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The genetic variability among accessions ofProsopis was determined using randomly amplified polymorphic DNA (RAPD) profiles. Similarities of profiles were determined using the algorithm of Jaccard, and UPGMA and neighbour joining trees were generated from the similarity data. The average similarity was highest among the accessions ofP. glandulosa (0.52 ± 0.18) and least in the accessions ofP. juliflora (0.37 ± 0.15), indicating that the latter species has greater diversity among accessions. Our observations suggest that RAPD analysis could help in identifying genetic variations among different accessions ofProsopis.  相似文献   
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Complete or partial depletion of resource in a freshwater habitat is a common phenomenon. As a consequence, aquatic fauna including bivalve molluscs may be exposed to dietary stress on a seasonal basis. Haemocyte based innate immune profile of the freshwater mollusc Lamellidens marginalis (Bivalvia: Eulamellibranchiata) was evaluated under starvation induced stress for a maximum period of 32 days in a controlled laboratory condition. During starvation, the bivalve haemocytes maintained a homeostasis in phagocytic efficacy and nitric oxide generation ability with respect to the control. The mollusc maintained a significantly high protein content in its haemolymph and tissues under the nutritional stress with respect to the control. The dietary stress had no significant impact on the activity of digestive tissue derived α-amylase till sixteenth day but by 32 days the enzyme activity went down significantly. The histopathological profile revealed that the bivalve was adapted to maintain a steady immune profile by incurring degeneration of its own tissue structure. The total haemocyte count surged significantly till 16 days but differed insignificantly with respect to the control at 32 days implying probable haematopoietic exhaustion. The study reflects the instinctive urge of the bivalve to maintain immune physiology at heavy metabolic cost under nutrient limited condition.  相似文献   
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Isorhamnetin, a flavonoid compound extracted from the Chinese herb Hippophae rhamnoides L., is well known for its anti-inflammatory, anti-oxidative, anti-adipogenic, anti-proliferative, and anti-tumor activities. However, the role of isorhamnetin in cardiac hypertrophy has not been reported. The aims of the present study were to find whether isorhamnetin could alleviate cardiac hypertrophy and to define the underlying molecular mechanisms. Here, we investigated the effects of isorhamnetin (100 mg/kg/day) on cardiac hypertrophy induced by aortic banding in mice. Cardiac hypertrophy was evaluated by echocardiographic, hemodynamic, pathological, and molecular analyses. Our data demonstrated that isorhamnetin could inhibit cardiac hypertrophy and fibrosis 8 weeks after aortic banding. The results further revealed that the effect of isorhamnetin on cardiac hypertrophy was mediated by blocking the activation of phosphatidylinositol 3-kinase–AKT signaling pathway. In vitro studies performed in neonatal rat cardiomyocytes confirmed that isorhamnetin could attenuate cardiomyocyte hypertrophy induced by angiotensin II, which was associated with phosphatidylinositol 3-kinase–AKT signaling pathway. In conclusion, these data indicate for the first time that isorhamnetin has protective potential for targeting cardiac hypertrophy by blocking the phosphatidylinositol 3-kinase–AKT signaling pathway. Thus, our study suggests that isorhamnetin may represent a potential therapeutic strategy for the treatment of cardiac hypertrophy and heart failure.  相似文献   
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The feasibility of Fourier transform infrared (FT-IR) microscopy to monitor in situ the enzymatic degradation of wood was investigated. Cross-sections of poplar wood were treated with cellulase Onozuka RS within a custom-built fluidic cell. Light-optical micrographs and FT-IR spectra were acquired in situ from normal and tension wood fibers. Light-optical micrographs showed almost complete removal of the gelatinous (G) layer in tension wood. No structural and spectral changes were observed in the lignified cell walls. The accessibility of cellulose within the lignified cell wall was found to be the main limiting factor, whereas the depletion of the enzyme due to lignin adsorption could be ruled out. The fast, selective hydrolysis of the crystalline cellulose in the G-layer, even at room temperature, might be explained by the gel-like structure and the highly porous surface. Young plantation grown hardwood trees with a high proportion of G-fibers thus represent an interesting resource for bioconversion to fermentable sugars in the process to bioethanol.  相似文献   
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Design, synthesis and conformational analysis of few imidazole and oxazole as bioisosters of 4S-(-)-3-(4-chlorophenyl)-N-methyl-N'-[(4-chlorophenyl)-sulfonyl]-4-phenyl-4,5-dihydro-1H-pyrazole-1-caboxamidine (SLV-319) 2 is reported. Computer assisted conformational analysis gave a direct clue for the loss of CB1 antagonistic activity of the ligands without a fine docking simulation for the homology model.  相似文献   
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In the present study, methanolic extracts of roots of Vitex negundo L. and extracts of leaves of Vitex negundo L., Ricinus communis L. and Aegle marmelos Corr. were explored for possible antifilarial effect against Brugia malayi microfilariae. It was observed that among the herbal extracts, root extract of Vitex negundo L. and leaves extract of Aegle marmelos Corr. at 100 ng/ml concentration showed complete loss of motility of microfilariae after 48 hr of incubation. Thin layer chromatography of the extracts revealed the presence of alkaloids, saponin and flavonoids in the roots of Vitex negundo L. and coumarin in the leaves of Aegle marmelos Corr.  相似文献   
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Homology models of amidase-03 from Bacillus anthracis were constructed using Modeller (9v2). Modeller constructs protein models using an automated approach for comparative protein structure modeling by the satisfaction of spatial restraints. A template structure of Listeria monocytogenes bacteriophage PSA endolysin PlyPSA (PDB ID: 1XOV) was selected from protein databank (PDB) using BLASTp with BLOSUM62 sequence alignment scoring matrix. We generated five models using the Modeller default routine in which initial coordinates are randomized and evaluated by pseudo-energy parameters. The protein models were validated using PROCHECK and energy minimized using the steepest descent method in GROMACS 3.2 (flexible SPC water model in cubic box of size 1 Å instead of rigid SPC model). We used G43a1 force field in GROMACS for energy calculations and the generated structure was subsequently analyzed using the VMD software for stereo-chemistry, atomic clash and misfolding. A detailed analysis of the amidase-03 model structure from Bacillus anthracis will provide insight to the molecular design of suitable inhibitors as drug candidates.  相似文献   
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