Correlations of urinary cadmium with hypertension and diabetes in persons living in cadmium-contaminated villages in northwestern Thailand: A population study

Risk for hypertension and diabetes has not been conclusively found to be a result of cadmium exposure. A population-based study was conducted in 2009 to examine the correlations of urinary cadmium, a good biomarker of long-term cadmium exposure, with hypertension and diabetes in persons aged 35 years and older who lived in the 12 cadmium-contaminated rural villages in northwestern Thailand. A total of 5273 persons were interviewed and screened for urinary cadmium, hypertension, and diabetes. The geometric mean level of urinary cadmium for women (2.4±2.3 μg/g creatinine) was significantly greater than that for men (2.0±2.2 μg/g creatinine). Hypertension was presented in 29.8% of the study population and diabetes was detected in 6.6%. The prevalence of hypertension significantly increased from 25.0% among persons in the lowest tertile of urinary cadmium to 35.0% in the highest tertile. In women, the rate of hypertension significantly increased with increasing urinary cadmium levels in both ever and never smokers, after adjusting for age, alcohol consumption, body mass index, and diabetes. In men, such association was less significantly found in never smokers. The study revealed no significant association between urinary cadmium and diabetes in either gender. Our study supports the hypothesis that environmental exposure to cadmium may increase the risk of hypertension. Risk for diabetes in relation to cadmium exposure remains uncertain in this exposed population.     

Increased platelet activation in subjects chronically exposed to cadmium: A pilot study

Cadmium exposure has been reported to be associated with the risk of vascular disorders. Here, we investigated platelet activity in subjects with chronic cadmium exposure. Eighteen and 15 women participated in this study as chronically cadmium-exposed and control non-exposed subjects, respectively. Plasma P-selectin and CD40 ligand (CD40L), soluble markers of platelet activation, were measured. Platelet aggregation in whole blood, P-selectin and activated glycoprotein (aGP) IIb/IIIa expression on platelets and platelet–leukocyte aggregates were determined. The levels of plasma P-selectin and CD40L increased in subjects with chronic cadmium exposure compared with control subjects. Platelet aggregation induced by adenosine diphosphate (ADP) was higher in cadmium-exposed subjects than control subjects. Cadmium-exposed subjects had higher baseline and ADP-induced aGPIIb/IIIa expression on platelets than control subjects. Platelet–neutrophil aggregates also increased in cadmium-exposed subjects. Blood cadmium correlated with ADP-induced aggregation, aGPIIb/IIIa expression and platelet–neutrophil aggregates, while urinary cadmium correlated with soluble P-selectin. However, cadmium only at high concentration (15?µM) could potentiate ADP-induced platelet activation in vitro. In conclusion, our pilot data show that cadmium-exposed subjects have increased baseline platelet activation and reactivity.     

Modifying influence of dehydroepiandrosterone on the development of dihydroxy-di-n-propylnitrosamine-initiated lesions in the thyroid, lung and liver of F344 rats

Following initial treatment of F344 rats with dihydroxy-di-n-propyinitrosamine,exposure to dehydroepiandrosterone (DHEA) administered in thediet at a concentration of 0.6% brought about significant decreasein weight gain, independent of food consumption, and inhibitedthe development of thyroid tumors and hepatocyte-altered enzymefoci. In addition to inducing a diffuse increase in glucose-6-phosphatasedehydrogenase (G6PD) and gammaglutamyl transpeptidase in theliver. DHEA treatment was associated with development of smallnumbers of basophilic hepatocellular foci which differed markedlyin enzyme phenotype from the clear cell (glycogen storing) lesionspredominating in the carcinogen-treated animals maintained onbasal diet. The results are consistent with the concept thatDHEA-modification of neoplastic development, as reported earlierin a number of different organs and here in the liver and thyroid,may be in some way partly mediated by changed expression ofthe key enzyme of the pentose phosphate pathway, G6PD, and relatedmetabolic systems. Heterogeneity in the quality of initiatedhepatocytes with regard to capacity for inhibition or promotionindicated by the present data point to the existence of morethan one pathway to tumour development in the rat liver.     

What World Health Assembly Resolution 60.22 Means to Those Who Care for the Injured

On May 23, 2007, the World Health Assembly (WHA) adopted WHA Resolution 60.22, "Health Systems: Emergency Care Systems," which called on the World Health Organization (WHO) and governments to adopt a variety of measures to strengthen trauma and emergency care services worldwide. This resolution constituted some of the highest level attention ever devoted to trauma care worldwide. This article reviews the background of this resolution and discusses how it can be of use to surgeons, emergency physicians, and others who care for the injured, especially in low- and middle-income countries.     

Leptospirosis in Kamphaeng Phet, Thailand

Leptospirosis, which is caused by pathogenic spirochetes of the genus Leptospira, is a zoonotic disease of global importance and an emerging health problem. We studied patients suspected of having leptospirosis in Kamphaeng Phet Province, Thailand. Of 106 patients with suspected leptospirosis evaluated at the provincial hospital, 69 (65%) were confirmed positive (titer > or = 1:800 or > or = 4-fold increase in titer) by microscopic agglutination testing. Seventy-seven percent (53) of the cases occurred during the rainy season (June through November). Sera reacted predominantly with Bratislava, Autumnalis, and Icterohaemorrhagiae serovars. The screening Leptospira Dip-S-Ticks test had poor sensitivity (32%) but a specificity of 100% compared with a Leptospira IgM enzyme-linked immunosorbent assay. Leptospirosis was found to be a frequently confirmed cause of morbidity in Kamphaeng Phet Province in those suspected of having the illness.     

Effect of motorcycle rider education on changes in risk behaviours and motorcycle-related injuries in rural Thailand

A community-based programme for motorcycle rider education was provided for motorcyclists in all villages of 3 randomly selected subdistricts in Mae Sot District, Tak Province, northern Thailand, between January and March 1995. To determine the extent of changes in risk-taking behaviours, we conducted an interview survey of motorcyclists in 3 villages selected by systematic sampling from the 3 intervention subdistricts and in 3 control (without intervention) villages for comparison in March 1997, 2 years after the programme. Motorcyclists in the intervention villages (69.7%) were significantly more likely to have valid licences than those in the control villages (46.5%). The proportion of motorcyclists who always or often wore helmets was significantly greater in the intervention sample (46.0%) than in the control sample (20.5%). In 1994, the annual incidence rate of motorcycle-related injuries was slightly higher in the intervention areas than in the control areas. Following the education programme, the injury rates for 1995 and 1996 were significantly lower in the intervention than in the control population. The annual number and rate of fatal motorcycle injuries decreased after the intervention although there was no significant difference between the two populations. Motorcycle rider education may be a promising intervention for prevention of motorcycle-related injuries in rural areas where road safety measures, particularly enforcement activities, are commonly limited.     

Promotion of Rat Hepatocarcinogenesis by Praziquantel

Praziquantel, the widely used anti-helminthic agent, was investigated for hepatocarcinogenesis-promoting potential using a medium-term liver bioassay system for carcinogens. F344 male rats were given a single intraperitoneal injection of diethylnitrosamine (DEN, 200 mg/kg) and then starting 2 weeks later, received praziquantel in the diet at concentrations of 1.5 or 0.5%, or intragastrically at a dose of 1,500 mg/kg once a week for 6 weeks. Control groups received DEN or praziquantel alone. All rats were subjected to two-thirds partial hepatectomy at week 3 and killed at week 8. Development of glutathione 5-transferase placental form-positive foci in the liver was significantly increased in terms of both number and area with the 1.5% dose, while only area was affected by the 0.5% dose. The results thus indicate that praziquantel at high dose has promoting potential in rat hepatocytic tumorigenesis.     

Modification by five antioxidants of 1,2-dimethylhydrazine-initiated colon carcinogenesis in F344 rats

The effects of antioxidants given in the post initiation phaseof colon tumor development were investigated in male F344 ratstreated with 1 ,2-dimethylhydrazine (DMH). Animals (20/group)were given s.c. injections of DMH at a dose of 20 mg/kg oncea week for four consecutive weeks. One week after the last injection,rats were fed diet containing 5% sodium L-asorbate (SA), 0.5%butylated hydroxyanisole (BHA), 0.8% ethoxyquin (EQ), 1.0% propylgallate or 0.5% butylated hydroxytoluene (BHT) for 36 weeks.A control group was fed the basal diet not containing antioxidants.The experiment was terminated 40 weeks after the first injectionof DMH and all intestinal tumors were confirmed histologically.SA significantly increased the incidence of adenomas and thenumber of tumors per rat of the colon (especially of the distalcolon). Although EQ and BHT did not affect the number of ratswith colon tumors, the number of tumors per rat occurring inthe distal colon was significantly increased by EQ while beingdecreased by BHT. No modification of tumor development was observedwith BHA or PG. Thus, modification of tumor development by SA,EQ and BHT was apparent, mainly in the distal colon.     

Fractional excretion of calcium,a sensitive marker for calcium wasting in cadmium-exposed women

In Cadmium (Cd)-exposed populations there is urinary calcium (Ca) loss which reflects Ca loss from the bone, decreased bone mass, and osteoporosis later in life, to which women are particularly vulnerable. A sensitive screening method to detect critical Ca wasting is required to provide warning of an increased osteoporosis risk. We used Fractional Excretion of Calcium (FECa) to study Ca wasting in Cd-exposed population. FECa sensitivity to Ca loss was compared to that of serum Ca, urinary Ca and intact parathyroid hormone. Mean FECa in the exposed group was 1.5 times higher than in the control group, and a dose-effect relationship to Cd exposure level was observed. FECa showed a relationship to Cd exposure level even following adjustment for a renal dysfunction marker. We conclude that FECa has a better sensitivity than urinary Ca and serum Ca. The use of FECa as an indicator of Ca wasting in Cd exposed women is recommended.