Production Of Wound Dressings Research Articles

Bactericidal Chitosan Derivatives and Their Superabsorbent Blends with ĸ-Carrageenan.

The aim of this work is research dedicated to the search for new bactericidal systems for use in cosmetic formulations, dermocosmetics, or the production of wound dressings. Over the last two decades, chitosan, due to its special biological activity, has become a highly indispensable biopolymer with very wide application possibilities. Reports in the literature on the antibacterial effects of chitosan are very diverse, but our research has shown that they can be successfully improved through chemical modification. Therefore, in this study, results on the synthesis of new chitosan-based Schiff bases, dCsSB-SFD and dCsSB-PCA, are obtained using two aldehydes: sodium 4-formylbenzene-1,3-disulfonate (SFD) and 2-pyridine carboxaldehyde (PCA), respectively. Chitosan derivatives synthesized in this way demonstrate stronger antimicrobial activity. Carrying out the procedure of grafting chitosan with a caproyl chain allowed obtaining compatible blends of chitosan derivatives with κ-carrageenan, which are stable hydrogels with a high swelling coefficient. Furthermore, the covalently bounded poly(ε-caprolactone) (PCL) chain improved the solubility of obtained polymers in organic solvents. In this respect, the Schiff base-containing polymers obtained in this study, with special hydrogel and antimicrobial properties, are very promising materials for potential use as a controlled-release formulation of both hydrophilic and hydrophobic drugs in cosmetic products for skin health.

Synthesis of Polyvinyl Alcohol (PVA)-Gelatin Hydrogel from White Snapper (Lates calcarifer, Bloch) with Gamma Irradiation and Its Characterizations

The application of nuclear technology in the health sector is increasing. One example is the use of irradiation in production of wound dressings. Research activities have been conducted to study whether polyvinyl alcohol (PVA)-gelatin-based hydrogel from white snapper scales can be processed using gamma irradiation into wound dressings. A series of PVA (10 %) solutions containing gelatin in various concentrations (0-4 %) were treated with three freeze-thaw cycles and then irradiated at doses of 10 and 20 kGy. They were subsequently characterized using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM). Gel fraction, water absorption, and percentage of hydrogel water evaporation rate were tested gravimetrically, while the elongation at break and the tensile strength of the hydrogels were tested with a universal testing meter. The evaluation showed that the hydrogel gel fraction decreased with increasing gelatin concentration from 0 % to 4 % for both irradiation doses (10 and 20 kGy). The rising gelatin concentration demonstrated that increasing gamma radiation dose improved the hydrogel's water absorption, evaporation rate, tensile strength, and elongation at break. PVA-gelatin hydrogel with irregular pore structure was observed from SEM test results. The FTIR measurement results confirmed the formation of crosslinks in the hydrogel matrix. The PVA-gelatin hydrogel produced through gamma irradiation could be used for wound dressings.

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

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.

Pilot-study switchable film dressing & elderly skin/patients with chronic wounds: A non-interventional, non-placebo-controlled, national pilot study

Abstract Aim Film dressings were one of the first modern wound-dressing products. During the removal of the dressing skin stress occurs. An essential role is shearing force between skin and wound dressing playing [3]. This problem includes missing elasticity, flexibility and too strong adhesion [3,4]. The present study was initiated to evaluate if the switchable formulation of the adhesive ensures a durable and strong enough adhesion. Illumination of the film dressing with the UV-A lamp irreversibly switches the adhesion from strong to weak and guarantees a painless/comfortable removal of the dressing. Methods The present study evaluated suitability for use as well as user and patient satisfaction during use of the tested film on patients with chronic wounds. The used film dressing consists of a thin film backing with a non‑latex adhesive. Before removal the adhesion is reduced by illuminating the dressing with the UV-A lamp. Results 54 patients were included in the study. At each dressing change, pain level after dressing change was rated lower compared to the pain level before dressing change. Overall, pain level decreased over the study period. Reactions on the wound edge/wound surroundings have not been reported. Discussion The clinicians gave favourable scores for the tested film dressing. The overall satisfaction with the product was rated very good. Tolerability such as pain during wearing the dressing and upon removal were given good scores. Skin irritation caused in the use of the film dressing did not occur. Conclusion The switchable function of the adhesive allows the adhesion of the film dressing to the skin to be reduced when illuminated by the supplied UV-A lamp. The results of the present study show that the reduced adhesion upon illumination enables easy and comfortable removal of the dressing.

Pilot-Study Lumina Switchable Post-Op Dressing & Postsurgical Wounds: A Non-interventional, Non-placebo-controlled, National Pilot Study

Dressings applied to primarily closed surgical incisions should be appropriate interactive dressing [13] and demonstrate an ability to protect the wound from contaminants and trauma, manage exudate, and avoid excessive pressure to the incision line. Additionally, they should be flexible, well fixed to the skin on application, skin protective (e.g. reduce the risk of blistering or irritation, not excessively adhesive) and waterproof [14]. Film dressings were one of the first modern wound-dressing products. They are extremely flexible, transparent and adhesive. During the removal of the dressing skin stress occurs. An essential role are shearing and friction forces between skin and wound dressing playing. This problem includes missing elasticity, flexibility and too strong adhesion. A non-interventional, non-placebo-controlled, national pilot study was done to prove a new shearing force reducing technique and dressing. The used post-op dressing consists of a thin film backing with a switchable polyurethane adhesive and non-adhering absorption pad. Before removal the adhesion is reduced by illuminating the dressing with the UV-A lamp. 52 patients at a mean age of 55.79 years (SD±16.22) with a total of 52 wounds were included in the study, all of them finalized the 1-week study period. At baseline, pain was measured with a mean of 3.52 (SD±1.26), during the study period pain decreased to a mean of 2.10 (SD±0.97) (VAS 0=no pain, 10=excruciating pain). Significance was calculated as 0,000 (paired t-test). At each dressing change, pain level after dressing change was rated lower compared to the pain level before dressing change. Overall, pain level decreased over the study period. The removal of the dressing after illumination with the UV-A lamp was rated in mean with 1.79 (2. Visit) and 1.86 (3. Visit) on the 6–point-scale (1=very good – 6=insufficient). Significance was calculated as 0,000 for visit 3 (one sample t-test [test value=3,0]). Reactions on the wound edge/wound surroundings have not been reported. In contrast, a reduction of maceration and redness of the wound edge/wound surrounding was observed. The results confirm that the adhesive ensures a safe and effective occlusion/fixation of the dressing and that the strong adhesion enables dressing to function according to specification. There was no deterioration of the wound situation or an infection in any of the cases. The switchable function of the adhesive allows the adhesion of the post-op dressing to the skin to be reduced when illuminated by the supplied UV-A lamp. The results of the present study show that the reduced adhesion upon illumination enables easy and comfortable removal of the dressing.

The effect of a new wound dressing on wound healing: Biochemical and histopathological evaluation

Electrospinning process has gained importance in the production of wound dressings in recent years. The wound dressings prepared by electrospinning method provide many advantages over conventional wound dressings. The aim of this study was to assess the histological, biochemical, and immunohistochemical evaluation of collagen/doxycycline loaded nanofiber wound dressing in both acute and chronic wound healing. Full-thickness wound model was created on rats and rats were divided in two main groups: normoglycemic (acute) and hyperglycemic (chronic) groups. Each group was divided into three sub groups: not treated (control) group, treated with nanofiber wound dressing group and treated with commercial product group. Wound closure rates were measured. Oxidative events were investigated by biochemical analyses. In addition to histological studies, matrix metalloproteinase, tissue inhibitor of metalloproteinase, vascular endothelial growth factor, basic-fibroblast growth factor, and von Willebrand factor levels were investigated with immunohistochemical studies. According to the biochemical analyses, it was concluded that the nanofiber wound dressing helps to increase antioxidant capacity and decrease lipid peroxidation. Immunohistochemical studies showed that nanofiber wound dressing enhanced angiogenesis and shortened the inflammatory phase. It was concluded that an effective and safe prototype nanofiber wound dressing, which has similar wound healing effect to the commercial product, has been developed to be used in acute or chronic wound treatment.

Alginate and carboxymethyl cellulose in monolayer and bilayer films as wound dressings: Effect of the polymer ratio

AbstractIn this study, we investigated different proportions of alginate and carboxymethyl cellulose (CMC) biopolymers in the formulation of films to act as wound dressings. With the casting method, monolayer and bilayer (BL) films were produced with alginate/CMC proportions (weight percentages) of 0:100 (0A), 25:75 (25A), 50:50 (50A), 75:25 (75A), and 100:0 (100A). Thin, homogeneous, and continuous films were obtained with glycerol and crosslinking with CaCl2. The fluid uptake, film stability, and morphological, mechanical, thermal, and barrier properties were evaluated. A general tendency of the film characteristics was visualized: 50A had intermediary characteristics from both polymers; although the liquid behavior characteristics were improved with increasing CMC content, the mechanical properties worsened. When compared to the monolayer film (50A), the BL film 50A–BL demonstrated a better water vapor transmission rate. In this study, we demonstrated the necessity of varying the polymer concentrations to assist in the production of wound dressings. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46941.

Functional and Therapeutic Indications of Liposuction: Personal Experience and Review of the Literature.

Liposuction is the most common cosmetic surgical procedure worldwide. It has evolved from being designed primarily for body contouring to becoming essential adjunct to various other aesthetic procedures, greatly enhancing their outcome. Despite its hard clear differentiation between an aesthetic and therapeutic indication for some pathologic conditions, liposuction has been increasingly applied to a gamut of disorders as a therapeutic tool or to improve function. In fact, liposuction has ceased to define a specific procedure and became synonymous to a surgical technique or tool same as the surgical knife, laser, electrocautery, suture material, or even wound-dressing products. At present, there seems to be an enormous potential for the application of the basic liposuction technique in ablative and reconstructive surgery outside the realm of purely aesthetic procedures. The present review contemplates the various nonaesthetic applications of liposuction, displaying the enormous potentials of what should be considered a basic surgical technique rather than a specific aesthetic procedure. Implications of this new definition of liposuction should induce third-party public payers and insurance companies to reconsider their remuneration and reimbursement policies.

Development of porous lamellar chitosan‐alginate membranes: Effect of different surfactants on biomaterial properties

AbstractIn this work, porous lamellar chitosan‐alginate membranes were developed without the use of freeze‐drying methods or other vacuum‐based approaches. The effects of two different surfactants, Tween 80 and Pluronic F68, on the properties of the membranes were evaluated, aiming at the production of stable consistent foams with improved polysaccharide dispersion. The membranes prepared with Tween 80 had a tensile strength around 1.5 MPa, elongation at break of 2.1% and liquid uptake from 590 to 1370% in distinct solutions, increasing their thickness in up to 3.9 times when immersed in water. The membranes obtained with Pluronic F68 had a tensile strength of 1.0 MPa, elongation at break of 2.0% and liquid uptake from 774 to 1380%, showing an increase in thickness around 3.2 times after exposure to water. The antimicrobial properties of both membranes were also evaluated, showing that despite being porous, the membranes can provide some protection against bacterial permeation. Therefore, membranes produced with Tween 80 and Pluronic F68 were considered to have high potential for use in the production of wound dressings and scaffolds for tissue engineering. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.