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Biomedical subjects

W Zheng

Publications and source records attributed to W Zheng.

At least 271 records · Page 15Linked to original sources
PubMed1994

Diagnostic X-ray and ultrasound exposure and risk of childhood cancer.

In a population-based case-control study of 642 childhood cancer cases and the same number of matched controls in Shanghai, China, we evaluated the relationship between diagnostic X-ray (preconception, pre- and post-natal) and antenatal ultrasound exposure and the subsequent risk of developing three major types of childhood cancer (acute leukaemia, lymphoma and brain tumours) and all childhood neoplasms combined. Consistent with previous studies, prenatal X-ray exposure was found to be associated with an 80% increased risk of childhood cancers, although the estimation was based on 4% and 2% exposed cases and controls and was only marginally statistically significant (P = 0.08). Post-natal X-ray exposure was also linked with a small elevation in the risk of all cancers and the major categories of malignancies in children. Little evidence, however, was found to relate parental preconception X-ray exposure with the subsequent cancer risk in offspring, regardless of the exposure window and the anatomical site of X-ray exposures. This study adds further to the growing literature indicating that antenatal ultrasound exposure is probably not associated with an increased risk of childhood cancer.

Adolescent↗
PubMed1994

Tissue distribution and elimination of indium in male Fischer 344 rats following oral and intratracheal administration of indium phosphide.

The use of indium phosphide (InP) in the semiconductor industry has raised concerns about potential occupational exposure. The tissue distribution and elimination of indium were investigated in adult male Fischer 344 rats following either a single or 14 consecutive daily oral doses, or following an intratracheal instillation of InP (10 mg/kg). The concentrations of indium ions in blood, urine, feces, and tissues were quantified either using direct acid digestion followed by electrothermal atomic absorption spectrophotometry (ET-AAS) or using an extraction method with methyltricapryl ammonium ions to remove indium from the matrix followed by ET-AAS. Indium was poorly absorbed from the gastrointestinal tract in both single and multiple oral dose studies. Upon its absorption, indium was relatively evenly distributed among the major organs such as liver, kidney, lung, spleen, and testes. By 96 h after oral dose treatment, less than 0.11% of the dose of indium was recovered from tissues in the single- or multiple-dose experiment. At 96 h, retention of indium in the body was about 0.36% of the dose (except for lung) following intratracheal instillation of InP. Following oral dose administration, the majority of indium was recovered from the gastrointestinal tract and its contents. The high recovery of indium (73% of the dose) in the feces after intratracheal instillation presumably reflects mucociliary clearance and/or biliary excretion of indium. Urinary indium accounted only for 0.08-0.23% of the dose during a 240-h collection period in both single- and multiple-dose studies. It seems that fecal excretion serves as the major route for indium elimination, and this results from poor absorption. Because of the poor absorption of indium following multiple oral doses or intratracheal instillation of InP, it seems unlikely that indium will accumulate in the body following InP exposure.

Administration, Oral↗
PubMed1994

A nested case-control study of oesophageal and stomach cancers in the Linxian nutrition intervention trial.

BACKGROUND: Rates of oesophageal/gastric cardia cancer in Linxian, a rural county in north central China, are among the world's highest, but the risk factors are not well understood. METHODS: A nested case-control study of oesophageal and stomach cancers was conducted within a cohort of 29,584 adults who participated in a randomized nutrition intervention trial. Information on participant characteristics collected during interviews before the trial began was compared between individuals who subsequently developed cancers of the oesophagus (N = 640) or stomach (N = 539), mainly cardia, and individually matched controls (control/case ratio = 5). Analyses were performed separately for oesophageal and stomach cancers using conditional logistic regression. RESULTS: For oesophageal cancer, tobacco smoking was associated with a significantly elevated risk, with a twofold increase among long-term smokers. Alcohol consumption was uncommon and not related to risk. High consumption of eggs or fresh vegetables was associated with 20% reductions in risk, and risk significantly declined as pre-trial body mass index (BMI), an indicator of long-term nutritional status, increased. No increases in risk were associated with intake of pickled vegetables or mouldy foods, although consumption levels at the start of the trial were low. Excess risks of 40-80% were found among individuals who had reported a history of cancer, notably of the oesophagus and stomach, in parents or sibs. For stomach cancer, only low BMI was significantly associated with elevated risk. CONCLUSIONS: This study indicates that several risk factors for oesophageal and stomach cancers in Linxian, including smoking, nutritional deficiency, and familial cancer occurrence, resemble those in other areas of the world and contribute partly to the remarkably elevated rates in this area of China.

Adult↗
PubMed1994

Diet, serum markers and breast cancer mortality in China.

This county-based correlation study examined associations of breast cancer mortality with dietary habits and certain serum biochemical markers, utilizing data collected from an ecological survey in 65 Chinese rural counties. Univariate correlation and multivariate regression analysis showed that consumption of animal foods, including eggs, fish and meat, was positively linked to county-wide mortality rates of breast cancer in Chinese women. No clear associations between breast cancer mortality rates and consumption of green vegetables, carrots and fruits were observed in this study. A modest inverse correlation between serum vitamin C levels and breast cancer mortality was observed, while selenium levels were positively related to the mortality rates. Positive correlations for serum ferritin and hemoglobin were found, in agreement with recent reports of an elevated cancer risk with increased body iron stores. Limitations of these ecological data preclude causal inferences, but the findings provide clues to breast cancer risk and protective factors in a low incidence area of the world.

Adult↗
PubMed1994

[A controlled study of chemiluminescent enzyme immunoassay for the measurement of estrogen receptor in tissue of gynecological neoplasms].

UNLABELLED: In this study, chemiluminescent enzyme immunoassay (CLEIA) has been developed for the measurement of estrogen receptor (ER) in 34 gynecological oncological tissues from 15 cases of endometrial carcinoma, 15 cases of ovarian tumors and 4 cases of other gynecological tumors. The accuracy, specificity and sensitivity of CLEIA for ER were compared with that of dextran-coated charcoal (DCC) and enzyme immunoassay (EIA). RESULTS: (1) the standard curve of ER-CLEIA showed a significant linear correlation between the luminosity and ER concentration (r = 0.9786, P < 0.001); (2) The results of CLEIA and that of the other two methods were compared; the correlation coefficients were > 0.8 and their corresponding rates were > 90%; (3) the positive rate of ER determined by these three methods showed no significant differences, however, the mean value of ER-CLEIA was the highest among them. It is concluded that the CLEIA has a higher sensitivity than that of the other two methods for the measurement of ER.

Adenocarcinoma↗
PubMed1994

[Expression of cDNA RA538 induces terminal differentiation and apoptosis of its parental malignant cell line in vitro].

A full-length cDNA (RA538) was isolated from human esophageal cancer cell line EC8712 after retinoic acid treatment. An expression vector of this cDNA (pRA538) was cotransfected with the neo gene (pDORneo) into parental cancer cell line EC8712. The cell colonies obtained after selection in G418-containing culture medium showed very poor growth, reduced (by 68%-76%) 3H-TdR uptake and morphological changes characteristic of terminal differentiation and programmed cell death (apoptosis). In situ hybridization with RA538 probes revealed expression of mRNA of RA538 in the cytoplasm of the transfected cells. The cells transfected solely with pDORneo after G418 selection showed normal growth pattern and no RA538 expression. However, none of the control cells EC8712 survived the G418 selection. Thus the expression of cDNA RA538 has a similar effect on the esophageal cancer cell EC8712 as the retinoic acid does.

Animals↗
PubMed1993

Risk factors for cancers of the nasal cavity and paranasal sinuses among white men in the United States.

A case-control analysis of cancer of the nasal cavity and sinuses was performed using data from the 1986 National Mortality Followback Survey. Data on cigarette smoking, alcohol consumption, usual diet, and other factors from 147 white men who died from nasal cancer and from 449 controls who died from other causes were compared. Cigarette smoking was related to an increased risk of nasal cancer, with a doubling of risk among heavy or long-term smokers and a reduction in risk among long-term quitters. Among nonsmokers, having a spouse who smoked was associated with a significantly elevated risk of nasal cancer. After adjustment for smoking, a significant dose-response relation was also noted between alcohol drinking and risk of nasal cancer. High consumption of salted/smoked foods was associated with elevated risk, and risk tended to decrease with increasing intake of vegetables. Associations were more pronounced for cigarette smoking and certain dietary items when the analysis was restricted to maxillary sinus cancer. The study confirms that cigarette smoking is a risk factor for nasal cancer, and provides further evidence that dietary factors may play a role in the etiology of this malignancy.

Aged↗
PubMed1993

Occupational physical activity and the incidence of cancer of the breast, corpus uteri, and ovary in Shanghai.

BACKGROUND: A sedentary life style has been consistently associated with an increased risk of colon cancer, but the evidence for its association with breast and other gynecologic cancers is limited. METHODS: Occupational information for 3783 incident patients with cancer (breast, 2736; corpus uteri, 452; and ovary, 595) whose disease was diagnosed during the period 1980-1984 was compared with 1982 census data on employment in Shanghai urban areas. The standardized incidence ratios (SIR) of these cancers were estimated for each occupational group classified by job titles and physical activity levels. RESULTS: A significantly increased incidence of breast cancer was found among professionals (SIR = 158), government officials (SIR = 131), and clerical workers (SIR = 143); the incidence was reduced among service workers (SIR = 87) and craftsmen (SIR = 91). Occupational physical activity, as measured by sitting time and energy expenditure, was inversely related to breast cancer incidence, with SIR of 127-131 for inactive jobs (sedentary or low-energy expenditure) and 79-93 for active jobs (long periods of standing or high energy expenditure). Similar associations, although to a lesser extent, were also seen for cancer of the corpus uteri and ovary. CONCLUSIONS: Women with low physical activity occupations had an increased incidence of cancer of the breast, corpus uteri, and ovary; the incidence was reduced among women with high-activity jobs. These findings were consistent with observations from earlier studies and provided further evidence that physical activity may lower the risk of these female hormone-dependent cancers.

Breast Neoplasms↗
PubMed1993

Cancer incidence trends in urban Shanghai, 1972-1989.

Incidence data pertaining to more than 250,000 cancer cases diagnosed during the years 1972-1989 among residents of urban Shanghai, China, were analyzed to determine the relative importance of the various malignancies and to discover changes over time. In the most recent 3-year period, lung cancer was the most frequent cancer among men (57.0 per 100,000 person-years, age-adjusted world standard), followed by cancers of the stomach (50.1), liver (29.6), esophagus (13.3), colon (11.2) and rectum (9.4). Among women, breast cancer leads (25.1), followed by cancers of the stomach (23.2), lung (18.8), liver (10.9), colon (10.2) and rectum (7.3). The most impressive increases in incidence rates from 1972-74 to 1987-89 were observed for cancers of the gallbladder (119% and 101% among men and women, respectively), colon (85% and 78%), and brain and other nervous system (71% and 60%). In addition, increases of 20-50% occurred for cancers of the pancreas, male lung, female breast, corpus uteri, kidney, and for non-Hodgkin's lymphoma. Rates declined notably for cancers of the esophagus (-54% and -53%), cervix uteri (-86%), and to a lesser extent (10-20%) cancers of the male stomach and liver. These observed trends can be explained only partly by improvements in cancer diagnosis and completeness of the cancer registry, and most likely reflect changes in the prevalence of risk factors in this population.

Age Factors↗
PubMed1993

Serum micronutrients and the subsequent risk of oral and pharyngeal cancer.

To investigate the relationship between serum micronutrients and the subsequent risk of oral and pharyngeal cancer, a nested case-control study was conducted within a cohort of 25,802 adults in Washington County, MD, whose blood samples were collected in 1974 and stored at -70 degrees C for subsequent assays. The serum levels of nutrients in 28 individuals who developed oral and pharyngeal cancer during 1975 to 1990 were compared with levels in 112 matched controls. Serum levels of all individual carotenoids, particularly beta-carotene, were lower among subjects who developed oral and pharyngeal cancer. The risks of this malignancy decreased substantially with increasing serum level of each individual carotenoid. Persons in the highest tertile of total carotenoids had about one-third the cancer risk as those in the lowest tertile. High serum levels of alpha-tocopherol also were related to a low oral cancer risk in later years, but the risks were elevated significantly with increasing serum levels of gamma-tocopherol and selenium. The findings from this study are consistent with many previous epidemiological investigations of dietary factors for oral and pharyngeal cancer and provide further evidence for the potential role of carotenoids and alpha-tocopherol in the chemoprevention of these malignancies.

Carotenoids↗
PubMed1993

A population-based case-control study of dietary factors and endometrial cancer in Shanghai, People's Republic of China.

The relation between diet and endometrial cancer was examined in a population-based case-control study conducted in Shanghai, People's Republic of China, between 1988 and 1990, involving interviews with 268 cases and 268 controls aged 18-74 years. The subjects' usual dietary intake of 63 major foods during the previous 10 years (disregarding any recent changes) was measured by means of a structured quantitative food questionnaire. Although women in the highest quartile of total caloric intake had a 2.1-fold increased risk of endometrial cancer, risk varied according to the source of calories. The highest quartiles of caloric intake from fat and protein were associated with odds ratios of 3.9 and 3.1, respectively, while calories from carbohydrates, the major contributor of total calories in this population, were not related to risk. The association of fat and protein with endometrial cancer risk was confined to foods of animal origin in the diet. After adjustment for age, body mass index (weight (kg)/height (m)2), and number of pregnancies, odds ratios were 3.5 (95% confidence interval (CI) 2.0-6.0) and 3.0 (95% CI 1.7-5.1) for women in the highest quartiles of intake of animal fat and animal protein, respectively. Food group analyses showed a similar pattern, with high consumption of meat, eggs, and fresh fish being associated with elevated risks. After adjustment for total calories, no significant association of risk was found with intake of vegetables or dark green/yellow vegetables, or with estimated carotene intake, although fruit and allium vegetables were associated with some reduction in risk. These results suggest that diets rich in animal fat and animal protein may play an important role in the etiology of endometrial cancer.

Adolescent↗
PubMed1993

Occupational risks for primary liver cancer in Shanghai, China.

Using occupational data for over 3,400 primary liver cancer cases diagnosed between 1980 and 1984 reported to the Shanghai Cancer Registry, and employment information from the 1982 census for the Shanghai population, standardized incidence ratios were computed to generate leads to occupational risks of liver cancer. Among men, a statistically significant excess number of cases was observed for chemical processors, textile workers, wood workers, blacksmiths and machine-tool operators, and material handlers and dock workers. Increased incidence of liver cancer also was observed among female transport equipment operators. These findings indicate that a number of similar occupations are associated with increased risk of primary liver cancer in western countries and China. Although causal inferences cannot be drawn from these data, our study adds to the limited evidence of the potential role of occupational exposures in liver carcinogenesis.

Adult↗
PubMed1993

A cohort study of smoking, alcohol consumption, and dietary factors for pancreatic cancer (United States).

Risk factors for pancreatic cancer were evaluated in a cohort study of 17,633 White men in the United States who responded to a mailed questionnaire in 1966 and were followed-up through 1986 for mortality. Cigarette smoking and alcohol consumption were found to be important risk factors for pancreatic cancer. Risks increased significantly with number of cigarettes smoked, reaching fourfold for smokers of 25 or more cigarettes per day relative to nonsmokers. Alcohol intake also was related significantly to risk, with consumers of 10 or more drinks per month having three times the risk of nondrinkers, but dose-response trends among drinkers were not smooth. Coffee consumption was unrelated to risk. Dietary analyses revealed a rising rate of pancreatic cancer mortality with increasing consumption of meat after adjustment for other risk factors. Men in the highest quartile of meat intake had about three times the risk of those in the lowest quartile. No consistent association, however, was observed for consumption of fruits, vegetables, or grains. This study confirms cigarette smoking as an important risk factor for pancreatic cancer, and provides evidence that elevated intake of alcohol and meat may increase the risk of this fatal malignancy.

Adult↗
PubMed1993

Incidence trends for cancers of the breast, ovary, and corpus uteri in urban Shanghai, 1972-89.

Incidence data from the Shanghai (People's Republic of China) Cancer Registry were used to assess the temporal trends of three major female cancers during 1972-89. Rates for cancers of the breast, corpus uteri and, to a lesser extent, ovary rose over the study period. The increases in breast and ovarian cancer were most pronounced among women under age 50, whereas those for corpus uteri cancer were restricted generally to those aged 55 to 69 years. When considered by cohort year of birth, risk of breast and ovarian cancers rose among women born since 1925 and 1935, respectively, but little evidence of cohort effect was apparent for corpus uteri cancer. Potential explanations for these patterns are explored.

Adult↗
PubMed1993

Prior medical conditions and the risk of adult leukemia in Shanghai, People's Republic of China.

A population-based case-control interview study of 486 adult leukemia cases and 502 healthy controls was carried out in Shanghai, People's Republic of China during 1987-89 to evaluate the etiologic role of prior medical conditions, medications, and diagnostic X-rays. Risks were examined separately for 236 cases with acute non-lymphocytic leukemia (ANLL), 79 with chronic myeloid leukemia (CML), 81 with acute lymphocytic leukemia (ALL), and 21 with chronic lymphocytic leukemia (CLL). Little difference was found between cases and controls for prior history of diabetes, hypertension, allergic conditions, most medications, and diagnostic X-rays. A few significant associations were observed for appendectomy, tuberculosis, and for several other chronic disorders with specific leukemia cell types, but the odds ratio estimates for most of these ranged from two to three and, with the exception of the two specified above, were based generally on five or fewer exposed controls. In contrast to an association with childhood leukemia in Shanghai, prior use of chloramphenicol was not linked with ANLL or other forms of adult leukemia. Further research is needed to clarify the relation of specific medical conditions and exposures with particular subtypes of leukemia, and to examine reasons for the low incidence of CLL in China and other Asian populations.

Adolescent↗
PubMed1993

Declining incidence is greater for esophageal than gastric cancer in Shanghai, People's Republic of China.

Temporal trends in the incidence of esophageal and gastric cancers during 1972 to 1989 were addressed in urban Shanghai, the location of China's longest standing cancer registry. Over the 18 year study period, esophageal cancer rates decreased more than 50% from 28.8/100,000 person-years in 1972-74 to 13.3/100,000 in 1987-89 among men and from 11.3/100,000 to 5.4/100,000 among women. Reductions were apparent in each age group, but most pronounced among younger generations, with more than a 75% decline in incidence among those under age 55 years. The incidence rate for stomach cancer among men decreased 20% from 62.0/100,000 in 1972-74 to 50.1/100,000 in 1987-89. The reduction among women, however, was minor, from 23.9/100,000 to 23.2/100,000. The patterns varied by age, with declines among persons 45-64 years and increases among those in older and younger age groups. The determinants of these trends are not clear, but appear related in part to dietary changes.

Adult↗