(WHO, 1998). It was suggested that Japanese, categorized as having normal weight (BMI of less than 25.0), as defined by the WHO (2000), have an increasing tendency toward metabolic syndrome. Our objective was to analyze metabolic syndrome in "Overweight" with BMI of 23.0-24.9 in Japanese workers, and to assess the suitability for Asians of the Regional Office for the Western Pacific Region of WHO criteria pertaining to obesity (WPRO criteria, 2000). We conducted a cross-sectional study in the workplace setting and investigated the relationship between BMI classification based on WPRO criteria and metabolic syndrome by gender and age group (18-44 yr vs. 45-60 yr). Three hundred seventy-nine men and 432 women Japanese workers participated in this study. BMI were categorized as 20% "Overweight" (23.0-24.9 BMI), 20% "Obese I" (25.0-29.9 BMI) and 2% "Obese II" (over 30.0 BMI), based on WPRO criteria. Graded increases in BMI were positively associated with body fat percentage, waist circumference, hip circumference and waist/hip Received April 30, 2003; Accepted Aug 21, 2003 Correspondence to: K. Shiwaku, Department of Environmental and Preventive Medicine, Shimane University School of Medicine, Izumo City, Shimane, Japan ratio in both genders and age groups. A progressively increasing BMI category in the elder group aged 45-60 yr in both genders was positively related with parameters constituting metabolic syndrome. Graded increases in BMI classes in elder workers based on WPRO criteria were positively associated with prevalence of metabolic syndrome, and "Overweight" elder women had significantly higher prevalence of metabolic syndrome. The present investigation, based on the increasing risks of "Overweight" with a BMI of 23.0-24.9, suggests that WPRO criteria are suitable for Japanese workers aged over 45 yr. (J Occup Health 2003; 45: 335-343)

OBJECTIVE:The degree of obesity of Asians is less than that of Caucasians. It has been suggested that Japanese, categorized as having normal weight (BMIo25.0), as defined by WHO (2000), have a tendency toward increased incidences of dyslipidemia and diabetes. Our objective was to analyze parameters constituting obesity-associated disorders in overweight Japanese and Mongolians with a body mass index (BMI) of 23.0-24.9, and to assess the suitability for Asians of the Regional Office for Western Pacific Region of WHO criteria pertaining to obesity (WPRO criteria, 2000). DESIGN: Cross-sectional study in a workplace setting. SUBJECTS: A total of 386 Japanese men and 363 Japanese women, and 102 Mongolian men and 155 Mongolian women. MEASUREMENTS: Anthropometric measurements (weight, height, waist circumference, hip circumference and blood pressure) and metabolic measurements (plasma levels of total cholesterol, HDL cholesterol, triglyceride, glucose and insulin). RESULTS: Graded increases in BMI of Japanese and Mongolians were positively associated with body fat percent, waist circumference, hip circumference and waist/hip ratio. The Japanese were categorized as 22% overweight, 22% obese I, 3% obese II; the Mongolians rated as 18% overweight, 34% obese I, 19% obese II, based on the WPRO BMI criteria. The Mongolians had a higher prevalence of obesity and a higher body fat percent, but a lesser gradation of dyslipidemia, than did the BMImatched Japanese groups. Overweight Japanese (BMI 23.0-24.9), in comparison to normal Japanese (BMI 18.5-22.9), had significant differences in systolic blood pressure, HDL-choresterol and triglyceride in men, and in systolic and diastolic blood pressure, HDL-choresterol, triglyceride, insulin and Homoeostasis model assessment-insulin resistance in women. In contrast, the Mongolians showed no significant differences in metabolic parameters between overweight and normal subjects, except for diastolic blood pressure. CONCLUSION: Since the relationship between abdominal fat mass and BMI is ethnic-specific, a universal BMI cutoff point is inappropriate for Asian populations such as the Japanese and Mongolians. The present investigation suggests that, while the WPRO criteria are suitable for Japanese, the WHO criteria are more appropriate for Mongolians.

OBJECTIVE: Trp64Arg mutation in the b 3 -adrenergic receptor (b 3 AR) gene is relatively common in Japanese people. However, it has not been clear whether persons with Trp64Arg mutation in the b 3 AR gene tend to have obesity and difficulty in losing weight even with a restricted diet and exercise. We investigated the response of body weight and metabolic factors to behavioral intervention in Japanese women with Trp64Arg mutation in the b 3 AR gene. DESIGN: A 3-month behavioral intervention study using a combination of diet and exercise programs. SUBJECTS: A total of 76 perimenopausal women with no clinical symptoms (age: 54.777.7 y, body mass index (BMI): 21.0-33.0 kg/m 2 ). MEASUREMENTS: Anthropometric measurements (weight, height, body fat, waist circumference, hip circumference, skin fold, resting energy expenditure and blood pressure) and metabolic measurements (serum levels of cholesterol, triglyceride, phospholipid, nonesterified fatty acid, glucose, insulin and leptin) and determination of the b 3 AR genotype by polymerase chain reaction followed by BstNI digestion. RESULTS: At the baseline of BMI, body weight, body fat, waist circumference, hip circumference, the arm skin fold, resting energy expenditure, or blood lipid and glucose profiles, there was no significant difference in participants with/without mutation of the b 3 AR gene. The intervention yielded a body weight reduction in 69 and 48%, and induced a significant difference in weight loss (À0.74 and À0.01 kg) for women with wild-type and Trp64Arg mutation, respectively. Significant differences of anthropometric parameters were found in body weight, BMI, waist and hip circumferences and blood pressure of wild type by the intervention. However, women with Trp64Arg mutation did not show significant changes in these anthropometric parameters, except for hip circumference. A significant difference was found in high-density lipoprotein cholesterol (HDL-C) and in the low-density lipoprotein cholesterol/HDL-C ratio in both genotypes. CONCLUSION: The results of the present study suggest that the Trp64Arg mutation of the b 3 AR gene is associated with difficulty in losing weight through behavioral intervention, although it is not related to obesity-related phenotypes and resting energy expenditure before the intervention.

The extracellular chitosanase (34,000 M r) produced by a novel gram-negative bacterium Matsuebacter chitosanotabidus 3001 was purified. The optimal pH of this chitosanase was 4.0, and the optimal temperature was between 30 and 40°C. The purified chitosanase was most active on 90% deacetylated colloidal chitosan and glycol chitosan, both of which were hydrolyzed in an endosplitting manner, but this did not hydrolyze chitin, cellulose, or their derivatives. Among potential inhibitors, the purified chitosanase was only inhibited by Ag+. Internal amino acid sequences of the purified chitosanase were obtained. A PCR fragment corresponding to one of these amino acid sequences was then used to screen a genomic library for the entire choA gene encoding chitosanase. Sequencing of the choA gene revealed an open reading frame encoding a 391-amino-acid protein. The N-terminal amino acid sequence had an excretion signal, but the sequence did not show any significant homology to other proteins, including known chitosanases. The 80-amino-acid excretion signal of ChoA fused to green fluorescent protein was functional in Escherichia coli. Taken together, these results suggest that we have identified a novel, previously unreported chitosanase.

Mitsuaria chitosanitabida gen. nov., sp. nov., an aerobic, chitosanase-producing member of the 'Betaproteobacteria' T , 12 and 13 were found to occupy a separate position in the 'Betaproteobacteria'. Roseateles depolymerans, Rubrivivax gelatinosus and Ideonella dechloratans were their closest neighbours (93-95 % 16S rRNA gene sequence similarity). The 16S rRNA gene sequence and other characteristics suggested that strain 2 belonged to the genus Flavobacterium. DNA-DNA hybridization experiments supported the conclusion that strains 3001 T , 12 and 13 were of the same species (72-78 % DNA hybridization) and only distantly related to I. dechloratans and R. gelatinosus. It is proposed that strains 3001 T