Growth pattern from birth to adulthood in African pygmies of known age.
Ontology highlight
ABSTRACT:
SUBMITTER: Rozzi FV
PROVIDER: S-EPMC4525207 | biostudies-literature | 2015 Jul
REPOSITORIES: biostudies-literature
Publications
Growth pattern from birth to adulthood in African pygmies of known age.
Rozzi Fernando V Ramirez FV Koudou Yves Y Froment Alain A Le Bouc Yves Y Botton Jérémie J
Nature communications 20150728
The African pygmy phenotype stems from genetic foundations and is considered to be the product of a disturbance in the growth hormone-insulin-like growth factor (GH-IGF) axis. However, when and how the pygmy phenotype is acquired during growth remains unknown. Here we describe growth patterns in Baka pygmies based on two longitudinal studies of individuals of known age, from the time of birth to the age of 25 years. Body size at birth among the Baka is within standard limits, but their growth ra ...[more]
Similar Datasets
Project description:Although dissimilarities in cranial and post-cranial morphology among African pygmies groups have been recognized, comparative studies on skull morphology usually pull all pygmies together assuming that morphological characters are similar among them and different with respect to other populations. The main aim of this study is to compare cranial morphology between African pygmies and non-pygmies populations from Equatorial Africa derived from both the Eastern and the Western regions in order to test if the greatest morphological difference is obtained in the comparison between pygmies and non-pygmies. Thirty three-dimensional (3D) landmarks registered with Microscribe in four cranial samples (Western and Eastern pygmies and non-pygmies) were obtained. Multivariate analysis (generalized Procrustes analysis, Mahalanobis distances, multivariate regression) and complementary dimensions of size were evaluated with ANOVA and post hoc LSD. Results suggest that important cranial shape differentiation does occur between pygmies and non-pygmies but also between Eastern and Western populations and that size changes and allometries do not affect similarly Eastern and Western pygmies. Therefore, our findings raise serious doubt about the fact to consider African pygmies as a homogenous group in studies on skull morphology. Differences in cranial morphology among pygmies would suggest differentiation after divergence. Although not directly related to skull differentiation, the diversity among pygmies would probably suggest that the process responsible for reduced stature occurred after the split of the ancestors of modern Eastern and Western pygmies.
| S-EPMC2964320 | biostudies-literature
Project description:There is growing evidence that early growth influences bone mass in later life but most studies are limited to birth weight and/or early infant growth and dual-energy X-ray absorptiometry (DXA) measurements. In a British birth cohort study with prospective measures of lifetime height and weight, we investigated the growth trajectory in relation to bone in males (M) and females (F) at 60 to 64 years old. Outcomes were DXA measures of hip and spine areal bone density (aBMD) (n?=?1658) and pQCT measures of distal and diaphyseal radius cross-sectional area (CSA), strength, and volumetric bone density (vBMD) (n?=?1350 of the 1658). Regression models examined percentage change in bone parameters with standardized measures of birth weight, height, and weight. A series of conditional growth models were fitted for height and weight gain (using intervals: birth-2, 2-4, 4-7, 7-15, 15-20, 20-36, and 36-64 years) and height gain (using intervals: 2-4, 4-7, 7-15, and 15-36 years). Birth weight was positively related to bone CSA (M: 1.4%; 95% confidence interval [CI], 0.3%-2.5%; F: 1.3%; 95% CI, 0.3%-2.4% per 1 SD increase in birth weight for diaphyseal CSA) and strength (M: 1.8%; 95% CI, 0.3-3.4; F: 2.0%; 95% CI, 0.5-3.5). No positive associations were found with trabecular, total, or cortical vBMD. One SD change in prepubertal and postpubertal height and weight velocities were associated with between 2% and 5% greater bone CSA and strength. Height gain in later years was negatively associated with trabecular vBMD. Weight gain velocity during the adult years was positively associated with up to 4% greater trabecular and total BMD, and 4% greater aBMD at hip and spine. In a cohort born in the early post-war period, higher birth weight, gaining weight and height faster than others, particularly through the prepubertal and postpubertal periods, was positively related to bone strength, mostly through greater bone CSA, at 60 to 64 years.
| S-EPMC4292430 | biostudies-literature
Project description:Sociocultural phenomena, such as exogamy or phylopatry, can largely determine human sex-specific demography. In Central Africa, diverging patterns of sex-specific genetic variation have been observed between mobile hunter-gatherer Pygmies and sedentary agricultural non-Pygmies. However, their sex-specific demography remains largely unknown. Using population genetics and approximate Bayesian computation approaches, we inferred male and female effective population sizes, sex-specific migration, and admixture rates in 23 Central African Pygmy and non-Pygmy populations, genotyped for autosomal, X-linked, Y-linked, and mitochondrial markers. We found much larger effective population sizes and migration rates among non-Pygmy populations than among Pygmies, in agreement with the recent expansions and migrations of non-Pygmies and, conversely, the isolation and stationary demography of Pygmy groups. We found larger effective sizes and migration rates for males than for females for Pygmies, and vice versa for non-Pygmies. Thus, although most Pygmy populations have patrilocal customs, their sex-specific genetic patterns resemble those of matrilocal populations. In fact, our results are consistent with a lower prevalence of polygyny and patrilocality in Pygmies compared with non-Pygmies and a potential female transmission of reproductive success in Pygmies. Finally, Pygmy populations showed variable admixture levels with the non-Pygmies, with often much larger introgression from male than from female lineages. Social discrimination against Pygmies triggering complex movements of spouses in intermarriages can explain these male-biased admixture patterns in a patrilocal context. We show how gender-related sociocultural phenomena can determine highly variable sex-specific demography among populations, and how population genetic approaches contrasting chromosomal types allow inferring detailed human sex-specific demographic history.
| S-EPMC3603314 | biostudies-literature
Project description:Pygmy populations occupy a vast territory extending west-to-east along the central African belt from the Congo Basin to Lake Victoria. However, their numbers and actual distribution is not known precisely. Here, we undertake this task by using locational data and population sizes for an unprecedented number of known Pygmy camps and settlements (n = 654) in five of the nine countries where currently distributed. With these data we develop spatial distribution models based on the favourability function, which distinguish areas with favourable environmental conditions from those less suitable for Pygmy presence. Highly favourable areas were significantly explained by presence of tropical forests, and by lower human pressure variables. For documented Pygmy settlements, we use the relationship between observed population sizes and predicted favourability values to estimate the total Pygmy population throughout Central Africa. We estimate that around 920,000 Pygmies (over 60% in DRC) is possible within favourable forest areas in Central Africa. We argue that fragmentation of the existing Pygmy populations, alongside pressure from extractive industries and sometimes conflict with conservation areas, endanger their future. There is an urgent need to inform policies that can mitigate against future external threats to these indigenous peoples' culture and lifestyles.
| S-EPMC4711706 | biostudies-literature
Project description:BackgroundRapid weight gain in childhood may increase the risk of chronic adult diseases. Few studies have examined the effects of lifecourse weight gain on waist circumference (WC), hip circumference (HC), or waist-to-hip ratio (WHR).ObjectiveTo evaluate the effects of birthweight and weight gain from birth to age 23 years on WC, HC, and WHR in young adults.DesignPopulation-based birth cohort study started in 1982. A sample of 856 individuals was examined in 2006. Conditional growth analyses were carried out with adjustment for confounders. WC and HC were also mutually adjusted.ResultsWeight gains during all age ranges studied (birthweight, 0-2, 2-4, 4-15, 15-18/19, and 18/19-23 years) were positively associated with WC and HC in both sexes. These effects were strongest from 4 to 15 years range (beta = 5.0 cm for both circumferences). Proxies for visceral adipose tissue (WHR and WC adjusted for HC) were associated with weight gain after 2 years in females and after 4 years in males. Subcutaneous adipose and muscular tissues, assessed by HC adjusted for WC, were associated with birthweight and weight gain from 0 to 2 years in both sexes, and again with weight gains from 4 to 18 years in males and 4 to 15 years in females.ConclusionsWeight gains in utero and in the first 2 years had long-term effects on HC, but weight gain after age 4 years was strongly associated with WC. Weight gains up to age 2 years may reduce cardiovascular risk associated with adult fat patterns in a middle-income setting.
| S-EPMC3448044 | biostudies-literature
Project description:BACKGROUND: Pandemic community-acquired methicillin-resistant Staphylococcus aureus isolates (CA-MRSA) predominantly encode the Panton-Valentine leukocidin (PVL), which can be associated with severe infections. Reports from non-indigenous Sub-Saharan African populations revealed a high prevalence of PVL-positive isolates. The objective of our study was to investigate the S. aureus carriage among a remote indigenous African population and to determine the molecular characteristics of the isolates, particularly those that were PVL-positive. METHODOLOGY/PRINCIPAL FINDINGS: Nasal S. aureus carriage and risk factors of colonization were systematically assessed in remote Gabonese Babongo Pygmies. Susceptibility to antibiotics, possession of toxin-encoding genes (i.e., PVL, enterotoxins, and exfoliative toxins), S. aureus protein A (spa) types and multi-locus sequence types (MLST) were determined for each isolate. The carriage rate was 33%. No MRSA was detected, 61.8% of the isolates were susceptible to penicillin. Genes encoding PVL (55.9%), enterotoxin B (20.6%), exfoliative toxin D (11.7%) and the epidermal cell differentiation inhibitor B (11.7%) were highly prevalent. Thirteen spa types were detected and were associated with 10 STs predominated by ST15, ST30, ST72, ST80, and ST88. CONCLUSIONS: The high prevalence of PVL-positive isolates among Babongo Pygmies demands our attention as PVL can be associated with necrotinzing infection and may increase the risk of severe infections in remote Pygmy populations. Many S. aureus isolates from Babongo Pygmies and pandemic CA-MRSA-clones have a common genetic background. Surveillance is needed to control the development of resistance to antibiotic drugs and to assess the impact of the high prevalence of PVL in indigenous populations.
| S-EPMC3091839 | biostudies-literature
Project description:BackgroundPreterm birth has been associated with increased risk of venous thromboembolism (VTE) in infancy, but the longer-term risk is unknown. Our aim was to examine this association from birth through young adulthood.MethodsNational cohort study of 3,571,574 individuals who were live-born in Sweden from 1973 through 2008, including 206,844 born preterm (gestational age <37 weeks), and followed up to 2010 (ages 0-38 years). The main outcome was VTE.ResultsA total of 7519 (0.2%) individuals were diagnosed with VTE in 70.8 million person-years of follow-up. Low gestational age at birth was associated with VTE in infancy (ages <1 year: adjusted hazard ratio 47.16 [95% confidence interval 21.30-104.42] for 22 to 27 weeks, 5.54 [2.53-12.12] for 28 to 33 weeks, 3.54 [2.07-6.06] for 34 to 36 weeks, 1.00 for 37 to 41 weeks [reference]), early childhood (ages 1-5 years), and young adulthood (ages 18-38 years: adjusted hazard ratio 2.76 [1.43-5.31] for 22 to 27 weeks, 1.53 [1.24-1.89] for 28 to 33 weeks, 1.24 [1.10-1.40] for 34 to 36 weeks, and 1.00 for 37 to 41 weeks [reference]), but not in late childhood (ages 6-12 years). Very preterm (<34 weeks) but not late preterm birth (34-36 weeks) was also associated with VTE in adolescence (ages 13-17 years). After further adjustment for comorbidities, these associations were attenuated, but most remained significantly elevated.ConclusionsIn this large national cohort, low gestational age at birth was associated with increased risk of VTE in infancy, early childhood, and young adulthood.
| S-EPMC10556725 | biostudies-literature
Project description:ObjectiveTo investigate growth trajectories from age 2.5 to 19 years in individuals born before 26 weeks of gestation (extremely preterm; EP) compared with term-born controls.MethodsMultilevel modelling of growth data from the EPICure study, a prospective 1995 birth cohort of 315 EP participants born in the UK and Ireland and 160 term-born controls recruited at school age. Height, weight, head circumference and body mass index (BMI) z-scores were derived from UK standards at ages 2.5, 6, 11 and 19 years.Results129 (42%) EP children were assessed at 19 years. EP individuals were on average 4.0 cm shorter and 6.8 kg lighter with a 1.5 cm smaller head circumference relative to controls at 19 years. Relative to controls, EP participants grew faster in weight by 0.06 SD per year (95% CI 0.05 to 0.07), in head circumference by 0.04 SD (95% CI 0.03 to 0.05), but with no catch-up in height. For the EP group, because of weight catch-up between 6 and 19 years, BMI was significantly elevated at 19 years to +0.32 SD; 23.4% had BMI >25 kg/m2 and 6.3% >30 kg/m2 but these proportions were similar to those in control subjects. EP and control participants showed similar pubertal development in early adolescence, which was not associated with height at 19 years in either study group. Growth through childhood was related to birth characteristics and to neonatal feeding practices.ConclusionsEP participants remained shorter and lighter and had smaller head circumferences than reference data or controls in adulthood but had elevated BMI.
| S-EPMC7115967 | biostudies-literature
Project description:ObjectivesFaster growth after preterm birth benefits long-term cognitive functioning. Whether these benefits extend to mental health remains largely unknown. We examined if faster growth in infancy is associated with better self-reported mental health in young adults born preterm at very low birth weight (VLBW) (< 1500 g).Study designAs young adults, participants of the Helsinki Study of Very Low Birth Weight Adults self-reported symptoms of depression and attention deficit/hyperactivity disorder (ADHD) (n = 157) and other psychiatric problems (n = 104). As main predictors of mental health outcomes in linear regression models, we used infant weight, length, and head circumference at birth, term, and 12 months of corrected age, and growth between these time points. Growth data were collected from records and measures at term and at 12 months of corrected age were interpolated. Additionally, we examined the moderating effects of intrauterine growth restriction.ResultsSize at birth, term, or 12 months of corrected age, or growth between these time points were not associated with mental health outcomes (p-values >0.05). Intrauterine growth restriction did not systematically moderate any associations.ConclusionsDespite the high variability in early growth of VLBW infants, the previously described association between slow growth in infancy and poorer cognitive functioning in later life is not reflected in symptoms of depression, ADHD, and other psychiatric problems. This suggests that the development of cognitive and psychiatric problems may have dissimilar critical periods in VLBW infants.
| S-EPMC4556664 | biostudies-literature
Project description:OBJECTIVES: To investigate the early determinants of overweight and obesity status at age two years. METHODS: A total of 1098 healthy neonates (563 boys and 535 girls) were involved in this community-based prospective study in China. Data on body weight and length were collected at birth, the 3(rd) and 24(th) month. A self-administered questionnaire was used to collect data on social demography and feeding patterns of children, etc. Three multivariable logistic regression models were employed to make various comparisons of weight status, i.e., model 1 (obesity vs. non-obesity), model 2 (combined overweight and obesity vs. normal weight, and model 3 (obesity, overweight and normal weight). RESULTS: Prevalences of overweight/obesity (95(th) >BMI ≥85(th) p and BMI ≥95(th) p, referring to WHO BMI standards) at 2 years of age are 15.8%/11.2% for boys and 12.9%/9.0% for girls, respectively. Being born with macrosomia (OR: 1.80-1.88), relatively greater BMI increment in the first 3 months (OR: 1.15-1.16) and bottle emptying by encouragement at age two (OR: 1.30-1.57) were found in all three models to be significant risk factors for higher BMI status at 2 years. Pre-pregnancy maternal BMI (OR: 1.09-1.12), paternal BMI (OR: 1.06), and mixed breastfeeding (OR: 1.54-1.57) or formula feeding (OR: 1.90-1.93) in the first month were identified as significant in models 2 and 3. Child-initiated bottle emptying at age two was observed to increase the risk of obesity by 1.31 times but only in model 1. CONCLUSION: Fetal and early postnatal growth and feeding pattern appear to have significant impacts on early childhood overweight and obesity status independent of parental BMI. Policy-based and multidisciplinary approaches to promote breastfeeding and enhancement of feeding skills of care takers may be promising intervention strategies.
| S-EPMC3673988 | biostudies-other