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51.
We developed Ulysses as a user-oriented system that uses a process called Interolog Analysis for the parallel analysis and display of protein interactions detected in various species. Ulysses was designed to perform such Interolog Analysis by the projection of model organism interaction data onto homologous human proteins, and thus serves as an accelerator for the analysis of uncharacterized human proteins. The relevance of projections was assessed and validated against published reference collections. All source code is freely available, and the Ulysses system can be accessed via a web interface .  相似文献   
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The molecular mechanism of human immunodeficiency virus type 1 (HIV-1) entry into cells involves specific interactions between the viral envelope glycoprotein gp120 and two target cell proteins, CD4 and either CCR5 or CXCR4 chemokine receptors. In order to delineate the functional role of HIV-1 gp120 subdomains of dualtropic strains in CCR5 coreceptor usage, we used a panel of chimeric viruses in which the V1/V2 and V3 domains of gp120 from the dualtropic HIV-1(KMT) isolate were introduced either alone or in combination into the T-tropic HIV-1(NL4-3) background. These chimeric constructs were employed in cell-cell fusion and cell-free virus infectivity assays using cell lines expressing CD4 and the CCR5 chemokine receptor. In both assays, the V3 domain of HIV-1(KMT) but not the V1/V2 domain proved to be the principal determinant of CCR5 coreceptor usage. However, in the cell-free viral infectivity assay although a chimeric virus with a combined V1/V2 and V3 domains of HIV-1(KMT) efficiently fused with coreceptor expressing cells, yet its infectivity was markedly diminished in CCR5 as well as CXCR4 expressing cells. Restoring a comparable level of infection of such chimeric virus required the C3-V5 domain from HIV-1(KMT) to be introduced. Our present findings confirmed that the V3 domain is the major determinant of fusion activity and cellular tropism, and demonstrated a dispensable role for the V1/V2 domain. In addition the C3-V5 domain appeared to play an important role in viral infectivity when the corresponding V1/V2 and V3 domains are present.  相似文献   
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IntroductionMicrochimeric male fetal cells (MFCs) have been associated with systemic lupus erythematosus, and published studies have further correlated MFC with lupus nephritis (LN). In the present study, we evaluated the frequency of MFC in the renal tissue of patients with LN.MethodsTwenty-seven renal biopsies were evaluated: Fourteen were from women with clinical and laboratory findings of LN, and thirteen were from controls. Genomic DNA was extracted from kidney biopsies, and the male fetal DNA was quantified using real-time quantitative polymerase chain reactions for the detection of specific Y chromosome sequences.ResultsMFCs were detected in 9 (64%) of 14 of patients with LN, whereas no MFCs were found in the control group (P = 0.0006). No differences in pregnancy history were found between patients with LN and the control group. Significantly higher amounts of MFCs were found in patients with LN with serum creatinine ≤1.5 mg/dl. Furthermore, women with MFCs had significantly better renal function at the time of biopsy (P = 0.03). In contrast, patients with LN without MFCs presented with more severe forms of glomerulonephritis (World Health Organization class IV = 60% and class V = 40%).ConclusionsOur data indicate a high prevalence of MFCs in renal biopsy specimens from women with LN, suggesting a role for MFCs in the etiology of LN. The present report also provides some evidence that MFCs could have a beneficial effect in this disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0615-4) contains supplementary material, which is available to authorized users.  相似文献   
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Microglia are tissue macrophages of the central nervous system (CNS) that control tissue homeostasis. Microglia dysregulation is thought to be causal for a group of neuropsychiatric, neurodegenerative and neuroinflammatory diseases, called “microgliopathies”. However, how the intracellular stimulation machinery in microglia is controlled is poorly understood. Here, we identified the ubiquitin‐specific protease (Usp) 18 in white matter microglia that essentially contributes to microglial quiescence. We further found that microglial Usp18 negatively regulates the activation of Stat1 and concomitant induction of interferon‐induced genes, thereby terminating IFN signaling. The Usp18‐mediated control was independent from its catalytic activity but instead required the interaction with Ifnar2. Additionally, the absence of Ifnar1 restored microglial activation, indicating a tonic IFN signal which needs to be negatively controlled by Usp18 under non‐diseased conditions. These results identify Usp18 as a critical negative regulator of microglia activation and demonstrate a protective role of Usp18 for microglia function by regulating the Ifnar pathway. The findings establish Usp18 as a new molecule preventing destructive microgliopathy.  相似文献   
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This study aimed to evaluate the role of APOE polymorphisms (rs429358 and rs7412) in the risk of age-related macular degeneration in a sample of the Southeastern Brazilian population. Seven hundred and five unrelated individuals were analyzed, 334 with age-related macular degeneration (case group), and 371 without the disease (control group). In the case group, patients were further stratified according to disease phenotypes, divided into dry and wet age-related macular degeneration, and non-advanced and advanced age-related macular degeneration. APOE polymorphisms (rs429358 and rs7412) were evaluated through polymerase chain reaction and direct sequencing. In the comparison of cases vs. controls, none of the associations reached statistical significance, considering the Bonferroni-adjusted P-value, although there was a suggestive protection for the E3/E4 genotype (OR = 0.626; P-value = 0.037) and E4 carriers (OR = 0.6515; P-value = 0.047). Statistically significant protection for both the E3/E4 genotype and E4 carriers was observed in the comparisons: advanced age-related macular degeneration vs. controls (OR = 0.3665, P-value = 0.491 × 10−3 and OR = 0.4031, P-value = 0.814 × 10−3, respectively), advanced age-related macular degeneration vs. non-advanced age-related macular degeneration (OR = 0.2529, P-value = 0.659 × 10−4 and OR = 0.2692, P-value = 0.631 × 10−4, respectively). In the comparison of wet age-related macular degeneration vs. control, protection was statistically significant only for E3/E4 (OR = 0.4052, P-value = 0.001). None of the comparisons demonstrated any significant association for E2 genotypes or E2 carriers in age-related macular degeneration risk in this study. Findings suggest a protective role of the E4 haplotype in the APOE gene in the risk for advanced and wet forms of age-related macular degeneration, in a sample of the Brazilian population. To our knowledge, this is the first Brazilian study to show the association between APOE polymorphisms and age-related macular degeneration.  相似文献   
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Considering the high rate of osteoclast-related diseases worldwide, research targeting osteoclast formation/function is crucial. In vitro, we demonstrated that chitooligosaccharide (CS) dramatically inhibited osteoclastogenesis as well as osteoclast function dose-dependently. CS suppressed osteoclast-specific genes expression during osteoclastogenesis. Furthermore, we found that CS attenuated receptor activator of nuclear factor kappa B ligand (RANKL)-mediated mitogen-activated protein kinase (MAPK) pathway involving p38, erk1/2, and jnk, leading to the reduced expression of c-fos and nuclear factor of activated T cells c1 (NFATc1) during osteoclast differentiation. In vivo, we found CS protected rats from periodontitis-induced alveolar bone loss by micro-computerized tomography and histological analysis. Overall, CS inhibited RANKL-induced osteoclastogenesis and ligature-induced rat periodontitis model, probably by suppressing the MAPK/c-fos/NFATc1 signaling pathway. Therefore, CS may be a safe and promising treatment for osteoclast-related diseases.  相似文献   
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A highly active mosquitocidal mutant of Lysinibacillus sphaericus Ahmed 2362, namely, UCR-146, was efficiently produced on cottonseed meal (CSM) medium, using sand as a carrier under solid state fermentation (SSF). The optimum CSM concentration for the highest sporulation and toxin formation was 12%. The maximum toxicity of the tested organism against second instar larvae of Culex pipiens was obtained at 25% moisture content, initial pH 6–7, 1% sodium acetate, 18.9×106 CFU/g inoculum and 6 days incubation period at 30°C. Pilot scale production of UCR-146 under the optimum SSF conditions was assessed in aluminium trays. Spore count, mortality of larvae and LC50 of the final product were 5.5×1010 CFU/g, 72% at 1 part per million (PPM) and 0.54 PPM, respectively. These results were comparable with those obtained from bench-scale production (in flasks). The cost of 1 kg of this bio-larvicide was estimated at US $0.34.  相似文献   
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