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1.
Mathew, Rajamma, Elizabeth S. Gloster, T. Sundararajan, Carl I. Thompson, Guillermo A. Zeballos, andMichael H. Gewitz. Role of inhibition of nitric oxide productionin monocrotaline-induced pulmonary hypertension. J. Appl. Physiol. 82(5): 1493-1498, 1997.Monocrotaline (MCT)-induced pulmonary hypertension (PH) isassociated with impaired endothelium-dependent nitric oxide(NO)-mediated relaxation. To examine the role of NO in PH,Sprague-Dawley rats were given a single subcutaneous injection ofnormal saline [control (C)], 80 mg/kg MCT, or the same doseof MCT and a continuous subcutaneous infusion of 2 mg · kg1 · day1of molsidomine, a NO prodrug (MCT+MD). Two weeks later, plasma NO3 levels, pulmonary arterialpressure (Ppa), ratio of right-to-left ventricular weights (RV/LV) toassess right ventricular hypertrophy, and pulmonary histology wereevaluated. The plasma NO3 level inthe MCT group was reduced to 9.2 ± 1.5 µM(n = 12) vs. C level of 17.7 ± 1.8 µM (n = 8; P < 0.02). In the MCT+MD group,plasma NO3 level was 12.3 ± 2.0 µM (n = 8). Ppa and RV/LV in theMCT group were increased compared with C [Ppa, 34 ± 3.4 mmHg(n = 6) vs. 19 ± 0.8 mmHg(n = 8) and 0.41 ± 0.01 (n = 9) vs. 0.25 ± 0.008 (n = 8), respectively;P < 0.001]. In the MCT+MDgroup, Ppa and RV/LV were not different when compared with C [19 ± 0.5 mmHg (n = 5) and 0.27 ± 0.01 (n = 9), respectively;P < 0.001 vs. MCT]. Medial wall thickness of lung vessels in the MCT group was increased comparedwith C [31 ± 1.5% (n = 9)vs. 13 ± 0.66% (n = 9);P < 0.001], and MDpartially prevented MCT-induced pulmonary vascular remodeling [22 ± 1.2% (n = 11);P < 0.001 vs. MCT and C].These results indicate that a defect in the availability of bioactive NO may play an important role in the pathogenesis of MCT-induced PH.

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A novel yellow colony-forming bacterium, strain P3B162T was isolated from the pokkali rice rhizosphere from Kerala, India, as part of a project study aimed at isolating plant growth beneficial rhizobacteria from saline tolerant pokkali rice and functionally evaluate their abilities to promote plant growth under saline conditions. The novel strain P3B162T possesses plant growth beneficial traits such as positive growth on 1-aminocyclopropane-1-carboxylic acid (ACC), production of indole acetic acid (IAA) and siderophore. In addition, it also showed important phenotypic characters such as ability to form biofilm and utilization of various components of plant root exudates (sugars, amino acids and organic acids), clearly indicating its lifestyle as a plant rhizosphere associated bacterium. Taxonomically, the novel strain P3B162T was affiliated to the genus Arthrobacter based on the collective results of phenotypic, genotypic and chemotaxonomic analyses. Moreover, molecular analysis using 16S rRNA gene showed Arthrobacter globiformis NBRC 12137T, Arthrobacter pascens DSM 20545T and Arthrobacter liuii DSXY973T as the closely related phylogenetic neighbours, showing more than 98% 16S rRNA similarity values, whereas the recA gene analysis displayed Arthrobacter liuii JCM 19864T as the nearest neighbour with 94.7% sequence similarity and only 91.7% to Arthrobacter globiformis LMG 3813T and 88.7% to Arthrobacter pascens LMG 16255T. However, the DNA-DNA hybridization values between strain P3B162T, Arthrobacter globiformis LMG 3813T, Arthrobacter pascens LMG 16255T and Arthrobacter liuii JCM 19864T was below 50%. In addition, the novel strain P3B162T can be distinguished from its closely related type strains by several phenotypic characters such as colony pigment, tolerance to NaCl, motility, reduction of nitrate, hydrolysis of DNA, acid from sucrose, cell wall sugars and cell wall peptidoglycan structure. In conclusion, the combined results of this study support the classification of strain P3B162T as a novel Arthrobacter species and we propose Arthrobacter pokkalii sp.nov.as its name. The type strain is P3B162T (= KCTC 29498T = MTCC 12358T).  相似文献   
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Antonie van Leeuwenhoek - Biofilm forming bacterium Bacillus novalis PD1 was isolated from the rhizospheric soil of a paddy field. B. novalis PD1 is a Gram-positive, facultatively anaerobic,...  相似文献   
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Russian Journal of Bioorganic Chemistry - 1,4-Dihydropyridinecarboxylates were prepared by the reaction of nicotinaldehydes with aminocrotonoates in the presence of p-TsOH at room temperature. The...  相似文献   
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Plant Cell, Tissue and Organ Culture (PCTOC) - This article has been retracted. Please see the retraction notice for more detail: https://doi.org/10.1007/s11240-020-01912-4  相似文献   
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A specific symbiotic Bacillus sp. isolated from a rhabditid entomopathogenic nematode, Rhabditis (Oscheius) sp. was found to produce large number of bioactive compounds. The present study was conducted to determine the effect of carbon and nitrogen sources for the production of antimicrobial substances by Bacillus sp. The yield of the crude antimicrobial substances and antimicrobial activity against the test micro-organism also differed significantly when carbon and nitrogen sources in the fermentation media were changed. The antifungal activity was significantly high in yeast extract plus fructose (46.5?±?2.12?mm) followed by yeast extract plus maltose, beef extract plus fructose and meat infusion plus glucose. High pressure liquid chromatography analysis of the crude antimicrobial substances revealed different peaks with different retention time indicating that they produced different compounds. When the carbon source was not included in the fermentation media, the antimicrobial production was substantially reduced. The results indicate that carbon source in the fermentation media plays a vital role in the production of antifungal substances. It is concluded that yeast extract and fructose as nitrogen and carbon sources produced maximum activity, which can effectively control the blue mould caused by Penicillium expansum in apples and pears.  相似文献   
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Penicillin-Binding Proteins are peptidases that play an important role in cell-wall biogenesis in bacteria and thus maintaining bacterial infections. A wide class of β-lactam drugs are known to act on these proteins and inhibit bacterial infections by disrupting the cell-wall biogenesis pathway. Penicillin-Binding proteins have recently gained importance with the increase in the number of multi-drug resistant bacteria. In this work, we have collected a dataset of over 700 Penicillin-Binding and non-Penicillin Binding Proteins and extracted various sequence-related features. We then created models to classify the proteins into Penicillin-Binding and non-binding using supervised machine learning algorithms such as Support Vector Machines and Random Forest. We obtain a good classification performance for both the models using both the methods.  相似文献   
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