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221.
Summary The size distribution of cell aggregates, and the effect of cell aggregate size on anthocyanin content of Daucus carota cells in suspension cultures, was studied. The profile of biomass distribution in various size groups of cell aggregates indicated that over 92% of biomass was present in the aggregates of 500–1500 m in diameter. The anthocyanin content increased initially with the increase in cell aggregate diameter up to 500–850 m, and decreased rapidly with the increase in the cell aggregate size above this critical diameter. On the other hand, the surface colour intensity showed a steady increase with the increase in cell aggregate size, indicating a steep radial gradient of anthocyanin content along the radius of the larger cell aggregates. 相似文献
222.
Lim SS Fullman N Stokes A Ravishankar N Masiye F Murray CJ Gakidou E 《PLoS medicine》2011,8(9):e1001091
Background
Several sub-Saharan African countries have rapidly scaled up the number of households that own insecticide-treated mosquito nets (ITNs). Although the efficacy of ITNs in trials has been shown, evidence on their impact under routine conditions is limited to a few countries and the extent to which the scale-up of ITNs has improved population health remains uncertain.Methods and Findings
We used matched logistic regression to assess the individual-level association between household ITN ownership or use in children under 5 years of age and the prevalence of parasitemia among children using six malaria indicator surveys (MIS) and one demographic and health survey. We used Cox proportional hazards models to assess the relationship between ITN household ownership and child mortality using 29 demographic and health surveys. The pooled relative reduction in parasitemia prevalence from random effects meta-analysis associated with household ownership of at least one ITN was 20% (95% confidence interval [CI] 3%–35%; I 2 = 73.5%, p<0.01 for I 2 value). Sleeping under an ITN was associated with a pooled relative reduction in parasitemia prevalence in children of 24% (95% CI 1%–42%; I 2 = 79.5%, p<0.001 for I 2 value). Ownership of at least one ITN was associated with a pooled relative reduction in mortality between 1 month and 5 years of age of 23% (95% CI 13–31%; I 2 = 25.6%, p>0.05 for I 2 value).Conclusions
Our findings across a number of sub-Saharan African countries were highly consistent with results from previous clinical trials. These findings suggest that the recent scale-up in ITN coverage has likely been accompanied by significant reductions in child mortality and that additional health gains could be achieved with further increases in ITN coverage in populations at risk of malaria. Please see later in the article for the Editors'' Summary 相似文献223.
224.
Vinod Kumar M. Madhava Naidu G. A. Ravishankar 《Plant Cell, Tissue and Organ Culture》2006,87(1):49-65
Coffee is an important plantation crop grown in about 80 countries across the globe. In recent years, coffee attained lot of attention in the biotechnology research area. Since last three decades, there has been a steady flow of information on coffee biotechnology and now it is entering into the genomic era. Major milestones in coffee biotech research are successful in vitro manipulation and multiplication of coffee, development of gene transfer protocols and generation of transgenic coffee plants with specific traits. The isolation of genes involved in caffeine biosynthetic pathway has opened up new avenues for generating caffeine free transgenic coffee. With the initiation of international coffee genomics initiatives, the genomic research in coffee is expected to reach new dimensions. The IPR issues may play crucial role in sharing of benefits during international collaborations in near future. This review focuses on the basic and applied aspects of coffee biotechnology for newer potentials. 相似文献
225.
Ramalingam Sundaram Palanivelu Shanthi Panchanatham Sachdanandam 《Molecular and cellular biochemistry》2013,380(1-2):43-55
The present study was designed to examine the antihyperlipidaemic potential of iridoid glucoside isolated from Vitex negundo leaves in STZ-induced diabetic rats. The levels of cholesterol (TC), triglycerides, lipoproteins, free fatty acids, phospholipids, fatty acid composition, proinflammatory cytokines, muscle glycogen content, and glucose transporter 4 (GLUT4) expression were estimated in control and diabetic rats. Oral administration of iridoid glucoside at a dose of 50 mg/kg body weight per day to STZ-induced diabetic rats for a period of 30 days resulted in a significant reduction in plasma and tissue (liver and kidney) cholesterol, triglycerides, free fatty acids, and phospholipids. In addition, the decreased plasma levels of high-density lipoprotein-cholesterol and increased plasma levels of low density lipoprotein- and very low density lipoprotein-cholesterol in diabetic rats were restored to near normal levels following treatment with iridoid glucoside. The fatty acid composition of the liver and kidney was analyzed by gas chromatography. The altered fatty acid composition in the liver and kidney of diabetic rats was also restored upon treatment with iridoid glucoside. Moreover, the elevated plasma levels of proinflammatory cytokines and decreased levels of muscle glycogen and GLUT4 expression in the skeletal muscle of diabetic rats were reinstated to their normal levels via enhanced secretion of insulin from the remnant β cells of pancreas by the administration of iridoid glucoside. The effect produced by iridoid glucoside on various parameters was comparable with that of glibenclamide, a well-known antihyperglycemic drug. 相似文献
226.
227.
Justus Hammon Dinesh V. Palanivelu Joy Chen Chintan Patel Daniel L. Minor Jr. 《Protein science : a publication of the Protein Society》2009,18(1):121-133
Green fluorescent protein (GFP) fusion proteins provide a potentially facile tool for identification of well expressed, properly behaved membrane proteins for biochemical and structural study. Here, we present a GFP-expression survey of >300 membrane proteins from 18 bacterial and archaeal extremophiles, organisms expected to be rich sources of membrane proteins having robust biophysical properties. We find that GFP-fusion fluorescence intensity is an excellent indicator of over-expression potential. By employing a follow-up optimization protocol using a suite of non-GFP constructs and different expression temperatures, we obtain 0.5–15 mg L−1 expression levels for 90% of the tested candidate proteins that pass the GFP screen. Evaluation of the results suggests that certain organisms may serve as better sources of well-expressed membrane proteins than others, that the degree to which codon usage matches the expression host is uncorrelated with success rate, and that the combination of GFP screening and expression optimization is essential for producing biochemically tractable quantities of material. 相似文献
228.
229.
Jastin Samuel Madona Lien Paul Harish Ravishankar Ankita Mathur Dipti Priya Saha Chandrasekaran Natarajan Amitava Mukherjee 《Biodegradation》2013,24(6):829-842
In the current study, indigenous bacterial isolates Bacillus subtilis VITSUKMW1 and Escherichia coli VITSUKMW3 from a chromite mine were adapted to 100 mg L?1 of Cr(VI). The phase contrast and scanning electron microscopic images showed increase in the length of adapted E. coli cells and chain formation in case of adapted B. subtilis. The presence of chromium on the surface of the bacteria was confirmed by energy dispersive X-ray spectroscopy (EDX), which was also supported by the conspicuous Cr–O peaks in FTIR spectra. The transmission electron microscopic (TEM) images of adapted E. coli and B. subtilis showed the presence of intact cells with Cr accumulated inside the bacteria. The TEM–EDX confirmed the internalization of Cr(VI) in the adapted cells. The specific growth rate and Cr(VI) reduction capacity was significantly higher in adapted B. subtilis compared to that of adapted E. coli. To study the possible role of Cr(VI) toxicity affecting the Cr(VI) reduction capacity, the definite assays for the released reactive oxygen species (ROS) and ROS scavenging enzymes (SOD and GSH) were carried out. The decreased ROS production as well as SOD and GSH release observed in adapted B. subtilis compared to the adapted E. coli corroborated well with its higher specific growth rate and increased Cr(VI) reduction capacity. 相似文献
230.
Kannan Vaidyanathan Smita Lakhotia H. M. Ravishankar Umaira Tabassum Geetashree Mukherjee Kumaravel Somasundaram 《Journal of biosciences》2009,34(3):415-422
Mutations in the BRCA1 and BRCA2 genes profoundly increase the risk of developing breast and/or ovarian cancer among women. To explore the contribution of
BRCA1 and BRCA2 mutations in the development of hereditary breast cancer among Indian women, we carried out mutation analysis of the BRCA1 and BRCA2 genes in 61 breast or ovarian cancer patients from south India with a positive family history of breast and/or ovarian cancer.
Mutation analysis was carried out using conformation-sensitive gel electrophoresis (CSGE) followed by sequencing. Mutations
were identified in 17 patients (28.0%); 15 (24.6%) had BRCA1 mutations and two (3.28%) had BRCA2 mutations. While no specific association between BRCA1 or BRCA2 mutations with cancer type was seen, mutations were more often seen in families with ovarian cancer. While 40% (4/10) and
30.8% (4/12) of families with ovarian or breast and ovarian cancer had mutations, only 23.1% (9/39) of families with breast
cancer carried mutations in the BRCA1 and BRCA2 genes. In addition, while BRCA1 mutations were found in all age groups, BRCA2 mutations were found only in the age group of ≤40 years. Of the BRCA1 mutations, there were three novel mutations (295delCA; 4213T→A; 5267T→G) and three mutations that have been reported earlier.
Interestingly, 185delAG, a BRCA1 mutation which occurs at a very high frequency in Ashkenazi Jews, was found at a frequency of 16.4% (10/61). There was one
novel mutation (4866insT) and one reported mutation in BRCA2. Thus, our study emphasizes the importance of mutation screening in familial breast and/or ovarian cancers, and the potential
implications of these findings in genetic counselling and preventive therapy. 相似文献