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141.
Aminedi Raghavendra Dhatwalia Deepa Jain Varsha Bhattacharya Ramcharan 《Plant Cell, Tissue and Organ Culture》2019,138(2):229-237
Plant Cell, Tissue and Organ Culture (PCTOC) - Brassica juncea (Indian mustard) and its sub-varieties include whole range of oilseed and vegetable mustard in China, Canada, Australia, Europe and... 相似文献
142.
Varsha J. Thombare James A. Holden Eric C. Reynolds Neil M. O'Brien‐Simpson Craig A. Hutton 《Journal of peptide science》2020,26(3)
Bicyclic analogues of celogentin C have been synthesized in which the side chain–side chain cross‐links are replaced by thioether bonds. Several of the simplified bicyclic peptides displayed potent inhibition of tubulin polymerization. 相似文献
143.
Rashmi Lakshminarayana Alex Eble Preetha Bhakta Chris Frost Peter Boone Diana Elbourne Vera Mann 《PloS one》2013,8(7)
Background
The aim of the STRIPES trial was to assess the effectiveness of providing supplementary, remedial teaching and learning materials (and an additional ‘kit’ of materials for girls) on a composite of language and mathematics test scores for children in classes two, three and four in public primary schools in villages in the Nagarkurnool division of Andhra Pradesh, India.Methods
STRIPES was a cluster randomised trial in which 214 villages were allocated either to the supplementary teaching intervention (n = 107) or to serve as controls (n = 107). 54 of the intervention villages were further randomly allocated to receive additional kit for girls. The study was not blinded. Analysis was conducted on the intention to treat principle, allowing for clustering.Results
Composite test scores were significantly higher in the intervention group (107 villages; 2364 children) than in the control group (106 villages; 2014 children) at the end of the trial (mean difference on a percentage scale 15.8; 95% CI 13.1 to 18.6; p<0.001; 0.75 Standard Deviation (SD) difference). Composite test scores were not significantly different in the 54 villages (614 girls) with the additional kits for girls compared to the 53 villages (636 girls) without these kits at the end of the trial (mean difference on a percentage scale 0.5; 95% CI -4.34 to 5.4; p = 0.84). The cost per 0.1 SD increase in composite test score for intervention without kits is Rs. 382.97 (£4.45, $7.13), and Rs.480.59 (£5.58, $8.94) for the intervention with kits.Conclusions
A 18 month programme of supplementary remedial teaching and learning materials had a substantial impact on language and mathematics scores of primary school students in rural Andhra Pradesh, yet providing a ‘kit’ of materials to girls in these villages did not lead to any measured additional benefit.Trial Registration
Controlled-Trials.com ISRCTN69951502 相似文献144.
High density genetic maps are a reliable tool for genetic dissection of complex plant traits. Mapping resolution is often hampered by the variable crossover and non-crossover events occurring across the genome, with pericentromeric regions (pCENR) showing highly suppressed recombination rates. The efficiency of linkage mapping can further be improved by characterizing and understanding the distribution of recombinational activity along individual chromosomes. In order to evaluate the genome wide recombination rate in common beans (Phaseolus vulgaris L.) we developed a SNP-based linkage map using the genotype-by-sequencing approach with a 188 recombinant inbred line family generated from an inter gene pool cross (Andean x Mesoamerican). We identified 1,112 SNPs that were subsequently used to construct a robust linkage map with 11 groups, comprising 513 recombinationally unique marker loci spanning 943 cM (LOD 3.0). Comparative analysis showed that the linkage map spanned >95% of the physical map, indicating that the map is almost saturated. Evaluation of genome-wide recombination rate indicated that at least 45% of the genome is highly recombinationally suppressed, and allowed us to estimate locations of pCENRs. We observed an average recombination rate of 0.25 cM/Mb in pCENRs as compared to the rest of genome that showed 3.72 cM/Mb. However, several hot spots of recombination were also detected with recombination rates reaching as high as 34 cM/Mb. Hotspots were mostly found towards the end of chromosomes, which also happened to be gene-rich regions. Analyzing relationships between linkage and physical map indicated a punctuated distribution of recombinational hot spots across the genome. 相似文献
145.
146.
Sorajja D Bhakta MD Scott LR Altemose GT Srivathsan K 《Indian pacing and electrophysiology journal》2010,10(9):383-392
Background
Empiric programming of the atrio-ventricular (AV) delay is commonly performed during pacemaker implantation. Transmitral flow assessment by Doppler echocardiography can be used to find the optimal AV delay by Ritter''s method, but this cannot easily be performed during pacemaker implantation. We sought to determine a non-invasive surrogate for this assessment. Since electrocardiographic P-wave duration estimates atrial activation time, we hypothesized this measurement may provide a more appropriate basis for programming AV intervals.Methods
A total of 19 patients were examined at the time of dual chamber pacemaker implantation, 13 (68%) being male with a mean age of 77. Each patient had the optimal AV interval determined by Ritter''s method. The P-wave duration was measured independently on electrocardiograms using MUSE® Cardiology Information System (version 7.1.1). The relationship between P-wave duration and the optimal AV interval was analyzed.Results
The P-wave duration and optimal AV delay were related by a correlation coefficient of 0.815 and a correction factor of 1.26. The mean BMI was 27. The presence of hypertension, atrial fibrillation, and valvular heart disease was 13 (68%), 3 (16%), and 2 (11%) respectively. Mean echocardiographic parameters included an ejection fraction of 58%, left atrial index of 32 ml/m2, and diastolic dysfunction grade 1 (out of 4).Conclusions
In patients with dual chamber pacemakers in AV sequentially paced mode and normal EF, electrocardiographic P-wave duration correlates to the optimal AV delay by Ritter''s method by a factor of 1.26. 相似文献147.
Joshua C. Kwekel Varsha G. Desai Carrie L. Moland Vikrant Vijay James C. Fuscoe 《PloS one》2013,8(10)
Age is a predisposing condition for susceptibility to chronic kidney disease and progression as well as acute kidney injury that may arise due to the adverse effects of some drugs. Age-related differences in kidney biology, therefore, are a key concern in understanding drug safety and disease progression. We hypothesize that the underlying suite of genes expressed in the kidney at various life cycle stages will impact susceptibility to adverse drug reactions. Therefore, establishing changes in baseline expression data between these life stages is the first and necessary step in evaluating this hypothesis. Untreated male F344 rats were sacrificed at 2, 5, 6, 8, 15, 21, 78, and 104 weeks of age. Kidneys were collected for histology and gene expression analysis. Agilent whole-genome rat microarrays were used to query global expression profiles. An ANOVA (p<0.01) coupled with a fold-change>1.5 in relative mRNA expression, was used to identify 3,724 unique differentially expressed genes (DEGs). Principal component analyses of these DEGs revealed three major divisions in life-cycle renal gene expression. K-means cluster analysis identified several groups of genes that shared age-specific patterns of expression. Pathway analysis of these gene groups revealed age-specific gene networks and functions related to renal function and aging, including extracellular matrix turnover, immune cell response, and renal tubular injury. Large age-related changes in expression were also demonstrated for the genes that code for qualified renal injury biomarkers KIM-1, Clu, and Tff3. These results suggest specific groups of genes that may underlie age-specific susceptibilities to adverse drug reactions and disease. This analysis of the basal gene expression patterns of renal genes throughout the life cycle of the rat will improve the use of current and future renal biomarkers and inform our assessments of kidney injury and disease. 相似文献
148.
Diversity of the human immunodeficiency virus type 1 (HIV-1) env sequence after vertical transmission in mother-child pairs infected with HIV-1 subtype A 下载免费PDF全文
Verhofstede C Demecheleer E De Cabooter N Gaillard P Mwanyumba F Claeys P Chohan V Mandaliya K Temmerman M Plum J 《Journal of virology》2003,77(5):3050-3057
Although several virologic and immunologic factors associated with an increased risk of perinatal human immunodeficiency virus type 1 (HIV-1) transmission have been described, the mechanism of mother-to-child transmission is still unclear. More specifically, the question of whether selective pressures influence the transmission remains unanswered. The aim of this study was to assess the genetic diversity of the transmitted virus after in utero transmission and after peripartum transmission and to compare the viral heterogeneity in the child with the viral heterogeneity in the mother. To allow a very accurate characterization of the viral heterogeneity in a single sample, limiting-dilution sequencing of a 1016-bp fragment of the env gene was performed. Thirteen children were tested, including 6 with in utero infections and 7 with peripartum infections. Samples were taken the day after birth and at the ages of 6 and 14 weeks. A homogeneous virus population was seen in six (46.2%) infants, of whom two were infected in utero and four were infected peripartum. A more heterogeneous virus population was detected in seven infants (53.8%), four infected in utero and three infected peripartum. The phylogenetic trees of the mother-child pairs presented a whole range of different tree topologies and showed infection of the child by one or more maternal variants. In conclusion, after HIV-1 transmission from mother to child a heterogeneous virus population was detected in approximately one-half of the children examined. Heterogeneous virus populations were found after peripartum infection as well as after in utero infection. Phylogenetic tree topologies argue against selection processes as the major mechanism driving mother-to-child transmission but support the hypothesis that virus variability is mainly driven by the inoculum level and/or exposure time. 相似文献
149.
Bhakta NR Garcia AM Frank EH Grodzinsky AJ Morales TI 《The Journal of biological chemistry》2000,275(8):5860-5866
Bovine articular cartilage discs (3 mm diameter x 400 micrometer thick) were equilibrated in buffer containing (125)I-insulin-like growth factor (IGF)-I (4 degrees C) +/- unlabeled IGF-I or IGF-II. Competition for binding to cartilage discs by each unlabeled IGF was concentration-dependent, with ED(50) values for inhibition of (125)I-IGF-I binding of 11 and 10 nM for IGF-I and -II, respectively, and saturation by 50 nM. By contrast, an analog of IGF-I with very low affinity for the insulin-like growth factor-binding proteins (IGF-BPs), des-(1-3)-IGF-I, was not competitive with (125)I-IGF-I for cartilage binding even at 100-400 nM. Binding of the (125)I-labeled IGF-II isoform to cartilage was competed for by unlabeled IGF-I or -II, with ED(50)s of 160 and 8 nM, respectively. This probably reflected the differential affinities of the endogenous IGF-BPs (IGF-BP-6 and -2) for IGF-II/IGF-I. Transport of (125)I-IGF-I was also measured in an apparatus that allows diffusion only across the discs (400 micrometer), by addition to one side and continuous monitoring of efflux on the other side. The time lag for transport of (125)I-IGF was 266 min, an order of magnitude longer than the theoretical prediction for free diffusion in the matrix. (125)I-IGF-I transport then reached a steady state rate (% efflux of total added (125)I-IGF/unit time), which was subsequently accelerated approximately 2-fold by addition of an excess of unlabeled IGF-I. Taken together, these results indicate that IGF binding to cartilage, mostly through the IGF-BPs, regulates the transport of IGFs in articular cartilage, probably contributing to the control of their paracrine activities. 相似文献
150.
Ya-Li Zheng Niranjana D. Amin Ya-Fang Hu Parvathi Rudrabhatla Varsha Shukla Jyotshnabala Kanungo Sashi Kesavapany Philip Grant Wayne Albers Harish C. Pant 《The Journal of biological chemistry》2010,285(44):34202-34212
The activity of Cdk5-p35 is tightly regulated in the developing and mature nervous system. Stress-induced cleavage of the activator p35 to p25 and a p10 N-terminal domain induces deregulated Cdk5 hyperactivity and perikaryal aggregations of hyperphosphorylated Tau and neurofilaments, pathogenic hallmarks in neurodegenerative diseases, such as Alzheimer disease and amyotrophic lateral sclerosis, respectively. Previously, we identified a 125-residue truncated fragment of p35 called CIP that effectively and specifically inhibited Cdk5-p25 activity and Tau hyperphosphorylation induced by Aβ peptides in vitro, in HEK293 cells, and in neuronal cells. Although these results offer a possible therapeutic approach to those neurodegenerative diseases assumed to derive from Cdk5-p25 hyperactivity and/or Aβ induced pathology, CIP is too large for successful therapeutic regimens. To identify a smaller, more effective peptide, in this study we prepared a 24-residue peptide, p5, spanning CIP residues Lys245–Ala277. p5 more effectively inhibited Cdk5-p25 activity than did CIP in vitro. In neuron cells, p5 inhibited deregulated Cdk5-p25 activity but had no effect on the activity of endogenous Cdk5-p35 or on any related endogenous cyclin-dependent kinases in HEK293 cells. Specificity of p5 inhibition in cortical neurons may depend on the p10 domain in p35, which is absent in p25. Furthermore, we have demonstrated that p5 reduced Aβ(1–42)-induced Tau hyperphosphorylation and apoptosis in cortical neurons. These results suggest that p5 peptide may be a unique and useful candidate for therapeutic studies of certain neurodegenerative diseases. 相似文献