Fabrication and characterization of a novel wound scaffold based on polyurethane added with Channa striatus for wound dressing applications

Abstract

Wound healing is a complex process and it involves restoration of damaged skin tissues. Several wound dressings comprising naturally made substances are constantly investigated to assist wound healing. In this research, a new wound dressing based on polyurethane (PU) supplemented with essence of Channa striatus (CS) fish oil was made by electrospinning. Morphological study depicted the reduction in fiber diameter than PU with the addition of fish oil (0.552?±?0.109?μm for 8:1 v/v% and 0.519?±?0.196?μm 7:2 v/v%) than the pristine PU (0.971?±?0.205?µm). Fourier transform infrared spectroscopy (FTIR) analysis revealed the presence of fish oil in the composite as identified through increasing peak intensity. Fish oil resulted in the hydrophilic behavior (88?±?3 (8:1 v/v) and 70?±?6 (7:2 v/v)) as revealed in the contact angle analysis. Thermal gravimetric analysis (TGA) showed the superior thermal behavior of the wound dressing patch compared to the PU. Atomic force microscopy (AFM) analysis insinuated a decrease in the surface roughness of the pristine polyurethane with the added fish oil. Coagulation assays signified the delay in the blood clotting time portraying its anti-thrombogenic behavior. Hemolytic assay revealed the less toxic nature of the developed nanocomposites with the red blood cells (RBC’s) depicting its safety with blood. Hence, polyurethane nanofibers supplemented with fish oil made them as deserving candidates for wound dressing application.     

Ptychantins from the Liverwort Ptychanthus Striatus

Five new ptychantins, J‐N, along with two known ones, G and I, were isolated from the liverwort Ptychanthus striatus. Their structures were established by NMR spectroscopic analyses.     

乌鳢卵巢发育的组织学研究

对乌鳢卵巢的成熟时间，卵黄发生过程中液泡、油球、卵黄的形成时间及位置等问题进行了研究．结果表明：乌鳢卵黄发生过程中具３种内含物：液泡、油球和卵黄粒．液泡最先从质膜边缘细胞质产生；在初积脂肪时相，油球从核周围开始形成；卵母胞发育到初积卵黄时相时，卵黄粒开始出现在核周围的油球之间．乌鳢产卵期为５～７月份，最小性成熟鱼全长约为３５ｃｍ，体重约为４００ｇ．     

Growth and liver histology of Channa punctatus exposed to a common biofertilizer

Mustard oil cake (MOC) is widely used as biofertilizer in the field of agriculture and aquaculture. Channa punctatus was exposed to 0.42 g.L^?1 sublethal concentration for 4, 7, 14, 21 and 28 days. Due to such exposure, body growth and histological changes in liver were observed. It was revealed that weight, length and breadth of fish were gradually increased with the days of exposure in compare to control fish, whereas, liver showed an increase in sinusoidal space and lipidosis during early days, followed by a recovery from the stress of MOC on the 28th day.     

Striatal Isolated from Cyathus striatus Extracts Induces Apoptosis in Human Pancreatic Cancer Cells

The aim of the present study was to identify the structure of active compounds in Cyathus stratus that previously demonstrated anti-pancreatic cancer activity. The active compounds were purified from a crude extract by a series of RP-18 preparative chromatography using homemade octadecyl silica gel column. HPLC injection of the crude extract revealed a chromatogram with three main peaks with retention times (RT) 15.6, 18.2, and 22.5 min. Each fraction that exhibited promising activity in vitro was further separated using various available chromatographic techniques. The purified compound with the ultimate anti-cancer activity appeared at RT of 15.8 in the HPLC chromatogram with more than 90% purity. The main peak at the mass spectra appeared at m/z = 446.2304 with the calculated molecular formula of C₂₅H₃₄O₇. One- and two-dimensional NMR analyses indicated that the structure of the active molecule (peak 15.8 min in HPLC) was identified as striatal C. Exposure of human pancreatic cancer cells to purified striatal C resulted in induction of apoptosis. Further studies are needed in order to develop a method for the synthesis of striatal in order to use it in clinical studies for treatment of cancer.