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Iglesias-Mejuto A, Magariños B, Ferreira-Gonçalves T, Starbird-Pérez R, Álvarez-Lorenzo C, Reis CP, Ardao I, García-González CA. Vancomycin-loaded methylcellulose aerogel scaffolds for advanced bone tissue engineering. Carbohydr Polym 2024; 324:121536. [PMID: 37985110 DOI: 10.1016/j.carbpol.2023.121536] [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: 08/01/2023] [Revised: 10/20/2023] [Accepted: 10/27/2023] [Indexed: 11/22/2023]
Abstract
Scaffolds grafting combined with local delivery of antibiotics at the injury site may promote bone regeneration along with prevention of infections. In this work, a processing strategy combining the 3D-printing of polysaccharide-based inks with supercritical (sc)CO2 technology was employed to manufacture drug-loaded, nanostructured, and personalized-to-patient aerogels for the first time. Methylcellulose (MC) was employed as graft matrix endowed with nanohydroxyapatite (nHA) to confer bioactivity as required in bone tissue engineering (BTE). MC-nHA aerogels were obtained through the 3D-printing of hydrogel-based scaffolds followed by scCO2 drying. Aerogels were loaded with vancomycin (VAN), an antibiotic employed in the management of bone infections. Textural properties and printing fidelity of scaffolds were studied as well as VAN release, long-term bioactivity, and pre-osteoblasts mineralization. In vitro cell studies and in vivo Artemia salina tests were carried out to evaluate the potential toxicity of the antibiotic-loaded aerogels. Aerogels efficacy in inhibiting bacterial growth was assessed by antimicrobial tests with Staphylococcus aureus. Textural stability of the aerogels after 7 months of storage was also evaluated. Obtained results showed that the scaffolds promoted the intended two-in-one effect (bone repair and infection management simultaneously) in a personalized way, regulating formulation design, drug dose, and porosity.
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Affiliation(s)
- Ana Iglesias-Mejuto
- AerogelsLab, I+D Farma Group (GI-1645), Department of Pharmacology, Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, iMATUS and Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - Beatriz Magariños
- Departamento de Microbiología y Parasitología, Facultad de Biología, CIBUS, Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - Tânia Ferreira-Gonçalves
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Professor Gama Pinto, 1649-003 Lisboa, Portugal; Instituto de Biofísica e Engenharia Biomédica (IBEB), Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Ricardo Starbird-Pérez
- Centro de Investigación y de Servicios Químicos y Microbiológicos (CEQIATEC), School of Chemistry, Instituto Tecnológico de Costa Rica, 159-7050 Cartago, Costa Rica; Centro de Investigación en Ciencia e Ingeniería de Materiales (CICIMA), Universidad de Costa Rica, 11501-2060 San José, Costa Rica
| | - Carmen Álvarez-Lorenzo
- AerogelsLab, I+D Farma Group (GI-1645), Department of Pharmacology, Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, iMATUS and Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - Catarina Pinto Reis
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Av. Professor Gama Pinto, 1649-003 Lisboa, Portugal; Instituto de Biofísica e Engenharia Biomédica (IBEB), Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Inés Ardao
- BioFarma Research group, Department of Pharmacology, Pharmacy and Pharmaceutical Technology, Innopharma Drug Screening and Pharmacogenomics Platform, Centro Singular de Investigación en Medicina Molecular y Enfermedades Crónicas (CiMUS), Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
| | - Carlos A García-González
- AerogelsLab, I+D Farma Group (GI-1645), Department of Pharmacology, Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, iMATUS and Health Research Institute of Santiago de Compostela (IDIS), Universidade de Santiago de Compostela, E-15782 Santiago de Compostela, Spain.
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Coban SN, Polatoglu I, Eroglu E. Methyl cellulose/okra mucilage composite films, functionalized with Hypericum perforatum oil and gentamicin, as a potential wound dressing. Int J Biol Macromol 2024; 254:127757. [PMID: 38287573 DOI: 10.1016/j.ijbiomac.2023.127757] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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: 05/02/2023] [Revised: 10/19/2023] [Accepted: 10/27/2023] [Indexed: 01/31/2024]
Abstract
There is a growing demand for the development of functional wound dressings enriched with bioactive natural compounds to improve the quality of life of the population by accelerating the healing process of chronic wounds. In this regard, a functional composite film of okra mucilage (OM) and methylcellulose (MC) incorporated with Hypericum perforatum oil (Hp) and gentamicin (G) was prepared and characterized as a wound dressing. Increasing Hp resulted in improved film properties with a more porous structure, higher WVTR, and lower surface hydrophobicity. Furthermore, incorporating Hp into OM:MC films led to increased elongation at the break while reducing the tensile strength of the films. The highest values of total antioxidant capacity (1.09-1.16 mM trolox equivalent) and total phenolic content (13.76-16.94 μg GA equivalent mL-1) were measured in the composite films containing the highest Hp concentration (1.5 %). In addition, OM:MC/HpG composite films exhibited significant antibacterial activity against both E. coli and S. aureus and prevented the transmission of these bacteria through the films. Hp incorporation reduced the cytotoxic effects of OM:MC films on BJ cells and increased the wound closure rate in vitro. In conclusion, the developed OM:MC/HpG composite film can be a promising candidate as a novel wound dressing with its superior properties.
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Affiliation(s)
- Seyda Nur Coban
- Manisa Celal Bayar University, Faculty of Engineering, Department of Bioengineering, 45140 Manisa, Turkey
| | - Ilker Polatoglu
- Manisa Celal Bayar University, Faculty of Engineering, Department of Bioengineering, 45140 Manisa, Turkey
| | - Erdal Eroglu
- Manisa Celal Bayar University, Faculty of Engineering, Department of Bioengineering, 45140 Manisa, Turkey.
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Jergitsch M, Alluè-Mengual Z, Perez RA, Mateos-Timoneda MA. A systematic approach to improve printability and cell viability of methylcellulose-based bioinks. Int J Biol Macromol 2023; 253:127461. [PMID: 37852401 DOI: 10.1016/j.ijbiomac.2023.127461] [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: 09/08/2023] [Revised: 10/11/2023] [Accepted: 10/14/2023] [Indexed: 10/20/2023]
Abstract
Printability in 3D extrusion bioprinting encompasses extrudability, filament formation, and shape fidelity. Rheological properties can predict the shape fidelity of printed hydrogels. In particular, tan(δ), the ratio between loss (G'') and storage (G') modulus (G''/G'), is a powerful indicator of printability. This study explores the effect of different salt, sucrose, and MC concentrations on tan(δ), and therefore the printability of methylcellulose (MC) hydrogels. Salt and sucrose increased G', lowering tan(δ) and enabling printing of scaffolds with high shape fidelity. Conversely, MC concentration increased G'' and G', having a lesser effect on tan(δ). Shape fidelity of three formulations with similar G' but varying tan(δ) values were compared. Higher tan(δ) led to reduced height, while lower tan(δ) improved shape fidelity. Cell viability increased when reducing MC content, extrusion rate, and nozzle gauge. Higher MC concentration (G' > 1.5 kPa) increased the influence of needle size and extrusion rate on cell viability. Hydrogels with G' < 1 kPa could be extruded at high rates with small nozzles, minimally affecting cell viability. This work shows a direct relationship between tan(δ) and printability of MC-based hydrogels. Lowering the complex modulus of hydrogels, mitigates extrusion stress, thus improving cell survival.
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Affiliation(s)
- Maximilian Jergitsch
- Bioengineering Institute of Technology, Universitat Internacional de Catalunya, Josep Trueta, 08195 Sant Cugat del Vallès, Barcelona, Spain; Department of Basic Sciences, Faculty of Medicine and Health Science, Universitat Internacional de Catalunya, JosepTrueta, 08195 Sant Cugat del Vallès, Barcelona, Spain
| | - Zoe Alluè-Mengual
- Bioengineering Institute of Technology, Universitat Internacional de Catalunya, Josep Trueta, 08195 Sant Cugat del Vallès, Barcelona, Spain; Department of Basic Sciences, Faculty of Medicine and Health Science, Universitat Internacional de Catalunya, JosepTrueta, 08195 Sant Cugat del Vallès, Barcelona, Spain
| | - Roman A Perez
- Bioengineering Institute of Technology, Universitat Internacional de Catalunya, Josep Trueta, 08195 Sant Cugat del Vallès, Barcelona, Spain; Department of Basic Sciences, Faculty of Medicine and Health Science, Universitat Internacional de Catalunya, JosepTrueta, 08195 Sant Cugat del Vallès, Barcelona, Spain
| | - Miguel A Mateos-Timoneda
- Bioengineering Institute of Technology, Universitat Internacional de Catalunya, Josep Trueta, 08195 Sant Cugat del Vallès, Barcelona, Spain; Department of Basic Sciences, Faculty of Medicine and Health Science, Universitat Internacional de Catalunya, JosepTrueta, 08195 Sant Cugat del Vallès, Barcelona, Spain.
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Gokarn A, Tembhare PR, Syed H, Sanyal I, Kumar R, Parab S, Khanka T, Punatar S, Kedia S, Ghogale SG, Deshpande N, Nikam Y, Girase K, Mirgh S, Jindal N, Bagal B, Chichra A, Nayak L, Bonda A, Rath S, Hiregoudar S, Poojary M, Saha S, Ojha S, Subramanian PG, Khattry N. Long-Term Cryopreservation of Peripheral Blood Stem Cell Harvest Using Low Concentration (4.35%) Dimethyl Sulfoxide with Methyl Cellulose and Uncontrolled Rate Freezing at -80 °C: An Effective Option in Resource-Limited Settings. Transplant Cell Ther 2023; 29:777.e1-777.e8. [PMID: 37678607 DOI: 10.1016/j.jtct.2023.08.032] [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: 07/02/2023] [Revised: 08/30/2023] [Accepted: 08/31/2023] [Indexed: 09/09/2023]
Abstract
Long-term cryopreservation of peripheral blood stem cells (PBSCs) is highly useful in the setting of tandem/multiple transplantations or treatment of relapse in the autologous hematopoietic stem cell transplantation (HSCT) setting. Even in allogeneic HSCT, donor lymphocyte infusions may be stored for months to years if excess stem cells are collected from donors. Cryopreservation is a delicate, complex, and costly procedure, and higher concentrations of dimethyl sulfoxide (DMSO), a commonly used cryoprotectant, can be toxic to cells and cause adverse effects in the recipient during infusions. In this study, we examined the effect of long-term cryopreservation using 4.35% DMSO (as final concentration) with methyl cellulose and uncontrolled rate freezing in a mechanical freezer (-80 °C) on the viability and colony-forming ability of CD34+ human PBSCs. For patients undergoing autologous HSCT, PBSCs were cryopreserved using DMSO (final concentration of 4.35%) with methyl cellulose. The post-thaw viability of PBSCs was determined using Trypan blue exclusion and flow cytometry-based 7-amino-actinomycin-D (FC-7AAD) methods. Concentrations of CD34+ stem cells and immune cell subsets in post-thaw PBSC harvest samples were assessed using multicolor flow cytometry, and the clonogenic potential of post-thaw stem cells was studied using a colony-forming unit (CFU) assay. CD34+ stem cell levels were correlated with the prestorage CD34 levels using the Pearson correlation test. The viability results in the Trypan blue dye exclusion method and the flow cytometry-based method were compared using Bland-Altman plots. We studied 26 PBSC harvest samples with a median cryopreservation duration of 6.6 years (range, 3.8 to 11.5 years). The median viability of post-thaw PBSCs was >80% using both methods, with a weak agreement between them (r = .03; P = .5). The median CD34+ stem cell count in the post-thaw samples was 9.13 × 106/kg (range, .44 to 26.27 × 106/kg). The CFU assay yielded a good proliferation and differentiation potential in post-thaw PBSCs, with a weak correlation between granulocyte macrophage CFU and CD34+ stem cell levels (r = .4; P = .05). Two samples that had been cryopreserved for >8 years showed low viability. Cryopreservation of PBSCs using 4.35% DMSO with methyl cellulose and uncontrolled freezing in a mechanical freezer at -80 °C allows the maintenance of long-term viability of PBSC for up to 8 years.
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Affiliation(s)
- Anant Gokarn
- Department of Medical Oncology, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India; Homi Bhabha National Institute, Mumbai, India
| | - Prashant R Tembhare
- Homi Bhabha National Institute, Mumbai, India; Hematopathology Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Hasan Syed
- Homi Bhabha National Institute, Mumbai, India; Hasan Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Isha Sanyal
- Hematopathology Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Rohit Kumar
- Hasan Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Sarika Parab
- Department of Transfusion Medicine, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Twinkle Khanka
- Hematopathology Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Sachin Punatar
- Department of Medical Oncology, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India; Homi Bhabha National Institute, Mumbai, India
| | - Shweta Kedia
- Hematopathology Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Sitaram G Ghogale
- Hematopathology Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Nilesh Deshpande
- Hematopathology Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Yuvraj Nikam
- Hasan Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Karishma Girase
- Hematopathology Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Sumeet Mirgh
- Department of Medical Oncology, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India; Homi Bhabha National Institute, Mumbai, India
| | - Nishant Jindal
- Department of Medical Oncology, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India; Homi Bhabha National Institute, Mumbai, India
| | - Bhausaheb Bagal
- Department of Medical Oncology, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India; Homi Bhabha National Institute, Mumbai, India
| | - Akanksha Chichra
- Department of Medical Oncology, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India; Homi Bhabha National Institute, Mumbai, India
| | - Lingaraj Nayak
- Department of Medical Oncology, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India; Homi Bhabha National Institute, Mumbai, India
| | - Avinash Bonda
- Department of Medical Oncology, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India; Homi Bhabha National Institute, Mumbai, India
| | - Sushmita Rath
- Department of Medical Oncology, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India; Homi Bhabha National Institute, Mumbai, India
| | - Sumathi Hiregoudar
- Homi Bhabha National Institute, Mumbai, India; Department of Transfusion Medicine, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Minal Poojary
- Homi Bhabha National Institute, Mumbai, India; Department of Transfusion Medicine, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Suryatapa Saha
- Homi Bhabha National Institute, Mumbai, India; Department of Transfusion Medicine, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Shashank Ojha
- Homi Bhabha National Institute, Mumbai, India; Department of Transfusion Medicine, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Papagudi G Subramanian
- Homi Bhabha National Institute, Mumbai, India; Hematopathology Laboratory, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India
| | - Navin Khattry
- Department of Medical Oncology, Advanced Centre for Treatment, Research, and Education in Cancer, Tata Memorial Center, Navi Mumbai, India; Homi Bhabha National Institute, Mumbai, India
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Jones NM, Nathanson AD, Chell S, DeAngelis E, Whelan G, Willé D, Cheng K. The prolyl hydroxylase inhibitor GSK1120360A reduces early brain injury, but protection is not maintained in a neonatal rat model of hypoxic ischaemic encephalopathy. Int J Dev Neurosci 2022; 82:423-435. [PMID: 35662244 DOI: 10.1002/jdn.10199] [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] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 05/10/2022] [Accepted: 05/31/2022] [Indexed: 11/06/2022] Open
Abstract
Hypoxic-ischemic encephalopathy (HIE) in newborns is associated with high morbidity and mortality, with many babies suffering long-term neurological deficits. Currently, treatment options are limited to therapeutic hypothermia, which is not appropriate for use in all babies. Previous studies have shown protective effects of increasing the transcription factor-hypoxia-inducible factor-1 (HIF-1) in animal models, by using mild hypoxia or compounds that act as prolyl hydroxylase inhibitors (PHIs). Here, we aimed to examine the neuroprotective actions of an orally active, small molecule PHI, GSK1120360A in a neonatal rat model of hypoxia-ischemia (HI) compared to another PHI, desferrioxamine (DFX). Sprague-Dawley rats underwent HI surgery on postnatal day 7 (P7), where unilateral carotid artery occlusion was performed followed by hypoxia (8% oxygen, 3 h). Initial testing showed that GSK1120360A and erythropoietin levels were detectable in plasma at 6 h following oral exposure to GSK1120360A. For the short-term neuroprotection study, pups were assigned to receive either saline (s.c), desferrioxamine (DFX-200 mg/kg, s.c), methylcellulose (1%, oral) or GSK1120360A (30 mg/kg, oral) immediately after HI. Histological analysis showed that GSK1120360A in this setting reduced brain injury size 7 days after HI, compared to the methylcellulose vehicle control group. DFX had no significant effect on injury size compared to saline group at the same 7 day timepoint. In the long-term neuroprotection study, pups were randomly assigned to be administered methylcellulose (1%, oral) or GSK1120360A (30 mg/kg, oral) immediately after HI. On P42, rats underwent behavioural testing using the forelimb grip strength, grid walking and novel object recognition tasks, and brains were collected for histological analysis. Long-term behavioural deficits were observed in grid walking, grip strength and novel object recognition tests after HI which were not improved in the GSK1120360A treatment group compared to the methylcellulose group. Similarly, there was no improvement in injury size on P42 in the GSK1120360A study group compared to the methylcellulose group. Here, we have shown that GSK1120360A can reduce brain injury at 7 days but that this neuroprotective benefit is not maintained when examined at 5 weeks after HI.
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Affiliation(s)
- Nicole M Jones
- Department of Pharmacology, School of Medical Sciences, University of New South Wales Sydney, Sydney, New South Wales, Australia
| | - Anton D Nathanson
- Department of Pharmacology, School of Medical Sciences, University of New South Wales Sydney, Sydney, New South Wales, Australia
| | - Simon Chell
- Medicines Research Centre, GlaxoSmithKline, Stevenage, UK
| | | | - Greg Whelan
- Medicines Research Centre, GlaxoSmithKline, Stevenage, UK
| | - David Willé
- Medicines Research Centre, GlaxoSmithKline, Stevenage, UK
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Thacker M, Chen YN, Lin CP, Lin FH. Nitrogen-Doped Titanium Dioxide Mixed with Calcium Peroxide and Methylcellulose for Dental Bleaching under Visible Light Activation. Int J Mol Sci 2021; 22:ijms22073759. [PMID: 33916642 PMCID: PMC8038621 DOI: 10.3390/ijms22073759] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 03/30/2021] [Accepted: 03/31/2021] [Indexed: 11/16/2022] Open
Abstract
The available tooth whitening products in the market contain high concentrations of hydrogen peroxide (H2O2) as an active ingredient. Therefore, in order to curb the high H2O2 concentration and instability of liquid H2O2, this study evaluated the efficacy and cytotoxicity of the bleaching gel composed of 10% calcium peroxide (CaO2) and visible-light-activating nitrogen-doped titanium dioxide (N-TiO2) with methyl cellulose as a thickener. Extracted bovine teeth were discolored using coffee and black tea stain solution and were divided into two groups (n = 6). Bleaching was performed thrice on each tooth specimen in both the groups, with one minute of visible light irradiation during each bleaching time. The CIELAB L*a*b* values were measured pre- and post-bleaching. The N-TiO2 calcinated at 350 °C demonstrated a shift towards the visible light region by narrowing the band gap energy from 3.23 eV to 2.85 eV. The brightness (ΔL) and color difference (ΔE) increased as bleaching progressed each time in both the groups. ANOVA results showed that the number of bleaching significantly affected ΔE (p < 0.05). The formulated bleaching gel exhibits good biocompatibility and non-toxicity upon exposure to 3T3 cells. Our findings showed that CaO2-based bleaching gel at neutral pH could be a stable, safe, and effective substitute for tooth whitening products currently available in the market.
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Affiliation(s)
- Minal Thacker
- Graduate Institute of Biomedical Engineering, National Taiwan University, Taipei 10051, Taiwan; (M.T.); (Y.-N.C.)
| | - Yi-Ning Chen
- Graduate Institute of Biomedical Engineering, National Taiwan University, Taipei 10051, Taiwan; (M.T.); (Y.-N.C.)
| | - Chun-Pin Lin
- Graduate Institute of Clinical Dentistry, School of Dentistry, National Taiwan University, Taipei 10617, Taiwan;
- National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei 10617, Taiwan
| | - Feng-Huei Lin
- Graduate Institute of Biomedical Engineering, National Taiwan University, Taipei 10051, Taiwan; (M.T.); (Y.-N.C.)
- Institute of Biomedical Engineering and Nanomedicine, National Health Research Institutes, Miaoli County 35053, Taiwan
- Correspondence: ; Tel.: +886-928-260-400
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Rastin H, Ramezanpour M, Hassan K, Mazinani A, Tung TT, Vreugde S, Losic D. 3D bioprinting of a cell-laden antibacterial polysaccharide hydrogel composite. Carbohydr Polym 2021; 264:117989. [PMID: 33910727 DOI: 10.1016/j.carbpol.2021.117989] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 03/22/2021] [Accepted: 03/23/2021] [Indexed: 12/17/2022]
Abstract
Bioink with inherent antibacterial activity is of particular interest for tissue engineering application due to the growing number of bacterial infections associated with impaired wound healing or bone implants. However, the development of cell-laden bioink with potent antibacterial activity while supporting tissue regeneration proved to be challenging. Here, we introduced a cell-laden antibacterial bioink based on Methylcellulose/Alginate (MC/Alg) hydrogel for skin tissue engineering via elimination of the risks associated with a bacterial infection. The key feature of the bioink is the use of gallium (Ga+3) in the design of bioink formulation with dual functions. First, Ga+3 stabilized the hydrogel bioink by the formation of ionic crosslinking with Alg chains. Second, the gallium-crosslinked bioink exhibited potent antibacterial activity toward both Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa) bacteria with a bactericidal rate of 99.99 %. In addition, it was found that the developed bioink supported encapsulated fibroblast cellular functions.
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Affiliation(s)
- Hadi Rastin
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, South Australia, 5005, Australia; ARC Research Hub for Graphene Enabled Industry Transformation, The University of Adelaide, South Australia, 5005, Australia
| | - Mahnaz Ramezanpour
- Department of Surgery-Otolaryngology Head and Neck Surgery, The University of Adelaide, Woodville South, Australia
| | - Kamrul Hassan
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, South Australia, 5005, Australia; ARC Research Hub for Graphene Enabled Industry Transformation, The University of Adelaide, South Australia, 5005, Australia
| | - Arash Mazinani
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, South Australia, 5005, Australia; ARC Research Hub for Graphene Enabled Industry Transformation, The University of Adelaide, South Australia, 5005, Australia
| | - Tran Thanh Tung
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, South Australia, 5005, Australia; ARC Research Hub for Graphene Enabled Industry Transformation, The University of Adelaide, South Australia, 5005, Australia
| | - Sarah Vreugde
- Department of Surgery-Otolaryngology Head and Neck Surgery, The University of Adelaide, Woodville South, Australia
| | - Dusan Losic
- School of Chemical Engineering and Advanced Materials, The University of Adelaide, South Australia, 5005, Australia; ARC Research Hub for Graphene Enabled Industry Transformation, The University of Adelaide, South Australia, 5005, Australia.
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Correa-Matos NJ, Donovan SM, Tappenden KA. Fermentable Fibers Enhance Aspects of Innate and Adaptive Immunity in Piglets infected with Salmonella Typhimurium. P R Health Sci J 2020; 39:311-318. [PMID: 33320460] [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] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
OBJECTIVE To test the hypothesis that fermentable fiber prevents Salmonella typhimurium infection-associated symptoms by enhancing innate and adaptive immune system in neonatal pigs. METHODS Two-d-old piglets (n=120) were randomized to receive either a nutritionally complete sow milk replacer formula (CON), or supplemented with methylcellulose (MCEL-non-fermentable), soy polysaccharides (SPS-moderately fermentable), or fructooligosaccharides (FOS-highly fermentable). On d7, piglets received an oral gavage of S. typhimurium-798, and continued receiving the same diets up to 48h post-infection. Ileal mucosal samples were obtained for further analyses. RESULTS A reduction in chloride secretion was observed in FOS when compared to other diets (p<0.0003). The number of ileal sulfo-acidomucins was higher (p<0.05) in FOS before infection compared with other diets. NFkB was inhibited in FOS following infection (p<0.05), when compared with CON. IL-1β expression was increased at 4h post-infection (p<0.05) in CON; however, this response was attenuated in the fiber groups. IL-6 expression was higher (p<0.05) in CON post- infection, higher in SPS at 24h (p<0.05), but unchanged in MCEL and FOS when compared to pre-infection values. FOS had a higher expression of neutrophil-chemoattractant IL-8 before infection (p<0.05) compared to other groups. CONCLUSION The reduction in chloride secretion, proinflammatory cytokines expression and NFkB activation, and increased number of sulfo-acidomucins, and IL-8 expression in the fiber groups, indicates that the degree of fermentability impacts the innate and adaptive immune system, and could be the mechanisms by which dietary fibers reduce S. typhimurium infection-associated-symptoms in neonatal pigs and apply these results to infants.
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Affiliation(s)
- Nancy J Correa-Matos
- Associate Professor, Nutrition and Dietetics Program, College of Natural Sciences, University of Puerto Rico, Rio Piedras Campus, Rio Piedras, Puerto Rico
| | - Sharon M Donovan
- Professor, Department of Food Science and Human Nutrition, Carl R. Woese Institute for Genomic Biology, University of Illinois, USA
| | - Kelly A Tappenden
- Professor, Department Head, Kinesiology and Nutrition, University of Illinois at Chicago, IL, USA
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9
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Abstract
The rapid development of clinical diagnostic imaging technology, in tandem with medical and angiogenesis research, has led to some major advances in healthcare. The chorioallantoic membrane assay is commonly used for studying normal angiogenesis as well as putative angiogenic and antiangiogenic substances. Despite the progress, it is generally recognized that a major problem is the lack of a suitable quantitative bioassay for angiogenesis. Image probing is a novel solution to this problem, which, together with its associated discipline of evaluating angiogenesis, is showing great potential not only for accurate measurement of even very small blood vessels but also for detailed three-dimensional quantification of blood vessels and surface characterization. This technique could be a helpful tool for quantification in angiogenesis research.
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Affiliation(s)
- Sohail Ejaz
- Biosafety Research Institute, Chonbuk National University, Jeonju, South Korea
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Kareem N, Yates E, Skidmore M, Hoole D. In vitro investigations on the effects of semi-synthetic, sulphated carbohydrates on the immune status of cultured common carp (Cyprinus carpio) leucocytes. Fish Shellfish Immunol 2018; 74:213-222. [PMID: 29289653 DOI: 10.1016/j.fsi.2017.12.047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 12/15/2017] [Accepted: 12/22/2017] [Indexed: 06/07/2023]
Abstract
The rapid emergence of drug resistance, unfavourable immunosuppression and mounting evidence to suggest the deleterious accumulation of drug breakdown residues within animal tissues has driven a strong desire to move away from these current methods of disease control. Some natural products such as β-glucan, which are extracted from, for example, plants and fungi, are able to modulate the immune system and increase protection against diseases. However, these products are heterogeneous and their effects can be variable thus limiting their applicability and reliability. Carbohydrates were modified via chemical sulphation and these semi-synthetic, sulphated carbohydrates analysed for their immunological activity utilising carp pronephric cells and a carp leucocyte cell line (CLC). A sulphated β(1,4)-glucan, methyl hydroxyethyl cellulose sulphate (MHCS), demonstrated a stimulatory effect on fish immune cells. MHCS induced a range of bioactive effects in carp leucocyte cells whilst not affecting cell viability when cells were exposed for 24 h at concentrations of 1-150 μgml-1. MHCS stimulated the innate immune system where a significant increase in respiratory burst activity was observed at concentrations 25-250 μgml-1 in comparison to control (sterile water), cellulose ether, MacroGard® and zymosan. Also, under in mock bacterial and viral infection conditions i.e. Lipopolysaccharide (LPS) and polyinosinic:polycytidylic acid (Poly(I:C)), MHCS enhanced the immune responses of pronephric cells by stimulating the respiratory burst activity at concentrations 50 and 150 μgml-1. MHCS also enhanced the expression of cytokines including interleukin 1 beta (IL1β), tumor necrosis factor alpha 1 and 2 (TNFα 1,2), interferons alpha 2 (IFN α2) and inducible nitric oxide synthase (iNOS) in carp pronephric cells. It is proposed that this new semi-synthetic carbohydrate is a potential candidate for the development of a new generation of immunostimulants and adjuvants for use in vaccination strategies in aquaculture.
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Affiliation(s)
- N Kareem
- School of Life Sciences, Keele University, Keele, Staffordshire, ST5 5BG, UK; Faculty of Agricultural Sciences, University of Sulaimani, Kurdistan Region, Iraq
| | - E Yates
- Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - M Skidmore
- School of Life Sciences, Keele University, Keele, Staffordshire, ST5 5BG, UK; Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - D Hoole
- School of Life Sciences, Keele University, Keele, Staffordshire, ST5 5BG, UK.
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Ray-Chaudhuri N, Voros GM, Sutherland S, Figueiredo FC. Comparison of the Effect of Sodium Hyaluronate (Ophthalin®) and Hydroxypropylmethylcellulose (HPMC-Ophtal®) on Corneal Endothelium, Central Corneal Thickness, and Intraocular Pressure after Phacoemulsification. Eur J Ophthalmol 2018; 16:239-46. [PMID: 16703541 DOI: 10.1177/112067210601600208] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE To prospectively evaluate the effects of 2% hydroxypropyl-methylcellulose (HPMC-Ophtal) and sodium hyaluronate 1% (Ophthalin) on intraocular pressure, corneal thickness, and endothelial cell loss in small incision cataract surgery with implant. METHODS A total of 110 patients undergoing routine phacoemulsification with implant received either 2% hydroxypropyl methylcellulose or sodium hyaluronate 1% as ophthalmic viscosurgical device. Pre- and postoperative slitlamp examination, intraocular pressure measurement (preoperatively and at 1-4 hours, 1 day, and 7 days postoperatively), ultrasonic pachymetry (preoperatively and at 1 week, 4-6 weeks, and 12 weeks post operatively), and corneal endothelial cell count (preoperatively and 12 weeks postoperatively) were performed. Data were analyzed using two-way analysis of variance. RESULTS All measurements were comparable between the two groups preoperatively. Intraocular pressure was significantly lower in the Ophthalin group at 1 day post operatively, while no significant difference was found between the two groups on the 1-4 hours and 7 days examination. The central corneal thickness was not significantly different between the two groups at any postoperative visit . However, the mean cell density demonstrated a significant fall of 11.76% for Ophthalin and 4.27% for HPMC-Ophtal at 12 weeks post-operatively, the difference between the two being significant (p=0.009). CONCLUSIONS 2% Hydroxypropyl methylcellulose, compared with sodium hyaluronate 1%, is superior in protecting the corneal endothelial cells, has the same effect on central corneal thickness, and is associated with slightly higher intraocular pressure 1 day post operatively. It compares favorably with sodium hyaluronate 1% and can be used as an effective and cheaper alternative in routine small incision cataract surgery with implant.
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Affiliation(s)
- N Ray-Chaudhuri
- Department of Ophthalmology, Royal Victoria Infirmary, University of Newcastle upon Tyne, Newcastle upon Tyne, United Kingdom
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12
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Abstract
The development of simple but effective storage protocols for adult stem cells will greatly enhance their use and utility in tissue-engineering applications. Cryopreservation has shown to be most promising but is a fairly complex process, necessitating the use of chemicals called cryoprotective agents (CPAs), freezing equipment, and obviously, storage in liquid nitrogen. The purpose of this chapter is to present a general overview of cryopreservation storage techniques and the optimal protocols/results obtained in our laboratory for long-term storage of adult stem cells using freezing storage.
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Affiliation(s)
- Shahensha Shaik
- Bioengineering Laboratory, Department of Mechanical Engineering, Louisiana State University, Baton Rouge, LA, USA.
| | - Ram Devireddy
- Bioengineering Laboratory, Department of Mechanical Engineering, Louisiana State University, Baton Rouge, LA, USA
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Schmidt SA, Baumann JA, Stanescu-Siegmund N, Froehlich E, Brambs HJ, Juchems MS. Oral distension methods for small bowel MRI: comparison of different agents to optimize bowel distension. Acta Radiol 2016; 57:1460-1467. [PMID: 26868172 DOI: 10.1177/0284185116631183] [Citation(s) in RCA: 8] [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] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Background Different methods for bowel distension prior to magnetic resonance imaging (MRI) examinations were described in recent years. Purpose To compare orally administered psyllium or locust bean gum / mannitol (LBM) with tylose administered through a duodenal catheter for bowel distension in patients undergoing MRI examination of the small bowel. Material and Methods Three different methods of bowel distension prior to MRI were compared: tylose applied through a duodenal catheter and orally administered psyllium and LBM in three groups with 15 patients each. Datasets were blinded and reviewed independently by two experienced radiologists, who assessed the diagnostic value and the maximum luminal diameter. Results Tylose was superior to psyllium and LBM in the examination of the duodenum and proximal jejunum. LBM was superior to the other methods for distension of the ileum and terminal ileum. The greatest luminal diameter of the duodenum was achieved after tylose and distension of the terminal ileum was the best in patients receiving LBM. The psyllium group was inferior to the other two groups in all segments. Conclusion By using LBM as an oral method of bowel distension, many patients can avoid the unpleasant placement of a duodenal catheter without compromising the diagnostic value of the examination.
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Affiliation(s)
- Stefan A Schmidt
- 1 Department of Diagnostic and Interventional Radiology, University Hospital of Ulm, Ulm, Germany
| | - Julia A Baumann
- 1 Department of Diagnostic and Interventional Radiology, University Hospital of Ulm, Ulm, Germany
| | - Nora Stanescu-Siegmund
- 1 Department of Diagnostic and Interventional Radiology, University Hospital of Ulm, Ulm, Germany
| | - Eckhart Froehlich
- 2 Department of Internal Medicine, Karl-Olga Hospital, Stuttgart, Germany
| | - Hans-Juergen Brambs
- 1 Department of Diagnostic and Interventional Radiology, University Hospital of Ulm, Ulm, Germany
| | - Markus S Juchems
- 3 Department of Diagnostic and Interventional Radiology, Konstanz Hospital, Konstanz, Germany
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Dewan M, Bhowmick B, Sarkar G, Rana D, Bain MK, Bhowmik M, Chattopadhyay D. Effect of methyl cellulose on gelation behavior and drug release from poloxamer based ophthalmic formulations. Int J Biol Macromol 2014; 72:706-10. [PMID: 25256549 DOI: 10.1016/j.ijbiomac.2014.09.021] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [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: 07/16/2014] [Revised: 08/27/2014] [Accepted: 09/09/2014] [Indexed: 11/18/2022]
Abstract
The effect of weight average molecular weight (Mw) of methyl cellulose (MC) on the gelation behavior of Poloxamer 407 (PM) and in vitro release of Ketorolac Tromethamine (KT) from different ophthalmic formulations based on PM is examined. A drop of gelation temperature of PM is observed using MC of various M(w) by test tube tilting method, UV-vis spectroscopy, viscometry and rheometry. It is also observed that the viscosity and gel strength of all the formulations are increased with the increase in Mw of MC. PM with highest Mw of MC provides best drug release property among all the formulations. It is evident from this investigation that there is a distinct effect of M(w) of MC on the gelation behavior of PM as well as on the drug release profile of KT from PM-MC based ophthalmic formulations.
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Affiliation(s)
- Mitali Dewan
- Department of Polymer Science and Technology, University College of Science and Technology, University of Calcutta, 92 A.P.C. Road, Kolkata 700 009, India
| | - Biplab Bhowmick
- Department of Polymer Science and Technology, University College of Science and Technology, University of Calcutta, 92 A.P.C. Road, Kolkata 700 009, India
| | - Gunjan Sarkar
- Department of Polymer Science and Technology, University College of Science and Technology, University of Calcutta, 92 A.P.C. Road, Kolkata 700 009, India
| | - Dipak Rana
- Department of Chemical and Biological Engineering, Industrial Membrane Research Institute, University of Ottawa, 161 Louis Pasteur St., Ottawa, ON K1N 6N5, Canada
| | - Mrinal Kanti Bain
- Contai Polytechnic, Directorate of Technical Education & Training, Contai, East Midnapur, West Bengal-721401, India
| | - Manas Bhowmik
- Himalayan Pharmacy Institute, Sikkim University, Majhitar, Rangpo, East Sikkim-737136, India
| | - Dipankar Chattopadhyay
- Department of Polymer Science and Technology, University College of Science and Technology, University of Calcutta, 92 A.P.C. Road, Kolkata 700 009, India.
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Karaca H, Pérez-Gago MB, Taberner V, Palou L. Evaluating food additives as antifungal agents against Monilinia fructicola in vitro and in hydroxypropyl methylcellulose-lipid composite edible coatings for plums. Int J Food Microbiol 2014; 179:72-9. [PMID: 24742996 DOI: 10.1016/j.ijfoodmicro.2014.03.027] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [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: 12/16/2013] [Revised: 03/14/2014] [Accepted: 03/24/2014] [Indexed: 11/17/2022]
Abstract
Common food preservative agents were evaluated in in vitro tests for their antifungal activity against Monilinia fructicola, the most economically important pathogen causing postharvest disease of stone fruits. Radial mycelial growth was measured in Petri dishes of PDA amended with three different concentrations of the agents (0.01-0.2%, v/v) after 7 days of incubation at 25 °C. Thirteen out of fifteen agents tested completely inhibited the radial growth of the fungus at various concentrations. Among them, ammonium carbonate, ammonium bicarbonate and sodium bicarbonate were the most effective while sodium acetate and sodium formate were the least effective. The effective agents and concentrations were tested as ingredients of hydroxypropyl methylcellulose (HPMC)-lipid edible coatings against brown rot disease on plums previously inoculated with M. fructicola (curative activity). 'Friar' and 'Larry Ann' plums were inoculated with the pathogen, coated with stable edible coatings about 24h later, and incubated at 20 °C and 90% RH. Disease incidence (%) and severity (lesion diameter) were determined after 4, 6, and 8 days of incubation and the 'area under the disease progress stairs' (AUDPS) was calculated. Coatings containing bicarbonates and parabens significantly reduced brown rot incidence in plums, but potassium sorbate, used at 1.0% in the coating formulation, was the most effective agent with a reduction rate of 28.6%. All the tested coatings reduced disease severity to some extent, but coatings containing 0.1% sodium methylparaben or sodium ethylparaben or 0.2% ammonium carbonate or ammonium bicarbonate were superior to the rest, with reduction rates of 45-50%. Overall, the results showed that most of the agents tested in this study had significant antimicrobial activity against M. fructicola and the application of selected antifungal edible coatings is a promising alternative for the control of postharvest brown rot in plums.
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Affiliation(s)
- Hakan Karaca
- Department of Food Engineering, Faculty of Engineering, Pamukkale University, 20070 Camlik, Denizli, Turkey
| | - María B Pérez-Gago
- Postharvest Technology Center (CTP), Valencian Institute for Agricultural Research (IVIA), Apartat Oficial, 46113 Montcada, Valencia, Spain
| | - Verònica Taberner
- Postharvest Technology Center (CTP), Valencian Institute for Agricultural Research (IVIA), Apartat Oficial, 46113 Montcada, Valencia, Spain
| | - Lluís Palou
- Postharvest Technology Center (CTP), Valencian Institute for Agricultural Research (IVIA), Apartat Oficial, 46113 Montcada, Valencia, Spain.
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Sink KS, Chung A, Ressler KJ, Davis M, Walker DL. Anxiogenic effects of CGRP within the BNST may be mediated by CRF acting at BNST CRFR1 receptors. Behav Brain Res 2013; 243:286-93. [PMID: 23376701 DOI: 10.1016/j.bbr.2013.01.024] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 01/16/2013] [Accepted: 01/23/2013] [Indexed: 12/17/2022]
Abstract
Calcitonin gene-related peptide (CGRP) acting within the bed nucleus of the stria terminalis (BNST) increases anxiety as well as neural activation in anxiety-related structures, and mediates behavioral stress responses. Similar effects have been described following intra-ventricular as well as intra-BNST infusions of the stress-responsive neuropeptide, corticotropin releasing factor (CRF). Interestingly, CGRP-positive terminals within the lateral division of the BNST form perisomatic baskets around neurons that express CRF, suggesting that BNST CGRP could exert its anxiogenic effects by increasing release of CRF from these neurons. With this in mind, the present set of experiments was designed to examine the role of CRFR1 signaling in the anxiogenic effects of CGRP within the BNST and to determine whether CRF from BNST neurons contributes to these effects. Consistent with previous studies, we found that 400 ng CGRP infused bilaterally into the BNST increased the acoustic startle response and induced anxiety-like behavior in the elevated plus maze compared to vehicle. Both of these effects were attenuated by 10mg/kg PO of the CRFR1 antagonist, GSK876008. GSK876008 alone did not affect startle. An intra-BNST infusion of the CRFR1 antagonist CP376395 (2 μg) also blocked increases in acoustic startle induced by intra-BNST infusion of CGRP, as did virally-mediated siRNA knockdown of CRF expression locally within the BNST. Together, these results suggest that the anxiogenic effects of intra-BNST CGRP may be mediated by CRF from BNST neurons acting at local CRFR1 receptors.
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Affiliation(s)
- K S Sink
- Department of Psychiatry and Behavioral Sciences, Yerkes National Primate Center, Emory University, Atlanta, GA 30329, USA
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Ban SJ, Rico CW, Um IC, Kang MY. Antihyperglycemic and antioxidative effects of Hydroxyethyl Methylcellulose (HEMC) and Hydroxypropyl Methylcellulose (HPMC) in mice fed with a high fat diet. Int J Mol Sci 2012; 13:3738-3750. [PMID: 22489179 PMCID: PMC3317739 DOI: 10.3390/ijms13033738] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 03/02/2012] [Accepted: 03/16/2012] [Indexed: 12/03/2022] Open
Abstract
The effect of dietary feeding of hydroxyethyl methylcellulose (HEMC) and hydroxypropyl methylcellulose (HPMC) on the glucose metabolism and antioxidative status in mice under high fat diet conditions was investigated. The mice were randomly divided and given experimental diets for six weeks: normal control (NC group), high fat (HF group), and high fat supplemented with either HEMC (HF+HEMC group) or HPMC (HF+HPMC group). At the end of the experimental period, the HF group exhibited markedly higher blood glucose and insulin levels as well as a higher erythrocyte lipid peroxidation rate relative to the control group. However, diet supplementation of HEMC and HPMC was found to counteract the high fat-induced hyperglycemia and oxidative stress via regulation of antioxidant and hepatic glucose-regulating enzyme activities. These findings illustrate that HEMC and HPMC were similarly effective in improving the glucose metabolism and antioxidant defense system in high fat-fed mice and they may be beneficial as functional biomaterials in the development of therapeutic agents against high fat dietinduced hyperglycemia and oxidative stress.
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Affiliation(s)
- Su Jeong Ban
- Department of Food Science and Nutrition, Kyungpook National University, Daegu 702-701, Korea; E-Mails: (S.J.B.); (C.W.R.)
| | - Catherine W. Rico
- Department of Food Science and Nutrition, Kyungpook National University, Daegu 702-701, Korea; E-Mails: (S.J.B.); (C.W.R.)
| | - In Chul Um
- Department of Natural Fiber Science, Kyungpook National University, Daegu 702-701, Korea; E-Mail:
| | - Mi Young Kang
- Department of Food Science and Nutrition, Kyungpook National University, Daegu 702-701, Korea; E-Mails: (S.J.B.); (C.W.R.)
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Wessman P, Mahlin D, Akhtar S, Rubino S, Leifer K, Kessler V, Håkansson S. Impact of matrix properties on the survival of freeze-dried bacteria. J Sci Food Agric 2011; 91:2518-2528. [PMID: 21445855 DOI: 10.1002/jsfa.4343] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2010] [Revised: 01/10/2011] [Accepted: 01/15/2011] [Indexed: 05/30/2023]
Abstract
BACKGROUND Disaccharides are, in general, the first choice as formulation compounds when freeze-drying microorganisms. Although polysaccharides and other biopolymers are considered too large to stabilise and interact with cell components in the same beneficial way as disaccharides, polymers have been reported to support cell survival. In the present study we compare the efficiency of sucrose and the polymers Ficoll, hydroxyethylcellulose, hydroxypropylmethylcellulose and polyvinylalcohol to support the survival of three bacterial strains during freeze drying. The initial osmotic conditions were adjusted to be similar for all formulations. Formulation characterisation was used to interpret the impact that different compound properties had on cell survival. RESULTS Despite differences in molecular size, both sucrose and the sucrose-based polymer Ficoll supported cell survival after freeze drying equally well. All formulations became amorphous upon dehydration. Scanning electron microscopy and X-ray diffraction data showed that the discerned differences in structure of the dry formulations had little impact on the survival rates. The capability of the polymers to support cell survival correlated with the surface activity of the polymers in a similar way for all investigated bacterial strains. CONCLUSION Polymer-based formulations can support cell survival as effectively as disaccharides if formulation properties of importance for maintaining cell viability are identified and controlled.
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Affiliation(s)
- Per Wessman
- Department of Microbiology, Uppsala Biocenter, Swedish University of Agricultural Sciences, Box 7025, SE-750 07 Uppsala, Sweden.
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Hung SC, Anderson WHK, Albers DR, Langhorst ML, Young SA. Effect of hydroxypropyl methylcellulose on obesity and glucose metabolism in a diet-induced obesity mouse model. J Diabetes 2011; 3:158-67. [PMID: 21599870 DOI: 10.1111/j.1753-0407.2011.00118.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND To investigate the effect of hydroxypropyl methylcellulose (HPMC) on weight loss and metabolic disorders associated with obesity using a high-fat diet-induced obese mouse model under a high-fat diet regimen. METHODS Obese male C57BL/6J (B6) mice were fed either a high-fat (60% kcal), low-fat (10% kcal), or high-fat diet plus HPMC (4% and 8%) for 5 weeks. Body, mesenteric adipose, and liver weights were determined at the end of the study. In addition, plasma cholesterol, insulin, glucose, adiponectin, and leptin were analyzed to determine the effects of HPMC. Hepatic and fecal lipids were measured to determine the effect of HPMC on lipid absorption and metabolism. RESULTS Supplementation of the high-fat diet with 4% and 8% HPMC resulted in significant weight loss in obese B6 mice. Furthermore, significant decreases were seen in adipose (30%-40%), liver weights (15%-26%), and concentrations of plasma cholesterol (13%-20%) and hepatic lipids (13%-36%). Supplementation with 8% HPMC led to significant improvements in glucose homeostasis and leptin concentrations. Reductions in plasma cholesterol, glucose, and insulin levels were strongly correlated with reduced leptin concentrations. Moreover, increases in fecal secretion of total bile acids, sterols, and fats indicated altered fat absorption when HPMC was incorporated in the diet. CONCLUSION The data indicate that HPMC not only reduces body weight, but also normalizes the metabolic abnormalities associated with obesity and suggest that the effects of HPMC on glucose and lipid homeostasis in B6 mice are mediated by improvements in leptin sensitivity resulting from reduced fat absorption.
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Affiliation(s)
- Shao-Ching Hung
- The Dow Chemical Company, Analytical Sciences, Midland, Michigan 48667, USA
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France CP, Weltman RH, Koek W, Cruź CM, McMahon LR. Acute and chronic effects of ramelteon in rhesus monkeys (Macaca mulatta): dependence liability studies. Behav Neurosci 2009; 120:535-41. [PMID: 16768605 DOI: 10.1037/0735-7044.120.3.535] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The acute and chronic effects of ramelteon, an MT1/MT2 receptor agonist, were evaluated in rhesus monkeys (Macaca mulatta) to assess discriminative stimulus effects in comparison with traditional benzodiazepine receptor agonists and to assess physical dependence potential. Discriminative effects of ramelteon were compared with midazolam in untreated monkeys and in diazepam-dependent monkeys that discriminated flumazenil. Dependence potential of ramelteon after daily 1-year administration (and intermittent discontinuation) was evaluated with standard operant procedures. Ramelteon did not produce benzodiazepine-like discriminative stimulus effects at doses up to 10 mg/kg. Long-term treatment or its discontinuation had no significant effect on spontaneous behavior, operant behavior, body weight, motor activity, or posture. These findings suggest that ramelteon is not likely to have benzodiazepine-like abuse or dependence liability.
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Affiliation(s)
- Charles P France
- Department of Pharmacology, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA.
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Abstract
PURPOSE To quantify the hydroxyl radical scavenging activity of a new ophthalmic viscosurgical device (OVD) based on sodium hyaluronate and hydroxypropylmethylcellulose (named VISC28) in comparison with Viscoat, Healon, and Amvisc Plus. METHODS The hydroxyl radicals that represent the principal free-radical species generated during phacoemulsification were produced by the Fenton reaction, and the scavenging activity of the tested viscoelastic substances was evaluated in vitro by the 2-deoxy-D-ribose (2-DR) oxidation method that produces the thiobarbituric acid-malondialdehyde (TBA-MDA), complex. An aliquot of viscosurgical formulation was added to phosphate buffer and mixed with 2-DR, Fe2 +/ethylenediaminetetraacetic acid (EDTA), and H2O2. The sample mix was incubated and thiobarbituric acid-trichloroacetic acid solution was added. The sample was then incubated for 30 min, and a chromatographic analysis was performed to quantify the TBA-MDA complex. The data were expressed as micromoles of MDA per milliliter of sample. RESULTS All tested OVDs showed a marked hydroxyl radical scavenging activity. The MDA level was significantly lower in VISC28 (0.045 +/- 0.007 micromol/ml) compared with Viscoat (0.070 +/- 0.012 micromol/ ml, p < 0.05), Amvisc Plus (0.111 +/- 0.008 micromol/ml, p < 0.001), and Healon (0.175 +/- 0.016 micromol/ml, p < 0.001). A reduced scavenging activity was shown by VISC28 phosphate-buffered solution (PBS) (no TRIS and no sorbitol) compared with VISC28 (p < 0.001). CONCLUSIONS The new OVD, VISC28, showed significantly higher hydroxyl radical inhibition compared with the other viscosurgical formulations. The following rank order for the scavenging activity was established: VISC28 > Viscoat > Amvisc Plus > Healon.
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Valencia-Chamorro SA, Palou L, del Río MA, Pérez-Gago MB. Inhibition of Penicillium digitatum and Penicillium italicum by hydroxypropyl methylcellulose-lipid edible composite films containing food additives with antifungal properties. J Agric Food Chem 2008; 56:11270-8. [PMID: 19012404 DOI: 10.1021/jf802384m] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
New hydroxypropyl methylcellulose (HPMC)-lipid edible composite films containing low-toxicity chemicals with antifungal properties were developed. Tested chemicals were mainly salts of organic acids, salts of parabens, and mineral salts, classified as food additives or generally recognized as safe (GRAS) compounds. Selected films containing food preservatives were used for in vitro evaluation (disk diameter test) of their antifungal activity against Penicillium digitatum (PD) and Penicillium italicum (PI), the most important postharvest pathogens of fresh citrus fruit. Mechanical properties and oxygen (OP) and water vapor permeabilities (WVP) of selected films were also determined. Film disks containing parabens and their mixtures inhibited PD and PI to a higher extent than the other chemicals tested. Among all organic acid salts tested, potassium sorbate (PS) and sodium benzoate (SB) were the most effective salts in controlling both PD and PI. The use of mixtures of parabens or organic acid salts did not provide an additive or synergistic effect for mold inhibition when compared to the use of single chemicals. Barrier and mechanical properties of films were affected by the addition of food preservatives. Results showed that HPMC-lipid films containing an appropriate food additive should promise as potential commercial antifungal edible coatings for fresh citrus fruit.
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Affiliation(s)
- Silvia A Valencia-Chamorro
- Centro de Tecnología Poscosecha, Instituto Valenciano de Investigaciones Agrarias, Moncada, Valencia, Spain
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Huang CQ, Tykocinski M, Stathopoulos D, Cowan R. Effects of steroids and lubricants on electrical impedance and tissue response following cochlear implantation. Cochlear Implants Int 2008; 8:123-47. [PMID: 17854099 DOI: 10.1179/cim.2007.8.3.123] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
The present study examined the effects of steroids and lubricants on electrical impedance and tissue response following cochlear implantation in animal models. Guinea pigs were implanted following either no treatment, or intrascalar injection with dexamethasone, triamcinolone, sodium hyaluronate or saline. Cats were implanted following either no treatment, or intrascalar injection with dexamethasone, triamcinolone or a mixture of triamcinolone with sodium hyaluronate. In guinea pigs, impedance changes and intracochlear tissue response were less for the hyaluronate and saline groups. In cats, impedance in the dexamethasone group increased similar to non-treated cats. Impedance of triamcinolone treated cats remained low for about two months after implantation, before increasing to levels similar to the other groups. Significant fibrous tissue growth was observed histologically. The results of the present study indicate that a single intracochlear application of hyaluronate or triamcinolone may postpone, but will ultimately not prevent the rise in impedance following cochlear implantation.
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Affiliation(s)
- Christie Qi Huang
- Co-operative Research Centre for Cochlear Implant and Hearing Aid Innovation, Melbourne, Victoria, Australia
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Lozano JS, Chay EY, Healey J, Sullenberger R, Klarlund JK. Activation of the epidermal growth factor receptor by hydrogels in artificial tears. Exp Eye Res 2007; 86:500-5. [PMID: 18242602 DOI: 10.1016/j.exer.2007.12.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2007] [Revised: 10/23/2007] [Accepted: 12/10/2007] [Indexed: 01/12/2023]
Abstract
Most formulations of artificial tears include high-molecular weight hydrophilic polymers (hydrogels) that are usually thought to serve to enhance viscosity and to act as demulcents. A few reports have indicated that application of some of the polymers accelerates healing of wounds in epithelia. Since activation of the epidermal growth factor (EGF) receptor is critical for spontaneous corneal epithelial wound healing, we tested commonly used hydrogels for their ability to activate the EGF receptor and enhance closure of wounds. Five structurally unrelated hydrogels used in artificial tears were found to activate the EGF receptor. Importantly, two of the hydrogels enhanced wound healing in an organ culture model. We propose that the efficacy of hydrogels in treating dry eye may be related to their ability to activate the EGF receptor, and that hydrogels are inexpensive, safe agents to promote healing of wounds in the cornea and possibly in other tissues.
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Affiliation(s)
- Jennifer S Lozano
- Ophthalmology and Visual Sciences Research Center, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
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Hong YJ, Turowski M, Lin JT, Yokoyama WH. Simultaneous characterization of bile acid, sterols, and determination of acylglycerides in feces from soluble cellulose-fed hamsters using HPLC with evaporative light-scattering detection and APCI-MS. J Agric Food Chem 2007; 55:9750-9757. [PMID: 17979236 DOI: 10.1021/jf071798+] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The rapid rise in obesity-related diseases has increased interest in oral and dietary agents that disrupt fat metabolism, resulting in the excretion of dietary lipids in the feces. In this study, a rapid and convenient liquid chromatography method to comprehensively analyze fecal lipids in a single injection was developed. An evaporative light-scattering detector (ELSD) for routine analysis or atmosphere pressure chemical ionization tandem mass spectrometry [(+)APCI-MS/MS] for structural confirmation and peak purity was used. The method was applied to characterize lipid components of feces from hamsters fed high-fat diets with either 5% microcrystalline cellulose or 5% hydroxypropyl methylcellulose (HPMC) fibers, to test the effect of HPMC on lipid metabolism. HPMC is a nonfermentable, soluble cellulose fiber. The fecal lipid components identified using this method includes two secondary bile acids, deoxycholic acid, lithocholic acid, and neutral sterols including cholesterol, coprostanol, stigmastanol, and sitosterol. The profile of fecal lipid components was compared between two groups. It was found that the bile acid excretion was increased 2-fold in HPMC-fed hamsters. More interestingly, diacylglycerides and triacylglycerides were detected in feces from hamsters on HPMC-included high-fat diets. We believe that this is the first report of excretion of acylglycerides following neutral soluble fiber feeding.
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Affiliation(s)
- Yun-Jeong Hong
- Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture, Albany, California 94710, USA.
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Reppas C, Swidan SZ, Tobey SW, Turowski M, Dressman JB. Hydroxypropylmethylcellulose significantly lowers blood cholesterol in mildly hypercholesterolemic human subjects. Eur J Clin Nutr 2007; 63:71-7. [PMID: 17882138 DOI: 10.1038/sj.ejcn.1602903] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE To determine the cholesterol-lowering efficacy of hydroxypropylmethylcellulose (HPMC) in mildly hypercholesterolemic humans. SUBJECTS Trial one: entry mean (range) total serum cholesterol values of eight female and four male subjects were 6.48 (5.57-7.51) mmol l(-1) (250 (215-290) mg dl(-1)) and 6.60 (5.57-7.64) mmol l(-1) (255 (215-295) mg dl(-1)), respectively. Trial two: corresponding values for 20 women and 20 men were 5.96 (5.43-6.48) mmol l(-1) 230 (210-250) mg dl(-1)) and 6.05 (5.46-6.63) mmol l(-1) 233 (211-256) mg dl(-1)), respectively. RESULTS Trial one: HPMC decreased (P< or =0.05) total and LDL-cholesterol 9.3 and 15.3% (medium), 16.9 and 23.5% (high) and 13.8 and 19.4% (ultra-high), respectively, over placebo. Trial two: total and LDL-cholesterol decreased (P< or =0.05) throughout the 8 weeks, with mean (weeks 4-8) reductions of 7 and 8% at 5 g day(-1), and 12 and 15% at 15 g day(-1), respectively, over placebo. Adverse effects were minimal. Trial one: medium, high and ultra-high viscosity HPMC at 15 g day(-1) for 1 week each;1-week wash-out between treatments. Trial two: ultra-high viscosity HPMC at 5 or 15 g day(-1) for 8 weeks. CONCLUSIONS HPMC soluble fiber, especially high-viscosity grades, significantly lowers cholesterol at well-tolerated doses, showing promise as a treatment of hypercholesterolemia.
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Affiliation(s)
- C Reppas
- College of Pharmacy, The University of Michigan, Ann Arbor, MI, USA
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Aragona P, Micali A, Paladino G, Ferreri F, Puzzolo D. Effects of tear substitutes on conjunctival epithelium of mice. Ophthalmic Res 2007; 39:265-75. [PMID: 17851267 DOI: 10.1159/000108120] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2006] [Accepted: 04/13/2007] [Indexed: 11/19/2022]
Abstract
AIM The effects of the administration of three tear substitutes on normal conjunctival epithelium of the mouse, with particular regard to goblet cells, were studied. METHODS Three-month-old Swiss CD 1 mice were divided into four groups of 7 animals each. Group 1 was untreated (control). The other animals were treated with the instillation of 5 drops/day for 10 days as follows: group 2, 0.2% sodium hyaluronate (SH); group 3, 0.5% hydroxypropylmethylcellulose (HPMC); group 4, 0.9% NaCl. The entire conjunctiva was processed for light and electron microscopy. A morphometric study was performed to evaluate: the number and size of goblet cells and the number, size and optical density of mucin granules. Furthermore, Alcian blue/periodic acid-Schiff (AB/PAS) staining for goblet cells was carried out. RESULTS The SH-treated group showed that the area and number of goblet cells were similar to the untreated group; the mucin granules were reduced in number and optical density but increased in size. The HPMC-treated group showed a reduced area of goblet cells with reduced optical density of mucin granules. The saline-treated group showed that goblet cells were reduced in area and number; mucin granules showed a reduction in number and optical density and an increased size. The AB/PAS stain showed that each treatment was able to induce a treatment-specific modification of the staining characteristics of goblet cells. CONCLUSION Our results strongly suggest that tear substitutes can induce treatment-specific modifications of the conjunctival epithelium with particular regard to goblet cell structure and ultrastructure.
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Affiliation(s)
- Pasquale Aragona
- Department of Surgical Specialties, Section of Ophthalmology, Azienda Ospedaliera Universitaria Policlinico G. Martino, Messina, Italy.
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Maki KC, Carson ML, Miller MP, Turowski M, Bell M, Wilder DM, Reeves MS. High-viscosity hydroxypropylmethylcellulose blunts postprandial glucose and insulin responses. Diabetes Care 2007; 30:1039-43. [PMID: 17259476 DOI: 10.2337/dc06-2344] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE High-viscosity hydroxypropylmethylcellulose (HV-HPMC) is a modified cellulose fiber that produces a viscous gel in the gastrointestinal tract. Clinical trials demonstrate that consumption of HV-HPMC significantly lowers cholesterol, but limited information has been available on the influence of HV-HPMC on postprandial insulin and glucose responses. The objective of this investigation was to assess the influence of HV-HPMC on postprandial glucose and insulin responses in overweight and obese men and women. RESEARCH DESIGN AND METHODS Participants were 31 overweight or obese men and women without diabetes who underwent three breakfast meal tests in random order, separated by > or = 72 h. Test meals containing 75 g carbohydrate plus 4 or 8 g HV-HPMC or control meals containing 8 g cellulose were delivered in a double-blind fashion. RESULTS Peak glucose was significantly lower (P < 0.001) after both HV-HPMC-containing meals (7.4 mmol/l [4 g] and 7.4 mmol/l [8 g]) compared with the control meal (8.6 mmol/l). Peak insulin concentrations and the incremental areas for glucose and insulin from 0 to 120 min were also significantly reduced after both HV-HPMC doses versus control (all P < 0.01). CONCLUSIONS These findings indicate that HV-HPMC consumption reduces postprandial glucose and insulin excursions, which may favorably alter risks for diabetes and cardiovascular disease.
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Affiliation(s)
- Kevin C Maki
- Provident Clinical Research, 1000 W. 1st St., Bloomington, IN 47403, USA.
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Sumiyoshi H, Ooguchi M, Ooi A, Okagaki T, Higashi-Fujime S. Insight into the mechanism of fast movement of myosin from Chara corallina. ACTA ACUST UNITED AC 2007; 64:131-42. [PMID: 17183547 DOI: 10.1002/cm.20171] [Citation(s) in RCA: 7] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Chara myosin, two-headed plant myosin belonging to class XI, slides F-actin at maximally 60 microm s(-1). To elucidate the mechanism of this fast sliding, we extensively investigated its mechanochemical properties. The maximum actin activated ATPase activity, Vmax, was 21.3 s(-1) head(-1) in a solution, but when myosin was immobilized on the surface, its activity was 57.6 s(-1) head(-1) at 2 mg ml(-1) of F-actin. The sliding velocity and the actin activated ATPase activity were greatly inhibited by ADP, suggesting that ADP dissociation was the rate limiting step. With the extensive assay of motility by varying the surface density, the duty ratio of Chara myosin was found to be 0.49-0.44 from velocity measurements and 0.34 from the landing rate analysis. At the surface density of 10 molecules microm(-2), Chara myosin exhibited pivot movement under physiological conditions. Based on the results obtained, we will discuss the sliding mechanism of Chara myosin according to the working stroke model in terms of its physiological aspects. aspects.
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Affiliation(s)
- Hiroki Sumiyoshi
- Department of Molecular Biology, School of Science, Nagoya University, Chikusaku Nagoya, Japan
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Sebti I, Chollet E, Degraeve P, Noel C, Peyrol E. Water sensitivity, antimicrobial, and physicochemical analyses of edible films based on HPMC and/or chitosan. J Agric Food Chem 2007; 55:693-9. [PMID: 17263462 DOI: 10.1021/jf062013n] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Several properties of chitosan films associated or not with hydroxypropylmethylcellulose polymer (HPMC) and HPMC films incorporating or not nisin and/or milk fat were studied. Nisin addition at a level of 250 microg mL-1 and likewise chitosan at 1% (w/v) concentration were efficient for total inhibiting Aspergillus niger and Kocuria rhizophila food deterioration microorganisms. HPMC and chitosan films were transparent, whereas nisin and/or fat incorporation induced a 2-fold lightness parameter increase and, consequently, involved more white films. Measurements of tensile strength, as well as ultimate elongation, showed that chitosan and HPMC initial films were elastic and flexible. High thermal treatments and additive incorporation induced less elastic and more plastic films. Water vapor transmission as far as total water desorption rates suggested that chitosan films were slightly sensitive to water. Water transfer was decreased by <60% as compared with other biopolymer films. Regarding its hydrophobic property, the capacity of fat to improve film water barrier was very limited.
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Affiliation(s)
- Issam Sebti
- Laboratoire de Recherche en Génie Industriel Alimentaire EA 3733, IUT A, Département Génie Biologique, Université Lyon 1, Rue Henri de Boissieu, F-01060 Bourg-en-Bresse cedex 09, France.
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Waseem M, Rustam N. Intraocular pressure after phacoemulsification using hydroxypropyl methylcellulose and sodium hyaluronate as viscoelastics. J Ayub Med Coll Abbottabad 2007; 19:42-5. [PMID: 17867479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
BACKGROUND Phacoemulsification and intraocular lens (IOL) implantation has resulted in early visual rehabilitation, increased wound stability and improved refractive results. Viscoelastic substances (VES) are important adjuncts in this type of surgery. Use of VES in phacoemulsification can be associated with adverse effects, the most common and potentially dangerous of which is the transient rise in intraocular pressure (IOP) in post-operative period. To evaluate the effects of viscoelastic substances on post-operative IOP after phacoemulsification with implantation of intraocular lens, a cross-sectional comparative, prospective study was conducted in the department of Ophthalmology, Combined Military Hospital, Peshawar, Pakistan, from October 2003 to March 2004. METHODS One hundred patients were randomized into two groups of 50 each. Phacoemulsification with implantation of intraocular lens was performed in all the patients. 2% Hydroxypropyl Methylcellulose (HPMC) was used in one group and 1% Sodium Hyaluronate (NaHa) was used in the other group. IOP was measured pre-operatively as well as 24 hours and 7 days post-operatively. RESULTS There was no significant difference in the pre-operative intraocular pressure between the two groups (p=0.483). Twenty four hours after surgery, the mean IOP increased by 2.84+/-SD 2.12 mm Hg in 2% Hydroxypropyl Methylcellulose group and 4.54+/-2.07 mm Hg in 1% Sodium Hyaluronate group. The increase was significantly higher in 1% Sodium Hyaluronate group as compared to 2% Hydroxypropyl Methylcellulose group (p=0.003). Seven days after surgery the mean intraocular pressure returned to near pre-operative levels in both the groups. CONCLUSION Sodium Hyaluronate causes significantly higher increase in intraocular pressure in early post-operative period after cataract surgery inspite of maximum aspiration of viscoelastic substance from the eye following phacoemulsification surgery.
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Rando RF, Obara S, Osterling MC, Mankowski M, Miller SR, Ferguson ML, Krebs FC, Wigdahl B, Labib M, Kokubo H. Critical design features of phenyl carboxylate-containing polymer microbicides. Antimicrob Agents Chemother 2006; 50:3081-9. [PMID: 16940105 PMCID: PMC1563534 DOI: 10.1128/aac.01609-05] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Recent studies of cellulose-based polymers substituted with carboxylic acids like cellulose acetate phthalate (CAP) have demonstrated the utility of using carboxylic acid groups instead of the more common sulfate or sulfonate moieties. However, the pK(a) of the free carboxylic acid group is very important and needs careful selection. In a polymer like CAP the pK(a) is approximately 5.28. This means that under the low pH conditions found in the vaginal lumen, CAP would be only minimally soluble and the carboxylic acid would not be fully dissociated. These issues can be overcome by substitution of the cellulose backbone with a moiety whose free carboxylic acid group(s) has a lower pK(a). Hydroxypropyl methylcellulose trimellitate (HPMCT) is structurally similar to CAP; however, its free carboxylic acids have pK(a)s of 3.84 and 5.2. HPMCT, therefore, remains soluble and molecularly dispersed at a much lower pH than CAP. In this study, we measured the difference in solubility and dissociation between CAP and HPMCT and the effect these parameters might have on antiviral efficacy. Further experiments revealed that the degree of acid substitution of the cellulose backbone can significantly impact the overall efficacy of the polymer, thereby demonstrating the need to optimize any prospective polymer microbicide with respect to pH considerations and the degree of acid substitution. In addition, we have found HPMCT to be a potent inhibitor of CXCR4, CCR5, and dual tropic strains of human immunodeficiency virus in peripheral blood mononuclear cells. Therefore, the data presented herein strongly support further evaluation of an optimized HPMCT variant as a candidate microbicide.
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Affiliation(s)
- Robert F Rando
- Novaflux Biosciences, Inc., 1 Wall Street, Princeton, New Jersey 08540, USA.
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Yamada H, Mitarai S, Aguiman L, Matsumoto H, Fujiki A. Preparation of mycobacteria-containing artificial sputum for TB panel testing and microscopy of sputum smears. Int J Tuberc Lung Dis 2006; 10:899-905. [PMID: 16898375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023] Open
Abstract
SETTING Panel testing, blinded cross rechecking and on-site evaluation are the three methods for external quality assessment (EQA) of acid-fast bacilli (AFB) smear microscopy. Panel testing can provide data on laboratory capabilities prior to implementing a rechecking programme, assess the current status of laboratory performance and detect problems associated with diagnostic performance. Thus far, two methods for preparing panel test slides have been reported: these use real AFB-positive and -negative sputum treated with sodium hydroxide (NaOH) or N-acetyl-L-cysteine (NALC). OBJECTIVE To evaluate the above methods and to develop a new method to prepare panel test slides with artificial sputum. DESIGN Panel test slides were prepared using the NaOH and NALC methods. New artificial sputum preparation methods were developed and examined using a cultured monocyte cell line, cultured avirulent mycobacteria and methylcellulose or polyacrylamide gel as substrate. Smears prepared by the four methods were compared. RESULTS Panel test slides prepared with NaOH and NALC methods are not macroscopically or microscopically similar to real smears. Our new artificial sputum is similar to real sputum in viscosity and macroscopic and microscopic appearance; it is also consistent in panel positivity grades. CONCLUSION The artificial sputum described here could contribute to the EQA and training in tuberculosis laboratories or microscopy centres.
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Affiliation(s)
- H Yamada
- Pathology Division, Mycobacterium Reference Center, Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Kiyose, Tokyo, Japan.
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Aras C, Baslar Z, Unal M, Horoz H. Comparison of the effect of Healon, Healon GV, Healon 5, Viscoat, and Ocucoat on platelet aggregation under in vitro conditions. Eur J Ophthalmol 2006; 16:306-10. [PMID: 16703551 DOI: 10.1177/112067210601600218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE To study the effect of Healon, Healon GV, Healon 5, Viscoat, and OcuCoat on platelet aggregation under in vitro conditions. METHODS Ocular viscoelastic devices including Healon, Healon GV, Healon 5, Viscoat, and OcuCoat were studied to investigate the effect of these agents on platelet aggregation under in vitro conditions. The experiments were performed by using platelet-rich plasma with an aggregometer. Aggregation was induced with three different agonists including 5''-adeno-sinediphosphate (ADP), epinephrine (EPI), and collagen (Col ). The results were obtained as a percentage of maximal aggregation and compared with controls using one-way analysis of variance (ANOVA) test. RESULTS The tests with ADP as aggregating agent revealed that the percentages of maximal aggregation were a mean of 75 +/- 4.35% for ADP only, 67 +/- 4.35% for Healon, 59.33 +/- 3.51% for Healon GV, 70 +/- 3% for Healon 5, 58 +/- 3.46% for Viscoat, and 64 +/- 2% for OcuCoat. Kruskal-Wallis one-way ANOVA test revealed no significant decrease in the percentage of maximal aggregation for all tested substances. With EPI, aggregation was induced in all control samples with a mean of 80.66 +/- 2.08%. The mean percentage of maximal aggregation was 67 +/- 3% for Healon, 77.66 +/- 4.04% for Healon GV, 77 +/- 4% for Healon 5, 80.6 +/- 4.04% for Viscoat, and 65 +/- 5% for OcuCoat. Statistical analysis showed no significant difference. With collagen, maximum aggregation was 74 +/- 5.29% for controls, 65 +/- 4.35% for Healon, 54 +/- 2% for Healon GV, 51 +/- 2.64% for Healon 5, 59 +/- 2% for Viscoat, and 72.66 +/- 1.52% for OcuCoat. Kruskal -Wallis one-way ANOVA test revealed no significant change in the percentage of maximal aggregation for all tested substances in the experiments. CONCLUSIONS Ophthalmic viscosurgical devices like Healon, Healon GV, Healon 5, and Viscoat that contain glycosaminoglycans and OcuCoat that contains hydroxypropyl methylcellulose have inhibitory effects on platelet aggregation but the effect is not statistically significant and there is no difference among the ocular viscoelastic devices in regard to inhibitory effect on platelet aggregation.
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Affiliation(s)
- C Aras
- Department of Ophthalmology, Istanbul University, Istanbul, Turkey.
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Abstract
PURPOSE To use an experimental animal model to study the effect on intraocular pressure (IOP) of methylcellulose 2% application in trabeculectomy, followed by histologic assessment. METHODS Trabeculectomy was performed on albino rabbits' eyes. The study comprised two groups, each group consisting of five rabbits. The right eyes were subjected to trabeculectomy, and the left eyes served as the control. In both groups 1 and 2, trabeculectomy was performed in the right eyes, but in group 2, trabeculectomy was followed by injection of methylcellulose 2% into the anterior chamber. The methylcellulose was allowed to pass through the trabeculectomy site into the subconjunctival space, and an extra amount was injected by the same cannula under the conjunctiva in the area of the trabeculectomy from the edge of the periotomy. Measurement of IOP was performed with a Shiotz tonometer once weekly for 4 weeks. Specimens were obtained from the operative site, and semithin sections were prepared, stained with toluidine blue, and examined by light microscopy (LM). RESULTS A significant difference in the decrease of IOP (P<0.0001) was observed between the two groups after 4 weeks of surgery. During the 4 weeks after trabeculectomy, the mean IOP was 18.2+/-0.45 mm Hg without methylcellulose injection and 18.3+/-0.77 mm Hg in the control eyes, and 9.8+/-0.84 mm Hg with methylcellulose injection, 18.25+/-0.7 mm Hg in the control eyes. The histopathological findings in group 1 (without methylcellulose injection) showed the subscleral spaces to be less fenestrated, with deposition of dense collagen bundles intermingled with the fibrocytes, some of which were active with prominent mitosis. In contrast, in group 2 (injected with methylcellulose), the subscleral space appeared fenestrated with irregularly and widely spaced segmented collagen bundles. CONCLUSIONS Methylcellulose may have antihealing properties that serve to decrease IOP in trabeculectomy. Although more work is needed in humans, because human tissue may be different in its response to the same procedure, the use of methylcellulose could be very promising.
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Affiliation(s)
- Ayman A M Shouman
- Department of Ophthalmology, Research Institute of Ophthalmology, Giza, Egypt.
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Watanabe H, Miyazaki H. A new approach to correct the QT interval for changes in heart rate using a nonparametric regression model in beagle dogs. J Pharmacol Toxicol Methods 2006; 53:234-41. [PMID: 16297641 DOI: 10.1016/j.vascn.2005.09.003] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2005] [Accepted: 09/14/2005] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Over- and/or under-correction of QT intervals for changes in heart rate may lead to misleading conclusions and/or masking the potential of a drug to prolong the QT interval. This study examines a nonparametric regression model (Loess Smoother) to adjust the QT interval for differences in heart rate, with an improved fitness over a wide range of heart rates. METHODS 240 sets of (QT, RR) observations collected from each of 8 conscious and non-treated beagle dogs were used as the materials for investigation. The fitness of the nonparametric regression model to the QT-RR relationship was compared with four models (individual linear regression, common linear regression, and Bazett's and Fridericia's correlation models) with reference to Akaike's Information Criterion (AIC). Residuals were visually assessed. RESULTS The bias-corrected AIC of the nonparametric regression model was the best of the models examined in this study. Although the parametric models did not fit, the nonparametric regression model improved the fitting at both fast and slow heart rates. DISCUSSION The nonparametric regression model is the more flexible method compared with the parametric method. The mathematical fit for linear regression models was unsatisfactory at both fast and slow heart rates, while the nonparametric regression model showed significant improvement at all heart rates in beagle dogs.
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Affiliation(s)
- Hiroyuki Watanabe
- Biostatistics, Clinical Development Institute, Banyu Pharmaceutical Co., Ltd., AIG Kabutocho Building, 5-1, Nihombashi-Kabutocho, Chuo-ku, Tokyo 103-0026, Japan.
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Abstract
PURPOSE The femtosecond laser (Intralase) may provide advantages for dissecting a thin, uniform thickness posterior lamellar disk of donor tissue to be used for endothelial transplantation. We investigated the use of the Intralase to dissect the donor cornea from the posterior side to better obtain a thin and uniform lamellar disk. We investigated the use of a viscoelastic "cushion" to protect the endothelium during applanation and laser delivery. METHODS Human eye bank donor buttons were placed endothelial side up, covered with a thin coat of viscoelastic, and brought into contact with the Intralase applanation lens. A 7-mm diameter, 100-microm lamellar disk was cut from the endothelial side. The endothelial viability after these procedures was determined using a live cell/dead cell assay. Controls were designed to assess the endothelial viability after applanation and laser application using only a balanced salt solution (BSS) cushion instead of viscoelastic material. Additionally, applanation without lasering using either BSS or a viscoelastic cushion was studied. RESULTS The average endothelial cell loss in the laser experiment sets were 10% (n = 5, range of 4-17%, Sodium Hyaluronate), 14% (n = 5, range of 7-19%, Sodium Hyaluronate-Sodium Chondroitin) and 6% (n = 5, range of 3-11%, Hydroxypropylmethyl-cellulose). In the controls, laser and applanation with BSS resulted in an average endothelial loss of 18% (n = 5, range of 14-26%). Applanation alone without laser dissection resulted in cell loss of 9% (n = 5, range of 7-12%) using BSS and 9% (n = 6, range 1-42%) Hydroxypropylmethyl-cellulose. CONCLUSIONS The technique of using a viscoelastic "cushion" to protect endothelial cells from damage during posterior laser dissection prior to transplantation is promising. Viscoelastic coating protects the endothelial layer from damage from the coupling lens better than a layer of BSS. The lasering process, however, causes damage in addition to applanation with the laser lens. Further studies are warranted to optimize reproducibility of endothelial cell survival and evaluate the smoothness of stromal dissections in the posterior cornea.
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Hyun JJ, Chun HR, Chun HJ, Jeen YT, Baeck CW, Yu SK, Kim YS, Lee HS, Um SH, Lee SW, Choi JH, Kim CD, Ryu HS, Hyun JH. Comparison of the characteristics of submucosal injection solutions used in endoscopic mucosal resection. Scand J Gastroenterol 2006; 41:488-92. [PMID: 16635919 DOI: 10.1080/00365520500325994] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Submucosal injection is used to prevent complications, such as perforation, during endoscopic mucosal resection (EMR). Since injection of normal saline produces mucosal elevation of short duration, repeated injection is needed for extensive resection. To overcome this limitation, various submucosal injection solutions have been developed but there are few data comparing their efficacy. This study was therefore conducted to compare the physical and chemical properties and the duration of mucosal elevation of various submucosal injection solutions. MATERIAL AND METHODS A fresh transverse colon specimen acquired from a mongrel was used. Experiments were repeated four times. To compare the efficacy of mucosal elevation, 1 ml of each solution was injected into the submucosa: 0.9% NaCl, 20% mannitol, 0.1% sodium hyaluronate, 0.3% hydroxypropyl methylcellulose (HPMC), and 2% fibrinogen. Physical and chemical properties such as viscosity and osmolarity were compared. RESULTS The heights of initial mucosal elevations were 6.52+/-0.26 mm, 6.87+/-0.05 mm, 6.92+/-0.09 mm, 6.90+/-0.08 mm, and 6.90+/-0.08 mm for normal saline, mannitol, sodium hyaluronate, HPMC, and fibrinogen, respectively. Whereas injection of normal saline took about 20 min and mannitol about 30 min for the initial elevation to be reduced to more than half the initial height, it took more than 60 min for all the other agents. A correlation was found between the duration of mucosal elevation and viscosity but not with osmolarity. CONCLUSIONS The mucosal elevation lasted longer with sodium hyaluronate, HPMC, and fibrinogen than with mannitol or normal saline, and this seems to be due to the viscosity rather than the osmolarity of each solution.
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Affiliation(s)
- Jong Jin Hyun
- Department of Internal Medicine, Institute of Digestive Disease and Nutrition, Korea University College of Medicine, Seoul, Korea
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Salman H, Bessler H, Bergman M, Fibach E, Djaldetti M. Functional hypersplenism in mice induced by adoptive transfer of syngeneic spleen cells. Exp Biol Med (Maywood) 2006; 231:112-6. [PMID: 16380652 DOI: 10.1177/153537020623100114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Investigation of peripheral blood cell count alterations in cases with hypersplenism, and an understanding of the relationship between splenic function and hematopoietic cell production require suitable experimental animal models. Previously described methods are either traumatic or require surgical intervention. We suggest a relatively simple method for achievement of a state mimicking hypersplenism in mice by intraperitoneal inoculation of syngeneic spleen cells. Mice were inoculated intraperitoneally with 3 x 10(7) splenocytes suspended in 0.3 ml phosphate buffered saline (PBS). After 2 months, the inoculated animals showed a progressive decrease in the peripheral white blood cell (WBC) counts and hyperplastic bone marrow that persisted until the experimental end point (7 months). Five days after inoculation of splenocytes stained with carboxy-fluorescein diacetate succinimidyl ester (CFSE), the majority of the stained cells was present in the peritoneal cavity (33%) and in the liver (13%), whereas the percentage of stained cells in the peripheral blood and the spleen cell suspension was negligible. The mitogen response of the peripheral blood mononuclear cells (PBMC) from treated mice to concanavalin A (Con A) remained unaltered. Splenocyte-inoculated mice that were further splenectomized did not show leukocytosis after splenectomy, as was observed in animals in which the spleen was removed without any pretreatment. The lack of any signs of discomfort in animals from the study group, in comparison with the visibly ill appearance and even death of mice in which hypersplenism was achieved by repeated injections of methylcellulose (MC), which served as controls, favors the convenience of the method.
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Affiliation(s)
- Hertzel Salman
- Department of Medicine C, Rabin Medical Center-Golda Campus, Petah-Tiqva, Israel
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41
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Takashima K, Mizukawa Y, Morishita K, Okuyama M, Kasahara T, Toritsuka N, Miyagishima T, Nagao T, Urushidani T. Effect of the difference in vehicles on gene expression in the rat liver--analysis of the control data in the Toxicogenomics Project Database. Life Sci 2005; 78:2787-96. [PMID: 16360708 DOI: 10.1016/j.lfs.2005.11.010] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2005] [Accepted: 11/01/2005] [Indexed: 11/21/2022]
Abstract
The Toxicogenomics Project is a 5-year collaborative project by the Japanese government and pharmaceutical companies in 2002. Its aim is to construct a large-scale toxicology database of 150 compounds orally administered to rats. The test consists of a single administration test (3, 6, 9 and 24 h) and a repeated administration test (3, 7, 14 and 28 days), and the conventional toxicology data together with the gene expression data in liver as analyzed by using Affymetrix GeneChip are being accumulated. In the project, either methylcellulose or corn oil is employed as vehicle. We examined whether the vehicle itself affects the analysis of gene expression and found that corn oil alone affected the food consumption and biochemical parameters mainly related to lipid metabolism, and this accompanied typical changes in the gene expression. Most of the genes modulated by corn oil were related to cholesterol or fatty acid metabolism (e.g., CYP7A1, CYP8B1, 3-hydroxy-3-methylglutaryl-Coenzyme A reductase, squalene epoxidase, angiopoietin-like protein 4, fatty acid synthase, fatty acid binding proteins), suggesting that the response was physiologic to the oil intake. Many of the lipid-related genes showed circadian rhythm within a day, but the expression pattern of general clock genes (e.g., period 2, arylhydrocarbon nuclear receptor translocator-like, D site albumin promoter binding protein) were unaffected by corn oil, suggesting that the effects are specific for lipid metabolism. These results would be useful for usage of the database especially when drugs with different vehicle control are compared.
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Affiliation(s)
- Kayoko Takashima
- Toxicogenomics Project, National Institute of Health Sciences, Setagaya-Ku, Tokyo, 158-8501, Japan
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Abstract
The aim of this study was to establish a method for analysis of tear film stability and thereby to investigate the effects of lubricants on corneal surface regularity and corneal epithelial damage in anesthetized rabbits with the eye held open. Saline-instilled and noninstilled eyes manifested a time-dependent increase in the corneal surface regularity index (SRI). In contrast, 0.1% hyaluronic acid (HA) prevented the increase in the SRI for up to 20 min after instillation. Methylene blue uptake into the damaged cornea was significantly greater in eyes that received saline than in those treated with HA. Whereas eyes instilled with 0.5% methylcellulose (MC) or 0.35% sodium carboxymethylcellulose (CMC) manifested an increase in the SRI similar to that apparent in those that received saline, 1.0% chondroitin sulfate (CS) prevented the increase in the SRI for up to 10 min after instillation. In conclusion, we have established a method for analysis of tear film stability in rabbits. Our results suggest that tear film stability is closely related to corneal surface damage and that topical instillation of 0.1% HA or 1.0% chondroitin sulfate warrants further investigation as a potential treatment for patients with dry eye.
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Affiliation(s)
- Shin-ichiro Hirai
- Research and Development Center, Santen Pharmaceutical Co., Ltd., Nara, Japan.
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Shaevitz JW, Lee JY, Fletcher DA. Spiroplasma swim by a processive change in body helicity. Cell 2005; 122:941-5. [PMID: 16179261 DOI: 10.1016/j.cell.2005.07.004] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2005] [Revised: 06/19/2005] [Accepted: 07/08/2005] [Indexed: 11/21/2022]
Abstract
Microscopic organisms must rely on very different strategies than their macroscopic counterparts to swim through liquid. To date, the best understood method for prokaryotic swimming employs the rotation of flagella. Here, we show that Spiroplasma, tiny helical bacteria that infect plants and insects, use a very different approach. By measuring cell kinematics during free swimming, we find that propulsion is generated by the propagation of kink pairs down the length of the cell body. A processive change in the helicity of the body creates these waves and enables directional movement.
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Affiliation(s)
- Joshua W Shaevitz
- Department of Integrative Biology, University of California, Berkeley, 459 Evans Hall, Berkeley, California 94720, USA.
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Katagiri Y, Iwasaki T, Ishikawa T, Yamakawa N, Suzuki H, Usui M. Application of Thermo-setting Gel as Artificial Vitreous. Jpn J Ophthalmol 2005; 49:491-496. [PMID: 16365795 DOI: 10.1007/s10384-005-0255-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2004] [Accepted: 04/27/2005] [Indexed: 10/25/2022]
Abstract
PURPOSE In this study, we produced a rabbit model and investigated the safety of intravitreous injection of a thermo-setting gel (TG) to determine whether TG can be used as artificial vitreous. METHODS Ten male Japanese white rabbits were used. After performing vitrectomy in a unilateral eye, we injected 1 ml of WTG-127 into the vitreous cavity. The contralateral control eye was not given ophthalmic solution or surgery. Each eye was examined and intraocular pressure (IOP) and the electroretinogram (ERG) were evaluated. On day 28, all eyes were enucleated and examined. RESULTS No abnormal findings and no elevation of IOP were observed. On the ERG, no significant difference in the latency and amplitude of either the a wave or b wave was observed. Histopathological examination of the retinal tissue showed no abnormalities. In the presence of a retinal tear, under the detached retina a drift of TG through the tear was observed in a few animals. CONCLUSIONS In a rabbit model, the safety of using an intravitreous injection of thermo-setting gel as artificial vitreous was confirmed by ophthalmoscopic, electrophysiological, and histological studies for a relatively short observation period. However, TG injection cannot be expected to provide a tamponade effect.
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Affiliation(s)
- Yoshiaki Katagiri
- Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan.
| | - Takuya Iwasaki
- Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan
| | - Tomoaki Ishikawa
- Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan
| | - Naoyuki Yamakawa
- Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan
| | | | - Masahiko Usui
- Department of Ophthalmology, Tokyo Medical University, Tokyo, Japan
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Shukla S, Mishra A, Fu P, MacLennan GT, Resnick MI, Gupta S. Up-regulation of insulin-like growth factor binding protein-3 by apigenin leads to growth inhibition and apoptosis of 22Rv1 xenograft in athymic nude mice. FASEB J 2005; 19:2042-4. [PMID: 16230333 DOI: 10.1096/fj.05-3740fje] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Epidemiological studies suggest that increased intake of fruits and vegetables may be associated with a reduced risk of prostate cancer. Apigenin (4', 5, 7,-trihydroxyflavone), a common dietary flavonoid abundantly present in fruits and vegetables, has shown remarkable anti-proliferative effects against various malignant cell lines. However, the mechanisms underlying these effects remain to be elucidated. We investigated the in vivo growth inhibitory effects of apigenin on androgen-sensitive human prostate carcinoma 22Rv1 tumor xenograft subcutaneously implanted in athymic male nude mice. Apigenin was administered to mice by gavage at doses of 20 and 50 mug/mouse/day in 0.2 ml of a vehicle containing 0.5% methyl cellulose and 0.025% Tween 20 in two different protocols. In the first protocol, apigenin was administered for 2 wk before inoculation of tumor and was continued for 8 wk, resulting in significant inhibition of tumor volume by 44 and 59% (P<0.002 and 0.0001), and wet weight of tumor by 41 and 53% (P<0.05), respectively. In the second protocol, administration of apigenin began 2 wk after tumor inoculation and continued for 8 wk; tumor volume and wet weights of tumor were reduced by 39 and 53% (P<0.01 and 0.002) and 31 and 42% (P<0.05), respectively. The tumor inhibitory effect of apigenin was more pronounced in the first protocol of extended treatment, which was associated with increased accumulation of human IGFBP-3 in mouse serum along with significant increase in IGFBP-3 mRNA and protein expression in tumor xenograft. Apigenin intake by these mice also resulted in simultaneous decrease in serum IGF-I levels and induction of apoptosis in tumor xenograft. Importantly, tumor growth inhibition, induction of apoptosis, and accumulation of IGFBP-3 correlated with increasing serum and tumor apigenin levels. In both studies, animals did not exhibit any signs of toxicity or reduced food consumption. In cell culture studies, apigenin treatment resulted in cell growth inhibition and induction of apoptosis, which correlated with increased accumulation of IGFBP-3 in culture medium and cell lysate. These effects were associated with significant reduction in IGF-I secretion; inhibition of IGF-I-induced cell cycle progression and insulin receptor substrate-1 (IRS-1) tyrosine phosphorylation, along with an increase in sub-G1 peak by apigenin. Further, treatment of cells with IGFBP-3 antisense oligonucleotide reversed these effects and attenuated apigenin-mediated inhibition of IRS-1 phosphorylation conferring inhibitory effects of apigenin on IGF-signaling. This study presents the first evidence that the in vitro and in vivo growth inhibitory effects of apigenin involve modulation of IGF-axis signaling in prostate cancer.
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MESH Headings
- Adaptor Proteins, Signal Transducing/metabolism
- Administration, Oral
- Animals
- Antineoplastic Agents/pharmacology
- Apigenin/physiology
- Apoptosis
- Cell Cycle
- Cell Line, Tumor
- Cell Proliferation
- Culture Media/metabolism
- Dose-Response Relationship, Drug
- Insulin-Like Growth Factor Binding Protein 3/biosynthesis
- Insulin-Like Growth Factor Binding Protein 3/chemistry
- Insulin-Like Growth Factor Binding Protein 3/metabolism
- Insulin-Like Growth Factor I/biosynthesis
- Male
- Methylcellulose/pharmacology
- Mice
- Mice, Nude
- Models, Biological
- Neoplasm Transplantation
- Oligonucleotides, Antisense/chemistry
- Phosphorylation
- Polysorbates/pharmacology
- Prostatic Neoplasms/pathology
- RNA, Messenger/metabolism
- Receptor, IGF Type 1/metabolism
- Shc Signaling Adaptor Proteins
- Signal Transduction
- Src Homology 2 Domain-Containing, Transforming Protein 1
- Time Factors
- Tyrosine/chemistry
- Tyrosine/metabolism
- Up-Regulation
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Affiliation(s)
- Sanjeev Shukla
- Department of Urology, Case Western Reserve University, Cleveland, Ohio, USA.
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46
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Bartolović K, Balabanov S, Berner B, Bühring HJ, Komor M, Becker S, Hoelzer D, Kanz L, Hofmann WK, Brümmendorf TH. Clonal heterogeneity in growth kinetics of CD34+CD38- human cord blood cells in vitro is correlated with gene expression pattern and telomere length. Stem Cells 2005; 23:946-57. [PMID: 15941854 DOI: 10.1634/stemcells.2004-0311] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Human hematopoietic stem cells (HSCs) are characterized by an extensive proliferative capacity that decreases from fetal liver to cord blood (CB) to adult bone marrow. In previous studies, it was demonstrated that the proliferative capacity of individual CD34+CD38- HSC clones is correlated with their growth kinetics in vitro and that HSC turnover in vivo can be estimated by telomere-length measurements. The present study was aimed at the characterization of the clonal composition of CD34+CD38- human umbilical CB cells in terms of growth kinetics, telomere length, and gene expression profile. For this purpose, individual CD34+CD38- CB cells were sorted into 96-well plates containing serum-free medium supplemented with six growth factors. During expansion, cell numbers in each individual well were scored in 3-day intervals. Once sufficient cell numbers were achieved, telomere length was measured by flow fluorescence in situ hybridization (flow FISH). In a second set of experiments, gene expression and colony-forming capacity were analyzed in slowly growing clones as compared with fast-growing clones, using linear amplification and oligonucleotide microarrays (HG-U133A; Affymetrix). Individual CD34+CD38- cells from CB displayed an extensive functional heterogeneity in growth kinetics. Among highly proliferative clones, the most slowly growing clones were characterized by the longest telomeres. Furthermore, significant differences in gene expression were detected between slow- and fast-growing clones, whereas no significant difference in colony-forming capacity was observed. These data provide further evidence for a functional hierarchy in the human HSC compartment and suggest a link between telomere length and proliferation capacity of individual HSC clones.
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Affiliation(s)
- Kerol Bartolović
- Department of Oncology and Hematology, University Hospital Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
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47
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Cristofori PG, Crivellente FA, Faustinelli I, Lanzoni AR, Lazzarini C, Vecchiato E, Andreoli M, Turton JA, Zancanaro C, Crespi FM. Involvement of the nitric oxide system in the anti-atherosclerotic potential of lacidipine in the ApoE-deficient mouse: a morphological, functional, and electrochemical study. Toxicol Pathol 2005; 32:493-9. [PMID: 15223775 DOI: 10.1080/01926230490483351] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The present study investigated the anti-atherosclerotic activity of lacidipine, a calcium antagonist with antioxidant properties in apoE-deficient mice. These mice show widespread vascular lesions which closely resemble the inflammatory-fibrous plaques seen in humans in atherosclerosis. Mice were fed a Western-type diet (WTD), and treated for 8 weeks with either vehicle or lacidipine at 3 or 10 mg/kg/day. In parallel with histological studies of atherosclerotic lesions in the aorta, functional studies on vascular acetylcholine (ACh) reactivity and analysis of voltammetric levels of nitric oxide (NO) were performed. Recent work has suggested that dihydropyridines (DHPs) modulate vascular relaxation via an increase in the release of NO. Lacidipine treatment had no effect on the plasma lipid profile. However, a significant (p < 0.01) dose-related reduction of 36.4% and 43.3% of the aortic lesion area in respect to methocel-treated mice was observed. Moreover, the aortic ring from control apoE-deficient mice fed a WTD for 8 weeks showed a lower relaxation in response to ACh in comparison to wild-type C57BL/6J mice; on the contrary, lacidipine-treated apoE-deficient mice lacidipine-treated displayed a response similar to that of wildtype C57BL/6J mice. Voltammetric analyses demonstrated a significant decrease of NO release in apoE-deficient mice, while lacidipine-treated mice showed enhanced activity of the NO system. We conclude that lacidipine reduced the extent of atherosclerotic area in hypercholesterolemic apoE-deficient mice, and this reduction may be associated with the capacity of the drug to maintain endothelial NO levels at concentrations useful to protect against vascular damage.
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Affiliation(s)
- Patrizia G Cristofori
- Safety Assessment Department, Pathology, Glaxo Smith Kline Research Centre, Verona, Italy.
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Abstract
To prepare composite films from biopolymers with anti-listerial activity and moisture barrier properties, the antimicrobial efficiency of chitosan-hydroxy propyl methyl cellulose (HPMC) films, chitosan-HPMC films associated with lipid, and chitosan-HPMC films chemically modified by cross-linking were evaluated. In addition, the physicochemical properties of composite films were evaluated to determine their potential for food applications. The incorporation of stearic acid into the composite chitosan-HPMC film formulation decreased water sensitivity such as initial solubility in water and water drop angle. Thus, cross-linking of composite chitosan-HPMC, using citric acid as the cross-linking agent, led to a 40% reduction in solubility in water. The water vapor transfer rate of HPMC film, approximately 270 g x m(-2) x day(-1) x atm(-1), was improved by incorporating chitosan and was further reduced 40% by the addition of stearic acid and/or cross-linking. Anti-listerial activity of films was determined on solid medium by a numeration technique. Chitosan-HPMC-based films, with and without stearic acid, inhibited the growth of Listeria monocytogenes completely. On the other hand, a loss of antimicrobial activity after chemical cross-linking modification was observed. FTIR and 13C NMR analyses were then conducted in order to study a potential chemical modification of biopolymers such as a chemical reaction with the amino group of chitosan. To complete the study, the mechanical properties of composite films were determined from tensile strength assays.
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Affiliation(s)
- Heike Möller
- Laboratoire de Chimie des Substances Végétales, Centre de Recherche en Chimie Moléculaire, Institut du Pin, Université Bordeaux 1, 351 cours de la Libération, 33405 Talence, France
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Keller SL, Wood RD, Jefferson BJ, Jacobs RM. Use of a commercial methylcellulose medium with and without recombinant bovine granulocyte colony-stimulating factor for culturing bovine bone marrow cells. Can J Vet Res 2004; 68:157-9. [PMID: 15188963 PMCID: PMC1142162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
A commercial methylcellulose culture medium, with and without the addition of recombinant bovine granulocyte colony-stimulating factor (rbG-CSF), was utilized for culturing bovine bone marrow cells in a colony-forming unit assay. Bone marrow mononuclear cells were isolated and cultured in a commercial methylcellulose-based medium containing several recombinant human cytokines. Cultures were prepared with and without 100 ng/mL of rbG-CSF. The size and mean number of colonies per plate from culture days 3 to 9 were compared. We concluded that bovine bone marrow colony growth was supported by this culture medium. The addition of rbG-CSF yielded larger and more numerous colonies. There were significantly more colonies on day 3 (P < 0.001), day 4 (P < 0.001), and day 5 (P = 0.03) with rbG-CSF. Both culture media had the highest colony counts on day 5.
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Affiliation(s)
- Sonya L Keller
- Department of Pathobiology, University of Guelph, Guelph, Ontario N1G 2W1.
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50
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Yamashita K, Nakate T, Okimoto K, Ohike A, Tokunaga Y, Ibuki R, Higaki K, Kimura T. Establishment of new preparation method for solid dispersion formulation of tacrolimus. Int J Pharm 2004; 267:79-91. [PMID: 14602386 DOI: 10.1016/j.ijpharm.2003.07.010] [Citation(s) in RCA: 222] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aim of this study was to establish a new preparation method for solid dispersion formulation (SDF) of tacrolimus, a poorly water-soluble drug, without dichloromethane, because no use of dichloromethane is recommended by ICH harmonized tripartite guideline. To select the appropriate carrier, three different SDFs with polyethylene glycol 6000 (PEG 6000), polyvinylpyrrolidone (PVP) and hydroxypropylmethylcellulose (HPMC) were prepared by the conventional solvent method, in which tacrolimus and the carrier were completely dissolved in the mixture of dichloromethane and ethanol. Powder X-ray diffraction (XRD) and differential scanning calorimetry (DSC) patterns indicated that tacrolimus exists in an amorphous state in all three SDFs. The supersaturated dissolution profiles of tacrolimus were observed in all SDFs, and the highest level of supersaturation for tacrolimus was obtained and maintained for 24h from SDF with HPMC. On the other hand, the supersaturated level from SDF with PEG 6000 or PVP decreased rapidly. The in vivo oral absorption study in dogs showed that bioavailability of tacrolimus from SDF with HPMC was remarkably improved compared with the crystalline powder. It was clarified that HPMC is the most appropriate carrier for SDF of tacrolimus. Then, SDF of tacrolimus was prepared by the new method, which allows us to make SDF of tacrolimus by swelling HPMC with ethanol, in which tacrolimus was completely dissolved. This new method does not need dichloromethane. The physicochemical properties of SDF with HPMC prepared by the new method were the same as those of SDF prepared by the conventional solvent method. Furthermore, SDF with HPMC prepared by the new method was still stable after stored at 40 degrees C for 3 months. The pharmacokinetic parameters after oral administration in monkeys showed no significant difference (P>0.01) between SDFs with HPMC prepared by the two methods. In conclusion, we have established the new preparation method for SDF of tacrolimus with HPMC and the new method makes it possible to prepare SDF of tacroliumus without dichloromethane.
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Affiliation(s)
- Kazunari Yamashita
- Fujisawa Pharmaceutical Co., Ltd., Pharmaceutical Science Laboratories, 1-6, Kashima 2-chome, Yodogawa-ku,Osaka, 532-8514, Japan
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