Cardiorespiratory capacity of Thai workers in different age and job categories.

The objective of this study was to assess the cardiorespiratory capacity of Thai male and female blue-collar workers in different age and occupational categories. The maximal oxygen uptake (VO2max) of 70 men and 56 women was assessed using a submaximal bicycle-ergometer test supplemented with ventilatory gas analyses. The age of the subjects varied from 16 to 55 years.

Ergonomics in practice: physical workload and heat stress in Thailand.

This study consists of assessments of the thermal environment and physiological strain in tasks associated with airport, construction, and metal jobs. The number of male and female participants was 108. Environmental heat stress was evaluated with the WBGT index.

Evaluation of the effect of steviol on chromosomal damage using micronucleus test in three laboratory animal species.

The chromosomal damage activity of steviol, a product of enzymatic alteration of stevioside, a natural non-caloric sweetener was reevaluated by using a bone marrow micronucleus test in both male and female hamsters, rats and mice. The micronucleus test is used widely as a rapid and efficient alternative in chromosome analysis for detecting in vivo cytogenetic damage. Steviol at the dose of 4 g/kg body weight for hamsters and 8 g/kg body weight for rats and mice showed no effect on the frequencies of micronucleus formation in bone marrow erythrocytes of both male and female hamsters, rats and mice.

Developmental toxicity of steviol, a metabolite of stevioside, in the hamster.

The developmental toxicity of steviol, a metabolite of stevioside, was studied in hamsters. Pregnant hamsters were intubated with steviol at dose levels of 0, 0.25, 0.

Lack of mutagenicity of stevioside and steviol in Salmonella typhimurium TA 98 and TA 100.

Stevioside, a sweet-tasting diterpene glycoside derived from Stevia rebaudiana, and steviol, a product from enzymatic hydrolysis of stevioside, were tested for mutagenic activity by the in vitro Ames test, a preincubation method, using Salmonella typhimurium TA 98 and TA 100 as the tester strains, either in the presence or absence of metabolic activating system derived from the sodium phenobarbital and 5,6-benzoflavone pretreated liver S9 fractions from various animal species including rat, mouse, hamster and guinea pig. Stevioside and steviol at the concentrations up to 50 mg and 2 mg per plate, respectively showed no mutagenic effect on both tester strains either in the presence or absence of metabolic activating system. However, at the high concentration both stevioside and steviol showed some toxic effects on both tester strains.