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91.
SAR studies were conducted around lead compound 1 using high-throughput parallel solution and solid phase synthesis. Our lead optimization efforts led to the identification of several CCR2b antagonists with potent activity in both binding and functional assays [Compound 71 CCR2b Binding IC(50) 3.2 nM; MCP-1-Induced Chemotaxis IC(50) 0.83 nM; Ca(2+) Flux IC(50) 7.5 nM].  相似文献   
92.
Two new species of the genus Corollospora, namely, C. anglusa sp. nov. with its anamorph Varicosporina anglusa sp. nov. and C. portsaidica sp. nov., which were isolated from the coast of the Mediterranean Sea in Egypt, are described in this article based on morphological and molecular evidence. The two new species have one-septate ascospores. Corollospora anglusa resembles C. gracilis by having narrow one-septate hyaline ascospores; however, they differ in ascomata and ascospore dimensions and in pure culture characteristics. Single-ascospore culture of C. anglusa produces the conidia of its anamorph, whereas an anamorph has not been reported for C. gracilis. Varicosporina anglusa differs from the other two known Varicosporina species by having conidial branches that are filamentous, rectangularly branched, hypha like, and disarticulated into two- or one-celled fragments. Corollospora portsaidica is morphologically similar to C. cinnamomea, but the two species differ in the dimensions, shape, and ornamentation of the ascospores. The new Corollospora species were confirmed to be divergent from other similar Corollospora species based on phylogenetic analyses of partial sequences of the LSU rDNA region.  相似文献   
93.
Elevated hepatic reactive oxygen species play an important role in pathogenesis of liver diseases, such as alcohol-induced liver injury, hepatitis C virus infection, and nonalcoholic steatohepatitis. In the present study, we investigated and compared the hepatic lipid metabolisms of liver-specific Sod2 (superoxide dismutase 2) knock-out (Sod2 KO), Sod1 knock-out (Sod1 KO), and Sod1/liver-specific Sod2 double knock-out mice (double KO). We observed significant increases in lipid peroxidation and triglyceride (TG) in the liver of Sod1 KO and double KO mice but not in the liver of Sod2 KO mice. We also found that high fat diet enhanced fatty changes of the liver in Sod1 KO and double KO mice but not in Sod2 KO mice. These data indicated that CuZn-SOD deficiency caused lipid accumulation in the liver. To investigate the molecular mechanism of hepatic lipid accumulation in CuZn-SOD-deficient mice, we measured TG secretion rate from liver using Triton WR1339. We found significant decrease of TG secretion in CuZn-SOD-deficient mice. Furthermore, we observed marked degradation of apolipoprotein B (apoB) in the liver and plasma of CuZn-SOD-deficient mice, indicating that degradation of apoB impairs secretion of lipoprotein from the liver. Our data suggest that oxidative stress enhances hepatic lipid accumulation by impaired lipoprotein secretion due to the degradation of apoB in liver.  相似文献   
94.
Oxidative stress is closely linked to the pathogenesis of neurodegeneration. Soluble amyloid β (Aβ) oligomers cause cognitive impairment and synaptic dysfunction in Alzheimer disease (AD). However, the relationship between oligomers, oxidative stress, and their localization during disease progression is uncertain. Our previous study demonstrated that mice deficient in cytoplasmic copper/zinc superoxide dismutase (CuZn-SOD, SOD1) have features of drusen formation, a hallmark of age-related macular degeneration (Imamura, Y., Noda, S., Hashizume, K., Shinoda, K., Yamaguchi, M., Uchiyama, S., Shimizu, T., Mizushima, Y., Shirasawa, T., and Tsubota, K. (2006) Proc. Natl. Acad. Sci. U.S.A. 103, 11282-11287). Amyloid assembly has been implicated as a common mechanism of plaque and drusen formation. Here, we show that Sod1 deficiency in an amyloid precursor protein-overexpressing mouse model (AD mouse, Tg2576) accelerated Aβ oligomerization and memory impairment as compared with control AD mouse and that these phenomena were basically mediated by oxidative damage. The increased plaque and neuronal inflammation were accompanied by the generation of N(ε)-carboxymethyl lysine in advanced glycation end products, a rapid marker of oxidative damage, induced by Sod1 gene-dependent reduction. The Sod1 deletion also caused Tau phosphorylation and the lower levels of synaptophysin. Furthermore, the levels of SOD1 were significantly decreased in human AD patients rather than non-AD age-matched individuals, but mitochondrial SOD (Mn-SOD, SOD2) and extracellular SOD (CuZn-SOD, SOD3) were not. These findings suggest that cytoplasmic superoxide radical plays a critical role in the pathogenesis of AD. Activation of Sod1 may be a therapeutic strategy for the inhibition of AD progression.  相似文献   
95.
Rice dwarf virus (RDV), the causal agent of rice dwarf disease, is a member of the genus Phytoreovirus in the family Reoviridae. RDV is a double-shelled virus with a molecular mass of approximately 70 million Dalton. This virus is widely prevalent and is one of the viruses that cause the most economic damage in many Asian countries. The atomic structure of RDV was determined at 3.5 A resolution by X-ray crystallography. The double-shelled structure consists of two different proteins, the core protein P3 and the outer shell protein P8. The atomic structure shows structural and electrostatic complementarities between both homologous (P3-P3 and P8-P8) and heterologous (P3-P8) interactions, as well as overall conformational changes found in P3-P3 dimer caused by the insertion of amino-terminal loop regions of one of the P3 protein into the other. These interactions suggest how the 900 protein components are built into a higher-ordered virus core structure.  相似文献   
96.
97.

Background

Human serum MUC1 peptide fragments bearing aberrant O-glycans are secreted from columnar epithelial cell surfaces and known as clinically important serum biomarkers for the epithelial carcinoma when a specific monoclonal antibody can probe disease-relevant epitopes. Despite the growing importance of MUC1 glycopeptides as biomarkers, the precise epitopes of most anti-MUC1 monoclonal antibodies remains unclear.

Methods

A novel protocol for the fabrication of versatile microarray displaying peptide/glycopeptide library was investigated for the construction of highly sensitive and accurate epitope mapping assay of various anti-MUC1 antibodies.

Results

Selective imine-coupling between aminooxy-functionalized methacrylic copolymer with phosphorylcholine unit and synthetic MUC1 glycopeptides-capped by a ketone linker at N-terminus provided a facile and seamless protocol for the preparation of glycopeptides microarray platform. It was demonstrated that anti-KL-6 monoclonal antibody shows an extremely specific and strong binding affinity toward MUC1 fragments carrying sialyl T antigen (Neu5Acα2,3Galβ1,3GalNAcα1→) at Pro-Asp-Thr-Arg motif when compared with other seven anti-MUC1 monoclonal antibodies such as VU-3D1, VU-12E1, VU-11E2, Ma552, VU-3C6, SM3, and DF3. The present microarray also uncovered the occurrence of IgG autoantibodies in healthy human sera that bind specifically with sialyl T antigen attached at five potential O-glycosylation sites of MUC1 tandem repeats.

Conclusion

We established a straightforward strategy toward the standardized microarray platform allowing highly sensitive and accurate epitope mapping analysis by reducing the background noise due to nonspecific protein adsorption.

General significance

The present approach would greatly accelerate the discovery research of new class autoantibodies as well as the development of therapeutic mAbs reacting specifically with disease-relevant epitopes.  相似文献   
98.
IFN-γ is a signature Th1 cell associated cytokine critical for the inflammatory response in autoimmunity with both pro-inflammatory and potentially protective functions. IL-17A is the hallmark of T helper 17 (Th17) cell subsets, produced by γδT, CD8+ T, NK and NKT cells. We have taken advantage of our colony of IL-2Rα−/− mice that spontaneously develop both autoimmune cholangitis and inflammatory bowel disease. In this model CD8+ T cells mediate biliary ductular damage, whereas CD4+ T cells mediate induction of colon-specific autoimmunity. Importantly, IL-2Rα−/− mice have high levels of interferon γ (IFN-γ), and interleukin-17A (IL-17A). We produced unique double deletions of mice that were either IL-17A−/−IL-2Rα−/− or IFN-γ−/−IL-2Rα−/− to specifically address the precise role of these two cytokines in the natural history of autoimmune cholangitis and colitis. Of note, deletion of IL-17A in IL-2Rα−/− mice led to more severe liver inflammation, but ameliorated colitis. In contrast, there were no significant changes in the immunopathology of double knock-out IFN-γ−/− IL-2Rα−/− mice, compared to single knock-out IL-2Rα−/− mice with respect to cholangitis or colitis. Furthermore, there was a significant increase in pathogenetic CD8+ T cells in the liver of IL-17A−/−IL-2Rα−/− mice. Our data suggest that while IL-17A plays a protective role in autoimmune cholangitis, it has a pro-inflammatory role in inflammatory bowel disease. These data take on particular significance in the potential use of anti-IL-17A therapy in humans with primary biliary cirrhosis.  相似文献   
99.
Prenatal di(2-ethylhexyl) phthalate (DEHP) exposure can produce reproductive toxicity in animal models. Only limited data exist from human studies on maternal DEHP exposure and its effects on infants. We aimed to examine the associations between DEHP exposure in utero and reproductive hormone levels in cord blood. Between 2002 and 2005, 514 pregnant women agreed to participate in the Hokkaido Study Sapporo Cohort. Maternal blood samples were taken from 23–35 weeks of gestation and the concentration of the primary metabolite of DEHP, mono(2-ethylhexyl) phthalate (MEHP), was measured. Concentrations of infant reproductive hormones including estradiol (E2), total testosterone (T), and progesterone (P4), inhibin B, insulin-like factor 3 (INSL3), steroid hormone binding globulin, follicle-stimulating hormone, and luteinizing hormone were measured from cord blood. Two hundred and two samples with both MEHP and hormones'' data were included in statistical analysis. The participants completed a self-administered questionnaire regarding information on maternal characteristics. Gestational age, birth weight and infant sex were obtained from birth records. In an adjusted linear regression analysis fit to all study participants, maternal MEHP levels were found to be associated with reduced levels of T/E2, P4, and inhibin B. For the stratified analyses for sex, inverse associations between maternal MEHP levels T/E2, P4, inhibin B, and INSL3 were statistically significant for males only. In addition, the MEHP quartile model showed a significant p-value trend for P4, inhibin B, and INSL3 decrease in males. Since inhibin B and INSL3 are major secretory products of Sertoli and Leydig cell, respectively, the results of this study suggest that DEHP exposure in utero may have adverse effects on both Sertoli and Leydig cell development in males, which agrees with the results obtained from animal studies. Comprehensive studies investigating phthalates'' exposure in humans, as well as their long-term effects on reproductive development are needed.  相似文献   
100.
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