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121.
Jagrat M Behera J Yabanoglu S Ercan A Ucar G Sinha BN Sankaran V Basu A Jayaprakash V 《Bioorganic & medicinal chemistry letters》2011,21(14):4296-4300
Twenty-two pyrazoline derivatives were synthesized and tested for their human MAO (hMAO) inhibitory activity. Twelve molecules with unsubstituted ring A and substituted ring C (5-16) were found to be potent inhibitors of hMAO-A isoform with SIMAO-A in the order 103 and 104. Ten molecules with unsubstituted ring A and without ring C (21-30), in which eight molecules (21, 23-26, and 28-30) were selective for hMAO-A, one for hMAO-B (22) and the other one non-selective (27). Presence of ring C increases potency as well as SI towards hMAO-A; however its absence decreases both potency and SI towards hMAO-A and hMAO-B. 相似文献
122.
Matsuse H Behera AK Kumar M Lockey RF Mohapatra SS 《Microbes and infection / Institut Pasteur》2000,2(7):753-759
The interaction between mite allergen sensitization and respiratory syncytial virus (RSV) infection at the level of cytokine mRNA expression was examined in a murine model in the present study. Primary RSV infection enhances expression of inflammatory cytokines such as IL-6, IFN-gamma, and eotaxin in the lung and upregulates the expression of Th2-like cytokines IL-10 and IL-13 in the spleen in BALB/c mice. Mite antigen-sensitized and RSV-infected (ASRSV) mice show enhanced (P < 0.05) total serum IgE compared to antigen-sensitized mice. However, the levels of viral mRNA in the lung tissues are comparable between RSV-infected and ASRSV mice. It is concluded that compartmentalization of cytokine expression following RSV infection plays a role in the augmentation of Th2-like and IgE antibody response to RSV. 相似文献
123.
The resistance of an ecosystem to perturbations and the speed at which it recovers after the perturbations, which is called resilience, are two important components of ecosystem stability. It has been suggested that biodiversity increases the resilience and resistance of aggregated ecosystem processes. We test this hypothesis using a theoretical model of a nutrient-limited ecosystem in a heterogeneous environment. We investigate the stability properties of the model for its simplest possible configuration, i.e. , a system consisting of two plant species and their associated detritus and local resource depletion zones. Phenotypic diversity within the plant community is described by differences in the nutrient uptake and mortality rates of the two species. The usual measure of resilience characterizes the system as a whole and thus also applies to aggregated ecosystem processes. As a rule this decreases with increased diversity, though under certain conditions it is maximum for an intermediate value of diversity. Resistance is a property that characterizes each system component and process separately. The resistance of the inorganic nutrient pools, hence of nutrient retention in the ecosystem, decreases with increased diversity. The resistance of both total plant biomass and productivity either monotonically decreases or increases over part of the parameter range with increased diversity. Furthermore, it is very sensitive to parameter values. These results support the view that there is no simple relationship between diversity and stability in equilibrium deterministic systems, whether at the level of populations or aggregated ecosystem processes. We discuss these results in relation to recent experiments. 相似文献
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Cytochromes are membrane-bound hemoproteins responsible for the generation of ATP via the electron transport system to fuel the metabolic processes of the organism for their growth. This study reports the properties of cytochromes present in the isolated lichenized fungi of the cultured lichen Usnea ghattensis under optimized conditions. The fungal partner of the cultured lichen Usnea ghattensis contains a, b and c types of cytochromes. The concentrations of a, b and c type cytochromes were found to be significantly high (0.0967, 0.0900, and 0.1030 mM/mg protein, respectively) in the isolated fungal symbiont of cultured lichen grown in malt-yeast extract medium supplemented with 0.01 mol/l sucrose and 0.01 mol/l polyethylglycol. The results suggest that supplementation of additional carbon sources may play a role in optimizing the growth via activating the cytochrome respiratory system in lichenized fungi. 相似文献
126.
Calcium phosphate nanoparticles as an antigen/protein delivery was explored in a fish model Labeo rohita H. S-layer protein (of Aeromonas hydrophila) adsorbed on nano sized calcium phosphate particles elicited both innate and adaptive immune parameters which persisted up to 63 days of post immunization through parenteral immunization and gave cross protections. 相似文献
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129.
Awadhesh Kumar Darshan Panda Soumya Mohanty Monalisha Biswal Prajjal Dey Manaswini Dash Rameswar Prasad Sah Sudhir Kumar Mirza Jaynul Baig Lambodar Behera 《Physiology and Molecular Biology of Plants》2020,26(12):2465
Rice grain yield is drastically reduced under low light especially in kharif (wet) season due to cloudy weather during most part of crop growth. Therefore, 50–60% of yield penalty was observed. To overcome this problem, identification of low light tolerant rice genotypes with a high buffering capacity trait such as photosynthetic rate has to be developed. Sedoheptulose-1,7 bisphosphatase, a light-regulated enzyme, plays pivotal role in the Calvin cycle by regenerating the substrate (RuBP) for RuBisCo and therefore, indirectly regulates the influx of CO2 for this crucial process. We found a potential role of SBPase expression and activity in low light tolerant and susceptible rice genotypes by analyzing its influence on net photosynthetic rate and biomass. We observed a significant relationship of yield with photosynthesis, SBPase expression and activity especially under low light conditions. Two tolerant and two susceptible rice genotypes were used for the present study. Tolerant genotypes exhibited significant but least reduction compared to susceptible genotypes in the expression and activity of SBPase, which was also manifested in its photosynthetic rate and finally in the grain yield under low light. However, susceptible genotypes showed significant reduction in SBPase activity along with photosynthesis and grain yield suggesting that tracking the expression and activity of SBPase could form a simple and reliable method to identify the low light tolerant rice cultivars. The data were analyzed using the Indostat 7.5, Tukey–Kramer method through Microsoft Excel 2019 and PAST4.0 software. The significant association of SBPase activity with the grain yield, net assimilation rate, electron transfer rate, biomass and grain weight were observed under low light stress. These traits should be considered while selecting and breeding for low light tolerant cultivars. Thus, SBPase plays a major role in the low light tolerance mechanism in rice.Electronic supplementary materialThe online version of this article (10.1007/s12298-020-00905-z) contains supplementary material, which is available to authorized users. 相似文献
130.
Evaluation of the antimicrobial potential of two flavonoids isolated from limnophila plants 总被引:1,自引:0,他引:1
Brahmachari G Mandal NC Jash SK Roy R Mandal LC Mukhopadhyay A Behera B Majhi S Mondal A Gangopadhyay A 《化学与生物多样性》2011,8(6):1139-1151
The antimicrobial potential of two bioflavonoids, i.e., 5,7‐dihydroxy‐4′,6,8‐trimethoxyflavone ( 1 ) and 5,6‐dihydroxy‐4′,7,8‐trimethoxyflavone ( 2 ), isolated from Limnophila heterophylla Benth . and L. indica (Linn .) Druce (Scrophulariaceae), respectively, were evaluated against the microbial strains Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Salmonella typhimurium, Alternaria solani, and Candida albicans. Compounds 1 and 2 exhibited moderate but broad antimicrobial activities against both Gram‐positive and Gram‐negative bacteria and also against the fungal pathogens. Moreover, the mechanism of action of 1 and 2 on the cellular functions or structures of some of the microorganisms was studied. Compound 1 showed a bactericidal effect against E. coli and S. aureus (MICs of 200 and 250 μg/ml, resp.), while compound 2 was found to effectively kill B. subtilis by cell lysis. The growth of A. solani and C. albicans was inhibited by compounds 1 and 2 , respectively. The effects of the flavonoids on the cellular structures and the carbohydrate metabolic pathways were studied by scanning electron microscopy (SEM) of the treated cells and by assessing the specific activity of key enzymes of the pathways, respectively. At sublethal doses, they enhanced the activity of gluconeogenic fructose bisphosphatase, but decreased the activity of phosphofructokinase and isocitrate dehydrogenase, the key enzymes of the Embden Meyerhof Parnas pathway and the tricarboxylic acid cycle, respectively. 相似文献