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941.
Cheonik Joo Eeda Venkateswararao Ki-Cheul Lee Vinay K. Sharma Min-Sik Kyung Youngsoo Kim Sang-Hun Jung 《Bioorganic & medicinal chemistry》2012,20(19):5757-5762
Hydroxyethylaminomethyl-4H-chromenones were previously discovered as fairly strong IL-5 inhibitor. For determination of detail structure activity relationship, N-substituted hydroxyethylaminomethylchromenones 4a–n were prepared and evaluated for their IL-5 inhibitory activity. Shifting the hydrophobic group to nitrogen from 1-position of hydroxyethylamino moiety of hydroxyethylaminomethyl-4H-chromenones enhances the activity. The increment in bulkiness or hydrophobicity of alkyl side chain at amino group increases the activity. The same level of activity of 5-(cyclohexylmethoxy)-3-(N-benzyl-2-hydroxyethylaminomethyl)-4H-chromenone analogs regardless of hydrophobic or hydrophilic substituents at 4th position of phenyl ring might infer the existence of tunnel structure in the putative receptor for accepting these side chains. 相似文献
942.
Gautam Sharma Nagendra Boopathy Senguttuvan Sandeep Singh Rajnish Juneja Vinay K Bahl 《Indian pacing and electrophysiology journal》2012,12(6):274-277
Central venous stenosis after the insertion of a permanent pacemaker is a well recognized complication. This late complication is encountered when there is a need to change the pacemaker lead or extract it. We describe a young male who had such a complication after many years after right side pacemaker implantation. The lesion was managed percutaneously leading to placement of a new lead from the left side. 相似文献
943.
BACKGROUND:
Recombination (crossing over) may generate novel haplotypes that can be beneficial to a population against recently introduced pathogens. It may lead to the generation of new alleles.SETTINGS AND DESIGN:
A prospective study at a tertiary care centre.AIM:
To report two rare cases of crossing over in HLA region.MATERIALS AND METHODS:
Tissue-typing was done by sequence specific primers (SSP) for DR locus and by both SSP and serology for Class I which was reconfirmed on fresh samples.RESULTS:
In one patient crossing over had taken place in the region of A locus resulting in inheritance of A*01 instead of expected A*11. In second family crossing over had taken place in region of DRB1 locus and the sibling inherited DRB1*08 instead of DRB1*10.CONCLUSIONS:
Possibility of recombination must be considered when interpreting implausible tissue-typing results of families worked up for BMT. 相似文献944.
Ectomycorrhizal (ECM) fungal species, a "Symbiotic" relationship between tress and fungi in forest has a great ecological and economic importance. Here is an attempt to describe database named "EctomycorrhizalDB", addressing ECM diversity of Central Himalaya (Kumaun region), with special emphasis on their characterization, physical properties and morphological features along with specifications. This database would help the scientific community to draw a better understanding of the environmental factors that affects species diversity. AVAILABILITY: The database is available for free at http://www.kubic.nic.in/ectomychorhiza. 相似文献
945.
Shrinet J Jain S Sharma A Singh SS Mathur K Rana V Bhatnagar RK Gupta B Gaind R Deb M Sunil S 《Virology journal》2012,9(1):100-8
ABSTRACT: BACKGROUND: Chikungunya (CHIK) is currently endemic in South and Central India and exist as co-infections with dengue in Northern India. In 2010, New Delhi witnessed an outbreak of CHIK in the months October-December. This was the first incidence of a dominant CHIK outbreak in Delhi and prompted us to characterize the Delhi virus strains. We have also investigated the evolution of CHIK spread in India. FINDINGS: Clinical samples were subjected to RT-PCR to detect CHIK viral RNA. The PCR amplified products were sequenced and the resulting sequences were genetically analyzed. Phylogenetic analysis based on partial sequences of the structural proteins E1 and E2 revealed that the viruses in the latest outbreak exhibited ECSA lineage. Two novel mutations, E1 K211E and E2 V264A were observed in all Delhi isolates. In addition, CHIKV sequences from eight states in India were analyzed along with Delhi sequences to map the genetic diversity of CHIKV within the country. Estimates of average evolutionary divergence within states showed varying divergence among the sequences both within the states and between the states. We identified distinct molecular signatures of the different genotypes of CHIKV revealing emergence of a new signature in the New Delhi clade. Statistical analyses and construction of evolutionary path of the virus within the country revealed gradual spread of one specific strain all over the country. CONCLUSION: This study has identified unique mutations in the E1 and E2 genes and has revealed the presence of ancestral CHIKV population with maximum diversity circulating in Maharashtra. The study has further revealed the trend of CHIK spread in India since its first report in 1963 and its subsequent reappearance in 2005. 相似文献
946.
Haemophilus influenzae and Helicobacter pylori are major bacterial pathogens that face high levels of genotoxic stress within their host. UvrD, a ubiquitous bacterial helicase that plays important roles in multiple DNA metabolic pathways, is essential for genome stability and might, therefore, be crucial in bacterial physiology and pathogenesis. In this study, the functional characterization of UvrD helicase from Haemophilus influenzae and Helicobacter pylori is reported. UvrD from Haemophilus influenzae (HiUvrD) and Helicobacter pylori (HpUvrD) exhibit strong single-stranded DNA-specific ATPase and 3'-5' helicase activities. Mutation of highly conserved arginine (R288) in HiUvrD and glutamate (E206) in HpUvrD abrogated their activities. Both the proteins were able to bind and unwind a variety of DNA structures including duplexes with strand discontinuities and branches, three- and four-way junctions that underpin their role in DNA replication, repair and recombination. HiUvrD required a minimum of 12 nucleotides, whereas HpUvrD preferred 20 or more nucleotides of 3'-single-stranded DNA tail for efficient unwinding of duplex DNA. Interestingly, HpUvrD was able to hydrolyze and utilize GTP for its helicase activity although not as effectively as ATP, which has not been reported to date for UvrD characterized from other organisms. HiUvrD and HpUvrD were found to exist predominantly as monomers in solution together with multimeric forms. Noticeably, deletion of distal C-terminal 48 amino acid residues disrupted the oligomerization of HiUvrD, whereas deletion of 63 amino acids from C-terminus of HpUvrD had no effect on its oligomerization. This study presents the characteristic features and comparative analysis of Haemophilus influenzae and Helicobacter pylori UvrD, and constitutes the basis for understanding the role of UvrD in the biology and virulence of these pathogens. 相似文献
947.
Sharma S Sandhu KS Bal MS Kumar H Verma S Dubey JP 《The Journal of parasitology》2008,94(5):1174-1175
Sera from 186 sheep, 83 cattle, and 103 water buffaloes from Punjab, India, were evaluated for antibodies to Toxoplasma gondii using a commercial ELISA kit. This study was planned using a 2-stage random sampling procedure and sampling software 'survey toolbox.' In the first step, villages were selected randomly from a sampling frame of all the villages of Punjab, followed by selection of owners and animals in the second step. Antibodies to T. gondii were found in 7 of 186 sheep, 2 of 83 cattle, and 3 of 103 buffaloes. Results indicate a low prevalence of T. gondii in ruminants tested. 相似文献
948.
Vyas N Goswami D Manonmani A Sharma P Ranganath HA VijayRaghavan K Shashidhara LS Sowdhamini R Mayor S 《Cell》2008,133(7):1214-1227
Hedgehog (Hh) plays crucial roles in tissue-patterning and activates signaling in Patched (Ptc)-expressing cells. Paracrine signaling requires release and transport over many cell diameters away by a process that requires interaction with heparan sulfate proteoglycans (HSPGs). Here, we examine the organization of functional, fluorescently tagged variants in living cells by using optical imaging, FRET microscopy, and mutational studies guided by bioinformatics prediction. We find that cell-surface Hh forms suboptical oligomers, further concentrated in visible clusters colocalized with HSPGs. Mutation of a conserved Lys in a predicted Hh-protomer interaction interface results in an autocrine signaling-competent Hh isoform--incapable of forming dense nanoscale oligomers, interacting with HSPGs, or paracrine signaling. Thus, Hh exhibits a hierarchical organization from the nanoscale to visible clusters with distinct functions. 相似文献
949.
Lee HS Wang Y Maciejewski BS Esho K Fulton C Sharma S Sanchez-Esteban J 《American journal of physiology. Lung cellular and molecular physiology》2008,294(2):L225-L232
Mechanical ventilation plays a central role in the pathogenesis of bronchopulmonary dysplasia. However, the mechanisms by which excessive stretch of fetal or neonatal type II epithelial cells contributes to lung injury are not well defined. In these investigations, isolated embryonic day 19 fetal rat type II epithelial cells were cultured on substrates coated with fibronectin and exposed to 5% or 20% cyclic stretch to simulate mechanical forces during lung development or lung injury, respectively. Twenty percent stretch of fetal type II epithelial cells increased necrosis, apoptosis, and proliferation compared with control, unstretched samples. By ELISA and real-time PCR (qRT-PCR), 20% stretch increased secretion of IL-8 into the media and IL-8 gene expression and inhibited IL-10 release. Interestingly, administration of recombinant IL-10 before 20% stretch did not affect cell lysis but significantly reduced apoptosis and IL-8 release compared with stretched samples without IL-10. Collectively, our studies suggest that IL-10 may play an important role in protection of fetal type II epithelial cells from injury secondary to stretch. 相似文献
950.
R T Venkatachalapathy Arjava Sharma Soumi Sukla Tarun K Bhattacharya 《DNA sequence》2008,19(3):177-184
The present study was carried out to characterize the DGAT1 gene of Riverine buffalo. Total RNA was extracted from the mammary tissue of buffalo and DGAT1cDNA were synthesized by RT-PCR, then cloned using pDRIVE cloning vector and sequenced. The sequencing revealed that the size of DGAT1 gene was 1470 bp with GC content of 62.30%. The gene encoded for 489 amino acid precursors and that it possessed 32 amino acids signal peptide. The similarity of buffalo DGAT1 mRNA sequence with that of cattle, pig, monkey, human, mice and rat were determined as 98.4, 90.7, 85.4, 85.0, 77.4 and 77.1%, respectively. Phylogenetic tree constructed from the derived DGAT1 protein sequences of 15 different species illustrated a unique branches for mammals, fly, nematode and plants. Among mammals, cattle and buffalo grouped together, whereas swine formed another group in the same branch. Four motifs were predicted in buffalo DGAT1 peptide sequence, one N-linked glycosylation site (246th position), two putative tyrosine phosphorylation site (316 and 261), one putative diacylglycerol binding site (382-392 amino acid position) and a conserved domain MBOAT (membrane bound acyl transferase from 150 to 474 amino acids) with a histidine as an active residue. 相似文献