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S H Yang

Publications and source records attributed to S H Yang.

136 records · Page 8Linked to original sources
PubMedDate not supplied

Levels of PCDDs and PCDFs in two kinds of fast foods in Korea.

We initiated an attempt to gather preliminary Korean fast food data on the concentrations, whole weight and international toxic equivalent (TEQ), in two kinds of fast foods, hamburger and fried chicken. The levels of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzofurans (PCDDs/PCDFs) in hamburgers are detected to be lower than in fried chickens. Total TEQ level of PCDDs in fried chicken is 47.45 times higher than in hamburger. In case of PCDFs, it is 48.61 times. Even though these are compared to the only one brand and three samples each, we think that these high levels of PCDDs/PCDFs in fried chicken are very important data because of the potentially increasing daily intake. If we continue to survey for PCDDs/PCDFs in fast foods more even, especially fried chicken, these data will be useful to calculate the estimated daily intake of TEQ levels of PCDDs/PCDFs in Korea.

Benzofurans↗
PubMedDate not supplied

PCDD and PCDF exposures in workers and controls living near an industrial waste incinerator.

This study measured the levels of 17 congeners of PCDDs/PCDFs in serum to compare the levels between potentially exposed workers at an industrial waste incinerator and any residents with no known exposures. The 1,2,3,6,7,8- and 1,2,3,7,8,9-HxCDD were detected in serum of workers but in controls. Likewise, 1,2,3,7,8-PeCDF, 1,2,3,6,7,8- and 1,2,3,7,8,9-HxCDF were detected only in serum of workers. The international toxic equivalent (TEQ) levels of PCDDs/PCDFs in sera of workers are much higher than in controls. Among PCDDs, the proportion of total concentration and TEQ level is dominated predominantly by 1,2,3,6,7,8- and 1,2,3,7,8,9-HxCDD. We need extensive studies to estimate human exposure and are continuing this investigation.

Adult↗
PubMedDate not supplied

Ischemic bile duct injury as a serious complication after transarterial chemoembolization in patients with hepatocellular carcinoma.

BACKGROUND: Bile duct injuries after transarterial chemoembolization (TACE) have been reported; however, the exact pathogenic mechanisms and clinical implications of the injuries remain to be clarified. STUDY: A total of 950 consecutive patients with hepatocellular carcinoma (HCC) were studied. Among them, 807 were treated with TACE and the remaining 143 were treated with transarterial chemoinfusion (TACI) of cisplatin. RESULTS: None of 143 patients with HCC treated with TACI were found to have any radiographic evidence of biliary injury. In contrast, of the 807 patients treated with TACE, 17 (2%) developed biliary complications. Of all complications, 12 (71%) were subcapsular bilomas; 3 (17%), focal strictures of the common hepatic duct or common bile duct; and 2 (12%), diffuse mild dilatation of the intrahepatic bile ducts. Interestingly, 2 of the 12 bilomas were found in the lobe that was not embolized with gelatin sponge particles. The median numbers of TACE tended to be greater in the patients with focal stricture than in those with bilomas (6.0 vs. 2.5; p = 0.08). All 3 patients with focal strictures and 4 of the 12 patients with bilomas had associated serious bacterial infections at presentation. CONCLUSIONS: Bilomas seem to be caused by iodized oil rather than gelatin sponge particles; focal strictures of large bile ducts seem to be caused by gelatin sponge particles. We suggest that adjustments in the amounts of iodized oil or gelatin sponge particles and in the sites of embolization may reduce ischemic biliary injuries after TACE.

Adult↗
PubMedDate not supplied

Close correlation of p53 mutation to microvascular invasion in hepatocellular carcinoma.

Mutation of p53 is a poor prognostic indicator of hepatocellular carcinoma (HCC). Although poor histologic differentiation of HCC has been associated with p53 mutations, the exact reasons for unfavorable clinical outcomes in patients with HCC remain to be clarified. In this study, we evaluate the association between p53 mutation and histopathologic features of HCCs, as well as tumor recurrences and survival. We examined 20 HCCs and surrounding liver tissues from patients who underwent surgical resection, and we performed direct sequencing of p53 gene. p53 mutations were found in 9 of 20 HCCs; none were found in the surrounding liver tissue. p53 mutations were frequent in large, multinodular, and poorly differentiated HCCs. Five of 9 with p53 mutation (in contrast, none of 11 with wild-type mutation) showed microvascular invasions. Hepatocellular carcinoma recurred in 6 of 9 with p53 mutation, in contrast to only 2 of 11 with wild-type mutation. The 1-year survival rate with p53 mutation was significantly lower than that with wild-type. In conclusion, it is suggested that p53 mutations tend to be commonly associated with microvascular invasions, which may result in micrometastasis, followed by frequent recurrences.

Carcinoma, Hepatocellular↗
PubMedDate not supplied

Correlations of serum lipids, uric acid, and albumin among mothers, offspring, and siblings in Taipei, Taiwan.

The purpose of this study was to investigate the correlations of serum lipids, uric acid, and albumin, among mothers (n = 111), offspring (n = 208), and siblings (n = 57) in Taipei, Taiwan. Analytical items included serum triglyceride, serum total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, uric acid, and albumin. Statistical analysis was performed according to the SAS UNIVARIATE procedure; while regression coefficient, parent-offspring regressions, paired-comparison and heritability were estimated. These results show higher heritabilities of four types of serum lipids, uric acid and albumin between mothers and testers (bYX) or siblings (bZX) by parent-offspring regression analysis. Regression coefficients (bYX) of six characters were significantly different (p < 0.05-0.01). Regression coefficients (bZX) for total cholesterol, low-density lipoprotein cholesterol, uric acid, and albumin were significantly different (p < 0.05-0.01), showing the result of genetic control, because their heritabilities were very high at 0.75-1.0, 0.77-1.0, 0.96-1.0, and 0.48-0.82, respectively. This study disclosed that the serum lipids of children in Taipei, Taiwan were significantly correlated with that of parents, which may be attributed to the result of genetic control.

Child↗
PubMedDate not supplied

Factors predictive of survival in patients with node-positive colorectal cancer in Taiwan.

BACKGROUND/AIMS: Preoperative CEA levels, depth of tumor penetration, and the number of positive lymph nodes were reported as independent factors prognostic of survival in colorectal cancer patients. This study was carried out in an effort to evaluate the prognostic significance of these three factors in patients with Dukes' C colorectal cancer in Taiwan. METHODOLOGY: Between 1992 and 1994, a total of 112 patients with node-positive colorectal cancer were evaluated retrospectively at the Veteran General Hospital-Taipei. All patients underwent potentially curative surgery and received 5-fluorouracil based adjuvant chemotherapy. Reference to the Dukes' classification was according to the classical criteria described in 1932 for carcinoma of the rectum and adapted for use in colonic tumors. Data on the location of the tumor, depth of penetration, number of positive lymph nodes, degree of tumor differentiation, and preoperative CEA levels were analyzed to understand their association with survival. Blood samples for CEA measurement were taken a few days before operation. A multivariate analysis using the Cox's proportional hazards regression model was then performed to determine the most important independent predictors of survival among all the possible variables. RESULTS: Using univariate analysis the number of positive lymph nodes (P < 0.001), penetration of the bowel wall (P < 0.001), and preoperative CEA levels (P < 0.001) were found as significant prognostic factors, while the degree of tumor differentiation, location of the tumor, age and sex were not significant. Using multivariate Cox analysis the number of positive lymph nodes, penetration of the bowel wall, and preoperative CEA levels were still found as independent prognostic factors in node-positive colorectal cancer patients. CONCLUSIONS: Data obtained from our study indicates that preoperative CEA levels, depth of tumor penetration, and the number of positive lymph nodes were independent prognostic factors in Dukes' C colorectal cancer patients. They could serve as appropriate modifications of the initial Dukes scheme in node-positive diseases.

Carcinoembryonic Antigen↗
PubMedDate not supplied

Randomized trial comparing weekly bolus 5-fluorouracil plus leucovorin versus monthly 5-day 5-fluorouracil plus leucovorin in metastatic colorectal cancer.

BACKGROUND/AIMS: The purpose of this study was to compare the efficacy and toxicity profiles of weekly intravenous (i.v.) bolus injection of 5-fluorouracil plus low-dose leucovorin with the Mayo Clinics' monthly 5-day schedule of 5-fluorouracil and leucovorin in the treatment of metastatic colorectal cancer. METHODOLOGY: A total of 96 patients with previously untreated metastatic colorectal cancer were randomized to receive either a weekly i.v. bolus injection of 5-fluorouracil 400 mg/m2 plus leucovorin 20 mg/m2 (weekly arm), or i.v. bolus injection of 5-fluorouracil 425 mg/m2 plus leucovorin 20 mg/m2 for 5 consecutive days every 4 or 5 weeks (monthly arm). Therapy was continued until disease progression or unacceptable toxicity appeared. In the presence of disease progression, the study regimen was stopped and second-line treatment was instituted after the patient was discontinued from this study. RESULTS: There was no significant difference of response rates between both regimens. The response rate were 14.3% in the weekly arm (2 CR and 5 PR, 95% CI: 2.6-25.2%) and 10.6% in the monthly arm (1 CR and 4 PR; 95% CI: 6.5-32.3%), respectively (P = 0.8957). The survival times were also similar between the two (P = 0.4207, log-rank test). The median survival were 15.8 months in the monthly arm and 18.4 months in the weekly arm. Hematologic toxicity was minimal in both arms. However, the monthly arm produced a higher toxicity in severe (grade 3-4) diarrhea (14.9% vs. 2%; P = 0.029) and stomatitis (8.5% vs. 0; P = 0.054). CONCLUSIONS: Weekly bolus injection of 5-fluorouracil and low-dose leucovorin achieved a similar response rate and survival as compared with the Mayo Clinics' monthly 5-day schedule, but severe toxicity was less commonly seen using the weekly regimen. As current chemotherapeutic treatment for metastatic colorectal cancer is largely palliative rather than curative, the weekly bolus regimen may be a more favorable approach in managing metastatic colorectal cancer.

Aged↗
PubMedDate not supplied

Influence of muscle activity on the actions of chloride channel blockers in the mouse skeletal muscle.

The purpose of this work was to investigate the effect of channel blockers in the presence and absence of nerve and/or muscle activity. 9-Anthracenecarboxylic acid (0.03 mM), a chloride channel blocker, increased both the amplitude and duration of the contractile response to direct stimulation in the mouse soleus muscle in either low Ca2+ Krebs (0.25 mM) or normal Ca2+ Krebs (2.5 mM) containing 0.1 mM 4-aminopyridine (potassium channel blocker). In addition, spontaneous contractions were induced by 9-anthracenecarboxylic acid in low Ca2+ Krebs. On the other hand, the combination of two potassium channel blockers, 4-aminopyridine (0.3 mM) plus tetraethylammonium ion (10 mM), increased the twitch amplitude but only slightly increased the contractile duration in the mouse soleus muscle in normal Krebs. The contraction-potentiating actions of 9-anthracenecarboxylic acid were inhibited by denervation, while those of 4-aminopyridine plus tetraethylammonium were not. Chronic exposure to the sciatic nerve to a lidocaine-cuff, but not to a colchicine-cuff, exhibited similar effects as denervation. Direct electrical stimulations were applied for 2 days to the soleus muscle through implanted teflon-coated multistranded electrodes in vivo, beginning immediately after denervation or cuff treatments. The contraction-potentiating effects of 4-aminopyridine plus 9-anthracenecarboxylic acid or 9-anthracenecarboxylic acid in low Ca2+ Krebs were restored in the denervated or lidocaine-cuff-treated soleus muscle by chronic direct stimulations. The membrane potential and input resistance of muscle fibres and the effects of 9-anthracenecarboxylic acid, which were altered by denervation or cuff treatment, were also partially restored by this measure. When sciatic nerves had been treated with lidocaine-cuff for 4 days and the cuff was then removed for 7 days, the contraction-potentiating effects of 9-anthracenecarboxylic acid were also restored. Four days after Achilles tenotomy, the contraction-potentiating effects of 9-anthracenecarboxylic acid were markedly inhibited. It was concluded that muscle activity controls the properties of chloride channels and that neural activity may affect the properties of chloride channels via enhancement of the muscle contraction.

4-Aminopyridine↗