Injectable Chitosan-Methoxy Polyethylene Glycol Hybrid Hydrogel Untangling the Wound Healing Behavior: In Vitro and In Vivo Evaluation.

Wound healing, particularly for difficult-to-treat wounds, presents a serious threat and may lead to complications. Currently available dressings lack mucoadhesion, safety, efficacy, and, most importantly, patient compliance. Herein, we developed a unique, simple, and inexpensive injectable chitosan-methoxy polyethylene glycol (chitosan-mPEG) hybrid hydrogel with tunable physicochemical and mechanical properties for wound healing. The detailed physicochemical and rheological characterization of the chitosan-mPEG hydrogel has revealed chemical interaction between available -NH2 groups of chitosan and -COOH groups of mPEG acid, which, to our perspective, enhanced the mechanical and wound healing properties of hybrid chitosan and mPEG hydrogel compared to solo chitosan or PEG hydrogel. By introducing mPEG, the wound healing ability of hydrogel is synergistically improved due to its antibacterial feature, together with chitosan's innate role in hemostasis and wound closure. The detailed hemostasis and wound closure potential of the chitosan-mPEG hydrogel were investigated in a rat model, which confirmed a significant acceleration in wound healing and ultimately wound closure. In conclusion, the developed chitosan-mPEG hydrogel met all the required specifications and could be developed as a promising material for hemostasis, especially wound management, and as an excellent candidate for wound healing application.

Correlation and Influence of Seasonal Variation of Diet with Gut Microbiota Diversity and Metabolism Profile of Chipmunk.

Tamias Sibiricus is the only member of the genus Tamias, a significant and vigorous seed distributor and vital food for their predators. No information is known about the strict diet, gut microbiota structure, and metabolism profile of chipmunks and how they diversify seasonally. The above factors, as well as flexibility toward seasonal shifts, are critical in defining its growth rates, health, survivorship, and population stability. This study explored the diet, gut microbiota composition, and chipmunk metabolism. Additionally, the influence of different seasons was also investigated by using next-generation sequencing. Results revealed that seasons strongly affected a diet: streptophyte accounted for 37% in spring, which was lower than in summer (34.3%) and autumn (31.4%). Further, Ascomycota was observed at 43.8% in spring, which reduced to 36.6% in summer and the lowest (31.3%) in autumn. Whereas, nematodes showed maximum abundance from spring (15.8%) to summer (20.6%) and autumn (24.1%). These results signify the insectivorous nature of the chipmunk in summer and autumn. While herbivorous and fungivorous nature in spring. The DNA analysis revealed that chipmunk mainly feeds on fungi, including Aspergillus and Penicillium genus. Similar to diet composition, the microbiome also exhibited highly significant dissimilarity (p < 0.001, R = 0.235) between spring/autumn and spring/summer seasons. Proteobacteria (35.45%), Firmicutes (26.7%), and Bacteroidetes (23.59%) were shown to be the better discriminators as they contributed the most to causing differences between seasons. Moreover, PICRUSt showed that the assimilation of nutrients were also varied seasonally. The abundance of carbohydrates, lipids, nucleotides, xenobiotics, energy, terpenoids, and polyketides metabolism was higher in spring than in other seasons. Our study illustrates that seasonal reconstruction in the chipmunk diet has a significant role in shaping temporal variations in gut microbial community structure and metabolism profile.

Integrins in the Immunity of Insects: A Review.

Integrins are a large group of cell-surface proteins that are classified as transmembrane proteins. Integrins are classified into different types based on sequence variations, leading to structural and functional diversity. They are broadly distributed in animals and have a wide range of biological functions such as cell-to-cell communication, intracellular cytoskeleton organization, cellular signaling, immune responses, etc. Integrins are among the most abundant cell surface proteins in insects, exhibiting their indispensability in insect physiology. Because of their critical biological involvement in physiological processes, they appear to be a novel target for designing effective pest control strategies. In the current literature review, we first discuss the discovery and expression responses of integrins against various types of pathogens. Secondly, we examine the specific biological roles of integrins in controlling microbial pathogens, such as phagocytosis, encapsulation, nodulation, immune signaling, and so on. Finally, we describe the possible uses of integrins to control agricultural insect pests.

Adjustable Thermo-Responsive, Cell-Adhesive Tissue Engineering Scaffolds for Cell Stimulation through Periodic Changes in Culture Temperature.

A three-dimensional (3D) scaffold ideally provides hierarchical complexity and imitates the chemistry and mechanical properties of the natural cell environment. Here, we report on a stimuli-responsive photo-cross-linkable resin formulation for the fabrication of scaffolds by continuous digital light processing (cDLP), which allows for the mechano-stimulation of adherent cells. The resin comprises a network-forming trifunctional acrylate ester monomer (trimethylolpropane triacrylate, or TMPTA), N-isopropyl acrylamide (NiPAAm), cationic dimethylaminoethyl acrylate (DMAEA) for enhanced cell interaction, and 4-acryloyl morpholine (AMO) to adjust the phase transition temperature (Ttrans) of the equilibrium swollen cross-polymerized scaffold. With glycofurol as a biocompatible solvent, controlled three-dimensional structures were fabricated and the transition temperatures were adjusted by resin composition. The effects of the thermally induced mechano-stimulation were investigated with mouse fibroblasts (L929) and myoblasts (C2C12) on printed constructs. Periodic changes in the culture temperature stimulated the myoblast proliferation.

Artificial Extracellular Matrices Containing Bioactive Glass Nanoparticles Promote Osteogenic Differentiation in Human Mesenchymal Stem Cells.

The present study analyzes the capacity of collagen (coll)/sulfated glycosaminoglycan (sGAG)-based surface coatings containing bioactive glass nanoparticles (BGN) in promoting the osteogenic differentiation of human mesenchymal stroma cells (hMSC). Physicochemical characteristics of these coatings and their effects on proliferation and osteogenic differentiation of hMSC were investigated. BGN were stably incorporated into the artificial extracellular matrices (aECM). Oscillatory rheology showed predominantly elastic, gel-like properties of the coatings. The complex viscosity increased depending on the GAG component and was further elevated by adding BGN. BGN-containing aECM showed a release of silicon ions as well as an uptake of calcium ions. hMSC were able to proliferate on coll and coll/sGAG coatings, while cellular growth was delayed on aECM containing BGN. However, a stimulating effect of BGN on ALP activity and calcium deposition was shown. Furthermore, a synergistic effect of sGAG and BGN was found for some donors. Our findings demonstrated the promising potential of aECM and BGN combinations in promoting bone regeneration. Still, future work is required to further optimize the BGN/aECM combination for increasing its combined osteogenic effect.

Injectable oligomer-cross-linked gelatine hydrogels via anhydride-amine-conjugation.

Injectable gelatine-based hydrogels are valuable tools for drug and cell delivery due to their extracellular matrix-like properties that can be adjusted by the degree of cross-linking. We have established anhydride-containing oligomers for the cross-linking of gelatine via anhydride-amine-conjugation. So far, this conversion required conditions not compatible with cell encapsulation or in vivo injection. In order to overcome this limitation, we developed an array of quarter-oligomers varying in comonomer composition and contents of reactive anhydride units reactive towards amine groups under physiological conditions. The oligomers were of low molecular weight (Mn < 5 kDa) with a high degree of chemically intact anhydrides. Chemical comonomer composition was determined by 1H-NMR. Dissolutions experiments confirmed improved hydrophilicity of the synthesized oligomers over our established compositions. Injectable formulations are described utilizing cytocompatible concentrations of constituent materials and proton-scavenging base. Degree of cross-linking and stiffness of injectable hydrogels were controlled by composition. The gels hold promise as injectable drug or cell carrier and as bioink.

Formulation, characterization and in vitro evaluation of antifungal activity of Nystatin micro emulsion for topical application.

The current research aims at development and assessment of o/w nystatin microemulsion. The pseudoternary phase diagrams were developed to determine microemulsion existence regions by water titration method. Nystatin was liquefied in the blend of oil phase, surfactant and cosurfactant. Microemulsion was made by deliberate mixing of water and stirring in this blend. The S-mix (surfactant-cosurfactant mixtures) of the ratio 1:2 was found better than 1:1 and 2:1 S-mix ratios. In vitro permeation studies by Franz diffusion cell revealed faster rate of nystatin release from such microemulsion (5.37µg/cm2/h) as compared to nystrin (4.79µg/cm2/h), a commercially available aqueous suspension. Kinetic modeling demonstrated zero order drug release and release mechanism found to be anomalous i.e. superposition of dispersion and swelling controlled drug release. Antifungal activity was performed using well diffusion method in vitro against Candida albicans cultures grown on Sabouraud's dextrose agar. The results also confirmed the high diffusion rate of drug from microemulsion as compared to aqueous suspension. The outcomes of this study propose that topical microemulsion of nystatin provides better antifungal activity as compared to emulsion gels or aqueous suspensions.

Biostatistical Options for Quantitative Diet Analysis.

Sufficient statistics knowledge is crucial for the correct design of a research plan. The elucidations of results are interpretive only if appropriate statistical methods are applied. Statistical strategies are a particular approach to demonstrate complicated information in broad and explicable conclusions. The emergence of biostatistical approaches for diet evaluation has improved the accuracy of diet estimation, and different methodologies of data integration promise to magnify our understanding of ecological communities. The present study aimed to compile multiple statistical methods used for diet analysis. More specifically, the significant analysis used in diet assessment, central expectations, and preferences related to each measure was conceptualized. In addition, the ability of each test to evaluate diversity, richness, differentiation, fluctuation, similarity, and quantification of multiple diet items was summarized. Moreover, different options were proposed for researchers to select the appropriate statistical tests. This study covers a framework, aim, and understanding of the statistical test methods of diet analysis.

Molecular charactarization of wheat advanced lines for leaf rust resistant genes using SSR markers.

A total of fifty seven wheat advanced lines were screened to detect the existence of leaf rust resistant genes (Lr9, Lr13, Lr19, Lr24, Lr26, Lr28, Lr32, Lr34, Lr35, Lr36, Lr37, Lr39 and Lr46) using thirteen SSR markers. Only four markers for Lr13, Lr32, Lr34 and Lr35 produced separate, reproducible bands which indicated the positive linkage of leaf rust resistance with these SSR markers. The highest frequency was observed for Lr32 (100%), as it was detected in all fifty seven lines, followed by Lr34 (89.4%) in 51 lines, Lr35 (87.7%) in 50 lines and Lr13 (31.5%) in 18 lines respectively. All the four resistant genes were identified in fifteen lines which is only 26% of the studied population. These results indicate that there are limited number of variant genes for leaf rust resistance in the studied wheat advanced lines. Therefore, strategies for arraying these genes to lengthen infection resistance are advised to eliminate wheat rust diseases. In addition, more reliable and capable markers are essential to be settled for marker assisted selection of these and other genes.

Serpin-14 negatively regulates prophenoloxidase activation and expression of antimicrobial peptides in Chinese oak silkworm Antheraea pernyi.

Genes encoding proteins of serpins superfamily are widely distributed in invertebrates. In insects, serpins play important roles in regulating immune responses and other physiological processes. Here, we report the cloning and characterization of cDNA of Apserpin-14 from Chinese oak silkworm (Antheraea pernyi). The Apserpin-14 gene contains 1206 bp open reading frame, encoding a predicted 401 amino acid residue protein. We expressed the recombinant Apserpin-14 protein in Escherichia coli and then purified protein was used to prepare rabbit anti-Apserpin-14 polyclonal antibodies. Quantitative real-time PCR analysis revealed that mRNA level of Apserpin-14 was highest in the fat body, whereas, among developmental stages the 5th instar and pupal stage showed greatest expression. Furthermore, Escherichia coli, Beauveria bassiana, Micrococcus luteus and nuclear polyhedrosis virus challenge enhanced Apserpin-14 transcript in both the fat body and hemocyte. Recombinant Apserpin-14 added to hemolymph inhibited spontaneous melanization and suppressed prophenoloxidase activation stimulated by M. luteus, but did not affect phenoloxidase (PO) activity. Injection of recombinant Apserpin-14 protein into A. pernyi larvae significantly reduced the transcript levels of antimicrobial peptides in the fat body, while its depletion by double stranded RNA enhanced their expression. We concluded that Apserpin-14 likely involved in regulation of proPO activation and production of antimicrobial peptides, implying its important role in the innate immune system of A. pernyi.

Availability of antidotes and key emergency drugs in tertiary care hospitals of Punjab and assessment of the knowledge of health care professionals in the management of poisoning cases.

This study was conducted to evaluate the availability of antidotes/key emergency drugs in tertiary care hospitals of the Punjab province, and to assess the knowledge of health care professionals in the stocking and administration of antidotes in the proper management of poisoning cases. Seventeen (n=17) tertiary care hospitals of Punjab Pakistan were selected. Two performas (A and B) were designed for 26 antidotes/key emergency drugs and given to the hospital pharmacists and physicians respectively. It was observed that Activated Charcoal, being the universal antidote was found only in 6 hospitals (41%). Digoxin Immune Fab, Edentate Calcium disodium and Glucagon were not available in emergency department of any hospital and even not included in the formulary of any hospital. About 80% pharmacists were aware of the method of preparation of Activated Charcoal and 85% physicians were familiar with its route of administration. Data showed that tertiary care hospitals of Punjab do not stock antidotes according to national drug policy. Moreover the study strongly suggests the development of health care centers and professional by organizing antidote awareness programs, continuous education and record keeping of poisonous cases and availability of emergency drugs around the clock.

Preparation and in vitro evaluation of Nystatin micro emulsion based gel.

Nystatin is a polyene antimycotic obtained from Streptomyces noursei used in the treatment of topical and transdermal fungal infection. Nystatin is nearly insoluble in water (<0.1) and it is amphoteric in nature. The aim of the present study was to design and develop Nystatin micro emulsion based gel for efficient delivery of drug to the skin by water titration method. The Pseudoternary phase diagrams 1:2, 1:1 and 2:1 were constructed by water titration method. Micro emulsion based gel was prepared by using oleic acid, Tween 20, propylene glycol as an oil phase, surfactant and cosurfactant respectively. Cabopol 940 was used as a gelling agent. In vitro evaluation of micro emulsion based gel was done for pH, Viscosity, spreadability and droplet size. Micro emulsion based gel showed greater antifungal activity against Candida albicansas compared to control formulations. In vitro drug release studies were conducted for micro emulsion based gel and control formulation using Franz diffusion cell. Drug penetration through synthetic skin followed Zero order model as the values for R2 higher in case of zero order equation. The optimized micro emulsion based gel was found to be stable and showed no physical changes when exposed to different temperatures for a period of 4 week. The results indicated that the micro emulsion based gel system studied would be a promising tool for enhancing the percutaneous delivery of Nystatin.