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101.
The localization of two salmon-type gonadotropin-releasing hormone (sGnRH) precursors, pro-sGnRH-I (short type) and pro-sGnRH-II (long type), was investigated by using in situ hybridization techniques in the brain of the landlocked sockeye salmon, Oncorhynchus nerka. We used 30-mer oligonucleotide probes complementary to pro-sGnRH-I and pro-sGnRH-II cDNA. No significant differences were observed in the localization of sGnRH neurons expressing pro-sGnRH-I and pro-sGnRH-II mRNAs; both were expressed in the olfactory nerve, the olfactory bulbs, the regions between the olfactory bulb and telencephalon, the ventral telencephalon, the preoptic area, and the hypothalamus. Almost all sGnRH neurons examined co-expressed both precursors. The expression of two sGnRH precursors in the same neuron and the wide distribution of such neurons in the brain suggest that there are no functional differences between the two precursors.  相似文献   
102.
103.
Junín virus (JUNV), an arenavirus, is the causative agent of Argentine hemorrhagic fever, an infectious human disease with 15-30% case fatality. The pathogenesis of AHF is still not well understood. Elevated levels of interferon and cytokines are reported in AHF patients, which might be correlated to the severity of the disease. However the innate immune response to JUNV infection has not been well evaluated. Previous studies have suggested that the virulent strain of JUNV does not induce IFN in human macrophages and monocytes, whereas the attenuated strain of JUNV was found to induce IFN response in murine macrophages via the TLR-2 signaling pathway. In this study, we investigated the interaction between JUNV and IFN pathway in human epithelial cells highly permissive to JUNV infection. We have determined the expression pattern of interferon-stimulated genes (ISGs) and IFN-β at both mRNA and protein levels during JUNV infection. Our results clearly indicate that JUNV infection activates the type I IFN response. STAT1 phosphorylation, a downstream marker of activation of IFN signaling pathway, was readily detected in JUNV infected IFN-competent cells. Our studies also demonstrated for the first time that RIG-I was required for IFN production during JUNV infection. IFN activation was detected during infection by either the virulent or attenuated vaccine strain of JUNV. Curiously, both virus strains were relatively insensitive to human IFN treatment. Our studies collectively indicated that JUNV infection could induce host type I IFN response and provided new insights into the interaction between JUNV and host innate immune system, which might be important in future studies on vaccine development and antiviral treatment.  相似文献   
104.
Previous studies in the Mexican population have failed to show an effect of apolipoprotein E (APOE) polymorphism on the lipid profile. The purpose of the present study was to determine the frequencies of APOE phenotypes, and their influence on lipid and apolipoprotein levels in a random sample of Mexican adolescents living in Mexico City. APOE polymorphism, fasting insulin levels, lipid levels, and apolipoprotein levels were determined in 420 adolescents. We found a high frequency of APOE*3 subjects (89.5%) and a low frequency of APOE*2 (3.0%) and APOE*4 (7.5%) subjects. The APOE*4 subjects (including APOE 4,3 and APOE 4,4) showed the highest concentrations of total cholesterol, low-density lipoprotein cholesterol, and apoB and the lowest high-density lipoprotein cholesterol levels, whereas carriers of the APOE*2 allele (APOE 3,2 and APOE 2,2) had the lowest values for total and low-density lipoprotein cholesterol and the highest concentrations of high-density lipoprotein cholesterol. No significant differences in triglyceride and insulin levels among subjects with different APOE polymorphisms were observed. Unlike previous studies in the Mexican population, our results show that lipid and lipoprotein levels are under the influence of APOE polymorphism. As in whites, APOE*4 may be a cardiovascular risk factor in the Mexican population.  相似文献   
105.
miRNAs have been shown to be essential for normal cartilage development in the mouse. However, the role of specific miRNAs in cartilage function is unknown. Using rarely available healthy human chondrocytes (obtained from 8 to 50 year old patients), we detected a most highly abundant primary miRNA H19, whose expression was heavily dependent on cartilage master regulator SOX9. Across a range of murine tissues, expression of both H19- and H19-derived miR-675 mirrored that of cartilage-specific SOX9. miR-675 was shown to up-regulate the essential cartilage matrix component COL2A1, and overexpression of miR-675 rescued COL2A1 levels in H19- or SOX9-depleted cells. We thus provide evidence that SOX9 positively regulates COL2A1 in human articular chondrocytes via a previously unreported miR-675-dependent mechanism. This represents a novel pathway regulating cartilage matrix production and identifies miR-675 as a promising new target for cartilage repair.  相似文献   
106.
Genetic control of shoot organ boundaries   总被引:6,自引:0,他引:6  
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107.
108.

Background

Previous studies indicate that in published reports, trial results can be distorted by the use of “spin” (specific reporting strategies, intentional or unintentional, emphasizing the beneficial effect of the experimental treatment). We aimed to (1) evaluate the presence of “spin” in press releases and associated media coverage; and (2) evaluate whether findings of randomized controlled trials (RCTs) based on press releases and media coverage are misinterpreted.

Methods and Findings

We systematically searched for all press releases indexed in the EurekAlert! database between December 2009 and March 2010. Of the 498 press releases retrieved and screened, we included press releases for all two-arm, parallel-group RCTs (n = 70). We obtained a copy of the scientific article to which the press release related and we systematically searched for related news items using Lexis Nexis.“Spin,” defined as specific reporting strategies (intentional or unintentional) emphasizing the beneficial effect of the experimental treatment, was identified in 28 (40%) scientific article abstract conclusions and in 33 (47%) press releases. From bivariate and multivariable analysis assessing the journal type, funding source, sample size, type of treatment (drug or other), results of the primary outcomes (all nonstatistically significant versus other), author of the press release, and the presence of “spin” in the abstract conclusion, the only factor associated, with “spin” in the press release was “spin” in the article abstract conclusions (relative risk [RR] 5.6, [95% CI 2.8–11.1], p<0.001). Findings of RCTs based on press releases were overestimated for 19 (27%) reports. News items were identified for 41 RCTs; 21 (51%) were reported with “spin,” mainly the same type of “spin” as those identified in the press release and article abstract conclusion. Findings of RCTs based on the news item was overestimated for ten (24%) reports.

Conclusion

“Spin” was identified in about half of press releases and media coverage. In multivariable analysis, the main factor associated with “spin” in press releases was the presence of “spin” in the article abstract conclusion.  相似文献   
109.
The primitive religious view of tribes in Azerbaijan Bronze Age was in close connection with nature. Fire rituals had taken the main place in ancient people’s belief.  相似文献   
110.
Limited proteolysis of beta-1,3-glucanase A1 by three different proteases, trypsin, chymotrypsin, and papain, gave three major active fragments. The sizes of the three major fragments generated by each protease treatment were identical to those of beta-1,3-glucanase A2, A3, and A4 detected in both the culture supernatant of Bacillus circulans WL-12 and the periplasmic space of Escherichia coli carrying a cloned glcA gene. These results indicate a four-domain structure for the enzyme. At the N terminus of the glucanase, duplicated segments of approximately 100 amino acids were observed. N-terminal amino acid sequence analysis revealed that the active fragments with sizes corresponding to those of A2 and A3 lack the first segment (domain) and both duplicated segments (domains), respectively. The fragment corresponding to A4 lacks both duplicated segments and the following ca. 120-amino-acid region. By losing the first, second, and third (corresponding to the segment of 120 amino acids) domains, beta-1,3-glucanase progressively lost the ability to bind to pachyman, beta-1,3-glucan. An active fragment which did not have the three N-terminal domains did not show significant binding to pachyman. Thus, all three N-terminal domains contribute to binding to beta-1,3-glucan, and the presence of three domains confers the highest binding activity on the glucanase. The loss of these binding domains remarkably decreased pachyman-hydrolyzing activity, indicating that the binding activity is essential for the efficient hydrolysis of insoluble beta-1,3-glucan.  相似文献   
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