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61.
Six cold-sensitive variants have been isolated from Chinese hamster ovary cells by the BUdR-visible light selection technique. The properties of one of these lines have been studied in detail. This line stops dividing immediately after a shift from 39 degrees C to 33 degrees C though its doubling time at 39 degrees C is only slightly longer than that of wild-type cells. The rates of DNA and protein synthesis are severely reduced at 33 degrees C, but the rate of RNA synthesis is not significantly different from wild-type cells. This line may be defective in protein synthesis, but the results of sedimentation analysis indicate that it probably has normal ribosomal subunit assembly. 相似文献
62.
Mohammed S. Taghour Hazem Elkady Wagdy M. Eldehna Nehal M. El-Deeb Ahmed M. Kenawy Eslam B. Elkaeed Aisha A. Alsfouk Mohamed S. Alesawy Ahmed M. Metwaly Ibrahim. H. Eissa 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1903
A thiazolidine-2,4-dione nucleus was molecularly hybridised with the effective antitumor moieties; 2-oxo-1,2-dihydroquinoline and 2-oxoindoline to obtain new hybrids with potential activity against VEGFR-2. The cytotoxic effects of the synthesised derivatives against Caco-2, HepG-2, and MDA-MB-231 cell lines were investigated. Compound 12a was found to be the most potent candidate against the investigated cell lines with IC50 values of 2, 10, and 40 µM, respectively. Furthermore, the synthesised derivatives were tested in vitro for their VEGFR-2 inhibitory activity showing strong inhibition. Moreover, an in vitro viability study against Vero non-cancerous cell line was investigated and the results reflected a high safety profile of all tested compounds. Compound 12a was further investigated for its apoptotic behaviour by assessing the gene expression of four genes (Bcl2, Bcl-xl, TGF, and Survivin). Molecular dynamic simulations authenticated the high affinity, accurate binding, and perfect dynamics of compound 12a against VEGFR-2. 相似文献
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Mahmudul Hasan Rifat Jamil Ahmed Milad Ahmed Foeaz Ahmed Airin Gulshan Mahmudul Hasan 《PLoS computational biology》2022,18(6)
Accelerated cell death 11 (ACD11) is an autoimmune gene that suppresses pathogen infection in plants by preventing plant cells from becoming infected by any pathogen. This gene is widely known for growth inhibition, premature leaf chlorosis, and defense-related programmed cell death (PCD) in seedlings before flowering in Arabidopsis plant. Specific amino acid changes in the ACD11 protein’s highly conserved domains are linked to autoimmune symptoms including constitutive defensive responses and necrosis without pathogen awareness. The molecular aspect of the aberrant activity of the ACD11 protein is difficult to ascertain. The purpose of our study was to find the most deleterious mutation position in the ACD11 protein and correlate them with their abnormal expression pattern. Using several computational methods, we discovered PCD vulnerable single nucleotide polymorphisms (SNPs) in ACD11. We analysed the RNA-Seq data, identified the detrimental nonsynonymous SNPs (nsSNP), built genetically mutated protein structures and used molecular docking to assess the impact of mutation. Our results demonstrated that the A15T and A39D mutations in the GLTP domain were likely to be extremely detrimental mutations that inhibit the expression of the ACD11 protein domain by destabilizing its composition, as well as disrupt its catalytic effectiveness. When compared to the A15T mutant, the A39D mutant was more likely to destabilize the protein structure. In conclusion, these mutants can aid in the better understanding of the vast pool of PCD susceptibilities connected to ACD11 gene GLTP domain activation. 相似文献
66.
Attached media reactors are used for enhancement of wastewater treatment processes including anaerobic condition. Selection of a suitable biofilm carrier is a compelling method to improve anaerobic digestion systems. This study investigates the performance of four fibrous biofilms installed in batch biogas reactors for treatment of cow manure. BioCords HS1, HS2, LS1, and LS2 are manufactured by Bishop Water Technologies, ON, Canada. Effluents and attached growth media were analyzed after batch experiment; methane production, methane yield, transfer efficiencies, organic and solid removal efficiencies, pH, and attached volatile suspended solid (VSS) were measured; VSS attached to biofilms mainly correlated with the specific surface area of each biofilm. Additionally, SEM (scanning electron microscopy) was used for further understanding of biofilm formation process for BioCords and the dissimilarity in their performance. The results indicated that BioCord LS2 had positive impact on achieving higher methane production and removal efficiencies compared to other support media utilized in batch reactors. It was also demonstrated from the experiment that BioCord LS2 potentially could generate higher methane production than conventional batch bioreactor. 相似文献
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Proper balance between self-renewal and differentiation of lung-specific progenitors is absolutely required for normal lung morphogenesis/regeneration. Therefore, understanding the behavior of lung epithelial stem/progenitor cells could identify innovative solutions for restoring normal lung morphogenesis and/or regeneration. The Notch inhibitor Numb is a key determinant of asymmetric or symmetric cell division and hence cell fate. Yet Numb proximal-distal expression pattern and symmetric versus asymmetric division are uncharacterized during lung epithelial development. Herein, the authors find that the cell fate determinant Numb is highly expressed and asymmetrically distributed at the apical side of distal epithelial progenitors and segregated to one daughter cell in most mitotic cells. Knocking down Numb in MLE15 epithelial cells significantly increased the number of cells expressing the progenitor cell markers Sox9/Id2. Furthermore, cadherin hole analysis revealed that most distal epithelial stem/progenitor cells in embryonic lungs divide asymmetrically; with their cleavage, planes are predicted to bypass the cadherin hole, resulting in asymmetric distribution of the cadherin hole to the daughter cells. These novel findings provide evidence for asymmetric cell division in distal epithelial stem/progenitor cells of embryonic lungs and a framework for future translationally oriented studies in this area. 相似文献
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Eman M. Alissa Suhad M. Bahjri Waqar H. Ahmed Nabeel Al-Ama Gordon A. A. Ferns 《Biological trace element research》2009,131(3):215-228
Chromium deficiency is associated with impaired glucose tolerance (IGT) and dyslipidemia. Hence, the objective of the current
study was to investigate chromium status among Saudi men with and without established cardiovascular disease (CVD) and its
relationship to glucose tolerance, lipid profile and other established CVD risk factors. We measured serum and urine chromium
concentrations, fasted lipid profile, plasma glucose, and serum lipid peroxide in 130 Saudi men with an established history
of myocardial infarction and 130 age-matched controls without established CVD. Patients with established CVD had higher serum
triglycerides (p < 0.05) and plasma glucose (p < 0.0001) and lower serum and urinary chromium concentrations (p < 0.0001) than controls. Serum chromium was inversely correlated with plasma glucose among cases and controls (r = −0.189, p < 0.05 and r = −0.354, p < 0.00001, respectively). Plasma glucose (OR 1.127, CI 1.0–1.269, p < 0.05), serum chromium (OR 0.99, CI 0.985–0.995, p < 0.0001), and urinary chromium (OR 0.988, CI 0.981–0.995, p < 0.001) were independently associated with the presence of established coronary disease applying this model. While chromium
metabolism appears to be altered in individuals with CVD, it is unclear whether chromium supplementation would be effective
in CVD prevention among patients with IGT. This would need to be tested in long-term outcome trials. 相似文献
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Stamatia Bellou Mohammed N. Baeshen Ahmed M. Elazzazy Dimitra Aggeli Fotoon Sayegh George Aggelis 《Biotechnology advances》2014
In the last few years, there has been an intense interest in using microalgal lipids in food, chemical and pharmaceutical industries and cosmetology, while a noteworthy research has been performed focusing on all aspects of microalgal lipid production. This includes basic research on the pathways of solar energy conversion and on lipid biosynthesis and catabolism, and applied research dealing with the various biological and technical bottlenecks of the lipid production process. In here, we review the current knowledge in microalgal lipids with respect to their metabolism and various biotechnological applications, and we discuss potential future perspectives. 相似文献