In vitro and in vivo assays on egg white/polyvinyl alcohol/clay nanocomposite hydrogel wound dressings

The present research aimed to examine the biological properties of chitosan (CS)–polyvinyl alcohol (PVA) scaffolds reinforced with graphene oxide (GO) nanosheets, as wound dressings. The scaffolds were characterized by various techniques. The scanning electron microscopy (SEM) and thermogravimetry analyses (TGAs) were used to investigate distribution of the GO within the polymer. The viscoelastic properties were evaluated by dynamic mechanical thermal analysis (DMTA) to examine the quality of a wound dressing. In vitro and in vivo studies were conducted to assess the biocompatibility of the scaffolds as wound dressing. The cell viability and proliferation results indicated that mouse fibroblast cells (L929) could adhere on the 50CS–50PVA/3 wt% GO scaffold. Herewith, the fabricated CS–PVA–GO nanocomposite scaffolds are suggested as promising biomaterials for skin tissue engineering and wound dressing.

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Cytotoxic and Chemopreventive Effects of Gemin D Against Different Mutagens Using In Vitro and In Vivo Assays

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520616666160906092502 ◽

2017 ◽

Vol 17 (5) ◽

pp. 712-718 ◽

Cited By ~ 2

Author(s):

Cristiene Costa Carneiro ◽

Aroldo Vieira de Moraes-Filho ◽

Amanda Silva Fernandes ◽

Suzana da Costa Santos ◽

Daniela de Melo e Silva ◽

...

Keyword(s):

In Vivo Assays

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Hemostatic wound dressings: Predicting their effects by in vitro tests

Journal of Biomaterials Applications ◽

10.1177/0885328219831095 ◽

2019 ◽

Vol 33 (9) ◽

pp. 1285-1297 ◽

Cited By ~ 2

Author(s):

Cornelia Wiegand ◽

Martin Abel ◽

Uta-Christina Hipler ◽

Peter Elsner ◽

Michael Zieger ◽

...

Keyword(s):

Blood Clot ◽

Wound Dressings ◽

In Vitro Tests ◽

Regenerated Cellulose ◽

Oxidized Regenerated Cellulose ◽

Inflammatory Reactions ◽

In Vitro Techniques ◽

Cotton Gauze

Background Application of controlled in vitro techniques can be used as a screening tool for the development of new hemostatic agents allowing quantitative assessment of overall hemostatic potential. Materials and methods Several tests were selected to evaluate the efficacy of cotton gauze, collagen, and oxidized regenerated cellulose for enhancing blood clotting, coagulation, and platelet activation. Results Visual inspection of dressings after blood contact proved the formation of blood clots. Scanning electron microscopy demonstrated the adsorption of blood cells and plasma proteins. Significantly enhanced blood clot formation was observed for collagen together with β-thromboglobulin increase and platelet count reduction. Oxidized regenerated cellulose demonstrated slower clotting rates not yielding any thrombin generation; yet, led to significantly increased thrombin-anti-thrombin-III complex levels compared to the other dressings. As hemostyptica ought to function without triggering any adverse events, induction of hemolysis, instigation of inflammatory reactions, and initiation of the innate complement system were also tested. Here, cotton gauze provoked high PMN elastase and elevated SC5b-9 concentrations. Conclusions A range of tests for desired and undesired effects of materials need to be combined to gain some degree of predictability of the in vivo situation. Collagen-based dressings demonstrated the highest hemostyptic properties with lowest adverse reactions whereas gauze did not induce high coagulation activation but rather activated leukocytes and complement.

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Development of Cephradine-Loaded Gelatin/Polyvinyl Alcohol Electrospun Nanofibers for Effective Diabetic Wound Healing: In-Vitro and In-Vivo Assessments

Pharmaceutics ◽

10.3390/pharmaceutics13030349 ◽

2021 ◽

Vol 13 (3) ◽

pp. 349

Author(s):

Anam Razzaq ◽

Zaheer Ullah Khan ◽

Aasim Saeed ◽

Kiramat Ali Shah ◽

Naveed Ullah Khan ◽

...

Keyword(s):

Wound Healing ◽

Polyvinyl Alcohol ◽

Mtt Assay ◽

Chronic Wound ◽

Drug Loading ◽

Group Identification ◽

Wound Infections ◽

Diabetic Wound

Diabetic wound infections caused by conventional antibiotic-resistant Staphylococcus aureus strains are fast emerging, leading to life-threatening situations (e.g., high costs, morbidity, and mortality) associated with delayed healing and chronic inflammation. Electrospinning is one of the most widely used techniques for the fabrication of nanofibers (NFs), induced by a high voltage applied to a drug-loaded polymer solution. Particular attention is given to electrospun NFs for pharmaceutical applications (e.g., original drug delivery systems) and tissue regeneration (e.g., as tissue scaffolds). However, there is a paucity of reports related to their application in diabetic wound infections. Therefore, we prepared eco-friendly, biodegradable, low-immunogenic, and biocompatible gelatin (GEL)/polyvinyl alcohol (PVA) electrospun NFs (BNFs), in which we loaded the broad-spectrum antibiotic cephradine (Ceph). The resulting drug-loaded NFs (LNFs) were characterized physically using ultraviolet-visible (UV-Vis) spectrophotometry (for drug loading capacity (LC), drug encapsulation efficiency (EE), and drug release kinetics determination), thermogravimetric analysis (TGA) (for thermostability evaluation), scanning electron microscopy (SEM) (for surface morphology analysis), and Fourier-transform infrared spectroscopy (FTIR) (for functional group identification). LNFs were further characterized biologically by in-vitro assessment of their potency against S. aureus clinical strains (N = 16) using the Kirby–Bauer test and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, by ex-vivo assessment to evaluate their cytotoxicity against primary human epidermal keratinocytes using MTT assay, and by in-vivo assessment to estimate their diabetic chronic wound-healing efficiency using NcZ10 diabetic/obese mice (N = 18). Thin and uniform NFs with a smooth surface and standard size (<400 nm) were observed by SEM at the optimized 5:5 (GEL:PVA) volumetric ratio. FTIR analyses confirmed the drug loading into BNFs. Compared to free Ceph, LNFs were significantly more thermostable and exhibited sustained/controlled Ceph release. LNFs also exerted a significantly stronger antibacterial activity both in-vitro and in-vivo. LNFs were significantly safer and more efficient for bacterial clearance-induced faster chronic wound healing. LNF-based therapy could be employed as a valuable dressing material to heal S. aureus-induced chronic wounds in diabetic subjects.

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Cork Oak Endophytic Fungi as Potential Biocontrol Agents against Biscogniauxia mediterranea and Diplodia corticola

Journal of Fungi ◽

10.3390/jof6040287 ◽

2020 ◽

Vol 6 (4) ◽

pp. 287

Author(s):

Daniela Costa ◽

Rui M. Tavares ◽

Paula Baptista ◽

Teresa Lino-Neto

Keyword(s):

Fungal Endophytes ◽

Cork Oak ◽

In Vivo Assays ◽

Oak Trees ◽

Treatment Measures ◽

Dual Plate ◽

Antagonistic Potential ◽

Selection Of

An increase in cork oak diseases caused by Biscogniauxia mediterranea and Diplodia corticola has been reported in the last decade. Due to the high socio-economic and ecologic importance of this plant species in the Mediterranean Basin, the search for preventive or treatment measures to control these diseases is an urgent need. Fungal endophytes were recovered from cork oak trees with different disease severity levels, using culture-dependent methods. The results showed a higher number of potential pathogens than beneficial fungi such as cork oak endophytes, even in healthy plants. The antagonist potential of a selection of eight cork oak fungal endophytes was tested against B. mediterranea and D. corticola by dual-plate assays. The tested endophytes were more efficient in inhibiting D. corticola than B. mediterranea growth, but Simplicillium aogashimaense, Fimetariella rabenhorstii, Chaetomium sp. and Alternaria alternata revealed a high potential to inhibit the growth of both. Simplicillium aogashimaense caused macroscopic and microscopic mycelial/hyphal deformations and presented promising results in controlling both phytopathogens’ growth in vitro. The evaluation of the antagonistic potential of non-volatile and volatile compounds also revealed that A. alternata compounds could be further explored for inhibiting both pathogens. These findings provide valuable knowledge that can be further explored in in vivo assays to find a suitable biocontrol agent for these cork oak diseases.

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Let-7a regulates EV secretion and mitochondrial oxidative phosphorylation by targeting SNAP23 in colorectal cancer

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-020-01813-6 ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

You Dong Liu ◽

Xiao Peng Zhuang ◽

Dong Lan Cai ◽

Can Cao ◽

Qi Sheng Gu ◽

...

Keyword(s):

Oxidative Phosphorylation ◽

Metabolic Reprogramming ◽

Luciferase Reporter ◽

Mitochondrial Oxidative Phosphorylation ◽

In Vivo Assays ◽

Reporter Assays ◽

Extracellular Mirna

Abstract Background MicroRNAs (miRNAs) are abundant in tumor-derived extracellular vesicles (EVs) and the functions of extracellular miRNA to recipient cells have been extensively studied with tumorigenesis. However, the role of miRNA in EV secretion from cancer cells remains unknown. Methods qPCR and bioinformatics analysis were applied for determining extracellular let-7a expression from CRC patient serum and cells. Nanosight particle tracking analysis was performed for investigating the effect of let-7a on EV secretion. Luciferase reporter assays was used for identifying targeted genes synaptosome-associated protein 23 (SNAP23). In vitro and in vivo assays were used for exploring the function of let-7a/SNAP23 axis in CRC progression. Bioenergetic assays were performed for investigating the role of let-7a/SNAP23 in cellular metabolic reprogramming. Results let-7a miRNA was elevated in serum EVs from CRC patients and was enriched in CRC cell-derived EVs. We determined that let-7a could suppress EV secretion directly targeting SNAP23. In turn, SNAP23 promotes EV secretion of let-7a to downregulate the intracellular let-7a expression. In addition, we found a novel mechanism of let-7a/SNAP23 axis by regulating mitochondrial oxidative phosphorylation (OXPHOS) through Lin28a/SDHA signaling pathway. Conclusions Let-7a plays an essential role in not only inhibiting EV secretion, but also suppressing OXPHOS through SNAP23, resulting in the suppression of CRC progression, suggesting that let-7a/SNAP23 axis could provide not only effective tumor biomarkers but also novel targets for tumor therapeutic strategies.

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In vitro and in vivo study of carboxymethyl chitosan/polyvinyl alcohol for wound dressing application

Journal of Applied Polymer Science ◽

10.1002/app.51764 ◽

2021 ◽

pp. 51764

Author(s):

Alireza Akbari ◽

Shahram Rabbani ◽

Shiva Irani ◽

Mojgan Zandi ◽

Fereshteh Sharifi ◽

...

Keyword(s):

Polyvinyl Alcohol ◽

Wound Dressing ◽

Carboxymethyl Chitosan ◽

In Vivo Study

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Application of self-healing, swellable and biodegradable polymers for wound treatment

Journal of Wound Care ◽

10.12968/jowc.2021.30.sup9a.iv ◽

2021 ◽

Vol 30 (Sup9a) ◽

pp. IVi-IVx

Author(s):

Chukwuma O Agubata ◽

Mary A Mbah ◽

Paul A Akpa ◽

Godwin Ugwu

Keyword(s):

Wound Healing ◽

Polyvinyl Alcohol ◽

Biodegradable Polymers ◽

Hydroxypropyl Methylcellulose ◽

Composite Films ◽

Self Healing ◽

Moisture Uptake ◽

Folding Endurance

Aim: Self-healing, swellable and biodegradable polymers are vital materials that may facilitate the different stages of wound healing. The aim of this research was to prepare wound healing films using self-healing polyvinyl alcohol (PVA), swellable hydroxypropyl methylcellulose (HPMC), biodegradable polyglycolic acid (PGA) sutures and ciprofloxacin antibiotic for improved treatment outcome. Methods: Films were formulated through aqueous-based mixing of varying amounts of polyvinyl alcohol (10–20% weight/weight (w/w)) and hydroxypropyl methylcellulose (0.5, 1% w/w) with fixed quantities of ciprofloxacin. PGA sutures were placed as grids within the wet mixtures of the polymers and ciprofloxacin, and thereafter products were air dried. The formulated films were evaluated for swelling ratio, breaking elongation, folding endurance, moisture uptake and loss, compatibility and in vitro antibiotic release. Furthermore, in vivo wound healing was studied using excision model and histopathological examinations. Results: Swelling ratios were above 1.0 and the films were minimally stretchable, with folding endurance greater than 500. Films were stable while moisture uptake and loss were observed to be less than 30%. Among the optimised hydrogel batches, those containing 10% w/w PVA and 1% w/w HPMC with no PGA showed the highest drug release of 73%, whereas the batches with higher PGA content showed higher percentage wound size reduction with minimal scar. The completeness of wound healing with batches containing PVA, HPMC, ciprofloxacin and PGA, along with the standard, is evident considering the massive cornification, regeneration of the epithelial front and stratum spinosum. Conclusion: The findings show that polymer-based multifunctional composite films are suitable for use as dressings for improved wound healing.

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