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Chien-Te?Chou Hong-Ting?Lin Pai-An?Hwang Shang-Ta?Wang Cheng-Hong?Hsieh Deng-Fwu?HwangEmail author 《Amino acids》2015,47(4):735-744
The goal of the study is to investigate the preventive effect of taurine against arsenite-induced arrest of neuronal differentiation in N2a cells. Our results revealed that taurine reinstated the neurite outgrowth in arsenite-treated N2a cells. Meanwhile, arsenite-induced oxidative stress and mitochondrial dysfunction as well as degradation of mitochondria DNA (mtDNA) were also inhibited by co-treatment of taurine. Since oxidative stress and mitochondrial dysfunction is closely associated with endoplasmic reticulum (ER) stress, we further examined indicators of ER stress, 78 kDa glucose-regulated protein (GRP78), and C/EBP-homologous protein (CHOP) protein expression. The results demonstrated that taurine significantly reduced arsenite-induced ER stress in N2a cells. In the parallel experiment, arsenite-induced disruption of intracellular calcium homeostasis was also ameliorated by taurine. The proven bio-function of taurine preserved a preventive effect against deleteriously cross-talking between oxidative stress, mitochondria, and ER. Overall, the results of the study suggested that taurine reinstated neuronal differentiation by inhibiting oxidative stress, ER stress, and mitochondrial dysfunction in arsenite-treated N2a cells. 相似文献
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Stefanie Hartman Chen Jody L. Plank Smaranda Willcox Jack D. Griffith Tao-shih Hsieh 《PloS one》2014,9(1)
Although Blm and Top3α are known to form a minimal dissolvasome that can uniquely undo a double Holliday junction structure, the details of the mechanism remain unknown. It was originally suggested that Blm acts first to create a hemicatenane structure from branch migration of the junctions, followed by Top3α performing strand passage to decatenate the interlocking single strands. Recent evidence suggests that Top3α may also be important for assisting in the migration of the junctions. Using a mismatch-dHJ substrate (MM-DHJS) and eukaryotic Top1 (in place of Top3α), we show that the presence of a topoisomerase is required for Blm to substantially migrate a topologically constrained Holliday junction. When investigated by electron microscopy, these migrated structures did not resemble a hemicatenane. However, when Blm is together with Top3α, the dissolution reaction is processive with no pausing at a partially migrated structure. Potential mechanisms are discussed. 相似文献
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Direct cocktail analysis of drug discovery compounds in pooled plasma samples using liquid chromatography-tandem mass spectrometry 总被引:2,自引:0,他引:2
Hsieh Y Bryant MS Brisson JM Ng K Korfmacher WA 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2002,767(2):353-362
Direct plasma injection technology coupled with a LC-MS/MS assay provides fast and straightforward method development and greatly reduces the time for the tedious sample preparation procedures. In this work, a simple and sensitive bioanalytical method based on direct plasma injection using a single column high-performance liquid chromatography (HPLC) and tandem mass spectrometry (MS/MS) was developed for direct cocktail analysis of double-pooled mouse plasma samples for the quantitative determination of small molecules. The overall goal was to improve the throughput of the rapid pharmacokinetic (PK) screening process for early drug discovery candidates. Each pooled plasma sample was diluted with working solution containing internal standard and then directly injected into a polymer-coated mixed-function column for sample clean-up, enrichment and chromatographic separation. The apparent on-column recovery of six drug candidates in mouse plasma samples was greater than 90%. The single HPLC column was linked to either an atmospheric pressure chemical ionization (APCI) or electrospray ionization (ESI) source as a part of MS/MS system. The total run cycle time using single column direct injection methods can be achieved within 4 min per sample. The analytical results obtained by the described direct injection methods were comparable with those obtained by semi-automated protein precipitation methods within +/- 15%. The advantages and challenges of using direct single column LC-MS/MS methods with two ionization sources in combination of sample pooling technique are discussed. 相似文献
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Wei-Chih Su Wei-Yu Kao Tsung-Kun Chang Hsiang-Lin Tsai Ching-Wen Huang Yen-Cheng Chen Ching-Chun Li Yi-Chien Hsieh Hsing-Jung Yeh Chun-Chao Chang Jaw-Yuan Wang 《Bioscience reports》2021,41(1)
Despite the steadily increasing worldwide incidence of colorectal cancer (CRC), an effective noninvasive approach for early detection of CRC is still under investigation. The guaiac-based fecal occult blood test (FOBT) and fecal immunochemical test (FIT) have gained popularity as noninvasive CRC screening tests owing to their convenience and relatively low costs. However, the FOBT and FIT have limited sensitivity and specificity. To develop a noninvasive tool for the detection of CRC, we investigated the sensitivity, specificity, and accuracy of a stool DNA test targeting methylated syndecan-2 (SDC2), which is frequently methylated in patients with CRC. The present study enrolled 62 patients diagnosed as having stage 0-IV CRC and 76 healthy participants between July 2018 and June 2019 from two institutions. Approximately 4.5 g of stool sample was collected from each participant for detection of human methylated SDC2 gene. In total, 48 of 62 (77.4%) patients with CRC showed positive results, whereas 67 out of 76 (88.2%) healthy participants showed negative results. The area under the curve of the receiver operating characteristic curve constructed was 0.872 for discrimination between patients with CRC and healthy individuals. The present study highlights the potential of the fecal methylated SDC2 test as a noninvasive detection method for CRC screening with a relatively favorable sensitivity of 77.4%, a specificity of 88.2% and a positive predictive value of 84.2% compared with other available fecal tests. Further multicenter clinical trials comprising subjects of varied ethnicities are required to validate this test for the mass screening of patients with CRC. 相似文献
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Kun-Shan Cheng Yan-Chiou Liao Mu-Yuan Chen Tang-Ching Kuan Yi-Han Hong Li Ko Wen-Yeh Hsieh Chien-Liang Wu Ming-Ren Chen Chih-Sheng Lin 《International journal of biological sciences》2013,9(6):557-563
Ventricular septal defect (VSD) is the most common form of congenital heart diseases. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases involved in causal cardiac tissue remodeling. We studied the changes of circulating MMP-2 and MMP-9 activities in the patients with VSD severity and closure. There were 96 children with perimembranous VSD enrolled in this study. We assigned the patients into three groups according to the ratio of VSD diameter/diameter of aortic root (Ao). They were classified as below: Trivial (VSD/Ao ratio ≤ 0.2), Small (0.2 < VSD/Ao ≤ 0.3) and Median (0.3 < VSD/Ao) group. Plasma MMP-2 and MMP-9 activities were assayed by gelatin zymography.There was a significant higher MMP-2 activity in the VSD (Trivial, Small and Median) groups compared with that in Control group. The plasma MMP-9 activity showed a similar trend as the findings in MMP-2 activity. After one year follow-up, a significant difference in the MMP-9 activity was found between VSD spontaneous closure and non-closure groups. In conclusion, a positive trend between the severity of VSD and activities of MMP-2 and MMP-9 was found. Our data imply that MMP-2 and MMP-9 activities may play a role in the pathogenesis of VSD. 相似文献
50.
Muideen Tunbosun Olaiya Hung-Yi Chiou Jiann-Shing Jeng Li-Ming Lien Fang-I Hsieh 《PloS one》2013,8(10)