scholarly journals Evaluation of Soft Tissue Regenerative Processes After Subcutaneous Implantation of Silver/ Poly(Vinyl Alcohol) and Novel Silver/Poly(Vinyl Alcohol)/Graphene Hydrogels in an Animal Model

2021 ◽  
Vol 71 (3) ◽  
pp. 285-302
Author(s):  
Tijana Lužajić Božinovski ◽  
Vera Todorović ◽  
Ivan Milošević ◽  
Vladimir Gajdov ◽  
Bogomir Bolka Prokić ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Vinyl Alcohol ◽  
International Standards ◽  
Wound Dressings ◽  
Poly Vinyl Alcohol ◽  
Type Iii Collagen ◽  
Type I ◽  
Subcutaneous Implantation ◽  
Ki 67

Abstract A newly produced biomaterial is necessarily subject of standards, which are performed in vivo on animal models. For the evaluation of soft tissue regenerative possibilities after subcutaneous implantation of biomaterials – silver/poly(vinyl alcohol) (Ag/PVA) and novel silver/poly(vinyl alcohol)/graphene (Ag/PVA/Gr) provided for clinical use, sixteen rats were used, according to the instructions of international standards, ISO 10993-6, 2007. Histological sections were observed 7, 15, 30 and 60 days after grafting. These hydrogels were produced by in situ electrochemical synthesis of silver nanoparticles in the polymer matrices, which enabled obtaining completely safe and biocompatible materials, free from any additional toxic chemical reducing agents. Surgical implantation of hydrogels was done according to the permission of the Ethical Committee of the Faculty of Veterinary Medicine, University of Belgrade. Immunohistochemical (IHC) studies included the assessment of smooth muscle expression actin in blood vessels (α-SMA), the expression of laminin and type I and type III collagen in the skin structures, and, the determination of cell proliferation marker expression (Ki-67) keratinocytes. The results were assessed in a semiquantitative manner. The data were analyzed in the statistical software package IBM SPSS 20. The conclusions indicated that Ag/PVA/Gr might be used as wound dressings to enhance the tissue healing potential and established faster integration and shorter retention in the tissue.

Surface Modified Poly(vinyl alcohol) Nanofiber for the Artificial Corneal Stroma

2007 ◽  
Vol 342-343 ◽  
pp. 209-212 ◽  
Author(s):  
Hisatoshi Kobayashi
Keyword(s):  
Corneal Epithelium ◽  
Vinyl Alcohol ◽  
Type I Collagen ◽  
Corneal Stroma ◽  
Light Transmittance ◽  
Poly Vinyl Alcohol ◽  
Type I ◽  
Nanofiber Sheets

Previously we have found that the immobilization of Type I collagen on the poly(vinyl alcohol)(PVA) hydrogel disc was effective in supporting adhesion and growth of the corneal epithelium and stromal cell in vitro. But the durability of the produced corneal epithelium layer in vivo has some problem. We hypothesized the cell construction force is much stronger than the force of the cell adhesion on the flat modified PVA surfaces. Therefore the improvement of mechanical anchoring force between the substrate and formed corneal cell layer maybe become one of the solving methods. In this study, we prepared the PVA nanofiber mat by using the electrospinning method and the surface modification of the PVA nanofiber was studied to improve the durability of the corneal epithelium layer. The collagen-immobilized PVA nanofiber sheets could support the adhesion and proliferation of rabbit corneal epithelial cells. And the stratified corneal epithelium structure was observed on the PVA nanofiber sheets when the epithelium was co-cultured with rabbit corneal stromal cells. It means that the corneal epithelium was well differentiated on the collagen immobilized PVA nanofiber sheet. The stability of the corneal epithelium layer on the PVA was dramatically improved; the stratified epithelium layer was kept for two weeks after the differentiation introduction, totally after one month. A light transmittance of these materials is not yet enough. Further study to improve the transmission of light, is required.

Electrospun poly(vinyl) alcohol/collagen nanofibrous scaffold hybridized by graphene oxide for accelerated wound healing

2018 ◽  
Vol 41 (8) ◽  
pp. 467-473 ◽  
Author(s):  
Rethinam Senthil ◽  
Robert Berly ◽  
Thimmiah Bhargavi Ram ◽  
Nallathambi Gobi
Keyword(s):  
Wound Healing ◽  
Graphene Oxide ◽  
Vinyl Alcohol ◽  
Collagen Type ◽  
Collagen Type I ◽  
Fish Bone ◽  
Poly Vinyl Alcohol ◽  
Type I

Purpose: In this study, a blend of synthetic polymer (poly(vinyl) alcohol), natural polymer (collagen type I from fish bone), and graphene oxide nanoparticles is used to fabricate a composite nanofibrous scaffold, by electrospinning, for their potential application in accelerated wound healing. Methods: The scaffold was characterized for its physicochemical and mechanical properties. In vitro studies were carried out using human keratinocyte cell line (HaCaT) which proved the biocompatibility of the scaffold. In vivo study using mice model was carried out and the healing pattern was evaluated using histopathological studies. Results: Scaffold prepared from poly(vinyl) alcohol, collagen type I from fish bone, and graphene oxide possessed better physicochemical and mechanical properties. In addition, in vivo and in vitro studies showed its accelerated wound healing properties. Conclusion: The scaffold with required strength and biocompatibility may be tried as a wound dressing material in large animals after getting necessary approval.

scholarly journals In Vivo Investigation of Soft Tissue Response of Novel Silver/Poly(Vinyl Alcohol)/ Graphene and Silver/Poly(Vinyl Alcohol)/Chitosan/Graphene Hydrogels Aimed for Medical Applications – The First Experience

2018 ◽  
Vol 68 (3) ◽  
pp. 321-339 ◽  
Author(s):  
Tijana Lužajić Božinovski ◽  
Danica Marković ◽  
Vera Todorović ◽  
Bogomir Prokić Bolka ◽  
Ivan Milošević ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Vinyl Alcohol ◽  
Subcutaneous Tissue ◽  
Tissue Response ◽  
Surrounding Tissue ◽  
Poly Vinyl Alcohol ◽  
Medical Applications ◽  
Capsule Thickness ◽  
Soft Tissue Response

Abstract In this paper, we have shown for the fi rst time the soft tissue response of novel silver/ poly(vinyl alcohol)/graphene (Ag/PVA/Gr) and silver/poly(vinyl alcohol)/chitosan/ graphene (Ag/PVA/CHI/Gr) nanocomposite hydrogels aimed for medical applications. These novel hydrogels were produced by in situ electrochemical synthesis of silver nanoparticles in the polymer matrices as described in our previously published works. Both Ag/PVA/Gr and Ag/PVA/CHI/Gr, as well as controls Ag/PVA, Ag/PVA/CHI and commercial Suprasorb©hydrogel discs, were implanted in the subcutaneous tissue of rats. Implants with the surrounding tissue were dissected after post-implantation on days 7, 15, 30 and 60, and then processed for histological examination. The tissue irritation index (TIrI) score, according to ISO 10993-6, 2007, as well as the number of leukocytes in the peri-implant zone and connective tissue capsule thickness were examined. The results show that each TIrI score, the leukocyte number around the implanted materials and capsule thickness gradually decreased during the observation period. At the endpoint of follow-up, the Ag/PVA/CHI/Gr implant was surrounded with a thinner capsule, while both the TIrI score and the number of leukocytes of the peri-implant zone were greater compared to the Ag/PVA/Gr implant. Despite the observed differences, we can conclude that our in vivo experiment suggested that both novel hydrogels were biocompatible and suitable for medical use.

Honey-Loaded Egg White/Poly(vinyl alcohol)/Clay Bionanocomposite Hydrogel Wound Dressings: In Vitro and In Vivo Evaluations

2019 ◽  
Vol 28 (1) ◽  
pp. 32-46 ◽  
Author(s):  
Zahra Rafati ◽  
Mohammad Sirousazar ◽  
Zuhair Muhammad Hassan ◽  
Farshad Kheiri
Keyword(s):  
Vinyl Alcohol ◽  
Egg White ◽  
Wound Dressings ◽  
Poly Vinyl Alcohol

scholarly journals Preliminary Characterization of Genipin-Cross-Linked Silk Sericin/Poly(vinyl alcohol) Films as Two-Dimensional Wound Dressings for the Healing of Superficial Wounds

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Tippawan Siritientong ◽  
Juthamas Ratanavaraporn ◽  
Teerapol Srichana ◽  
Pornanong Aramwit
Keyword(s):  
Vinyl Alcohol ◽  
Light Transmission ◽  
Transmission Rate ◽  
Wound Dressings ◽  
Poly Vinyl Alcohol ◽  
Cross Linking ◽  
Two Dimensional ◽  
Silk Sericin ◽  
Superficial Skin

The genipin-cross-linked silk sericin/poly(vinyl alcohol) (PVA) films were developed aiming to be applied as two-dimensional wound dressings for the treatment of superficial wounds. The effects of genipin cross-linking concentration on the physical and biological properties of the films were investigated. The genipin-cross-linked silk sericin/PVA films showed the increased surface density, tensile strength, and percentage of elongation, but decreased percentage of light transmission, water vapor transmission rate, and water swelling, compared to the non-cross-linked films. This explained that the cross-linking bonds between genipin and silk sericin would reduce the mobility of molecular chains within the films, resulting in the more rigid molecular structure. Silk sericin was released from the genipin-cross-linked films in a sustained manner. In addition, either L929 mouse fibroblast or HaCat keratinocyte cells showed high percentage of viability when cultured on the silk sericin/PVA films cross-linked with 0.075 and 0.1% w/v genipin. Thein vivosafety test performed according to ISO 10993-6 confirmed that the genipin-cross-linked silk sericin/PVA films were safe for the medical usages. The efficacy of the films for the treatment of superficial skin wounds will be further investigatedin vivoand clinically. The genipin-cross-linked silk sericin/PVA films would be promising choices of two-dimensional wound dressings for the treatment of superficial wounds.

scholarly journals Fabrication of Hybrid Nanofibers from Biopolymers and Poly (Vinyl Alcohol)/Poly (ε-Caprolactone) for Wound Dressing Applications

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2104
Author(s):  
Sibusiso Alven ◽  
Blessing Atim Aderibigbe
Keyword(s):  
Mechanical Properties ◽  
Wound Healing ◽  
Vinyl Alcohol ◽  
Wound Dressing ◽  
Chronic Wounds ◽  
Cellular Adhesion ◽  
Wound Dressings ◽  
Poly Vinyl Alcohol ◽  
High Porosity ◽  
Hybrid Nanofibers

The management of chronic wounds is challenging. The factors that impede wound healing include malnutrition, diseases (such as diabetes, cancer), and bacterial infection. Most of the presently utilized wound dressing materials suffer from severe limitations, including poor antibacterial and mechanical properties. Wound dressings formulated from the combination of biopolymers and synthetic polymers (i.e., poly (vinyl alcohol) or poly (ε-caprolactone) display interesting properties, including good biocompatibility, improved biodegradation, good mechanical properties and antimicrobial effects, promote tissue regeneration, etc. Formulation of these wound dressings via electrospinning technique is cost-effective, useful for uniform and continuous nanofibers with controllable pore structure, high porosity, excellent swelling capacity, good gaseous exchange, excellent cellular adhesion, and show a good capability to provide moisture and warmth environment for the accelerated wound healing process. Based on the above-mentioned outstanding properties of nanofibers and the unique properties of hybrid wound dressings prepared from poly (vinyl alcohol) and poly (ε-caprolactone), this review reports the in vitro and in vivo outcomes of the reported hybrid nanofibers.

scholarly journals Designing New Antibacterial Wound Dressings: Development of a Dual Layer Cotton Material Coated with Poly(Vinyl Alcohol)_Chitosan Nanofibers Incorporating Agrimonia eupatoria L. Extract

Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 83
Author(s):  
Cláudia Mouro ◽  
Colum P. Dunne ◽  
Isabel C. Gouveia
Keyword(s):  
Composite Material ◽  
Vinyl Alcohol ◽  
Pathogenic Bacteria ◽  
Antimicrobial Agents ◽  
Coating Layer ◽  
Wound Dressings ◽  
Poly Vinyl Alcohol ◽  
Microbial Invasion ◽  
Layer Composite ◽  
Medicinal Plant Extracts

Wounds display particular vulnerability to microbial invasion and infections by pathogenic bacteria. Therefore, to reduce the risk of wound infections, researchers have expended considerable energy on developing advanced therapeutic dressings, such as electrospun membranes containing antimicrobial agents. Among the most used antimicrobial agents, medicinal plant extracts demonstrate considerable potential for clinical use, due primarily to their efficacy allied to relatively low incidence of adverse side-effects. In this context, the present work aimed to develop a unique dual-layer composite material with enhanced antibacterial activity derived from a coating layer of Poly(vinyl alcohol) (PVA) and Chitosan (CS) containing Agrimonia eupatoria L. (AG). This novel material has properties that facilitate it being electrospun above a conventional cotton gauze bandage pre-treated with 2,2,6,6-tetramethylpiperidinyl-1-oxy free radical (TEMPO). The produced dual-layer composite material demonstrated features attractive in production of wound dressings, specifically, wettability, porosity, and swelling capacity. Moreover, antibacterial assays showed that AG-incorporated into PVA_CS’s coating layer could effectively inhibit Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) growth. Equally important, the cytotoxic profile of the dual-layer material in normal human dermal fibroblast (NHDF) cells demonstrated biocompatibility. In summary, these data provide initial confidence that the TEMPO-oxidized cotton/PVA_CS dressing material containing AG extract demonstrates adequate mechanical attributes for use as a wound dressing and represents a promising approach to prevention of bacterial wound contamination.

scholarly journals The Design, Characterization and Antibacterial Activity of Heat and Silver Crosslinked Poly(Vinyl Alcohol) Hydrogel Forming Dressings Containing Silver Nanoparticles

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 96
Author(s):  
John Jackson ◽  
Helen Burt ◽  
Dirk Lange ◽  
In Whang ◽  
Robin Evans ◽  
...  
Keyword(s):  
Silver Nanoparticles ◽  
Antibacterial Activity ◽  
Silver Nitrate ◽  
Vinyl Alcohol ◽  
Unmet Need ◽  
Chemical Characterization ◽  
Wound Dressings ◽  
Poly Vinyl Alcohol ◽  
Burn Wound

The prompt treatment of burn wounds is essential but can be challenging in remote parts of Africa, where burns from open fires are a constant hazard for children and suitable medical care may be far away. Consequently, there is an unmet need for an economical burn wound dressing with a sustained antimicrobial activity that might be manufactured locally at low cost. This study describes and characterizes the novel preparation of a silver nitrate-loaded/poly(vinyl alcohol) (PVA) film. Using controlled heating cycles, films may be crosslinked with in situ silver nanoparticle production using only a low heat oven and little technical expertise. Our research demonstrated that heat-curing of PVA/silver nitrate films converted the silver to nanoparticles. These films swelled in water to form a robust, wound-compatible hydrogel which exhibited controlled release of the antibacterial silver nanoparticles. An optimal formulation was obtained using 5% (w/w) silver nitrate in PVA membrane films that had been heated at 140 °C for 90 min. Physical and chemical characterization of such films was complemented by in vitro studies that confirmed the effective antibacterial activity of the released silver nanoparticles against both gram positive and negative bacteria. Overall, these findings provide economical and simple methods to manufacture stable, hydrogel forming wound dressings that release antibiotic silver over prolonged periods suitable for emergency use in remote locations.

scholarly journals Macrophages, the main marker in biocompatibility evaluation of new hydrogels after subcutaneous implantation in rats

2021 ◽  
pp. 088532822110461
Author(s):  
Tijana Lužajić Božinovski ◽  
Vera Todorović ◽  
Ivan Milošević ◽  
Bogomir Bolka Prokić ◽  
Vladimir Gajdov ◽  
...  
Keyword(s):  
Vinyl Alcohol ◽  
Giant Cells ◽  
Surface Interactions ◽  
Poly Vinyl Alcohol ◽  
Nanocomposite Hydrogels ◽  
Tissue Sections ◽  
Biological Responses ◽  
Statistical Relevance ◽  
Biomaterial Surface

Biocompatibility of materials is one of the most important conditions for their successful application in tissue regeneration and repair. Cell-surface interactions stimulate adhesion and activation of macrophages whose acquaintance can assist in designing novel biomaterials that promote favorable macrophage–biomaterial surface interactions for clinical application. This study is designed to determine the distribution and number of macrophages as a means of biocompatibility evaluation of two newly synthesized materials [silver/poly(vinyl alcohol) (Ag/PVA) and silver/poly(vinyl alcohol)/graphene (Ag/PVA/Gr) nanocomposite hydrogels] in vivo, with approval of the Ethics Committee of the Faculty of Veterinary Medicine, University of Belgrade. Macrophages and giant cells were analyzed in tissue sections stained by routine H&E and immunohistochemical methods (CD68+). Statistical relevance was determined in the statistical software package SPSS 20 (IBM corp). The results of the study in terms of the number of giant cells localized around the implant showed that their number was highest on the seventh postoperative day (p.o.d.) in the group implanted with Ag/PVA hydrogels, and on the 30th p.o.d. in the group implanted with Ag/PVA/Gr. Interestingly, the number of macrophages measured in the capsular and pericapsular space was highest in the group implanted with the commercial Suprasorb© material. The increased macrophage number, registered around the Ag/PVA/Gr implant on 60th p.o.d. indicates that the addition of graphene can, in a specific way, modulate different biological responses of tissues in the process of wound healing, regeneration, and integration.

Type VI collagen induces cardiac myofibroblast differentiation: implications for postinfarction remodeling

2006 ◽  
Vol 290 (1) ◽  
pp. H323-H330 ◽  
Author(s):  
Jennifer E. Naugle ◽  
Erik R. Olson ◽  
Xiaojin Zhang ◽  
Sharon E. Mase ◽  
Charles F. Pilati ◽  
...  
Keyword(s):  
Cardiac Fibrosis ◽  
Type I Collagen ◽  
In Vivo Model ◽  
Type Iii Collagen ◽  
Type I ◽  
Myofibroblast Differentiation ◽  
Type Vi Collagen ◽  
Collagen Substrate ◽  
Type Iii

Cardiac fibroblast (CF) proliferation and differentiation into hypersecretory myofibroblasts can lead to excessive extracellular matrix (ECM) production and cardiac fibrosis. In turn, the ECM produced can potentially activate CFs via distinct feedback mechanisms. To assess how specific ECM components influence CF activation, isolated CFs were plated on specific collagen substrates (type I, III, and VI collagens) before functional assays were carried out. The type VI collagen substrate potently induced myofibroblast differentiation but had little effect on CF proliferation. Conversely, the type I and III collagen substrates did not affect differentiation but caused significant induction of proliferation (type I, 240.7 ± 10.3%, and type III, 271.7 ± 21.8% of basal). Type I collagen activated ERK1/2, whereas type III collagen did not. Treatment of CFs with angiotensin II, a potent mitogen of CFs, enhanced the growth observed on types I and III collagen but not on the type VI collagen substrate. Using an in vivo model of myocardial infarction (MI), we measured changes in type VI collagen expression and myofibroblast differentiation after post-MI remodeling. Concurrent elevations in type VI collagen and myofibroblast content were evident in the infarcted myocardium 20-wk post-MI. Overall, types I and III collagen stimulate CF proliferation, whereas type VI collagen plays a potentially novel role in cardiac remodeling through facilitation of myofibroblast differentiation.

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