Preparation, Characterization and Antibacterial Effect of Chitosan Nanoparticles against Food Spoilage Bacteria

Fresh cut fruits and vegetables spoiled by number of bacterial pathogens. In this experiment the low cost, nontoxic and pollution free chitosan nanoparticles were prepared in the laboratory level, characterized by FTIR, XRD and SEM and confirmed the presence of nanoparticles. Various concentrations of nanoparticles (10µg, 20µg, 50µg, 100µg and 150µg) were prepared and used to investigated the antibacterial activity against one positive (Bacillus sp) and one negative bacteria (pseudomonas sp) respectively. The results showed that zone of inhibition against Bacillus sp and Pseudomonas sp were noted at 50µg, 100µg and 150µg concentrations respectively. These results suggested that chitosan nanoparticles can be used as effective growth inhibitors for food spoilage microorganisms. It is confirmed that this pollution free low cost technology is suitable for arresting food spoilage bacteria effectively. Hence, the present study indicated that the non-toxic chitosan nanoparticles may be considered as a food preservative. Hence this preliminary study which will create further research in this new field

In vivo pretreatment of Eudrilus eugeniae powder attenuates β-adrenoceptor toxicity mediated by isoproterenol in rat model

Abstract The present study was designed to discover the potential cardioprotective function of earthworm powder (EWP) extracted from Eudrilus eugeniae on isoproterenol (ISO)-induced myocardial infarction in male Wistar rats. The rats were divided into four groups, with six rats in each group. Certain rats were pretreated with EWP (200 mg/kg bwt) (Group III), and a myocardial infarction was then induced by subcutaneous injection of ISO (85 mg/kg bwt) (Group II). Oral pretreatment of 200 mg/kg bwt of EWP for 28 days significantly (p > 0.05) improved the blood profile levels, including (a) the lipid profile of total cholesterol (TC), free fatty acids (FFA), and triglycerides (TG); (b) low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), high-density lipoprotein (HDL), and protein; and (c) A/G ratio, glucose and uric acid levels. The electrophoretic pattern of elevated lactose dehydrogenase (LDH) levels was recovered by EWP treatment as evidenced by comparison with ISO-induced rats with cardiac damage. The above results indicate that EWP (200 mg/kg bwt) provides a cardioprotective effect by attenuating the blood profile, lipid profile, biochemical levels, and LDH patterns in rats that experienced an ISO-induced myocardial infarction

Zn2+ cross-linked sodium alginate-g-allylamine-mannose polymeric carrier of rifampicin for macrophage targeting tuberculosis nanotherapy

Our aim was to evaluate the capacity of polymeric nanoparticles (PNPs) to selectively deliver an antituberculosis drug (rifampicin; RF) to alveolar macrophages. Anionic biodegradable copolymer sodium alginate-g-allylamine-mannose (SA-g-AA-M) was synthesized by atom transfer free radical polymerization and direct coupling of the respective conjugates. The fabrication of RF-loaded Zn2+ ion-cross-linked SA-g-AA-M PNPs was conducted by an O/W emulsion method followed by ionotropic gelation. The structural nature of the RF-loaded SA-g-AA-M PNPs was analyzed by Fourier transform infrared (FT-IR) spectroscopy. Meanwhile, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to illustrate the shape and morphology of the nanoparticles. The PNPs were observed as uniform spheres in the nanometer range (<300 nm), with a low polydispersity index, and excellent performance in terms of drug encapsulation and release ability. The PNPs also showed strong antimicrobial activities against Mycobacterium tuberculosis. Cytotoxicity evaluation in VERO cells by an MTT assay suggested that the PNPs have good biocompatibility. Alveolar macrophage targeting was evaluated via cellular uptake by A549 cells. The cellular uptake results revealed that the Zn2+ concentration of the PNPs increases the intracellular concentration of RF and enhances its antitubercular efficiency. Overall, the results suggest that PNPs could lead to the development of a possible mannose-containing carrier for a macrophage-targeting drug delivery system

Overcoming the challenge of transduction of human T-cells with chimeric antigen receptor (CAR) specific for ERBB2 antigen

Breast cancer is one of the most common malignancies among woman. Decades of scientific study have linked the overexpression of ERBB2 antigen to aggressive tumors. To target aggressive breast cancer, chimeric antigen receptor (CAR) technology can be utilized. For this, human T-cells are transduced with a gene sequence encoding a CAR that is specific for tumor-associated antigens (TAAs). These genetically-engineered CAR transduced T-cells (CAR-T cells) are able to target the tumor antigen without the need for major histocompatibility complex (MHC) recognition, rendering it a potentially universal immunotherapeutic option. However, efficient transduction of therapeutic gene into human T-cells and further cell expansion are challenging. In this study, we reported a successful optimization of a transduction protocol using spinoculation on CD3+ T-cells with different concentrations of lentiviral plasmid encoding the CAR gene. CD3+T-cells were isolated from the peripheral blood mononuclear cells (PBMCs). The constructed CAR gene was inserted into a lentiviral plasmid containing the green fluorescent protein (GFP) tag and lentiviral particles were produced. These lentiviral particles were used to transduce activated T-cells by spinoculation. T-cells were activated using Dynabead-conjugated CD3/CD28 human T-cell activator and interleukin-2 (IL-2) before transduction. CD3+ T-cells were selected and GFP expression, which indicated transduction, was observed. Future studies will focus on in vitro and in vivo models to determine the efficiency of CAR-T cells in specifically targeting ERBB2-expressing cells

Overcoming the challenge of transduction of human T-cells with chimeric antigen receptor (CAR) specific for ERBB2 antigen

Breast cancer is one of the most common malignancies among woman. Decades of scientific study have linked the overexpression of ERBB2 antigen to aggressive tumors. To target aggressive breast cancer, chimeric antigen receptor (CAR) technology can be utilized. For this, human T-cells are transduced with a gene sequence encoding a CAR that is specific for tumor-associated antigens (TAAs). These genetically-engineered CAR transduced T-cells (CAR-T cells) are able to target the tumor antigen without the need for major histocompatibility complex (MHC) recognition, rendering it a potentially universal immunotherapeutic option. However, efficient transduction of therapeutic gene into human T-cells and further cell expansion are challenging. In this study, we reported a successful optimization of a transduction protocol using spinoculation on CD3+ T-cells with different concentrations of lentiviral plasmid encoding the CAR gene. CD3+T-cells were isolated from the peripheral blood mononuclear cells (PBMCs). The constructed CAR gene was inserted into a lentiviral plasmid containing the green fluorescent protein (GFP) tag and lentiviral particles were produced. These lentiviral particles were used to transduce activated T-cells by spinoculation. T-cells were activated using Dynabead-conjugated CD3/CD28 human T-cell activator and interleukin-2 (IL-2) before transduction. CD3+ T-cells were selected and GFP expression, which indicated transduction, was observed. Future studies will focus on in vitro and in vivo models to determine the efficiency of CAR-T cells in specifically targeting ERBB2-expressing cells

External stimulus-responsive biomaterials designed for the culture and differentiation of ES, iPS, and adult stem cells

The physical and chemical characteristics of biomaterial surface and hydrogels can be altered by external stimuli, such as light irradiation, temperature changes, pH shifts, shear stress forces, electrical forces, and the addition of small chemical molecules. Such external stimulus-responsive biomaterials represent promising candidates that have been developed for the culture and differentiation of embryonic stem (ES) cells, induced pluripotent stem (iPS) cells, and adult stem cells. Biomaterials that are designed to respond in a reversible manner to specific external signals can be formed on micropatterned or non-micropatterned surface, in hydrogels, or on microcarriers. Stem cells and the cells differentiated from them into specific tissue lineages can be cultured and/or differentiated on dishes with immobilized external stimulus-responsive polymers. Cells can be detached from these dishes without using an enzymatic digestion method or a mechanical method when the appropriate external stimulus is generated on the surface. This review discusses the polymers and polymeric designs employed to produce surface and hydrogels for stem cell culture, differentiation, and/or cell detachment using various external stimuli

The synthesis, characterization and in vivo study of mineral substituted hydroxyapatite for prospective bone tissue rejuvenation applications

Minerals substituted apatite (M-HA) nanoparticles were prepared by the precipitation of minerals and phosphate reactants in choline chloride-Thiourea (ChCl–TU) deep eutectic solvent (DESs) as a facile and green way approach. After preparation of nanoparticles (F-M-HA (F = Fresh solvent)), the DESs was recovered productively and reprocess for the preparation of R-M-HA nanoparticles (R = Recycle solvent).The functional groups, phase, surface texture and the elemental composition of the M-HA nanoparticles were evaluated by advance characterization methods. The physicochemical results of the current work authoritative the successful uses of the novel (ChCl–TU) DESs as eco-friendly recuperate and give the medium for the preparation of M-HA nanoparticles. Moreover, the as-synthesized both M-HA nanoparticles exhibit excellent biocompatibility, consisting of cell co-cultivation and cell adhesion, in vivo according to surgical implantation of Wistar rats

Stem cell therapies for reversing vision loss

Current clinical trials that evaluate human pluripotent stem cell (hPSC)-based therapies predominantly target treating macular degeneration of the eyes because the eye is an isolated tissue that is naturally weakly immunogenic. Here, we discuss current bioengineering approaches and biomaterial usage in combination with stem cell therapy for macular degeneration disease treatment. Retinal pigment epithelium (RPE) differentiated from hPSCs is typically used in most clinical trials for treating patients, whereas bone marrow mononuclear cells (BMNCs) or mesenchymal stem cells (MSCs) are intravitreally transplanted, undifferentiated, into patient eyes. We also discuss reported negative effects of stem cell therapy, such as patients becoming blind following transplantation of adipose-derived stem cells, which are increasingly used by 'stem-cell clinics'

Morphological and genetical changes of endothelial progenitor cells afterin-vitroconversion into photoreceptors

Background Retinal degeneration is a condition ensued by various ocular disorders such as artery occlusion, diabetic retinopathy, retrolental fibroplasia and retinitis pigmentosa which cause abnormal loss of photoreceptor cells and lead to eventual vision impairment. No efficient treatment has yet been found, however, the use of stem cell therapy such as bone marrow and embryonic stem cells has opened a new treatment modality for retinal degenerative diseases. The major goal of this study is to analyze the potential of endothelial progenitor cells derived from bone marrow to differentiate into retinal neural cells for regenerative medicine purposes. Methods In this study, endothelial progenitor cells were induced in-vitro with photoreceptor growth factor (taurine) for 21 days. Subsequently, the morphology and gene expression of CRX and RHO of the photoreceptors-induced EPCs were examined through immunostaining assay. Findings The results indicated that the induced endothelial progenitor cells demonstrated positive gene expression of CRX and RHO. Our findings suggested that EPC cells may have a high advantage in cell replacement therapy for treating eye disease, in addition to other neural diseases, and may be a suitable cell source in regenerative medicine for eye disorders