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71.
Chen-Tzu Kuo Bing-Chang Chen Chung-Chi Yu Chih-Ming Weng Ming-Jen Hsu Chien-Chih Chen Mei-Chieh Chen Che-Ming Teng Shiow-Lin Pan Mauo-Ying Bien Chung-Hung Shih Chien-Huang Lin 《Journal of biomedical science》2009,16(1):1-15
In the present study, we explore the role of apoptosis signal-regulating kinase 1 (ASK1) in denbinobin-induced apoptosis in human lung adenocarcinoma (A549) cells. Denbinobin-induced cell apoptosis was attenuated by an ASK1 dominant-negative mutant (ASK1DN), two antioxidants (N-acetyl-L-cysteine (NAC) and glutathione (GSH)), a c-Jun N-terminal kinase (JNK) inhibitor (SP600125), and an activator protein-1 (AP-1) inhibitor (curcumin). Treatment of A549 cells with denbinobin caused increases in ASK1 activity and reactive oxygen species (ROS) production, and these effects were inhibited by NAC and GSH. Stimulation of A549 cells with denbinobin caused JNK activation; this effect was markedly inhibited by NAC, GSH, and ASK1DN. Denbinobin induced c-Jun phosphorylation, the formation of an AP-1-specific DNA-protein complex, and Bim expression. Bim knockdown using a bim short interfering RNA strategy also reduced denbinobin-induced A549 cell apoptosis. The denbinobin-mediated increases in c-Jun phosphorylation and Bim expression were inhibited by NAC, GSH, SP600125, ASK1DN, JNK1DN, and JNK2DN. These results suggest that denbinobin might activate ASK1 through ROS production to cause JNK/AP-1 activation, which in turn induces Bim expression, and ultimately results in A549 cell apoptosis. 相似文献
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The Sacramento splittail is an endemic cyprinid fish of the San Francisco estuary and its tributaries, which is a highly manipulated,
constantly changing ecosystem. Splittail is the only extant member of its genus and is listed as a federal and California
Species of Special Concern due to uncertainties regarding long-term abundance trends. Determining population structure for
splittail is important because unique populations may contain different adaptive genetic variation, which can allow one population
to persist through future environmental or demographic stochasticity while others become extirpated. To assess splittail population
structure, 13 microsatellite markers were used to genotype 489 young-of-year splittail from five major rivers draining into
the estuary: Cosumnes, Napa, Petaluma, Sacramento, and San Joaquin Rivers. Two genetically distinct populations were found
to exist within our study region; one largely comprised of splittail collected from the Petaluma and Napa Rivers and the second
comprised of splittail collected from tributaries in Californiaȁ9s Central Valley: Cosumnes, Sacramento, and San Joaquin Rivers.
These results were replicated in two consecutive years with both distance and model-based algorithms. The genetic distinction
between these two populations appears correlated with salinity differences between migratory regions and spawning grounds.
Splittail from the Petaluma River exhibited a significantly higher degree of differentiation from the Central Valley population
than did Napa River splittail. Our results suggest on-going monitoring programs are probably highly biased towards sampling
splittail from the Central Valley population. Understanding population dynamics of splittail could be improved if monitoring
programs were expanded to include all splittail populations. 相似文献
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Kirsten Labudda Stefan Kreisel Thomas Beblo Markus Mertens Oleg Kurlandchikov Christian G. Bien Martin Driessen Friedrich G. Woermann 《PloS one》2013,8(12)
Results of MRI volumetry in Borderline Personality Disorder (BPD) are inconsistent. Some, but not all, studies reported decreased hippocampus, amygdala, and/or prefrontal volumes. In the current study, we used rater-independent voxel-based morphometry (VBM) in 33 female BPD patients and 33 healthy women. We measured gray matter (GM) volumes of the whole brain and of three volumes of interest (VOI), i.e., the hippocampus/parahippocampal gyrus, the amygdala and the anterior cingulate gyrus (ACC). Analyses were conducted using lifetime diagnoses of posttraumatic stress disorder (PTSD) and major depression (MD) as covariates. We used adversive childhood experiences and the numbers of BPD criteria (as an indicator of disorder severity) to investigate associations with GM volumes. We did not find volume differences between BPD patients and healthy subject, neither of the whole brain nor of the three VOIs, independent of presence or absence of comorbid PTSD and MD. We also did not find a relationship between childhood maltreatment and the patients’ brain volumes. However, within the patient group, the number of BPD criteria fulfilled was inversely correlated with left hippocampal/parahippocampal volume (x=-32, y=-23, z=-18, k=496, t=5.08, p=.007). Consequently, mesiotemporal GM volumes do not seem to differentiate patients from healthy subjects, but might be associated with symptom severity within the BPD group. 相似文献
74.
Hughes AL Lee CY Bien CM Espenshade PJ 《The Journal of biological chemistry》2007,282(33):24388-24396
In fission yeast, orthologs of mammalian SREBP and Scap, called Sre1 and Scp1, monitor oxygen-dependent sterol synthesis as a measure of cellular oxygen supply. Under low oxygen conditions, sterol synthesis is inhibited, and Sre1 cleavage is activated. However, the sterol signal for Sre1 activation is unknown. In this study, we characterized the sterol signal for Sre1 activation using a combination of Sre1 cleavage assays and gas chromatography sterol analysis. We find that Sre1 activation is regulated by levels of the 4-methyl sterols 24-methylene lanosterol and 4,4-dimethylfecosterol under conditions of low oxygen and cell stress. Both increases and decreases in the level of these ergosterol pathway intermediates induce Sre1 proteolysis in a Scp1-dependent manner. The SREBP ortholog in the pathogenic fungus Cryptococcus neoformans is also activated by high levels of 4-methyl sterols, suggesting that this signal for SREBP activation is conserved among unicellular eukaryotes. Finally, we provide evidence that the sterol-sensing domain of Scp1 is important for regulating Sre1 proteolysis. The conserved mutations Y247C, L264F, and D392N in Scp1 that render Scap insensitive to sterols cause constitutive Sre1 activation. These findings indicate that unlike Scap, fission yeast Scp1 responds to 4-methyl sterols and thus shares properties with mammalian HMG-CoA reductase, a sterol-sensing domain protein whose degradation is regulated by the 4-methyl sterol lanosterol. 相似文献
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Characterization of emerging European-like porcine reproductive and respiratory syndrome virus isolates in the United States 总被引:1,自引:0,他引:1 下载免费PDF全文
Ropp SL Wees CE Fang Y Nelson EA Rossow KD Bien M Arndt B Preszler S Steen P Christopher-Hennings J Collins JE Benfield DA Faaberg KS 《Journal of virology》2004,78(7):3684-3703
European-like field isolates of porcine reproductive and respiratory syndrome virus (PRRSV) have recently emerged in North America. The full-length genomic sequence of an index isolate characterized in 1999, strain EuroPRRSV, served as the reference strain for further studies of the evolution and epidemiology of European-like isolates (type 1) in the United States. Strain EuroPRRSV shared 90.1 to 100% amino acid identity with the prototype European strain, Lelystad, within the structural and nonstructural open reading frames (ORFs) and 95.3% overall nucleotide identity. The 5' untranslated region and two nonstructural regions within ORF 1 were closely examined due to significant divergence from strain Lelystad. A 51-bp deletion in a region within ORF 1a, coding for nonstructural protein 2 (NSP2), was observed. Sequence analysis of the structural ORFs 2 to 7 of additional European-like isolates indicated that these isolates share 93% nucleotide identity with one another and 95 to 96% identity with the Lelystad strain but only 70% identity with the North American reference strain VR-2332. Phylogenetic analysis with published PRRSV ORF 3, 5, and 7 nucleotide sequences indicated that these newly emerging isolates form a clade with the Lelystad and United Kingdom PRRSV isolates. Detailed analysis of four of these isolates with a panel of 60 monoclonal antibodies directed against the structural proteins confirmed a recognition pattern that was more consistent with strain Lelystad than with other North American isolates. 相似文献
78.
Background
Thirty-four countries worldwide have abnormally high sex ratios (>102 men per 100 women), resulting in over 100 million missing women. Widespread sex selective abortion, neglect of young girls leading to premature mortality, and gendered migration have contributed to these persistent and increasing distortions. Abnormally high adult sex ratios in communities may drive sexually transmitted disease (STD) spread where women are missing and men cannot find stable partners. We systematically reviewed evidence on the association between high community sex ratios and individual sexual behaviors.Methods and Findings
Seven databases (PubMed, Web of Science, Embase, Scopus, The Cochrane Database of Systematic Reviews, Sociological Abstracts, and PopLINE) were searched without restrictions on time or location. We followed PRISMA guidelines and evaluated quality according to STROBE criteria. 1093 citations were identified and six studies describing 57,054 individuals were included for review. All six studies showed an association between high community sex ratios and individual sexual risk behaviors. In high sex ratio communities, women were more likely to have multiple sex partners and men were more likely to delay first sexual intercourse and purchase sex. Only two studies included STD outcomes.Conclusions
High community sex ratios were associated with increased individual sexual risk behavior among both men and women. However, none of the studies examined unprotected sex or appropriately adjusted for gendered migration. Further studies are needed to understand the effect of community sex ratios on sexual health and to inform comprehensive STD control interventions. 相似文献79.
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