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51.
Adnan Noor Shah Yingying Wu Mohsin Tanveer Abdul Hafeez Shahbaz Atta Tung Saif Ali Ahlam Khalofah Moodi Saham Alsubeie Rahmah N. Al-Qthanin Guozheng Yang 《Saudi Journal of Biological Sciences》2021,28(6):3578-3584
Individual effects of application of nitrogen (N) and plant densities (PD) were reported in various studies; however an interactive effect of N and PD in cotton was not studied. To explore the benefits of interactive effects of N fertilizer and PD to increase the quality of cotton. This study was carried out in randomized complete block design (RCBD) with split plot arrangement. In split plot arrangement, main plot was consisted of N application rate and in sub plots different PD were done. There were two nitrogen levels; low N level (F1) 120 kg ha−1 and high N level (F2) 180 kg ha−1 and three planting densities; 8 plants m−2 as low density (LD), 10 plants m−2 as medium density (MD) and 12 plants m−2 as high density (HD). In this study we observed the interactive effect of N application levels and PD on cotton photosynthetic and agronomic traits of various stages of development. Results showed that cotton growth and N contents was varied among treatments on different development stages. Plant biomass production, photosynthetic rate (Pn), intercellular CO2 (Ci), water use efficiency (WUE) and N contents were unaffected at the seedling stage by N application rate and PD, however, the highest Pn, Ci and N contents was at squaring stage followed by blooming stage. Higher seed cotton yield and lint yield were obtained F1 with HD, and F2 with MD yielded the highest N contents and cotton yield among treatments. We found that the squaring stage was more critical, followed by the blooming stage when considering N rate and PD. 相似文献
52.
Mohd. Moshahid Khan Tauheed Ishrat Ajmal Ahmad Md. Nasrul Hoda M. Badruzzaman Khan Gulrana Khuwaja Pallavi Srivastava Syed Shadab Raza Fakhrul Islam Saif Ahmad 《Chemico-biological interactions》2010,183(1):255-263
Restoration of blood flow to an ischemic brain region is associated with generation of reactive oxygen species (ROS) with consequent reperfusion injury. ROS cause lipid peroxidation, protein oxidation, and DNA damage, all of which are deleterious to cells. So diminishing the production of free radicals and scavenging them may be a successful therapeutic strategy for the protection of brain tissue in cerebral stroke. The present study investigated the neuroprotective effect of sesamin (Sn) to reduce brain injury after middle cerebral artery occlusion (MCAO). The middle cerebral artery (MCA) of adult male Wistar rat was occluded for 2 h and reperfused for 22 h. Sesamin is the most abundant lignan in sesame seed oil is a potent antioxidant. Sesamin (30 mg/kg) was given orally twice, 30 min before the onset of ischemia and 12 h after reperfusion. The initial investigations revealed that sesamin reduced the neurological deficits in terms of behavior and reduced the level of thiobarbituric acid reactive species (TBARS), and protein carbonyl (PC) in the different areas of the brain when compared with the MCAO group. A significantly depleted level of glutathione and its dependent enzymes (glutathione peroxidase [GPx] and glutathione reductase [GR]) in MCAO group were protected significantly in MCAO group treated with sesamin. The present study suggests that sesamin may be able to attenuate the ischemic cell death and plays a crucial role as a neuroprotectant in regulating levels of reactive oxygen species in the rat brain. Thus, sesamin may be a potential compound in stroke therapy. 相似文献
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54.
Lutz G. W. Hilgenberg Bryan Pham Maria Ortega Saif Walid Thomas Kemmerly Diane K. O'Dowd Martin A. Smith 《The Journal of biological chemistry》2009,284(25):16956-16965
Drugs that inhibit Na,K-ATPases, such as digoxin and ouabain, alter cardiac myocyte contractility. We recently demonstrated that agrin, a protein first identified at the vertebrate neuromuscular junction, binds to and regulates the activity of α3 subunit-containing isoforms of the Na,K-ATPase in the mammalian brain. Both agrin and the α3 Na,K-ATPase are expressed in heart, but their potential for interaction and effect on cardiac myocyte function was unknown. Here we show that agrin binds to the α3 subunit of the Na,K-ATPase in cardiac myocyte membranes, inducing tyrosine phosphorylation and inhibiting activity of the pump. Agrin also triggers a rapid increase in cytoplasmic Na+ in cardiac myocytes, suggesting a role in cardiac myocyte function. Consistent with this hypothesis, spontaneous contraction frequencies of cultured cardiac myocytes prepared from mice in which agrin expression is blocked by mutation of the Agrn gene are significantly higher than in the wild type. The Agrn mutant phenotype is rescued by acute treatment with recombinant agrin. Furthermore, exposure of wild type myocytes to an agrin antagonist phenocopies the Agrn mutation. These data demonstrate that the basal frequency of myocyte contraction depends on endogenous agrin-α3 Na,K-ATPase interaction and suggest that agrin modulation of the α3 Na,K-ATPase is important in regulating heart function.Na,K-ATPases, or sodium pumps, are integral membrane enzymes found in all animal cells. Using energy from the hydrolysis of ATP they transport three Na+ ions out of the cell for every two K+ ions into the cell, resulting in a transmembrane chemical gradient that is reflected in the resting membrane potential and used to drive a variety of secondary transport processes. Each Na,K-ATPase is a heterodimer consisting of an α- and β-subunit. The α-subunit is the catalytic subunit and contains the binding sites for Na+ and K+. The β-subunit is required for pump function and targeting of the α-subunit to the plasma membrane. Four α- and three β-subunit genes have been identified. All combinations of α- and β-subunits form functional pumps, but developmental, cellular, and subcellular differences in expression suggest functional adaptation of the different isoforms (1).Na,K-ATPases play a central role in regulating the contractile activity of cardiac muscle (2). They are directly responsible for the Na+ gradient required for propagation of action potentials that initiate myocyte contraction. Moreover, because of the dependence of the Na+/Ca2+ exchanger (NCX)3 on the Na+ gradient as the source of counterions for transport of Ca2+ out of the cell, they play a critical role in Ca2+ homeostasis and excitation-contraction coupling. For example, inhibition of Na,K-ATPases by digoxin, ouabain, or other cardiac glycoside results in a decline of the Na+ gradient, reducing NCX activity and Ca2+ efflux. The inotropic effects of cardiac glycosides result from uptake of this “excess” cytoplasmic Ca2+ into the sarcoplasmic reticulum, raising the level of Ca2+ in intracellular stores, which, when released during excitation, enhances muscle contraction (3).In light of the importance of Na,K-ATPases for cardiac muscle function, it is not surprising that mechanisms have evolved to regulate their activity. Na,K-ATPases are susceptible to phosphorylation by either cAMP-dependent protein kinase or protein kinase C, and neurotransmitter- and peptide hormone-dependent activation of these cytoplasmic kinases have been shown to regulate pump activity (4). Other molecules exert their effects through direct interaction with the Na,K-ATPase. For example, phospholemman, a member of the FXYD family of membrane proteins expressed in heart, is tightly associated with the Na,K-ATPase and inhibits its function (5–7). Phosphorylation of phospholemman by either protein kinase C or cAMP-dependent protein kinase, however, relieves inhibition thereby restoring the activity of the pump (8, 9). Endogenous ouabain-like compounds have also been implicated in regulating Na,K-ATPase activity (10). Ouabain, or closely related molecules, is synthesized by the adrenal gland and hypothalamus, and increased circulating levels of these compounds observed in patients with congestive heart failure has been suggested as an adaptive response to improve heart function (11). Recent studies in the central nervous system have identified the protein agrin as a new endogenous ligand that regulates Na,K-ATPase function through interaction with its extracellular domains (12).Agrin was first identified as an extracellular matrix protein at the neuromuscular junction where, by signaling through a muscle-specific receptor tyrosine kinase called MuSK, it mediates the motor neuron-induced accumulation of acetylcholine receptors in the postsynaptic muscle fiber membrane (13). Agrin is also expressed in other tissues (14–16), but its function outside of the neuromuscular junction has been less well understood. Recently, however, we showed that agrin plays a role in regulating excitability of central nervous system neurons by binding to and inhibiting the activity of the α3 subunit-containing isoform of the Na,K-ATPase (12). Although both agrin (14, 16) and the α3 Na,K-ATPase (17) are expressed in heart, their potential interaction has not been explored. Here we show that the frequency of cardiac myocyte contraction is modulated by agrin regulation of α3 Na,K-ATPase activity. 相似文献
55.
Khan S Misra AK Tripathi CK Mishra BN Bihari V 《Indian journal of experimental biology》2006,44(2):151-156
Optimization of the fermentation medium for maximum alkaline protease production was carried out with a new strain of Pseudomonas aeruginosa (B-2). Replacing the protein source/inducer (albumin in place of casein) brought about significant increase in yield after 48 hr of inoculation. Three most effective medium constituents identified by initial screening method of Plackett-Burman were albumin, (NH4)2SO4 and glucose. Central Composite Design (CCD) and Response Surface Methodology (RSM) were used in the design of the experiment and in the analysis of the results. Optimum levels of the effective medium constituents were albumin (6.586%); (NH4)2SO4, 0.164%; and glucose, 6.72%. The alkaline protease production increased from 533460 to 793492 Ul(-1). 相似文献
56.
IgY Antibodies Protect against Human Rotavirus Induced Diarrhea in the Neonatal Gnotobiotic Piglet Disease Model 总被引:1,自引:0,他引:1
CG Vega M Bok AN Vlasova KS Chattha FM Fernández A Wigdorovitz VG Parreño LJ Saif 《PloS one》2012,7(8):e42788
Group A Rotaviruses are the most common cause of severe, dehydrating diarrhea in children worldwide. The aim of the present work was to evaluate protection against rotavirus (RV) diarrhea conferred by the prophylactic administration of specific IgY antibodies (Ab) to gnotobiotic piglets experimentally inoculated with virulent Wa G1P[8] human rotavirus (HRV). Chicken egg yolk IgY Ab generated from Wa HRV hyperimmunized hens specifically recognized (ELISA) and neutralized Wa HRV in vitro. Supplementation of the RV Ab free cow milk diet with Wa HRV-specific egg yolk IgY Ab at a final ELISA Ab titer of 4096 (virus neutralization –VN- titer = 256) for 9 days conferred full protection against Wa HRV associated diarrhea and significantly reduced virus shedding. This protection was dose-dependent. The oral administration of semi-purified passive IgY Abs from chickens did not affect the isotype profile of the pig Ab secreting cell (ASC) responses to Wa HRV infection, but it was associated with significantly fewer numbers of HRV–specific IgA ASC in the duodenum. We further analyzed the pigś immune responses to the passive IgY treatment. The oral administration of IgY Abs induced IgG Ab responses to chicken IgY in serum and local IgA and IgG Ab responses to IgY in the intestinal contents of neonatal piglets in a dose dependent manner. To our knowledge, this is the first study to show that IgY Abs administered orally as a milk supplement passively protect neonatal pigs against an enteric viral pathogen (HRV). Piglets are an animal model with a gastrointestinal physiology and an immune system that closely mimic human infants. This strategy can be scaled-up to inexpensively produce large amounts of polyclonal IgY Abs from egg yolks to be applied as a preventive and therapeutic passive Ab treatment to control RV diarrhea. 相似文献
57.
Purification and characterization of adult diarrhea rotavirus: identification of viral structural proteins. 总被引:6,自引:4,他引:6 下载免费PDF全文
Z Y Fang R I Glass M Penaranda H Dong S S Monroe L Wen M K Estes J Eiden R H Yolken L Saif et al. 《Journal of virology》1989,63(5):2191-2197
Adult diarrhea rotavirus (ADRV) is a newly identified strain of noncultivable human group B rotavirus that has been epidemic in the People's Republic of China since 1982. We have used sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western (immuno-) blot analysis to examine the viral proteins present in the outer and inner capsids of ADRV and compared these with the proteins of a group A rotavirus, SA11. EDTA treatment of double-shelled virions removed the outer capsid and resulted in the loss of three polypeptides of 64, 61, and 41, kilodaltons (kDa). Endo-beta-N-acetylglucosaminidase H digestion of double-shelled virions identified the 41-kDa polypeptide as a glycoprotein. CaCl2 treatment of single-shelled particles removed the inner capsid and resulted in the loss of one polypeptide with a molecular mass of 47 kDa. The remaining core particle had two major structural proteins of 136 and 113 kDa. All of the proteins visualized on sodium dodecyl sulfate-polyacrylamide gel electrophoresis were antigenic by Western blot analysis when probed with convalescent-phase human and animal antisera. A 47-kDa polypeptide was most abundant and was strongly immunoreactive with human sera, animal sera raised against ADRV and against other group B animal rotaviruses (infectious diarrhea of infant rat virus, bovine and porcine group B rotavirus, and bovine enteric syncytial virus) and a monoclonal antibody prepared against infectious diarrhea of infant rat virus. This 47-kDa inner capsid polypeptide contains a common group B antigen and is similar to the VP6 of the group A rotaviruses. Human convalescent-phase sera also responded to a 41-kDa polypeptide of the outer capsid that seems similar to the VP7 of group A rotavirus. Other polypeptides have been given tentative designations on the basis of similarities to the control preparation of SA11, including a 136-kDa polypeptide designated VP1, a 113-kDa polypeptide designated VP2, 64- and 61-kDa polypeptides designated VP5 and VP5a, and several proteins in the 110- to 72-kDa range that may be VP3, VP4, or related proteins. The lack of cross-reactivity on Western blots between antisera to group A versus group B rotaviruses confirmed that these viruses are antigenically quite distinct. 相似文献
58.
Thomas Rath Michael Edler Wernfried Haas Achim Fischereder Stefan Moscher Alexander Schenk Roman Trattnig Meltem Sezen Gernot Mauthner Andreas Pein Dorith Meischler Karin Bartl Robert Saf Neha Bansal Saif A. Haque Ferdinand Hofer Emil J.W. List Gregor Trimmel 《Liver Transplantation》2011,1(6):1046-1050
59.
Javed Maryam Nadeem Asif Hassan Faiz-ul Mujahid Huma Rehman Saif ur 《Molecular biology reports》2022,49(10):9315-9324
Molecular Biology Reports - Poor estrus expression behavior causes suboptimal reproductive efficiency through poor conception rate. Various signaling pathways are involved in estrus expression but... 相似文献
60.