Uppsala, Sweden
| | - Håkan Engqvist
- Applied Materials Science
- The Ångström Laboratory
- Uppsala University
- Uppsala, Sweden
| | - Ken Welch
- Nanotechnology and Functional Materials
- The Ångström Laboratory
- Uppsala University
- Uppsala, Sweden
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31
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Ghaziuddin M, Welch K. The michigan autism spectrum questionnaire: a rating scale for high-functioning autism spectrum disorders. Autism Res Treat 2013; 2013:708273. [PMID: 24381759 PMCID: PMC3870086 DOI: 10.1155/2013/708273] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 10/02/2013] [Accepted: 10/21/2013] [Indexed: 11/20/2022]
Abstract
Although the DSM-5 has recently created a single category of autism spectrum disorder (ASD), delineation of its putative subtypes remains clinically useful. For this process, screening instruments should ideally be brief, simple, and easily available. The aim of this study is to describe the validity of one such instrument. We administered the Michigan Autism Spectrum Questionnaire (MASQ), a 10-item questionnaire, to 42 patients with ASD (age range 6-13 years, mean 9.7 years, SD 2.5, one female) and 18 patients with other psychiatric disorders (age range 6-17 years, mean 11.7 years, SD 3.8, 6 females). Responses to each item were scored from 0 to 4 yielding a total score of 30. Patients with intellectual disability were excluded. As a group, patients with ASD scored higher than those with other psychiatric disorders (Chi-square test with 1 df = 16.019, P < 0.0001). Within the ASD group, a linear discriminant analysis found that the best cut-off points were 22 or above for Asperger syndrome, 14 to 21 for autism/PDDNOS, and less than 14 for those with other psychiatric disorders. We propose that the MASQ can be used as a brief measure to screen high-functioning ASD from other psychiatric disorders and to identify its possible subtypes.
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Affiliation(s)
- M Ghaziuddin
- Department of Psychiatry, University of Michigan Medical Center, Plymouth Road, Ann Arbor, MI 48109-0277, USA
| | - K Welch
- Center for Statistical Consultation and Research (CSCAR), University of Michigan Medical Center, Plymouth Road, Ann Arbor, MI 48109-0277, USA
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Unosson E, Tsekoura EK, Engqvist H, Welch K. Synergetic inactivation of Staphylococcus epidermidis and Streptococcus mutansin a TiO2/H2O2/UV system. Biomatter 2013; 3:26727. [PMID: 24135830 DOI: 10.4161/biom.26727] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
TiO 2 photocatalysis can be used to kill surface adherent bacteria on biomaterials, and is particularly interesting for use with percutaneous implants and devices. Its efficiency and safety, however, depend on the activation energy required. This in vitro study investigates synergetic effects against the clinically relevant strains S. epidermidis and S. mutans when combining photocatalytic surfaces with H2O2. After 20 min exposure to 0.1 wt% H2O2 and UV light on TiO2 surfaces, viabilities of S. epidermidis and S. mutans were reduced by 99.7% and 98.9%, respectively. Without H2O2 the corresponding viability reduction was 86% for S. epidermidis and 65% for S. mutans. This study indicates that low concentrations of H2O2 can enhance the efficiency of photocatalytic TiO2 surfaces, which could potentially improve current techniques used for decontamination and debridement of TiO2 coated biomedical implants and devices.
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Affiliation(s)
- Erik Unosson
- Division of Applied Materials Science; Department of Engineering Sciences; The Ångström Laboratory; Uppsala University; Uppsala, Sweden
| | - Eleni K Tsekoura
- Division of Nanotechnology and Functional Materials; Department of Engineering Sciences; The Ångström Laboratory; Uppsala University; Uppsala, Sweden
| | - Håkan Engqvist
- Division of Applied Materials Science; Department of Engineering Sciences; The Ångström Laboratory; Uppsala University; Uppsala, Sweden
| | - Ken Welch
- Division of Nanotechnology and Functional Materials; Department of Engineering Sciences; The Ångström Laboratory; Uppsala University; Uppsala, Sweden
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Bond M, Pavey T, Welch K, Cooper C, Garside R, Dean S, Hyde C. Systematic review of the psychological consequences of false-positive screening mammograms. Health Technol Assess 2013; 17:1-170, v-vi. [PMID: 23540978 DOI: 10.3310/hta17130] [Citation(s) in RCA: 107] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND In the UK, women aged 50-73 years are invited for screening by mammography every 3 years. In 2009-10, more than 2.24 million women in this age group in England were invited to take part in the programme, of whom 73% attended a screening clinic. Of these, 64,104 women were recalled for assessment. Of those recalled, 81% did not have breast cancer; these women are described as having a false-positive mammogram. OBJECTIVE The aim of this systematic review was to identify the psychological impact on women of false-positive screening mammograms and any evidence for the effectiveness of interventions designed to reduce this impact. We were also looking for evidence of effects in subgroups of women. DATA SOURCES MEDLINE, MEDLINE In-Process & Other Non-Indexed Citations, EMBASE, Health Management Information Consortium, Cochrane Central Register for Controlled Trials, Cochrane Database of Systematic Reviews, Centre for Reviews and Dissemination (CRD) Database of Abstracts of Reviews of Effects, CRD Health Technology Assessment (HTA), Cochrane Methodology, Web of Science, Science Citation Index, Social Sciences Citation Index, Conference Proceedings Citation Index-Science, Conference Proceeding Citation Index-Social Science and Humanities, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, Sociological Abstracts, the International Bibliography of the Social Sciences, the British Library's Electronic Table of Contents and others. Initial searches were carried out between 8 October 2010 and 25 January 2011. Update searches were carried out on 26 October 2011 and 23 March 2012. REVIEW METHODS Based on the inclusion criteria, titles and abstracts were screened independently by two reviewers. Retrieved papers were reviewed and selected using the same independent process. Data were extracted by one reviewer and checked by another. Each included study was assessed for risk of bias. RESULTS Eleven studies were found from 4423 titles and abstracts. Studies that used disease-specific measures found a negative psychological impact lasting up to 3 years. Distress increased with the level of invasiveness of the assessment procedure. Studies using instruments designed to detect clinical levels of morbidity did not find this effect. Women with false-positive mammograms were less likely to return for the next round of screening [relative risk (RR) 0.97; 95% confidence interval (CI) 0.96 to 0.98] than those with normal mammograms, were more likely to have interval cancer [odds ratio (OR) 3.19 (95% CI 2.34 to 4.35)] and were more likely to have cancer detected at the next screening round [OR 2.15 (95% CI 1.55 to 2.98)]. LIMITATIONS This study was limited to UK research and by the robustness of the included studies, which frequently failed to report quality indicators, for example failure to consider the risk of bias or confounding, or failure to report participants' demographic characteristics. CONCLUSIONS We conclude that the experience of having a false-positive screening mammogram can cause breast cancer-specific psychological distress that may endure for up to 3 years, and reduce the likelihood that women will return for their next round of mammography screening. These results should be treated cautiously owing to inherent weakness of observational designs and weaknesses in reporting. Future research should include a qualitative interview study and observational studies that compare generic and disease-specific measures, collect demographic data and include women from different social and ethnic groups.
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Affiliation(s)
- M Bond
- Peninsula Technology Assessment Group (PenTAG), University of Exeter, Exeter, UK
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Cai Y, Strømme M, Melhus A, Engqvist H, Welch K. Photocatalytic inactivation of biofilms on bioactive dental adhesives. J Biomed Mater Res B Appl Biomater 2013; 102:62-7. [PMID: 23847027 DOI: 10.1002/jbm.b.32980] [Citation(s) in RCA: 24] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 04/27/2013] [Accepted: 05/05/2013] [Indexed: 11/11/2022]
Abstract
Biofilms are the most prevalent mode of microbial life in nature and are 10-1000 times more resistant to antibiotics than planktonic bacteria. Persistent biofilm growth associated at the margin of a dental restoration often leads to secondary caries, which remains a challenge in restorative dentistry. In this work, we present the first in vitro evaluation of on-demand photocatalytic inactivation of biofilm on a novel dental adhesive containing TiO2 nanoparticles. Streptococcus mutans biofilm was cultured on this photocatalytic surface for 16 h before photocatalytic treatment with ultraviolet-A (UV-A) light. UV-A doses ranging from 3 to 43 J/cm(2) were applied to the surface and the resulting viability of biofilms was evaluated with a metabolic activity assay incorporating phenol red that provided a quantitative measure of the reduction in viability due to the photocatalytic treatments. We show that an UV-A irradiation dose of 8.4 J/cm(2) leads to one order of magnitude reduction in the number of biofilm bacteria on the surface of the dental adhesives while as much as 5-6 orders of magnitude reduction in the corresponding number can be achieved with a dose of 43 J/cm(2). This material maintains its functional properties as an adhesive in restorative dentistry while offering the possibility of a novel dental procedure in the treatment or prevention of bacterial infections via on-demand UV-A irradiation. Similar materials could be developed for the treatment of additional indications such as peri-implantits.
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Affiliation(s)
- Yanling Cai
- Nanotechnology and Functional Materials, The Ångström Laboratory, Uppsala University, Uppsala, Sweden
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Abstract
Abstract
Background: Central line-associated blood stream infection (CLABSI) rates in adult care intensive care units have been decreasing across the board. However, we continued to see just a few infections in patients whose catheters are in for >4 days. Therefore, we looked at infections associated with intraluminal contamination to help reduce our infection rate.
Methods: A protective cap trial was developed and implemented in 2 intensive care units. All of the central venous catheter and intravenous tubing access valves were covered with a protective cap saturated with alcohol. This intervention eliminated the need to wipe off intravenous access points with an alcohol swab. The study was done as a nonrandomized prospective trial occurring March 1, 2011 through February 29, 2012.
Results: During 2010, there were 4 CLABSI-related infections. By the end of the trial, we had incurred 1 catheter-associated blood stream infection. CLABSI rate reduced from 1.9 in 2010 to 0.5 during the 1-year trial period.
Conclusions: The implementation of the port protector cap system resulted in lower infection rates compared with an alcohol swab technique. Our results indicate that consistent use of the caps in tandem with strict compliance does influence CLABSI rates.
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Affiliation(s)
| | | | - Ken Welch
- Banner Estrella Medical Center, Phoenix, AZ
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Bond M, Pavey T, Welch K, Cooper C, Garside R, Dean S, Hyde C. OP37 Psychological Consequences of False-Positive Screening Mammograms in the UK: A Systematic Review. Br J Soc Med 2012. [DOI: 10.1136/jech-2012-201753.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Abstract
BACKGROUND AND OBJECTIVE The clinical efficacy of EMDs for the treatment of periodontal infrabony defects has been reported. However, recent publications have questioned the validity of results from early findings. Hence, the purpose of this study was to compare the results obtained from early and late studies when EMD was used as an adjunct in treating human intrabony defects during flap surgery. The aim of this meta-analysis was to evaluate the validity of results published from early studies compared with those published from later studies. MATERIAL AND METHODS PubMed and MEDLINE searches were performed. The evaluation period was 1997-2010 and it was divided into two groups of equal periods of time: early studies (1997-2003) and late studies (2004-2010). The clinical parameters assessed were clinical attachment level (CAL), probing pocket depth and bone gain (BG; measured as a percentage or in mm). RESULTS No statistically significant difference was found between the results obtained from early studies (1997-2003) and late studies (2004-2010) with regards to CAL gain, probing pocket depth reduction and BG. Nonetheless, both study periods showed a benefit for using EMD to treat periodontal infrabony defects when compared with the groups without EMD during open flap surgery. CONCLUSIONS The results obtained from this study failed to show any potential differences between the results published from early studies and late studies with regards to the clinical effectiveness of EMD in treating periodontal infrabony defects.
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Affiliation(s)
- V T Mueller
- Graduate Periodontics, School of Dentistry, University of Michigan, Ann Arbor, MI 48109-1078, USA
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Welch K, Cai Y, Strømme M. A method for quantitative determination of biofilm viability. J Funct Biomater 2012; 3:418-31. [PMID: 24955541 PMCID: PMC4047939 DOI: 10.3390/jfb3020418] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2012] [Revised: 05/12/2012] [Accepted: 05/22/2012] [Indexed: 12/03/2022] Open
Abstract
In this study we present a scheme for quantitative determination of biofilm viability offering significant improvement over existing methods with metabolic assays. Existing metabolic assays for quantifying viable bacteria in biofilms usually utilize calibration curves derived from planktonic bacteria, which can introduce large errors due to significant differences in the metabolic and/or growth rates of biofilm bacteria in the assay media compared to their planktonic counterparts. In the presented method we derive the specific growth rate of Streptococcus mutans bacteria biofilm from a series of metabolic assays using the pH indicator phenol red, and show that this information could be used to more accurately quantify the relative number of viable bacteria in a biofilm. We found that the specific growth rate of S. mutans in biofilm mode of growth was 0.70 h−1, compared to 1.09 h−1 in planktonic growth. This method should be applicable to other bacteria types, as well as other metabolic assays, and, for example, to quantify the effect of antibacterial treatments or the performance of bactericidal implant surfaces.
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Affiliation(s)
- Ken Welch
- Division for Nanotechnology and Functional Materials, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, Box 534, 75121 Uppsala, Sweden.
| | - Yanling Cai
- Division for Nanotechnology and Functional Materials, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, Box 534, 75121 Uppsala, Sweden.
| | - Maria Strømme
- Division for Nanotechnology and Functional Materials, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, Box 534, 75121 Uppsala, Sweden.
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Unosson E, Persson C, Welch K, Engqvist H. Photocatalytic activity of low temperature oxidized Ti-6Al-4V. J Mater Sci Mater Med 2012; 23:1173-1180. [PMID: 22391995 DOI: 10.1007/s10856-012-4602-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 02/22/2012] [Indexed: 05/31/2023]
Abstract
Numerous advanced surface modification techniques exist to improve bone integration and antibacterial properties of titanium based implants and prostheses. A simple and straightforward method of obtaining uniform and controlled TiO(2) coatings of devices with complex shapes is H(2)O(2)-oxidation and hot water aging. Based on the photoactivated bactericidal properties of TiO(2), this study was aimed at optimizing the treatment to achieve high photocatalytic activity. Ti-6Al-4V samples were H(2)O(2)-oxidized and hot water aged for up to 24 and 72 h, respectively. Degradation measurements of rhodamine B during UV-A illumination of samples showed a near linear relationship between photocatalytic activity and total treatment time, and a nanoporous coating was observed by scanning electron microscopy. Grazing incidence X-ray diffraction showed a gradual decrease in crystallinity of the surface layer, suggesting that the increase in surface area rather than anatase formation was responsible for the increase in photocatalytic activity.
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Affiliation(s)
- Erik Unosson
- Division of Applied Materials Science, Department of Engineering Sciences, The Ångström Laboratory, Uppsala University, Box 534, 751 21 Uppsala, Sweden.
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Lilja M, Welch K, Åstrand M, Engqvist H, Strømme M. Effect of deposition parameters on the photocatalytic activity and bioactivity of TiO2 thin films deposited by vacuum arc on Ti-6Al-4V substrates. J Biomed Mater Res B Appl Biomater 2012; 100:1078-85. [DOI: 10.1002/jbm.b.32674] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2011] [Revised: 12/01/2011] [Accepted: 12/03/2011] [Indexed: 11/09/2022]
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Hamilton E, Welch K, Barnhard Y, Smith S, Knox E, O'Keeffe D. 286: Unexpected effects of reducing elective inductions under 39 weeks gestation. Am J Obstet Gynecol 2012. [DOI: 10.1016/j.ajog.2011.10.304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Colquitt JL, Jones J, Harris P, Loveman E, Bird A, Clegg AJ, Baguley DM, Proops DW, Mitchell TE, Sheehan PZ, Welch K. Bone-anchored hearing aids (BAHAs) for people who are bilaterally deaf: a systematic review and economic evaluation. Health Technol Assess 2011; 15:1-200, iii-iv. [PMID: 21729632 DOI: 10.3310/hta15260] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND A bone-anchored hearing aid (BAHA) consists of a permanent titanium fixture, which is surgically implanted into the skull bone behind the ear, and a small detachable sound processor that clips onto the fixture. BAHAs are suitable for people with conductive or mixed hearing loss who cannot benefit fully from conventional hearing aids. OBJECTIVES To assess the clinical effectiveness and cost-effectiveness of BAHAs for people who are bilaterally deaf. DATA SOURCES Nineteen electronic resources, including MEDLINE, EMBASE and The Cochrane Library (inception to November 2009). Additional studies were sought from reference lists and clinical experts. REVIEW METHODS Inclusion criteria were applied by two reviewers independently. Data extraction and quality assessment were undertaken by one reviewer and checked by a second. Prospective studies of adults or children with bilateral hearing loss were eligible. Comparisons were BAHAs versus conventional hearing aids [air conduction hearing aid (ACHA) or bone conduction hearing aid (BCHA)], unaided hearing and ear surgery; and unilateral versus bilateral BAHAs. Outcomes included hearing measures, validated measures of quality of life (QoL), adverse events and measures of cost-effectiveness. For the review of cost-effectiveness, full economic evaluations were eligible. RESULTS Twelve studies were included (seven cohort pre-post studies and five cross-sectional 'audiological comparison' studies). No prospective studies comparing BAHAs with ear surgery were identified. Overall quality was rated as weak for all included studies and meta-analysis was not possible due to differences in outcome measures and patient populations. There appeared to be some audiological benefits of BAHAs compared with BCHAs and improvements in speech understanding in noise compared with ACHAs; however, ACHAs may produce better audiological results for other outcomes. The limited evidence reduces certainty. Hearing is improved with BAHAs compared with unaided hearing. Improvements in QoL with BAHAs were identified by a hearing-specific instrument but not generic QoL measures. Studies comparing unilateral with bilateral BAHAs suggested benefits of bilateral BAHAs in many, but not all, situations. Prospective case series reported between 6.1% and 19.4% loss of implants. Most participants experienced no or minor skin reactions. A decision analytic model was developed. Costs and benefits of unilateral BAHAs were estimated over a 10-year time horizon, applying discount rates of 3.5%. The incremental cost per user receiving BAHA, compared with BCHA, was £ 16,409 for children and £ 13,449 for adults. In an exploratory analysis the incremental cost per quality-adjusted life-year (QALY) gained was between £ 55,642 and £ 119,367 for children and between £ 46,628 and £ 100,029 for adults for BAHAs compared with BCHA, depending on the assumed QoL gain and proportion of each modelled cohort using their hearing aid for ≥ 8 or more hours per day. Deterministic sensitivity analysis suggested that the results were highly sensitive to the assumed proportion of people using BCHA for ≥ 8 hours per day, with very high incremental cost-effectiveness ratio values (£ 500,000-1,200,000 per QALY gained) associated with a high proportion of people using BCHA. More acceptable values (£ 15,000-37,000 per QALY gained) were associated with a low proportion of people using BCHA for ≥ 8 hours per day (compared with BAHA). LIMITATIONS The economic evaluation presented in this report is severely limited by a lack of robust evidence on the outcome of hearing aid provision. This has lead to a more restricted analysis than was originally anticipated (limited to a comparison of BAHA and BCHA). In the absence of useable QoL data, the cost-effectiveness analysis is based on potential utility gains from hearing, that been inferred using a QoL instrument rather than measures reported by hearing aid users themselves. As a result the analysis is regarded as exploratory and the reported results should be interpreted with caution. CONCLUSIONS Exploratory cost-effectiveness analysis suggests that BAHAs are unlikely to be a cost-effective option where the benefits (in terms of hearing gain and probability of using of alternative aids) are similar for BAHAs and their comparators. The greater the benefit from aided hearing and the greater the difference in the proportion of people using the hearing aid for ≥ 8 hours per day, the more likely BAHAs are to be a cost-effective option. The inclusion of other dimensions of QoL may also increase the likelihood of BAHAs being a cost-effective option. A national audit of BAHAs is needed to provide clarity on the many areas of uncertainty surrounding BAHAs. Further research into the non-audiological benefits of BAHAs, including QoL, is required.
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Affiliation(s)
- J L Colquitt
- Southampton Health Technology Assessments Centre, Southampton, UK
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Colquitt J, Loveman E, Baguley D, Mitchell T, Sheehan P, Harris P, Proops D, Jones J, Clegg A, Welch K. Bone-anchored hearing aids for people with bilateral hearing impairment: a systematic review. Clin Otolaryngol 2011; 36:419-41. [DOI: 10.1111/j.1749-4486.2011.02376.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Loveman E, Frampton GK, Shepherd J, Picot J, Cooper K, Bryant J, Welch K, Clegg A. The clinical effectiveness and cost-effectiveness of long-term weight management schemes for adults: a systematic review. Health Technol Assess 2011; 15:1-182. [PMID: 21247515 DOI: 10.3310/hta15020] [Citation(s) in RCA: 174] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
OBJECTIVE To assess the long-term clinical effectiveness and cost-effectiveness of multicomponent weight management schemes for adults in terms of weight loss and maintenance of weight loss. DATA SOURCES Bibliographic databases were searched from inception to December 2009, including the Cochrane Library, MEDLINE (Ovid), EMBASE (Ovid), and MEDLINE In-Process & Other Non-Indexed Citations. Bibliographies of related papers were screened, key conferences and symposia were searched and experts were contacted to identify additional published and unpublished references. REVIEW METHODS For the clinical effectiveness review, two reviewers independently screened titles and abstracts for eligibility. Inclusion criteria were applied to the full text of retrieved papers by one reviewer and checked by a second reviewer using a pre-piloted inclusion flow chart. The studies were long-term randomised controlled trials (RCTs) of adult participants who were classified by body mass index as overweight or obese. Interventions were multicomponent weight management programmes (including diet, physical activity and behaviour change strategies) that assessed weight measures. Programmes that involved the use of over-the-counter medicines licensed in the UK were also eligible. For the cost-effectiveness review two reviewers independently screened studies for inclusion. Cost-effectiveness, cost-utility, cost-benefit or cost-consequence analyses were eligible. Data were extracted using a standardised and pre-piloted data extraction form. The quality of included studies was assessed using standard criteria. Studies were synthesised through a narrative review with full tabulation of results. RESULTS A total of 3358 references were identified, of which 12 were included in the clinical effectiveness review. Five RCTs compared multicomponent interventions with non-active comparator groups. In general, weight loss appeared to be greater in the intervention groups than in the comparator groups. Two RCTs compared multicomponent interventions that focused on the diet component. In these studies there were no statistically significant differences in weight loss between interventions. Four RCTs compared multicomponent interventions that focused on the physical activity component. There was little consistency in the pattern of results seen, in part owing to the differences in the interventions. In one RCT the intervention focused on the goal-setting interval and it appeared that weight loss was greatest in those given daily goals compared with weekly goals. Overall, where measured, it appeared that most groups began to regain weight at further follow-up. Of the 419 studies identified in the cost-effectiveness searches, none met the full inclusion criteria. Two economic evaluations are described in our review; however, caution is required in their interpretation, as they did not meet all inclusion criteria. Lifetime chronic disease models were used in these studies and the models included the costs and benefits of avoiding chronic illness. Both studies found the interventions to be cost-effective, with estimates varying between -£473 and £7200 (US$12,640) per quality-adjusted life-year gained; methodological omissions from these studies were apparent and caution is therefore required in the interpretation of these results. CONCLUSIONS Long-term multicomponent weight management interventions were generally shown to promote weight loss in overweight or obese adults. Weight changes were small however and weight regain was common. There were few similarities between the included studies; consequently an overall interpretation of the results was difficult to make. There is some evidence that weight management interventions are likely to be cost-effective, although caution is required as there were some limitations in the two cost-evaluation studies described. FUNDING The National Institute for Health Research Health Technology Assessment programme.
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Affiliation(s)
- E Loveman
- Southampton Health Technology Assessments Centre, UK
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Abstract
A high resistance nanogap platform was used to trap and electrically characterize 30 nm thiolated double-stranded DNA molecules. High resolution scanning electron microscopy was also used to image the trapped DNA strands. It was found that the surface state of the electrodes and underlying substrate could influence the measurements of trapped molecules when the measured resistances were on the order of TΩ or greater. Hydrophilic surfaces gave rise to larger leakage currents that could potentially mask the underlying signals from molecules positioned in the nanogap. Finally, the careful handling of the samples and control of the environment is essential to avoid surface charging of the oxide substrate layer as these parasitic charges affect electrical measurements of the nanogap. The presented results thus outline some important considerations when making low-conductance measurements on molecules and should prove useful for the characterization of molecules in molecular electronics or sensors employing nanogap platforms.
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Affiliation(s)
- K Welch
- Division for Nanotechnology and Functional Materials, Department of Engineering Sciences, Uppsala University, Uppsala, Sweden
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Takeda A, Cooper K, Bird A, Baxter L, Frampton GK, Gospodarevskaya E, Welch K, Bryant J. Recombinant human growth hormone for the treatment of growth disorders in children: a systematic review and economic evaluation. Health Technol Assess 2011; 14:1-209, iii-iv. [PMID: 20849734 DOI: 10.3310/hta14420] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Recombinant human growth hormone (rhGH) is licensed for short stature associated with growth hormone deficiency (GHD), Turner syndrome (TS), Prader-Willi syndrome (PWS), chronic renal insufficiency (CRI), short stature homeobox-containing gene deficiency (SHOX-D) and being born small for gestational age (SGA). OBJECTIVES To assess the clinical effectiveness and cost-effectiveness of rhGH compared with treatment strategies without rhGH for children with GHD, TS, PWS, CRI, SHOX-D and those born SGA. DATA SOURCES The systematic review used a priori methods. Key databases were searched (e.g. MEDLINE, EMBASE, NHS Economic Evaluation Database and eight others) for relevant studies from their inception to June 2009. A decision-analytical model was developed to determine cost-effectiveness in the UK. STUDY SELECTION Two reviewers assessed titles and abstracts of studies identified by the search strategy, obtained the full text of relevant papers, and screened them against inclusion criteria. STUDY APPRAISAL Data from included studies were extracted by one reviewer and checked by a second. Quality of included studies was assessed using standard criteria, applied by one reviewer and checked by a second. Clinical effectiveness studies were synthesised through a narrative review. RESULTS Twenty-eight randomised controlled trials (RCTs) in 34 publications were included in the systematic review. GHD: Children in the rhGH group grew 2.7 cm/year faster than untreated children and had a statistically significantly higher height standard deviation score (HtSDS) after 1 year: -2.3 ± 0.45 versus -2.8 ± 0.45. TS: In one study, treated girls grew 9.3 cm more than untreated girls. In a study of younger children, the difference was 7.6 cm after 2 years. HtSDS values were statistically significantly higher in treated girls. PWS: Infants receiving rhGH for 1 year grew significantly taller (6.2 cm more) than those untreated. Two studies reported a statistically significant difference in HtSDS in favour of rhGH. CRI: rhGH-treated children in a 1-year study grew an average of 3.6 cm more than untreated children. HtSDS was statistically significantly higher in treated children in two studies. SGA: Criteria were amended to include children of 3+ years with no catch-up growth, with no reference to mid-parental height. Only one of the RCTs used the licensed dose; the others used higher doses. Adult height (AH) was approximately 4 cm higher in rhGH-treated patients in the one study to report this outcome, and AH-gain SDS was also statistically significantly higher in this group. Mean HtSDS was higher in treated than untreated patients in four other studies (significant in two). SHOX-D: After 2 years' treatment, children were approximately 6 cm taller than the control group and HtSDS was statistically significantly higher in treated children. The incremental cost per quality adjusted life-year (QALY) estimates of rhGH compared with no treatment were: 23,196 pounds for GHD, 39,460 pounds for TS, 135,311 pounds for PWS, 39,273 pounds for CRI, 33,079 pounds for SGA and 40,531 pounds for SHOX-D. The probability of treatment of each of the conditions being cost-effective at 30,000 pounds was: 95% for GHD, 19% for TS, 1% for PWS, 16% for CRI, 38% for SGA and 15% for SHOX-D. LIMITATIONS Generally poorly reported studies, some of short duration. CONCLUSIONS Statistically significantly larger HtSDS values were reported for rhGH-treated children with GHD, TS, PWS, CRI, SGA and SHOX-D. rhGH-treated children with PWS also showed statistically significant improvements in body composition measures. Only treatment of GHD would be considered cost-effective at a willingness-to-pay threshold of 20,000 to 30,000 pounds per QALY gained. This analysis suggests future research should include studies of longer than 2 years reporting near-final height or final adult height.
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Affiliation(s)
- A Takeda
- Southampton Health Technology Assessments Centre, Southampton, UK
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Jafri SHM, Blom T, Leifer K, Strømme M, Löfås H, Grigoriev A, Ahuja R, Welch K. Assessment of a nanoparticle bridge platform for molecular electronics measurements. Nanotechnology 2010; 21:435204. [PMID: 20890018 DOI: 10.1088/0957-4484/21/43/435204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
A combination of electron beam lithography, photolithography and focused ion beam milling was used to create a nanogap platform, which was bridged by gold nanoparticles in order to make electrical measurements and assess the platform under ambient conditions. Non-functionalized electrodes were tested to determine the intrinsic response of the platform and it was found that creating devices in ambient conditions requires careful cleaning and awareness of the contributions contaminants may make to measurements. The platform was then used to make measurements on octanethiol (OT) and biphenyldithiol (BPDT) molecules by functionalizing the nanoelectrodes with the molecules prior to bridging the nanogap with nanoparticles. Measurements on OT show that it is possible to make measurements on relatively small numbers of molecules, but that a large variation in response can be expected when one of the metal-molecule junctions is physisorbed, which was partially explained by attachment of OT molecules to different sites on the surface of the Au electrode using a density functional theory calculation. On the other hand, when dealing with BPDT, high yields for device creation are very difficult to achieve under ambient conditions. Significant hysteresis in the I-V curves of BPDT was also observed, which was attributed primarily to voltage induced changes at the interface between the molecule and the metal.
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Affiliation(s)
- S H M Jafri
- Division for Electron Microscopy and Nanoengineering, Department of Engineering Sciences, Uppsala University, Uppsala, Sweden
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Welch K. First Do No Harm: Being a Resilient Doctor in the 21st Century. By Leanne Rowe and Michael Kidd. Alcohol Alcohol 2010. [DOI: 10.1093/alcalc/agq019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Loveman E, Jones J, Hartwell D, Bird A, Harris P, Welch K, Clegg A. The clinical effectiveness and cost-effectiveness of topotecan for small cell lung cancer: a systematic review and economic evaluation. Health Technol Assess 2010; 14:1-204. [DOI: 10.3310/hta14190] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
- E Loveman
- Southampton Health Technology Assessments Centre (SHTAC), UK
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