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Biomedical subjects

C C Hsieh

Publications and source records attributed to C C Hsieh.

At least 127 records · Page 7Linked to original sources
PubMed1996

Dietary factors and the risk of endometrial cancer: a case--control study in Greece.

In a hospital-based case-control study of endometrial cancer undertaken in Athens (1992-94), 145 women residents of Greater Athens with confirmed cancer of the endometrium were compared with 298 control patients with orthopaedic diseases. Personal interviews were conducted in the hospital setting, and diet was assessed using a validated semiquantitative food frequency questionnaire. Nutrient intakes for individuals were calculated by multiplying the nutrient intake of a typical portion size for each specified food item by the frequency at which the food was consumed per month and summing these estimates for all food items. Data were modelled through logistic regression, controlling for demographic, reproductive and somatometric risk factors for endometrial cancer as well as for total energy intake. No macronutrient was significantly associated with endometrial cancer risk, but increasing intake of monounsaturated fat, mostly olive oil, by about one standard deviation was associated with a 26% risk reduction (odds ratio = 0.74; 95% confidence interval 0.54-1.3). Among micronutrients, only calcium intake was significantly inversely associated with endometrial cancer risk, whereas there was evidence against retinol and zinc imparting protection against the disease. With respect to food groups, there was weak and non-significant evidence that vegetables are protective, whereas consumption of pulses was positively associated with disease possibly because they contribute substantially in Greece to energy intake in excess of physical activity-dependent requirements.

Case-Control Studies↗
PubMed1996

Inhibition of the migration, attachment, spreading, growth and collagen synthesis of human gingival fibroblasts by arecoline, a major areca alkaloid, in vitro.

Because betel quid (BQ) chewing has been linked to a higher prevalence of periodontal diseases, the pathobiological effects of arecoline, a main alkaloid found in areca nut, were investigated in cultured human gingival fibroblasts. At concentrations higher than 0.4 mM, arecoline inhibits cell attachment, cell spreading and cell migration in a dose-dependent manner. These inhibitory effects were associated with intracellular depletion of glutathione (GSH). At concentrations of 0.4 mM and 1 mM, arecoline depleted about 26% and 45% of GSH after 2 h incubation. Exposure of cells to arecoline at concentrations lower than 0.4 mM for 2 h showed no significant decrease in either cell viability or intracellular GSH. However, incubation of cells for 24 h in 1 mM are colined decreased the cell numbers to only 35% of those in the untreated control. Arecoline also decreased cell growth and collagen synthesis in a dose-dependent manner. Because of repeated and long-term exposure to arecoline, BQ chewers could be more susceptible to periodontal damage and less responsive to new attachment procedures.

Arecoline↗
PubMed1996

A case-control study of oral cancer in Changhua County, Taiwan.

Forty oral cancer patients identified consecutively in Changhua Christian Hospital between 1990 and 1992 were compared with 160 population-based controls, matched for sex, age, area of residence, and educational background. Betel quid chewing was positively associated with the risk of oral cancer with adjusted odds ratio of 58.4 (95% CI: 7.6-447.6). The greater the number of years of chewing betel quid, the higher the risk of oral cancer; the adjusted odds rations were 12.9, 93.7 and 397.5 for < 21, 21-40, and > 40 years of betel chewing as compared with the non-users. The risk also increased with the quantity chewed per day; the odds ratios for those chewing < 10, 10-20 and > 20 quids/day were 26.4, 51.2 and 275.6, respectively. These odds ratio estimates were all statistically significantly different from the null value of unity.

Age Factors↗
PubMed1996

Evidence for posttranscriptional regulation of C/EBPalpha and C/EBPbeta isoform expression during the lipopolysaccharide-mediated acute-phase response.

The mRNAs of the CCAAT/enhancer-binding trans-activator proteins (C/EBPalpha and C/EBPbeta) serve as templates for the differential translation of several isoforms which have specific transcriptional regulatory functions. By using an oligonucleotide corresponding to the C/EBP binding site of the mouse alpha1-acid glycoprotein promoter, we detected multiple forms of C/EBPalpha and C/EBP++ beta proteins in the mouse liver that have DNA-binding activity. By using specific antisera, we detected C/EBPalphas with molecular masses of 42, 38, 30, and 20 kDa that have DNA-binding activity. The pool levels of the 42- and 30-kDa isoforms were high in control nuclear extracts and decreased significantly after lipopolysaccharide (LPS) treatment. The binding activity and protein levels of the 20-kDa isoform are low in controls and increase dramatically after LPS treatment. C/EBPbeta isoforms with molecular masses of 35, 20, and 16 kDa were also detected. The 35-kDa pool level did not change whereas the 20-kDa isoform was strongly induced in response to LPS. Western (immunoblot) and Southwestern (DNA-protein) analyses show that p42 C/EBPalpha forms specific complexes with the alpha1-acid glycoprotein oligonucleotide in control nuclear extract and that p20 C/EBP beta forms complexes in LPS-treated liver. Our studies suggest that synthesis of specific C/EBPalpha and C/EBPbeta isoforms occurred in the normal liver in vivo and that LPS mediated a differential initiation and inhibition of translation at specific AUG sites within each mRNA. The qualitative and quantitative changes in C/EBPalpha and C/EBPbeta isoform pool levels suggest that LPS or an LPS-stimulated factor can regulate the selection of AUG start sites for both activation and repression of translation. This regulation appears to involve an LPS-mediated down-regulation of initiation at the first AUG codon of the 42-kDa C/EBPalpha and dramatic translational up-regulation at the fifth AUG codon of the 20-kDa C/EBPalpha and the third AUG codon of the 20-kDa C/EBPbeta. These regulatory events suggest the existence of proteins that may act as translational trans-acting factors.

Amino Acid Sequence↗
PubMed1996

Prenatal diagnosis of major congenital cardiovascular malformations.

This prospective study was designed to determine whether there would be a higher incidence of congenital cardiovascular malformation (CCVM) in pregnant women with certain risk factors. Fetal echocardiography, from second trimester of term, was performed in 1,659 pregnant women with risk factors for CCVMs and 826 pregnant women without risk factors from March 1990 to April 1995. Two-dimensional imaging, fetal M mode measurements, Doppler waveform velocity and Doppler color flow mapping were used for fetal heart examination. During this period, 70 fetuses with major cardiovascular malformations were found. The prenatal detection rate was determined as 2.8% (70/2,485) in our study. The rate in the high-risk group, however, was 3.7% (61/1,659). Of all indications, fetal risk factors had the highest rate (9.3%, 46/494) of detected CCVMs. Maternal and familial indications could be excluded from the high-risk group as they did not show any increased incidence over the low-risk group. We suggest that fetal echocardiography is mandatory in the high-risk group, especially in cases with fetal and placental risk factors. Fetal cardiac screening in the hands of first-line sonographers has a major role in prenatal diagnosis of CCVMs in the low-risk group.

Echocardiography↗
PubMed1996

[A randomized clinical trial for the evaluation of head and neck squamous cell carcinoma treating with traditional Chinese medicine]

This paper described the research design,research process and statistical analysis of randomized clinical trial by treatment with traditional Chinese medicine in patients with squamous cell carcinoma of the head and neck.At first we found there was no significant difference between treating group and contral group(P>0.05) using log-rank test on Kaplan-Meier survival curves. With further multivariate analysis Cox model and after adjusting for sex,age,legth of taking the assigned medication,grade of tumor differentiation and using of chemotherapy,the rate of tumor-related death for control group was significantly higher than that for treating group :hazards ratio estimate was 1.939(95% confidence interval 1.008-3.729,(P<0.05).The length of taking Chinese medicine was one of the most important prognostic factors(P<0.001).The results suggest that the prescribed medication contributed to the improved survival,and it was an independent prognostic factor.

Journal Article↗
PubMed1996

Hyperglycemia induced activation of type-1 protein phosphatase activator (kinase FA) in perfused human placenta.

We report the identification of type-1 protein phosphatase activating factor (kinase FA), a unique biologic mediator for both insulin and epidermal growth factors in the human placenta. The activity of kinase F, was found to be extremely labile in the unperfused placenta. Fresh term placentas lost more than 50% of the total kinase FA activity within 6 hours when exposed to air of incubated in medium but not perfused. In contrast, the activity of kinase FA was stable when the human term placenta was dually perfused. This indicates that placental dual perfusion is a useful method for studying protein phosphorylation-dephosphorylation involved in signal transduction. When fresh placentas were perfused with media containing glucose at 141 +/- 10, 242 +/- 12 and 436 +/- 20 mg/dL, kinase FA activity was stimulated several-fold in a glucose concentration-dependent manner when compared with control levels at delivery. The results suggest that hyperglycemia-mediated activation may represent a previously unknown control mechanisms for the regulation of protein kinase FA. The results also suggest that human placental perfusion is a good in vitro system for studying signal transduction mechanisms involved in hormonal actions and metabolic regulation.

Analysis of Variance↗
PubMed1996

Breast size and mammographic pattern in relation to breast cancer risk.

The relation of Wolfe's parenchymal patterns and radiographically-assessed breast size with breast cancer risk was evaluated in a population-based nested case-control study in Uppsala, Sweden. All women who attended a mammographic screening programme in Uppsala county starting in 1988 have been followed for the occurrence of breast cancer through 1993. The analysis was based on 295 cases and 589 age-matched controls, whose mammograms were blindly evaluated for parenchymal pattern and breast size. Women with P2 or DY pattern had a significantly elevated risk of breast cancer compared with women with N1 or P1 (OR = 2.09; 95% CI = 1.52-2.86). There was an inverse association of breast size with breast cancer risk, which disappeared after adjusting for parenchymal pattern, because breasts of smaller size tended to have high-risk parenchymal patterns. It is concluded that in Swedish women, and perhaps in Caucasian women in general, small breast size is associated with increasing breast risk through its association with high-risk parenchymal pattern. This is in contrast to the fact that Asian women, who in general have breasts of smaller size, have low prevalence of high-risk parenchymal pattern as well as low rates of breast cancer.

Adult↗
PubMed1996

Comparison of calcium phosphate cement mixture and pure calcium hydroxide as direct pulp-capping agents.

Calcium phosphate cement (CPC) and pure calcium hydroxide were used as direct pulp-capping agents on the deliberately exposed pulp tissue of 60 teeth in five monkeys. Their effects on the pulp tissue of individual teeth were observed and histologically compared after 12, 20 and 24 weeks. The results showed that both materials produced similar responses with regard to their biocompatibility and induction of hard tissue barrier formation. Vasodilatation, chronic inflammation and calcification nidi scattered within the pulp tissue of the 12-week group were observed. Twenty weeks after application of capping materials, a crude reparative dentinal bridge with inclusion of soft tissue or bulky capping agents appeared. A more mature, hard tissue barrier with a better degree of mineralization and formation of dentinal tubules was demonstrated in the 24-week group. The above findings associated with the abilities of self-setting and fair compressive strength suggest that CPC appears superior to pure calcium hydroxide and may have potential for clinical application, although many issues remain to be further investigated.

Animals↗
PubMed1996

Erythrocyte Li-Na countertransport in uremic patients: effect of urea.

Abnormalities of erythrocyte cation transport systems including Li-Na countertransport have been described in uremic patients. Dialysis appears to eliminate the difference in some of the patients. We investigated the rate of Li-Na countertransport from erythrocytes of normal healthy subjects and uremic patients undergoing hemodialysis treatment. We found that erythrocytes from uremic patients exhibited a significantly elevated rate of Li-Na countertransport. Furthermore, urea (30 mM) did not affect the rate of Li-Na countertransport or the electrolyte contents for Li loaded erythrocytes. Our findings showed that while both plasma and urea concentration and erythrocyte Li-Na countertransport were elevated in uremic patients, urea was not the major cause of the enhanced activity of the transporter.

Adult↗
PubMed1995

Exercise intensity and longevity in men. The Harvard Alumni Health Study.

OBJECTIVE: To examine the independent associations of vigorous (> or = 6 resting metabolic rate [MET] score) and nonvigorous (< 6 MET score) physical activity with longevity. DESIGN: Prospective cohort study, following up men from 1962 or 1966 through 1988. SETTING/PARTICIPANTS: Subjects were Harvard University alumni, without self-reported, physician-diagnosed cardiovascular disease, cancer, or chronic obstructive pulmonary disease (n = 17,321). Men with a mean age of 46 years reported their physical activities on questionnaires at baseline. MAIN OUTCOME MEASURE: All-cause mortality (3728 deaths). RESULTS: Total energy expenditure and energy expenditure from vigorous activities, but not energy expenditure from nonvigorous activities, related inversely to mortality. After adjustment for potential confounders, the relative risks of dying associated with increasing quintiles of total energy expenditure were 1.00 (referent), 0.94, 0.95, 0.91 and 0.91, respectively (P [trend] < .05). The relative risks of dying associated with less than 630, 630 to less than 1680, 1680 to less than 3150, 3150 to less than 6300, and 6300 or more kJ/wk expended on vigorous activities were 1.00 (referent), 0.88, 0.92, 0.87, and 0.87, respectively (P [trend] = .007). Corresponding relative risks for energy expended on nonvigorous activities were 1.00 (referent), 0.89, 1.00, 0.98, and 0.92, respectively (P [trend] = .36). Analyses of vigorous and nonvigorous activities were mutually adjusted. Among men who reported only vigorous activities (259 deaths), we observed decreasing age-standardized mortality rates with increasing activity (P = .05); among men who reported only nonvigorous activities (380 deaths), no trend was apparent (P = .99). CONCLUSIONS: These data demonstrate a graded inverse relationship between total physical activity and mortality. Furthermore, vigorous activities but not nonvigorous activities were associated with longevity. These findings pertain only to all-cause mortality; nonvigorous exercise has been shown to benefit other aspects of health.

Adult↗
PubMed1995

Perinatal characteristics and adult mammographic patterns.

We retrieved breast mammograms for 370 women 40 to 74 years old with no history of breast cancer, for whom birth weight, birth length, placental weight and other birth characteristics were indicated in their standard birth records at the Uppsala University Hospital. Blind evaluation of the mammograms allowed these to be classified according to Wolfe's pattern. Logistic regression analysis was applied using as independent variables the recorded birth characteristics and as outcome variable, high risk (P2 and DY) versus low risk (N1 and P1) mammographic parenchymal pattern. After controlling for all the recorded variables, the odds ratio for a high-risk pattern (P2 or DY) increased consistently and significantly (P for trend 0.02) with the weight of the placenta, i.e. the main estrogen-producing organ during pregnancy. There were weak and non-significant positive associations with increasing birth weight (P for trend 0.53) and birth length (P for trend 0.52). These results are compatible with hypotheses suggesting that pregnancy estrogens or other perinatal characteristics may play a risk-modulating role influencing breast cancer in the offspring.

Adult↗
PubMed1995

Abortion and breast cancer risk in seven countries.

Epidemiologic studies have been inconsistent in suggesting an association between abortion and breast cancer risk. Whether the protection provided by a full-term pregnancy also results from a short-term pregnancy or whether a prematurely terminated pregnancy could increase the risk of breast cancer is unclear. Data from a large, international collaborative study were used to evaluate the association between abortions, whether spontaneous or induced, and breast cancer risk. The data from seven countries included 3,958 breast cancer cases and 11,538 hospital controls with information on abortion history obtained through interviews. Compared with nulliparous women with no abortion (baseline), the odds ratios (OR) and 95 percent confidence intervals (CI) were: for nulliparous women with a history of prior abortion, 0.86 (CI = 0.68-1.08); for parous women with no history of abortion, 0.63 (CI = 0.57-0.69); for parous women with abortion before first birth, 0.82 (CI = 0.69-0.97); and, for parous women with abortion only after first birth, 0.70 (CI = 0.63-0.79). When restricting analysis to parous women, those with a history of abortion exhibited an elevated OR suggesting a 29 percent risk increase if the incomplete pregnancy occurred before first birth (CI = 1.16-1.36) and an 11 percent risk increase for abortion only after first birth (CI = 1.02-1.20) compared with women without such history. The associations observed were stronger among the youngest women. These results do not support a large overall association between abortion and breast cancer risk.

Abortion, Induced↗
PubMed1995

Green-tea consumption and risk of stomach cancer: a population-based case-control study in Shanghai, China.

The effect of drinking Chinese green tea on the risk of stomach cancer was evaluated in a population-based case-control study conducted in Shanghai, China, from October 1991 to December 1993. Eligible cases were incident cases of primary stomach cancer diagnosed during the study period among residents of Hongkou district and Nanhui county aged under 80 years. Controls were selected from the same street or commune where the case resided and were matched to the cases on age (within three years) and gender. A total of 711 cases and 711 matched controls, more than 90 percent of the eligible subjects, completed the interview. Information was obtained on the types of tea used, age when habitual tea drinking started, frequency of new batches of tea leaves used per day, number of cups brewed from each batch, total duration of drinking for each batch, strength and temperature of the tea consumed. Statistical analysis was based on modelling through conditional logistic regression. After adjusting for age, gender, place of residence, education, birthplace, alcohol consumption, and cigarette smoking, the odds ratio (OR) comparing drinkers of green tea with nondrinkers was 0.71 (95 percent confidence interval = 0.54-0.93). The adjusted OR decreased with increasing number of new batches of the green tea consumed each day (P value trend = 0.006). With the largest series of stomach cancer cases to date, this study found green-tea consumption associated with lower risk of stomach cancer. Among drinkers of green tea, the risk of stomach cancer did not depend on the age when habitual green-tea drinking started. Green tea may disrupt gastric carcinogenesis at both the intermediate and the late stages.

Adult↗
PubMed1995

Organochlorine compounds and estrogen-related cancers in women.

The organochlorines, a diverse group of some 15,000 compounds, have been implicated increasingly as being harmful to humans. Some congeners of DDT and PCB elicit very weak estrogenic responses in animals, while the dioxin TCDD and related compounds have antiestrogenic properties. This review summarizes the evidence regarding whether certain organochlorine compounds, usually as persistent food-chain contaminants, increase the risk of breast and endometrial cancers through their estrogenic potential. In humans, neither ecologic data nor occupational studies provide clear support for an association between organochlorine exposure and the occurrence of these cancers. In our summary analysis of occupational exposure, the rate ratio of breast cancer for exposed cf unexposed women was 0.84 (95 percent confidence interval [CI] = 0.50-1.33) for PCBs and 1.08 (CI = 0.68-1.58) for TCDD. Similarly, effect estimates close to unity were found in summary analysis of breast cancer case-control studies regarding levels of DDE and PCB in adipose tissue or serum. In two recent nested case-control studies using stored specimens, the odds ratio per standard deviation increase in serum p,p'-DDE was 1.27 (CI = 0.95-1.69). Although estrogenic effects of certain organochlorine compounds should be easier to detect on the endometrium, we know of no analytic epidemiologic studies of endometrial cancer published to data. We conclude that available data do not indicate that organochlorines will affect the risk of these two cancers in any but the most unusual situation.

Adipose Tissue↗