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121.
The aim of the study was to examine the toxic effects of Monosodium glutamate (MSG), an extensively used food additive, on the contraction of uterine visceral smooth muscle (UVSM) in rat and to elucidate the probable neurocrine mechanism involved in it. MSG produced significant potentiation of the force and inhibition of frequency of uterus recorded ex vivo in chronic MSG exposure and in single dose acute experiments. MSG also produced significant potentiation of force of acetylcholine induced contraction and no alterations in atropine induced contraction of uterus. Further, MSG produced significant increase in force and frequency of contraction of neostigmine incubated uterus. We have found significant potentiation of the post pause force of contraction of uterus when MSG was applied in adrenaline incubated uterus. MSG also produced significant decrease in frequency of contraction of sodium nitroprusside incubated uterus; increase in frequency of N-ω-Nitro-l-Arginine Methyl Ester incubated uterus and no significant changes in frequency of contraction of methylene blue incubated uterus. These results indicate that MSG potentiates the force of contraction of UVSM predominantly by augmenting the activity of cholinergic intrinsic efferents and inhibits the frequency of contraction probably by augmenting the activity of nitrergic efferents. In conclusion, MSG potentiates the force and inhibits the frequency of contraction of UVSM, and the MSG induced effect is probably mediated through the augmentation of acetylcholine and nitric oxide signaling pathways.  相似文献   
122.
123.

Key message

A consensus rust QTL was identified within a 1.25 cM map interval of A03 chromosome in cultivated peanut. This map interval contains a TIR–NB–LRR R gene and four pathogenesis-related genes.

Abstract

Disease resistance in plants is manifested due to the specific interaction between the R gene product and its cognate avirulence gene product (AVR) in the pathogen. Puccinia arachidis Speg. causes rust disease and inflicts economic damages to peanut. Till now, no experimental evidence is known for the action of R gene in peanut for rust resistance. A fine mapping approach towards the development of closely linked markers for rust resistance gene was undertaken in this study. Phenotyping of an RIL population at five environments for field rust score and subsequent QTL analysis has identified a 1.25 cM map interval that harbored a consensus major Rust_QTL in A03 chromosome. This Rust_QTL is flanked by two SSR markers: FRS72 and SSR_GO340445. Both the markers clearly identified strong association of the mapped region with rust reaction in both resistant and susceptible genotypes from a collection of 95 cultivated peanut germplasm. This 1.25 cM map interval contained 331.7 kb in the physical map of A. duranensis and had a TIR–NB–LRR category R gene (Aradu.Z87JB) and four glucan endo-1,3 β glucosidase genes (Aradu.RKA6 M, Aradu.T44NR, Aradu.IWV86 and Aradu.VG51Q). Another resistance gene analog was also found in the vicinity of mapped Rust_QTL. The sequence between SSR markers, FRS72 and FRS49, contains an LRR-PK (Aradu.JG217) which is equivalent to RHG4 in soybean. Probably, the protein kinase domain in AhRHG4 acts as an integrated decoy for the cognate AVR from Puccinia arachidis and helps the TIR–NB–LRR R-protein to initiate a controlled program cell death in resistant peanut plants.
  相似文献   
124.
The present study has been aimed to the comparative analysis of high GC composition containing Corynebacterium genomes and their evolutionary study by exploring codon and amino acid usage patterns. Phylogenetic study by MLSA approach, indel analysis and BLAST matrix differentiated Corynebacterium species in pathogenic and non-pathogenic clusters. Correspondence analysis on synonymous codon usage reveals that, gene length, optimal codon frequencies and tRNA abundance affect the gene expression of Corynebacterium. Most of the optimal codons as well as translationally optimal codons are C ending i.e. RNY (R-purine, N-any nucleotide base, and Y-pyrimidine) and reveal translational selection pressure on codon bias of Corynebacterium. Amino acid usage is affected by hydrophobicity, aromaticity, protein energy cost, etc. Highly expressed genes followed the cost minimization hypothesis and are less diverged at their synonymous positions of codons. Functional analysis of core genes shows significant difference in pathogenic and non-pathogenic Corynebacterium. The study reveals close relationship between non-pathogenic and opportunistic pathogenic Corynebaterium as well as between molecular evolution and survival niches of the organism.  相似文献   
125.
Livestock depredation by carnivores cause substantial human carnivore conflict and subsequently decreased support for carnivore conservation. Thus, understanding carnivore diet with respect to wild prey availability has major implications to determine the reasons behind livestock depredation. A study was conducted to investigate food habits and prey use of tiger at four study sites (Dudhwa National Park, Kishanpur Wildlife Sanctuary, Pilibhit Forest Division and Katerniaghat Wildlife Sanctuary) in Dudhwa landscape, Terai Region, North India for further understanding of prey–predator relationship and partial impact of wild prey availability on livestock depredation by tiger through scat analysis. Scat analysis shows that the tigers depend mostly on medium sized prey throughout the study area (74.11, 73.58, 71.79, 47.62%). In Dudhwa National Park and Kishanpur Wildlife Sanctuary, predation was attempted subsequently on wider prey variety of eleven and nine different available prey species where livestock depredation were only 3.77 and 5.36% respectively. While, in absence of wider prey variety, large sized livestock (21.91, 16.55%) and nilgai (24.41, 5.57%) contributed much higher in tiger diet in Pilibhit Forest Division and Katerniaghat Wildlife Sanctuary respectively. Our study suggested that availability of prey variety has an important role in reduced livestock depredation. Medium sized preys were mostly contributing in tiger diet and seems to be a significant parameter for sustaining tiger population where abundance of large sized prey is rare. Conservation of medium sized preys is important but along with natural restoration of the population of large sized prey species like sambar and swamp deer is essential in order to reduce livestock depredation.  相似文献   
126.
Length‐weight relationships (LWRs) for three fish species from the River Ganga (India) is presented. Sampling was conducted from the lower stretch of the River Ganga (Patna: 25°36′51.66″N & 85°12′7.02″E to Freserganj: 21°35′40.58″N & 88°15′28.92″E) during April, June and September and December of 2017. Specimens were caught using gill nets (18 nos.; mesh 18–32 mm), and bag nets (3 nos.; mesh 14–22 mm). The values a and b from LWRs ‐were found to be 0.007 and 2.977 for Eutropiichthys murius; 0.003 and 3.001 for Coilia reynaldi; 0.009 and 3.010 for Johnius gangeticus.  相似文献   
127.
The ribosome-binding GTPase HflX is required for manganese homeostasis in E. coli. While under normal conditions ?hflX cells behave like wild type E. coli with respect to growth pattern and morphology, deletion of hflX makes E. coli cells extremely sensitive to manganese, characterized by arrested cell growth and filamentation. Here we demonstrate that upon complementation by hflX, manganese stress is relieved. In phenotypic studies done in a manganese-rich environment, ?hflX cells were highly sensitive to antibiotics that bind the penicillin binding protein 3 (PBP3), suggesting that the manganese stress led to impaired peptidoglycan biosynthesis. An irregular distribution of dark bands of constriction along filaments, delocalization of the dark bands from midcell towards poles and subpoles, lack of septum formation and arrested cell division were observed in ?hflX cells under manganese stress. However, chromosome replication and segregation of nucleoids were unaffected under these conditions, as observed from confocal microscopy imaging and FACS studies. We conclude that absence of HflX leads to manganese accumulation in E. coli cells, affecting cell septum formation, probably by modulating the activity of the cell division protein PBP3 (FtsI), a major component of the divisome apparatus. We propose that HflX acts as a gatekeeper, regulating the influx of manganese into the cell.  相似文献   
128.
A number of methionine, methionine+lysine-, and (methionine+lysine+isoleucine)-auxotrophic mutants producing threonine have been isolated from a glutamate-producing strain ofArthrobacter globiformis by a three-step mutagenesis with N-methyl-N′-nitro-N-nitrosoguanidine. The best double mutant ML24 requiring methionine and lysine for growth produced 3.2 gl-threonine per L in the synthetic Alföldi medium (200 mmol/L) glucose, 80 mmol/L ammonium nitrate) supplemented with 5 μg biotin per L and optimum (0.5 mmol/L) methionine and lysine concentrations.  相似文献   
129.
A study was undertaken with a view to assess the distinct pattern of sero-prevalence of influenza A viruses in the city of Calcutta population during the years of 1981–90. Concurrently, based on the fact of increasing pig population, a study was carried out to establish the activity of the human influenza A virus among pigs with a view to the potential threat of emergence of a new strain of influenza A virus that may surface following co-infection with swine and human influenza A viruses. The percentage positivity of the H3N2 antigen was found to be highest (46%), followed by H1N1 (43%), H2N2 (35%) and H0N1 (19%). A similar pattern was noted with pig sera.  相似文献   
130.
The present study investigated the peripheral plasma inhibin levels in relation to 1) the stage of estrous cycle and the effect of climatic variations. Blood samples were collected from cyclic buffalo (n=5) once daily for 32 consecutive days during the tropical hot humid (summer) and cold (winter) seasons. Estrus was recorded by parading a vasectomized bull as well as by plasma progesterone determination. In the winter season, peripheral inhibin concentrations which were lowest (0.35 +/- 0.02 ng/ml) during the mid-luteal phase of estrous cycle (Day 6 to Day 14, Day 0 = day of estrus) increased significantly (P < 0.02) to 0.47 +/- 0.04 ng/ml during the late luteal phase (Day -4 to Day -2) and then further to 0.52 +/- 0.03 ng/ml (P< 0.02) during the periestrus phase (Day -1 to Day 1). Inhibin concentrations then decreased significantly (P < 0.02) to 0.40 +/- 0.03 ng/ml during the early luteal phase (Day 2 to Day 5). In the summer season the differences in peripheral inhibin concentrations among different phases of estrous cycle were found to be nonsignificant. A comparison of the circulating inhibin concentrations between the two seasons indicated that inhibin concentrations were significantly higher in the late luteal phase (P < 0.01) and periestrus phase (P < 0.05) during the winter season compared with corresponding periods during the summer season. The present study suggests that peripheral inhibin concentrations change in the estrous cycle during cooler breeding season and that environmental heat stress can cause a reduction in peripheral inhibin concentrations.  相似文献   
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