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111.
The role of luteinizing hormone (LH) and LH-releasing hormone (LH-RH) in the maintenance of early pregnancy in rats was studied. Serum levels of progesterone (P) and LH were measured daily in untreated pregnant rats from Day 4 through parturition. Serum levels of P and LH were determined on Days 11 and 15 of pregnancy in animals treated with antisera to LH (LH-A/S) and to LH-RH (LH-RH-A/S) on Days 8-10. Serum levels of P peaked on Days 7 and 16 in untreated animals, after which they declined sharply just before delivery. Serum LH fluctuated between 30-160 ng/ml during pregnancy but did not exhibit any distinctive peaks. Treatment with .2 ml LH-A/S on Days 8-10 reduced serum P to virtually undetectable levels on Day 11, and only a slight recovery was evident on Day 15. Lower doses of LH-A/S had no effect. Administration of 1.3 ml LH-RH-A/S had no effect on serum levels of P or LH, and did not impede fetal development. The results indicate that LH is essential to the luteotropic complex of early pregnancy in the rat, and also that LH-RH-A/S can maintain to some extent basal levels of P and LH during early pregnancy. 相似文献
112.
Upasana Shukla Tomoko Hatani Kenji Nakashima Kazuhiro Ogi Kiyonao Sada 《The Journal of biological chemistry》2009,284(49):33719-33728
Adaptor protein c-Abl SH3 domain-binding protein-2 (3BP2, also referred to SH3BP2) regulates immune receptor-mediated signal transduction. In this report we focused on the molecular mechanism of 3BP2 function in B cell receptor (BCR) signaling. Engagement of BCR induces tyrosine phosphorylation of 3BP2. Genetic analysis demonstrated that Syk is critical for BCR-mediated tyrosine phosphorylation of 3BP2. Mutational analysis of 3BP2 revealed that both Tyr183 and Src homology 2 (SH2) domain are necessary for 3BP2-mediated BCR-induced activation of nuclear factor of activated T cells (NFAT). Point mutation of Tyr183 or Arg486 in the SH2 domain of 3BP2 diminished BCR-mediated tyrosine phosphorylation of 3BP2. Endogenous 3BP2 forms a complex with tyrosine-phosphorylated cellular signaling molecules. Peptide binding experiments demonstrated that only phosphorylated Tyr183 in 3BP2 could form a complex with the SH2 domain(s) of phospholipase Cγ2 and Vav1 from B cell lysates. These interactions were represented by using bacterial glutathione S-transferase-phospholipase Cγ2 or -Vav1 SH2 domain. Furthermore, pulldown and Far Western experiments showed that the 3BP2-SH2 domain directly binds to B cell linker protein (BLNK) after BCR stimulation. These results demonstrated that 3BP2 induces the protein complex with cellular signaling molecules through phosphorylation of Tyr183 and SH2 domain leading to the activation of NFAT in B cells. 相似文献
113.
Akiko Sumi Jun Akiba Sachiko Ogasawara Masamichi Nakayama Yoriko Nomura Makiko Yasumoto Sakiko Sanada Osamu Nakashima Toshi Abe Hirohisa Yano 《PloS one》2015,10(3)
Aim
Des-γ-carboxyprothrombin (DCP) has been used as a tumor marker for hepatocellular carcinoma (HCC). Recently the DCP/NX-DCP ratio, calculated by dividing DCP by NX-DCP, has been reported useful in detecting HCC. The purpose of this study is to clarify the significance of DCP and NX-DCP expression in HCC tissues.Methods
HCC and non-HCC tissue samples were obtained from 157 patients and were immunohistochemically examined for DCP and NX-DCP expression using anti-DCP antibody and anti-NX-DCP antibody. DCP and NX-DCP expression scores were calculated by multiplying staining intensity grade by percentage of stained area. Serum DCP and NX-DCP levels were determined in 89 patients. We evaluated the relationship between tumor expression, serum level, and pathomorphological findings.Results
Intrahepatic metastasis (im) was significantly more frequent in cases with high DCP expression than in cases with low DCP expression. High NX-DCP expression was associated with significantly lower histological grade, and less frequent im or portal vein invasion (vp) than low NX-DCP expression. Serum DCP was correlated with DCP expression, but serum NX-DCP was not correlated with NX-DCP expression. DCP-positive (≥40 mAU/L), NX-DCP-positive (≥90 mAU/L), and DCP/NX-DCP ratio-positive (≥1.5) cases were associated with significantly larger tumor size and more frequent vp than negative cases. DCP was rarely expressed, but NX-DCP was frequently expressed in non-cancerous liver tissues. Patients with NX-DCP expression-negative tumors showed a lower survival rate than those with NX-DCP expression-positive tumors (p = 0.04), whereas the survival in serum NX-DCP-positive cases was lower than that of serum negative cases (p = 0.02).Conclusions
DCP and NX-DCP were produced in HCC tissues, but differed in expression level and biological properties. DCP expression, serum DCP or NX-DCP level, and DCP/NX-DCP ratio were closely related to malignant properties of HCC. 相似文献114.
115.
Muto S Miyoshi H Nishikawa H Nakashima H 《Biochemical and biophysical research communications》2006,348(4):1436-1442
Coxsackievirus B1 (CVB1) 2A proteinase (2A(pro)) is a cysteine proteinase that cleaves the viral monocistronic polyprotein between the C-terminus of the VP1 region and the N-terminus of the 2A region, and also shuts off translational initiation in host cells by cleavage of eukaryotic initiation factor 4G (eIF4G) isoforms. We expressed in Escherichia coli a series of fusions in which various C-terminal fragments of VP1 were linked to the N-terminus of 2A(pro), and we also employed site-directed mutagenesis to introduce mutations of several amino acid residues. Our results showed that the presence of the C-terminal three amino acid residues of VP1 at the N-terminus of 2A(pro) is sufficient for specific self-cleavage between VP1 and 2A(pro) to generate mature 2A(pro), but the P4 amino acid also plays an important role. We further found that 2A(pro) cleaves the amino acid sequence Leu-Val-Pro-Arg-( *)Gly-Ser (LVPRGS motif), which is the target sequence of thrombin. 相似文献
116.
Shinji Hama Ayumi Yoshida Kazunori Nakashima Hideo Noda Hideki Fukuda Akihiko Kondo 《Applied microbiology and biotechnology》2010,87(2):537-543
The cell surface engineering system, in which functional proteins are genetically displayed on microbial cell surfaces, has
recently become a powerful tool for applied biotechnology. Here, we report on the surfactant modification of surface-displayed
lipase to improve its performance for enzymatic synthesis reactions. The lipase activities of the surfactant-modified yeast
displaying Rhizopus oryzae lipase (ROL) were evaluated in both aqueous and nonaqueous systems. Despite the similar lipase activities of control and
surfactant-modified cells in aqueous media, the treatment with nonionic surfactants increased the specific lipase activity
of the ROL-displaying yeast in n-hexane. In particular, the Tween 20-modified cells increased the cell surface hydrophobicity significantly among a series
of Tween surfactants tested, resulting in 8–30 times higher specific activity in organic solvents with relatively high log
P values. The developed cells were successfully used for the enzymatic synthesis of phospholipids and fatty acid methyl esters
in n-hexane, whereas the nontreated cells produced a significantly low yield. Our results thus indicate that surfactant modification
of the cell surface can enhance the potential of the surface-displayed lipase for bioconversion. 相似文献
117.
Organic pollution in eutrophic river water dammed by estuary weirs was studied in the Shin and Kasuga rivers of the Shikoku
region, Japan. Both rivers are located in a low-precipitation region of Japan. The investigation was performed at intervals
of 3–14 days from 12 July 2002 to 13 July 2003. The annual averages of chlorophyll a concentration were approximately 150 and 40 μg L−1 in the Shin and Kasuga rivers, respectively. The concentration often exceeded 500 μg L−1 in the Shin River in winter. Dissolved oxygen saturation exhibited marked variation. High and low values, i.e., >150% in
the surface water layer and 0% in the bottom water layer, were occasionally observed. Dissolved methane concentrations >2,000 nM
were often observed from spring to fall. In both rivers, the serious organic substance pollution was confirmed through 1 year. 相似文献
118.
119.
Targeted deletion of AIF decreases mitochondrial oxidative phosphorylation and protects from obesity and diabetes 总被引:8,自引:0,他引:8
Pospisilik JA Knauf C Joza N Benit P Orthofer M Cani PD Ebersberger I Nakashima T Sarao R Neely G Esterbauer H Kozlov A Kahn CR Kroemer G Rustin P Burcelin R Penninger JM 《Cell》2007,131(3):476-491
Type-2 diabetes results from the development of insulin resistance and a concomitant impairment of insulin secretion. Recent studies place altered mitochondrial oxidative phosphorylation (OxPhos) as an underlying genetic element of insulin resistance. However, the causative or compensatory nature of these OxPhos changes has yet to be proven. Here, we show that muscle- and liver-specific AIF ablation in mice initiates a pattern of OxPhos deficiency closely mimicking that of human insulin resistance, and contrary to current expectations, results in increased glucose tolerance, reduced fat mass, and increased insulin sensitivity. These results are maintained upon high-fat feeding and in both genetic mosaic and ubiquitous OxPhos-deficient mutants. Importantly, the effects of AIF on glucose metabolism are acutely inducible and reversible. These findings establish that tissue-specific as well as global OxPhos defects in mice can counteract the development of insulin resistance, diabetes, and obesity. 相似文献
120.