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111.
This study tested whether there were different expressions of gastric Lewis antigens between children and adults with Helicobacter pylori infection, and whether the difference was related to the infection outcome. About 68 dyspeptic children and 110 dyspeptic
adults were enrolled to check H. pylori infection, its colonization density, and the related histology. Gastric Lewis antigens b (Leb), x (Lex), and sialyl-Lewis x (sialyl-Lex) were immunohistochemically stained and scored for the intensity. The H. pylori-infected adults, but not the children, had a lower Leb intensity over the antrum (p = 0.019) but higher Leb intensity over the corpus (p = 0.001) than the non-infected ones. Over the antrum, both the H. pylori-infected children and adults had a lower Lex and higher sialyl-Lex intensity than those non-infected ones (p < 0.05). The H. pylori-infected adults had a higher bacterial density (p = 0.004) and Leb intensity (p = 0.016) over the corpus than the H. pylori-infected children. For the H. pylori-infected adults, but not children, the corpus had a higher Leb (p = 0.038) and lower Lex (p = 0.005) intensity than the antrum. Furthermore, the H. pylori-infected adults expressed a higher Leb and had a higher bacterial density than those with weak Leb (antrum, p < 0.001; corpus, p = 0.001). In conclusion, H. pylori infection is associated with the intensity change of Lewis antigen expressions in the stomach. The changes of gastric Lewis
antigen expressions are different between adults and children with H. pylori infection, which may exert different H. pylori colonization over the corpus between adults and children. 相似文献
112.
To know whether plasma zinc status is altered under acute hyperglycemic state, the interrelationships among plasma glucose,
insulin, and zinc concentrations during oral glucose tolerance test (OGTT) in obese individuals and their lean controls were
studied. Plasma glucose and insulin concentrations under fasting as well as those values in response to OGTT were significantly
higher in obese individuals than those in lean controls. On the other hand, the obese had lower fasting plasma zinc concentrations
compared to lean controls (13.5 vs 18.1 Μmol/L,p < 0.005). Under fasting, plasma zinc concentrations in overall individuals inversely correlated to their body mass index (BMI)
(r = -0.516), plasma glucose (r = -0.620), and plasma insulin (r = -0.510). However, there were no significant changes in plasma
zinc and copper values during OGTT in both obese individuals and lean controls. This study showed that plasma zinc values
had no changes during OGTT in obese individuals. The results also indicated that lower fasting plasma zinc concentrations
in obese individuals were not the short-term metabolic result. 相似文献
113.
Cooper AJ Sheu KF Burke JR Strittmatter WJ Gentile V Peluso G Blass JP 《Journal of neurochemistry》1999,72(3):889-899
At least eight neurodegenerative diseases, including Huntington disease, are caused by expansions in (CAG)n repeats in the affected gene and by an increase in the size of the corresponding polyglutamine domain in the expressed protein. A hallmark of several of these diseases is the presence of aberrant, proteinaceous aggregates in the nuclei and cytosol of affected neurons. Recent studies have shown that expanded polyglutamine (Qn) repeats are excellent glutaminyl-donor substrates of tissue transglutaminase, and that the substrate activity increases with increasing size of the polyglutamine domain. Tissue transglutaminase is present in the cytosol and nuclear fractions of brain tissue. Thus, the nuclear and cytosolic inclusions in Huntington disease may contain tissue transglutaminase-catalyzed covalent aggregates. The (CAG)n/Qn-expansion diseases are classic examples of selective vulnerability in the nervous system, in which certain cells/structures are particularly susceptible to toxic insults. Quantitative differences in the distribution of the brain transglutaminase(s) and its substrates, and in the activation mechanism of the brain transglutaminase(s), may explain in part selective vulnerability in a subset of neurons in (CAG)n-expansion diseases, and possibly in other neurodegenerative disease. If tissue transglutaminase is found to be essential for development of pathogenesis, then inhibitors of this enzyme may be of therapeutic benefit. 相似文献
114.
Yang HC Liang YJ Chen JW Chiang KM Chung CM Ho HY Ting CT Lin TH Sheu SH Tsai WC Chen JH Leu HB Yin WH Chiu TY Chern CL Lin SJ Tomlinson B Guo Y Sham PC Cherny SS Lam TH Thomas GN Pan WH 《PloS one》2012,7(3):e32907
Hypertension is a complex disorder with high prevalence rates all over the world. We conducted the first genome-wide gene-based association scan for hypertension in a Han Chinese population. By analyzing genome-wide single-nucleotide-polymorphism data of 400 matched pairs of young-onset hypertensive patients and normotensive controls genotyped with the Illumina HumanHap550-Duo BeadChip, 100 susceptibility genes for hypertension were identified and also validated with permutation tests. Seventeen of the 100 genes exhibited differential allelic and expression distributions between patient and control groups. These genes provided a good molecular signature for classifying hypertensive patients and normotensive controls. Among the 17 genes, IGF1, SLC4A4, WWOX, and SFMBT1 were not only identified by our gene-based association scan and gene expression analysis but were also replicated by a gene-based association analysis of the Hong Kong Hypertension Study. Moreover, cis-acting expression quantitative trait loci associated with the differentially expressed genes were found and linked to hypertension. IGF1, which encodes insulin-like growth factor 1, is associated with cardiovascular disorders, metabolic syndrome, decreased body weight/size, and changes of insulin levels in mice. SLC4A4, which encodes the electrogenic sodium bicarbonate cotransporter 1, is associated with decreased body weight/size and abnormal ion homeostasis in mice. WWOX, which encodes the WW domain-containing protein, is related to hypoglycemia and hyperphosphatemia. SFMBT1, which encodes the scm-like with four MBT domains protein 1, is a novel hypertension gene. GRB14, TMEM56 and KIAA1797 exhibited highly significant differential allelic and expressed distributions between hypertensive patients and normotensive controls. GRB14 was also found relevant to blood pressure in a previous genetic association study in East Asian populations. TMEM56 and KIAA1797 may be specific to Taiwanese populations, because they were not validated by the two replication studies. Identification of these genes enriches the collection of hypertension susceptibility genes, thereby shedding light on the etiology of hypertension in Han Chinese populations. 相似文献
115.
Wen-Chi Wei Sheng-Yen Lin Yi-Jyun Chen Chih-Chun Wen Chiung-Yao Huang Arulselvan Palanisamy Ning-Sun Yang Jyh-Horng Sheu 《Journal of biomedical science》2011,18(1):94
Background
Skin is the largest organ in the body, and is directly exposed to extrinsic assaults. As such, the skin plays a central role in host defense and the cutaneous immune system is able to elicit specific local inflammatory and systemic immune responses against harmful stimuli. 12-O-tetradecanoylphorbol-13-acetate (TPA) can stimulate acute and chronic inflammation and tumor promotion in skin. TPA-induced dermatitis is thus a useful in vivo pharmacological platform for drug discovery. In this study, the inhibitory effect of briarane-type diterpenes (BrDs) from marine coral Briareum excavatum on TPA-induced dermatitis and dendritic cell (DC) function was explored. 相似文献116.
117.
To investigate the failure of high-level production of hepatitis B viral (HBV) surface antigen (HBsAg), including three authentic forms, large (L), middle (M) and major/small (S) HBsAg, in Escherichia coli, we employed the high-expression vector pGEX containing the glutathione S-transferase-encoding gene (GST) to study HBsAg production. Different fragments of HBV DNA containing the entire pre-S1/pre-S2/S region (for L protein), or partial pre-S1, pre-S2, pre-S1/pre-S2 and pre-S2/S region (for M protein), were fused downstream from the GST gene, in order to obtain five plasmids which encode GST-HBsAg fusion proteins. SDS-PAGE analyses revealed that cells containing plasmids with a full-length S region (pGLS and pGMS) produced undetectable GST-HBsAg fusion proteins, in contrast to those cells harboring plasmids without the S region (pGS1, pGS2 and pGS1S2), which synthesized fusion proteins in 3–10% of the total cellular protein. Using an immunoblot method to screen HBsAg production in cells which harbored plasmids derived from exonuclease BAL 31-digested pGLS, we obtained eight positive clones. Nucleotide sequence analyses of plasmids from the positive clones revealed that termination, deletion or frameshift occurred at the regions encoding either the first or the third transmembrane domain of the major HBsAg. Correlation between the production level of GST-HBsAg fusion proteins and their constituent and arrangement of amino acids (aa) at the last 20 as among 15 clones suggested that the fusion protein ended with a longer stretch of or a higher ratio of hydrophobic as had a lower production in E. coli. 相似文献
118.
119.
120.
Lin SY Chen CH Ho HO Chen HH Sheu MT 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2007,859(1):141-146
A simple and improved HPLC method with fluorometric detection for simultaneous determination of dextromethorphan (DM) and its three metabolites (dextrorphan (DX), 3-methoxymorphinan (MM), 3-hydroxymorphinan (HM)) in human plasma was developed and validated. The method involved a simple and efficient extraction protocol using an n-heptane/ethyl acetate (1:1) solvent mixture that achieved recoveries of 70-90% with an insignificant interference from the plasma matrix. The analysis was performed on a phenyl column with isocratic elution, a mobile phase composed of 20% methanol, 30% acetonitrile, and 50% KH2PO4 buffer (10mM, with adding 0.02% of TEA; adjusted with phosphoric acid to pH 3.5), and a run time of only 15 min. Linear calibration curves were constructed in the concentration range of 1-200 nM for DM and its three metabolites. The lower limit of quantitation (LLOQ) in human plasma was 1 nM for each compound. The coefficient of variation and RSE% of the intraday and interday analyses for DM and its three metabolites all complied with USFDA requirements. This analytical method was preliminarily applied to determine the polymorphic functions of CYP2D6 and CYP3A4 in the metabolic pathway of DM to DX and then to HM. 相似文献