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71.
Polymorphisms in cytokine genes and risk of Helicobacter pylori infection among Jamaican children 总被引:2,自引:0,他引:2
Tseng FC Brown EE Maiese EM Yeager M Welch R Gold BD Owens M Cranston B Hanchard B El-Omar E Hisada M 《Helicobacter》2006,11(5):425-430
Background: Infection by Helicobacter pylori is often acquired during childhood. Recent studies suggest that inflammatory cytokines may play a role in susceptibility to, and disease phenotype caused by, H. pylori infection, but the association of host genetic variability with risk of H. pylori infection has not been studied in children. Methods: We investigated the relationship between the risk of H. pylori antibody positivity and cytokine gene polymorphisms among 199 two‐year‐old Jamaicans. H. pylori seropositivity was determined by a validated research enzyme‐linked immunosorbent assay. Real‐time Taqman® polymerase chain reaction was used to determine variants at 17 loci in 11 cytokine genes (IL1A, IL1B, IL2, TNF, TLR4, IL4, IL6, IL10, IL10RA, IL12A and IL13). We estimated the odds ratio and the 95% confidence interval for the association of genetic polymorphisms with H. pylori seropositivity, using logistic regression. Results: Forty (20.1%) of 199 children were seropositive. Children's H. pylori seropositivity correlated highly with maternal H. pylori seropositivity (OR = 7.98, 95% CI = 1.05–60.60, p = .02). Children carrying IL1A?889T had a lower risk of H. pylori positivity, compared to those carrying ?889C, with each T allele associated with 43% risk reduction (OR = 0.57, 95% CI = 0.33–0.99, p‐trend = .05). No other loci we examined were associated with the risk of H. pylori seropositivity. Conclusions: The IL1A?889 T allele, known to express a higher level of cytokine IL‐1α, is associated with a lower risk of H. pylori infection among Jamaican children. Our finding supports the hypothesis that an upregulation of pro‐inflammatory cytokines may protect against persistent H. pylori colonization. 相似文献
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Overexpression of ZAKβ in human osteosarcoma cells enhances ZAKα expression,resulting in a synergistic apoptotic effect 下载免费PDF全文
76.
Liu K Lepin EJ Wang MW Guo F Lin WY Chen YC Sirk SJ Olma S Phelps ME Zhao XZ Tseng HR Michael van Dam R Wu AM Shen CK 《Molecular imaging》2011,10(3):168-76, 1-7
Methods for tagging biomolecules with fluorine 18 as immuno-positron emission tomography (immunoPET) tracers require tedious optimization of radiolabeling conditions and can consume large amounts of scarce biomolecules. We describe an improved method using a digital microfluidic droplet generation (DMDG) chip, which provides computer-controlled metering and mixing of 18F tag, biomolecule, and buffer in defined ratios, allowing rapid scouting of reaction conditions in nanoliter volumes. The identified optimized conditions were then translated to bench-scale 18F labeling of a cancer-specific engineered antibody fragments, enabling microPET imaging of tumors in xenografted mice at 0.5 to 4 hours postinjection. 相似文献
77.
Tsai CT Chiang FT Chen WP Hwang JJ Tseng CD Wu CK Yu CC Wang YC Lai LP Lin JL 《Cell calcium》2011,49(1):1-11
Angiotensin II (AngII) has been implicated in the mechanism of atrial fibrillation (AF). There may be calcium-dependent pro-fibrillatory effect of AngII on atrial myocytes. We used cultured confluent HL-1 atrial myocyte monolayer with spontaneously propagated depolarization to study direct pro-fibrillatory effect of AngII and its molecular mechanism. AngII stimulation induced fibrillatory-like complex electrogram and calcium wave propagation. AngII shortened action potential duration and augmented calcium transient, thus increasing electrochemical gradient of forward-mode sodium-calcium exchanger (NCX) current and induced frequent irregular afterdepolarizations. AngII increased expression of sodium-calcium exchanger (NCX), further increasing calcium-membrane voltage coupling gain. The fibrillatory effect of AngII was attenuated by NCX blocker SEA0400 and NCX siRNA knockdown. AngII increased expression of L-type calcium channel and augmented calcium transient through PKC and CREB. The fibrillatory effect of AngII was also attenuated by PKC inhibitor chelerythrine and dominant negative form of CREB. In conclusions, AngII itself may electrically contribute to the mechanism of AF through increasing NCX expression and augmenting calcium transient, which is PKC and CREB dependent. Specific genetic knockdown of NCX attenuated calcium mediated afterdepolarization and complex electrogram. 相似文献
78.
Wang LY Tseng WC Wu TS Kaneko K Takayama H Kimura M Yang WC Wu JB Juang SH Wong FF 《Bioorganic & medicinal chemistry letters》2011,21(18):5358-5362
An efficient 1,3-dipolar cycloaddition method was performed for the synthesis of a series of monofluoro- and trifluoromethane-3,5-disubstituted 1,2,4-triazoles. This efficient cycloaddition method was to react hydrazonoyl hydrochlorides with a series of aldehydes in the presence of NEt(3) as catalytic basic agent to provide the corresponding product in 28-94%. Their growth inhibitory results against cancer cells indicated that some of the fluorine- and trifluoromethane-containing compounds could effectively inhibit the growth of NCI-H226 and T-cell leukemia (Jurkat) cells. Among the compounds, trifluoromethane-containing 1,2,4-triazoles possessed the five-membered ring groups on the C-5 position of the triazolic ring, including cyclopentyl, 3-furyl, 3-thienyl, and 2-pyrrolyl, possessed the significant inhibitory activity for NCI-H226 cancer cells. 相似文献
79.
The nuclear envelope of metazoans disassembles during mitosis and reforms in late anaphase after sister chromatids have well separated. The coordination of these mitotic events is important for genome stability, yet the temporal control of nuclear envelope reassembly is unknown. Although the steps of nuclear formation have been extensively studied in vitro using the reconstitution system from egg extracts, the temporal control can only be studied in vivo. Here, we use time-lapse microscopy to investigate this process in living HeLa cells. We demonstrate that Cdk1 activity prevents premature nuclear envelope assembly and that phosphorylation of the inner nuclear membrane protein lamin B receptor (LBR) by Cdk1 contributes to the temporal control. We further identify a region in the nucleoplasmic domain of LBR that inhibits premature chromatin binding of the protein. We propose that this inhibitory effect is partly mediated by Cdk1 phosphorylation. Furthermore, we show that the reduced chromatin-binding ability of LBR together with Aurora B activity contributes to nuclear envelope breakdown. Our studies reveal for the first time a mechanism that controls the timing of nuclear envelope reassembly through modification of an integral nuclear membrane protein. 相似文献
80.
Yu-Fen Tseng Chien-Chih Wang Shuen-Kuei Liao Ching-Kai Chuang Wei-June Chen 《Journal of biomedical science》2011,18(1):20
Japanese encephalitis (JE) virus is the most common cause of epidemic viral encephalitis in the world. The virus mainly infects
neuronal cells and causes an inflammatory response after invasion of the parenchyma of the brain. The death of neurons is
frequently observed, in which demyelinated axons are commonly seen. The mechanism that accounts for the occurrence of demyelination
is ambiguous thus far. With a mouse model, the present study showed that myelin-specific antibodies appeared in sera, particularly
in those mice with evident symptoms. Meanwhile, specific T cells proliferating in response to stimulation by myelin basic
protein (MBP) was also shown in these mice. Taken together, our results suggest that autoimmunity may play an important role
in the destruction of components, e.g., MBP, of axon-surrounding myelin, resulting in demyelination in the mouse brain after infection with the JE virus. 相似文献