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91.
The thiol–disulphide exchange regulates the activity of proteins by redox modulation. Many studies to analyze reactive oxygen species (ROS), particularly, hydrogen peroxide (H2O2) induced changes in the gene expression have been reported, but efforts to detect H2O2 modified proteins are comparatively few. Two-dimensional diagonal redox sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) was used to detect polypeptides which undergo thiol–disulphide exchange in Brassica juncea seedlings following H2O2 (10 mM) treatment for 30 min. Eleven redox responsive polypeptides were identified which included cruciferin, NLI [Nuclear LIM (Lin11, Isl-1 & Mec-3 domains)] interacting protein phosphatase, RuBisCO (ribulose-1,5-bisphosphate carboxylase/oxygenase) large subunit, and myrosinase. Redox modulation of RuBisCO large subunit was further confirmed by western blotting. However, the small subunit of RuBisCO was not affected by these redox changes. All redox modulated targets except NLI interacting protein (although it contains two cysteines) showed oxidation sensitive cysteines by in silico analysis. Interestingly, interactome of cruciferin and myrosinase indicated that they may have additional function(s) beside their well-known roles in the seedling development and abiotic stress respectively. Cruciferin showed interactions with stress associated proteins like defensing-like protein 192 and 2-cys peroxiredoxin. Similarly, myrosinase showed interactions with nitrilase and cytochrome p450 which are involved in nitrogen metabolism and/or hormone biosynthesis. This simple procedure can be used to detect major stress mediated redox changes in other plants. 相似文献
92.
93.
Agarwal R Gupta SK Srivastava S Agrawal SS Saxena R 《Indian journal of experimental biology》2008,46(7):541-546
In normotensive rabbits topical application of Daucus carota seed extract at the concentration of 0.3, 0.6 and 1.2% resulted in mean IOP reduction of 19.33. 23.20 and 25.61% respectively from baseline. As no significant difference was observed between the change in IOP in 0.6 and 1.2% extract treated groups, 0.6% concentration was chosen for further evaluation in rabbits with experimentally elevated IOP. In water loaded rabbits, maximum mean IOP reduction with 0.6% extract was 29.39%, which was comparable to pilocarpine. In steroid pretreated rabbits, maximum mean IOP reduction was 30.27% from baseline, which was significantly higher than pilocarpine. The extract showed a comparatively slower onset of action however, the duration of action was comparable to pilocarpine in all the experimental models. 相似文献
94.
Background
Studies of experts'' problem-solving abilities have shown that experts can attend to the deep structure of a problem whereas novices attend to the surface structure. Although this effect has been replicated in many domains, there has been little investigation into such effects in medicine in general or patient management in particular.Methodology/Principal Findings
We designed a 10-item forced-choice triad task in which subjects chose which one of two hypothetical patients best matched a target patient. The target and its potential matches were related in terms of surface features (e.g., two patients of a similar age and gender) and deep features (e.g., two diabetic patients with similar management strategies: a patient with arthritis and a blind patient would both have difficulty with self-injected insulin). We hypothesized that experts would have greater knowledge of management categories and would be more likely to choose deep matches. We contacted 130 novices (medical students), 11 intermediates (medical residents), and 159 experts (practicing endocrinologists) and 15, 11, and 8 subjects (respectively) completed the task. A linear mixed effects model indicated that novices were less likely to make deep matches than experts (t(68) = −3.63, p = .0006), while intermediates did not differ from experts (t(68) = −0.24, p = .81). We also found that the number of years in practice correlated with performance on diagnostic (r = .39, p = .02), but not management triads (r = .17, p = .34).Conclusions
We found that experts were more likely than novices to match patients based on deep features, and that this pattern held for both diagnostic and management triads. Further, management and diagnostic triads were equally salient for expert physicians suggesting that physicians recognize and may create management-oriented categories of patients. 相似文献95.
Metal/metalloid stress tolerance in plants: role of ascorbate,its redox couple,and associated enzymes 总被引:1,自引:0,他引:1
Naser A. Anjum Sarvajeet S. Gill Ritu Gill Mirza Hasanuzzaman Armando C. Duarte Eduarda Pereira Iqbal Ahmad Renu Tuteja Narendra Tuteja 《Protoplasma》2014,251(6):1265-1283
The enhanced generation of reactive oxygen species (ROS) under metal/metalloid stress is most common in plants, and the elevated ROS must be successfully metabolized in order to maintain plant growth, development, and productivity. Ascorbate (AsA) is a highly abundant metabolite and a water-soluble antioxidant, which besides positively influencing various aspects in plants acts also as an enigmatic component of plant defense armory. As a significant component of the ascorbate-glutathione (AsA-GSH) pathway, it performs multiple vital functions in plants including growth and development by either directly or indirectly metabolizing ROS and its products. Enzymes such as monodehydroascorbate reductase (MDHAR, EC 1.6.5.4) and dehydroascorbate reductase (DHAR, EC 1.8.5.1) maintain the reduced form of AsA pool besides metabolically controlling the ratio of AsA with its oxidized form (dehydroascorbate, DHA). Ascorbate peroxidase (APX, EC 1.11.1.11) utilizes the reduced AsA pool as the specific electron donor during ROS metabolism. Thus, AsA, its redox couple (AsA/DHA), and related enzymes (MDHAR, DHAR, and APX) cumulatively form an AsA redox system to efficiently protect plants particularly against potential anomalies caused by ROS and its products. Here we present a critical assessment of the recent research reports available on metal/metalloid-accrued modulation of reduced AsA pool, AsA/DHA redox couple and AsA-related major enzymes, and the cumulative significance of these antioxidant system components in plant metal/metalloid stress tolerance. 相似文献
96.
Oxytocin (OT) is a versatile neuropeptide that is involved in a variety of mammalian behaviors, and its role in reproductive function and behavior has been well established. The majority of pharmacological studies of the effects of OT on male sexual behavior have focused on the paraventricular nucleus (PVN), ventral tegmental area (VTA), hippocampus, and amygdala. Less attention has been given to the medial preoptic area (MPOA), a major integrative site for male sexual behavior. The present study investigated the effects of intra-MPOA administration of OT and (d(CH2)51, Tyr(Me)2, Thr4, Orn8, Tyr-NH29)-vasotocin, an OT antagonist (OTA), on copulation in the male rat. The relationship between OT receptor (OTR) binding levels in the MPOA and sexual efficiency was also explored. Microinjection of OT into the MPOA facilitated copulation in sexually experienced male rats, whereas similar injections of an OTA inhibited certain aspects of copulation but had no significant effect on locomotor activity in an open field. Contrary to expectation, sexually efficient males had lower levels of OTR binding in the rostral MPOA compared to inefficient animals. The present data suggest that OT activity in the MPOA is not necessary for the expression of male sexual behavior but is sufficient to facilitate copulatory behaviors and improve sexual efficiency in sexually experienced male rats. These data also suggest that OTR activity in the MPOA stimulates anogenital investigation, facilitates the initiation of copulation, and plays a role in the sensitization effect of the first ejaculation on subsequent ejaculations. 相似文献
97.
Sikander Pal Choudhary Renu Bhardwaj B. D. Gupta Prabhu Dutt R. K. Gupta Mukesh Kanwar Stefania Biondi 《Acta Physiologiae Plantarum》2011,33(4):1319-1333
The present investigation recorded significant restoration of seedling growth (root length, shoot length and fresh weight)
upon application of 24-epibrassinolide (EBL) and putrescine (Put) to 7-day-old seedlings of Raphanus sativus L. cv. Pusa chetki grown under copper (Cu) ion stress. EBL and Put with/or without Cu ion treated seedlings showed increased
titers of ascorbic acid, total phenols and proline when compared with Cu-stressed seedlings. Differential responses in the
activities of guaiacol peroxidase (GPOX) and catalase (CAT) were noted for EBL and Put alone or with/or without Cu ion treatment.
Decreased activities of glutathione reductase (GR) and superoxide dismutase (SOD) noted for EBL and Put alone were observed
to enhance significantly when applied in combination with Cu ion solution. A remarkable decrease in malondialdehyde contents
was observed in seedlings treated with EBL and Put alone and with/or without Cu ion stress. Enhanced free radical scavenging
activities were also recorded for seedlings given EBL and Put alone or in combination over Cu ion stressed seedlings. Maximum
DPPH activity was observed in seedlings treated with Put and EBL 10−9 M + Put. Significant enhancements in deoxyribose and reducing power activities were too recorded for Put, EBL and Put + 10−9 M EBL treatments. Improved seedling growth, antioxidant levels (ascorbic acid, total phenols and proline) and enzymic (GPOX,
CAT, SOD and GR) activities and free radical scavenging capacities along with reduced membrane damage in seedlings given EBL
and Put with/or without Cu stress suggests significant and positive interactions of EBL and Put in alleviating the Cu ion
induced oxidative damage in radish seedlings. 相似文献
98.
Michael S. Parker Renu Sah Ambikaipakan Balasubramaniam Floyd R. Sallee Edwards A. Park Steven L. Parker 《Amino acids》2014,46(7):1589-1604
While the ribosome constitution is similar in all biota, there is a considerable increase in size of both ribosomal proteins (RPs) and RNAs in eukaryotes as compared to archaea and bacteria. This is pronounced in the large (60S) ribosomal subunit (LSU). In addition to enlargement (apparently maximized already in lower eukarya), the RP changes include increases in fraction, segregation and clustering of basic residues, and decrease in hydrophobicity. The acidic fraction is lower in eukaryote as compared to prokaryote RPs. In all eukaryote groups tested, the LSU RPs have significantly higher content of basic residues and homobasic segments than the SSU RPs. The vertebrate LSU RPs have much higher sequestration of basic residues than those of bacteria, archaea and even of the lower eukarya. The basic clusters are highly aligned in the vertebrate, but less in the lower eukarya, and only within families in archaea and bacteria. Increase in the basicity of RPs, besides helping transport to the nucleus, should promote stability of the assembled ribosome as well as the association with translocons and other intracellular matrix proteins. The size and GC nucleotide bias of the expansion segments of large LSU rRNAs also culminate in the vertebrate, and should support ribosome association with the endoplasmic reticulum and other intracellular networks. However, the expansion and nucleotide bias of eukaryote LSU rRNAs do not clearly correlate with changes in ionic parameters of LSU ribosomal proteins. 相似文献
99.
Shailly Anand Sukanya Lal Utkarsh Sood Vipin Gupta Gauri Garg Dhingra Renu Solanki Jasvinder Kaur Roshan Kumar Anjali Saxena Ankita Dua Charu Tripathi Chandni Talwar Charu Dogra Rawat Harpreet Kaur Helianthous Verma Jaspreet Kaur Mansi Verma Mona Singh Princy Hira Nirjara Singhvi Nitish Kumar Mahato Om Prakash Jaya Malhotra Rup Lal Vipin Chandra Kalia 《Indian journal of microbiology》2021,61(4):397
100.
Renu Goel Krishna R Murthy Srinivas M Srikanth Sneha M Pinto Mitali Bhattacharjee Dhanashree S Kelkar Anil K Madugundu Gourav Dey Sujatha S Mohan Venkatarangaiah Krishna TS Keshava Prasad Shukti Chakravarti HC Harsha Akhilesh Pandey 《Clinical proteomics》2013,10(1):9