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Social transmission of information is taxonomically widespread and could have profound effects on the ecological and evolutionary dynamics of animal communities. Demonstrating this in the wild, however, has been challenging. Here we show by field experiment that social transmission among predators can shape how selection acts on prey defences. Using artificial prey and a novel approach in statistical analyses of social networks, we find that blue tit (Cyanistes caeruleus) and great tit (Parus major) predators learn about prey defences by watching others. This shifts population preferences rapidly to match changes in prey profitability, and reduces predation pressure from naïve predators. Our results may help resolve how costly prey defences are maintained despite influxes of naïve juvenile predators, and suggest that accounting for social transmission is essential if we are to understand coevolutionary processes.

Considerable progress has been made in understanding the neurobehavioral effects of nociceptin peptide (N/OFQ) and its NOP receptor. Recent interest has focused on its role in stress and cognition, with consideration of therapeutic potential in regard to anxiety and mood disorders. Research has interrogated the mechanisms of action of N/OFQ peptide in the context of stress-related behavior. We are interested in the endogenous role of N/OFQ and NOP receptor in terms of adaptation to chronic stress. Our research has highlighted the importance of associated limbic regions including the bed nucleus, extended amygdala, in addition to thalamic reticular nucleus as important sites for long-term adaptations in endogenous N/OFQ function in chronic stress. Such research raises interest in appreciation of extended limbic connections and novel pathways which allow us to reevaluate current understanding of stress neurocircuitry. Examination of endogenous N/OFQ-NOP receptor modulation of monoaminergic and amino acid transmitter systems in this extended limbic architecture will facilitate deeper understanding of the tonic control of behavior. Application of in vivo experimental approaches to models of abnormal neurodevelopment and heightened stress vulnerability in adulthood will enable the role of N/OFQ in complex neuropsychiatric disorders including schizophrenia and post-traumatic stress disorder to be defined., (© 2019 Elsevier Inc. All rights reserved.)

Background: Malnourished children show variable growth responses to nutritional rehabilitation. We aimed to investigate whether these differences could be explained by variations in growth and energy-regulating hormones., Methods: Quasi-experimental study: Children aged 6-24 months in rural Gambia were recruited to controls if weight-for-height z-score (WHZ) > -2 (n = 22), moderate acute malnutrition if WHZ < -2 and > -3 (n = 18) or severe acute malnutrition if WHZ < -3 (n = 20). Plasma hormone and salivary CRP levels were determined by ELISA., Results: In univariable analyses, increases in weight-for-age z-score (WAZ) in malnourished children were positively correlated with insulin (F-ratio 7.8, p = 0.006), C-peptide (F-ratio 12.2, p < 0.001) and cortisol (F-ratio 5.0, p = 0.03). In multivariable analysis, only baseline C-peptide (F-ratio 7.6, p = 0.009) predicted the changes in WAZ over 28 days of interventions., Conclusion: In rural Gambian, malnourished children, although it cannot be used in isolation, baseline C-peptide was a predictor of future response to rehabilitation.

[This corrects the article on p. 219 in vol. 8, PMID: 28912754.].

Background: Severe wasting affects 16 million under 5's and carries an immediate risk of death. Prevalence remains unacceptably high in sub-Saharan Africa and early infancy is a high-risk period. We aimed to explore risk factors for severe wasting in rural Gambian infants., Methods: We undertook a case-control study from November 2014 to June 2015, in rural Gambia. Cases had WHO standard weight-for-length z-scores (WLZ) < -3 on at least 1 occasion in infancy. Controls with a WLZ > -3 in the same interval, matched on age, gender, village size and distance from the clinic were selected. Standard questionnaires were used to assess maternal socioeconomic status, water sanitation and hygiene and maternal mental health. Conditional logistic regression using a multivariable model was used to determine the risk factors for severe wasting. Qualitative in depth interviews were conducted with mothers and fathers who were purposively sampled. A thematic framework was used to analyse the in-depth interviews., Results: Two hundred and eighty (77 cases and 203 controls) children were recruited. In-depth interviews were conducted with 16 mothers, 3 fathers and 4 research staff members. The mean age of introduction of complementary feeds was similar between cases and controls (5.2 [SD 1.2] vs 5.1 [SD 1.3] months). Increased odds of severe wasting were associated with increased frequency of complementary feeds (range 1-8) [adjusted OR 2.06 (95%: 1.17-3.62), p = 0.01]. Maternal adherence to the recommended infant care practices was influenced by her social support networks, most importantly her husband, by infant feeding difficulties and maternal psychosocial stressors that include death of a child or spouse, recurrent ill health of child and lack of autonomy in child spacing., Conclusion: In rural Gambia, inappropriate infant feeding practices were associated with severe wasting in infants. Additionally, adverse psychosocial circumstances and infant feeding difficulties constrain mothers from practising the recommended child care practices. Interventions that promote maternal resilience through gender empowerment, prioritising maternal psychosocial support and encouraging the involvement of fathers in infant and child care promotion strategies, would help prevent severe wasting in these infants.

Vitamin D binding protein (DBP) concentration is known to influence the availability and bioactivity of vitamin D metabolites but its diurnal rhythm (DR), its inter-relationships with the DRs of vitamin D metabolites and its influence on free vitamin D metabolite concentrations are not well described. The DRs of plasma total 25(OH)D, total 1,25(OH) 2 D, DBP, albumin and calculated free 25(OH)D and free 1,25(OH) 2 D were measured in men and women aged 60-75 years and resident in the UK (n 30), Gambia (n 31) and China (n 30) with differences in lifestyle, dietary intake and vitamin D status. Blood samples were collected every 4h for 24h and DRs statistically analysed with Fourier regression. Gambians had significantly higher plasma concentrations of vitamin D metabolites and lower albumin concentration compared to the British and Chinese. Significant DRs were observed for all analytes and calculated free vitamin D metabolites (P<0.01). The pattern of DRs was similar between countries. The magnitude of the DRs of free 1,25(OH) 2 D was attenuated compared to that of total 1,25(OH) 2 D whereas it was not different between total and free 25(OH)D. Relationships between the DRs were generally weak. There was no phase shift between 1,25(OH) 2 D and DBP with the strongest cross correlation at 0h time lag (r=0.15, P=<0.001). In comparison, 25(OH)D correlated less well with DBP (1h time lag, r=0.07, P=0.12). These data demonstrate a relationship between the DRs of 1,25(OH) 2 D and DBP, possibly to maintain free 1,25(OH) 2 D concentrations. In contrast, the DRs of total and free 25(OH)D appeared to be less influenced by DBP, suggesting that DBP has comparatively less effect on 25(OH)D concentration and 25(OH)D availability. This work highlights the importance of standardisation in timing of sample collection particularly for the assessment of plasma protein concentrations., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The Gambian Bone and Muscle Ageing Study is a prospective observational study investigating bone and muscle ageing in men and women from a poor, subsistence farming community of The Gambia, West Africa. Musculoskeletal diseases, including osteoporosis and sarcopenia, form a major part of the current global non-communicable disease burden. By 2050, the vast majority of the world's ageing population will live in low- and middle-income countries with an estimated two-fold rise in osteoporotic fracture. The study design was to characterise change in bone and muscle outcomes and to identify possible preventative strategies for fracture and sarcopenia in the increasing ageing population. Men and women aged ≥40 years from the Kiang West region of The Gambia were recruited with stratified sampling by sex and age. Baseline measurements were completed in 488 participants in 2012 who were randomly assigned to follow-up between 1.5 and 2 years later. Follow-up measurements were performed on 465 participants approximately 1.7 years after baseline measurements. The data set comprises a wide range of measurements on bone, muscle strength, anthropometry, biochemistry, and dietary intake. Questionnaires were used to obtain information on health, lifestyle, musculoskeletal pain, and reproductive status. Baseline cross-sectional data show preliminary evidence for bone mineral density and muscle loss with age. Men had greater negative differences in total body lean mass with age than women following adjustments for body size. From peripheral quantitative computed tomography scans, greater negative associations between bone outcomes and age at the radius and tibia were shown in women than in men. Ultimately, the findings from The Gambian Bone and Muscle Ageing Study will contribute to the understanding of musculoskeletal health in a transitioning population and better characterise fracture and sarcopenia incidence in The Gambia with an aim to the development of preventative strategies against both.

Background: Multiple micronutrients (MMN) are commonly prescribed in pediatric primary healthcare in sub-Saharan Africa to improve nutritional status and appetite without evidence for their effectiveness or international clinical guidelines. Community-wide MMN supplementation has shown limited and heterogeneous impact on growth and morbidity. Short-term ready-to-use therapeutic foods in acutely sick children in a hospital setting also had limited efficacy regarding subsequent growth. The effectiveness of MMN in improving morbidity or growth in sick children presenting for primary care has not been assessed., Methods and Findings: We undertook a double-blind randomised controlled trial of small-quantity lipid-based nutrient supplements (SQ-LNS) fortified with 23 micronutrients in children aged 6 months (mo) to 5 years (y) presenting with an illness at a rural primary healthcare centre in The Gambia. Primary outcomes were repeat clinic presentations and growth over 24 wk. Participants were randomly assigned to receive 1 of 3 interventions: (1) supplementation with micronutrient-fortified SQ-LNS for 12 wk (MMN-12), (2) supplementation with micronutrient-fortified SQ-LNS for 6 wk followed by unfortified SQ-LNS for 6 wk (MMN-6), or (3) supplementation with unfortified SQ-LNS for 12 wk (MMN-0) to be consumed in daily portions. Treatment masking used 16 letters per 6-wk block in the randomisation process. Blinded intention-to-treat analysis based on a prespecified statistical analysis plan included all participants eligible and correctly enrolled. Between December 2009 and June 2011, 1,101 children (age 6-60 mo, mean 25.5 mo) were enrolled, and 1,085 were assessed (MMN-0 = 361, MMN-6 = 362, MMN-12 = 362). MMN supplementation was associated with a small increase in height-for-age z-scores 24 wk after recruitment (effect size for MMN groups combined: 0.084 SD/24 wk, 95% CI: 0.005, 0.168; p = 0.037; equivalent to 2-5 mm depending on age). No significant difference in frequency of morbidity measured by the number of visits to the clinic within 24 wk follow-up was detected with 0.09 presentations per wk for all groups (MMN-0 versus MMN-6: adjusted incidence rate ratio [IRR] 1.03, 95% CI: 0.92, 1.16; MMN-0 versus MMN-12: 1.05, 95% CI: 0.93, 1.18). In post hoc analysis, clinic visits significantly increased by 43% over the first 3 wk of fortified versus unfortified SQ-LNS (adjusted IRR 1.43; 95% CI: 1.07, 1.92; p = 0.016), with respiratory presentations increasing by 52% with fortified SQ-LNS (adjusted IRR 1.52; 95% CI: 1.01, 2.30; p = 0.046). The number of severe adverse events during supplementation were similar between groups (MMN-0 = 20 [1 death]; MMN-6 = 21 [1 death]; MMN-12 = 20 [0 death]). No participant withdrew due to adverse effects. Study limitations included the lack of supervision of daily supplementation., Conclusion: Prescribing micronutrient-fortified SQ-LNS to ill children presenting for primary care in rural Gambia had a very small effect on linear growth and did not reduce morbidity compared to unfortified SQ-LNS. An early increase in repeat visits indicates a need for the establishment of evidence-based guidelines and caution with systematic prescribing of MMN. Future research should be directed at understanding the mechanisms behind the lack of effect of MMN supplementation on morbidity measures and limited effect on growth., Trial Registration: ISRCTN 73571031.

Background: Growth faltering remains common in children in sub-Saharan Africa and is associated with substantial morbidity and mortality. Due to a very slow decline in the prevalence of stunting, the total number of children with stunting continues to rise in sub-Saharan Africa. Identification of effective interventions remains a challenge., Methods: We analysed the effect of 36 years of intensive health interventions on growth in infants and young children from three rural Gambian villages. Routine growth data from birth to age 2 years were available for 3659 children between 1976 and 2012. Z scores for weight-for-age, length-for-age, weight-for-length, mid-upper-arm circumference, and head circumference were calculated using the WHO 2006 growth standards. Seasonal patterns of mean Z scores were obtained by Fourier regression. We additionally defined growth faltering as fall in Z score between 3 months and 21 months of age., Findings: We noted secular improvements in all postnatal growth parameters (except weight-for-length), accompanied by declines over time in seasonal variability. The proportion of children with underweight or stunting at 2 years of age halved during four decades of the study period, from 38·7% (95% CI 33·5-44·0) for underweight and 57·1% (51·9-62·4) for stunting. However, despite unprecedented levels of intervention, postnatal growth faltering persisted, leading to poor nutritional status at 24 months (length-for-age Z score -1·36, 95% CI -1·44 to -1·27, weight-for-age Z score -1·20, -1·28 to -1·11, and head circumference Z score -0·51, -0·59 to -0·43). The prevalence of stunting and underweight remained unacceptably high (30·0%, 95% CI 27·0-33·0, for stunting and 22·1%, 19·4 to 24·8, for underweight)., Interpretation: A combination of nutrition-sensitive and nutrition-specific interventions has achieved a halving of undernutrition rates, but despite these intensive interventions substantial growth faltering remains. We need to understand the missing contributors to growth faltering to guide development of new interventions., Funding: UK Medical Research Council, UK Department for International Development., (Copyright © 2017 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY license. Published by Elsevier Ltd.. All rights reserved.)

The estimated heritability of human BMI is close to 75%, but identified genetic variants explain only a small fraction of interindividual body-weight variation. Inherited epigenetic variants identified in mouse models named "metastable epialleles" could in principle explain this "missing heritability." We provide evidence that methylation in a variably methylated region (VMR) in the pro-opiomelanocortin gene (POMC), particularly in postmortem human laser-microdissected melanocyte-stimulating hormone (MSH)-positive neurons, is strongly associated with individual BMI. Using cohorts from different ethnic backgrounds, including a Gambian cohort, we found evidence suggesting that methylation of the POMC VMR is established in the early embryo and that offspring methylation correlates with the paternal somatic methylation pattern. Furthermore, it is associated with levels of maternal one-carbon metabolites at conception and stable during postnatal life. Together, these data suggest that the POMC VMR may be a human metastable epiallele that influences body-weight regulation., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Context: Ethnic groups differ in fragility fracture risk and bone metabolism. Differences in diurnal rhythms (DRs) of bone turnover and PTH may play a role., Objective: We investigated the DRs of plasma bone turnover markers (BTMs), PTH, and 1,25(OH)2D in three groups with pronounced differences in bone metabolism and plasma PTH., Participants: Healthy Gambian, Chinese, and white British adults (ages 60-75 years; 30 per country)., Interventions: Observational study with sample collection every 4 hours for 24 hours., Main Outcomes: Levels of plasma C-terminal telopeptide of type I collagen, procollagen type-1 N-propeptide, N-mid osteocalcin, bone alkaline phosphatase, PTH, and 1,25-dihydroxyvitamin D were measured. DRs were analyzed with random-effects Fourier regression and cross-correlation and regression analyses to assess associations between DRs and fasting and 24-hour means of BTMs and PTH., Results: Concentrations of BTMs, PTH, and 1,25-dihydroxyvitamin D were higher in Gambians compared to other groups (P < .05). The DRs were significant for all variables and groups (P < .03) and were unimodal, with a nocturnal peak and a daytime nadir for BTMs, whereas PTH had two peaks. The DRs of BTMs and PTH were significantly cross-correlated for all groups (P < .05). There was a significant positive association between C-terminal telopeptide of type I collagen and PTH in the British and Gambian groups (P = .03), but not the Chinese group., Conclusions: Despite ethnic differences in plasma BTMs and PTH, DRs were similar. This indicates that alteration of rhythmicity and loss of coupling of bone resorption and formation associated with an elevated PTH in other studies may not uniformly occur across different populations and needs to be considered in the interpretation of PTH as a risk factor of increased bone loss.

The extent to which animals respond fearfully to novel stimuli may critically influence their ability to survive alongside humans. However, it is unclear whether the fear of novel objects, object neophobia, consistently varies in response to human disturbance. Where variation has been documented, it is unclear whether this variation is due to a change in fear towards specific novel stimuli, or whether it is symptomatic of a general change in fear behaviour. We measured levels of object neophobia in free-flying birds across urban and rural habitats, comparing corvids, a family known for being behaviourally flexible and innovative, with other urban-adapting bird species. Neophobic responses were measured in the presence of different types of objects that varied in their novelty, and were compared to behaviour during a baited control. Corvids were more neophobic than noncorvid species towards all object types, but their hesitancy abated after conspecifics approached in experimental conditions in which objects resembled items they may have experienced previously. Both sets of species were faster to approach objects made from human litter in urban than rural areas, potentially reflecting a category-specific reduction in fear based on experience. These results highlight species similarities in behavioural responses to human-dominated environments despite large differences in baseline neophobia.

Background: Maternal micronutrient deficiencies are commonly associated with clinical indicators of placental dysfunction., Objective: We tested the hypothesis that periconceptional multiple-micronutrient supplementation (MMS) affects placental function., Design: We conducted a double-blind, randomized, placebo-controlled trial of MMS in 17- to 45-y-old Gambian women who were menstruating regularly and within the previous 3 mo. Eligible subjects were pre-randomly assigned to supplementation with the UNICEF/WHO/United Nations University multiple micronutrient preparation (UNIMMAP) or placebo on recruitment and until they reached their first antenatal check-up or for 1 y if they failed to conceive. Primary outcome measures were midgestational indexes of utero-placental vascular-endothelial function [ratio of plasminogen-activator inhibitor (PAI) 1 to PAI-2 and mean uterine-artery resistance index (UtARI)] and placental active transport capacity at delivery [fetal to maternal measles antibody (MMA) ratio]., Results: We recruited 1156 women who yielded 415 pregnancies, of which 376 met all of the inclusion criteria. With adjustment for gestational age at sampling, there were no differences in PAI-1 to PAI-2 or MMA ratios between trial arms, but there was a 0.02-unit reduction in UtARI between 18 and 32 wk of gestation (95% CI: -0.03, -0.00; P = 0.040) in women taking UNIMMAP., Conclusions: Placental vascular function was modifiable by periconceptional micronutrient supplementation. However, the effect was small and supplementation did not further affect other variables of placental function. This trial was registered at www.controlled-trials.com as ISRCTN 13687662.

Iron deficiency is the most common nutrient deficiency worldwide and routine supplementation is standard policy for pregnant mothers and children in most low-income countries. However, iron lies at the center of host-pathogen competition for nutritional resources and recent trials of iron administration in African and Asian children have resulted in significant excesses of serious adverse events including hospitalizations and deaths. Increased rates of malaria, respiratory infections, severe diarrhea and febrile illnesses of unknown origin have all been reported, but the mechanisms are unclear. We here investigated the ex vivo growth characteristics of exemplar sentinel bacteria in adult sera collected before and 4 h after oral supplementation with 2 mg/kg iron as ferrous sulfate. Escherichia coli, Yersinia enterocolitica and Salmonella enterica serovar Typhimurium (all gram-negative bacteria) and Staphylococcus epidermidis (gram-positive) showed markedly elevated growth in serum collected after iron supplementation. Growth rates were very strongly correlated with transferrin saturation (p < 0.0001 in all cases). Growth of Staphylococcus aureus, which preferentially scavenges heme iron, was unaffected. These data suggest that even modest oral supplements with highly soluble (non-physiological) iron, as typically used in low-income settings, could promote bacteremia by accelerating early phase bacterial growth prior to the induction of immune defenses.

The aim of this study was to estimate the burden of childhood rickets-like bone deformity in a rural region of West Africa where rickets has been reported in association with a low calcium intake. A population-based survey of children aged 0.5-17.9 years living in the province of West Kiang, The Gambia was conducted in 2007. 6221 children, 92% of those recorded in a recent census, were screened for physical signs of rickets by a trained survey team with clinical referral of suspected cases. Several objective measures were tested as potential screening tools. The prevalence of bone deformity in children <18.0 years was 3.3%. The prevalence was greater in males (M = 4.3%, F = 2.3%, p < 0.001) and in children <5.0 years (5.7%, M = 8.3%, F = 2.9%). Knock-knee was more common (58%) than bow-leg (31%) or windswept deformity (9%). Of the 196 examined clinically, 36 were confirmed to have a deformity outside normal variation (47% knock-knee, 53% bow-leg), resulting in more conservative prevalence estimates of bone deformity: 0.6% for children <18.0 years (M = 0.9%, F = 0.2%), 1.5% for children < 5.0 years (M = 2.3%, F = 0.6%). Three of these children (9% of those with clinically-confirmed deformity, 0.05% of those screened) had active rickets on X-ray at the time of medical examination. This emphasises the difficulties in comparing prevalence estimates of rickets-like bone deformities from population surveys and clinic-based studies. Interpopliteal distance showed promise as an objective screening measure for bow-leg deformity. In conclusion, this population survey in a rural region of West Africa with a low calcium diet has demonstrated a significant burden of rickets-like bone deformity, whether based on physical signs under survey conditions or after clinical examination, especially in boys < 5.0 years., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

Human ovulation is not advertised, as it is in several primate species, by conspicuous sexual swellings. However, there is increasing evidence that the attractiveness of women's body odor, voice, and facial appearance peak during the fertile phase of their ovulatory cycle. Cycle effects on facial attractiveness may be underpinned by changes in facial skin color, but it is not clear if skin color varies cyclically in humans or if any changes are detectable. To test these questions we photographed women daily for at least one cycle. Changes in facial skin redness and luminance were then quantified by mapping the digital images to human long, medium, and shortwave visual receptors. We find cyclic variation in skin redness, but not luminance. Redness decreases rapidly after menstrual onset, increases in the days before ovulation, and remains high through the luteal phase. However, we also show that this variation is unlikely to be detectable by the human visual system. We conclude that changes in skin color are not responsible for the effects of the ovulatory cycle on women's attractiveness.

Background: Interindividual epigenetic variation that occurs systemically must be established prior to gastrulation in the very early embryo and, because it is systemic, can be assessed in easily biopsiable tissues. We employ two independent genome-wide approaches to search for such variants., Results: First, we screen for metastable epialleles by performing genomewide bisulfite sequencing in peripheral blood lymphocyte (PBL) and hair follicle DNA from two Caucasian adults. Second, we conduct a genomewide screen for genomic regions at which PBL DNA methylation is affected by season of conception in rural Gambia. Remarkably, both approaches identify the genomically imprinted VTRNA2-1 as a top environmentally responsive epiallele. We demonstrate systemic and stochastic interindividual variation in DNA methylation at the VTRNA2-1 differentially methylated region in healthy Caucasian and Asian adults and show, in rural Gambians, that periconceptional environment affects offspring VTRNA2-1 epigenotype, which is stable over at least 10 years. This unbiased screen also identifies over 100 additional candidate metastable epialleles, and shows that these are associated with cis genomic features including transposable elements., Conclusions: The non-coding VTRNA2-1 transcript (also called nc886) is a putative tumor suppressor and modulator of innate immunity. Thus, these data indicating environmentally induced loss of imprinting at VTRNA2-1 constitute a plausible causal pathway linking early embryonic environment, epigenetic alteration, and human disease. More broadly, the list of candidate metastable epialleles provides a resource for future studies of epigenetic variation and human disease.

Background: In populations of European ancestry, the genetic contribution to body mass index (BMI) increases with age during childhood but then declines during adulthood, possibly due to the cumulative effects of environmental factors. How the effects of genetic factors on BMI change with age in other populations is unknown., Subjects and Methods: In a rural Gambian population (N=2535), we used a combined allele risk score, comprising genotypes at 28 'Caucasian adult BMI-associated' single nucleotide polymorphisms (SNPs), as a marker of the genetic influence on body composition, and related this to internally-standardised z-scores for birthweight (zBW), weight-for-height (zWT-HT), weight-for-age (zWT), height-for-age (zHT), and zBMI cross-sectionally and longitudinally., Results: Cross-sectionally, the genetic score was positively associated with adult zWT (0.018±0.009 per allele, p=0.034, N=1426) and zWT-HT (0.025±0.009, p=0.006), but not with size at birth or childhood zWT-HT (0.008±0.005, p=0.11, N=2211). The effect of the genetic score on zWT-HT strengthened linearly with age from birth through to late adulthood (age interaction term: 0.0083 z-scores/allele/year; 95% CI 0.0048 to 0.0118, p=0.0000032)., Conclusions: Genetic variants for obesity in populations of European ancestry have direct relevance to bodyweight in nutritionally deprived African settings. In such settings, genetic obesity susceptibility appears to regulate change in weight status throughout the life course, which provides insight into its potential physiological role., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Seasonal variations are rarely considered a contributing component to human tissue function or health, although many diseases and physiological process display annual periodicities. Here we find more than 4,000 protein-coding mRNAs in white blood cells and adipose tissue to have seasonal expression profiles, with inverted patterns observed between Europe and Oceania. We also find the cellular composition of blood to vary by season, and these changes, which differ between the United Kingdom and The Gambia, could explain the gene expression periodicity. With regards to tissue function, the immune system has a profound pro-inflammatory transcriptomic profile during European winter, with increased levels of soluble IL-6 receptor and C-reactive protein, risk biomarkers for cardiovascular, psychiatric and autoimmune diseases that have peak incidences in winter. Circannual rhythms thus require further exploration as contributors to various aspects of human physiology and disease.

The mechanisms underpinning stress-related behavior and dysfunctional events leading to the expression of neuropsychiatric disorders remain incompletely understood. Novel candidates involved in the neuromodulation of stress, mediated both peripherally and centrally, provide opportunities for improved understanding of the neurobiological basis of stress disorders and may represent targets for novel therapeutic development. This chapter provides an overview of the mechanisms by which the opioid-related peptide, nociceptin, regulates the neuroendocrine stress response and stress-related behavior. In our research, we have employed nociceptin receptor antagonists to investigate endogenous nociceptin function in tonic control over stress-induced activity of the hypothalamo-pituitary-adrenal axis. Nociceptin demonstrates a wide range of functions, including modulation of psychological and inflammatory stress responses, modulation of neurotransmitter release, immune homeostasis, in addition to anxiety and cognitive behaviors. Greater appreciation of the complexity of limbic-hypothalamic neuronal networks, together with attention toward gender differences and the roles of steroid hormones, provides an opportunity for deeper understanding of the importance of the nociceptin system in the context of the neurobiology of stress and behavior., (© 2015 Elsevier Inc. All rights reserved.)

Background: PERIODIC OR CYCLIC DATA OF KNOWN PERIODICITY ARE FREQUENTLY ENCOUNTERED IN EPIDEMIOLOGICAL AND BIOMEDICAL RESEARCH: for instance, seasonality provides a useful experiment of nature while diurnal rhythms play an important role in endocrine secretion. There is, however, little consensus on how to analysis these data and less still on how to measure association or effect size for the often complex patterns seen., Results: A simple statistic, readily derived from Fourier regression models, provides a readily-understood measure cyclic variation in a wide variety of situations., Conclusion: The coefficient of cyclic variation or similar statistics derived from the variance of a Fourier series could provide a universal means of summarising the magnitude of periodic variation.

In experimental animals, maternal diet during the periconceptional period influences the establishment of DNA methylation at metastable epialleles in the offspring, with permanent phenotypic consequences. Pronounced naturally occurring seasonal differences in the diet of rural Gambian women allowed us to test this in humans. We show that significant seasonal variations in methyl-donor nutrient intake of mothers around the time of conception influence 13 relevant plasma biomarkers. The level of several of these maternal biomarkers predicts increased/decreased methylation at metastable epialleles in DNA extracted from lymphocytes and hair follicles in infants postnatally. Our results demonstrate that maternal nutritional status during early pregnancy causes persistent and systemic epigenetic changes at human metastable epialleles.

Background: Vitamin A supplementation significantly reduces all-cause mortality when given between 6-59 months of age, but has a null or detrimental effect when given between 1-5 months. Studies of neonatal vitamin A supplementation conducted across Africa and South Asia have produced conflicting findings. These age-pattern variations might result from immunological interactions between vitamin A supplementation and vaccines. Knowledge on the potential immunological sequelae of human neonatal vitamin A supplementation is so scarce that the foremost aim of this study is to seek indicative data on aspects of immunity likely to be affected by neonatal vitamin A supplementation. The objective of this trial is to test whether human neonatal vitamin A supplementation modulates immune function including improved thymic maturation in infancy and improved systemic immune responses to routine immunization., Methods/design: In an area of moderate vitamin A deficiency in a peri-urban area of The Gambia, 200 mother-infant pairs were enrolled in a double-blind randomised controlled trial. Within 48 hours of birth, neonates were randomised with stratification by birth weight and sex to receive either an oral dose of 50,000 IU vitamin A or placebo. Expanded Programme of Immunisation birth vaccinations were administered after supplementation, with subsequent vaccinations administered at 8, 12 and 16 weeks of age. A range of immunological outcomes were examined up to 17 weeks of age, with additional morbidity and anthropometry follow-up carried out throughout the first year of life. The primary endpoint of this trial is the frequency of circulating T regulatory (Treg) cells expressing gut homing receptors in infants at 17 week post-supplementation, with secondary outcomes including thymus maturation and B cell immune responses., Discussion: Indicative immunological data from this trial (and its Bangladeshi counterpart), will complement the larger randomised controlled trials (conducted in India, Tanzania and Ghana), on the effectiveness and safety of neonatal vitamin A supplementation in improving infant survival. Combined these trials, in addition to the existing trials, will inform policy., Trial Registration: clinicaltrials.gov NCT01476358.

Background: Data from West Africa indicate that a small thymus at birth and at 6 months of age is a strong and independent risk factor for infection-related mortality up to 24 and 36 months of age, respectively. We investigated the association between thymus size (thymic index, TI) in infancy and subsequent infant and child survival in a contemporary South Asian population., Methods: The study focused on the follow-up of a randomized trial of prenatal nutritional interventions in rural Bangladesh (ISRCTN16581394), with TI measured longitudinally in infancy (at birth and weeks 8, 24 and 52 of age) and accurate recording of mortality up to 5 years of age., Results: A total of 3267 infants were born into the Maternal and Infant Nutrition Interventions, Matlab study; data on TI were available for 1168 infants at birth, increasing to 2094 infants by 52 weeks of age. TI in relation to body size was largest at birth, decreasing through infancy. For infants with at least one measure of TI available, there were a total of 99 deaths up to the age of 5 years. No association was observed between TI and subsequent mortality when TI was measured at birth. However, an association with mortality was observed with TI at 8 weeks of age [odds ratio (OR) for change in mortality risk associated with 1 standard deviation change in TI: all deaths: OR = 0.64, 95% confidence interval (CI) 0.41, 0.98; P = 0.038; and infection-related deaths only: OR = 0.32, 95% CI 0.14, 0.74; P = 0.008]. For TI when measured at 24 and 52 weeks of age, the numbers of infection-related deaths were too few (3 and 1, respectively) for any meaningful association to be observed., Conclusion: These results confirm that thymus size in early infancy predicts subsequent survival in a lower mortality setting than West Africa. The absence of an effect at birth and its appearance at 8 weeks of age suggests early postnatal influences such as breast milk trophic factors.

Objective: Emerging evidence from animal models suggests that translocation of bacterial debris across a leaky gut may trigger low-grade inflammation, which in turn drives insulin resistance. The current study set out to investigate this phenomenon, termed 'metabolic endotoxemia', in Gambian women., Methods: In a cross-sectional study, we recruited 93 age-matched middle-aged urban Gambian women into three groups: lean (body mass index (BMI): 18.5-22.9 kg m(-2)), obese non-diabetic (BMI: 30.0 kg m(-2)) and obese diabetic (BMI: 30.0 kg m(-2) and attending a diabetic clinic). We measured serum bacterial lipopolysaccharide (LPS) and endotoxin-core IgM and IgG antibodies (EndoCAb) as measures of endotoxin exposure and interleukin-6 (IL-6) as a marker of inflammation., Results: Inflammation (IL-6) was independently and positively associated with both obesity and diabetes (F=12.7, P<0.001). LPS levels were highest in the obese-diabetic group compared with the other two groups (F=4.4, P<0.02). IgM EndoCAb (but not total IgM) was highly significantly reduced in the obese (55% of lean value) and obese diabetic women (30% of lean; F=21.7, P<0.0001 for trend) compared with lean women., Conclusion: These data support the hypothesis that gut-derived inflammatory products are associated with obesity and diabetes. Confirmation of these findings and elucidation of the role of the microbiota, gut damage and the pathways for translocation of bacterial debris, could open new avenues for prevention and treatment of type 2 diabetes.

Objective: To determine if low-dose weekly chloroquine (CQ) therapy improves recovery from malaria-associated anaemia., Design: Proof of concept randomised clinical trial., Setting: West Kiang District, Lower River Region, The Gambia., Participants: Children resident in participating communities, aged 12-72 months, with uncomplicated malaria identified using active case detection over two consecutive malaria transmission seasons., Interventions: In 2007, eligible children were randomised to chloroquine-sulfadoxine/pyrimethamine (CQ-SP) or co-artemether (ACT) antimalarial therapy, and after parasite clearance on day 3 were subsequently re-randomised (double-blind) to weekly low-dose CQ (5 mg/kg) or placebo. In 2008, all eligible children were treated with ACT and subsequently randomised to CQ or placebo., Outcome Measures: The primary outcome was a change in haemoglobin from baseline (day 3 of antimalarial treatment) to day 90 in the CQ and placebo treatment arms. Secondary outcomes were changes in urinary neopterin as a marker of macrophage activation, markers of erythropoietic response and prevalence of submicroscopic parasitaemia. Change in haemoglobin in the placebo arm by initial antimalarial treatment was also assessed., Results: In 2007, 101 children with uncomplicated malaria were randomised to antimalarial treatment with CQ-SP or ACT and 65 were subsequently randomised to weekly CQ or placebo. In 2008, all children received ACT antimalarial treatment and 31 were subsequently randomised to receive weekly CQ or placebo. Follow-up to day 90 was 96%. There was no effect of weekly CQ vs placebo on change in haemoglobin at day 90 (CQ+10.04 g/L (95% CI 6.66 to 13.42) vs placebo +7.61 g/L (95% CI 2.88 to 12.35)). There was no effect on the secondary outcomes assessed, or effect of initial antimalarial therapy on haemoglobin recovery. Higher day 90 haemoglobin correlated independently with older age, not being stunted, higher haemoglobin at day 0 and adequate iron status at day 3., Conclusions: Weekly low-dose CQ after effective antimalarial treatment is not effective in improving recovery from postmalarial anaemia., Trial Registration: The clinical trial registration number is NCT00473837 (ClinicalTrials.gov).

Objectives: Studies testing whether systemic inflammation might lie on the causal pathway between aberrant fetal and post-natal growth patterns and later cardiovascular disease have been inconclusive, possibly due to the use of single markers of unknown predictive value. We used repeated measures of a comprehensive set of inflammatory markers to investigate the relationship between early life measures and systemic inflammation in an African population., Methods: Individuals born in three rural villages in The Gambia, and for whom early life measurements were recorded, were traced (n = 320). Fasting levels of eight inflammatory markers (C-reactive protein, serum amyloid A, orosomucoid, fibrinogen, α 1-antichymotrypsin, sialic acid, interleukin-6 and neopterin) were measured, and potential confounding factors recorded. The association between early life measurements and systemic inflammation was assessed using regression analysis., Results: Levels of most markers were unrelated to early growth patterns. In analyses adjusted for age and sex, more rapid growth between birth and 3 months of age was associated with higher levels of fibrinogen, orosomucoid, and sialic acid. These relationships persisted after further adjustment for body mass index but after full adjustment only the association with fibrinogen remained., Conclusions: This study provides little evidence that size at birth or growth in early infancy determine levels of inflammatory markers in young Gambian adults., (Copyright © 2013 Wiley Periodicals, Inc.)

Prenatal events can affect neonatal thymus size and adult immune function. The causal insults are unknown, although fetal nutrient restriction is suspected. We used ultrasound at three time points during pregnancy (14, 19 and 30 weeks) to measure the growth of six fetal dimensions in rural Bangladeshi women participating in the Maternal and Infant Nutrition Interventions, Matlab study. Postnatal ultrasound was used to calculate thymic index (TI) at birth, 2, 6 and 12 m. Of the 3267 women recruited, 2861 participated by providing data at least at one fetal biometry and one TI time point. Patterns of fetal growth were summarized using principal components calculated from fetal dimension z-scores. Random effects regression, controlling for infant size and season of measurement were used to relate these patterns to TI. We found that smaller leg length relative to head circumference, characteristic of head-sparing growth restriction, was predictive of lower TI. This association was significant at all time points but strongest in earlier pregnancy. Each standard deviation increase in leg-head proportion was associated with an increase in TI of ∼5%. We conclude that growth patterns typical of poor fetal nutrition are associated with poor thymic development. The greater strength of this association in the first trimester is consistent with a period of vulnerability during the early ontogeny of the thymus and suggests that preventative intervention would need to be given in early pregnancy.

Background: Animal models show that periconceptional supplementation with folic acid, vitamin B-12, choline, and betaine can induce differences in offspring phenotype mediated by epigenetic changes in DNA. In humans, altered DNA methylation patterns have been observed in offspring whose mothers were exposed to famine or who conceived in the Gambian rainy season., Objective: The objective was to understand the seasonality of DNA methylation patterns in rural Gambian women. We studied natural variations in dietary intake of nutrients involved in methyl-donor pathways and their effect on the respective metabolic biomarkers., Design: In 30 women of reproductive age (18-45 y), we monitored diets monthly for 1 y by using 48-h weighed records to measure intakes of choline, betaine, folate, methionine, riboflavin, and vitamins B-6 and B-12. Blood biomarkers of these nutrients, S-adenosylhomocysteine (SAH), S-adenosylmethionine (SAM), homocysteine, cysteine, and dimethylglycine were also assessed monthly., Results: Dietary intakes of riboflavin, folate, choline, and betaine varied significantly by season; the most dramatic variation was seen for betaine. All metabolic biomarkers showed significant seasonality, and vitamin B-6 and folate had the highest fluctuations. Correlations between dietary intakes and blood biomarkers were found for riboflavin, vitamin B-6, active vitamin B-12 (holotranscobalamin), and betaine. We observed a seasonal switch between the betaine and folate pathways and a probable limiting role of riboflavin in these processes and a higher SAM/SAH ratio during the rainy season., Conclusions: Naturally occurring seasonal variations in food-consumption patterns have a profound effect on methyl-donor biomarker status. The direction of these changes was consistent with previously reported differences in methylation of metastable epialleles. This trial was registered at www.clinicaltrials.gov as NCT01811641.

Recent human history is marked by demographic transitions characterized by declines in mortality and fertility. By influencing the variance in those fitness components, demographic transitions can affect selection on other traits. Parallel to changes in selection triggered by demography per se, relationships between fitness and anthropometric traits are also expected to change due to modification of the environment. Here we explore for the first time these two main evolutionary consequences of demographic transitions using a unique data set containing survival, fertility, and anthropometric data for thousands of women in rural Gambia from 1956-2010. We show how the demographic transition influenced directional selection on height and body mass index (BMI). We observed a change in selection for both traits mediated by variation in fertility: selection initially favored short females with high BMI values but shifted across the demographic transition to favor tall females with low BMI values. We demonstrate that these differences resulted both from changes in fitness variance that shape the strength of selection and from shifts in selective pressures triggered by environmental changes. These results suggest that demographic and environmental trends encountered by current human populations worldwide are likely to modify, but not stop, natural selection in humans., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

An analysis of early growth patterns in children from 54 resource-poor countries in Africa and Southeast Asia shows a rapid falloff in the height-for-age z score during the first 2 y of life and no recovery until ≥5 y of age. This finding has focused attention on the period -9 to 24 mo as a window of opportunity for interventions against stunting and has garnered considerable political backing for investment targeted at the first 1000 d. These important initiatives should not be undermined, but the objective of this study was to counteract the growing impression that interventions outside of this period cannot be effective. We illustrate our arguments using longitudinal data from the Consortium of Health Oriented Research in Transitioning collaboration (Brazil, Guatemala, India, Philippines, and South Africa) and our own cross-sectional and longitudinal growth data from rural Gambia. We show that substantial height catch-up occurs between 24 mo and midchildhood and again between midchildhood and adulthood, even in the absence of any interventions. Longitudinal growth data from rural Gambia also illustrate that an extended pubertal growth phase allows very considerable height recovery, especially in girls during adolescence. In light of the critical importance of maternal stature to her children's health, our arguments are a reminder of the importance of the more comprehensive UNICEF/Sub-Committee on Nutrition Through the Life-Cycle approach. In particular, we argue that adolescence represents an additional window of opportunity during which substantial life cycle and intergenerational effects can be accrued. The regulation of such growth is complex and may be affected by nutritional interventions imposed many years previously.

Observational evidence suggests nutritional exposures during in utero development may have long-lasting consequences for health; data from interventions are scarce. Here, we present a trial follow-up study to assess the association between prenatal food and micronutrient supplementation and childhood blood pressure and kidney function. During the MINIMat Trial in rural Bangladesh, women were randomly assigned early in pregnancy to receive an early or later invitation to attend a food supplementation program and additionally to receive either iron and folate or multiple micronutrient tablets daily. The 3267 singleton birth individuals with measured anthropometry born during the trial were eligible for a follow-up study at 4.5 y old. A total of 77% of eligible individuals were recruited and blood pressure, kidney size by ultrasound, and glomerular filtration rate (GFR; calculated from plasma cystatin c) were assessed. In adjusted analysis, early invitation to food supplementation was associated with a 0.72-mm Hg [(95% CI: 0.16, 1.28); P = 0.01] lower childhood diastolic blood pressure and maternal MMS supplementation was associated with a marginally higher [0.87 mm Hg (95% CI: 0.18, 1.56); P = 0.01] childhood diastolic blood pressure. There was also some evidence that a supplement higher in iron was associated with a higher offspring GFR. No other effects of the food or micronutrient interventions were observed and there was no interaction between the interventions on the outcomes studied. These marginal associations and small effect sizes suggest limited public health importance in early childhood.

Background: Chronic exposure to toxic metals such as arsenic and cadmium has been implicated in the development of kidney and cardiovascular diseases but few studies have directly measured exposure during inutero and early child development., Methods: We investigated the impact of exposure to arsenic (mainly in drinking water) and cadmium (mainly in rice) during pregnancy on blood pressure and kidney function at 4.5 years of age in rural Bangladesh. The effect of arsenic exposure in infancy was also assessed., Results: Within a cohort of 1887 children recruited into the MINIMat study, exposure to arsenic (maternal urinary arsenic, U-As), but not cadmium, during in utero development was associated with a minimal increase in blood pressure at 4.5 years. Each 1 mg/l increase in pregnancy U-As was associated with 3.69 mmHg (95% CI: 0.74, 6.63; P: 0.01) increase in child systolic and a 2.91 mmHg (95% CI: 0.41, 5.42; P: 0.02) increase in child diastolic blood pressure. Similarly, a 1 mg/l increase in child U-As at 18 months of age was associated with a 8.25 mmHg (95% CI: 1.37, 15.1; P: 0.02) increase in systolic blood pressure at 4.5 years. There was also a marginal inverse association between infancy U-As and glomerular filtration rate at 4.5 years (-33.4 ml/min/1.72 m(2); 95% CI: -70.2, 3.34; P: 0.08). No association was observed between early arsenic or cadmium exposure and kidney volume at 4.5 years assessed by ultrasound., Conclusions: These modest effect sizes provide some evidence that arsenic exposure in early life has long-term consequences for blood pressure and maybe kidney function.

Meta-analysis of growth data from over 50 low and low-middle income countries shows a consistent pattern of stunting and poor weight gain from about 3 months of age and persisting until at least 5 years. Children tend not to be wasted because their short stature offsets their underweight, leading to a rather adequately proportioned appearance. This frequently conceals the true levels of malnutrition in communities. At the macro-environmental level such growth faltering is due to the combined effects of poverty, food insecurity, low-dietary diversity, a highly infectious environment, poor washing facilities and poor understanding of the principles of nutrition and hygiene. These tend to be ameliorated as communities pass through the demographic transition with improved incomes and education. Because such changes will take generations to achieve, the global health community continues to search for effective interim solutions. Disappointingly, apart from intensive feeding programmes aimed at rehabilitating severely malnourished children, there are few examples of very successful nutrition interventions. This emphasizes the need for a better understanding of the etiology of growth failure. This paper uses anthropometric data collected over 6 decades in subsistence-farming communities from rural Gambia to illustrate the typical key features of growth faltering. Arising from this analysis, and from gaps in the published literature, the following issues are highlighted as still requiring a better resolution: (1) the pre-natal and inter-generational influences on growth failure; (2) the ontogeny of the infant immune system; (3) the exact nature of the precipitating insults that initiate gastroenteropathy; (4) the effects of both enteric and systemic infections on the hormonal regulation of growth; (5) interactions between macro- and micro-nutrient deficiencies and infections in causing growth failure, and (6) the role of the microbiome in modulating dietary influences on health and growth., (Copyright © 2013 S. Karger AG, Basel.)

Birth weight within the normal range is associated with a variety of adult-onset diseases, but the mechanisms behind these associations are poorly understood. Previous genome-wide association studies of birth weight identified a variant in the ADCY5 gene associated both with birth weight and type 2 diabetes and a second variant, near CCNL1, with no obvious link to adult traits. In an expanded genome-wide association meta-analysis and follow-up study of birth weight (of up to 69,308 individuals of European descent from 43 studies), we have now extended the number of loci associated at genome-wide significance to 7, accounting for a similar proportion of variance as maternal smoking. Five of the loci are known to be associated with other phenotypes: ADCY5 and CDKAL1 with type 2 diabetes, ADRB1 with adult blood pressure and HMGA2 and LCORL with adult height. Our findings highlight genetic links between fetal growth and postnatal growth and metabolism.

Background: Intestinal damage and malabsorption caused by chronic environmental enteropathy are associated with growth faltering seen in infants in less-developed countries. Evidence has suggested that supplementary omega-3 (n-3) long-chain PUFAs (LC-PUFAs) might ameliorate this damage by reducing gastrointestinal inflammation. LC-PUFA supplementation may also benefit cognitive development., Objective: We tested whether early n-3 LC-PUFA supplementation improves infant intestinal integrity, growth, and cognitive function., Design: A randomized, double-blind, controlled trial [200 mg DHA and 300 mg EPA or 2 mL olive oil/d for 6 mo] was conducted in a population of 172 rural Gambian infants aged 3-9 mo. The primary endpoints were anthropometric measures and gut integrity [assessed by using urinary lactulose:mannitol ratios (LMRs)]. Plasma fatty acid status, intestinal mucosal inflammation (fecal calprotectin), daily morbidity, and cognitive development (2-step means-end test and an attention assessment) were secondary endpoints., Results: PUFA supplementation resulted in a significant increase in plasma n-3 LC-PUFA concentrations (P < 0.001 for both DHA and EPA) and midupper arm circumference (MUAC) (effect size: 0.31 z scores; 95% CI: 0.06, 0.56; P = 0.017) at 9 mo of age. At 12 mo, MUAC remained greater in the intervention group, and we observed significant increases in skinfold thicknesses (P ≤ 0.022 for all). No other significant differences between treatment groups were detected for growth or LMRs at 9 mo or for secondary outcomes., Conclusions: Fish-oil supplementation successfully increased plasma n-3 fatty acid status. However, in young, breastfed Gambian infants, the intervention failed to improve linear growth, intestinal integrity, morbidity, or selected measures of cognitive development. The trial was registered at www.isrctn.org as ISRCTN66645725.

Central nociceptin/orphanin FQ (N/OFQ)-expressing neurones are abundantly expressed in the hypothalamus and limbic system and are implicated in the regulation of activity of the hypothalamic-pituitary-adrenal axis (HPA) and stress responses. We investigated the role of the endogenous N/OFQ receptor (NOP) system using the nonpeptidic NOP antagonist, JTC-801 [N-(4-amino-2-methylquinolin-6-yl)-2-(4-ethylphenoxy-methyl)benzamide monohydrochloride], during the HPA axis response to acute physical/psychological stress (60 min of restraint). Although i.v. JTC-801 (0.05 mg/kg in 100 μl) had no significant effect on restraint-induced plasma corticosterone release at 30 or 60 min post-injection, i.v. JTC-801 (0.05 mg/kg in 100 μl) in quiescent rats significantly increased basal plasma corticosterone at the 30-min time-point compared to i.v. vehicle (1% dimethysulphoxide in sterile saline). Central injection of JTC-801 i.c.v. was associated with increased Fos expression in the parvocellular paraventricular nucleus 90 min after infusion compared to vehicle control. These findings contrast to the effects of i.c.v. UFP-101, a NOP antagonist that we have previously shown to have no effect on HPA activity in quiescent rats. To determine whether restraint stress was associated with compensatory changes in N/OFQ precursor (ppN/OFQ) or NOP receptor mRNAs, in a separate study, we undertook reverse transcriptase-polymerase chain reaction and in situ hybridisation analysis of ppN/OFQ and NOP transcripts in the brains of male Sprague-Dawley rats. In support of an endogenous role for central N/OFQ in psychological stress, we found that acute restraint significantly decreased preproN/OFQ transcript expression in the hippocampus 2 h after stress compared to unstressed controls. PpN/OFQ mRNA was also reduced in the mediodorsal forebrain 4 h after stress. NOP mRNA was reduced in the hypothalamus 2 h after restraint and at 4 h in mediodorsal forebrain and hippocampus. In situ hybridisation analysis showed that acute restraint significantly decreased ppNN/OFQ in the central amygdala, with significantly increased expression in bed nucleus and reticular thalamus associated with repeated restraint. There was a strong trend for reduced NOP mRNA in the bed nucleus of acute and repeated restraint groups, although there were no other significant changes seen. Although the exact mechanisms require elucidation, the findings obtained in the present study provide evidence indicating that the endogenous N/OFQ system is involved in both acute and chronic restraint stress responses. In summary, our findings confirm the significant role of endogenous NOP receptors and tonic N/OFQ function in the response to the psychological stress of restraint., (© 2012 The Authors. Journal of Neuroendocrinology © 2012 British Society for Neuroendocrinology.)

Environmental conditions experienced in early life can influence an individual's growth and long-term health, and potentially also that of their offspring. However, such developmental effects on intergenerational outcomes have rarely been studied. Here we investigate intergenerational effects of early environment in humans using survey- and clinic-based data from rural Gambia, a population experiencing substantial seasonal stress that influences foetal growth and has long-term effects on first-generation survival. Using Fourier regression to model seasonality, we test whether (i) parental birth season has intergenerational consequences for offspring in utero growth (1982 neonates, born 1976-2009) and (ii) whether such effects have been reduced by improvements to population health in recent decades. Contrary to our predictions, we show effects of maternal birth season on offspring birth weight and head circumference only in recent maternal cohorts born after 1975. Offspring birth weight varied according to maternal birth season from 2.85 to 3.03 kg among women born during 1975-1984 and from 2.84 to 3.41 kg among those born after 1984, but the seasonality effect reversed between these cohorts. These results were not mediated by differences in maternal age or parity. Equivalent patterns were observed for offspring head circumference (statistically significant) and length (not significant), but not for ponderal index. No relationships were found between paternal birth season and offspring neonatal anthropometrics. Our results indicate that even in rural populations living under conditions of relative affluence, brief variation in environmental conditions during maternal early life may exert long-term intergenerational effects on offspring.

Background: Recent observational research indicates that immune development may be programmed by nutritional exposures early in life. Such findings require replication from trials specifically designed to assess the impact of nutritional intervention during pregnancy on infant immune development. The current trial seeks to establish: (a) which combination of protein-energy (PE) and multiple-micronutrient (MMN) supplements would be most effective; and (b) the most critical periods for intervention in pregnancy and infancy, for optimal immune development in infancy., Methods/design: The ENID Trial is a 2 x 2 x 2 factorial randomized, partially blind trial to assess whether nutritional supplementation to pregnant women (from < 20 weeks gestation to term) and their infants (from 6 to 12 months of age) can enhance infant immune development. Eligible pregnant women from the West Kiang region of The Gambia (pregnancy dated by ultrasound examination) are randomized on entry to 4 intervention groups (Iron-folate (FeFol = standard care), multiple micronutrients (MMN), protein-energy (PE), PE + MMN). Women are visited at home weekly for supplement administration and morbidity assessment and seen at MRC Keneba at 20 and 30 weeks gestation for a detailed antenatal examination, including ultrasound. At delivery, cord blood and placental samples are collected, with detailed infant anthropometry collected within 72 hours. Infants are visited weekly thereafter for a morbidity questionnaire. From 6 to 12 months of age, infants are further randomized to a lipid-based nutritional supplement, with or without additional MMN. The primary outcome measures of this study are thymic development during infancy, and antibody response to vaccination. Measures of cellular markers of immunity will be made in a selected sub-cohort. Subsidiary studies to the main trial will additionally assess the impact of supplementation on infant growth and development to 24 months of age., Discussion: The proposed trial is designed to test whether nutritional repletion can enhance early immune development and, if so, to help determine the most efficacious form of nutritional support. Where there is evidence of benefit from a specific intervention/combination of interventions, future research should focus on refining the supplements to achieve the optimal, most cost-effective balance of interventions for improved health outcomes.

In humans and other mammals, some females are more likely to experience twin pregnancies than others, but the reasons behind such individual variation are poorly understood. One hypothesis invokes variation in the dynamics of the insulin-like growth factor (IGF) system, which also regulates foetal growth. Using data from a rural African population living in a highly seasonal environment, we test a novel prediction generated by this hypothesis, that maternal twinning status predicts offspring birthweight. We found that among singleton offspring who experience a favourable in utero environment (born January-June), births before and after twins are, respectively, associated with a 134.07 g and 226.41 g increase in birthweight compared with those born to non-twinning mothers. These results were not mediated by maternal anthropometry. This is consistent with a role for the IGF system in individual variation in twinning propensity, a possibility with implications for understanding mechanisms of life-history variation in humans and other vertebrates.

Background: Maternal nutritional intake during pregnancy may have important consequences for long-term health in offspring., Objective: The objective was to follow up the offspring in 2 randomized trials of nutrient supplementation during pregnancy to investigate the effect on cardiovascular disease (CVD) risk in offspring., Design: We recruited offspring born during 2 trials in The Gambia, West Africa. One trial provided protein-energy-dense food supplements (1015 kcal and 22 g protein/d) to pregnant (intervention, from 20 wk gestation until delivery) or lactating (control, for 20 wk from birth) women and was randomized at the village level. The second was a double-blind, individually randomized, placebo-controlled trial of calcium supplementation (1.5 g/d), which was also provided from 20 wk gestation until delivery., Results: Sixty-two percent (n = 1267) of children (aged 11-17 y) born during the protein-energy trial were recruited and included in the analysis, and 64% (n = 350) of children (aged 5-10 y) born during the calcium trial were recruited and included in the analysis. Fasted plasma glucose was marginally lower in children born to mothers receiving protein-energy supplements during pregnancy than in those children of the lactating group (adjusted mean difference: -0.05 mmol/L; 95% CI: -0.10, -0.001 mmol/L). There were no other differences in CVD risk factors, including blood pressure, body composition, and cholesterol, between children born to intervention and control women from the protein-energy trial. Maternal calcium supplementation during pregnancy was unrelated to offspring blood pressure., Conclusion: These data suggest that providing supplements to pregnant women in the second half of pregnancy may have little effect on the CVD risk of their offspring, at least in this setting and at the ages studied here. This trial was registered at www.controlled-trials.com as ISRCTN96502494.

Background: Reduced growth is common in children with sickle cell anemia, but few data exist on associations with long-term clinical course. Our objective was to determine the prevalence of malnutrition at enrollment into a hospital-based cohort and whether poor nutritional status predicted morbidity and mortality within an urban cohort of Tanzanian sickle cell anemia patients., Design and Methods: Anthropometry was conducted at enrollment into the sickle cell anemia cohort (n=1,618; ages 0.5-48 years) and in controls who attended screening (siblings, walk-ins and referrals) but who were found not to have sickle cell anemia (n=717; ages 0.5-64 years). Prospective surveillance recorded hospitalization at Muhimbili National Hospital and mortality between March 2004 and September 2009., Results: Sickle cell anemia was associated with stunting (OR=1.92, P<0.001, 36.2%) and wasting (OR=1.66, P=0.002, 18.4%). The greatest growth deficits were observed in adolescents and in boys. Independent of age and sex, lower hemoglobin concentration was associated with increased odds of malnutrition in sickle cell patients. Of the 1,041 sickle cell anemia patients with a body mass index z-score at enrollment, 92% were followed up until September 2009 (n=908) or death (n=50). Body mass index and weight-for-age z-score predicted hospitalization (hazard ratio [HZR]=0.90, P=0.04 and HZR=0.88, P=0.02) but height-for-age z-score did not (HZR=0.93, NS). The mortality rate of 2.5 per 100 person-years was not associated with any of the anthropometric measures., Conclusions: In this non-birth-cohort of sickle cell anemia with significant associated undernutrition, wasting predicted an increased risk of hospital admission. Targeted nutritional interventions should prioritize treatment and prevention of wasting.

Nociceptin (N/OFQ) peptide has regulatory roles in neuroendocrine responses to stress. We sought to clarify the roles of nociceptin and its receptors (NOP receptors) in the regulation of rat bed nucleus of the stria terminalis (BNST) neurones in vitro. The effect of nociceptin (75 nM) across subregions of the anterior BNST was determined using extracellular single-unit recordings in rat brain slices. Firing patterns of the neurones were recorded in the presence of N-methyl-D-aspartate (NMDA, 10 μm) for the classification of putative cell types. Based on the firing patterns, four cell types were identified. The distribution of cell types differed between the dorsal and ventral BNST. Nociceptin inhibited the activity of 53.2% of all the neurones tested (n = 47), regardless of the cell type or subregion. The duration of nociceptin-mediated inhibition of cell firing was significantly attenuated by pre-treatment with the NOP receptor antagonist, UFP-101 (750 nM), indicating that nociceptin-induced suppression of firing rate involves NOP receptor activation in the BNST. Pre-treatment of slices with 100-nM corticosterone (CORT) vs. dimethylsulphoxide (DMSO) for 20 min significantly abolished the nociceptin-induced inhibition of firing rate (P < 0.001) when tested 2 h later. We did not, however, observe a significant effect of CORT on baseline firing rate or pattern in BNST neurones. We suggest that the interaction between nociceptin and glucocorticoids in the BNST may be essential for normal adaptive stress responses.

Background: Evidence suggests that increased maternal calcium intake during pregnancy may result in lower offspring blood pressure, prompting calls for more robust data in this field, particularly in settings of habitually low calcium intake., Objective: The objective was to investigate the effect of maternal calcium supplementation on blood pressure in offspring by recruiting children born after a randomized, double-blind, placebo-controlled trial of calcium supplementation during pregnancy., Design: Children (n = 389) from a rural area of The Gambia (mean age: 7.4 ± 1.2 y; range: 5-10 y), whose mothers received a calcium supplement (1500 mg Ca/d from 20 wk of gestation until delivery) or placebo, were followed up in West Africa. Blood pressure was assessed under standardized conditions with use of the Omron 705IT automated oscillometric device (Morton Medical Ltd, London, United Kingdom), and anthropometric and body composition (bioelectrical impedance) measurements were also made., Results: The analysis was restricted to 350 children born at term, which represented 64% of original trial births. There was no difference in systolic (adjusted mean difference: -0.04 mm Hg; 95% CI: -1.78, 1.69 mm Hg) or diastolic (adjusted mean difference: 0.25 mm Hg; 95% CI: -1.27, 1.77 mm Hg) blood pressure between children whose mothers had received calcium and those who received placebo. No interaction between childhood body mass index (in kg/m(2); mean: 14.0) and maternal calcium supplementation was observed in this study., Conclusion: Calcium supplementation in the second half of pregnancy in Gambian women with very low habitual calcium intakes may not result in lower offspring blood pressure at 5-10 y of age.

Background: Numerous factors may influence Schistosoma infection intensity and prevalence within endemic communities, including exposure-related factors such as local environment and behaviour, and factors relating to susceptibility to infection such as immunology and genetics. While animal studies performed in the laboratory can be tightly controlled, human populations are highly heterogeneous, varying according to demographic characteristics, genetic background and exposure to infection. The heterogeneous nature of human water contact behaviour in particular makes it difficult to distinguish between a lack of cercarial exposure and reduced susceptibility to infection as the cause for low levels of infection in the field., Methods and Principal Findings: In this study we investigate risk factors for Schistosoma mansoni infection in a rural Ugandan fishing community receiving treatment as part of a multi-disciplinary longitudinal reinfection study. More specifically, we examine the influence that age, sex and ethnic background have on susceptibility to reinfection after anti-helminth drug treatment, but use individual estimates of cercarial exposure and multivariable methods in an attempt to remove noise created by environmental and behavioural heterogeneities. We then investigate whether schistosome-specific IgE immune responses could account for any remaining variations in susceptibility to reinfection. Our findings suggest that observed ethnic- and sex-related variations in S. mansoni reinfection were due to variations in cercarial exposure, as opposed to biological differences in susceptibility to infection. Age-related differences in reinfection were not explained by exposure, however, and appeared linked to the balance of IgE and IgG(4) to the tegumental antigen SmTAL1 (formerly Sm22.6), which itself was significantly related to resistance to reinfection., Conclusions: This study highlights the benefit of taking a multidisciplinary approach in complex field settings; it allows the ecology of a population to be understood and thus more robust conclusions to be made.

Menarcheal age is a key indicator of female maturity and development. Studies in many countries have reported a downward secular trend in age of menarche over the past century. This study presents data gained using the 'status quo' method and interval regression to estimate median menarcheal age of girls in a rural Gambian community. Cross-sectional studies carried out in 1989, 2000 and 2008 revealed a median menarcheal age of 16.06 (95% CI 15.67-16.45), 15.03 (95% CI 14.76-15.30) and 14.90 (95% CI 14.52-15.28), respectively. The average rate of decline of median age of menarche was amongst the most rapid yet reported, at 0.65 years of age per decade (p < 0.00001). There was no evidence for a change in the rate of decline over the two decades studied. These results probably reflect ongoing socio-economic development within the region.