Cyclobutane pyrimidine dimers (CPDs) are ultraviolet radiation (UV)-induced carcinogenic DNA photoproducts that lead to UV signature mutations in melanoma. Previously, we discovered that, in addition to their incident formation (iCPDs), UV exposure induces melanin chemiexcitation (MeCh), where UV generates peroxynitrite (ONOO), which oxidizes melanin into melanin-carbonyls (MCs) in their excited triplet state. Chronic MeCh and energy transfer by MCs to DNA generates CPDs for several hours after UV exposure ends (dark CPD, dCPDs).
View Article and Find Full Text PDFConstitutively active K-Ras oncogene mutation at G12V changes the proteome of cells and activates macroautophagy for cell advantage. Inhibition of macroautophagy impairs K-Ras mediated tumor progression to a limited extent with increase of spontaneous tumors due to poorly understood mechanisms. Here, we show that inhibition of macroautophagy in K-Ras G12V mouse embryonic fibroblasts (MEFs) hyper activates chaperon mediated autophagy (CMA).
View Article and Find Full Text PDFBiological detergents like sodium deoxycholate, sodium dodecyl sulphate and Triton X-100 impairs the collagenous and non-collagenous proteins, glycosaminoglycans and growth factors. Further, certain chemical and enzymes are responsible for residual cytotoxicity in the decellularized extracellular matrix. The main focus of this study was to explore the decellularization property of soap nut pericarp extract (SPE) for development of decellularized tubular esophageal scaffold.
View Article and Find Full Text PDFThe aim of this study is to develop a novel decellularization method using aqueous extract of soap nut pericarp (SPE) and its evaluation using hematoxylin-eosin staining, scanning electron microscopy, diamidino-2-phenylindol (DAPI) staining, mechanical testing, sodium dodecyl sulfate polyacrylamide gel electrophoresis and DNA quantification. The presently available decellularization agent raises some concerns due to the potential for presence of residual cytotoxic agents in the extracellular matrix. Histological analysis of hematoxylin and eosin and masson's trichrome stained processed aortic samples shows complete decellularization with preservation of extracellular matrix microarchitecture at 120 h.
View Article and Find Full Text PDFUltraviolet rays induce interstrand and intrastrand DNA cross-links, usually thymine-thymine cyclobutane dimer (T-T) and thymine-thymine pyrimidine-pyrimidone (6-4) photoproduct (T (6-4) T). These DNA cross-links, if left unrepaired, increase the risk of these mutation being incorporated in the genetic material (i.e.
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