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141.
Seley Gharanei Anna T Brini Sumathi Vaiyapuri Abdullah Alholle Ashraf Dallol Elena Arrigoni Takeshi Kishida Toru Hiruma Smadar Avigad Robert Grimer Eamonn R Maher Farida Latif 《Epigenetics》2013,8(9):893-898
Ras-association domain family of genes consist of 10 members (RASSF1-RASSF10), all containing a Ras-association (RA) domain in either the C- or the N-terminus. Several members of this gene family are frequently methylated in common sporadic cancers; however, the role of the RASSF gene family in rare types of cancers, such as bone cancer, has remained largely uninvestigated. In this report, we investigated the methylation status of RASSF1A and RASSF2 in Ewing sarcoma (ES). Quantitative real-time methylation analysis (MethyLight) demonstrated that both genes were frequently methylated in Ewing sarcoma tumors (52.5% and 42.5%, respectively) as well as in ES cell lines and gene expression was upregulated in methylated cell lines after treatment with 5-aza-2′-deoxcytidine. Overexpression of either RASSF1A or RASSF2 reduced colony formation ability of ES cells. RASSF2 methylation correlated with poor overall survival (p = 0.028) and this association was more pronounced in patients under the age of 18 y (p = 0.002). These results suggest that both RASSF1A and RASSF2 are novel epigenetically inactivated tumor suppressor genes in Ewing sarcoma and RASSF2 methylation may have prognostic implications for ES patients. 相似文献
142.
Naïma Kaci-Ouchfoun Djamila Izemrane Abdelkrim Boudrissa Thérèse Gernigon Farida Khammar Jean Marie Exbrayat 《Theriogenology》2013
During the breeding season, a major androgen-dependent protein with an apparent molecular weight of 21 kDa was isolated and purified from the seminal vesicles of three Saharan rodents (MLVSP21 from Meriones libycus, MSVSP21 from Meriones shawi, and MCVSP21 from Meriones crassus). The 21-kDa protein was isolated and purified from soluble seminal vesicle proteins of homogenate by one-dimensional polyacrylamide gel electrophoresis (SDS-PAGE). Using polyclonal antibodies directed against POSVP21 (Psammomys obesus seminal vesicles protein of 21 kDa), a major androgen-dependent secretory protein from sand rat seminal vesicles, identified previously as transgelin, we showed an immunological homology with POSVP21 by immunoblotting. These three major androgen-dependent proteins with a same apparent molecular weight of 21 kDa designated as MLVSP21 (Meriones libycus seminal vesicles protein of 21 kDa), MSVSP21 (Meriones shawi seminal vesicles protein of 21 kDa), and MCVSP21 (Meriones crassus seminal vesicles protein of 21 kDa) were localized by immunohistochemistry and identified by applying a proteomic approach. Our results indicated that the isolated proteins MLSVP21, MSSVP21, and MCSVP21 seem to correspond to the same protein: the transgelin. So that transgelin can be used as a specific marker of these rodent physiological reproduction mechanisms. 相似文献
143.
144.
Mebarek Bahnous Abdelmalek Bouraiou Meryem Chelghoum Sofiane Bouacida Thierry Roisnel Farida Smati Chafia Bentchouala Philippe C. Gros Ali Belfaitah 《Bioorganic & medicinal chemistry letters》2013,23(5):1274-1278
Several new highly functionalized imidazolium derivatives were synthesized, via appropriate synthetic routes, using imidazole, 1-methylimidazole and 2-phenyl-1-methylimidazole as key intermediates. The antibacterial activity of the prepared compounds was evaluated against: Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella thipymurium using disk-diffusion and MIC methods. Crystal X-ray structures are reported for six compounds. 相似文献
145.
Subhash Janardhan Bhore Kassim Amelia Edina Wang Sindhuja Priyadharsini Farida Habib Shah 《Bioinformation》2013,9(4):197-206
The identification of genes and understanding of genes'' expression and regulation in common bean (Phaseolus vulgaris L.) is
necessary in order to strategize its improvement using genetic engineering techniques. Generation of expressed sequence tags
(ESTs) is useful in rapid isolation, identification and characterization of the genes. To study the gene expression in P. vulgaris pods
tissue, ESTs generation work was initiated. Early stage and late stage bean-pod-tissues cDNA libraries were constructed using
CloneMiner cDNA library construction kit. In total, 5972 EST clones were isolated using random method of gene isolation. While
processing ESTs, we found lycopene β-cyclase (PvLCY-β) and β-carotene hydroxylase (PvCHY-β) gene''s cDNA. In carotenoid
biosynthesis pathway, PvLCY-β catalyzes the production of carotene; and PvCHY-β is known to function as a catalyst in the
production of lutein and zeaxanthin. To understand more about PvLCY-β and PvCHY-β, both strands of both cDNA clones were
sequenced using M13 forward and reverse primers. Nucleotide and deduced protein sequences were analyzed and annotated
using online bioinformatics tools. Results showed that PvLCY-β and PvCHY-β cDNAs are 1639 and 1107 bp in length, respectively.
Analysis results showed that PvLCY-β and PvCHY-β gene''s cDNA contains an open reading frame (ORF) that encodes for 502 and
305 amino acid residues, respectively. The deduced protein sequence analysis results also showed the presence of conserved
domains needed for PvLCY-β and PvCHY-β functions. The phylogenetic analysis of both PvLCY-β and PvCHY-β proteins showed
it''s closeness with the LCY-β and CHY-β proteins from Glycine max, respectively. The nucleotide sequence of PvLCY-β and PvCHY-β
gene''s cDNA and it''s annotation is reported in this paper. 相似文献
146.
Mizuta K Gallos G Zhu D Mizuta F Goubaeva F Xu D Panettieri RA Yang J Emala CW 《American journal of physiology. Lung cellular and molecular physiology》2008,294(3):L523-L534
Neuropeptide tachykinins (substance P, neurokinin A, and neurokinin B) are present in peripheral terminals of sensory nerve fibers within the respiratory tract and cause airway contractile responses and hyperresponsiveness in humans and most mammalian species. Three subtypes of neurokinin receptors (NK1R, NK2R, and NK3R) classically couple to Gq protein-mediated inositol 1,4,5-trisphosphate (IP3) synthesis and liberation of intracellular Ca2+, which initiates contraction, but their expression and calcium signaling mechanisms are incompletely understood in airway smooth muscle. All three subtypes were identified in native and cultured human airway smooth muscle (HASM) and were subsequently overexpressed in HASM cells using a human immunodeficiency virus-1-based lentivirus transduction system. Specific NKR agonists {NK1R, [Sar9,Met(O2)11]-substance P; NK2R, [beta-Ala8]-neurokinin A(4-10); NK3R, senktide} stimulated inositol phosphate synthesis and increased intracellular Ca2+ concentration ([Ca2+]i) in native HASM cells and in HASM cells transfected with each NKR subtype. These effects were blocked by NKR-selective antagonists (NK1R, L-732138; NK2R, GR-159897; NK3R, SB-222200). The initial transient and sustained phases of increased [Ca2+]i were predominantly inhibited by the IP3 receptor antagonist 2-aminoethoxydiphenyl borate (2-APB) or the store-operated Ca2+ channel antagonist SKF-96365, respectively. These results show that all three subtypes of NKRs are expressed in native HASM cells and that IP3 levels are the primary mediators of NKR-stimulated initial [Ca2+]i increases, whereas store-operated Ca2+ channels mediate the sustained phase of the [Ca2+]i increase. 相似文献
147.
Werner M Rosa E Al Emran O Goldberg AR George ST 《Antisense & nucleic acid drug development》1999,9(1):81-88
The endoribonuclease RNase P processes tRNA-like structures that are assembled out of two separate strands. In these bimolecular constructs, one of the strands is cleaved by the enzyme, and the other one is called the external guide sequence (EGS). A number of EGS with different mutations and deletions were tested for the ability to induce cleavage with human RNase P. Different domains of the original tRNAtyr-like structure were deleted or modified. The anticodon stem and loop and the variable loop could be deleted without a detrimental effect on recognition by RNase P. Modifications in the lengths of T stem and aminoacyl acceptor stem led to a decrease in the relative amount of cleavage, whereas modifications of the D stem were more permissible. Single nucleotide deletions in the T loop reduced cleavage to different extents, depending on the position. Values for the Kd of complex formation of bimolecular constructs with annealing arms of varying lengths ranged from 0.2 nM to 28 nM. A cleavage rate of 1 min(-1) was measured for both the bimolecular target-EGS complex and tRNA precursor. 相似文献
148.
149.
Helmia Farida Juli?tte A. Severin M. Hussein Gasem Monique Keuter Hendro Wahyono Peterhans van den Broek Peter W. M. Hermans Henri A. Verbrugh 《PloS one》2014,9(1)
Introduction
Streptococcus pneumoniae is a worldwide occurring pathogen Nasopharyngeal carriage of Streptococcus pneumoniae precedes pneumonia and other pneumococcal diseases in the community. Little is known about S. pneumoniae carriage in Indonesia, complicating strategies to control pneumococcal diseases. We investigated nasopharyngeal carriage of S. pneumoniae in Semarang, Indonesia.Methods
A population-based survey was performed in Semarang, Indonesia. Nasopharyngeal swabs and questionnaires were taken from 496 healthy young (6–60 month-old) children and 45–70 year-old adults.Results
Forty-three percent of children aged 6–60 months and 11% of adults aged 45–75 years carried S. pneumoniae. Determinants of carriage were being a child (OR 7.7; 95% CI = 4.5–13.0), passive smoking (OR 2.1; 95% CI = 1.3–3.4), and contact with toddler(s) at home (OR 3.0; 95% CI = 1.9–4.7). The most frequent serotypes found were 6A/B and 15B/C. The current commercially available vaccines cover <50% serotypes found in children. Twenty-four percent of S. pneumoniae strains were penicillin non-susceptible, and 45% were resistant to cotrimoxazol.Conclusions
The limited coverage of commercially available vaccines against the serotypes found in this population, and the high proportion of non-susceptibility to penicillin and cotrimoxazol suggest the need for region-specific information and strategies to control S. pneumoniae. 相似文献150.
INF2 is a unique formin that can both polymerize and depolymerize actin filaments. Mutations in INF2 cause the kidney disease focal and segmental glomerulosclerosis. INF2 can be expressed as two C-terminal splice variants: CAAX and non-CAAX. The CAAX isoform contains a C-terminal prenyl group and is tightly bound to endoplasmic reticulum (ER). The localization pattern and cellular function of the non-CAAX isoform have not been studied. Here we find that the two isoforms are expressed in a cell type-dependent manner, with CAAX predominant in 3T3 fibroblasts and non-CAAX predominant in U2OS, HeLa, and Jurkat cells. Although INF2-CAAX is ER localized in an actin-independent manner, INF2-non-CAAX localizes in an actin-dependent meshwork pattern distinct from ER. INF2-non-CAAX is loosely attached to this meshwork, being extracted by brief digitonin treatment. Suppression of INF2-non-CAAX causes fragmentation of the Golgi apparatus. This effect is counteracted by treatment with the actin monomer-sequestering drug latrunculin B. We also find discrete patches of actin filaments in the peri-Golgi region, and these patches are reduced upon INF2 suppression. Our results suggest that the non-CAAX isoform of INF2 serves a distinct cellular function from that of the CAAX isoform. 相似文献