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41.
42.
A molecular phylogenetic survey was conducted using mtDNA sequences of 12S and 16S rRNA, and cyt-b genes to examine taxonomic relationships among populations of the Pan-Oriental microhylid, Microhyla ornata, from India, Bangladesh, Thailand, Laos, China, Taiwan, and the Ryukyu Archipelago of Japan. Two discrete clades are recognized within this species, one consisting of populations from India and Bangladesh, and the other encompassing the remaining populations. In the latter clade, populations from the Ryukyu Archipelago are clearly split from the rest (populations from Taiwan and the continent) with considerable degrees of genetic differentiations. Each of the three lineages is judged to represent a good species, and the name Microhyla ornata is restricted to the South Asian populations. For the populations from Taiwan and a wide region from China to Southeast Asia, the name Microhyla fissipes should be applied, whereas the Ryukyu populations are most appropriately referred to as Microhyla okinavensis, although further substantial genetic differentiations are recognized among some island group populations within this last species.  相似文献   
43.
In obesity, levels of tumor necrosis-factor α (TNFα) are well known to be elevated in adipose tissues or serum, and a high-fat diet (HFD) reportedly increases TNFα expression in the hypothalamus. The expression levels of hypothalamic protein tyrosine phosphatase 1B (PTP1B), a negative regulator of leptin and insulin signaling, are also elevated by HFD, and several lines of evidence support a relationship between TNFα and PTP1B. It remains unclear however how TNFα acts locally in the hypothalamus to regulate hypothalamic PTP1B expression and activity. In this study, we examined whether TNFα can regulate PTP1B expression and activity using rat hypothalamic organotypic cultures. Incubation of cultures with TNFα resulted in increases in mRNA expression, protein levels and activity of PTP1B in a dose- and time-dependent manner, respectively compared with controls. TNFα-induced PTP1B protein levels were not influenced by co-incubation with the sodium channel blocker tetrodotoxin, indicating that the action of TNFα is independent of action potentials. TNFα also increased phosphorylation of p65, a subunit of nuclear factor-κB (NFκB), in a dose- and time-dependent manner. While incubation with inhibitors of NFκB did not affect basal levels of either p65 phosphorylation or PTP1B expression, it markedly suppressed both TNFα-induced p65 phosphorylation and PTP1B expression to almost basal levels. These data suggest that TNFα acts on the hypothalamus to increase hypothalamic PTP1B expression and activity via the NFκB pathway, and that TNFα-mediated induction of NFκB in the hypothalamus may cause leptin and insulin resistance in the hypothalamus by increasing hypothalamic PTP1B activity.  相似文献   
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45.
The sericulture industry plays a very important role in our national economy. Silkworm (Bombyx mori) is always regarded as a model animal and biological reactor. There have been detailed studies on the structure, expression and control and molecular evolution of silk genes. However, few, if any, reports are available on the localization of structural genes in silkworm by molecular cytogenetics. The present experiment has tentatively localized theFib-H gene at the distal end of the 25th linkage group, namely at the 25-0.0 position, and verified thatFib-H has only one locus, thus providing a temporary solution to the problem about its localization.  相似文献   
46.
A cDNA (cNPK2) that encodes a protein of 518 amino acids was isolated from a library prepared from poly(A)+ RNAs of tobacco cells in suspension culture. The N-terminal half of the predicted NPK2 protein is similar in amino acid sequence to the catalytic domains of kinases that activate mitogen-activated protein kinases (designated here MAPKKs) from various animals and to those of yeast homologs of MAPKKs. The N-terminal domain of NPK2 was produced as a fusion protein in Escherichia coli, and the purified fusion protein was found to be capable of autophosphorylation of threonine and serine residues. These results indicate that the N-terminal domain of NPK2 has activity of a serine/threonine protein kinase. Southern blot analysis showed that genomic DNAs from various plant species, including Arabidopsis thaliana and sweet potato, hybridized strongly with cNPK2, indicating that these plants also have genes that are closely related to the gene for NPK2. The structural similarity between the catalytic domain of NPK2 and those of MAPKKs and their homologs suggests that tobacco NPK2 corresponds to MAPKKs of other organisms. Given the existence of plant homologs of an MAP kinase and tobacco NPK1, which is structurally and functionally homologous to one of the activator kinases of yeast homologs of MAPKK (MAPKKKs), it seems likely that a signal transduction pathway mediated by a protein kinase cascade that is analogous to the MAP kinase cascades proposed in yeasts and animals, is also conserved in plants.  相似文献   
47.
A series of tetrahydroisoquinoline derivatives were designed, synthesized, and evaluated for their potential as novel orally efficacious retinoic acid receptor-related orphan receptor-gamma t (RORγt) inverse agonists for the treatment of Th17-driven autoimmune diseases. We carried out cyclization of the phenylglycinamide core by structure-based drug design and successfully identified a tetrahydroisoquinoline carboxylic acid derivative 14 with good biochemical binding and cellular reporter activity. Interestingly, the combination of a carboxylic acid tether and a central fused bicyclic ring was crucial for optimizing PK properties, and the compound 14 showed significantly improved PK profile. Successive optimization of the carboxylate tether led to the discovery of compound 15 with increased inverse agonistic activity and an excellent PK profile. Oral treatment of mice with compound 15 robustly and dose-dependently inhibited IL-17A production in an IL23-induced gene expression assay.  相似文献   
48.

Background

The reports of pregnancy after total gastrectomy for gastric cancer are rare.

Case presentation

We report a case of a 35-year-old woman, gravida 0, para 0, who became pregnant and delivered a baby 2?years and 6?months after laparoscopic-assisted total gastrectomy for early gastric cancer. Postoperatively, she showed a good progress during the follow-up and was continuously taking oral iron supplement and administered with methylcobalamin intramuscular injection. Two years after gastrectomy, she became pregnant. During the pregnancy, she kept taking iron and vitamin B12 supplementation and had a good course of pregnancy and a normal delivery. However, 2?months after the delivery, liver dysfunction was detected via blood examination. The patient switched from exclusive breastfeeding to combined feeding with formula, and her laboratory results returned to normal. During 10?years of follow-up after the delivery, the patient was in good condition without any recurrence and nutritional deficiencies, and her child had thrived.

Conclusions

Careful monitoring and management of iron and vitamin deficiencies are essential during pregnancy and the lactation periods for patients who previously underwent total gastrectomy. During the lactation period, a combination of formula and breastfeeding provides maternal and fetal nutritional support.
  相似文献   
49.
Zhao P  Xia Q  Li J  Fujii H  Banno Y  Xiang Z 《The protein journal》2007,26(5):349-357
Hemolymph chymotrypsin inhibitor 9 (CI-9) from the hemolymph of the silkworm, Bombyx mori, was purified by ammonium sulfate precipitation, Butyl Toyopearl hydrophobic chromatography, gel filtration through Sephadex C-50 and chymotrypsin-sepharose 4B affinity chromatography. Checked by Native PAGE and SDS-PAGE in combination with silver staining, the final preparation appeared homogeneous. In tricine SDS-PAGE, CI-9 displayed a molecular weight of 7.5 kD, which was determined to be 7167 Da with the Voyager TOFMass analyser. The pI value for CI-9, revealed by 2D-PAGE (two-dimensional polyacrylamide gel electrophoresis), was 4.3. CI-9 exhibited inhibitory activity at a temperature as high as 100°C and a stability against a wide range of pH (1–12). In N-terminal amino-acid analysis of CI-9, 40 amino acid residues were obtained. The C-terminal 22 amino acid residues were deduced by subsequently cloned cDNA and genomic fragments. MW and pI of CI-9 were predicted to be 7170.98 Da and 4.61, respectively, on the website. Its low molecular weight, high stability, conserved active site and Kunitz domain showed that CI-9 is a Kunitz-type CI. The difference of sequence and pI between CI-9 and other Kunitz type CIs indicated that it is a novel chymotrypsin inhibitor.  相似文献   
50.
Dietary carotenoids are absorbed in the intestine and delivered to various tissues by circulating lipoproteins; however, the mechanism underlying selective delivery of different carotenoid species to individual tissues remains elusive. The products of the Yellow cocoon (C) gene and the Flesh (F) gene of the silkworm Bombyx mori determine the selectivity for transport of lutein and β-carotene, respectively, to the silk gland. We previously showed that the C gene encodes Cameo2, a CD36 family member, which is thought to function as a transmembrane lipoprotein receptor. Here, we elucidated the molecular identity of the F gene product by positional cloning, as SCRB15, a paralog of Cameo2 with 26% amino acid identity. In the F mutant, SCRB15 mRNA structure was severely disrupted, due to a 1.4 kb genomic insertion in a coding exon. Transgenic expression of SCRB15 in the middle silk gland using the binary GAL4-UAS expression system enhanced selective β-carotene uptake by the middle silk gland, while transgenic expression of Cameo2 enhanced selective lutein uptake under the same GAL4 driver. Our findings indicate that divergence of genes in the CD36 family determines the selectivity of carotenoid species uptake by silk gland tissue and that CD36-homologous proteins can discriminate among carotenoid species.  相似文献   
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