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Li-Yu Tsai

Publications and source records attributed to Li-Yu Tsai.

At least 19 recordsLinked to original sources
PubMed2006

Development of probe-based ultraweak chemiluminescence technique for the detection of a panel of four oxygen-derived free radicals and their applications in the assessment of radical-scavenging abilities of extracts and purified compounds from food and herbal preparations.

We report here the development of a probe-based ultraweak chemiluminescence (uwCL) method capable of detecting a panel of four oxygen-derived free radicals (ODFRs) including superoxide (O2-), hydrogen peroxide (H2O2), hydroxyl radical (*OH), and peroxyl radical (ROO*) using different probes specific for these radicals performed by the same uwCL analyzer. The selected radical-generating systems and their corresponding uwCL-probing emitters were validated. These ODFR-detecting systems were subsequently utilized by us to assess the radical-scavenging ability (RSA) of a variety of extracts and purified constituents derived from foods and herbal preparations. Our approach for assessing RSA for these constituents is based on the suppression of uwCL generated by each ODFR, and the degrees of inhibition have been shown to be dose-dependent. For this reason, the estimation of IC50 for each testing compound can be obtained from the curve constructed based on the percent of inhibitions of uwCL versus the concentrations of the compound tested. To illustrate the practical applications of our devised methodology, data for comparative studies of RSA activities of fermented extracts of Cordeceps sinensis, purified methylgallate isolated from Toona sinesis, resveratrol purified from grape seeds, plus epimedin C from the aerial part of the Epimedium plant (yinyanghuo) are to be presented.

Fermentation↗
PubMed2006

Interaction of genetic polymorphisms in cytochrome P450 2E1 and glutathione S-transferase M1 to breast cancer in Taiwanese woman without smoking and drinking habits.

P450 (CYP) and glutathione S-transferase (GST) are involved in the activation and detoxification of many potential carcinogens. Although, the interaction between environmental exposure and genetic polymorphisms of cytochrome P450 2E1 (CYP2E1) and glutathione S-transferase M1 (GSTM1) in breast cancer has been assessed, the gene-gene interactions between CYP2E1 and GSTM1 related to breast cancer have not been focused on and reported. We conducted a hospital-based case-control study to investigate whether the genetic interaction effects of CYP2E1 and GSTM1 modify the risk of developing breast cancer independent of the effect of cigarette smoking and alcohol consumption. Individuals with the C2/C2 genotype of CYP2E1 had a lower risk (OR = 0.24, 95% CI = 0.08-0.74) when compared with those with the C1/C1 genotype. However, there was no significant difference (OR = 1.05, 95% CI = 0.73-1.50) in the GSTM1 genotype frequency between the cases with breast cancer and that of the controls. When individuals with the genotype of C1/C1 or C1/C2 of CYP2E1 and the wild-type of GSTM1 were compared with those of C2/C2 of CYP2E1 and the null-type of GSTM1 however, we found a significantly increased risk (OR = 3.50, 95% CI = 1.01-16.55) in the breast cancer patients. Our findings indicated a gene-gene interaction between CYP2E1 and GSTM1 was accessible to developing breast cancer in Taiwanese women without the habits of cigarette smoking and alcohol consumption even though independent effects of CYP2E1 and GSTM1 were weak or non-significant and suggest that environmental carcinogen besides cigarette and alcohol consumption could induce breast cancer.

Alcohol Drinking↗
PubMed2006

Association between the apolipoprotein E genotypes and breast cancer patients in Taiwanese.

To display the association between the apolipoprotein E (APOE) genotypes and breast cancer patients, a cross sectional study including 291 patients and 148 controls was performed. The APOE genotypes were measured in all participants, and the pathological diagnosis, estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 (HER-2) among breast cancer patients were collected. The results showed the APOE allele frequency in breast cancer patients was 11.7% epsilon2 carriers, 74.6% epsilon3 carriers and 13.7% epsilon4 carriers, and there was no significant difference when they were compared with those of the control group (15.5% epsilon2 carriers, 74.3% epsilon3 carriers and 10.1% epsilon4 carriers; p=0.342). Among the patients in pre-menopause, showed a higher frequency of epsilon2 carriers had the cancer site on the left than that of the epsilon3 carriers (78.6% versus 40.3%; p=0.019). Among breast cancer patients, there was no significant association between the APOE genotypes and menopausal status, pathological diagnosis, estrogen receptor, progesterone receptor, and HER-2. Our findings demonstrated that the APOE genotypes were not associated with breast cancer patients, and epsilon2 allele tended to induce breast cancer on the left site among those patients in pre-menopause.

Adult↗
PubMed2006

The fractionated Toona sinensis leaf extract induces apoptosis of human ovarian cancer cells and inhibits tumor growth in a murine xenograft model.

OBJECTIVE: Aqueous extract from the leaves of Toona sinensis Roem. has been shown to have an anti-proliferative effect on human lung cancer cells. In this study, we analyzed the anti-cancer activity/effect of different extraction fractions of the extract from T. sinensis leaves on ovarian cancer cells. METHODS: Cell viability was determined by XTT cell proliferation assay and cell survival assay. Apoptotic effect was detected by morphological analysis and immunoblotting. Cell cycle effect was evaluated by flow cytometry analysis and immunoblotting. In vivo therapeutic effect was evaluated by the subcutaneous inoculation of SKOV3 cells in nude mice (Foxnlnu/Foxnlnu) model. RESULTS: TSL2 of T. sinensis was more cytotoxic than other fractions and exhibited selectivity for ovarian cancer cell lines. TSL2 arrested SKOV3 ovarian cancer cells at the G2/M phase and induced cancer cells go through apoptotic pathway. Ex vivo xenograft study of nude mice showed that intraperitoneal injection of TSL2 was able to suppress the proliferation of ovarian cancer cells without significant nephrotoxicity, liver toxicity, or bone marrow suppression.

Animals↗
PubMed2006

Selenium, iron, copper, and zinc levels and copper-to-zinc ratios in serum of patients at different stages of viral hepatic diseases.

Viral hepatic diseases, especially those induced by the hepatitis B virus, can progress into more serious pathological outcomes and eventually to hepatocellular carcinoma. A growing body of evidence indicates that many trace elements play important roles in a number of carcinogenic processes that proceed through various mechanisms. To examine the status of trace elements during the development of hepatic carcinoma, we determined the selenium, iron, copper, and zinc levels and copper-to-zinc ratios in the serum of patients at different stages of viral hepatic disease. We observed significant changes in the selenium, iron, copper, and zinc levels in the serum of patients having hepatocellular carcinoma, relative to those of healthy controls (p < 0.05). The mean serum copper level in patients with hepatocellular carcinoma was significantly higher than that of the control group. In contrast, the mean selenium, iron, and zinc levels in patients having hepatocellular carcinoma were significantly lower than those of the control group. In addition, the mean zinc level in the serum of patients with hepatic cirrhosis was significantly lower than that of the control group (p < 0.05). Moreover, we found markedly elevated Cu: Zn ratios (p < 0.05) in patients having hepatic cirrhosis or hepatocellular carcinoma. Our findings imply that the levels of some trace elements, such as selenium, iron, copper, and zinc, and Cu: Zn ratios, might serve as biomarkers for the increased severity of viral hepatic damage.

Adolescent↗
PubMed2006

Lipid peroxidation and antioxidative status in beta-thalassemia major patients with or without hepatitis C virus infection.

BACKGROUND: Information pertaining to the lipid peroxidation and antioxidative status of patients with beta-thalassemic major, with or without hepatitis C virus infection, has been scanty. METHODS: We report here the results of our efforts in the evaluation of lipid peroxidative status, antioxidants, and vitamin A, E and C levels in the sera of a group of patients (n=42) with transfusion-dependent beta-thalassemic major with or without HCV infection. RESULTS: Firstly, plasma thiobarbituric acid reactive substance, a lipid peroxidation product, in these patients was found to be increased significantly when compared to the disease-free controls (p<0.05). Conversely, levels of plasma vitamins A, E and C were all shown to be drastically reduced as compared to the disease-free controls (p<0.01). In parallel with these data, we also found that HCV infection did play some role in aggravating the depletion of plasma vitamin E and C levels in the beta-thalassemic patients. In contrast, HCV infection did not seem to alter the levels of reduced glutathione (GSH) as well as antioxidant enzyme activities including superoxide dismutase and GSH peroxidase. CONCLUSIONS: Taken together, our data indicate that excessive lipid peroxidation and a profound depletion of plasma vitamin A, E and C levels exist in patients with beta-thalassemic major. These data suggest that antioxidant supplementation to the patients for the purpose of alleviating the oxidative stress may be warranted.

Adolescent↗
PubMed2006

In vitro effects of arecoline on sperm motility and cyclooxygenase-2 expression.

Semen samples were obtained from 30 volunteers who had never consumed betel quid. Swim-up spermatozoa from the 30 seminal samples of non-betel quid chewers and also non-smokers, usually not exposed to passive smoking, were treated in vitro with arecoline at different concentrations to evaluate the action of these drugs on sperm motility. Highly motile sperms were collected and divided into 5 equal fractions. Four fractions were supplemented with various concentrations of arecoline and one as control. The study was carried out at time 0 and +1, +2, +3 and +4 hr of incubation. Sperm cells were also extracted and blotted with COX-2 antibody after arecoline treatment after 4 hr incubation. The sperm motility parameters, i.e., motility, average path velocity, curvilinear velocity, straight-line velocity and linearity, were significantly decreased after arecoline treatment. In vitro, arecoline induces the COX-2 expression of sperm cells in a dose-dependent manner. This is the first report to demonstrate that arecoline may mediate COX-2 expression in human sperms, resulting in inflammation response. This situation may act on the structure responsible for the flagellar motion and cause the reduction of sperm motility.

Adult↗
PubMed2005

Whey protein concentrate promotes the production of glutathione (GSH) by GSH reductase in the PC12 cell line after acute ethanol exposure.

Excessive ethanol consumption may increase the production of reactive oxygen species (ROS), which results in the damage of tissues, especially the neurons and glial cells in the central nervous system (CNS). The purpose of this study is to evaluate the effects of whey protein concentrate (WPC) on the glutathione (GSH) status after acute ethanol exposure in the pheochromocytoma (PC12) cell line. In this study, we assayed the cell viability, the percentage of lactate dehydrogenase released (% LDH released), the level of GSH, and the activity of GSH reductase (GRx). The results showed that with the supplement of WPC, the cell viability displayed no significant difference after acute exposure of ethanol in groups with or without ethanol treatment. The ethanol-induced cytotoxicity showed a slight decrease ,and the level of GSH showed a significant increase. The activity of GRx significantly increased when 0.1, 10mg/ml of WPC was supplied. In conclusion, these results suggest that WPC in a moderate concentration should be a precursor agent to promote the production of GSH and will enhance the antioxidant capacity in the PC12 cell line.

Animals↗
PubMed2005

Blood-brain barrier dysfunction occurring in mice infected with Angiostrongylus cantonensis.

Several indices were used to assess whether blood-brain barrier (BBB) damage occurs in neurological disorders. Dysfunction of the BBB was surmised to be involved in the pathological changes of eosinophilic meningitis caused by the infection of Angiostrongylus cantonensis. The mean concentration of protein and albumin in the cerebrospinal fluid (CSF) of infected mice gradually increased from days 0 to 18 after infection and then rapidly increased 21 days after infection. The concentrations of protein and albumin in the CSF of infected mice 15 days after infection were all significantly higher than those in uninfected mice (all P-values at least <0.05). Parallel with the increase in protein and albumin in the CSF, infected mice showed a gradual increase in their CSF/serum protein and albumin ratios. The increase became significant at days 21 and 18 after infection, respectively (P<0.01 and P<0.05, respectively). The higher the worm counts in the brain, the higher the CSF/serum albumin ratio was observed in infected mice at day 21 after infection (P<0.001). In addition, the ratios of the CSF/serum albumin were positively correlated with the worm counts in the brain (P<0.001). The total leukocyte and eosinophil counts were also positively correlated with ratios of CSF/serum albumin (P<0.01). The amount of Evans blue in the brain of mice 21 days after infection from peripheral blood via BBB became significantly increased than those in uninfected mice (P<0.001). Thus, the evidence of high concentrations of protein and albumin, high leukocyte counts in CSF, high ratio of CSF/serum protein and albumin, and high permeability of BBB show that dysfunction of the BBB occurred in mice infected with A. cantonensis.

Angiostrongylus↗
PubMed2005

Influence of withdrawal of statin treatment on proinflammatory response and fibrinolytic activity in humans: an effect independent on cholesterol elevation.

BACKGROUND: In addition to lowering lipid profile, statins have pleiotropic effects on improving vascular function. Changes of these pleiotropic effects and their relationship to lipid profile after withdrawal of statin treatment remained unclear. METHODS: We investigated the changes of lipid profile and plasma concentrations of human soluble vascular cell adhesion molecule-1 (sVCAM-1) and human tissue type plasminogen activator (tPA) after withdrawal of statin treatment. Twenty-two patients (14 F, 8 M, aged 63+/-13 years) with hypercholesterolemia were treated with atorvastatin (ATOR; 10 mg/day) for 12 weeks. Blood samplings for serum lipid and markers were collected before, after and withdrawal of statin treatment. RESULTS: The total cholesterol, LDL-cholesterol and sVCAM-1 (from 394.4+/-251.7 to 321.0+/-198.9 ng/ml, p<0.05) all decreased significantly and the tPA (from 9.47+/-3.57 to 11.62+/-3.99 ng/ml, p<0.05) increased significantly after atorvastatin treatment. During the following 3 days after withdrawal of atorvastatin, the total cholesterol and LDL-cholesterol did not show any significant change. However, the plasma sVCAM-1 significantly elevated on day 2 (from 321.0+/-198.9 to 371.2+/-220.4 ng/ml, p<0.05) and the plasma tPA significantly decreased on day 1 (from 11.62+/-3.99 to 10.52+/-3.55 ng/ml, p<0.05) and day 3 (from 11.62+/-3.99 to 10.27+/-3.69 ng/ml, p<0.05). Both the significant elevation of sVCAM-1 and decrease of tPA after withdrawal of atorvastatin treatment occurred within 3 days, while the serum cholesterol and LDL-chol levels did not have any significant change and were still within the therapeutic range. CONCLUSIONS: After 12 weeks of atorvastatin treatment, the beneficial pleiotropic effects can be demonstrated simultaneously with lowering the lipid profile. However, after withdrawal of atorvastatin, the beneficial pleiotropic effects are abrogated rapidly within days and are independent on elevation of serum cholesterol.

Aged↗
PubMed2005

Falsely low LDL-cholesterol concentrations and artifactual undetectable HDL-cholesterol measured by direct methods in a patient with monoclonal paraprotein.

INTRODUCTION: Multiple myeloma is a malignant immunoproliferative disorder with lipoprotein abnormalities. We report a case of falsely low concentrations of LDL-cholesterol (LDL-C) and artifactural undetectable HDL-cholesterol (HDL-C) as measured with direct methods in a patient of multiple myeloma with IgGkappa monoclonal gammapathy and significant hyperlipidemia. CASE REPORT: The patient had HDL-C and LDL-C concentrations in the 0.63-0.71 mmol/l and 2.22-2.36 mmol/l ranges, respectively, as measured by a traditional semi-quantitative electrophoresis method. The observation of falsely low concentrations of LDL-C and artifactural undetectable HDL-C might result in the mismanagement of patients of multiple myeloma with monoclonal gammapathy, because the LDL-C and HDL-C concentrations are positive and negative risk factors of cardiovascular diseases. CONCLUSIONS: Care must be taken when using the homogenous method for direct measurement of LDL-cholesterol and HDL-cholesterol in patients of multiple myeloma with monoclonal paraprotein.

Aged↗
PubMed2005

Superoxide anion radical, lipid peroxides and antioxidant status in the blood of patients with breast cancer.

BACKGROUND: Reactive oxygen species (ROS), including superoxide anion radical (O2(-)), plays an important role in carcinogenesis. The human body has developed different antioxidant systems to defend against free radical attacks. We investigated the changes of the antioxidant status in the blood of patients with breast cancer. METHODS: The O2(-) generation and the levels of malondialdehyde (MDA) were measured as an index of lipid peroxidation along with the examination of the activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GRx), the levels of reduced glutathione (GSH), oxidized glutathione (GSSG), and vitamins A, C, and E. RESULTS: The results showed that the levels of O2(-) and MDA, and the activities of antioxidant enzymes in the blood of the patients with breast cancer were significantly higher than the controls. However, the levels of vitamin C, GSH, GSSG and ratio of GSH/GSSG in the blood of the patients with breast cancer were significantly decreased compared to control subjects. CONCLUSIONS: Oxidative stress may be involved in breast cancer. The increased activities of erythrocyte antioxidant enzymes may be a compensatory upregulation in response to the increased oxidative stress.

Adult↗
PubMed2005

Early expression of heme oxygenase-1 in leukocytes correlates negatively with oxidative stress and predicts hepatic and renal dysfunction at late stage of sepsis.

Oxidative stress triggered by septic insult may be the major cause of multiple organ dysfunction syndrome (MODS) in intensive unit care patients. The inducible form of heme oxygenase-1 (HO-1) can be induced by cytokines, lipopolysaccharide, and reactive oxygen species during sepsis. These facts raise the question of whether the expression of HO-1 in leukocytes can indicate the level of oxidative stress of multiple organs in sepsis. Clinical peritonitis was simulated in an animal model by cecal ligation and puncture (CLP). The level of oxidative stress was examined by plasma lipid peroxidation (LPO). Liver function was analyzed by plasma aspartate aminotransferase, alanine aminotransferase, total bilirubin, and direct bilirubin. Lung function was evaluated by severity of edema. Renal function was measured by blood urea nitrogen and creatinine. The correlation between early HO-1 induction and LPO level or organ functional indicators of the same rat at late sepsis was analyzed by linear regression. The results showed that the protein content of HO-1 increased at 9 h after CLP, whereas expression of HO-1 mRNA in leukocytes was significantly increased (P < 0.01) at 6 h after CLP. Plasma level of LPO and the indices of hepatic, pulmonary, and renal function were significantly increased at 18 h after CLP. Moreover, highly negative correlations were observed between HO-1 mRNA expression at 6 h after CLP and level of LPO or severity of hepatic/renal dysfunction at 18 h after CLP. These results suggest that early HO-1 mRNA expression in leukocytes may represent oxidative stress and may predict the severity of liver and renal dysfunction during sepsis.

Alanine Transaminase↗
PubMed2005

Comparison of cardiac troponin I levels in serum and sodium-citrate plasma using the ACCESS 2 immunoassay.

The aim of this study was to determine if sodium-citrate plasma is a suitable substitute for serum for cardiac troponin I (cTnI) measurement using the Beckman ACCESS 2 immunoassay. Linear regression analysis of cTnI levels in paired serum and sodium-citrate plasma samples from 80 patients provided a y-intercept of -0.0193 and a slope of 1.044. The correlation was good [r=0.995; 95% confidence interval 1.017 to 1.068, p <0.0001]. The paired results were not significantly different by Student's t-test. Serum and sodium-citrate plasma appear to be interchangeable as samples for cTnI measurement using the ACCESS 2 assay. Furthermore, the use of plasma reduces the turnaround time and may avoid false positive cTnI results due to residual fibrin.

False Positive Reactions↗
PubMed2004

Effect of withdrawal of statin on C-reactive protein.

BACKGROUND: C-reactive protein is considered a risk factor for coronary artery disease. In addition to its lipid-lowering properties, statin decreases the level of C-reactive protein. Abrupt cessation of statin therapy during treatment could increase the incidence of cardiac events in patients with atherosclerotic heart disease. The changes of C-reactive protein after withdrawal of statin therapy are still unknown. METHODS: Twenty patients with hyperlipidemia received statin (atorvastatin, 10 mg/day) therapy for 3 months. The levels of lipid profiles and C-reactive protein were assessed before receiving the statin therapy, immediately after 3 months of therapy, and on the 3 consecutive days after withdrawal of statin treatment. RESULTS: After 3 months of statin therapy, the total cholesterol, low-density lipoprotein cholesterol (LDL-chol), and C-reactive protein were significantly reduced (264.94 +/- 16.23 vs. 183.44 +/- 16.34 mg/dl, 183.17 +/- 34.56 vs. 122.00 +/- 17.66 mg/dl, and 2,309.00 +/- 437.85 vs. 1,257.95 +/- 207.99 ng/ml, respectively). The level of C-reactive protein increased on the second day after withdrawal of statin therapy (2,590.14 +/- 1,045.05 vs. 1,257.95 +/- 207.99 ng/ml); however, the total cholesterol and LDL-chol did not increase during the 3-day period after withdrawal of statin therapy. CONCLUSIONS: The increase in the level of C-reactive protein after withdrawal of statin therapy may be a contributing factor to the increased incidence of cardiac events in patients who have abruptly stopped statin therapy.

Aged↗