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121.
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
122.
We have determined the non-synonymous single-nucleotide polymorphisms (nsSNPs) of ?? adducin 1 (ADD1) gene and its variations in different populations to understand its role in hypertension. Out of 1,113 SNPs, 9 are found to be non-synonymous, of which 7 showed significant damaging effect and one of them showed SNP variability with large differences among the minor allele frequency observed in various populations. The amino acid change found for rs4961 is from glycine to tryptophan, i.e., from an alkyl amino acid to an aromatic amino acid. This residual change is observed in the coiled region of the protein and is also predicted to be disordered by computational algorithm. Protein disorder plays an important role in structural and functional genomics. Hence, because of the complete change in side chains of the amino acid residues occurring in the coiled and disordered region of the protein, the structure of the protein might be altered and the function might be affected, leading to the risk for hypertension. 相似文献
123.
Sini Thomas Anjali Anand Viswanthan Chinnusamy Anil Dahuja Sudipta Basu 《Acta Physiologiae Plantarum》2013,35(12):3401-3411
Chickpea seeds of Pusa 1053 (Mediterranean) and Pusa 256 (native) were magnetoprimed with 100 mT static magnetic field for 1 h to evaluate the effect of magnetopriming on germination of seeds under saline conditions. Enhanced rate of germination and seedling growth parameters (root and shoot length, and vigour indices) under different salinity levels indicated that magnetopriming was more effective in alleviating salinity stress at early seedling stage in Pusa 1053 as compared to Pusa 256. Dynamics of seed water absorption in magnetoprimed seeds showed increased water uptake in Pusa 1053 under non-saline as compared to saline conditions. This could have resulted in faster hydration of enzymes in primed seeds leading to higher rate of germination. Total amylase, protease and dehydrogenase activities were higher in primed seeds as compared to unprimed seeds under both non-saline and saline conditions. Production of superoxide radicals was enhanced in germinating seeds of both the genotypes under salinity irrespective of priming. Increased levels of hydrogen peroxide in germinating magnetoprimed seeds, under both the growing conditions, suggested its role in promotion of germination. Our results showed that magnetopriming of dry seeds of chickpea can be effectively used as a pre-sowing treatment for mitigating adverse effects of salinity at seed germination and early seedling growth. 相似文献
124.
DG指数在定量多样性时的缺陷及其内涵解析 总被引:2,自引:0,他引:2
生物多样性通常使用物种丰富度、Simpson指数、Shannon-Wiener多样性指数等来进行度量, 但是在土壤动物群落研究中, 由于使用了粗水平的分类方法, 因此即使生境变化很大, 这些多样性指数在评估群落多样性变化时仍然是不适当的。为了克服这种限制, 廖崇惠(1990, 2009)提出用DG指数来代替这些标准的多样性指数, 并在土壤动物生态学领域得到了广泛应用。然而笔者分析发现DG指数与Pielou均匀度指数呈显著的负相关关系(r = –0.534, P = 0.000), 即, 高的均匀度反而有低的多样性。另外, DG指数与类群数(r = 0.648, P = 0.000)和类群密度(r = 0.487, P = 0.000)呈明显的正相关, 类群数的下降可以通过部分类群密度的上升而获得补偿, 群落的类群丢失后却可以获得一个不变的甚至更高的多样性值。因此, 笔者不支持DG指数用于测度生物多样性, 提议使用各类群实际群势与潜在群势比值的平均值来估计群落潜在多度的实现程度。如果继续使用DG指数作为实际生境条件的一个指标, 那么与以往不同, DG指数测度的是该生境群落多度增长的一种潜力。 相似文献
125.
Hill BC Becker L Anand V Kusmierczyk A Marcovina SM Rahman MN Gabel BR Jia Z Boffa MB Koschinsky ML 《Archives of biochemistry and biophysics》2003,412(2):186-195
Low-density lipoprotein (LDL) oxidation is stimulated by copper. Addition of a recombinant form of apolipoprotein(a) (apo(a); the distinguishing protein component of lipoprotein(a)) containing 17 plasminogen kringle IV-like domains (17K r-apo(a)) protects LDL against oxidation by copper. Protection is specific to apo(a) and is not achieved by plasminogen or serum albumin. When Cu(2+) is added to 17K r-apo(a), its intrinsic fluorescence is quenched in a concentration-dependent and saturable manner. Quenching is unchanged whether performed aerobically or anaerobically and is reversible by ethylenediaminetetraacetate, suggesting that it is due to equilibrium binding of Cu(2+) and not to oxidative destruction of tryptophan residues. The fluorescence change exhibits a sigmoid dependence on copper concentration, and time courses of quenching are complex. At copper concentrations below 10 microM there is little quenching, whereas above 10 microM quenching proceeds immediately as a double-exponential decay. The affinity and kinetics of copper binding to 17K r-apo(a) are diminished in the presence of the lysine analogue epsilon -aminocaproic acid. We propose that copper binding to the kringle domains of 17K is mediated by a His-X-His sequence that is located about 5A from the closest tryptophan residue of the lysine binding pocket. Copper binding may account for the natural resistance to copper-mediated oxidation of lipoprotein(a) relative to LDL that has been previously reported and for the protection afforded by apo(a) from copper-mediated oxidation of LDL that we describe in the present study. 相似文献
126.
1,3-Propanediol, a valuable bifunctional molecule, can be produced from renewable resources using microorganisms. It has several promising properties for many synthetic reactions, particularly for polymer and cosmetic industries. By virtue of being a natural product, relevant biochemical pathways can be harnessed into fermentation processes to produce 1,3-propanediol. Various strategies for the microbial production of 1,3-propanediol are reviewed and compared in this article with their promises and constraints. Furthermore, genetic and metabolic engineering could significantly improve product yields and overcome the limitations of fermentation technology. Present review gives an overview on 1,3-propanediol production by wild and recombinant strains. It also attempts to encompass the various issues concerned in utilization of crude glycerol for 1,3-propanediol production, with particular emphasis laid on biodiesel industries. This review also summarizes the present state of strategies studied for the downstream processing and purification of biologically produced 1,3-propanediol. The future prospect of 1,3-propanediol and its potential as a major bulk chemical are discussed under the light of the current research. 相似文献
127.
Rinki Ratnapriya Parthasarthy Satishchandra S. Dilip Kumar Girish Gadre Ramesh Reddy Anuranjan Anand 《Human genetics》2009,125(5-6):541-549
Hot water epilepsy (HWE) is a form of reflex or sensory epilepsy wherein seizures are precipitated by an unusual stimulus, the contact of hot water over the head and body. Genome-wide linkage analysis of a large family with ten affected members, provided evidence of linkage (Z max = 3.17 at θ = 0 for D10S412) to chromosome 10q21. Analysis of five additional HWE families, for markers on chromosome 10, further strengthened the evidence of linkage to the same chromosomal region with three out of five families showing concordance for the disease haplotype and providing a two-point LOD score of 4.86 at θ = 0 and 60% penetrance for D10S412. The centromere-proximal and -distal boundaries of the critical genetic interval of about 15 Mb at 10q21.3-q22.3 were defined by D10S581 and D10S201, respectively. Sequence analysis of a group of functional candidate genes, the ion channels KCNMA1, VDAC2 and solute carriers SLC25A16, SLC29A3 revealed no potentially pathogenic mutation. We propose to carry out further analysis of positional candidate genes from this region to identify the gene responsible for this unusual neurobehavioral phenotype. 相似文献
128.
Lijuan Sun Sanjay Verma Navin Michael Siew Pang Chan Jianhua Yan Suresh Anand Sadananthan Stefan G. Camps Hui Jen Goh Priya Govindharajulu John Totman David Townsend Julian Pak‐Nam Goh Lei Sun Bernhard Otto Boehm Su Chi Lim Siew Kwan Sze Christiani Jeyakumar Henry Houchun Harry Hu S. Sendhil Velan Melvin Khee‐Shing Leow 《Obesity (Silver Spring, Md.)》2019,27(9):1434-1442
129.
Nam P. Nguyen Lexie Smith-Raymond Vincent Vinh-Hung Paul Vos Rick Davis Anand Desai Thomas Sroka Dave Abraham Shane P. Krafft Michelle Stevie Homayoun Modarresifar Beng-Hoey Jo Misty Ceizyk 《PloS one》2013,8(3)
Purpose
The study aims to assess the feasibility of Tomotherapy-based image-guided radiotherapy (IGRT) to reduce the aspiration risk in patients with non-laryngeal and non-hypopharyngeal cancer. A retrospective review of 48 patients undergoing radiation for non-laryngeal and non-hypopharyngeal head and neck cancers was conducted. All patients had a modified barium swallow (MBS) prior to treatment, which was repeated one month following radiotherapy. Mean middle and inferior pharyngeal dose was recorded and correlated with the MBS results to determine aspiration risk.Results
Mean pharyngeal dose was 23.2 Gy for the whole group. Two patients (4.2%) developed trace aspiration following radiotherapy which resolved with swallowing therapy. At a median follow-up of 19 months (1–48 months), all patients were able to resume normal oral feeding without aspiration.Conclusion and Clinical Relevance
IGRT may reduce the aspiration risk by decreasing the mean pharyngeal dose in the presence of large cervical lymph nodes. Further prospective studies with IGRT should be performed in patients with non-laryngeal and non-hypopharyngeal head and neck cancers to verify this hypothesis. 相似文献130.
Satoi Nagasawa Anna S. Sedukhina Yuko Nakagawa Ichiro Maeda Manabu Kubota Shigeko Ohnuma Koichiro Tsugawa Tomohiko Ohta Marta Roche-Molina Juan A. Bernal Ana J. Narváez Anand D. Jeyasekharan Ko Sato 《PloS one》2015,10(2)
LSD1, a lysine-specific histone demethylase, is overexpressed in several types of cancers and linked to poor outcomes. In breast cancer, the significance of LSD1 overexpression is not clear. We have performed an in silico analysis to assess the relationship of LSD1 expression to clinical outcome. We demonstrate that LSD1 overexpression is a poor prognostic factor in breast cancer, especially in basal-like breast cancer, a subtype of breast cancer with aggressive clinical features. This link is also observed in samples of triple negative breast cancer. Interestingly, we note that overexpression of LSD1 correlates with down-regulation of BRCA1 in triple negative breast cancer. This phenomenon is also observed in in vitro models of basal-like breast cancer, and is associated with an increased sensitivity to PARP inhibitors. We propose therefore that high expression levels of the demethylase LSD1 is a potential prognostic factor of poor outcome in basal-like breast cancer, and that PARP inhibition may be a therapeutic strategy of interest in this poor prognostic subtype with overexpression of LSD1. 相似文献