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991.
It is of interest to report the chemotherapeutic (drug target based) potential of n-hexane Cayratia trifolia L. (C.trifolia) extract on A2780 cell lines. mRNA and protein expression analysis of the human chemokine receptor (CXCR4) and human epidermal growth factor receptors-2 (HER2) were studied using RT-PCR analysis and western blot analysis. The results show significant cell growth inhibition with minimal IC50 values of 46.25 ± 0.42 micro g/mL against A2780 cell lines. mRNA and protein expression were considerably reduced in C. trifoliatreated A2780 cell lines for further consideration as a chemotherapeutic agents.  相似文献   
992.
Embelia ribes, an important vulnerable medicinal liana, was regenerated through organogenesis and embryogenesis using leaf explants. Leaf explants produced organogenic calluses on MS medium supplemented with 1.0 mg l−1 2,4-dichlorophenoxy acetic acid (2,4-D) and 0.5 mg l−1 6-benzylaminopurine. Shoot regeneration was obtained from organogenic calluses on MS medium containing different concentrations of thidiazuron (TDZ) and indole-3-acetic acid (IAA). The frequency of shoot bud organogenesis was highest (23.9 shoots/explant) in MS medium containing 0.5 mg l−1 TDZ and 0.1 mg l−1 IAA. The best result for induction of embryogenic callus was noticed in the combination of 2.0 mg l−1 TDZ and 0.5 mg l−1 2,4-D. This callus, maintained in the same medium, showed the highest differentiation of embryos (56.5%) after 6 wk of culture. Embryos were transferred to MS medium supplemented with different concentrations of TDZ, and this facilitated conversion of embryos into plants. After 6 wk of subculture, MS medium with 0.05 mg l−1 TDZ favored the highest percentage (52.2%) embryo conversion. As per the present protocol, 52.2% of the embryos underwent conversion, and a mean number of 29.5 shoots per culture was obtained. Shoots developed from both types of calluses were rooted on half-strength MS basal medium supplemented with 1.0 mg l−1 indole-3-butyric acid. HPLC-UV assay demonstrated the highest embelin content (5.33% w/w) in the embryogenic callus cultures. Embelin was isolated from embryogenic callus and was identified using IR and 1H NMR studies.  相似文献   
993.
BackgroundPhysicians with a large number of reviews and a high rating may be employing reputation management strategies. Specialists may be more likely than non-specialists to employ such strategies. This should be apparent in a study of online physician reviews on physician rating websites (PRW).MethodsUsing one physician rating website, we gathered orthopedic surgeon and family physician reviews. We measured Spearman correlations between the number of reviews and average numerical rating and used chi-squared to test threshold relationships.ResultsThere were very small negative Spear-man correlations between the number of online reviews and the average numerical rating for orthopedic surgeons (p= -0.097, p-value=<0.001) family medicine physicians (p= -0.170, p-value=<0.001; Figure 2). Physicians with more than 100 reviews had a greater average numerical rating than physicians with fewer than 50 reviews. Orthopedic surgeons are more likely than family medicine physicians to have a large number of reviews and average numerical rating greater than 3.Open in a separate windowFigure 2.Family medicine physicians average rating plotted against number of reviews.ConclusionThe small fraction of physician with a high number of reviews may be utilizing reputation management strategies, and this seems relatively specific to specialists rather than non-specialists. Level of Evidence: III  相似文献   
994.
The Zebrafish Information Network (zfin.org) is the central repository for Danio rerio genetic and genomic data. The Zebrafish Information Network has served the zebrafish research community since 1994, expertly curating, integrating, and displaying zebrafish data. Key data types available at the Zebrafish Information Network include, but are not limited to, genes, alleles, human disease models, gene expression, phenotype, and gene function. The Zebrafish Information Network makes zebrafish research data Findable, Accessible, Interoperable, and Reusable through nomenclature, curatorial and annotation activities, web interfaces, and data downloads. Recently, the Zebrafish Information Network and 6 other model organism knowledgebases have collaborated to form the Alliance of Genome Resources, aiming to develop sustainable genome information resources that enable the use of model organisms to understand the genetic and genomic basis of human biology and disease. Here, we provide an overview of the data available at the Zebrafish Information Network including recent updates to the gene page to provide access to single-cell RNA sequencing data, links to Alliance web pages, ribbon diagrams to summarize the biological systems and Gene Ontology terms that have annotations, and data integration with the Alliance of Genome Resources.  相似文献   
995.
BackgroundType 2 Diabetes mellitus (T2DM) is a chronic metabolic disorder. It is a major non-communicable disease affecting 463 million people globally in 2019 and is expected to be double to about 700 million by 2045. The majority are Asians with Indian ethnicity in Malaysia reported as the highest prevalence of T2DM. Cardiovascular disease, renal failure, blindness and neuropathy, as well as premature death are the known morbidity and mortality resulted from T2DM. T2DM is characterized by the dysfunctional insulin physiology that causes reduction of glucose transport into the cells which lead to hyperglycaemia. Hence, one of the important treatments is an oral antidiabetic drug that lowers the serum glucose level in patients with T2DM. This drug will be transported across cell membranes by organic cation transporters (OCT). Therefore, it is important to identify the OCT candidate gene polymorphisms related to T2DM especially among the Indian ethnicity in Malaysia.MethodsBlood samples were collected from 132 T2DM patients and 133 controls. Genotyping of OCT1 (rs628031), OCT2 (rs145450955), OCT3 (rs3088442 and rs2292334) was performed using (PCR-RFLP).ResultsNo association was observed for genotypic and allelic distributions in all the gene polymorphisms of OCT genes (P > 0.05). However, a logistic regression analysis stratified by gender in a dominant model showed a significant difference for OCT3 among males with T2DM (P = 0.006). Significant association was also observed for OCT3 when stratified to subjects aged > 45 years old (P = 0.009).ConclusionBased on these findings, the association of OCT3 (rs2292334) could be considered as a possible genetic risk factor for the development of T2DM among Indian males alone.  相似文献   
996.

Cymbopogon

is an important member of grass family Poaceae, cultivated for essential oils which have greater medicinal and industrial value. Taxonomic identification of Cymbopogon species is determined mainly by morphological markers, odour of essential oils and concentration of bioactive compounds present in the oil matrices which are highly influenced by environment. Authenticated molecular marker based taxonomical identification is also lacking in the genus; hence effort was made to evaluate potential DNA barcode loci in six commercially important Cymbopogon species for their individual discrimination and authentication at the species level. Four widely used DNA barcoding regions viz., ITS 1 & ITS 2 spacers, matK, psbA-trnH and rbcL were taken for the study. Gene sequences of the same or related genera of the concerned loci were mined from NCBI domain and primers were designed and validated for barcode loci amplification. Out of the four loci studied, sequences from matK and ITS spacer loci revealed 0.46% and 5.64% nucleotide sequence diversity, respectively whereas the other two loci i.e., psbA-trnH and rbcL showed 100% sequence homology. The newly developed primers can be used for barcode loci amplification in the genus Cymbopogon. The identified Single Nucleotide Polymorphisms from the studied sequences may be used as barcodes for the six Cymbopogon species. The information generated can also be utilized for barcode development of the genus by including more number of Cymbopgon species in future.
  相似文献   
997.
The biochemical contents and biodiesel production ability of three microalgal strains grown under different sodium nitrate, sodium carbonate, and ferric ammonium citrate (iron) levels were investigated. The highest biomass and lipid contents were found in Scenedesmus sp., Chlorella sp., and Chlamydomonas sp. when grown in normal BG‐11 containing sodium carbonate concentration at 0.03 g · L?1, and in normal BG‐11 containing iron concentration (IC) at 0.009 or 0.012 g · L?1. Increasing the sodium nitrate level increased the biomass content, but decreased the lipid content in all three microalgae. Among the three microalgae, Scenedesmus sp. showed the highest total lipid yield of 0.69 g · L?1 under the IC of 0.012 g · L?1. Palmitic and oleic acids were the major fatty acids of Scenedesmus sp. and Chlamydomonas sp. lipids. On the other hand, Chlorella sp. lipids were rich in palmitic, oleic, and linolenic acids, and henceforth contributing to poor biodiesel properties below the standard limits. The three isolated strains had a potential for biodiesel production. Nevertheless, Scenedesmus sp. from stone quarry pond water was the most suitable source for biodiesel production with tolerance toward the high concentration of sodium carbonate without the loss of its biodiesel properties.  相似文献   
998.
To investigate the effects of iontophoresis–ultraviolet A (UVA) cross-linking (CXL) with hypotonic riboflavin solution on the ultrastructural changes in the lamellae, collagen fibrils (CFs), and proteoglycans (PGs) in the central and peripheral stroma of the human corneal buttons. The iontophoresis method was used for the trans-epithelial application of hypotonic riboflavin in ex vivo corneal culture for 5 min. The corneas were irradiated using three methods: Group 1 (G1), a UVA irradiance of 3 mW/cm2 for 30 min; Group 2 (G2), a UVA irradiance of 10 mW/cm2 for 9 min; Group 3 (G3), without UVA irradiation. Three untreated corneas were used as controls (G0). After the CXL procedure, the corneas were processed for electron microscopy. The CF diameter and PGs in each sample were analyzed using the iTEM program. The keratocyte organelles and stromal architecture in the peripheral cornea were better preserved than those in the central cornea. In G1 and G2, the mean CF diameter in the peripheral cornea was significantly higher than that in the central cornea. In G3, the CF diameter in the central cornea was significantly larger than that in the peripheral cornea. Furthermore, differences in PG area size were observed between the central and peripheral corneas in all groups. Riboflavin + UVA application at 3 mW/cm2 for 30 min and 10 mW/cm2 for 9 min was a suitable method of CXL; however, 3 mW/cm2 for 30 min improved the organization and size of the collagen fibrils. CXL treatment applied at the periphery was more effective than that applied at the center.Keyword: Collagen fibrils, Proteoglycans, Cornea, Iontophoresis, Ultraviolet A  相似文献   
999.
Herein, we demonstrate that the ubiquitin-associated (UBA) domain of sequestosome 1/p62 displays a preference for binding K63-polyubiquitinated substrates. Furthermore, the UBA domain of p62 was necessary for aggregate sequestration and cell survival. However, the inhibition of proteasome function compromised survival in cells with aggregates. Mutational analysis of the UBA domain reveals that the conserved hydrophobic patch MGF as well as the conserved leucine in helix 2 are necessary for binding polyubiquitinated proteins and for sequestration-aggregate formation. We report that p62 interacts with the proteasome by pull-down assay, coimmunoprecipitation, and colocalization. Depletion of p62 levels results in an inhibition of ubiquitin proteasome-mediated degradation and an accumulation of ubiquitinated proteins. Altogether, our results support the hypothesis that p62 may act as a critical ubiquitin chain-targeting factor that shuttles substrates for proteasomal degradation.  相似文献   
1000.
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