Fabrication and evaluation of the regenerative effect of a polycaprolactone/chitosan nanofibrous scaffold containing bentonite nanoparticles in a rat model of deep second-degree burn injury.

Objectives: In the present study, we evaluated the effect of a nanofibrous scaffold including polycaprolactone (PCL), chitosan (CHT), and bentonite nanoparticles (Ben-NPS) on wound healing in order to introduce a novel dressing for burn wounds. Materials and Methods: PCL, PCL/CHT, and PCL/CHT/Ben-NPS nanofibrous scaffolds were fabricated by the electrospinning technique. Their structural and physiochemical characteristics were investigated by Fourier-transform infrared spectroscopy (FTIR) analysis, scanning electron microscopy (SEM), tensile strength, water contact angle, as well as, swelling and degradation profiles test. The disc diffusion assay was carried out to investigate the antibacterial potential of the scaffolds. In addition, the cell viability and proliferation ability of human dermal fibroblasts (HDFs) on the scaffolds were assessed using MTT assay as well as SEM imaging. The wound-healing property of the nanofibrous scaffolds was evaluated by histopathological investigations during 3,7, and 14 days in a rat model of burn wounds. Results: SEM showed that all scaffolds had three-dimensional, beadles-integrated structures. Adding Ben-NPS into the PCL/CHT polymeric composite significantly enhanced the mechanical, swelling, and antibacterial properties. HDFs had the most cell viability and proliferation values on the PCL/CHT/Ben-NPS scaffold. Histopathological evaluation in the rat model revealed that dressing animal wounds with the PCL/CHT/Ben-NPS scaffold promotes wound healing. Conclusion: The PCL/CHT/Ben-NPS scaffold has promising regenerative properties for accelerating skin wound healing.

The internal aqueous phase gelation improves the viability of probiotic cells in a double water/oil/water emulsion system.

This research studied the viability of probiotic bacterium Lactobacillus plantarum (L. plantarum) encapsulated in the internal aqueous phase (W 1) of a water-in-oil-in-water (W 1/O/W 2) emulsion system, with the help of gelation and different gelling agents. Additionally, the physicochemical, rheological, and microstructural properties of the fabricated emulsion systems were assessed over time under the effect of W 1 gelation. The average droplet size and zeta potential of the control system and the systems fabricated using gelatin, alginate, tragacanth gum, and carrageenan were 14.7, 12.0, 5.1, 6.4, and 7.3 µm and - 21.1, -34.1, -46.2, -38.3, and -34.7 mV, respectively. The results showed a significant increase in the physical stability of the system and encapsulation efficiency of L. plantarum after the W 1 gelation. The internal phase gelation significantly increased the viability of bacteria against heat and acidic pH, with tragacanth gum being the best gelling agent for increasing the viability of L. plantarum (28.05% and 16.74%, respectively). Apparent viscosity and rheological properties of emulsions were significantly increased after the W 1 gelation, particularly in those jellified with alginate. Overall, L. plantarum encapsulation in W 1/O/W 2 emulsion, followed by the W 1 gelation using tragacanth gum as the gelling agent, could increase both stability and viability of this probiotic bacteria.

Preparation and evaluation of a polycaprolactone/chitosan/propolis fibrous nanocomposite scaffold as a tissue engineering skin substitute.

Introduction: Recently, the application of nanofibrous mats for dressing skin wounds has received great attention. In this study, we aimed to fabricate and characterize an electrospun nanofibrous mat containing polycaprolactone (PCL), chitosan (CTS), and propolis for use as a tissue-engineered skin substitute. Methods: Raw propolis was extracted, and its phenolic and flavonoid contents were measured. The physiochemical and biological properties of the fabricated mats, including PCL, PCL/CTS, and PCL/CTS/Propolis were evaluated by scanning electron microscopy (SEM), atomic force microscopy (AFM), mechanical analysis, swelling and degradation behaviors, contact angle measurement, cell attachment, DAPI staining, and MTT assay. On the other hand, the drug release pattern of propolis from the PCL/CTS/Propolis scaffold was determined. A deep second-degree burn wound model was induced in rats to investigate wound healing using macroscopical and histopathological evaluations. Results: The results revealed that the propolis extract contained high amounts of phenolic and flavonoid compounds. The fabricated scaffold had suitable physicochemical and mechanical properties. Uniform, bead-free, and well-branched fibers were observed in SEM images of mats. AFM analysis indicated that the addition of CTS and propolis to PCL elevated the surface roughness. MTT results revealed that the electrospun PCL/CTS/Propolis mat was biocompatible. The presence of fibroblast cells on the PCL/CTS/Propolis mats was confirmed by DAPI staining and SEM images. Also, propolis was sustainably released from the PCL/CTS/Propolis mat. The animal study revealed that addition of propolis significantly improved wound healing. Conclusion: The nanofibrous PCL/CTS/Propolis mat can be applied as a tissue-engineered skin substitute for healing cutaneous wounds, such as burn wounds.

Stem cells as an ideal carrier for gene therapy: A new approach to the treatment of hepatitis C virus.

BACKGROUND AND AIM: Various chemical drugs have been approved for the treatment of patients with hepatitis C, but most of these treatments are costly, and also have an inadequate response and many side effects. Also, there is no effective vaccine for hepatitis C due to its high genetic diversity. In recent decades, clinical trials have grown dramatically regarding the benefits of stem cell therapy as a modulator of immune system responses and anti-inflammatory drugs. The most promising point in stem cell therapy and similar therapies is that patients with chronic pain and severe injuries are offered drug-free treatment or surgery. In the present study, we examine the various dimensions of the use of stem cells with the approach of gene therapy carriers as a new treatment method in the treatment of Hepatitis C. METHODS: Search terms were including gene carrier, stem cell therapy, gene therapy, liver disorders, hepatitis C virus. At first, 1000 article titles related to the mentioned keywords for different diseases were found. After removing duplicate titles and items that did not match the scope of the research, articles that met the criteria for entering the research and had usable information were selected. All abstracts of selected articles were studied by researchers. In the initial review, articles related to the title were identified and categorized based on the type of challenge. CONCLUSION: Gene therapy, either directly and in vivo or indirectly and in vitro, requires carriers (vectors) to transfer the gene. These carriers are divided into two groups, viral and non-viral. In indirect gene therapy, living cells are isolated from a person's body and genetically modified. Stem cells have the properties to transfer the desired genes to the patient's body, including the ability to proliferate for a long time and differentiate into the tissue cells in which they are located.

Immunogenicity against hepatitis C virus with mesenchymal stem cells of inbreed BALB/c mice sub cloned with HCVcp protein gene.

BACKGROUND AND AIM: Hepatitis C is one of the leading causes of liver disease in the world and despite extensive research, there is still no vaccine against it. Researchers have identified cell-based therapies as an alternative strategy in advanced liver disorders. The aim of this study was to transfer the hepatitis C virus core protein (HCVcp) gene into mesenchymal stem cells and to evaluate its immunogenicity after injection into mice. MATERIALS AND METHODS: The present study had two experimental and animal stages. In the first step, by designing a vector containing the HCVcp gene and transferring it into the mesenchymal stem cell, gene expression and protein production by the mesenchymal stem cell manipulated by PCR and SDS-PAGE were confirmed. In the second stage, by injecting manipulated mesenchymal stem cells into mice, the level of humoral immune stimulation and splenocytes proliferation was assessed by the ELISA commercial kit. RESULTS: According to molecular studies, the expression of HCVcp was confirmed by mesenchymal stem cells. Also, splenocytes proliferation rate (0.316 ± 0.029) and antibody titer (284 ± 47) in mice treated with manipulated mesenchymal stem cells were significantly increased compared to the control group. CONCLUSION: The results of the present study showed that the use of genetically engineered mesenchymal stem cells while maintaining the immunomodulatory properties of these cells can stimulate specific immune system responses against hepatitis C central protein.

Preparation and evaluation of polycaprolactone/chitosan/Jaft biocompatible nanofibers as a burn wound dressing.

Tissue engineering is an emerging method for replacing damaged tissues. In this study, the potential application of electrospun polycaprolactone/chitosan/ the internal layer of oak fruit (Jaft) as skin scaffolds was investigated. A combination of Polycaprolactone (PCL), chitosan (CH), and the internal layer of oak fruit (Jaft) was used to incorporate mechanical properties of synthetic polymers, biological properties of natural polymers, and antibacterial activity of Jaft. Physical and morphological characteristics of prepared scaffolds were investigated using a scanning electron microscope (SEM), mechanical analysis, swelling ratio, and contact angle. Moreover, chemical and biological properties were evaluated by Fourier-transform infrared spectroscopy (FTIR), chromatography, flow cytometry, DAPI staining, MTT assay, and trypan blue exclusion assay. Obtained results demonstrated that the fabricated scaffolds have good mechanical properties. Moreover, the addition of chitosan and Jaft to the PCL scaffolds improved their water absorption capacity as well as surface hydrophilicity. MTT results showed the fabricated nanofibrous scaffolds have adequate cell viability, which is higher than the cell culture plate at each time point of culture. Furthermore, SEM images of cultured scaffolds, trypan blue exclusion assay, and DAPI staining confirmed that fibroblast cells could be well-attached and proliferate on the PCL/CH/Jaft scaffolds. Results have proven that this novel bioactive scaffold has promising mechanical properties, suitable biocompatibility in vitro, and in vivo. Consequently, it could be a promising candidate for skin tissue engineering applications.

Comparison of oncolytic virotherapy and nanotherapy as two new miRNA delivery approaches in lung cancer.

Lung cancer is known as the second leading cause of cancer death. Finding ways to detect early-stage lung cancer can remarkably increase the survival rate. Biomarkers such as microRNAs can be helpful in cancer diagnosis, predicting its prognosis, and patients' chances of survival. Numerous studies have confirmed the correlation between microRNA expression and the likelihood of patients surviving after treatment. Consequently, it is necessary to study the expression profile of microRNAs during and after treatment. Oncolytic virotherapy and nanotherapy are two neoteric methods that use various vectors to deliver microRNAs into cancer cells. Although these treatments have not yet entered into the clinical trials, much progress has been made in this area. Analyzing the expression profile of microRNAs after applying nanotherapy and oncolytic virotherapy can evaluate the effectiveness of these methods. This review refers to the studies conducted about these two approaches. The advantages and disadvantages of these methods in delivery and affecting microRNA expression patterns are discussed below.

The aplication of Pistacia khinjuk extract nanoemulsion in a biopolymeric coating to improve the shelf life extension of sunflower oil.

In the present study, a hydroalcoholic extract of P. khinjuk was obtained by sonication method at 60°C for 50 min. The measurement revealed that the total phenolic content of the extract was 46.0 mg/g. The results showed that the extract has an antioxidant activity of 73.5% and 8.3 (µmol TE/g DW) in DPPH radical scavenging method and FRAP assay, respectively. Also, Balango (Lallemantia royleana) and Fenugreek (Trigonella foenum-graecum) seed gum and their composition (1:1) were used to prepare the nanoemulsion with P. khinjuk extract. The droplet mean size of nanoemulsions was ranged from 310.34 to 354.19 nm. The highest encapsulation efficiency was observed in Balango nanoemulsion. P. khinjuk extract nanoemulsion coating with Balango and TBHQ was added to sunflower oil at 200 and 100 ppm, respectively. During 24-day storage at 60°C, samples were investigated for peroxide, acid, and p-anisidine values at 4-day intervals. The results showed that oils containing nanoemulsion had the highest stability during storage. However, in all samples peroxide, acid and p-anisidine values increased but the rate of oxidation in samples containing both synthetic and natural antioxidants was slower than the control sample.

Antimicrobial resistance pattern, genetic distribution of ESBL genes, biofilm-forming potential, and virulence potential of Pseudomonas aeruginosa isolated from the burn patients in Tehran Hospitals, Iran.

INTRODUCTION: according to the studies performed, researchers considered Pseudomonas aeruginosa (P. aeruginosa) as the major cause of infectious diseases like burn and wound infection that makes it one of the most threatening opportunistic pathogens. The present research aimed at investigating antimicrobial resistance, biofilm-forming abilities, and frequency of the genes contributed to blaVEB-1, blaPER-1, and blaPSE-1 genes and virulence of P. aeruginosa separated from the burn infections in Tehran, Iran. METHODS: we evaluated the resistance of 156 P. aeruginosa isolates to fifteen antimicrobial agents and generation of the ESBL and MBL enzymes phenotypically based on the CLSI instructions. Moreover, the biofilm forming potential has been assayed in a microtitre plate. In addition, PCR has been used to examine the frequency of virulence-and biofilm-related genes. Furthermore, the PCR of blaVEB-1, blaPSE-1, and blaPER-1 genes has been amplified. RESULTS: according to the results, 72.2% of P. aeruginosa isolates have been MDR and 35.6% and 55.5% have been positive for producing MBL and ESBL, respectively. Moreover, 67.8% have been positive for forming biofilms. It has been found that 15.3% isolates are ESBL-positive; from among them 60% belong to the females and 40% belong to the males. In addition, one and two isolates respectively harbored the blaVEB-1and blaPER-1genes. CONCLUSION: the present research outputs indicated the higher frequency of the multi drug resistance and higher percent of the virulence-related genes in the clinical P. aeruginosa isolates in Iran.

Expression of HCA2 Receptors in Femoral Epiphysis and Metaphysis of Rats with Dexamethasone-Induced Osteoporosis.

The present study describes the changes in expression of hydroxy- carboxylic acid receptor 2 (HCA2 receptor) in femoral epiphysis and metaphysis of rats with glucocorticoid-induced osteoporosis (GIO). 16 growing male Sprauge dawley rats were randomly divided into two equal groups consisting of normal control and rats that were rendered osteoporotic by receiving 0.1 mg/kg/day dexamethasone subcutaneously. After 4 weeks, all rats were sacrificed and immediately right and left femoral bones were removed for RT-qPCR and histological examination, respectively. Immunohistochemical parameters using a primary rabbit polyclonal GPR109A antibody in hematoxylin and eosin- counter stained slides were determined. HCA2 receptor expression was evaluated using RT- qPCR. Qualitative and histomorphometric evaluation of slides revealed the establishment of glucocorticoid- induced osteoporosis (GIO) in rats treated with dexamethasone. In immunohistochemical study, dexamethasone administration appreciably reduced receptor density in all evaluated cell types and in total slides as compared to control. mRNA level of HCA2 receptor gene was reduced in dexamethasone- treated group. GIO may be associated with down regulation of HCA2 receptors in proximal femoral bone of rats at mRNA as well as protein level in no- cell type-specific manner, although reduction in protein expression needs to be further confirmed by western blotting.