Biomedical subjects

Taiyi Jin

Publications and source records attributed to Taiyi Jin.

29 records · Page 2Linked to original sources

PubMed2004

Informed consent in China: quality of information provided to participants in a research project.

AIMS: A study was carried out of informed consent strategies in an epidemiological project approved by the regional research ethics committees in Sweden and China and conducted in three areas south-west of Shanghai. METHODS: All participants in the epidemiological project (EP) were included in the research ethical study (RES), which was conducted as a questionnaire-based interview survey in the three areas. Answers were collected by five field interviewers. RESULTS: All participants included answered the questionnaire. Almost all perceived the information provided as rather good or quite good. However, a majority (on average 76%) had the impression that the EP was part of routine healthcare measures, and not a research project. Almost all participants felt free to abstain from participation although 38% in area II stated that they had not been informed about freedom to abstain from participation. A large proportion of participants did not fully understand the nature of the EP. However, almost all participants stated that they would agree to participate in a similar study in the future. CONCLUSION: Although informed consent procedures are supposed to be internationally applicable our study illustrates that it is not always easy to convey information and obtain consent in the present study setting.

Adult↗

PubMed2003

Changes of serum sex hormone levels and MT mRNA expression in rats orally exposed to cadmium.

It has been demonstrated that cadmium (Cd) is carcinogenic to rodent prostate. However, the mechanism of its toxicity is far from fully understood. In the present study, the effects of oral Cd exposure (0, 50, 100, 200 ppm in drinking water) on serum sex hormone levels, the expression of MT-I and MT-II mRNA, and the zinc content of rat prostate were assessed. With Cd administration, serum testosterone (T) levels significantly increased in all Cd groups after 3 months and in the 200 ppm Cd group after 6 months. A significant depression in the serum luteinizing hormone (LH) level was seen in the Cd group (200 ppm) after 6 months. It was noted that Cd administration resulted in a significant down-regulation in the expression of MT-I and MT-II mRNA in the rat ventral prostate. However, no Cd-induced changes in the mRNA expression of Metallothioneins (MTs) were detected in the dorsolateral prostate. After Cd administration, the content of Cd in both the ventral and dorsolateral lobes of the prostate significantly increased with increasing dose and duration of Cd administration. In contrast, the Zn content decreased with Cd administration in both the ventral and dorsolateral lobes of the rat prostate. Taken together, these results suggest that oral Cd exposure may disrupt endocrine homeostasis, changing the distribution of Zn and the mRNA expression of MTs in rat prostate, and that such Cd-induced changes may contribute to the susceptibility of prostate to the carcinogenicity of this heavy metal.

Animals↗

PubMed2003

Influence of environmental cadmium exposure on forearm bone density.

Cadmium may have both direct and indirect effects on bone turnover. It is nephrotoxic and can interfere with vitamin D metabolism. Such perturbation may result in osteoporosis and osteomalacia. In this study, a total of 790 persons (302 males and 488 females) participated; they were all over 35 years old and resided in an area near a cadmium smelter in southeast China. All participants completed a questionnaire, and bone mineral density was measured by SPA-4 single-photon absorptiometry at the radius and ulna. Cadmium content of urine was determined by graphite-furnace atomic absorption spectrophotometry as a measure of dose. The decline in bone mineral density with age in a heavily polluted area was greater than that in a control area for subjects over 60 years of age of both sexes (p < 0.05). In single regression, forearm bone densities were negatively correlated with urinary cadmium excretion in both males and females (p < 0.001), whereas stepwise regression showed that forearm bone density decreased linearly with age (p < 0.001) and urinary cadmium (p < 0.01) in both sexes, suggesting a dose-effect relationship between cadmium dose and bone mineral density. Based on the World Health Organization criteria, (bone mineral density < -2.5 SDs below the normal young adult), the prevalence of osteoporosis in women increased from 34.0% in the control area to 51.9% in the heavily polluted area (p < 0.01) among subjects over 50 years old, and the odds ratio value was 2.09 (95% CI: 1.08-4.03) for the highly polluted area compared with the control area. A striking observation in the study was the marked increase of the prevalence of fracture in the cadmium-polluted area in both sexes. It was concluded that environmental exposure to cadmium is associated with an increased loss of bone mineral density in both males and females, leading to osteoporosis and increased risk of fractures, especially in the elderly and in females.

Adult↗

PubMed2002

Urinary protein excretion in humans exposed to arsenic and cadmium.

OBJECTIVE: In mice, the renal toxicity of arsenic (As) and cadmium (Cd) has been shown to be exacerbated by the simultaneous administration of both elements. To verify the existence of such an interaction in humans, cohorts slightly (Belgian) and moderately (Chinese) exposed to both elements were examined. METHODS: Biological indicators of exposure (Cd in urine and in blood; As in urine) and renal effect parameters (retinol binding protein (RBP); beta(2)-microglobulin (beta(2)M); albumin (ALB); N-acetyl-beta-glucosaminidase (NAG) in urine) were determined and their relationships studied by multiple regression analyses. RESULTS: Changes in renal effect parameters could be ascribed to Cd body burden. RBP and beta(2)M urinary concentration were influenced by exposure to As only in Chinese women, directly and in interaction with Cd exposure. CONCLUSION: A synergistic action of As on the tubular effects of Cd is observed in women moderately exposed to these elements and leads to RBP urinary excretion slightly above normal values.

Acetylglucosaminidase↗

PubMed2002

Cadmium biomonitoring and renal dysfunction among a population environmentally exposed to cadmium from smelting in China (ChinaCad).

Cadmium, an environmental pollutant, can have adverse effects on the human body. The kidney is the critical organ. In order to improve the understanding of the dose-response relationship between cadmium exposure and health effects, and especially renal dysfunction, a study on a general population group in China was performed. This study was therefore concerned with cadmium exposure biomarkers, such as the concentrations in blood (BCd) and urine (UCd), and effect biomarkers of renal dysfunction, such as beta2-microglobulin (beta2m), retinol binding protein (RBP) and albumin (ALB). To improve the evaluation of exposure levels in relation to the adverse health effects of cadmium exposure in the general population, a quality control program was conducted to determine analytical quality in the determination of cadmium in blood and urine and for beta2m, creatinine, ALB and RBP. The measurements showed that analytical quality was adequate. The exposure and effect biomarkers were studied in the population groups living in three areas, namely a control area and two Cd polluted areas. In the highly exposed area, most of the BCd values were higher than 5 microg/l and most of the UCd values were higher than 5 microg/g creatinine. Beta2-microglobulin, retinol binding protein, and albumin in urine were all significantly higher in the population living in the heavily polluted area than in that in the control area. Based on data from all three areas, a marked dose-response relationship between UCd or BCd and the prevalence of renal dysfunction was demonstrated. The number of abnormalities in kidney was related to the level of cadmium exposure. Only one index of renal tubular dysfunction was affected in subjects exposed to low levels of cadmium, but more than two indices of renal function were affected in those exposed to high levels.

Air Pollutants↗

PubMed2002

Adverse effects of gasoline on the skin of exposed workers.

Gasoline is widely used as a solvent in industry. To study its adverse effects on the skin and to understand their mechanisms, a matched epidemiological study (1:1, 52 exposed workers and 52 control subjects) was developed. Information about general conditions, history of dermatosis, changes in skin after exposure to gasoline, etc., was obtained. Ceramide, fatty acid and cholesterol collected from the backs of the hands were analyzed by high-performance thin-layer chromatography (HPTLC), because stratum corneum lipids play a predominant rôle in maintaining the physiological function of skin. The results showed that prevalences of hyperkeratosis, dryness, onychosis and dermatitis were clearly higher in exposed workers than in the control group, prevalence ratios being 3.33 (p<0.05), 3.00 (p<0.001), 11.25 (p<0.001), 5.00 (p<0.001), respectively. Fissures and onychorrhexis were the common symptoms in exposed workers. The stratum corneum lipid levels of ceramide, fatty acid and cholesterol were significantly lower in the exposed group than in the control group (p<0.05). Findings indicated that prolonged or repeated contact with gasoline could cause fissuring of the skin and nail disorders, and that the mechanism was perhaps depletion of stratum corneum lipids.

Adult↗

PubMed2002

Low bone density and renal dysfunction following environmental cadmium exposure in China.

This paper presents the main findings of a study on health effects of environmental cadmium pollution in China, performed in 1998, i.e. approximately 25 years after the first warnings of such effects were published in Ambio. Forearm bone mineral density (BMD) and renal dysfunction were assessed in population groups exposed to cadmium via rice. Decreased BMD was found in postmenopausal women with elevated urinary cadmium (CdU) or cadmium in blood (CdB) and among men with elevated CdB. Also, clear and statistically significant dose-effect and dose-response relationships were found between CdB or CdU and renal dysfunction (increased excretion of retinol-binding protein). This is the first report of bone effects among Cd-exposed population groups in Asia outside Japan. The report is also of interest since it demonstrates that bone effects, a comparatively severe adverse health effect of Cd, in combination with renal dysfunction, still occurs in environmentally exposed population groups in Asia. Recent reports on bone effects in Cd-exposed population groups in Europe are discussed.

Adult↗

PubMed2002

[Changes of serum sex hormone levels in male workers exposed to cadmium].

OBJECTIVE: To investigate the changes in serum levels of sex hormones in male workers occupationally exposed to cadmium (Cd). METHODS: Eighty-five Cd-exposed workers in a cadmium refinery in the south China and 76 local healthy subjects as control were selected in the study. Air samples in the workplaces were collected and detected for Cd concentration. Urinary Cd (UCd) level of the workers was measured by graphite atomic absorption spectrometry (AAS) and adjusted by urine level of creatinine (Cr), as an indicator of Cd-burden in the body of all subjects. Also, their serum levels of testosterone (T), follicle stimulating hormone (FSH) and luteinizing hormone (LH) were determined with radioimmunoassay and enzyme immunoassay, respectively, and dose-effect relationship was evaluated. RESULTS: The serum testosterone levels in Cd-exposure group with 10.9-21.9 and > 21.9 micro mol/mol Cr were 13.00 and 11.37 nmol/L, significantly higher than that (9.31 nmol/L) in those with 0.0-2.2 micro mol/mol Cr. Significantly more increased level of LH (4.11 and 4.32 U/L) was detected in heavy exposure group in the workshop for electrolysis than in control group (2.52 U/L) and in the group with 0.0-2.2 micro mol/mol Cr of UCd (2.64 U/L). No changes in serum level of FSH were found related to Cd exposure. CONCLUSION: Occupational Cd exposure could independently contribute to the changes of serum levels of sex hormone in male workers.

Cadmium↗

PubMed2002

[Effects of gasoline on syntheses of DNA, protein and sebum in keratinocyte and fibroblast].

OBJECTIVE: To study the cellular and molecular mechanism of gasoline-induced adverse effects on skin, particularly on keratinocyte and fibroblast in vitro. METHODS: The primary cell culture of keratinocyte and fibroblast were treated with 0, 0.001%, 0.01%, 0.1% and 1.0% gasoline, respectively. (3)H-thymidine ((3)H-TdR), (3)H-leucine ((3)H-Leu), (3)H-proline ((3)H-Pro) and (14)C-linoleic acid incorporation tests were applied to elucidate their capacity of synthesizing DNA, protein and sebum. RESULTS: The incorporation of (3)H-TdR in keratinocyte and (3)H-TdR and (3)H-Pro in fibroblast inhibited significantly after exposure to 0.01% gasoline (P < 0.05), with inhibition rates 68.5%, 45.1% and 40.6% for (3)H-TdR in keratinocyte, and (3)H-TdR and (3)H-Pro in fibroblast, respectively. Significant depression in incorporation of (3)H-Leu and (14)C-linoleic acid in keratinocyte were found even in the group treated with 0.001% gasoline (P < 0.05), with inhibition rates of 20.2% and 41.2%, respectively. CONCLUSIONS: Solvent gasoline has certain toxic effect on keratinocyte and fibroblast, intervening their normal metabolic and physiological process and affecting their ability of synthesizing DNA, protein and sebum, and their physiological functions, which could be one of the mechanisms causing skin damage by gasoline. The results also indicated that keratinocyte was more susceptible to gasoline than fibroblast.

Animals↗

PubMed2002

[The acute effects of dimethoate on the muscarinic-receptors of rat brains and the relationship between muscarinic-receptors and cholinesterase].

OBJECTIVE: To study the acute effects of dimethoate on the muscarinic-receptors(M1, M2) in the brain of rats. METHODS: 24 Sprague-Dawley rats were divided into 4 groups randomly. They were administered subcutaneously with 0, 25, 50, 100 mg/kg dimethoate, respectively. Brains were removed after 48 hours of administration. Radioligand binding assay was used to determine the density and affinity of M1 and M2 receptors. RESULTS: Rats in the treated group showed low density of M1 and M2 receptors compared with the control rats. The brain M1 receptor density of the rats in the highest dosage group was significantly lower than that in the control group while brain M2 receptors density had a decrease trend with increasing dosage, but the difference showed no significance. However, there were no differences of the affinity of both M1 and M2 among different treated groups. Correlation analysis showed there is positive relationship between cholinesterase activity and density of M1 receptors(r = 0.583, P < 0.01). CONCLUSION: M1 and M2 receptors density decreased with the increasing dosage of dimethoate. It is suggested that the alleviating of cholinergic symptoms may be due to the decrease of M1 and M2 receptors in rat brain.

Animals↗

PubMed2002

[Effects of oral cadmium exposure on expression of metallothionein-I and metallothionein-II mRNA in rat prostate].

OBJECTIVE: To investigate the possible effects of oral cadmium(Cd) exposure on the expression levels of metallothionein-I and metallothionein-II (MT-I and MT-II) mRNA and the distribution of zinc (Zn) and Cd in rat prostate. METHODS: Cadmium was given to rats at doses of 50, 100, and 200 mg/kg in drinking water. The contents of Zn and Cd in prostate were measured by atomic absorption spectrometry(AAS), and the levels of MTs mRNA were determined by RT-PCR. RESULTS: After Cd administration, the content of Zn was decreased in both the ventral and the dorsolateral lobes of rat prostate. In 200 mg/kg Cd group, the contents of Zn in ventral prostate were 9.5 and 8.5 micrograms/g wet weight respectively after one month and six months, which were significantly lower than those of control(17.0 and 18.9 micrograms/g wet weight). In contrast, the contents of Cd in both ventral and dorsolateral lobes of prostate significantly increased with the increasing dose and time of Cd administration. It was also noted that Cd administration resulted in a significant down-regulation of the expression of MT-I and MT-II mRNA in rat ventral prostate. In 200 mg/kg Cd group after one and six months, the relative expression levels of MT-I (0.410, 0.339 respectively) and MT-II (0.100, 0.112 respectively) were significantly lower than those of MT-I (0.760, 0.830 respectively) and MT-II (0.429, 0.439 respectively) in control group. CONCLUSION: Oral Cd exposure could influence the distribution of Zn and the expression levels of MTs mRNA in rat prostate.

Administration, Oral↗