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71.
The root-tuber peel of Flemingia vestita, an indigenous leguminous plant of Meghalaya (Northeast India), has usage in local traditional medicine as curative against worm infections. The peel and its active component, genistein, have been shown to cause flaccid paralysis, deformity of tegumental architecture and alterations in the activity of several enzymes in platyhelminth parasites. To investigate further the mode of action and anthelmintic efficacy of the plant-derived components, the crude peel extract of F. vestita and genistein were tested, hitherto for the first time, in respect of the unique neuronal messenger nitric oxide (NO) and the enzyme nitric oxide synthase (NOS) in Fasciolopsis buski, the large intestinal fluke of swine and human host. NADPH-diaphorase histochemical staining (a selective marker for NOS in neuronal tissues), which was demonstrable in the neuronal cell bodies in the cerebral ganglia, the brain commissure, the main nerve cords and in the innervation of the pharynx, ventral sucker, terminal genitalia and genital parenchyma of the parasite, showed a stronger activity in the treated worms. In biochemical analysis also, the NOS activity showed a significant increase in the parasites treated with the test materials and reference drug, compared to the untreated controls. The increase in NOS activity in the treated parasites can be attributed to an inducing effect of the plant-derived components.  相似文献   
72.
Microtubule associated tumor suppressor 1 (MTUS1) has been recognized as a tumor suppressor gene in multiple cancers. However, the molecular mechanisms underlying the regulation of MTUS1 are yet to be investigated. This study aimed to clarify the significance of DNA methylation in silencing MTUS1 expression. We report that MTUS1 acts as tumor suppressor in non-small cell lung carcinoma (NSCLC). Analysis of in silico database and subsequent knockdown of DNMT1 suggested an inverse correlation between DNMT1 and MTUS1 function. Interestingly, increased methylation at MTUS1 promoter is associated with low expression of MTUS1. Treatment with DNA methyltransferases (DNMTs) inhibitor, 5-aza-2′-deoxycytidine (AZA) leads to both reduced promoter methylation accompanied with enrichment of H3K9Ac and enhanced MTUS1 expression. Remarkably, knockdown of MTUS1 showed increased proliferation and migration of NSCLC cells in contrast to diminished proliferation and migration, upon treatment with AZA. We concluded that low expression of MTUS1 correlates to DNA methylation and histone deacetylation in human NSCLC.  相似文献   
73.
Study of genetic diversity in crop plants is essential for the selection of appropriate germplasm for crop improvement. As salinity posses a serious environmental challenge to rice production globally and especially in India, it is imperative that the study of large collections of germplasms be undertaken to search for salt tolerant stocks. In the present study, 64 indica germplasms were collected from different agro-climatic zones of West Bengal, India, from the Himalayan foothills in the northern part down to the southern saline belt of the state keeping in view the soil characteristics and other edaphic factors prevailing in the region. Salt tolerance parameters were used to screen the large set of germplasms in terms of root-shoot length, fresh-dry weight, chlorophyll content, Na+/K+ ratio and germination potential in presence of salt. Standard evaluation score or SES was calculated to find out tolerant to sensitive cultivar. Twenty-one SSR markers, some associated with the Saltol QTL and others being candidate gene based SSR (cgSSR) were used to study the polymorphism of collected germplasm. A wide diversity was detected among the collected germplasms at the phenotypic as well as molecular level. Of the 21 SSR markers, 15 markers were found to be polymorphic with 88 alleles. Based on phenotypic and biochemical results, 21 genotypes were identified as salinity tolerant, whereas 40 genotypes turned out to be salt susceptible. The present study shows that apart from the established salt tolerant lines, several other landraces like Bonkanta, Morisal, Ghiosh, Patni may be the source of salt tolerant donor in future breeding programs.  相似文献   
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Formation of the cardiac valves is an essential component of cardiovascular development. Consistent with the role of the bone morphogenetic protein (BMP) signaling pathway in cardiac valve formation, embryos that are deficient for the BMP regulator BMPER (BMP-binding endothelial regulator) display the cardiac valve anomaly mitral valve prolapse. However, how BMPER deficiency leads to this defect is unknown. Based on its expression pattern in the developing cardiac cushions, we hypothesized that BMPER regulates BMP2-mediated signaling, leading to fine-tuned epithelial-mesenchymal transition (EMT) and extracellular matrix deposition. In the BMPER-/- embryo, EMT is dysregulated in the atrioventricular and outflow tract cushions compared with their wild-type counterparts, as indicated by a significant increase of Sox9-positive cells during cushion formation. However, proliferation is not impaired in the developing BMPER-/- valves. In vitro data show that BMPER directly binds BMP2. In cultured endothelial cells, BMPER blocks BMP2-induced Smad activation in a dose-dependent manner. In addition, BMP2 increases the Sox9 protein level, and this increase is inhibited by co-treatment with BMPER. Consistently, in the BMPER-/- embryos, semi-quantitative analysis of Smad activation shows that the canonical BMP pathway is significantly more active in the atrioventricular cushions during EMT. These results indicate that BMPER negatively regulates BMP-induced Smad and Sox9 activity during valve development. Together, these results identify BMPER as a regulator of BMP2-induced cardiac valve development and will contribute to our understanding of valvular defects.  相似文献   
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Plants encode a poorly understood superfamily of developmentally expressed cell wall hydroxyproline‐rich glycoproteins (HRGPs). One, EXTENSIN3 (EXT3) of the 168 putative HRGPs, is critical in the first steps of new wall assembly, demonstrated by broken and misplaced walls in its lethal homozygous mutant. Here we report the findings of phenotypic (not genotypic) revertants of the ext3 mutant and in‐depth analysis including microarray and qRT‐PCR (polymerase chain reaction). The aim was to identify EXT3 substitute(s), thus gaining a deeper understanding of new wall assembly. The data show differential expression in the ext3 mutant that included 61% (P ≤ 0.05) of the HRGP genes, and ability to self‐rescue by reprogramming expression. Independent revertants had reproducible expression networks, largely heritable over the four generations tested, with some genes displaying transgenerational drift towards wild‐type expression levels. Genes for nine candidate regulatory proteins as well as eight candidate HRGP building materials and/or facilitators of new wall assembly or maintenance, in the (near) absence of EXT3 expression, were identified. Seven of the HRGP fit the current model of EXT function. In conclusion, the data on phenotype comparisons and on differential expression of the genes‐of‐focus provide strong evidence that different combinations of HRGPs regulated by alternative gene expression networks, can make functioning cell walls, resulting in (apparently) normal plant growth and development. More broadly, this has implications for interpreting the cause of any mutant phenotype, assigning gene function, and genetically modifying plants for utilitarian purposes.  相似文献   
79.
Tarap Hill Reserve, the largest upland reserve of Bangladesh, is situated along the Indo-Burma Biodiversity Hotspot. It encompasses the last remaining patches of natural vegetation in the Northeastern Tarap Mountain System and harbors 87 % of the nationally declared red-listed vascular plant species. Despite requiring high conservation priority, this is one of the least studied reserves in the tropics. In this study, we collected vegetation and soil (eight variables) data from 68 sample plots. We identified the tree communities by cluster analysis and verified them using the multi-response permutation procedure and detrended correspondence analysis. Species richness, diversity, and compositional similarity between the communities were also estimated. In total, 116 tree species representing 69 genera were recorded within the four identified tree community types. Finally, canonical correspondence analysis with associated Monte Carlo permutation tests (499 permutations) was performed to explore the patterns of variation in tree species distribution explained by the soil variables. Soil phosphorus, organic matter content, and pH were most closely correlated with tree compositional variation. Thus, conservation strategies that take into account variations in these influential soil factors may aid in the conservation of trees in the reserve.  相似文献   
80.
Rohu (Labeo rohita) fingerlings, were fed de-oiled Jatropha curcas seed meal (DJSM) supplemented diets for 60 days and the effectiveness, if any, on the growth was evaluated. Nine isonitrogenous (35 % crude protein) and isocaloric (4.0 kcal g?1) diets were formulated of which one was reference diet (RD, fishmeal based control diet) and the other eight were experimental diets prepared by incorporating raw (D1–D4) and fermented (D5–D8) DJSM at 10, 20, 30 and 40 % levels by weight, respectively. Autoclaved DJSM was processed through solid state fermentation (SSF) for 15 days at 37 ± 1 °C by an exo-enzyme producing bacterium, Bacillus cereus Lr.H.23 isolated from the hindgut of rohu, L. rohita. Processing through SSF caused decrease in the contents of crude fibre and anti-nutritional factors, but increase in the levels of free amino acids and free fatty acids. In terms of growth performance, feed utilization efficiency and apparent protein digestibility, fish fed diet D7 containing 30 % fermented DJSM showed the best performance, which differed significantly (P < 0.05) from that of the fish fed diets containing raw DJSM. The results indicated that an inclusion level up to 30 % fermented DJSM replacing 15 % FM in the practical diet for rohu fingerlings can be proposed when compared to the RD. However, further experiments are required to recommend the ingredient for use in industry.  相似文献   
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