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991.
Javad Tavakkoly-Bazzaz Mahsa M. Amoli Vera Pravica Ramesh Chandrasecaran Andrew J. M. Boulton Bagher Larijani Ian V. Hutchinson 《Molecular biology reports》2010,37(7):3625-3630
Vascular factors beside metabolic problems are involved in both etiopathogenesis of diabetic neuropathy, and more remarkably,
later in “repair” phase, that governs the net balance between neuro-regenerative/degenerative reactions. Regarding ischemic
nature of diabetic neuropathy that highlights necessity of blood vessels re-establishment during tissue healing, VEGF (vascular
endothelial growth factor) has been recently the subject of extensive investigations in diabetic neuropathy (DNU). This growth
factor possesses angiogenic potentials in addition to the hemodynamic functions. The distribution of VEGF gene polymorphisms
at positions −7*C/T, −1001*G/C, −1154*G/A and −2578*C/A were analysed by ARMS–PCR in 248 type 1 diabetic British-Caucasian
subjects (81 DNU+, 167 DNU−). We have found that distribution of a VEGF gene polymorphism at promoter region (−7*C/T) was
significantly different between diabetic subjects with vs. without neuropathy and the allele (C) conferred susceptibility
to DNU (P = 0.02; OR = 1.78, 95% CI 1.0–3.1). The present study indicates that polymorphism of the VEGF gene at position −7*C/T might
be implicated in the pathogenesis of diabetic neuropathy as it may harbour some functional/regulatory potential in VEGF gene
expression. However, this requires further studies in order to better understand its phenotypic impact and to investigate
the prognostic value of this polymorphism in diabetic neuropathy as a chronic complication of diabetes. 相似文献
992.
Jitendra Nath Tiwari Mudiam Mohana Krishna Reddy Devendra Kumar Patel Sudhir Kumar Jain Ramesh Chandra Murthy Natesan Manickam 《World journal of microbiology & biotechnology》2010,26(10):1727-1733
Polycyclic aromatic hydrocarbons (PAHs) are common ubiquitous pollutants existing in nature with high recalcitrance and toxicity.
In this study a bacterium capable of aerobic degradation of high molecular weight PAHs (with special reference to pyrene)
was isolated by selective enrichment culture technique from oil refinery effluent sludge. The isolate was characterized as
Achromobacter xylooxidans by 16S rRNA gene sequence analysis technique. For the first time it is hereby reported a bacterium capable of effectively
degrading pyrene (up to 80%), as evident by reverse phase high performance liquid chromatographic analysis (RP-HPLC). After
incubation of Achromobacter xylooxidans in minimal salt medium (MSM) containing pyrene, at concentration of 200 mg/L, as sole source of carbon and energy, there
was decrease in pyrene concentration concomitant with increase in bacterial cell protein concentration. RP-HPLC analysis revealed
that pyrene was degraded into three metabolites viz. I, II and III. The RP-HPLC eluent fraction were collected from 2.5 to
32.0 min by repeated injection of degraded sample, concentrated and analyzed on gas chromatography mass spectroscopy (GC-MS)
for metabolite identification. The fraction shows 1-hydroxypyrene, 1-hydroxy-6-methoxypyrene and 1,6dimethoxypyrene as metabolic
product of pyrene degradation, on the basis of their m/z values. On contrary to the reported PAH degradation with reference to pyrene by different isolates till date; the efficient
degradation, as evident by RP-HPLC, by this isolate holds a promising potential for planning of bioremediation strategies
of contaminated sites. 相似文献
993.
William J. Moore Jeffrey C. Kern Ramesh Bhat Peter V.N. Bodine Shoichi Fukyama Girija Krishnamurthy Ronald L. Magolda Keith Pitts Barb Stauffer Eugene J. Trybulski 《Bioorganic & medicinal chemistry》2010,18(1):190-201
Piperidinyl diphenylsulfonyl sulfonamides are a novel class of molecules that have inhibitory binding affinity for sFRP-1. As a secreted protein sFRP-1 inhibits the function of the secreted Wnt glycoprotein. Therefore, as inhibitors of sFRP-1 these small molecules facilitate the Wnt/β-catenin canonical signaling pathway. Details of the structure–activity relationships and biological activity of this structural class of compounds will be discussed. 相似文献
994.
Temporal Patterns of Poly(ADP-Ribose) Polymerase Activation in the Cortex Following Experimental Brain Injury in the Rat 总被引:3,自引:0,他引:3
Michelle C. LaPlaca Ramesh Raghupathi Ajay Verma rew A. Pieper Kathryn E. Saatman Solomon H. Snyder Tracy K. McIntosh 《Journal of neurochemistry》1999,73(1):205-213
The activation of poly(ADP-ribose) polymerase, a DNA base excision repair enzyme, is indicative of DNA damage. This enzyme also undergoes site-specific proteolysis during apoptosis. Because both DNA fragmentation and apoptosis are known to occur following experimental brain injury, we investigated the effect of lateral fluid percussion brain injury on poly(ADP-ribose) polymerase activity and cleavage. Male Sprague-Dawley rats (n = 52) were anesthetized, subjected to fluid percussion brain injury of moderate severity (2.5-2.8 atm), and killed at 30 min, 2 h, 6 h, 24 h, 3 days, or 7 days postinjury. Genomic DNA from injured cortex at 24 h, but not at 30 min, was both fragmented and able to stimulate exogenous poly(ADP-ribose) polymerase. Endogenous poly(ADP-ribose) polymerase activity, however, was enhanced in the injured cortex at 30 min but subsequently returned to baseline levels. Slight fragmentation of poly(ADP-ribose) polymerase was detected in the injured cortex in the first 3 days following injury, but significant cleavage was detected at 7 days postinjury. Taken together, these data suggest that poly(ADP-ribose) polymerase-mediated DNA repair is initiated in the acute posttraumatic period but that subsequent poly(ADP-ribose) polymerase activation does not occur, possibly owing to delayed apoptosis-associated proteolysis, which may impair the repair of damaged DNA. 相似文献
995.
Patel Bhoomika Sharma Supriya Nair Nisha Majeed Jaseela Goyal Ramesh K. Dhobi Mahaveer 《Molecular and cellular biochemistry》2021,476(6):2345-2364
Molecular and Cellular Biochemistry - The pandemic of Serious Acute Respiratory Syndrome Corona Virus-2 (SARS-CoV-2) that produces corona virus disease (COVID-19) has challenged the entire mankind... 相似文献
996.
Gurudutta GU Verma YK Singh VK Gupta P Raj HG Sharma RK Chandra R 《FEBS letters》2005,579(17):3503-3507
The sequence of Bcl-2 homology domains, BH1 and BH2, is known to be conserved among anti- and pro-apoptotic members of Bcl-2 family proteins. But structural conservation of these domains with respect to functionally active residues playing role in heterodimerization-mediated regulation of apoptosis has never been elucidated. Here, we have suggested the formation of an active site by structurally conserved residues in BH1 (glycine, arginine) and BH2 (tryptophan) domains of Bcl-2 family members, which also accounts for the functional effect of known mutations in BH1 (G145A, G145E) and BH2 (W188A) domains of Bcl-2. 相似文献
997.
Sowmithra Sowmithra Jain Nishtha Kusum Bhonde Ramesh Datta Indrani 《Cellular and molecular neurobiology》2022,42(4):1167-1188
Cellular and Molecular Neurobiology - Increasing evidence suggests that mesenchymal stem cells(MSCs) have beneficial effects in hypoxic ischemic reperfusion injury, but the underlying mechanisms... 相似文献
998.
Iyyangar Deepika Kureeckal V. Ramesh Indira Kumar Abhishek Singh Rajal Debnath Himanshu Dubey Pawan Shukla Kangayam M. Ponnuvel S. Manthira Moorthy Gangavarapu Subrahmanyam 《Entomologia Experimentalis et Applicata》2024,172(5):372-382
Sericulture, the practice of rearing silkworms for the production of silk, is an essential agro-based industry in several countries. However, silkworms are susceptible to a variety of diseases caused by viruses, bacteria and parasites, which may have a significant negative impact on global silk production. Traditional methods of pathogen identification, such as microscopy and laboratory culturing, have limitations in terms of accuracy and efficiency. The development of molecular techniques for pathogen identification has revolutionised the field of sericulture over the last decade. Genomic DNA and RNA-based molecular techniques allow for the rapid and accurate detection of disease-causing pathogens in silkworms. Molecular diagnosis has several advantages over traditional methods, including increased sensitivity and specificity, shorter turnaround time and the ability to detect pathogens that are difficult to culture or visualise under a microscope. Molecular techniques have been applied to detect several important pathogens of silkworms, including Nosema sp., nucleopolyhedrovirus, cypovirus, iflavirus and bidensovirus. The use of molecular diagnostics in sericulture is immensely important as the demand for high-quality silk increases globally and the assessment of emerging pathogens associated with crop loss is essential. Major advancements in the improvement and application of molecular methods for diagnosing widespread silkworm pathogens are discussed. 相似文献
999.
V. K. Sharma V. Ramesh C. Franzini-Armstrong S-S Sheu 《Journal of bioenergetics and biomembranes》2000,32(1):97-104
Studies with electron microscopy have shown that sarcoplasmic reticulum (SR) andmitochondria locate close to each other in cardiac muscle cells. We investigated the hypothesis thatthis proximity results in a transient exposure of mitochondrial Ca2+ uniporter (CaUP) to highconcentrations of Ca2+ following Ca2+ release from the SR and thus an influx of Ca2+into mitochondria. Single ventricular myocytes of rat were skinned by exposing them to aphysiological solution containing saponin (0.2 mg/ml). Cytosolic Ca2+ concentration ([Ca2+]c)and mitochondrial Ca2+ concentration ([Ca2+]m) were measured with fura-2 and rhod2,respectively. Application of caffeine (10 mM) induced a concomitant increase in[Ca2+]c and [Ca2+]m.Ruthenium red, at concentrations that block CaUP but not SR release, diminished thecaffeine-induced increase in [Ca2+]m but not[Ca2+]c. In the presence of 1 mM BAPTA, a Ca2+ chelator,the caffeine-induced increase in [Ca2+]m was reduced substantially less than [Ca2+]c. Moreover,inhibition of SR Ca2+ pump with two different concentrations of thapsigargin caused anincrease in [Ca2+]m, which was related to the rate of [Ca2+]c increase. Finally, electronmicroscopy showed that sites of junctions between SR and T tubules from which Ca2+ is released,or Ca2+ release units, CRUs, are preferentially located in close proximity to mitochondria.The distance between individual SR Ca2+ release channels (feet or ryanodine receptors) isvery short, ranging between approximately 37 and 270 nm. These results are consistent withthe idea that there is a preferential coupling of Ca2+ transport from SR to mitochondria incardiac muscle cells, because of their structural proximity. 相似文献
1000.
Ray RM Bavaria MN Bhattacharya S Johnson LR 《American journal of physiology. Gastrointestinal and liver physiology》2011,300(6):G988-G997
Integrin binding to the extracellular matrix (ECM) activated Rho GTPases, Src, and focal adhesion kinase in intestinal epithelial cells (IEC)-6. Polyamine depletion inhibited activities of Rac1, RhoA, and Cdc42 and thereby migration. However, constitutively active (CA) Rac1 expression abolished the inhibitory effect of polyamine depletion, indicating that polyamines are involved in a process upstream of Rac1. In the present study, we examined the role of polyamines in the regulation of the guanine nucleotide exchange factor, diffuse B-cell lymphoma (Dbl), for Rho GTPases. Polyamine depletion decreased the level as well as the activation of Dbl protein. Dbl knockdown by siRNA altered cytoskeletal structure and decreased Rac1 activity and migration. Cells expressing CA-Dbl increased migration, Rac1 activity, and proliferation. CA-Dbl restored migration in polyamine-depleted cells by activating RhoA, Rac1, and Cdc42. CA-Dbl caused extensive reorganization of the F-actin cortex into stress fibers. Inhibition of Rac1 by NSC23766 significantly decreased migration of vector-transfected cells and CA-Dbl-transfected cells. However, the inhibition of migration was significantly higher in the vector-transfected cells compared with that seen in the CA-Dbl-transfected cells. Dbl localized in the perinuclear region in polyamine-depleted cells, whereas it localized with the stress fibers in control cells. CA-Dbl localized with stress fibers in both the control and polyamine-depleted cells. These results suggest that polyamines regulate the activation of Dbl, a membrane-proximal process upstream of Rac1. 相似文献