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1.
Head circumference is used together with other measures as a proxy for central nervous system damage in the diagnosis of fetal alcohol spectrum disorders, yet the relationship between head circumference and brain volume has not been investigated in this population. The objective of this study is to characterize the relationship between head circumference, brain volume and cognitive performance in a large sample of children with prenatal alcohol exposure (n = 144) and healthy controls (n = 145), aged 5–19 years. All participants underwent magnetic resonance imaging to yield brain volumes and head circumference, normalized to control for age and sex. Mean head circumference, brain volume, and cognitive scores were significantly reduced in the prenatal alcohol exposure group relative to controls, albeit with considerable overlap between groups. Males with prenatal alcohol exposure had reductions in all three measures, whereas females with prenatal alcohol exposure had reduced brain volumes and cognitive scores, but no difference in head circumference relative to controls. Microcephaly (defined here as head circumference ≤ 3rd percentile) occurred more often in prenatal alcohol exposed participants than controls, but 90% of the exposed sample had head circumferences above this clinical cutoff indicating that head circumference is not a sensitive marker of prenatal alcohol exposure. Normalized head circumference and brain volume were positively correlated in both groups, and subjects with very low head circumference typically had below-average brain volumes. Conversely, over half of the subjects with very low brain volumes had normal head circumferences, which may stem from differential effects of alcohol on the skeletal and nervous systems. There were no significant correlations between head circumference and any cognitive score. These findings confirm group-level reductions in head circumference and increased rates of microcephaly in children with prenatal alcohol exposure, but raise concerns about the predictive value of this metric at an individual-subject level.  相似文献   

2.
24 families of probands with a high head circumference/height ratio greater than the 97th percentile were investigated for head circumference and height. It is concluded that "benign macrocephaly" represents rather the upper extreme of the normal distribution of head circumference than--as has been suggested by some authors--a discrete and autosomal dominant entity.  相似文献   

3.
Studies have shown that after controlling for the effects of body size on brain size, the brains of adult humans, rhesus monkeys, and chimpanzees differ in relative size, where males have a greater volume of cerebral tissue than females. We assess whether head circumference sexual dimorphism is present during early development by evaluating sex differences in relative head circumference in living fetuses and infants within the first year of life. Head circumference is used as a proxy for brain size in the fetus and infant. Femur length is used as a proxy for body length in the fetus. Ultrasonography was used to obtain fetal measures, and anthropometry was used to obtain postnatal measures in humans, rhesus monkeys, baboons, and common marmosets. We show that statistically significant but low levels of head circumference sexual dimorphism are present in humans, rhesus monkeys, and baboons in early life. On average, males have head circumferences about 2% larger than females of comparable femur/body length in humans, rhesus monkeys, and baboons. No evidence for head circumference sexual dimorphism in the common marmoset was found. Dimorphism was present across all body size ranges. We suggest that head circumference sexual dimorphism emerges largely postnatally and increases throughout maturation, particularly in humans who reach adult dimorphism values greater than the monkeys. We suggest that brain dimorphism is not likely to impose an additional energetic burden to the gestating or lactating mother. Finally, some of the problems with ascribing functional significance to brain size sexual dimorphism are discussed, and the energetic implications for brain size sexual dimorphism in infancy are assessed.  相似文献   

4.
A study of anthropometric variation and craniofacial growth in individuals with the Prader-Labhart-Willi syndrome (PLWS) illustrates the utility of anthropometry in clinical evaluation and research. Anthropometric measurements, including head length and breadth, minimum frontal diameter, and head circumference, were obtained on 38 PLWS individuals (21 with chromosome 15 deletions) with an age range from 2 weeks to 39 years. No anthropometric differences were found between the two chromosome subgroups. A relative deceleration in the growth of certain craniofacial dimensions (head circumference and length) is suggested by the negative correlations between age and Z-scores for the measurements. Raw values for minimum frontal diameter and head breadth were near or below the 5th percentile curve, while almost all values for head length and circumference fell within normal limits. The data support suggestions that dolichocephaly be considered an early diagnostic feature of PLWS. Furthermore, the status of narrow bifrontal diameter as a major feature of PLWS is confirmed.  相似文献   

5.
A relation between head circumference and brain weight of humans is generally believed to exist, but the literature contains only two studies which exhibit a quantitative aspect of the relation, showing that brain weight is proportional to the cube of the head circumference from birth through age 3.5 years. By assembling data from autopsy records, we have been able to show that this cubic relationship holds through brain maturation at around age 18 years.  相似文献   

6.
Historically, medical concerns about the deleterious effects of closely inbred marriages have focused on the risk posed by recessive Mendelian disease, with much less attention to developmental instability. We studied the effects of inbreeding (first‐cousin marriage) on growth and fluctuating asymmetry of 200 full‐term infants (101 inbred and 99 outbred) whose parents were of similar socioeconomic status in Sivas Province, Turkey. In addition to differences in their mean inbreeding coefficients (f = 1/16 for first cousins and f < 1/1,024 for unrelated parents), the consanguineous parents were less well educated (3 years, on average for both husbands and wives). We measured weight, height, head circumference, and chest circumference of the newborns, as well as four bilateral traits (ear width, ear length, and second and fourth digit lengths). After taking education into account, none of the measures of size (weight, height, head circumference, and chest circumference) and fluctuating asymmetry differed between the inbred and outbred groups. Male children of well‐educated parents, however, were larger and had less fluctuating asymmetry. Female children of well‐educated parents weighed more than those of less well‐educated parents, but were otherwise indistinguishable for height, head circumference, chest circumference, and fluctuating asymmetry. We conclude that inbreeding depression causes neither an increase in fluctuating asymmetry of full‐term newborns, nor a decrease in body size. Unmeasured variables correlated with education appear to have an effect on fluctuating asymmetry and size of male children and only a weak effect on size (weight) of female children. Am J Phys Anthropol 153:45–51, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   

7.
Microcephaly in familial holoprosencephaly   总被引:2,自引:0,他引:2  
The holoprosencephaly sequence (HS) is characterized by abnormalities in forebrain cleavage and midface development. Familial holoprosencephaly has been reported in several families and there appears to be variable expression of the disorder in those who inherit the gene. Previous investigators have suggested hypotelorism and/or missing central incisors as mild manifestations of autosomal dominant HS. We evaluated a large kindred with three individuals with severe brain anomalies and 12 individuals with minor manifestations of the disorder. The most consistent sign in those mildly affected was microcephaly. We suggest that head circumference is an important part of the evaluation of the relatives of a patient with holoprosencephaly.  相似文献   

8.
We report a child with nevoid basal-cell carcinoma syndrome (NBCCS) who showed an enlarged head circumference and cleft lip/cleft palate as sole signs of this syndrome at birth. Careful follow up and re-evaluation of this patient enabled us to diagnose the syndrome. Moreover, inspection of her father and sister indicated that they were also affected. An updated review of reported cases indicates that facial cleft occurs in approximately 5% of NBCCS patients. Various aspects of the disease and general measures for its monitoring and treatment are briefly discussed.  相似文献   

9.
We consider the effects of major prenatal economic shocks experienced by mothers on two indicators of newborn-infant health, birth weight and head circumference, using detailed microdata from the UK ALSPAC survey. Controlling for physiological and socioeconomic factors, an economic shock in the first 18 weeks of gestation lowers birth weight by 40–70 g and head circumference by 2–3 mm. We find evidence of transmission via poorer maternal health due to absolute material deprivation and tobacco and alcohol consumption, but not for the endocrinological effects of increased psychosocial anxiety. The fragile-male hypothesis holds for birth weight but not for head circumference, as predicted by recent theories on gender differences in prenatal development.  相似文献   

10.
Summary: The thymus is a central lymphatic organ reaching its largest size after the delivery. Its size is significantly affected by endogenous and exogenous negative factors. In our research, we investigated the relationship between the size of the thymus determined by sonography and anthropometric parameters as well as indexes demonstrating the nutritional status. The examined group consisted of 212 full-term newborns, all of which passed an anthropometric examination during the first five days after delivery (birth weight and length, mid-arm and head circumference). The following nutritional status indexes were calculated from estimated anthropometric dimensions: Quételet's index, Rohrer's index, birth weight-to-length ratio and mid-arm-to-head circumference ratio. The size of the thymus was assessed by sonography and expressed as the multiple of transversal width of the cranial thymus part and sagittal area of the major thymus lobe (so-called 'Thymic Index'). The Thymic Index showed a positive correlation with the majority of indicators of the newborn's nutritional status, but all of these correlations are low (Spearman correlation coefficients 0.228-0.409). The correlation of the size of thymus with the birth weight or birth weight-to-length ratio was stronger than the correlation with the Quételet's index or mid-arm circumference. The size of the thymus reflects the newborn's nutritional status assumed by anthropometry and can represent one of the "barometers of nutrition". Normal nutrition in the prenatal period plays a relatively critical role in the development of the immune system.  相似文献   

11.
目的:研究新疆伊犁哈萨克族成人身体围度的特征。方法:本次研究中针对新疆伊犁哈萨克族374例(男性192例,女性182例)成人的身体围度进行了测量以及做了相关的分析。对年龄组间围度值的变化进行方差分析,对年龄与围度之间的关系进行相关分析。并与我国其他26个族群的围度值进行聚类分析。结果:该区男性腰围、腹围年龄组间的差异具有统计学意义;该区女性除头围外的12项围度值在不同年龄组间差异均有统计学意义。女性围度值各年龄组间的差异比男性更加明显。直线相关分析,男性呼气围、腰围、腹围和臀围均与年龄呈正相关,女性颈围、躯干各部分围度和上肢围度均与年龄呈正相关。新疆伊犁哈萨克族在26个族群中头围、胸围、腹围、臀围、大腿围和小腿围6项围度值均处于较高水平。聚类分析显示,哈萨克族围度值与乌孜别克族最接近,我国20个人群围度比较,表明哈萨克族族围度值较大。结论:伊犁哈萨克族身体围度值较大,具有东亚类型族群的围度特征。  相似文献   

12.
The study of consanguineous marriage is an efficient way to elucidate the genetic structure of human populations. Such matings give an opportunity for recessive genes to manifest themselves by becoming homozygous. The present attempt examines the effects of parental consanguinity on various anthropometric measurements among the Sheikh Sunni Muslim boys of old Delhi between the ages of 11 and 16 years. A slight inbreeding depression has been observed for all eight anthropometric measurements, i.e., stature, span, sitting height, head length, head circumference, chest girth, and calf circumference. The results support earlier studies in regard to the effect of consanguinity on anthropometric measurements.  相似文献   

13.
One hundred fifty-nine purebred Guzerat (8 to 110 months of age) and sixty Nellore bulls (8-30 months of age) were used in two trials to examine testicular development and consistency, body weight changes, puberty and semen traits. Scrotal circumference measurements and semen collections by electroejaculation were made every 28 d. At both trial locations, bulls were maintained under grazing conditions and fed commercial protein supplements (2 kg/head/day) during the dry season. Age and body weight affected (P<0.01) scrotal circumference in both breeds. Scrotal circumference increased (P<0.01) linearly with age and body weight. However, scrotal circumference tended to reach mature size more rapidly than did body weight in both Guzerat and Nellore bulls. Correlation coefficients between scrotal circumference and semen traits were positive (P<0.01) ranging from 0.49 to 0.73 in the two breeds, but were not significant for testicular consistency in either breed. Scrotal circumference and age at puberty of Guzerat and Nellore bulls averaged 25.6 +/- 2.2 cm at 18.0 +/- 2.0 mo and 23.6 +/- 0.2 cm at 18.5 +/- 2.7 mo, respectively. Nellore bulls were 42 kg lighter than Guzerat at puberty. Testicular consistency was not affected by either age of body weight (P>0.10) in these young bulls. The percentages of abnormal spermatozoa were higher (P<0.01) at 13 to 15 mo of age in Guzerat (11.1%) and Nellore (14.4%) bulls than at 22 to 24 mo (6.7 and 8.0%, respectively). These data indicate that scrotal circumference measurements can be a useful tool for selecting and improving semen traits of young Guzerat and Nellore bulls under tropical grazing conditions.  相似文献   

14.
In the 1997-1998 and 1998-1999 school years we measured head dimensions of 1600 boys from 6 to 13 years attending elementary and middle schools in towns of the Cagliari area (Sardinia, Italy). For each age, we compared the mean values for circumference, length and width of the head with Canadian standards, widely used by Sardinian pediatricians. The t-test shows that the means of the three variables are significantly lower in the Cagliari boys than in their Canadian contemporaries, with the exception of head circumference in 6 and 7 year-olds, and of head width in 10 year-olds. Therefore, it is necessary to produce specific growth charts for circumference, length and width of the head of Sardinian children rather than evaluate their growth using standards of populations with different ethnic, geographical and socio-economic backgrounds.  相似文献   

15.
Head measurements are performed within the anthropological investigations of school children from Jena (Germany) since more than 5 decades (1944-1995). Here we report on secular changes of the head length, the head breadth and the cephalic index. The head circumference, measured in 1985 and in 1995, is included in the analysis. Head length and head breadth show a contrary development over the whole period: the average length of the head increases between the consecutive investigations, whereas the breadth of the head decreases continuously between the separate investigations. As a consequence the cephalic index decreases in boys and girls for about 8 units since 1944. In this way a secular change of the shape of the head in the sense of debrachycephalisation can be proved in Jena school children. The head circumference, however, remains nearly constant between 1985 and 1995. Possible causes of this process of debrachycephalisation are focussed in this article.  相似文献   

16.
Body sizes at birth are important clinical indicators widely used for evaluation of prenatal growth. Japan had significant socioeconomic improvement around the 1960s, and these environmental changes may influence physiologically prenatal growth. Furthermore, in Japan, measurements of size at birth for birth certificates are weight and height. Thus, we can refer to annual data on weight and height, but not on head and chest circumference at birth. In this study we measured the weight, height, and head and chest circumference at birth among 6,563 Japanese singleton healthy infants, annually in 1962 and 1988, and examined secular trends of these anthropometric measurements. The boys consistently exceeded the girls in all four variables. Birth weight and height increased significantly from the 1960s to '70s, but did not differ between the '70s and '80s in both boys and girls. Secular trends of head and chest circumference were different from them. In both boys and girls, head and chest circumference increased significantly from the '60s to the '70s, but decreased significantly from the '70s to the '80s. No difference of head circumference during the '60s and '80s was found, but the difference of chest circumference was found. Size at birth was likely to increase from the '60s to '70s in Japan. These findings suggest that the environmental changes such as socioeconomic improvements influence the prenatal growth.  相似文献   

17.
We test the hypothesis that polymorphisms of the brain regulator genes MCPH1 and ASPM contribute to variations in human brain size and its correlates. We measured general mental ability, head circumference and social intelligence in 644 Canadian adults (496 Caucasians, 36 Orientals, 84 Mixed Race/Other and 28 Blacks; 257 men and 387 women). The gene polymorphisms were assessed from buccal DNA; mental ability by Wonderlic Personnel Test and Multidimensional Aptitude Battery; head circumference by stretchless tape; and social intelligence by prosocial attitude questionnaires. Although all measures were construct valid and the allele frequencies showed expected population differences, no relationship was found between the genes and any of the criteria. Among Caucasian 18-25 year olds, for example, the two mental ability tests correlated with each other (r=0.78, N=476, p<0.001), with head circumference (r=0.17, N=182, p<0.05) and with prosocial attitudes (r=0.23, N=182, p<0.001).  相似文献   

18.
BACKGROUND: The mutation of the IRS-1 gene is one of the genetic risk factors which, it is speculated, is associated with insulin resistance or predisposition to type 2 diabetes. The aim of our study was to evaluate the association between the Gly972Arg polymorphism in the IRS-1 gene and birth weight in newborn children with adequate gestational age. MATERIAL AND METHODS: 100 newborn children with adequate gestational age (38-42 weeks), whose mother had no disorders during pregnancy, were studied. Genomic DNA was extracted from umbilical cord blood leukocytes, and Gly972Arg polymorphism in the IRS-1 gene was genotyped using the PCR-based method. RESULTS: Birth weight was significantly lower in the newborn with the IRS-1 Gly972Arg polymorphism compared with a control group (3161.75 +/- 380.86 g vs. 3427.92 +/- 468.86 g). Body length and head circumference at birth were also lower in the neonates with that polymorphism (54.38 +/- 3.13 cm vs. 52.69 +/- 2.91 cm, and 34.08 +/- 1.47 vs. 33.63 +/- 0.81, respectively). CONCLUSIONS: The results suggest that the Gly972Arg genotype is associated with lower birth weight, body length and head circumference in neonates with adequate gestational age.  相似文献   

19.
The feeds of 14 very low birthweight infants (birth weight less than 1500 g) were supplemented with a glucose polymer (Caloreen) at the rate of 6 g/kg body weight daily. Seven day periods of supplementation were alternated with seven day periods of normal feeding. Adding the glucose polymer significantly increased the rate of weight gain in these infants from 105 g/week to 140 g/week; growth rates in terms of length and head circumference were not affected. No adverse effects were noted. Glucose polymer is a useful energy supplement for very low birthweight infants.  相似文献   

20.
2009~2013年在中国22个省、自治区测量了26695例(乡村男性8174例,城市男性4791例,乡村女性8327例,城市女性5403例)的头围、颈围、平静胸围、吸气时胸围、呼气时胸围、腹围、臀围、大腿围、小腿围、上臂围、前臂围、上臂最大围值,进行了围度与纬度、经度、年龄的相关分析,城市与乡村汉族、北方与南方汉族身体围度均数的比较。结果发现,男性的上臂围、上臂最大围与纬度无显著相关,其余10项围度均与纬度呈显著正相关。女性12项围度均与纬度呈显著正相关。男性、女性12项围度均与经度呈显著正相关,男性四肢围度多与年龄呈显著负相关。女性下肢围度也与年龄呈显著负相关,但上肢3项围度与年龄呈显著正相关。男性、女性躯干5项围度、颈围随年龄增加而增大。北方男性除头围、上臂围值与南方男性接近外,其余10项围度值均大于南方男性。北方女性12项围度值均大于南方女性。城市、乡村汉族12项围度的差异均具有统计学意义。城市汉族的各项围度均大于乡村汉族。  相似文献   

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