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C C Hsieh

Publications and source records attributed to C C Hsieh.

264 records · Page 15Linked to original sources
PubMed1977

Studies on Thermoactinomyces sp. TM9208. I. Description of the strain.

A strain of Thermoactinomyces sp., TM9208, isolated from a soil sample in the Taipei area showed antagonistic activity to Gram positive bacteria but not to the Gram negative on the potato extract agar plate by the cross streaking method. The strain showed strong starch hydrolysis, beta type of hemolysis, brownish yellow growth on the potato extract agar and green on the nutrient agar. Its aerial mycelium, white to grayish white, was long and straight with short branches. The spores are single and have smooth surface. It is a good utilizer of starch, maltose and cellobiose as carbon source, but utilizes dulcitol, salicin, sucrose, rhamnose and sorbitol poorly.

Bacteria↗
PubMedDate not supplied

Olive oil and human cancer: an assessment of the evidence.

BACKGROUND: We have attempted to summarize the evidence concerning the association of olive oil intake with cancer risk in humans. METHODS: We reviewed all the studies that met the following criteria: (1) they have directly examined olive oil in the context of an extensive food frequency questionnaire or have evaluated the role of monounsaturated fat in populations of Mediterranean countries where a large fraction of monounsaturated fat originates from olive oil and (2) they have analyzed the data with explicit or implicit control for energy intake to accommodate the likely confounding influence of caloric consumption and to account to a certain extent for differential completeness of reporting between cases and controls. Ecologic studies were also considered and relevant experimental data were invoked. RESULTS: With respect to breast cancer, there is converging evidence for a protective effect, although the data are not definitive. For other cancer types, the overall epidemiologic evidence, although promising, is quantitatively limited and qualitatively suboptimal. CONCLUSIONS: The issue is of major public health importance and deserves additional study.

Animals↗
PubMedDate not supplied

A cohort study on mortality and exposure to polychlorinated biphenyls.

In 1979, an outbreak of food poisoning ("Yu-Cheng") occurred in Central Taiwan, ROC, involving more than 2000 people. The event was caused by ingestion of rice oil contaminated with polychlorinated derivatives of biphenyls, dibenzofurans, and quaterphenyls. A retrospective cohort study on mortality was undertaken, and possible long-term health effects in the affected individuals were studied. The mortality experience of 1940 victims (929 males, 1011 females) between 1980 and 1991 was compared with the expected numbers, which were calculated from national and local mortality rates. By the end of 1991, 102 deaths were identified, thus producing a standardized mortality ratio (SMR) of overall mortality of 0.99 for males and 1.34 for females. Total cancer mortality was lower than in each comparison group. Mortality from liver diseases was elevated significantly (SMR = 3.22), especially during the first 3 y after the food-poisoning event (SMR = 10.76). Increased clinical severity of polychlorinated biphenyl intoxication was associated with increased mortality from all causes and from liver diseases. In summary, there was a positive association between mortality and intoxication dose, and severe polychlorinated biphenyl poisoning acutely affected mainly the liver. A continued follow-up of this cohort would be valuable in the study of long-term health effects of polychlorinated biphenyl poisoning.

Adolescent↗
PubMedDate not supplied

Successful use of pooled sera to estimate HIV antibody seroprevalence and eliminate all positive cases.

Pooling specimens when testing them in large numbers can save scarce resources and several earlier reports have indicated this to be a feasible strategy. In an HIV antibody mass screening test carried out in our laboratory, we used Dorfman's two-stage model. We sought to establish the optimal number of specimens in a pool, and to achieve maximum efficiency while maintaining both sensitivity and specificity. Before testing for HIV antibody, five positive samples were placed in a set of 1012 sera in a double blind manner, one positive sample into a second set of 1012 sera and none in a third set. The positive rate was assumed to be 0.2% for each set of 1012 sera. As indicated by our model, 22 individual serum samples were placed into each of 46 pools which, when tested by particle agglutination assays, lead to the identification of all positive samples. We concluded that the prevalence rate can be estimated in the first stage, 95% confidence intervals were given, and the efficiency rate could be calculated for the identification of all infected specimens in a large number of samples showing low prevalence rates.

Blood Specimen Collection↗
PubMedDate not supplied

Hepatofugal flow on computed tomography of arterial portography: its correlation with esophageal varices bleeding.

BACKGROUND/AIMS: To study the portal flow patterns from CTAP (computed tomography of arterial portography), then to predict the existence of esophageal varices bleeding clinically. METHODOLOGY: 192 patients who underwent CTAP from superior mesenteric artery infusion were recruited in this study. The obtained images were classified according to our proposed criteria. Stage 0: hepatopetal flow, when all the contrast medium from the superior mesenteric vein entered the portal vein. Stage 1: when the contrast medium opacified the splenic vein or the other collateral vessels. Stage II: when the contrast medium opacified the paraesophageal vessels without entering the inner wall of the esophagus. Stage III: when the contrast medium opacified the collaterals up to the inner wall of the esophagus. RESULTS: The incidence of bleeding esophageal varices was correlated to the different stages of collateral flows pattern obtained. The esophageal varices bleeding rates were 0/137, 1/16, 1/14, 16/25 for stage 0, I, II and III, respectively. The incidence of bleeding esophageal varices was significantly higher in stage III group than in the other groups (P < 0.001). The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of stage III patients in regard to the occurrence of bleeding esophageal varices were estimated as 80.0%, 98.8%, 88.9%, 94.8%, and 94.3%, respectively. CONCLUSIONS: Our results show that CTAP demonstrates the portal flow patterns and collateral veins clearly, which can serve as an excellent imaging modality to predict the risk of esophageal varices bleeding.

Adolescent↗
PubMedDate not supplied

The effect of curing light intensity on the cytotoxicity of a dentin-bonding agent.

Various dentin-bonding agents (DBAs) have been widely used to improve the bonding strength of dental resins and to prevent microleakage at the resin-dentin interface, although DBA may exert potentially detrimental effects upon dental pulp. In this study, a DBA (Scotchbond Multi-purpose) cured at different light intensities (100, 200 and 300-mW/cm2) for 10 seconds was extracted with Dulbecco's modified Eagle's medium (DMEM) for 24 hours. Thereafter, pulp cells (1 x 10(4) cells/well) were exposed to DMEM with or without DBA extract for 12 hours, 24 hours and five days. Pulp-cell cytotoxicity was measured with a modified 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. No significant cytotoxicity of DBA eluents on pulp cells was found for the 12-hour exposure group. Following 24-hour exposure of cells to DBA cured at 100-mW/cm2, pulp cells became rounder, more retracted and lost some cellular processes as compared to controls. Five-day exposure of pulp cells to DBA extract cured by light at levels of 100, 200 and 300 mW/cm2, respectively, led to a growth retardation of 26%, 48% and 70% as analyzed by the inhibition of mitochondrial dehydrogenase activity. These results indicate that DBA may exert some cytotoxic effects upon dental pulp, especially when DBA-curing is insufficiently complete, as may occur at a low light intensity.

Cell Division↗