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11.
Background and aim
PSCA is a tissue specific tumor suppressor or oncogene which has been found to be associated with several human tumors including gallbladder cancer. It is considered to be involved in the cell-proliferation inhibition and/or cell-death induction activity. Therefore, we aimed to investigate the role of PSCA gene polymorphisms in gallbladder cancer risk in North Indian population.Methodology
A total of 405 gallbladder cancer patients and 247 healthy controls were included in the case–control study for risk prediction. We examined the association of two functional SNPs, rs2294008 and rs2978974 in PSCA gene by genotyping using Taqman allelic discrimination assays. Statistical analysis was done using SPSS software, version 17. Linkage disequilibrium and haplotype analysis was done with the help of SNPstats software. FDR test was used to correct for multiple comparisons.Results
No significant associations of rs2294008 and rs2978974 genetic variants of the PSCA gene were found with GBC risk at allele, genotype or haplotype levels. Stratifying the subjects on the basis of gallstone also did not show any significant result. However, on gender stratification, we found a significant association of Trs2294008-Grs2978974 haplotype with higher risk of GBC in females (FDR Pcorr = 0.021, OR = 1.6). In contrary, Trs2294008-A rs2978974 haplotype conferred significant lower risk in males (FDR Pcorr = 0.013; OR = 0.25).Conclusions
These findings suggest that PSCA genetic variants may have a significant effect on GBC susceptibility in a gender specific manner. 相似文献12.
13.
Sheela Nagarkoti Samreen Sadaf Deepika Awasthi Tulika Chandra Kumaravelu Jagavelu Sachin Kumar 《Free radical research》2019,53(3):281-292
Recent report from this lab has shown role of Rac2 in the translocation of inducible nitric oxide synthase (iNOS) to the phagosomal compartment of polymorphonuclear leukocytes (PMNs) following phagocytosis of beads. This study was undertaken to further assess the status and role of tetrahydrobiopterin (BH4), a redox-sensitive cofactor, L-arginine, and the substrate of nitric oxide synthase (NOS) in sustained nitric oxide (˙NO) production in killing of phagocytosed microbes (Escherichia coli) by human PMNs. Time-dependent study revealed consistent NO and reactive oxygen species (ROS) production in the PMNs following phagocytosis of beads. In addition, levels of L-arginine and BH4 were maintained or increased simultaneously to support the enzymatic activity of NOS in the bead activated PMNs. Moreover, translocation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) subunits along with iNOS was reconfirmed in the isolated phagosomes. We demonstrate that increase in the level of NO was supported by L-arginine and BH4 to kill E. coli, by using PMNs from NOS2?/? mice, human PMNs treated with biopterin inhibitor, N-acetyl serotonin (NAS), or by suspending human PMNs in L-arginine deficient medium. Altogether, this study demonstrates that following phagocytosis, sustained. NO production in the PMNs was well-maintained by redox sensitive cofactor, BH4 and substrate, and L-arginine to enable microbial killing. Further results suggest NO production in the human PMNs, along with ROS and myeloperoxidase (MPO) is important to execute antimicrobial activity. 相似文献
14.
Many bacteria used for biotechnological applications are naturally motile. Their "bio-nanopropeller" driven movement allows searching for better environments in a process called chemotaxis. Since bacteria are extremely small in size compared to the bulk fluid volumes in bioreactors, single cell motility is not considered to influence bioreactor operations. However, with increasing interest in localized fluid flow inside reactors, it is important to ask whether individual motility characteristics of bacteria are important in bioreactor operations. The first step in this direction is to try to correlate single cell measurements with population data of motile bacteria in a bioreactor. Thus, we observed the motility behavior of individual bacterial cells, using video microscopy with 33 ms time resolution, as a function of population growth dynamics of batch cultures in shake flasks. While observing the motility behavior of the most intensively studied bacteria, Escherichia coli, we find that overall bacterial motility decreases with progression of the growth curve. Remarkably, this is due to a decrease in a specific motility behavior called "running". Our results not only have direct implications on biofilm formations, but also provide a new direction in bioprocess design research highlighting the role of individual bacterial cell motility as an important parameter. 相似文献
15.
Ryan SK Shotts LR Hong SK Nehra D Groat CR Armstrong JR McClellan AD 《Developmental neurobiology》2007,67(2):173-188
In larval lamprey, descending brain neurons, which regenerate their axons following spinal cord injury, were isolated and examined in cell culture to identify some of the factors that regulate neurite outgrowth. Focal application of 5 mM or 25 mM L-glutamate to single growth cones inhibited outgrowth of the treated neurite, but other neurites from the same neuron were not inhibited, an effect that has not been well studied for neurons in other systems. Glutamate-induced inhibition of neurite outgrowth was abolished by 10 mM kynurenic acid. Application of high potassium media to growth cones inhibited neurite outgrowth, an effect that was blocked by 2 mM cobalt or 100 microM cadmium, suggesting that calcium influx via voltage-gated channels contributes to glutamate-induced regulation of neurite outgrowth. Application of glutamate to growth cones in the presence of 2 microM omega-conotoxin MVIIC (CTX) still inhibited neurite outgrowth, while CTX blocked high potassium-induced inhibition of neurite outgrowth. Thus, CTX blocked virtually all of the calcium influx resulting from depolarization. To our knowledge, this is the first direct demonstration that calcium influx via ligand-gated ion channels can contribute to regulation of neurite outgrowth. Finally, focal application of glutamate to the cell bodies of descending brain neurons inhibited outgrowth of multiple neurites from the same neuron, and this is the first demonstration that multiple neurites can be regulated in this fashion. Signaling mechanisms involving intracellular calcium, similar to those shown here, may be important for regulating axonal regeneration following spinal cord injury in the lamprey. 相似文献
16.
Goyal D Sahoo DK Sahni G 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,850(1-2):384-391
The downstream processing of recombinant streptokinase (rSK), a protein used for dissolution of blood clots has been investigated employing Escherichia coli inclusion bodies obtained after direct chemical extraction followed by expanded bed adsorption chromatography (EBAC). Streptokinase was over-expressed using high cell density (final OD(600)=40) culture of recombinant E. coli, and an SK protein concentration of 1080 mg l(-1) was achieved. The wet cell pellet after centrifugation was re-suspended in 8M urea containing buffer resulting in direct extraction of almost 97% of cellular proteins into solution. Compared to mechanical disruption using sonication, the direct extraction helped in simultaneous cell lysis and inclusion body (IB) solubilization in a single integrated step. The post-extraction solution containing cell debris and cellular proteins was diluted and directly loaded on to an EBAC column containing Streamline phenyl, without clarification. By passing the solution four times through the column and using 1M NaCl during loading, 82.7% rSK activity could be recovered in the 10mM sodium phosphate buffer used for elution. A 3-fold increase in specific activity of rSK, from 0.18 x 10(5) in cell lysate to 0.53 x 10(5)IU mg(-1) resulted after this step. rSK was further purified to near-homogeneity (specific activity=0.96 x 10(5)IU mg(-1)) by a subsequent ion-exchange step operated in packed bed mode. An overall downstream recovery of 63% rSK was achieved after EBAC and ion exchange chromatography. The paper thus describes the purification of rSK using a three-step regime involving simple, efficient and highly facile steps. 相似文献
17.
Nirmaljeet Kaur Prachi Gupta Vikram Saini Sandeep Sherawat Sanjeev Gupta Anita Dua Vinod Kumar Elisha Injeti Ashwani Mittal 《Journal of cellular physiology》2019,234(5):6194-6208
Skeletal muscle atrophy/wasting is associated with impaired protein metabolism in diverse physiological and pathophysiological conditions. Elevated levels of reactive oxygen species (ROS), disturbed redox status, and weakened antioxidant defense system are the major contributing factors toward atrophy. Regulation of protein metabolism by controlling ROS levels and its associated catabolic pathways may help in treating atrophy and related clinical conditions. Although cinnamaldehyde (CNA) enjoys the established status of antioxidant and its role in ROS management is reported, impact of CNA on skeletal muscle atrophy and related pathways is still unexplored. In the current study, the impact of CNA on C2C12 myotubes and the possible protection of cultured cells from H 2O 2-induced atrophy is examined. Myotubes were treated with H 2O 2 in the presence and absence of CNA and the changes in the antioxidative, proteolytic systems, and mitochondrial functions were scored. Morphological analysis showed significant protective effects of CNA on length, diameter, and nuclei fusion index of myotubes. The evaluation of biochemical markers of atrophy; creatine kinase, lactate dehydrogenase, succinate dehydrogenase along with the study of muscle-specific structural protein (i.e., myosin heavy chain-fast [MHCf] type) showed significant protection of proteins by CNA. CNA pretreatment not only checked the activation of proteolytic systems (ubiquitin-proteasome E3-ligases [MuRF1/Atrogin1]), autophagy [Beclin1/LC3B], cathepsin L, calpain, caspase), but also prevented any alteration in the activities of antioxidative defense enzymes (catalase, glutathione- S-transferase, glutathione-peroxidase, superoxide dismutase, glutathione reductase). The results suggest that CNA protects myotubes from H 2O 2-induced atrophy by inhibiting/resisting the amendments in proteolytic systems and maintains cellular redox-balance. 相似文献
18.
Biological Trace Element Research - Vanadium (V) has not been elucidated as an essential mineral in ruminants, though in lower organisms and rat model, its role is well known as insulin—a... 相似文献
19.
Summary Studies were conducted in 22 non-calcareous soils (India) to evaluate various extractants,viz. (6N HCl, 0.1N HCl, EDTA (NH4)2CO3, EDTA NH4OAc, DTPA+CaCl2 and 1M MgCl2) to find critical levels of soil and plant Zn for green gram (Phaseolus aureus Roxb.). The order of extractability by the different extractants was 6N HCl>0.1N HCl>EDTA (NH4)2CO3<EDTA NH4OAc DTPA+CaCl2>1M MgCl2.
Critical levels of 0.48 ppm DTPA × CaCl2 extractable Zn, 0.80 ppm EDTA NH4OAc extractable Zn, 0.70 ppm EDTA (NH4)2CO3 extractable Zn, and 2.2 ppm 0.1N HCl extractable Zn were estimated for the soils tested. The critical Zn concentration in 6 weeks old plants was found to
be 19 ppm. The 0.1N HCl method gave the best correlation (r=0.588**) between extractable Zn and Bray's per cent yield, while with DTPA+CaCl2, it was slightly low (r=0.542**). The DTPA + CaCl2 method gave significant (r=0.73**) correlation with plant Zn concentration. The 0.1N HCl gave the higher correlation with Zn uptake (r=0.661**) than DTPA (r=0.634**) 6N HCl and 1M MgCl2 method gave nonsignificant positive relationship with Bray's per cent yield. For noncalcareous soils apart from the common
use of DTPA+CaCl2, 0.1N HCl can also be used for predicting soil available Zn. The use of 0.1N HCl would be much cheaper than DTPA and other extractants used in the study. 相似文献
20.
Rishein Gupta Harsh Vardhan Pragya Srivastava Sudha Salhan Aruna Mittal 《Reproductive biology and endocrinology : RB&E》2009,7(1):84-13