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C C Yeh

Publications and source records attributed to C C Yeh.

At least 19 recordsLinked to original sources
PubMed2006

Comparison of the effects of thoracic epidural analgesia and i.v. infusion with lidocaine on cytokine response, postoperative pain and bowel function in patients undergoing colonic surgery.

BACKGROUND: Both thoracic epidural analgesia (TEA) and i.v. lidocaine were able to decrease postoperative pain and duration of ileus. We compared TEA and i.v. lidocaine (IV) regarding their effects on cytokines, pain and bowel function after colonic surgery. METHODS: Sixty patients were randomly allocated to one of the three groups. TEA group had lidocaine 2 mg kg(-1) followed by 3 mg kg(-1) h(-1) epidurally and an equal volume of i.v. normal saline. The IV group received the same amount of lidocaine i.v. and normal saline epidurally. The control group received normal saline via both routes. These regimens were started 30 min before surgery and were continued throughout. Blood cytokines were measured at scheduled times within 72 h. RESULTS: Both TEA and IV groups had better pain relief. The total consumptions using patient-controlled epidural analgesia were 81.6 (6.5), 55.0 (5.3) and 45.6 (3.9) ml (P<0.01) and the times of flatus passage were 50.2 (4.9), 60.2 (5.8) and 71.7 (4.7) h (P<0.01) in the TEA, IV and control groups, respectively. The TEA group exhibited the best postoperative pain relief and the least cytokine surge. The IV group experienced better pain relief and less cytokine release than the control group. CONCLUSIONS: The TEA lidocaine had better pain relief, lower opioid consumption, earlier return of bowel function and lesser production of cytokines than IV lidocaine during 72 h after colonic surgery; IV group was better than the control group.

Aged↗
PubMed2005

Adsorption and thermal reactions of alkanethiols on pt(111): Dependence on the length of the alkyl chain.

The adsorption and thermal decomposition of alkanethiols (R-SH, where R = CH3, C2H5, and C4H9) on Pt(111) were studied with temperature-programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) with synchrotron radiation. Dissociation of sulfhydryl hydrogen (RS-H) of alkanethiol results in the formation of alkanethiolate; the extent of dissociation at an adsorption temperature of 110 K depends on the length of the alkyl chain. At small exposure, all chemisorbed CH3SH, C2H5SH, and C4H9SH decompose to desorb hydrogen below 370 K and yield carbon and sulfur on the surface. Desorption of products containing carbon is observed only at large exposure. In thermal decomposition, alkanethiolate is proposed to undergo a stepwise dehydrogenation: R'-CH2S --> R'-CHS --> R'-CS, R' = H, CH3, and C3H7. Further decomposition of the R'-CS intermediate results in desorption of H2 at 400-500 K and leaves carbon and sulfur on the surface. On the basis of TPD and XPS data, we conclude that the density of adsorption of alkanethiol decreases with increasing length of the alkyl chain. C4H9SH is proposed to adsorb mainly with a configuration in which its alkyl group interacts with the surface; this interaction diminishes the density of adsorption of alkanethiols but facilitates dehydrogenation of the alkyl group.

Journal Article↗
PubMed2004

Inhibition of N-acetyltransferase activity and gene expression in human colon cancer cell lines by diallyl sulfide.

Diallyl sulfide (DAS) is one of the major components of garlic (Allium sativum) and is widely used in the world for food. In this study, DAS was selected for testing the inhibition of arylamine N-acetyltransferase (NAT) activity (N-acetylation of 2-aminofluorene) and gene expression (mRNA NAT) in human colon cancer cell lines (colo 205, colo 320 DM and colo 320 HSR). The NAT activity was examined by high performance liquid chromatography and indicated that a 24 h DAS treatment decreases N-acetylation of 2-aminofluorene in three colon (colo 205, 320 DM and colo 320 HSR) cancer cell lines. The NAT enzymes (protein) were analyzed by western blotting and flow cytometry and it indicated that DAS decreased the levels of NAT in three colon (colo 205, 320 DM and colo 320 HSR) cancer cell lines. The gene expression of NAT (mRNAT NAT) was determined by polymerase chain reaction (PCR), it was shown that DAS affect mRNA NAT expression in examined human colon cancer cell lines. This report is the first to demonstrate that DAS does inhibit human colon cancer cell NAT activity and gene expression.

Allyl Compounds↗
PubMed2004

Polymorphism of HLA-B27 in Taiwanese Chinese.

Heterogeneity of HLA-B27 is represented by a family of 24 closely related alleles/subtypes. Frequency and disease association of these alleles with spondyloarthropathies differ among ethnic groups. Accurate investigation of frequencies of alleles is often hindered by the size and demographic region of sample tested. With an ever-increasing number of B27 alleles being discovered, it is becoming imperative to establish disease association of each individual alleles and its biological importance. In a large number of normal healthy Taiwanese Chinese individuals (75,777) tested nationally, over a period of five years, in a single immunogenetics centre, we found additional B27 subtypes not revealed in a previous Taiwanese Chinese population study. The subtypes found in Taiwanese Chinese and the frequencies of each of the subtypes are reported.

Adolescent↗
PubMed2002

Berberine inhibited arylamine N-acetyltransferase activity and gene expression and DNA adduct formation in human malignant astrocytoma (G9T/VGH) and brain glioblastoma multiforms (GBM 8401) cells.

Studies have demonstrated that berberine exhibits the antineoplastic action in rat model. Rat glial tumor cells also have been shown to have N-acetyltransferase activity. In this study, we reported the effects of berberine on arylamine N-acetyltransferase (NAT) activity, gene expression, and DNA adduct formation in human brain tumor cell lines (G95/VGH and GBM 8401). The activity of NAT (N-acetylation of substrate) was measured and determined by high-performance liquid chromatography (HPLC) assaying for the amounts of acetylated 2-aminofluorene (AF) and nonacetylated AF. Human brain tumor cells (G9T/VGH and GBM 8401) were used for examining NAT activity and gene expression and AF-DNA adduct formation. NAT gene expression was determined by polymerase chain reaction (PCR) for the levels of mRNA NAT in both examined cells lines. The amounts of AF-DNA adducts were also determined and quantities by HPLC. The results demonstrated that NAT activity, levels of mRNA NAT1 and AF-DNA adduct formation in both examined cell were inhibited and decreased by berberine in a dose-dependent manner. The apparent values of Km and Vmax from NAT of both examined cells were also determined with or without berberine cotreatment. The data also indicated that berberine decreased the apparent values of Km and Vmax. These effects also indicate that berberine is a uncompetitive inhibitor.

Arylamine N-Acetyltransferase↗
PubMed2001

The Chinese medicine Bu-Zhong-Yi-Qi-Tang inhibited proliferation of hepatoma cell lines by inducing apoptosis via G0/G1 arrest.

Bu-Zhong-Yi-Qi-Tang (BZYQT), a Chinese herbal medicine, inhibited the proliferation of human hepatoma cell lines (Hep3B, HepG2 and HA22T) dose-dependently. The IC50s of BZYQT on the proliferation of Hep3B, HepG2 and HA22T were 432.5+/-31.8 microg/ml, 455.4+/-24.2 microg/ml, and 2284.3+/-77.2 microg/ml respectively on day 3. However, BZYQT did not significantly inhibit the proliferation of normal human hepatocytes (Chang liver, CCL-13) at the concentration under 5,000 microg/ml. Major compounds of BZYQT, including astragaloside IV, ginsenoside Rb1 and Rg1, saikosaponin a and c, and glycyrrhizin, have been identified. To investigate the key inhibitors of BZYQT. Hep3B cells were treated with BZYQT, individual major compounds of BZYQT, and mixture of major compounds in the same ratio as present in BZYQT. Significant inhibition of proliferation was detected in BZYQT and its major compounds mixture in a comparable level. Not any individual major compound examined could suppress the proliferation of Hep3B cells. This data indicated that there could be synergistic or additive effects of the ingredients in BZYQT. BrdU incorporation, cell cycle analysis and DNA fragmentation assay revealed that BZYQT suppressed the proliferation of hepatoma cells via G0/G1 cell cycle arrest and inhibition of DNA synthesis followed by apoptosis.

Animals↗
PubMed2001

p14(ARF) modulates the cytolytic effect of ONYX-015 in mesothelioma cells with wild-type p53.

ONYX-015 has been reported to kill selectively tumor cells lacking functional p53. Genetic alterations of INK4a/ARF locus, which is a predominant event in malignant pleural mesothelioma, may result in loss of p14(ARF) and subsequent disruption of p53 pathway in cancer cells. In the present study, ONYX-015 was able to kill three mesothelioma cell lines (H28, H513, and 211H) with wild-type p53 but lacking p14(ARF). In contrast, MS-1 mesothelioma cells, which expressed both p53 and p14(ARF), were resistant to ONYX-015. Introducing p14(ARF) gene into the H28 cell, a mesothelioma cell without p14(ARF) expression, significantly increased the resistance of this cell line to the cytolytic effect of ONYX-015. Our results suggest that human mesotheliomas with wild-type p53 yet lacking p14(ARF) are potential candidates for ONYX-015 therapy.

Adenovirus E1B Proteins↗
PubMed2001

DNA mismatch repair enzyme activity and gene expression in prostate cancer.

Microsatellite instability (MSI) of short repetitive sequences in human chromosomal DNA can result from defective DNA mismatch repair function in tumor cells. We hypothesize that DNA mismatch repair (MMR) activity is down-regulated during prostatic carcinogenesis. To test this hypothesis, MMR activities and mismatch repair-related genes were analyzed in five different prostate cancer cell lines. Our results demonstrate that MMR activities were decreased as compared to MMR proficient HeLa cells. Interestingly, LNCaP, PC-3 and DU145 had much lower MMR activities as compared to DUPro and TSUPr1. The MMR-related genes (hMLH1, hPMS1, hPMS2, hMSH2, hMSH3, hMSH6) showed mRNA transcripts in all prostate cancer cell lines. However, Western blotting showed decreased or absent hMLH1 protein expression in PC-3, DU145, DUPro and TSUPr1 cells. Similarly, the hMSH2 protein expression was low or absent in DU145 and LNCaP cells. This is the first report that demonstrates decreased MMR activities is associated with low expression of hMLH1, hMSH2 and other MMR-related proteins in prostate cancer.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Catalytic growth and characterization of gallium nitride nanowires.

The preparation of high-purity and -quality gallium nitride nanowires is accomplished by a catalytic growth using gallium and ammonium. A series of catalysts and different reaction parameters were applied to systematically optimize and control the vapor-liquid-solid (VLS) growth of the nanowires. The resulting nanowires show predominantly wurtzite phase; they were up to several micrometers in length, typically with diameters of 10-50 nm. A minimum nanowire diameter of 6 nm has been achieved. Temperature dependence of photoluminescence spectra of the nanowires revealed that the emission mainly comes from wurtzite GaN with little contribution from the cubic phase. Moreover, the thermal quenching of photoluminescence was much reduced in the GaN nanowires. The Raman spectra showed five first-order phonon modes. The frequencies of these peaks were close to those of the bulk GaN, but the modes were significantly broadened, which is indicative of the phonon confinement effects associated with the nanoscale dimensions of the system. Additional Raman modes, not observed in the bulk GaN, were found in the nanowires. The field emission study showing notable emission current with low turn-on field suggests potential of the GaN nanowires in field emission applications. This work opens a wide route toward detailed studies of the fundamental properties and potential applications of semiconductor nanowires.

Journal Article↗
PubMed2001

Loss of mismatch repair activity in simian virus 40 large T antigen-immortalized BPH-1 human prostatic epithelial cell line.

Simian virus 40 large T antigen (SVLTAg) has been used to immortalize cells; however, the mechanism leading to immortalization is still unclear. We hypothesize that DNA mismatch repair (MMR) activity is important during SVLTAg-induced immortalization. To test this hypothesis, we used the SVLTAg-immortalized cell line BPH-1 derived from human benign prostate epithelial cells to analyze MMR activity and the expression of MMR genes (hMLH1, hPMS1, hPMS2, hMSH2, hMSH3, and hMSH6). The results demonstrated that BPH-1 cells were deficient in repairing G:T, A:C, and G:G mispairs in bacteriophage M13mp2. Reverse-transcription polymerase chain reaction experiments indicated MMR genes (hMSH3, hMSH6, and hPMS1) were expressed at a low level in BPH-1 cells. In contrast, all six MMR genes were expressed in human benign prostate hyperplasia tissues. Downregulation of hMSH3, hMSH6, and hPMS1 genes is not a result of the hypermethylation mechanism because demethylation with 5-aza-2'-deoxycytidine did not restore expression of these genes. Although the hMLH1 gene is expressed in BPH-1 cells, western blotting and exon analyses demonstrated that hMLH1 was mutated and/or deleted in BPH-1 cells.

Adaptor Proteins, Signal Transducing↗
PubMed2001

Kinetics of acetyl coenzyme A: arylamine N-acetyltransferase from rapid and slow acetylator human benign prostatic hyperplasia tissues.

N-acetyltransferase (NAT) activity was determined in 40 human benign prostatic hyperplasia tissues using 2-aminofluorene (AF) and p-aminobenzoic acid (PABA) as substrates. These were then assayed by high performance liquid chromatography for determining the amounts of acetylated AF and PABA and non-acetylated AF and PABA. The activities (mean +/- SD) of AF-NAT from human benign prostatic hyperplasia tissues were divided into rapid (2.06 +/- 0.08 nmol/min per milligram protein), intermediate (1.25 +/- 0.26 nmol/min per milligram protein), and slow (0.58 +/- 0.30 nmol/min per milligram protein) acetylator groups. The activities (mean +/- SD) of PABA-NAT from human benign prostatic hyperplasia tissues were also divided into rapid (2.00 +/- 0.00 nmol/min per milligram protein), intermediate (1.25 +/- 0.18 nmol/min per milligram protein), and slow (0.48 +/- 0.29 nmol/min per milligram protein) acetylator groups. Kinetic constants for arylamine NAT activities were determined for each of these acetylator groups. Apparent differences in Km and Vmax for AF were found. Therefore, there seems to be a polymorphism in NAT activity with two rapid, five intermediate, and 33 slow acetylators among the 40 samples assayed. This is the first demonstration of acetyl CoA-arylamine NAT activity in human benign prostatic hyperplasia tissues.

4-Aminobenzoic Acid↗
PubMed2001

Microsomal monooxygenase activity in Tilapia (Oreochromis mossambicus) exposed to a bleached kraft mill effluent using different exposure systems.

Bleached kraft pulp and paper mill effluents (BKMEs) are known to have adverse effects on aquatic organisms. One of the effects of BKMEs is its ability to induce cytochrome P4501A activity in exposed fish. 7-Ethoxyresorufin O-deethylase (EROD) activity is the most common biomarker used to measure the mixed-function monooxygenase activity. In this study, Tilapia were exposed to BKMEs using different exposure systems and their hepatic EROD activity, as well as liver/somatic index (LSI), were determined. In the Phase I study, Tilapia treated with betaNF and a whole (100%) BKME using a static, non-renewal system exhibited statistically significant EROD induction, but LSI values were not altered. In the Phase II study, fish were either caged in the mill's fishpond with the whole effluent passing through or cultured in tanks receiving 100% of the BKME continuously using a flow-through system in the laboratory. Their EROD activities were then compared with the non-exposed fish (control). The EROD activities in both groups of fish were elevated significantly with the greatest induction being observed in the field-exposed group. The LSI values in all of the field-exposed fish were significantly greater than the control Tilapia. The EROD assay was sensitive in detecting biological changes in fish exposed to the BKME. Further studies are warranted to better understand the impacts of BKMEs on aquatic organisms in Taiwan.

Animals↗
PubMed2001

Hepatitis A virus infection in Taipei in 1999.

BACKGROUND AND PURPOSE: Hepatitis A is a disease that is heavily affected by sanitation status. Hepatitis A is much less prevalent compared with decades ago in Taiwan, as in many rapidly developing regions. Hepatitis A vaccine is still self-paid under the National Health Insurance program and is still not widely utilized by the general public in Taiwan. This seroepidemiologic study evaluated the prevalence of antihepatitis A virus (anti-HAV) seropositivity in Taipei in 1999. METHODS: A total of 1017 serum samples from healthy inhabitants in Taipei were examined for anti-HAV antibody by qualitative enzyme immunoassay. RESULTS: The overall seroprevalence rate was 25.2% (255/1013) in the nonvaccinated population. The seropositivity rate for anti-HAV antibody among children younger than 12 months old was 23.3%. The rates dropped to between 1% and 4.8% among subjects between 1 and 20 years of age. A markedly higher rate of 40% was observed in subjects aged between 20 and 30 years. The seropositivity rate in subjects aged 31 to 50 was 80%. More than 90% of subjects older than 50 years were seropositive. The vaccination rate was low (0.5%). CONCLUSION: Our findings indicate that Taipei is an area of intermediate endemicity for hepatitis A virus. To achieve better herd immunity, a more active approach to the adoption of hepatitis A vaccine is warranted.

Adolescent↗
PubMed2000

Culicoides arakawae (Diptera: Ceratopogonidae) population succession in relation to leucocytozoonosis prevalence on a chicken farm in Taiwan.

Leucocytozoonosis caused by Leucocytozoon caulleryi is a significant disease prevalent in open chicken houses of southern and eastern Asia. L. caulleryi is transmitted by Culicoides arakawae, a blood-sucking vector. Leucocytozoonosis prevalence is influenced by vector population succession. Thus this examination was performed on a farm to investigate vector population succession and leucocytozoonosis prevalence in experimental chicks and to obtain the ecology data for assessing the prevalence. The findings were as follows: (1) C. arakawae adults might be highly host specific because they were rarely discovered on cattle or pig farms, and none of the experimental chickens were infected by L. caulleryi on those farms. (2) Identifying and counting gorged and gravid C. arakawae to assess leucocytozoonosis prevalence is a practical strategy. The critical vector index should be 5.0 calculated by dividing the smallest vector mean from the prevalent period by the largest vector mean from the population not causing leucotocytozoonosis. (3) Taking vector means from three or more collections each month, should be the best assessment of leucocytozoonosis prevalence because C. arakawae succession appears to have a 3-week periodicity. Hopefully, these findings will contribute to assessing leucocytozoonosis prevalence.

Animals↗
PubMed2000

Cloning and characterization of human estrogen receptor beta promoter.

Estrogen receptors beta (ERbeta) belong to the nuclear receptor superfamily of ligand-dependent transcription factors that play critical roles in regulating genes involved in a wide array of biological processes. To investigate regulation of tissue-specific expression of ERbeta, we cloned and characterized a 2.1-kilobase 5'-flanking region of the human ERbeta gene. Two major transcription start sites were identified by primer extension and rapid amplification of 5'-cDNA end. The human ERbeta proximal promoter contains both TATA box and initiator element (Inr) and is GC-rich with a GC content of 65%. An Alu repeat sequence containing an ER-dependent transcription enhancer exists between -1416 and -1703. The full-length 5'-flanking sequence of ERbeta fused to a luciferase reporter exhibited functional promoter activity in ERbeta-positive TSUPr1 cell, but not in ERbeta-negative DU145 cells. In addition, DNase I protection assays of the proximal promoter showed unique protection patterns with nuclear extracts from TSUPr1 cells and ERbeta negative HeLa cells, suggesting presence of cell-specific trans-acting factors that mediate tissue/cell-specific ERbeta expression. Serial deletion analysis revealed that a 293-bp region encompassing the TATA box and Inr element possesses basal promoter activity.

Base Sequence↗
PubMed2000

Adenovirus-mediated p14(ARF) gene transfer in human mesothelioma cells.

BACKGROUND: The p14(ARF) protein encoded by the INK4a/ARF locus promotes degradation of the MDM2 protein and thus prevents the MDM2-mediated inhibition of p53. Homozygous deletion of the INK4a/ARF locus is common in human mesothelioma and may result in the loss of p14(ARF) and the inactivation of p53. We designed this study to evaluate the biologic and potential therapeutic roles of p14(ARF) expression in mesothelioma cells. METHODS AND RESULTS: We constructed Adp14, an adenoviral vector carrying human p14(ARF) complementary DNA, and used it to transfect human mesothelioma cell lines H28, H513, H2052, and MSTO-211H. Overexpression of p14(ARF) led to increased amounts of p53 and the p21(WAF) proteins and dephosphorylation of the retinoblastoma protein. The growth rate of mesothelioma cells was inhibited markedly by infection with Adp14 compared with mock infection or infection with a control adenovirus vector, AdCtrl. Overexpression of p14(ARF) induced G(1)-phase cell cycle arrest and apoptotic cell death. Cytotoxicity assays showed that Adp14 had a statistically significantly (P =.002) greater effect on colon cancer (HCT116) cell lines containing two copies of the wild-type p53 gene than on p53-null cells, suggesting that functional p53 is a critical determinant of p14(ARF)-mediated cytotoxicity. CONCLUSIONS: The transfection of p14(ARF) into mesothelioma cells led to the overexpression of p14(ARF), which resulted in G(1)-phase arrest and apoptotic cell death. These results suggest that this gene therapy-based approach may be of use in the treatment of mesothelioma.

Adenoviridae↗