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91.
Oxaliplatin resistance in colorectal cancer cells is mediated via activation of ABCG2 to alleviate ER stress induced apoptosis 下载免费PDF全文
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Michaella Velichkova Joe Juan Pavan Kadandale Steve Jean Inês Ribeiro Vignesh Raman Chris Stefan Amy A. Kiger 《The Journal of cell biology》2010,190(3):407-425
Reversible phosphoinositide phosphorylation provides a dynamic membrane code that balances opposing cell functions. However, in vivo regulatory relationships between specific kinases, phosphatases, and phosphoinositide subpools are not clear. We identified myotubularin (mtm), a Drosophila melanogaster MTM1/MTMR2 phosphoinositide phosphatase, as necessary and sufficient for immune cell protrusion formation and recruitment to wounds. Mtm-mediated turnover of endosomal phosphatidylinositol 3-phosphate (PI(3)P) pools generated by both class II and III phosphatidylinositol 3-kinases (Pi3K68D and Vps34, respectively) is needed to down-regulate membrane influx, promote efflux, and maintain endolysosomal homeostasis. Endocytosis, but not endolysosomal size, contributes to cortical remodeling by mtm function. We propose that Mtm-dependent regulation of an endosomal PI(3)P pool has separable consequences for endolysosomal homeostasis and cortical remodeling. Pi3K68D depletion (but not Vps34) rescues protrusion and distribution defects in mtm-deficient immune cells and restores functions in other tissues essential for viability. The broad interactions between mtm and class II Pi3K68D suggest a novel strategy for rebalancing PI(3)P-mediated cell functions in MTM-related human disease. 相似文献
93.
Male sex genes have shown a pattern of rapid interspecies divergence at both the coding and gene expression level. A common
outcome from crosses between closely-related species is hybrid male sterility. Phenotypic and genetic studies in Drosophila sterile hybrid males have shown that spermatogenesis arrest is postmeiotic with few exceptions, and that most misregulated
genes are involved in late stages of spermatogenesis. Comparative studies of gene regulation in sterile hybrids and parental
species have mainly used microarrays providing a whole genome representation of regulatory problems in sterile hybrids. Real-time
PCR studies can reject or reveal differences not observed in microarray assays. Moreover, differences in gene expression between
samples can be dependant on the source of RNA (e.g., whole body vs. tissue). Here we survey expression in D. simulans, D. mauritiana and both intra and interspecies hybrids using a real-time PCR approach for eight genes expressed at the four main stages
of sperm development. We find that all genes show a trend toward under expression in the testes of sterile hybrids relative
to parental species with only the two proliferation genes (bam and bgcn) and the two meiotic class genes (can and sa) showing significant down regulation. The observed pattern of down regulation for the genes tested can not fully explain
hybrid male sterility. We discuss the down regulation of spermatogenesis genes in hybrids between closely-related species
within the contest of rapid divergence experienced by the male genome, hybrid sterility and possible allometric changes due
to subtle testes-specific developmental abnormalities. 相似文献
94.
E. S. Challaraj Emmanuel V. Vignesh B. Anandkumar S. Maruthamuthu 《Indian journal of microbiology》2011,51(4):488-495
Rare earth elements (REEs) are among the common minerals in the Rare earth environment that are very precious and also enhance
soil properties. The aim of this present study is to evaluate the accumulation of REEs by bacterial isolates of rare earth
environment. Morphological and biochemical characterization were done for 37 bacterial isolates and also molecular studies
were carried out using 16S rRNA sequencing method. The assessment of REEs composition in soil samples of Chavara and Manavalakurichi
analyzed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) showed the abundance of Cerium and Neodymium among lanthanides.
The bioaccumulation study of rare earth elements by Bacillus cereus were accomplished employing FT-IR spectrum and ICP-OES analysis. The significant accumulation of rare earth elements especially
Cerium and Neodymium was noticed in Bacillus cereus isolated from rare earth environment. 相似文献
95.
Mitra T Sailakshmi G Gnanamani A Raja ST Thiruselvi T Gowri VM Selvaraj NV Ramesh G Mandal AB 《International journal of biological macromolecules》2011,48(2):276-285
The present study describes preparation and characterization of a thermally stable and biodegradable biopolymer using collagen and a natural polymer, alginic acid (AA). Required concentration of alginic acid and collagen was optimized and the resulting biopolymer was characterized for, degree of cross-linking, mechanical strength, thermal stability, biocompatibility (toxicity) and biodegradability. Results reveal, the degree of cross-linking of alginic acid (at 1.5% concentration) with collagen was calculated as 75%, whereas it was 83% with standard cross-linking agent, glutaraldehyde (at 1.5% concentration). The AA cross-linked biopolymer was stable up to 245°C and Exhibits 5-6-fold increase in mechanical (tensile) strength compared to plain collagen (native) materials. However, glutaraldehyde cross-linked material exhibits comparatively less thermal stability and brittle in nature (low tensile strength). With regard to cell toxicity, no cytotoxicity was observed for AA cross-linked material when tested with mesenchymal cells and found degradable when treated with collagenase enzyme. The nature of bonding pattern and the reason for thermal stability of AA cross-linked collagen biopolymer was discussed in detail with the help of bioinformatics. A supplementary file on efficacy of AACC as a wound dressing material is demonstrated in detail with animal model studies. 相似文献
96.
Suresh Rathinasamy Subhas Somalingappa Karki Shiladitya Bhattacharya Lakshmanan Manikandan Senthilkumar G. Prabakaran Malaya Gupta 《Journal of enzyme inhibition and medicinal chemistry》2013,28(5):501-507
Bis(1,10-phenanthroline/2,2′-bipyridine) ruthenium(II)complexes containing TCP, TTZ OPBI, and BTSC ligands (where, TCP = 1-thiocarbamoyl-3,5-diphenyl-2-pyrazoline,TTZ = 2-(3,5-diphenyl-4,5-dihydropyrazol-1-yl)-4-phenylthiazole, OPBI = 2-hydroxyphenyl benzimidazole and BTSC = benzoin thiosemicarbazone) have been prepared and characterized. The spectral data suggested that the ligands were coordinated with the metal through nitrogen, sulfur and oxygen atoms. The target complexes were tested in vivo for anticancer activity against transplantable murine tumor cell line, Ehrlich's Ascitic Carcinoma (EAC). All these complexes increased the life span of the EAC-bearing mice, decreased their tumor volume and viable ascitic cell count as well as improved Hb, RBC and WBC counts. These results suggest that the Ru(II) complexes exhibit significant antitumor activity in EAC-bearing mice. It was also observed that the ruthenium complexes protected red blood cells from 2,2′-azo-bis(2-methylpropionamidine) dihydrochloride (AAPH)- induced hemolysis. The inhibitory effect was dose-dependent at a concentration of 20–120 μg/ml. 相似文献
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Acute hypoxic preconditioning prevents palmitic acid‐induced cardiomyocyte apoptosis via switching metabolic GLUT4‐glucose pathway back to CD36‐fatty acid dependent 下载免费PDF全文
100.
Nirala Ramchiary Van Dan Nguyen Xiaonan Li Chang Pyo Hong Vignesh Dhandapani Su Ryun Choi Ge Yu Zhong Yun Piao Yong Pyo Lim 《DNA research》2011,18(5):305-320
Genic microsatellite markers, also known as functional markers, are preferred over anonymous markers as they reveal the variation in transcribed genes among individuals. In this study, we developed a total of 707 expressed sequence tag-derived simple sequence repeat markers (EST-SSRs) and used for development of a high-density integrated map using four individual mapping populations of B. rapa. This map contains a total of 1426 markers, consisting of 306 EST-SSRs, 153 intron polymorphic markers, 395 bacterial artificial chromosome-derived SSRs (BAC-SSRs), and 572 public SSRs and other markers covering a total distance of 1245.9 cM of the B. rapa genome. Analysis of allelic diversity in 24 B. rapa germplasm using 234 mapped EST-SSR markers showed amplification of 2 alleles by majority of EST-SSRs, although amplification of alleles ranging from 2 to 8 was found. Transferability analysis of 167 EST-SSRs in 35 species belonging to cultivated and wild brassica relatives showed 42.51% (Sysimprium leteum) to 100% (B. carinata, B. juncea, and B. napus) amplification. Our newly developed EST-SSRs and high-density linkage map based on highly transferable genic markers would facilitate the molecular mapping of quantitative trait loci and the positional cloning of specific genes, in addition to marker-assisted selection and comparative genomic studies of B. rapa with other related species. 相似文献