Stature and weight growth, and Heath-Carter somatotypes were studied in two groups of Indonesian children of 7 to 15 years of age. One was an urban Yogyakarta group of 340 boys and 373 girls from well-off families, and the other was a rural Bantul group of 222 boys and 243 girls from low-income families. As for general body size, the Yogyakarta children were taller and heavier than the Bantul children in both sexes. During puberty, the Yogyakarta girls were not larger than the Yogyakarta boys, whereas the Bantul girls had greater stature and weight than the Bantul boys. In the somatochart, the Yogyakarta children before puberty were distributed halfway between endomorphy and mesomorphy in both sexes, and thereafter the boys tended toward ectomorphy and the girls toward endomorphy. The somatotype of the Bantul children remained ectomorphic, but differed by sex with a greater mesomorphic element in the boys and a greater endomorphic element in the girls.

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The EH program for maximum-likelihood (ML) frequencies based on an expectation-maximization (EM) algorithm was employed for re-estimation of the β-globin gene cluster haplotype frequency distributions in Japanese, Koreans, and three Colombian Amerinds (Wayuu, Kamsa, and Inga tribes). The distributions estimated by the EH program (estimation 3) were compared with those of our previous studies obtained from individuals who were homozygous at all polymorphic restriction sites or heterozygous at only one site (estimation 1), or ascertained by family linkage studies in Japanese and Koreans (estimation 2). Average haplotype diversities and Nei’s genetic distances based on estimation 3 were also compared with those based on estimations 1 and 2. Haplotypes of all chromosomes examined, which were based on RFLPs (restriction fragment length polymorphisms) at five or seven sites in the β-globin gene cluster, were determined by the EH program as in the case of a family linkage study. The average haplotype diversities based on estimation 3 were much higher than those based on estimations 1 and 2. The present study based on estimation 3 confirmed the close genetic relationships between Japanese and Koreans, and also between Wayuu and Kamsa. Colombian Amerinds showed some African or European characteristics as well as those of Asians.

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The aim of the present study was to investigate the associations of generalized and central adiposity with established metabolic risk factors for coronary heart disease (CHD) among Bengalee Hindu men of Kolkata, India. A cross-sectional study of 212 Bengalee Hindu men resident in Kolkata, India, was undertaken utilizing four measures of adiposity: body mass index (BMI), waist circumference (WC), waist-hip ratio (WHR), and conicity index (CI). Total cholesterol (TC), high density (HDL-C), low density (LDL-C) and very low density (VLDL-C) cholesterol lipoproteins, fasting blood glucose (FBG) and fasting triglyceride (FTG) levels were recorded. Results revealed that BMI did not have significant correlation with any of the metabolic variables. The Pearson correlation coefficients (r) of the central adiposity measures (WC, WHR and CI) were similar. WC, WHR and CI were significantly correlated (except WC and TC) with TC, VLDL-C, FBG and FTG. However, HDL-C and LDL-C did not show significant correlation with WC, WHR and CI. Regression analyses revealed that WC, WHR and CI had significant impact on TC, VLDL-C, FBG and FTG. All three measures of central adiposity had similar effect. This significant effect remained essentially the same even after controlling for BMI. In conclusion, the present investigation revealed that among Bengalee Hindu men, any one of these three measures (WC, WHR and CI) can be used in cross-sectional epidemiological studies dealing with the relationship of central adiposity and metabolic risk factors for CHD.

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Molar enamel thickness is a key feature in the study of hominid evolution. Our understanding of enamel thickness and distribution patterns, however, has so far been based mostly on the limited information available from physical cross sections of the crown. In this study, the 3-dimensional (3D) whole crown enamel distribution pattern was explored in 74 extant great ape and modern human molars. Serial cross sections obtained from microfocal X-ray computed tomography were used to generate digital molar reconstructions at 50 to 80 micron voxel resolution, each crown represented by two to five million voxels. Surface data of both enamel dentine junction (EDJ) and outer enamel were extracted to derive volumetric measures, surface areas, curvilinear distances, and whole crown radial thickness maps. Three-dimensional average enamel thickness (AET) was defined as enamel volume divided by EDJ surface area. In 3D AET relative to tooth size, Homo exhibited the thickest, Gorilla the thinnest, and Pan and Pongo intermediately thick enamel. This result differs from previous claims that molar enamel of Pongo is relatively thicker than that of Pan. The discrepancy between three and two-dimensional (2D) values of AET stems from a combination of local differences in within tooth enamel distribution pattern and EDJ topography between Pan and Pongo molars. It demonstrates that 2D AET is not an appropriate substitute or estimator of whole crown AET. Examination of whole crown 3D distributions of molar enamel revealed a pattern common to all four examined species, the “functional” side of the molar having thicker enamel than the opposite side. However, some unique aspects of each species were also apparent. While the Gorilla molar has relatively thin enamel throughout its crown, Pan molars are characterized by particularly thin enamel in the occlusal fovea, and Pongo molars by an accentuation of relatively thin basal and thick occlusal enamel. Human molars are characterized by relatively thick enamel throughout the crown, with relatively large contrasts between buccal and lingual, and between mesial and distal crown portions. The ancestral condition common to the four extant species can be estimated by interpreting molar enamel distribution patterns unique to each genus as likely to be derived. We hypothesize that the last common ancestor likely had intermediately thick enamel, without particular thickening (or thinning) of enamel either occlusally or basally.

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In the northwestern Kyushu area, at the southwestern region of the mainland of Japan, a native people of Jomon lineage lived during the Aeneolithic Yayoi period, and differed morphologically from the immigrant people of continental lineage of the northern Kyushu area. In this study, the metric and nonmetric characteristics of 204 modern female crania from northwestern Kyushu were examined in order to investigate their morphological characteristics and lineage relationships by comparing them with several modern Japanese, Ryukyuan, Hokkaido Ainu, Korean, Chinese, and northern and northwestern Kyushu Yayoi and Jomon cranial series. The craniometric characteristics of the northwestern Kyushu Japanese females were found to be similar to those of the mainland Japanese, as well as to those of Koreans, Chinese, and the northern Kyushu Yayoi, but differed somewhat from the Ryukyuan and Hokkaido Ainu conditions, and distinctly diverged from the northwestern Kyushu Yayoi and Jomon conditions. The results of multivariate analyses of nonmetric traits coincided generally with those of the craniometrical analyses; however, the northwestern Kyushu Japanese was found to be relatively close to the Ryukyuans, and markedly remote from the Hokkaido Ainu. These findings suggest that the northwestern Kyushu Japanese possess morphological traits in common with other mainland Japanese populations due to genetic influences of the continental lineage during or after the protohistoric Kofun period.

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This study reevaluates the relationship between the prehistoric Jomon and modern Ainu based on 18 nonmetric cranial traits. Although the two Ainu series from the northeast coast and central/southern regions of Hokkaido Island are always associated with Jomon, significant differences between the Ainu and Jomon were detected in the frequencies of seven traits: metopism, supraorbital foramen, ovale–spinosum confluence, hypoglossal canal bridging, jugular foramen bridging, biasterionic suture vestige, and occipitomastoid bone. Regarding these traits, the Ainu series are more similar to the Okhotsk than to the Jomon series. A broad comparison among pan-Pacific populations confirms the maintenance of distinctive morphologies in the remote regions of group ranges, as represented by the Jomon and to a lesser extent the recent Hokkaido Ainu. The Ainu occupies an intermediate position between Jomon and Northeast Asians on the one hand, and between Jomon and the Native Americans on the other. The pattern of temporal change between Jomon and Ainu, together with clinal variation among the three Ainu series from Sakhalin Island, the northeast Hokkaido coast, and central/south Hokkaido shown in the present study, indicate possible admixture between the ancestors of recent Ainu and northern groups such as the Okhotsk people in the post-Jomon periods.

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JC virus (JCV) is ubiquitous in the human population, usually being transmitted from parents to children during cohabitation. JCV genotyping is a useful means of elucidating the origins of various ethnic groups in the world. We used this method to gain insights into the origin of the Mamanwa, a Philippine Negrito tribe in Northeast Mindanao. We found that the Mamanwa carried two major JCV genotypes, B3-b/2E and SC-f/7A. This was in contrast with the JCV genotype profile of modern Filipinos who carry up to five genotypes, with B3-b/2E showing only a low frequency. B3-b/2E is spread throughout Oceania but rare on the Asian continent. In contrast, SC-f/7A is spread throughout Southeast Asia (including neighboring Oceanic islands) but rare in Remote Oceania. The present findings thus suggest that the Mamanwa tribe was formed by early colonization by people carrying B3-b/2E followed by an admixture of more recent immigrants carrying SC-f/7A. As the indigenous tribe (the Chamorro) in the Mariana Islands has essentially the same JCV genotype profile as the Mamanwa, other indigenous tribes in Southeast Asian and Oceanic islands may have a population history analogous to that suggested for the Mamanwa.

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The body mass index [BMI = body weight/height² (kg/m²)] is widely used as an indicator of obesity. However, BMI is not the best way to assess obesity, because obesity is an excess of body fat, not body weight. The difference between obesity assessments based on BMI and those based on the percentage of body fat (%Fat) causes problems in evaluating extraordinarily large people, such as Sumo wrestlers, who have both a large fat mass and a large muscle mass. We assessed obesity in male college Sumo wrestlers (n = 15) and non-athlete students (n = 20) using BMI and %Fat as reference indices. Anthropometric parameters and resting metabolic rate (in the sitting position) were measured. The mean body weight, BMI, and %Fat for Sumo wrestlers were 125.1 kg, 40.0, and 25.6%, respectively, which were extraordinarily high, as compared to non-athlete students (P < 0.01). All of the Sumo wrestlers were categorized as obese using the BMI criteria proposed by the World Health Organization: eight were ‘severely obese’ (35 ≤ BMI < 40) and seven were ‘very severely obese’ (BMI ≥ 40). However, only 40% of the wrestlers (n = 6) were categorized as obese when %Fat was used as the reference (%Fat > 25%). Furthermore, the body composition chart clearly showed that some Sumo wrestlers were no more adipose than the non-athlete students. Due to their remarkable muscle development, Sumo wrestlers have an excessive fat-free mass. Thus we conclude that it is necessary to consider both BMI and %Fat to assess obesity in excessively muscular people, such as Sumo wrestlers. Furthermore, we propose new criteria and methods for documenting obesity in Sumo wrestlers based on energy metabolism that considers physical activity and dietary intake.

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Two new methods that accurately analyze the displacement velocity of the center of pressure (COP) in order to diagnose postural control systems are presented: a wavelet analysis method and a method that analyzes the distribution of COP displacement velocity. Both methods could easily detect a transient but significant phenomenon in a series of COP swings. Recovery training based on diagnoses made by these methods should enable individuals to maintain effectively their postural control systems. As it is important to prevent potentially fatal accidents from falls involving elderly people, the two methods presented have much to contribute to aging societies in developed countries.

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