Brief communication: Body mass index,body adiposity index,and percent body fat in asians

Human obesity is a growing epidemic throughout the world. Body mass index (BMI) is commonly used as a good indicator of obesity. Body adiposity index (BAI = hip circumference (cm)/stature (m)^1.5 ? 18), as a new surrogate measure, has been proposed recently as an alternative to BMI. This study, for the first time, compares BMI and BAI for predicting percent body fat (PBF; estimated from skinfolds) in a sample of 302 Buryat adults (148 men and 154 women) living in China. The BMI and BAI were strongly correlated with PBF in both men and women. The correlation coefficient between BMI and PBF was higher than that between BAI and PBF for both sexes. For the linear regression analysis, BMI better predicted PBF in both men and women; the variation around the regression lines for each sex was greater for BAI comparisons. For the receiver operating characteristic (ROC) analysis, the area under the ROC curve for BMI was higher than that for BAI for each sex, which suggests that the discriminatory capacity of the BMI is higher than the one of BAI. Taken together, we conclude that BMI is a more reliable indicator of PBF derived from skinfold thickness in adult Buryats. Am J Phys Anthropol 152:294–299, 2013. © 2013 Wiley Periodicals, Inc.     

Measurement of body composition in response to a short period of overfeeding

Background

Obesity and overweight are increasing in prevalence in developed countries as a result of changing dietary habits and a lack of physical activity. The purpose of the present study was to evaluate the changes in body composition during short-term overfeeding using the three-component model, which is composed of fat mass (FM), total body water (TBW), and fat-free dry solids (FFDS).

Methods

Ten healthy men completed 3 days of overfeeding during which they consumed 1,500 kcal/day more energy than consumed in their normal diets. Body composition was evaluated at three time points: the day before and after their normal diets and the day after the 3-day overfeeding diet.

Results

Before and after their normal diets, there were no significant differences in body weight and composition, but after 3 days of overfeeding, body weight, TBW, and FFDS increased 0.7, 0.7, and 0.2 kg, respectively (P <0.0001). There was no significant difference in FM between the normal and overfeeding diets.

Conclusion

This study suggests that TBW gain contributes to weight gain following a short-term overfeeding.     

Socio-economic factors and body composition

This study supplies further data to the question of influence of social background in body development. There are a great number of studies concerning the influence of socio-economic factors on growth. On the other hand, there are very few investigations into the factors of body composition though these factors give more information about the developmental stage of the children's skeleton, muscle and fat mass than any absolute measurement. The social status was established on the basis of the parents' occupation, educational level, the per capita income, per capita room-quota and sibling number. Beyond these factors the effects of maternal age at childbirth and birth order were investigated in a sample of 3553 boys and 3371 girls aged between 7–14. Body composition was studied by a two-component model. Results of body composition have shown that children living under better social circumstances are not only heavier, because they have more developed skeleton and musculature, but have more body fat mass too. The excess of their body fat mass is caused in part by the unaltered habits of nutrition, in part by sedentary life style. These results stress the necessity for a more efficient somatic and environmental education.     

包含体蛋白质的复性研究进展

包含体的形成是异源蛋白质在大肠杆菌中高效表达的必然结果,也是目前产生重组蛋白质最有效的方法之一。不可溶、无生物活性的包含体必须经过变性、复性才能获得天然结构,完整特定的生物学功能。聚集是造成重组蛋白质复性产率低下的主要因素,因此理解蛋白质聚集机制,减少和防止聚集的发生是建立高效、高产率复性方法的关键。分子伴侣、低分子量添加物等在复性过程中的应用及新的复性方法的建立都大大提高了重组蛋白质复性产率。     

Scaling of body frontal area and body width in birds

By analyzing a homogenous dataset we show, in contradiction to a previous study, that the scaling of body frontal area (S(b)) with body mass (m(b)) does not differ between passerine and nonpasserine birds. It is likely that comparison of data collected from live passerines with data collected from frozen nonpasserines had led to the incorrect conclusion that the scaling of S(b) varied between the taxa. We suggest that body dimensions collected from frozen specimens, or specimens stored in alcohol, are not applicable to live birds, and that both the current equations presented in the literature for predicting S(b) from m(b) may lead to inaccurate estimates. Using data from preserved specimens, we found that S(b) scales isometrically with m(b) (S(b) proportional, variant m(b) (0.66)), and therefore we found no evidence for larger birds being more streamlined than smaller birds. S(b) scales with negative allometry against wingspan (b), however, and b scales with positive allometry against m(b), so larger birds have smaller S(b) relative to b. In addition, it appears that dorsoventral flattening of the body is a general characteristic of bird's bodies but that it is more pronounced in larger birds, suggesting perhaps a function in terms of increased lift during forward flight. It appears that bird's bodies obey the surface-to-area geometric scaling law, but bird body shape may vary in relation to aerodynamic function. We suggest that a large-scale study, simultaneously measuring S(b) and m(b) in live passerines and nonpasserines, is required to improve the predictive power of S(b) upon m(b) scaling equations, which play a key role in the estimation of mechanical power consumption in flight in birds. Furthermore, the relations between bird body shape and axial skeleton dimensions, with reference to aerodynamic adaptation, warrant further investigation.     

Estimating body mass in subadult human skeletons

Methods for estimating body mass from the human skeleton are often required for research in biological or forensic anthropology. There are currently only two methods for estimating body mass in subadults: the width of the distal femur metaphysis is useful for individuals 1–12 years of age and the femoral head is useful for older subadults. This article provides age‐structured formulas for estimating subadult body mass using midshaft femur cross‐sectional geometry (polar second moments of area). The formulas were developed using data from the Denver Growth Study and their accuracy was examined using an independent sample from Franklin County, Ohio. Body mass estimates from the midshaft were compared with estimates from the width of the distal metaphysis of the femur. Results indicate that accuracy and bias of estimates from the midshaft and the distal end of the femur are similar for this contemporary cadaver sample. While clinical research has demonstrated that body mass is one principle factor shaping cross‐sectional geometry of the subadult midshaft femur, clearly other biomechanical forces, such as activity level, also play a role. Thus formulas for estimating body mass from femoral measurements should be tested on subadult populations from diverse ecological and cultural circumstances to better understand the relationship between body mass, activity, diet, and morphology during ontogeny. Am J Phys Anthropol 143:146–150, 2010. © 2010 Wiley‐Liss, Inc.     

Regional body volumes, BMI, waist circumference, and percentage fat in severely obese adults

Objective: This study presents total body volume (TBV) and regional body volume, and their relationships with widely used body composition indices [BMI, waist circumference (WC), and percentage body fat (% fat)] in severely obese adults (BMI ≥35 kg/m²). Research Methods and Procedures: We measured TBV, trunk volume (TV), arm volume (AV), leg volume (LV), and WC and estimated % fat in 32 severely obese persons with BMI 36 to 62 kg/m² (23 women; age, 19 to 65 years; weight, 91 to 182 kg) and in 58 persons with BMI <35 kg/m² (28 women; age, 18 to 83 years; weight, 48 to 102 kg) using a newly validated 3‐day photonic image scanner (3DPS, Model C9036–02, Hamamatsu Co., Japan) and calculated TV/TBV, AV/TBV, and LV/TBV. Results: Men had significantly larger TBV and higher TV/TBV and AV/TBV, but significantly lower LV/TBV than women, independently of BMI. TV/TBV increased while AV/TBV and LV/TBV decreased with increasing BMI, WC, and % fat, and the rate of increase in TV/TBV per % fat was significantly greater in severely obese individuals than in individuals with BMI <35 kg/m². The relationships for TBV with % fat were much lower than with BMI or WC. Conclusion: Body volume gains were mainly in the trunk region in adults, irrespective of sex or BMI. For a given BMI, WC, or % fat, men had a significantly larger TV than women. The implication is that men could have higher health risks due to having higher trunk body weight as a proportion of total body weight compared with severely obese or less severely obese women.     

Age variations in the relation of body mass indices to estimates of body fat and muscle mass

In some chronic disease studies, distinctions have been made regarding the importance of body mass index (BMI) as a risk factor in younger versus older men and women. In order to determine the significance of these differences in BMI-disease associations, we determined the extent of age-dependent variations in the relation of BMIs to body composition in large probability samples of U.S. men and women from the First and Second U.S. National Health and Nutrition Examination Surveys (NHANES I and II). BMIs are more highly correlated with estimates of body fat in younger than in older men and women, and with muscle mass in older than in younger adults. Caution should be exercised in interpreting the significance of BMI as a risk factor for chronic disease, particularly in comparison of age groups.     

军队院校毕业班学员的人体成分检测

目的：通过测量军校毕业学员的人体成分,探讨军校毕业学员与普通居民的区别,并为建立相关标准提供依据。方法：按飞行院校、分流院校、合训院校、技术院校和士官学校分层抽取5968名毕业学员,分别进行人体成分检测,根据结果划定5%-95%分布上下限。并就军校毕业学员的体脂百分比、体质指数（BMI）、肌肉百分比、骨质百分比指标与同年龄、同性别城乡居民进行比较。结果：1军队院校毕业学员体脂百分比的参考值范围为10.3%-20.7%（男）和19.2%-30.1%（女）;BMI参考值范围为19.30-25.70（男）和18.00-23.99（女）;瘦体重百分比参考值范围为79.3%-86.7%（男）和69.9%-80.7%（女）;肌肉百分比参考值范围为74.2%-84.0%（男）和65.2%-75.3%（女）;骨质百分比参考值范围为5.0%-5.8%（男）和4.7%-5.5%（女）。2与同年龄、同性别城乡居民比较,军队院校毕业学员的体脂百分比明显较少,肌肉百分比、骨质百分比明显较高。结论：1军队院校毕业学员的身体成分数据明显优于同年龄、同性别城乡居民,总体表现为体脂较少,肌肉和骨质较多。2军队院校毕业学员的体质状况不能简单采用民用标准,需建立一套符合军校毕业学员的标准。     

Calcium binding sites in the vesicles of the carotid and aortic body chief cells

Summary Chief cells of the carotid and aortic body chemoreceptors possess numerous cytoplasmic dense-core vesicles which are known to contain primarily dopamine. Following fixation in solutions containing 50 mM CaCl₂, a 20–30 nm electron-dense particle (EDP) is often observed eccentrically located in many of the vesicles. Approximately 44 % of the carotid body and 16 % of the aortic body vesicles contain an EDP. The EDP probably represents the Ca^{+ +} binding site critical to the stimulus-secretion coupling events culminating in exocytosis of these vesicles. The presence of Ca^{+ +} in the cytoplasmic vesicles was verified by electron probe X-ray microanalysis.Supported by a Grant-in-Aid from the American Heart Association (77630) and by funds contributed in part by the Texas Affiliate. The authors wish to thank Ms. Teri Heitman for her excellent technical assistance     

Allometry of head and body size in Holocene foragers of the South African Cape

Opportunities to assess morphological allometry in small-bodied human populations are rare. The foragers of the Later Stone Age of the South African Cape are characteristically small-bodied. Previous studies have shown that during the period of ca. 3500 to 2000 years BP (uncalibrated (14) C dates), the regional population shows transient reduced stature, body mass, and cranial size, a pattern that has been tentatively tied to demographic pressure on resources. This study examines the relationships among cranial size (centroid size) and body size (femoral length, femoral head diameter, and bi-iliac breadth) during the second half of the Holocene (N = 62). Reduced major axis regression indicates negative allometry of cranial centroid size with body size. Residuals (from ordinary least squares regression of cranial centroid size on body size) are regressed on radiocarbon date to examine temporal changes in the relationship between cranial and body size. Cranial and pelvic sizes are most conserved through time, while more ancient skeletons possess shorter femora and smaller femoral heads. The relationship between cranial centroid size and femoral length shows larger and more variable residuals at more recent dates, indicating a greater or more variable disassociation between cranial size and stature relative to more ancient skeletons. A similar, but nonsignificant relationship exists between cranial size and bi-iliac breadth. These results provide insights into the use of aspects of body size and proportionality in the assessment of health in past populations.     

间断下体负压暴露方式对下体负压耐力的影响

目的：探讨不同方式反复下体负压锻炼对下体负压耐力的影响,以期筛选最佳的负压锻炼方式。方法：27名男性健康受试者随机分成3组,分别进行－5.33kPa8min(A组）、6.67kPa4min（B组）、6.67kPa8min（C组）的下体负压锻炼后累积应激指数（CSI）、总耐受时间（DNP）较锻炼前显著提高,A、B组上述指标无显著变化,下体负压暴露时的心率较平静状态显著升高,收缩压显著降低,舒张压无显著变化。结论：经过－6.67kPa/d8min连续8d的间断下体负压可以显著提高下体负压耐力。     

黑带食蚜蝇体色变异的研究

通过对黑带食蚜蝇Episyrphus balteatus(De Geer)体色变异的研究,发现黑带食蚜蝇存在深色型和浅色型2种基本形式,体色变异具有明显的季节性,深色型个体出现在温度较低的秋季及早春,浅色型个体发生在温度较高的春夏季节;在腹部色斑方面,深色型和浅色型个体中均存在变异,可划分为8种类型,腹部色斑的变异在浅色型个体中较为丰富,腹部不同体节背板上色斑的变异程度不同;黑带食蚜蝇在体型大小方面同样存在差异,这些变异的多态性可能是食蚜蝇系统学研究中异名产生的一个重要原因。因此,食蚜蝇类群的个体体色变异在系统学研究中是一个必须特别注意的问题。     

Secular changes in body formation of greek students

Anthropometric dimensions of 1520 students of Biology at University of Athens in Greece were analysed to determine secular changes of height and body proportions during a 20 year period. Since, 1970, means of standing height, subischial length, and cormic index have been increased, although the rate of increase from 1986 to 1990 has been rather slow. On the contrary the mean sitting height is stable, and cormic/ subischial index have been declined during the same period. There are no data for comparing this sample with the general population, but we suppose that these changes in the body formation is common as a result of the modern way of life.     

人体成分研究概览

近年来,我国体成分的研究取得了可喜的进步。为了庆贺吴新智院士九十华诞并回应学者们在中国解剖学会人类学专业委员会(呼和浩特)召开的体成分会议上提出的问题,推动我国体成分的研究,本文搜集了国人1985年以来在国内外发表的730篇体成分方面的研究文献,内容涵盖研究方法及其有效性、体成分的应用、人的体成分的差异以及理论等方面并与当前国际最新研究进展进行对照分析,找出我们的差距并提出今后的建议。     

富营养化水体生物净化效应的研究进展

水体富营养化治理已成为当今世界性难题,解决水体富营养化问题的关键是调控水生生态系统结构,使其恢复自然、健康和稳定的水生生态系统功能,提高水生生态系统的生物净化能力,水生高等植物及水生植被是水生生态系统中最重要的初级生产者,它们个体大、生长周期长、吸取和储存营养物质的能力强,保持和恢复一定数量的水生植物种群可抑制浮游植物的生长,提高系统的生物多样性,使水生生态系统结构更加稳定,水生动物在水生生态系统物质和能量循环中处于十分重要的地位,浮游动物和底栖动物可直接捕食浮游植物,控制浮游植物的数量;而改变鱼类种群结构可提高浮游动物的生物量,从而间接控制浮游植物的大量繁殖,达到治理水体富营养化的目的,我国的生物净化研究还处于起步阶段,今后在水生高等植物及水生植被生物净化的关键技术及优化水产养殖新模式技术研究方面有待提高,这将对我国水体富营养化治理及水体可持续利用有着重要的意义。     

Molecular forms of soluble HLA in body fluids: potential determants of body odor cues

The major histocompatibility complex (MHC) has been linked to encoding for individual olfactory identity. Experiments in mice and rats proved that behavior and mating were, at least in part, determined by genes within the MHC. This study was aimed at investigating whether sHLA are excreted in human urine, saliva and sweat. In particular examination of the molecular forms in these fluids would give clues to whether break down forms of soluble MHC molecules might participate in shaping behavior. Major bands of 45, 40, and 23 kD were detectable. Increased levels of sHLA were measured using a quantitative ELISA in urine shortly before ovulation decreasing to normal levels thereafter. In animal models strain specific MHC‐linked odor cues have been detected in urine. Thus, excretion of sHLA in urine might indicate a similar role for these molecules in humans. This revised version was published online in July 2006 with corrections to the Cover Date.     

The evolution of body armor in mammals: plantigrade constraints of large body size

Predictions associated with opposing selection generating minimum variance in basal metabolic rate (BMR) in mammals at a constrained body mass (CBM; 358 g) were tested. The CBM is presumed to be associated with energetic constraints linked to predation and variable resources at intermediate sizes on a logarithmic mass scale. Opposing selection is thought to occur in response to energetic constraints associated with predation and unpredictable resources. As body size approaches and exceeds the CBM, mammals face increasing risks of predation and daily energy requirements. Fast running speeds may require high BMRs, but unpredictable and low resources may select for low BMRs, which also reduce foraging time and distances and thus predation risks. If these two selection forces oppose each other persistently, minimum BMR variance may result. However, extreme BMR outliers at and close to the CBM should be indicative of unbalanced selection and predator avoidance alternatives (escapers vs. defenders), and may therefore provide indirect support for opposing selection. It was confirmed that body armor in defenders evolves at and above the CBM, and armored mammals had significantly lower BMRs than their nonarmored counterparts. However, analyses comparing the BMR of escapers--the fastest nonarmored runners (Lagomorpha)--with similar-sized counterparts were inconclusive and were confounded by limb morphology associated with speed optimization. These analyses suggest that the risks and costs of predation and the speed limitations of the plantigrade foot may constrain the evolution of large body sizes in plantigrade mammals.