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101.
Members of the EGF-CFC family facilitate signaling by a subset of TGFbeta superfamily ligands that includes the nodal-related factors and GDF1/VG1. Studies in mouse, zebrafish, and chick point to an essential role for EGF-CFC proteins in the action of nodal/GDF1 signals in the early establishment of the mesendoderm and later visceral left-right patterning. Antisense knockdown of the only known frog EGF-CFC factor (FRL1), however, has argued against an essential role for this factor in nodal/GDF1 signaling. To address this apparent paradox, we have identified two additional Xenopus EGF-CFC family members. The three Xenopus EGF-CFC factors show distinct patterns of expression. We have examined the role of XCR2, the only Xenopus EGF-CFC factor expressed in post-gastrula embryos, in embryogenesis. Antisense morpholino oligonucleotide-mediated depletion of XCR2 disrupts left-right asymmetry of the heart and gut. Although XCR2 is expressed bilaterally at neurula stage, XCR2 is required on the left side, but not the right side, for normal left-right patterning. Left-side expression of XNR1 in the lateral plate mesoderm depends on XCR2, whereas posterior bilateral expression of XNR1 does not, suggesting that distinct mechanisms maintain XNR1 expression in different regions of neurula-tailbud embryos. Ectopic XCR2 on the right side initiates premature right-side expression of XNR1 and XATV, and can reverse visceral patterning. This activity of XCR2 depends on its co-receptor function. These observations indicate that XCR2 has a crucial limiting role in maintaining a bistable asymmetry in nodal family signaling across the left-right axis.  相似文献   
102.
The hydroxamic acid analogues (2) of the natural product gelastatins (1) were prepared by 1 step conversion reaction. The synthetic analogues (2) showed potent enzymatic inhibitory activities against MMP-2, MMP-9, and TACE IC50's of 6, 23, and 28 nM, respectively. In addition, 2 were able to inhibit TNF-alpha production effectively in mice as well as in a macrophage cell line, RAW 264.7. The protective effect of 2 also was examined on LPS-induced acute septic shock model. The mechanism of TNF-alpha inhibition was examined by RT-PCR and Western blot analyses. The relation of TACE and alpha-secretase was examined using cellular alpha-secretase assays on IMR-32 and SH-SY5Y cell lines. The docking mode of 2 with the catalytic domain of TACE was illustrated to analyze the binding mode for the further analogue design.  相似文献   
103.
The natural history of hepatitis B virus (HBV) infection is probably related to host immune factors. Interferon-γ (IFN-γ) plays significant roles in immune defense. This study was undertaken to investigate the association between HBV infection and single nucleotide polymorphisms (SNPs) of IFN-γ, IFN-γ receptor (IFNGR)-1 and 2, and interferon regulatory factor (IRF)-1 genes. Between March 2002 and December 2002, 614 Korean patients were enrolled in two different groups: an HBV clearance group (n = 201), who were hepatitis B surface antigen (HBsAg) negative with antibodies to HBsAg and hepatitis B core antigen, and an HBV persistence group (n = 413), who were repeatedly HBsAg positive. We assessed polymorphisms in the IFN-γ gene at position +874, in the IFNGR-1 gene at positions −56 and +95, in the IFNGR-2 gene at the second position of codon 64 (Gln64Arg), and in the IRF-1 gene promoter (−410, −388), and the genotype distributions of the HBV clearance and persistence groups were compared. On the basis of unconditional logistic regression analysis with adjustment for age and sex, no statistically significant association with susceptibility to persistent HBV infection was observed with the IFN-γ, IFNGR-1 and 2, and IRF-1 gene polymorphisms under the codominant, dominant, and recessive models.  相似文献   
104.
Bacterial lipoproteins play an important role in bacterial pathogenesis and physiology. The genome of Campylobacter jejuni, a major foodborn pathogen, is predicted to contain over 20 lipoproteins. However, the functions of the majority of C. jejuni lipoproteins remain unknown. The Cj0090 protein is encoded by a lipoprotein operon composed of cj0089, cj0090, and cj0091. Here, we report the crystal structure of Cj0090 at 1.9 Å resolution, revealing a novel variant of the immunoglobulin fold with β‐sandwich architecture. The structure suggests that Cj0090 may be involved in protein‐protein interactions, consistent with a possible role for bacterial lipoproteins. Proteins 2012;. © 2012 Wiley Periodicals, Inc.  相似文献   
105.
In this study, we investigated the differences in calbindin D-28k (CB), calretinin, (CR) and parvalbumin (PV) immunoreactivity in the hippocampus of Zucker diabetic fatty (ZDF) rats and Zucker lean control (ZLC) rats. In addition, we observed the effects of hypothyroidism on the levels of immunoreactivity of these proteins in ZDF rats. For this study, 7-week-old ZDF rats were used, and methimazole treatment was continued for 5 weeks to induce hypothyroidism. The animals were sacrificed at 12 weeks of age. ZDF rats showed increased blood glucose levels compared to those in ZLC rats. Methimazole intervention significantly reduced total and free T3 levels, and it ameliorated the increase of blood glucose levels in ZDF rats. In ZLC rats, CB, CR, and PV immunoreactivity was detected in regions of the hippocampus proper. In vehicle-treated ZDF rats, CB, CR, and PV immunoreactivity was significantly decreased in the hippocampus. However, in the methimazole-treated rats, CB, CR, and PV immunoreactivity was significantly increased compared to that in the vehicle-treated rats. These results suggest that hypothyroidism ameliorated the diabetes-induced reduction of CB, CR, and PV immunoreactivity in the hippocampus.  相似文献   
106.
As angiogenesis plays important roles in tumor growth and metastasis, searching for antiangiogenic compounds is a promising tactic for treating cancers. Cafestol, a diterpene found mainly in unfiltered coffee, provides benefit through varied biological activity, including antitumorigenic, antioxidative, and anti-inflammatory effects. This study aimed to investigate the effects of cafestol on angiogenesis and to uncover the associated mechanism. We show that cafestol inhibits angiogenesis of human umbilical vascular endothelial cells. This inhibition affects the following specific steps of the angiogenic process: proliferation, migration, and tube formation. The inhibitory effects of cafestol are accompanied by decreasing phosphorylation of FAK and Akt and by a decrease in nitric oxide production. Overall, cafestol inhibits angiogenesis by affecting the angiogenic signaling pathway.  相似文献   
107.
Oh D  Lee Y  La B  Yeo J  Chung E  Kim Y  Lee C 《Molecular biology reports》2012,39(4):4083-4090
Genetic associations of fatty acid composition with exonic single nucleotide polymorphisms (SNPs) in the gene encoding fatty acid synthase (FASN) were examined using 513 Korean cattle. All five individual SNPs of g.12870 T>C, g.13126 T>C, g.15532 C>A, g.16907 T>C and g.17924 G>A were associated with a variety of fatty acid compositions and further with marbling score (P < 0.05). Their genotypes of CC, TT, AA, TT, and GG were associated with increased monounsaturated fatty acids and with decreased saturated fatty acids (P < 0.05). The genotypes at all the SNPs also increased marbling score (P < 0.05). Further genetic associations with fatty acid composition suggested that homozygous genotype with the haplotype of ATG at g.15532, g.16907, and g.17924 in a linkage disequilibrium block increased monounsaturated fatty acids and marbling score (P < 0.05). We concluded that the five exonic SNPs of g.12870, g.13126, g.15532, g.16907, and g.17924 in the FASN gene could change fatty acid contents. Their genotypes of CC, TT, AA, TT, and GG and haplotype of ATG at g.15532, g.16907, and g.17924 were recommended for genetic improvement of beef quality.  相似文献   
108.
The relationships are given between total length and wet weight, and between total length and standard length for 10 scorpionfishes from the south coast of Korea.  相似文献   
109.
Bacillus subtilis SC-8 is a Gram-positive bacterium displaying narrow antagonistic activity for the Bacillus cereus group. B. subtilis SC-8 was isolated from Korean traditional fermented-soybean food. Here we report the draft genome sequence of B. subtilis SC-8, including biosynthetic genes for antibiotics that may have beneficial effects for control of food-borne pathogens.  相似文献   
110.
Acinetobacter baumannii is a major cause of nosocomial infection worldwide. We report the draft genome sequence of A. baumannii AC12, a multidrug-resistant nosocomial strain with additional resistance to carbapenems and polymyxin. The genome data will provide insights into the genetic basis of antimicrobial resistance and its adaptive mechanism.  相似文献   
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