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排序方式: 共有604条查询结果,搜索用时 15 毫秒
1.
Vijayakumar Maheshwari Malathi Sushil K. Jalali Dandinashivara K. Sidde Gowda Muthugounder Mohan Thiruvengadam Venkatesan 《Insect Science》2017,24(1):35-46
The brown planthopper (BPH), Nilaparvata lugens (Stål), is one of the major pests of rice throughout Asia. Extensive use of insecticides for suppressing N. lugens has resulted in the development of insecticide resistance leading to frequent control failures in the field. The aim of the present study was to evaluate resistance in the field populations of N. lugens from major rice growing states of South India to various insecticides. We also determined the activity of detoxifying enzymes (esterases [ESTs], glutathione S‐transferases [GSTs], and mixed‐function oxidases [MFOs]). Moderate levels of resistance were detected in the field populations to acephate, thiamethoxam and buprofezin (resistance factors 1.05–20.92 fold, 4.52–14.99 fold, and 1.00–18.09 fold, respectively) as compared with susceptible strain while there were low levels of resistance to imidacloprid (resistance factor 1.23–6.70 fold) and complete sensitivity to etofenoprox (resistance factor 1.05–1.66 fold). EST activities in the field populations were 1.06 to 3.09 times higher than the susceptible strain while for GST and MFO the ratios varied from 1.29 to 3.41 and 1.03 to 1.76, respectively. The EST activity was found to be correlated to acephate resistance (r = 0.999, P ≥ 0.001). The high selection pressure of organophosphate, neonicotinoid, and insect growth regulator (IGR) in the field is likely to be contributing for resistance in BPH to multiple insecticides, leading to control failures. The results obtained will be beneficial to IPM recommendations for the use of effective insecticides against BPH. 相似文献
2.
Pratichi Singh Arthi Venkatesan Parasuraman Padmanabhan Balazs Gulyas Febin Prabhu Dass J 《Journal of cellular biochemistry》2020,121(1):534-544
Hepatitis C virus (HCV) infection is among the leading causes of hepatocellular carcinoma and liver cirrhosis globally, with a high economic burden. The disease progression is well established, but less is known about the spontaneous HCV infection clearance. This study tries to establish the relationship between codon biasness and expression of HCV clearance candidate genes in normal and HCV infected liver tissues. A total of 112 coding sequences comprising 151 679 codons were subjected to the computation of codon indices, namely relative synonymous codon usage, an effective number of codon (Nc), frequency of optimal codon, codon adaptation index, codon bias index, and base compositions. Codon indices report of GC3s, GC12, hydropathicity, and aromaticity implicates both mutational and translational selection in the candidate gene set. This was further correlated with the differentially expressed genes among the selected genes using BioGPS. A significant correlation is observed between the gene expression of normal liver and cancerous liver tissues with codon bias (Nc). Gene expression is also correlated with relative codon bias values, indicating that CCL5, APOA2, CD28, IFITM1, and TNFSF4 genes have higher expression. These results are quite encouraging in selecting the high responsive genes in HCV clearance. However, there could be additional genes which could also orchestrate the clearance role with the above mentioned first line of defensive genes. 相似文献
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Daniel I. Rubenstein Siva R. Sundaresan Ilya R. Fischhoff Chayant Tantipathananandh Tanya Y. Berger-Wolf 《PloS one》2015,10(10)
Understanding why animal societies take on the form that they do has benefited from insights gained by applying social network analysis to patterns of individual associations. Such analyses typically aggregate data over long time periods even though most selective forces that shape sociality have strong temporal elements. By explicitly incorporating the temporal signal in social interaction data we re-examine the network dynamics of the social systems of the evolutionarily closely-related Grevy’s zebras and wild asses that show broadly similar social organizations. By identifying dynamic communities, previously hidden differences emerge: Grevy’s zebras show more modularity than wild asses and in wild asses most communities consist of solitary individuals; and in Grevy’s zebras, lactating females show a greater propensity to switch communities than non-lactating females and males. Both patterns were missed by static network analyses and in general, adding a temporal dimension provides insights into differences associated with the size and persistence of communities as well as the frequency and synchrony of their formation. Dynamic network analysis provides insights into the functional significance of these social differences and highlights the way dynamic community analysis can be applied to other species. 相似文献
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Trishul Artham M. Sudhakar R. Venkatesan C. Madhavan Nair K.V.G.K. Murty Mukesh Doble 《International biodeterioration & biodegradation》2009,63(7):884-890
Commercial synthetic polymers namely Polycarbonate (PC), Low density polyethylene (LDPE), High density polyethylene (HDPE), and Polypropylene (PP) coupons were immersed for a period of 12 months (Feb 2006 – Feb 2007) in Bay of Bengal, East coast, India. Samples were retrieved every month and the extent of biofouling and biodegradation were monitored. Biofouling was found to depend not only on the season but also on the chemical nature of the polymer. Surface energy of all the four polymers is positively correlated with fouling only at the initial stages (three months) while surface roughness had a negative correlation. The later increased during the study period. Total suspended solids and organic matter were more abundant on HDPE, followed by PP and LDPE, indicating that among polyolefins hydrophobic surfaces (lower surface energy) favor biofouling over one year. Maximum fouling was observed on polycarbonate during initial three months. Chlorophyll a showed a decreasing trend during the study, as secondary foulers such as Balanus amphitrite, were dominant after the monsoon (6th month in the present study). Maximum weight loss was seen in LDPE (1.9%), followed by that in HDPE (1.6%), PC (0.69%) and finally in PP (0.65%) samples in the 12 months time period. FTIR spectra of PC displayed a decrease in carbonate carbonyl index, while an initial increase and a decrease in carbonyl index of polyolefins as a function of time indicated biodegradation. 相似文献
7.
M C Daly J B Douglas N M Bleehen P Hastleton P R Twentyman V Sundaresan B Carritt J Bergh P H Rabbitts 《Genomics》1991,9(1):113-119
The tumors of patients with small cell lung carcinoma (SCLC) frequently exhibit the loss of alleles at polymorphic loci on the short arm of chromosome 3. We report the genotype analysis of six SCLC patients obtained using 15 chromosome 3 probes that identified 19 restriction fragment length polymorphisms (RFLPs). Five of the six patients were reduced to homozygosity in the tumor DNA at every informative 3p locus, and thus did not serve to delineate the deletion. However, the RFLP analysis of the tumor DNA of the sixth patient demonstrated both heterozygous and hemizygous loci on 3p and allowed the definition of an interstitial deletion that extends proximal to the D3S2 locus at 3p14.2-p21 to include at least 3p13-p14. The exclusion of the D3F15S2 locus from the deleted region, observed in this patient, is an uncharacteristic feature of SCLC deletions. This deletion includes the location of D3S30 and D3S4, and thus serves to map these loci within the proximal half of chromosome 3. 相似文献
8.
Soundarya L. Madhira Satya S. Challa Maniprabha Chalasani Giridharan Nappanveethl Ramesh R. Bhonde Rajanna Ajumeera Vijayalakshmi Venkatesan 《PloS one》2012,7(10)
Background
Development of model systems have helped to a large extent, in bridging gap to understand the mechanism(s) of disease including diabetes. Interestingly, WNIN/GR-Ob rats (Mutants), established at National Centre for Laboratory Animals (NCLAS) of National Institute of Nutrition (NIN), form a suitable model system to study obesity with Type 2 diabetes (T2D) demonstrating several secondary complications (cataract, cardiovascular complications, infertility, nephropathy etc). The present study has been carried out to explore the potent application(s) of multipotent stem cells such as bone marrow mesenchymal stem cells (BM-MSCs), to portray features of pre-diabetic/T2D vis-à-vis featuring obesity, with impaired glucose tolerance (IGT), hyperinsulinemia (HI) and insulin resistance (IR) seen with Mutant rats akin to human situation.Methodology/Principal Findings
Primary cultures of BM-MSCs (third passage) from Mutants, its lean littermate (Lean) and parental control (Control) were characterized for: proliferation markers, disease memory to mark obesity/T2D/HI/IR which included phased gene expression studies for adipogenic/pancreatic lineages, inflammatory markers and differentiation ability to form mature adipocytes/Insulin-like cellular aggregates (ILCAs). The data showed that BM-MSCs from Mutant demonstrated a state of disease memory, depicted by an upregulated expression of inflammatory markers (IL-6, TNFα); increased stem cell recruitment (Oct-4, Sox-2) and proliferation rates (CD90+/CD29+, PDA, ‘S’ phase of cell cycle by FACS and BrdU incorporation); accelerated preadipocyte induction (Dact-1, PPARγ2) with a quantitative increase in mature adipocyte formation (Leptin); ILCAs, which were non-responsive to high glucose did confer the Obese/T2D memory in Mutants. Further, these observations were in compliance with the anthropometric data.Conclusions
Given the ease of accessibility and availability of MSCs, the present study form the basis to report for the first time, application of BM-MSCs as a feasible in vitro model system to portray the disease memory of pre-clinical/T2D with IR - a major metabolic disorder of global concern. 相似文献9.
Kusampudi Shilpa Kadapakkam Nandabalan Sangeetha Velusamy Shanmuganathan Muthusamy Sundaresan Sujatha Baddireddi Subadhra Lakshmi 《Biotechnology letters》2009,31(12):1837-1841
A methanolic extract of Costus pictus (CPME) showed optimum anti-diabetic activity at 100 ng/ml. Bioactivity-guided purification of CPME led to the isolation of
methyl tetracosanoate (MT) which showed an optimum glucose uptake at 1 ng/ml. CPME at 10 μg/ml inhibited adipogenesis whereas
fully differentiated adipocytes exhibited a 3-fold increase in lipid accumulation compared to pre-adipocytes. Gene and protein
expression of key targets in insulin signaling and adipogenesis pathway revealed that CPME exhibited anti-diabetic activity
along with anti-adipogenic activity whereas MT demonstrated only anti-diabetic activity. 相似文献
10.