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101.
Arup Kr. Malakar Debashree Choudhury Binata Halder Prosenjit Paul Arif Uddin Supriyo Chakraborty 《Journal of cellular physiology》2019,234(10):16812-16823
Coronary artery disease (CAD) is one of the major cardiovascular diseases affecting the global human population. This disease has been proved to be the major cause of death in both the developed and developing countries. Lifestyle, environmental factors, and genetic factors pose as risk factors for the development of cardiovascular disease. The prevalence of risk factors among healthy individuals elucidates the probable occurrence of CAD in near future. Genome-wide association studies have suggested the association of chromosome 9p21.3 in the premature onset of CAD. The risk factors of CAD include diabetes mellitus, hypertension, smoking, hyperlipidemia, obesity, homocystinuria, and psychosocial stress. The eradication and management of CAD has been established through extensive studies and trials. Antiplatelet agents, nitrates, β-blockers, calcium antagonists, and ranolazine are some of the few therapeutic agents used for the relief of symptomatic angina associated with CAD. 相似文献
102.
The BRCA1 gene is located on the human chromosome 17q21.31 and plays important role in biological processes. The aminoacyl-tRNA synthetases (AARS) are a family of heterogenous enzymes responsible protein synthesis and whose secondary functions include a role in autoimmune myositis. Our findings reveal that the compositional constraint and the preference of more A/T –ending codons determine the codon usage patterns in BRCA1 gene while more G/C-ending codons influence the codon usage pattern of AARS gene among mammals. The codon usage bias in BRCA1 and AARS genes is low. The codon CGC encoding arginine amino acid and the codon TTA encoding leucine were uniformly distributed in BRCA1 and AARS genes, respectively in mammals including human. Natural selection might have played a major role while mutation pressure might have played a minor role in shaping the codon usage pattern of BRCA1 and AARS genes. 相似文献
103.
104.
Arundhati Ganguly Mahammed Moniruzzaman Susanta kumar Chakraborty Samya Karan 《Biological Rhythm Research》2019,50(4):603-615
A chronological relationship between the annual profiles of oxidative stress markers, the key regulator of stress physiology has been sought in a terrestrial mollusc (Nerita articulata) under natural photothermal conditions. The hemolymph samples were collected at two different times in each month (from January to December) and the same was repeated for two consecutive years throughout an annual cycle. The fluctuations in the concentrations of certain heavy and trace metals (zinc, copper, cadmium, mercury, lead, and nickel) in both soil and hemolymph of Nerita are also estimated accordingly. Therefore, the present study aims to explore the rhythmic responses of oxidative stress marker to assess the impact of different trace and heavy metals on selected mollusc species. We tries to develop a realistic conceptual idea to analyze and predict the effect of changing environmental pollution on the possible shift in the rhythmicity of aforesaid antioxidants in terrestrial mollusc and their adaptive responses to thrive in such environment. Our results indicates that the amplitude of circannual rhythms of all the selected stress markers varied accordingly but the pattern of annual fluctuation is noted to be similar, and correlated with the metal accumulation. Therefore current information might help to frame the adaptive strategies for invertebrate species under similar toxic circumstances. 相似文献
105.
Exfoliation glaucoma (XFG) is the most recognizable form of secondary open-angle glaucoma associated with a high risk of blindness. This disease is characterized by white flaky granular deposits in the anterior chamber that leads to the elevation of intraocular pressure (IOP) and subsequent glaucomatous optic nerve damage. Conventionally, XFG is known to respond poorly to medical therapy, and surgical intervention is the only management option in most cases. Various genetic and nongenetic factors are known to be linked to the development of XFG. Despite decades of research on the genetic factors in exfoliation syndrome (XFS) by study groups and global consortia involving different ethnic populations, the pathogenesis of XFS and the mechanism of onset of glaucoma still remains an unsolved mystery. The key lies in understanding how the function of a gene (or set of genes) is altered by environmental triggers, along with other molecular events that underlie the key disease attributes, namely, oxidative stress and the disruption of the blood–aqueous barrier (BAB). It remains a challenge to evolve a theory encompassing all factions of molecular events occurring independently or parallelly that determine the disease manifestation (phenotype) or the stage of the disease in the eye (or in any tissue) in exfoliation. Our enhanced understanding of the underlying molecular pathophysiology of XFG, beyond the known genes or polymorphisms involved in the disease, will lead to improved diagnosis and management and the ability to recognize how the environment influences these key events that lead to the disease phenotype or disease progression. This review summarizes the recent observations and discoveries of four key factors that may hold the answers to the non-lysyl oxidase-like 1 (LOXL1) mechanisms behind XFG pathogenesis, namely, the epigenetic factor miRNA, disordered autophagy along with the potential involvement of mitochondrial mutations, and a compromised aqueous–blood barrier. 相似文献
106.
107.
Paolo M Triozzi Thomas B Irving Henry W Schmidt Zachary P Keyser Sanhita Chakraborty Kelly Balmant Wendell J Pereira Christopher Dervinis Kirankumar S Mysore Jiangqi Wen Jean-Michel An Matias Kirst Daniel Conde 《Plant physiology》2022,188(1):560
Most legumes can establish a symbiotic association with soil rhizobia that trigger the development of root nodules. These nodules host the rhizobia and allow them to fix nitrogen efficiently. The perception of bacterial lipo-chitooligosaccharides (LCOs) in the epidermis initiates a signaling cascade that allows rhizobial intracellular infection in the root and de-differentiation and activation of cell division that gives rise to the nodule. Thus, nodule organogenesis and rhizobial infection need to be coupled in space and time for successful nodulation. The plant hormone cytokinin (CK) contributes to the coordination of this process, acting as an essential positive regulator of nodule organogenesis. However, the temporal regulation of tissue-specific CK signaling and biosynthesis in response to LCOs or Sinorhizobium meliloti inoculation in Medicago truncatula remains poorly understood. In this study, using a fluorescence-based CK sensor (pTCSn::nls:tGFP), we performed a high-resolution tissue-specific temporal characterization of the sequential activation of CK response during root infection and nodule development in M. truncatula after inoculation with S. meliloti. Loss-of-function mutants of the CK-biosynthetic gene ISOPENTENYLTRANSFERASE 3 (IPT3) showed impairment of nodulation, suggesting that IPT3 is required for nodule development in M. truncatula. Simultaneous live imaging of pIPT3::nls:tdTOMATO and the CK sensor showed that IPT3 induction in the pericycle at the base of nodule primordium contributes to CK biosynthesis, which in turn promotes expression of positive regulators of nodule organogenesis in M. truncatula.Precise spatial and temporal characterization of cytokinin (CK) responses reveals the function of the CK biosynthesis gene ISOPENTENYLTRANSFERASE 3 during nodule development in Medicago truncatula. 相似文献
108.
Chakraborty S Senyuk V Sitailo S Chi Y Nucifora G 《The Journal of biological chemistry》2001,276(48):44936-44943
109.
Type 1 fimbriation and phase switching in a natural Escherichia coli fimB null strain, Nissle 1917
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Escherichia coli Nissle 1917 has been used as a probiotic against intestinal disorders for many decades. It is a good colonizer of the human gut and has been reported to be able to express type 1 fimbriae. Type 1 fimbriae are surface organelles which mediate alpha-D-mannose-sensitive binding to various host cell surfaces. The expression is phase variable, and two tyrosine recombinases, FimB and FimE, mediate the inversion of the fimbrial phase switch. Current evidence suggests that FimB can carry out recombination in both directions, whereas FimE-catalyzed switching is on to off only. We show here that under liquid shaking growth conditions, Nissle 1917 did not express type 1 fimbriae, due to a truncation of the fimB gene by an 1,885-bp insertion element. Despite its fimB null status, Nissle 1917 was still capable of off-to-on switching of the phase switch and expressing type 1 fimbriae when grown under static conditions. This phase switching was not catalyzed by FimE, by truncated FimB, or by information residing within the insertion element. No further copies of fimB seemed to be present on the chromosome of Nissle 1917, suggesting that another tyrosine recombinase in Nissle 1917 is responsible for the low-frequency off-to-on inversion of the phase switch that is strongly favored under static growth conditions. This is the first report documenting the non-FimB- or non-FimE-catalyzed inversion of the fim switch. 相似文献
110.
This paper reports studies of the in vitro production of a virus from Helicoverpa armigera (HaSNPV) and its possible use as a specific Helicoverpa/Heliothis larvicide. Growth kinetics of Helicoverpa zea (H. zea) cells and virus occlusion body yields were compared in three SF900II-based media, namely, SF900II (serum-free), SF900II + 1% serum, or SF900II + 10% serum. Viable cell densities were usually higher in the media supplemented with serum than in the serum-free medium; however, in the serum-free medium, cell diameters were 1.7 times greater (i.e., individual cell volumes were five times larger). Both volumetric production of virus occlusion bodies and production per cell were higher in the serum-free medium than in the media supplemented with serum. However, the infectivity of the occlusion bodies from the serum-free medium was less than that with those from the medium supplemented with 10% serum, when compared in bioassays employing newly hatched larvae. The infectivity of the in vitro produced occlusion bodies was also less than that of in vivo produced occlusion bodies in a commercially available virus product, GemStar. High levels of infection of H. armigera larvae obtained in a preliminary field assessment on preflowering tomatoes using the in vitro produced occlusion bodies indicated the suitability of the in vitro process for biopesticide production. 相似文献