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161.
So MT Leon TY Cheng G Tang CS Miao XP Cornes BK Diem NN Cui L Ngan ES Lui VC Wu XZ Wang B Wang H Yuan ZW Huang LM Li L Xia H Zhu D Liu J Nguyen TL Chan IH Chung PH Liu XL Zhang R Wong KK Sham PC Cherny SS Tam PK Garcia-Barcelo MM 《PloS one》2011,6(12):e28986
Rare (RVs) and common variants of the RET gene contribute to Hirschsprung disease (HSCR; congenital aganglionosis). While RET common variants are strongly associated with the commonest manifestation of the disease (males; short-segment aganglionosis; sporadic), rare coding sequence (CDS) variants are more frequently found in the lesser common and more severe forms of the disease (females; long/total colonic aganglionosis; familial).Here we present the screening for RVs in the RET CDS and intron/exon boundaries of 601 Chinese HSCR patients, the largest number of patients ever reported. We identified 61 different heterozygous RVs (50 novel) distributed among 100 patients (16.64%). Those include 14 silent, 29 missense, 5 nonsense, 4 frame-shifts, and one in-frame amino-acid deletion in the CDS, two splice-site deletions, 4 nucleotide substitutions and a 22-bp deletion in the intron/exon boundaries and 1 single-nucleotide substitution in the 5' untranslated region. Exonic variants were mainly clustered in RET the extracellular domain. RET RVs were more frequent among patients with the most severe phenotype (24% vs. 15% in short-HSCR). Phasing RVs with the RET HSCR-associated haplotype suggests that RVs do not underlie the undisputable association of RET common variants with HSCR. None of the variants were found in 250 Chinese controls. 相似文献
162.
Kawaguchi S Kurihara H King R Hale L Berli T Robinson JP Ishida A Wakita M Virtue P Nicol S Ishimatsu A 《Biology letters》2011,7(2):288-291
Antarctic krill embryos and larvae were experimentally exposed to 380 (control), 1000 and 2000 µatm pCO2 in order to assess the possible impact of ocean acidification on early development of krill. No significant effects were detected on embryonic development or larval behaviour at 1000 µatm pCO2; however, at 2000 µatm pCO2 development was disrupted before gastrulation in 90 per cent of embryos, and no larvae hatched successfully. Our model projections demonstrated that Southern Ocean sea water pCO2 could rise up to 1400 µatm in krill''s depth range under the IPCC IS92a scenario by the year 2100 (atmospheric pCO2 788 µatm). These results point out the urgent need for understanding the pCO2-response relationship for krill developmental and later stages, in order to predict the possible fate of this key species in the Southern Ocean. 相似文献
163.
Baatz F Nijhuis M Lemaire M Riedijk M Wensing AM Servais JY van Ham PM Hoepelman AI Koopmans PP Sprenger HG Devaux C Schmit JC Perez Bercoff D 《PloS one》2011,6(7):e21535
Resistance mutations to the HIV-1 fusion inhibitor enfuvirtide emerge mainly within the drug's target region, HR1, and compensatory mutations have been described within HR2. The surrounding envelope (env) genetic context might also contribute to resistance, although to what extent and through which determinants remains elusive. To quantify the direct role of the env context in resistance to enfuvirtide and in viral infectivity, we compared enfuvirtide susceptibility and infectivity of recombinant viral pairs harboring the HR1-HR2 region or the full Env ectodomain of longitudinal env clones from 5 heavily treated patients failing enfuvirtide therapy. Prior to enfuvirtide treatment onset, no env carried known resistance mutations and full Env viruses were on average less susceptible than HR1-HR2 recombinants. All escape clones carried at least one of G36D, V38A, N42D and/or N43D/S in HR1, and accordingly, resistance increased 11- to 2800-fold relative to baseline. Resistance of full Env recombinant viruses was similar to resistance of their HR1-HR2 counterpart, indicating that HR1 and HR2 are the main contributors to resistance. Strictly X4 viruses were more resistant than strictly R5 viruses, while dual-tropic Envs featured similar resistance levels irrespective of the coreceptor expressed by the cell line used. Full Env recombinants from all patients gained infectivity under prolonged drug pressure; for HR1-HR2 viruses, infectivity remained steady for 3/5 patients, while for 2/5 patients, gains in infectivity paralleled those of the corresponding full Env recombinants, indicating that the env genetic context accounts mainly for infectivity adjustments. Phylogenetic analyses revealed that quasispecies selection is a step-wise process where selection of enfuvirtide resistance is a dominant factor early during therapy, while increased infectivity is the prominent driver under prolonged therapy. 相似文献
164.
Lin AY Chua MS Choi YL Yeh W Kim YH Azzi R Adams GA Sainani K van de Rijn M So SK Pollack JR 《PloS one》2011,6(2):e16636
Purpose
We sought to identify genes of clinical significance to predict survival and the risk for colorectal liver metastasis (CLM), the most common site of metastasis from colorectal cancer (CRC).Patients and Methods
We profiled gene expression in 31 specimens from primary CRC and 32 unmatched specimens of CLM, and performed Significance Analysis of Microarrays (SAM) to identify genes differentially expressed between these two groups. To characterize the clinical relevance of two highly-ranked differentially-expressed genes, we analyzed the expression of secreted phosphoprotein 1 (SPP1 or osteopontin) and lymphoid enhancer factor-1 (LEF1) by immunohistochemistry using a tissue microarray (TMA) representing an independent set of 154 patients with primary CRC.Results
Supervised analysis using SAM identified 963 genes with significantly higher expression in CLM compared to primary CRC, with a false discovery rate of <0.5%. TMA analysis showed SPP1 and LEF1 protein overexpression in 60% and 44% of CRC cases, respectively. Subsequent occurrence of CLM was significantly correlated with the overexpression of LEF1 (chi-square p = 0.042), but not SPP1 (p = 0.14). Kaplan Meier analysis revealed significantly worse survival in patients with overexpression of LEF1 (p<0.01), but not SPP1 (p = 0.11). Both univariate and multivariate analyses identified stage (p<0.0001) and LEF1 overexpression (p<0.05) as important prognostic markers, but not tumor grade or SPP1.Conclusion
Among genes differentially expressed between CLM and primary CRC, we demonstrate overexpression of LEF1 in primary CRC to be a prognostic factor for poor survival and increased risk for liver metastasis. 相似文献165.
166.
Ludmila Sošková 《Folia microbiologica》1960,5(6):406-413
Путем пассажей лизогенного штамма Escherichia coli K 12 на средах, содержавших повышающиеся кондентрадии дианистого калия, удалось вырастить варианты, резистентные к 0,4 мол. Кондент KCN. Полученные резистентые штаммы сохраняют свою резистентность и при пассажах на средах без дианистого калия. С приобретением устойчивости к дианистому калиию у этих штаммов изменились и другие свойства в сравнении с исходным штаммом. Некоторые изменения оказались обратимыми, другие, — как биохимические изменения, изменения чувствительности к ?агам и в продукции ?ага, — сохранялись стабильно и после 50 пассажей на средах без цианистого калия. С помощью ?ага, выделенного из штамма К 12, устойчивого к 0,4 мол. концентрации цианистого калия, удалась трансдукция не только устойчивости к цианистому калию, но одновременно и чувствительности к ?агам группы coli Т и утраты способности сбраживать дульцит. Однако связь между этими особенностями не была стопроцентной, так как перенесенная устойчивость к дианистому калию оказалась несколько более низкой, чем исходная (0,3 мол. Вместо 0,4 мол.), а бактерии после трансдукдии продуцировали не только ?аг α, как бактериидоноры, но и преимущественно первоначальный ?аг. 相似文献
167.
168.
169.
Spn1 regulates the GNBP3-dependent Toll signaling pathway in Drosophila melanogaster 总被引:1,自引:0,他引:1
Fullaondo A García-Sánchez S Sanz-Parra A Recio E Lee SY Gubb D 《Molecular and cellular biology》2011,31(14):2960-2972
170.
Polynucleotide sequence relationships among Ent plasmids and the relationship between Ent and other plasmids. 总被引:18,自引:13,他引:18 下载免费PDF全文
Deoxyribonucleic acid-deoxyribonucleic acid hybridization studies reveal that the plasmids coding for the production of heat stable and heat labile enteroxtoxins of Escherichia coli, regardless of their origin, have a majority of their polynucleotide sequences in common, but are not related in any significant way to those plasmids coding for the synthesis of only ST toxin. The heat stable and heat labile plasmids also share a significant degree of their polynucleotide sequences with plasmids of the FI and FII incompatibility groups, but not with R factors belonging to the I, N, W, P, or X incompatibility groups. 相似文献