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Dornisch SJ, Sievert LL, Sharmeen T, Begum K, Muttukrishna S, Chowdhury O, Bentley GR. Religious minority identity associates with stress and psychological health among Muslim and Hindu women in Bangladesh and London. Am J Hum Biol 2024:e24057. [PMID: 38415876 DOI: 10.1002/ajhb.24057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 02/14/2024] [Accepted: 02/15/2024] [Indexed: 02/29/2024] Open
Abstract
OBJECTIVES This study examined the association of minority religious identification (Hindu or Muslim) with self-reported stress and psychological symptoms among sedentee and immigrant Bangladeshi women. METHODS Women, aged 35-59 (n = 531) were drawn from Sylhet, Bangladesh and London, England. Muslim immigrants in London and Hindu sedentees in Sylhet represented minority religious identities. Muslim sedentees in Sylhet and Londoners of European descent represented majority religious identities. In bivariate analyses, minority religious identity was examined in relation to self-reported measures of stress, nervous tension, and depressed mood. Logistic regression was applied to examine the relationship between these variables while adjusting for marital status, parity, daily walking, and perceived financial comfort. RESULTS In bivariate analyses, religious minorities reported more stress than religious majorities in all group comparisons (p < .05), and minority Muslims reported more nervous tension and depressed mood than majority Muslims (p < .05). In logistic regression models, minority Muslims had greater odds of high stress than majority Muslims (OR 2.00, 95% CI 1.18-3.39). Minority Muslims had greater odds of stress (OR 3.05, 95% CI 1.51-6.17) and nervous tension (OR 3.37, 95% CI 1.66-6.87) than majority Londoners. Financial comfort reduced odds of stress and symptoms in all models. CONCLUSIONS Socioeconomic situation, immigration history, and minority ethnicity appear to influence the relationship between religious identity and psychosomatic symptoms in Bangladeshi women. Attention to personal and socioeconomic context is important for research examining the association between religion and mental health.
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Affiliation(s)
- S J Dornisch
- Department of Anthropology, UMass Amherst, Amherst, Massachusetts, USA
| | - L L Sievert
- Department of Anthropology, UMass Amherst, Amherst, Massachusetts, USA
| | - T Sharmeen
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - K Begum
- Department of Anthropology, Durham University, Durham, UK
| | - S Muttukrishna
- Department of Obstetrics and Gynecology, University College Cork, Cork, Ireland
| | - O Chowdhury
- Microbiology, Parkview Medical College, Sylhet, Bangladesh
| | - G R Bentley
- Department of Obstetrics and Gynecology, University College Cork, Cork, Ireland
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Stöger R, Choi M, Begum K, Leeman G, Emes RD, Melamed P, Bentley GR. Childhood environment influences epigenetic age and methylation concordance of a CpG clock locus in British-Bangladeshi migrants. Epigenetics 2023; 18:2153511. [PMID: 36495138 PMCID: PMC9980690 DOI: 10.1080/15592294.2022.2153511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Migration from one location to another often comes with a change in environmental conditions. Here, we analysed features of DNA methylation in young, adult British-Bangladeshi women who experienced different environments during their childhoods: a) migrants, who grew up in Bangladesh with exposure to comparatively higher pathogen loads and poorer health care, and b) second-generation British-Bangladeshis, born to Bangladeshi parents, who grew up in the UK. We used buccal DNA to estimate DNA methylation-based age (DNAm age) from 14 migrants and 11 second-generation migrants, aged 18-35 years. 'AgeAccel,' a measure of DNAm age, independent of chronological age, showed that the group of women who spent their childhood in Bangladesh had higher AgeAccel (P = 0.028), compared to their UK peers. Since epigenetic clocks have been proposed to be associated with maintenance processes of epigenetic systems, we evaluated the preference for concordant DNA methylation at the luteinizing hormone/choriogonadotropin receptor (LHCGR/LHR) locus, which harbours one of the CpGs contributing to Horvath's epigenetic clock. Measurements on both strands of individual, double-stranded DNA molecules indicate higher stability of DNA methylation states at this LHCGR/LHR locus in samples of women who grew up in Bangladesh. Together, our two independent analytical approaches imply that childhood environments may induce subtle changes that are detectable long after exposure occurred, which might reflect altered activity of the epigenetic maintenance system or a difference in the proportion of cell types in buccal tissue. This exploratory work supports our earlier findings that adverse childhood environments lead to phenotypic life history trade-offs.
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Affiliation(s)
- Reinhard Stöger
- School of Biosciences, University of Nottingham, Nottingham, UK
| | - Minseung Choi
- School of Medicine, Stanford University, Stanford, CA, USA
| | | | - Gregory Leeman
- School of Biosciences, University of Nottingham, Nottingham, UK
| | - Richard D Emes
- School of Veterinary Medicine and Science, University of Nottingham, Nottingham, UK.,Advanced Data Analysis Centre, University of Nottingham, Nottingham, UK
| | - Philippa Melamed
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Gillian R Bentley
- Department of Anthropology, Durham University, Durham, UK.,Wolfson Research Institute for Health and Wellbeing, Durham University, Durham, UK
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Silva-Caballero A, Ball HL, Kramer KL, Bentley GR. Sleep tight! Adolescent sleep quality across three distinct sleep ecologies. Evol Med Public Health 2023; 11:448-460. [PMID: 38044930 PMCID: PMC10693291 DOI: 10.1093/emph/eoad040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 10/05/2023] [Indexed: 12/05/2023] Open
Abstract
Background and objectives Good sleep quality, associated with few arousals, no daytime sleepiness and self-satisfaction with one's sleep, is pivotal for adolescent growth, maturation, cognition and overall health. This article aims to identify what ecological factors impact adolescent sleep quality across three distinct sleep ecologies representing a gradient of dense urbanity to small, rural environments with scarce artificial lighting and no Internet. Methodology We analyze variation of sleep efficiency, a quantitative measure of sleep quality-defined as the ratio of total time spent asleep to total time dedicated to sleep-in two agricultural indigenous populations and one post-industrial group in Mexico (Campeche = 44, Puebla = 51, Mexico City = 50, respectively). Data collection included actigraphy, sleep diaries, questionnaires, interviews and ethnographic observations. We fit linear models to examine sleep efficiency variation within and between groups. Results We found that sleep efficiency varied significantly across sites, being highest in Mexico City (88%) and lowest in Campeche (75%). We found that variation in sleep efficiency was significantly associated with nightly exposure to light and social sleep practices. Conclusions and implications Our findings point toward contextual cost-benefits of sleep disruption in adolescence. We highlight the need to prioritize research on adolescent sleep quality across distinct developmental ecologies and its impact on health to improve adolescent wellbeing through evidence-based health practices.
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Affiliation(s)
- Andrea Silva-Caballero
- Institute of Anthropological Research, National Autonomous University of Mexico, Mexico City, 04510, Mexico
- Department of Anthropology, Durham University, Durham, DH1 3LE, UK
| | - Helen L Ball
- Department of Anthropology, Durham University, Durham, DH1 3LE, UK
| | - Karen L Kramer
- Department of Anthropology, Univesity of Utah, Salt Lake City, RM 4625, USA
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Bar-Sadeh B, Pnueli L, Keestra S, Bentley GR, Melamed P. Srd5a1 is Differentially Regulated and Methylated During Prepubertal Development in the Ovary and Hypothalamus. J Endocr Soc 2023; 7:bvad108. [PMID: 37646011 PMCID: PMC10461783 DOI: 10.1210/jendso/bvad108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Indexed: 09/01/2023] Open
Abstract
5α-reductase-1 catalyzes production of various steroids, including neurosteroids. We reported previously that expression of its encoding gene, Srd5a1, drops in murine ovaries and hypothalamic preoptic area (POA) after early-life immune stress, seemingly contributing to delayed puberty and ovarian follicle depletion, and in the ovaries the first intron was more methylated at two CpGs. Here, we hypothesized that this CpG-containing locus comprises a methylation-sensitive transcriptional enhancer for Srd5a1. We found that ovarian Srd5a1 mRNA increased 8-fold and methylation of the same two CpGs decreased up to 75% between postnatal days 10 and 30. Estradiol (E2) levels rise during this prepubertal stage, and exposure of ovarian cells to E2 increased Srd5a1 expression. Chromatin immunoprecipitation in an ovarian cell line confirmed ESR1 binding to this differentially methylated genomic region and enrichment of the enhancer modification, H3K4me1. Targeting dCas9-DNMT3 to this locus increased CpG2 methylation 2.5-fold and abolished the Srd5a1 response to E2. In the POA, Srd5a1 mRNA levels decreased 70% between postnatal days 7 and 10 and then remained constant without correlation to CpG methylation levels. Srd5a1 mRNA levels did not respond to E2 in hypothalamic GT1-7 cells, even after dCas9-TET1 reduced CpG1 methylation by 50%. The neonatal drop in POA Srd5a1 expression occurs at a time of increasing glucocorticoids, and treatment of GT1-7 cells with dexamethasone reduced Srd5a1 mRNA levels; chromatin immunoprecipitation confirmed glucocorticoid receptor binding at the enhancer. Our findings on the tissue-specific regulation of Srd5a1 and its methylation-sensitive control by E2 in the ovaries illuminate epigenetic mechanisms underlying reproductive phenotypic variation that impact life-long health.
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Affiliation(s)
- Ben Bar-Sadeh
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Lilach Pnueli
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Sarai Keestra
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel
- Department of Anthropology, Durham University, Durham, DH1 3LE, UK
| | | | - Philippa Melamed
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel
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Sievert LL, Sharmeen T, Begum K, Muttukrishna S, Chowdhury O, Bentley GR. Frequency of Phytoestrogen Consumption and Symptoms at Midlife among Bangladeshis in Bangladesh and London. Nutrients 2023; 15:3676. [PMID: 37686708 PMCID: PMC10490262 DOI: 10.3390/nu15173676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 08/15/2023] [Accepted: 08/19/2023] [Indexed: 09/10/2023] Open
Abstract
There is a longstanding interest in the relationship between diet and hot flash symptoms during midlife, especially in whether phytoestrogens ease menopausal symptoms. The purpose of this study was to examine hot flashes, night sweats, trouble sleeping, and vaginal dryness in relation to the intake of foods rich in phytoestrogens among Bangladeshi women aged 35 to 59 years who were living either in Sylhet, Bangladesh (n = 157) or as migrants in London (n = 174). Consumption ranges for phytoestrogens were constructed from food frequencies. We hypothesized that diets rich in isoflavones, lignans, and coumestrol would be associated with lower symptom frequencies. However, adjusted logistic regression results showed that with each incremental increase in general phytoestrogen consumption (scale of 0 to 10), the likelihood of hot flashes increased by 1.4%. Each incremental increase in lignan consumption raised the likelihood of hot flashes by 1.6%. In contrast, the odds of vaginal dryness decreased by 2%, with each incremental increase in phytoestrogen and lignan consumption, and by 4%, with each incremental increase in isoflavone consumption. Night sweats and trouble sleeping were not associated with phytoestrogen intake in logistic regressions. Our findings add to the conflicting data on relationships between phytoestrogens and symptoms associated with menopause.
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Affiliation(s)
| | - Taniya Sharmeen
- Nuffield Department of Medicine, University of Oxford, Oxford OX3 7BN, UK
| | - Khurshida Begum
- Department of Anthropology, Durham University, Durham DH1 3LE, UK
| | - Shanthi Muttukrishna
- Department of Obstetrics and Gynecology, University College Cork, T12 E7WX Cork, Ireland
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Bar-Sadeh B, Amichai OE, Pnueli L, Begum K, Leeman G, Emes RD, Stöger R, Bentley GR, Melamed P. Epigenetic regulation of 5α reductase-1 underlies adaptive plasticity of reproductive function and pubertal timing. BMC Biol 2022; 20:11. [PMID: 34996447 PMCID: PMC8742331 DOI: 10.1186/s12915-021-01219-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 12/16/2021] [Indexed: 12/30/2022] Open
Abstract
Background Women facing increased energetic demands in childhood commonly have altered adult ovarian activity and shorter reproductive lifespan, possibly comprising a strategy to optimize reproductive success. Here, we sought to understand the mechanisms of early-life programming of reproductive function, by integrating analysis of reproductive tissues in an appropriate mouse model with methylation analysis of proxy tissue DNA in a well-characterized population of Bangladeshi migrants in the UK. Bangladeshi women whose childhood was in Bangladesh were found to have later pubertal onset and lower age-matched ovarian reserve than Bangladeshi women who grew-up in England. Subsequently, we aimed to explore the potential relevance to the altered reproductive phenotype of one of the genes that emerged from the screens. Results Of the genes associated with differential methylation in the Bangladeshi women whose childhood was in Bangladesh as compared to Bangladeshi women who grew up in the UK, 13 correlated with altered expression of the orthologous gene in the mouse model ovaries. These mice had delayed pubertal onset and a smaller ovarian reserve compared to controls. The most relevant of these genes for reproductive function appeared to be SRD5A1, which encodes the steroidogenic enzyme 5α reductase-1. SRD5A1 was more methylated at the same transcriptional enhancer in mice ovaries as in the women’s buccal DNA, and its expression was lower in the hypothalamus of the mice as well, suggesting a possible role in the central control of reproduction. The expression of Kiss1 and Gnrh was also lower in these mice compared to controls, and inhibition of 5α reductase-1 reduced Kiss1 and Gnrh mRNA levels and blocked GnRH release in GnRH neuronal cell cultures. Crucially, we show that inhibition of this enzyme in female mice in vivo delayed pubertal onset. Conclusions SRD5A1/5α reductase-1 responds epigenetically to the environment and its downregulation appears to alter the reproductive phenotype. These findings help to explain diversity in reproductive characteristics and how they are shaped by early-life environment and reveal novel pathways that might be targeted to mitigate health issues caused by life-history trade-offs. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01219-6.
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Affiliation(s)
- Ben Bar-Sadeh
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel
| | - Or E Amichai
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel
| | - Lilach Pnueli
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel
| | - Khurshida Begum
- Department of Anthropology, Durham University, Durham, DH1 3LE, UK
| | - Gregory Leeman
- School of Biosciences, University of Nottingham, Nottingham, LE12 5RD, UK
| | - Richard D Emes
- School of Veterinary Medicine and Sciences, University of Nottingham, Nottingham, LE12 5RD, UK
| | - Reinhard Stöger
- School of Biosciences, University of Nottingham, Nottingham, LE12 5RD, UK
| | | | - Philippa Melamed
- Faculty of Biology, Technion-Israel Institute of Technology, 32000, Haifa, Israel.
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Gorman J, Roberts CA, Newsham S, Bentley GR. Squatting, pelvic morphology and a reconsideration of childbirth difficulties. Evol Med Public Health 2022; 10:243-255. [PMID: 35663511 PMCID: PMC9154243 DOI: 10.1093/emph/eoac017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 04/19/2022] [Indexed: 11/14/2022] Open
Abstract
Abstract
Childbirth is commonly viewed as difficult in human females, encompassed by the ‘Obstetrical Dilemma’ (OD) described by early palaeoanthropologists as an evolved trade-off between a narrow pelvis necessitated by bipedalism and a large-brained fetal head. The OD has been challenged on several grounds. We add to these challenges by suggesting humans likely squatted regularly during routine tasks prior to the advent of farming societies and use of seats. We suggest that habitual squatting, together with taller stature and better nutrition of ancestral hunter-gatherers compared with later Neolithic and industrial counterparts, obviated an OD. Instead, difficulties with parturition may have arisen much later in our history, accompanying permanent settlements, poorer nutrition, greater infectious disease loads and negligible squatting in daily life. We discuss bioarchaeological and contemporary data that support these viewpoints, suggest ways in which this hypothesis might be tested further and consider its implications for obstetrical practice.
Lay Summary
Human childbirth is viewed as universally difficult. Evidence from physical therapies/engineering and studies of living and ancestral humans illustrates habitual squatting widens the pelvis and could improve childbirth outcomes. Obstetrical difficulties emerged late in prehistory accompanying settled agriculture, poorer nutrition and less squatting. Specific physical exercises could improve obstetrical practice.
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Affiliation(s)
- John Gorman
- Independent Scholar , Greenhead, Brampton, Northumberland CA8 7HX, UK
| | - Charlotte A Roberts
- Department of Archaeology, Durham University , Dawson Building, South Road , Durham DH1 3LE, UK
| | - Sally Newsham
- Department of Gynaecology, North Cumbria Integrated Care NHS Foundation Trust , Cumbria CA2 7HY, UK
| | - Gillian R Bentley
- Department of Anthropology, Durham University , Dawson Building, South Road , Durham DH1 3LE, UK
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Begum K, Cooper GD, Akhter N, Nahar P, Kasim A, Bentley GR. Early life, life course and gender influences on levels of C-reactive protein among migrant Bangladeshis in the UK. Evol Med Public Health 2022; 10:21-35. [PMID: 35035976 PMCID: PMC8754477 DOI: 10.1093/emph/eoab041] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Accepted: 11/18/2021] [Indexed: 11/14/2022] Open
Abstract
Background and objectives Humans co-evolved with pathogens, especially helminths, that educate the immune system during development and lower inflammatory responses. The absence of such stimuli in industrialized countries is associated with higher baseline levels of C-reactive protein (CRP) among adults who appear at greater risk for inflammatory disorders. This cross-sectional study examined effects of early life development on salivary CRP levels in 452 British-Bangladeshis who spent varying periods growing up in Bangladesh or UK. We also analyzed how gender and central obesity modulate effects on CRP. We hypothesized that: (i) first-generation Bangladeshis with higher childhood exposure to pathogens would have chronically lower CRP levels than second-generation British-Bangladeshis; (ii) effects would be greater with early childhoods in Bangladesh; (iii) effects by gender would differ; and (iv) increasing obesity would mitigate early life effects. Methodology Saliva samples were assayed for CRP using ELISAs, and anthropometric data collected. Participants completed questionnaires about demographic, socioeconomic, lifestyle and health histories. Data were analyzed using multiple linear regression. Results First-generation migrants who spent early childhoods in mostly rural, unhygienic areas, and moved to UK after age 8, had lower salivary CRP compared to the second-generation. Effects differed by gender, while waist circumference predicted higher CRP levels. CRP increased with years in UK, alongside growing obesity. Conclusions and implications Our study supports the hypothesis that pathogen exposure in early life lowers inflammatory responses in adults. However, protective effects differed by gender and can be eroded by growing obesity across the life course which elevates risks for other inflammatory disorders. Lay Summary: Migrants to the UK who spent early childhoods in less hygienic environments in Bangladesh that help to educate their immune systems had lower levels of the inflammatory marker, C-reactive protein (CRP) compared to migrants who grew up in UK. Both gender and increasing obesity were associated with increased levels of CRP.
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Affiliation(s)
- Khurshida Begum
- Department of Anthropology, Durham University, Dawson Building, South Road, Durham DH1 3LE, UK
| | - Gillian D Cooper
- Department of Anthropology, Durham University, Dawson Building, South Road, Durham DH1 3LE, UK
| | - Nasima Akhter
- Department of Anthropology, Durham University, Dawson Building, South Road, Durham DH1 3LE, UK
| | - Papreen Nahar
- Department of Anthropology, Durham University, Dawson Building, South Road, Durham DH1 3LE, UK
- Department of Global Health and Infection, University of Sussex, BSMS Teaching Building, Brighton BN1 9PX, East Sussex, UK
| | - Adetayo Kasim
- Department of Anthropology, Durham University, Dawson Building, South Road, Durham DH1 3LE, UK
- Durham Research Methods Centre, Faculty of Social Sciences & Health, Durham University, Arthur Holmes Building, Durham DH1 3LE, UK
- UCB Pharmaceuticals, 216 Bath Road, Slough SL1 3WE, UK
| | - Gillian R Bentley
- Department of Anthropology, Durham University, Dawson Building, South Road, Durham DH1 3LE, UK
- Corresponding author. Department of Anthropology, Durham University, Dawson Building, South Road, Durham DH1 3LE, UK. Tel: 011 44 191 334 1114; E-mail:
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Bentley GR, Bogin BA, Bar-Sadeh B, Stöger R, Melamed P. Reply to: Timing of puberty - body size or reproductive optimization? Nat Rev Endocrinol 2021; 17:573-574. [PMID: 33958767 DOI: 10.1038/s41574-021-00502-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
| | - Barry A Bogin
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Ben Bar-Sadeh
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Reinhard Stöger
- School of Biosciences, University of Nottingham, Nottingham, UK
| | - Philippa Melamed
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel.
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Chaney C, Begum K, Núñez-de la Mora A, Sievert LL, Muttukrishna S, Harries V, Sharmeen T, Murphy L, Gunu R, Chowdhury O, Bentley GR. No impact of developmental conditions on serum estradiol levels among Bangladeshi women in the UK and Bangladesh. Am J Hum Biol 2021; 34:e23631. [PMID: 34174012 DOI: 10.1002/ajhb.23631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 06/09/2021] [Accepted: 06/14/2021] [Indexed: 11/10/2022] Open
Abstract
INTRODUCTION While many aspects of female ovarian function respond to environmental stressors, estradiol (E2) appears less sensitive to stressors than progesterone, except under extreme ecological conditions. However, earlier studies relied on saliva samples, considered less sensitive than blood. Here, we investigated E2 variation among 177 Bangladeshi and UK white women, aged 35-59, using single serum samples. Bangladeshi women either grew up in Sylhet, Bangladesh (exposed to poor sanitation, limited health care, and higher pathogen loads but not poor energy availability), or in the UK. METHODS We collected samples on days 4-6 of the menstrual cycle in menstruating women and on any day for post-menopausal women. Participants included: (i) Bangladeshi sedentees (n = 36), (ii) Bangladeshis who migrated to the UK as adults (n = 52), (iii) Bangladeshis who migrated as children (n = 40), and (iv) UK white women matched for neighborhood residence to the migrants (n = 49). Serum was obtained by venipuncture and analyzed using electrochemiluminescence. We collected anthropometrics and supplementary sociodemographic and reproductive data through questionnaires. We analyzed the data using multivariate regression. RESULTS E2 levels did not differ between migrant groups after controlling for age, BMI, physical activity, psychosocial stress, parity, and time since last birth (parous women). Paralleling results from salivary E2, serum E2 did not differ among women who experienced varying developmental conditions. CONCLUSION Our results reinforce the hypothesis that E2 levels are stable under challenging environmental conditions. Interpopulation variation may only arise under chronic conditions of extreme nutritional scarcity, energy expenditure, and/or high disease burdens.
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Affiliation(s)
- Carlye Chaney
- Department of Anthropology, Yale University, New Haven, Connecticut, USA
| | | | | | - Lynnette L Sievert
- Department of Anthropology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Shanthi Muttukrishna
- Anu Research Centre, Department of Obstetrics and Gynaecology, University College Cork, Cork, Republic of Ireland
| | - Victoria Harries
- Department of Anthropology, Yale University, New Haven, Connecticut, USA
| | - Taniya Sharmeen
- Reading School of Pharmacy, University of Reading, Reading, UK
| | - Lorna Murphy
- School of Public Health, University of Massachusetts, Amherst, Massachusetts, USA
| | - Richard Gunu
- Institute for Women's Health, University College London, London, UK
| | - Osul Chowdhury
- Department of Microbiology, Parkview Medical College, Sylhet, Bangladesh
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Smith N, Sievert LL, Muttukrishna S, Begum K, Murphy L, Sharmeen T, Gunu R, Chowdhury O, Bentley GR. Mismatch: a comparative study of vitamin D status in British-Bangladeshi migrants. Evol Med Public Health 2021; 9:164-173. [PMID: 33763230 PMCID: PMC7928960 DOI: 10.1093/emph/eoab001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Accepted: 01/05/2021] [Indexed: 11/17/2022]
Abstract
Background and objectives Low levels of vitamin D among dark-skinned migrants to northern latitudes and increased risks for associated pathologies illustrate an evolutionary mismatch between an environment of high ultraviolet (UV) radiation to which such migrants are adapted and the low UV environment to which they migrate. Recently, low levels of vitamin D have also been associated with higher risks for contracting COVID-19. South Asians in the UK have higher risk for low vitamin D levels. In this study, we assessed vitamin D status of British-Bangladeshi migrants compared with white British residents and Bangladeshis still living in Bangladesh (‘sedentees’). Methodology The cross-sectional study compared serum vitamin D levels among 149 women aged 35–59, comprising British-Bangladeshi migrants (n = 50), white British neighbors (n = 54) and Bangladeshi sedentees (n = 45). Analyses comprised multivariate models to assess serum levels of 25-hydroxyvitamin D (25(OH)D), and associations with anthropometric, lifestyle, health and migration factors. Results Vitamin D levels in Bangladeshi migrants were very low: mean 25(OH)D = 32.2 nmol/L ± 13.0, with 29% of migrants classified as deficient (<25 nmol/L) and 94% deficient or insufficient (≤50 nmol/L). Mean levels of vitamin D were significantly lower among British-Bangladeshis compared with Bangladeshi sedentees (50.9 nmol/L ± 13.3, P < 0.001) and were also lower than in white British women (55.3 nmol/L ± 20.9). Lower levels of vitamin D were associated with increased body mass index and low iron status. Conclusions and implications We conclude that lower exposure to sunlight in the UK reduces vitamin D levels in Bangladeshi migrants. Recommending supplements could prevent potentially adverse health outcomes associated with vitamin D deficiency. Lay Summary Vitamin D deficiency is one example of mismatch between an evolved trait and novel environments. Here we compare vitamin D status of dark-skinned British-Bangladeshi migrants in the UK to Bangladeshis in Bangladesh and white British individuals. Migrants had lower levels of vitamin D and are at risk for associated pathologies.
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Affiliation(s)
- Nicholas Smith
- General Medicine, Gateshead Health NHS Foundation Trust, Gateshead, UK.,Department of Anthropology, Durham University, Durham, UK
| | | | - Shanthi Muttukrishna
- Department of Obstetrics and Gynaecology, ANU Research Centre, University of Cork, Cork, Ireland
| | | | - Lorna Murphy
- Department of Anthropology, UMass Amherst, Amherst, MA, USA
| | | | - Richard Gunu
- Institute for Women's Health, University College London, London, UK
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Bar-Sadeh B, Rudnizky S, Pnueli L, Bentley GR, Stöger R, Kaplan A, Melamed P. Unravelling the role of epigenetics in reproductive adaptations to early-life environment. Nat Rev Endocrinol 2020; 16:519-533. [PMID: 32620937 DOI: 10.1038/s41574-020-0370-8] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/11/2020] [Indexed: 11/08/2022]
Abstract
Reproductive function adjusts in response to environmental conditions in order to optimize success. In humans, this plasticity includes age of pubertal onset, hormone levels and age at menopause. These reproductive characteristics vary across populations with distinct lifestyles and following specific childhood events, and point to a role for the early-life environment in shaping adult reproductive trajectories. Epigenetic mechanisms respond to external signals, exert long-term effects on gene expression and have been shown in animal and cellular studies to regulate normal reproductive function, strongly implicating their role in these adaptations. Moreover, human cohort data have revealed differential DNA methylation signatures in proxy tissues that are associated with reproductive phenotypic variation, although the cause-effect relationships are difficult to discern, calling for additional complementary approaches to establish functionality. In this Review, we summarize how adult reproductive function can be shaped by childhood events. We discuss why the influence of the childhood environment on adult reproductive function is an important consideration in understanding how reproduction is regulated and necessitates consideration by clinicians treating women with diverse life histories. The resolution of the molecular mechanisms responsible for human reproductive plasticity could also lead to new approaches for intervention by targeting these epigenetic modifications.
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Affiliation(s)
- Ben Bar-Sadeh
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Sergei Rudnizky
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Lilach Pnueli
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | | | - Reinhard Stöger
- Department of Biological Sciences, University of Nottingham, Nottingham, UK
| | - Ariel Kaplan
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Philippa Melamed
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel.
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Bentley GR. Don't blame the BAME: Ethnic and structural inequalities in susceptibilities to COVID-19. Am J Hum Biol 2020; 32:e23478. [PMID: 32677326 PMCID: PMC7404609 DOI: 10.1002/ajhb.23478] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/30/2020] [Accepted: 07/01/2020] [Indexed: 12/20/2022] Open
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Keestra SM, Bentley GR, Núñez-de la Mora A, Houghton LC, Wilson H, Vázquez-Vázquez A, Cooper GD, Dickinson F, Griffiths P, Bogin BA, Varela-Silva MI. The timing of adrenarche in Maya girls, Merida, Mexico. Am J Hum Biol 2020; 33:e23465. [PMID: 32643208 PMCID: PMC8264844 DOI: 10.1002/ajhb.23465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 11/17/2022] Open
Abstract
Background Adrenarche involves maturation of the hypothalamic‐pituitary‐adrenal axis and increased production of dehydroepiandrosterone and its sulfate ester, dehydroepiandrosterone‐sulfate (DHEA‐S). It occurs at ages 6 to 8 in industrialized populations, marking the transition from childhood to juvenility and cognitive development at middle childhood. Studies in subsistence level populations indicate a later age (8‐9) for adrenarche, but only two such studies currently exist for comparison. Aims To investigate adrenarcheal age among Maya girls and its association with body composition and dietary variables. We hypothesized adrenarche would occur earlier given the current dual burden of nutrition in Mexico. Materials and Methods 25 Maya girls aged 7 to 9 from Merida, Mexico using ELISAs to measure salivary DHEA‐S, standard anthropometry for height, weight, and skinfolds, bioelectrical impedance for body composition variables, as well as a food frequency questionnaire for dietary information. Results Our hypothesis was rejected—adrenarche occurred close to 9 years. While no measures of body composition were significantly associated with adrenarcheal status, girls eating meat and dairy products more frequently had significantly higher DHEA‐S levels. Discussion Like other populations living in ecologically challenging environments, adrenarche occurred relatively late among Maya girls. Adrenarche has been linked to measures of body composition, particularly, the adiposity or body mass index rebound, but no relevant anthropometric measures were associated, possibly because of the small sample. Conclusion Further studies are required to illuminate how adrenarcheal variation relates to developmental plasticity, body composition, pubertal progression, and animal product consumption in other transitional populations.
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Affiliation(s)
| | | | | | | | | | | | | | - Federico Dickinson
- Department of Human Ecology, Centre for Research and Advanced Studies of the National Polytechnic Institute Cinvestav (Merida), Mexico
| | - Paula Griffiths
- School of Sport, Exercise and Health Sciences, Loughborough University, UK
| | - Barry A Bogin
- School of Sport, Exercise and Health Sciences, Loughborough University, UK.,UCSD/Salk Center for Academic Research and Training in Anthropogeny (CARTA), USA
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Sievert LL, Bentley GR. Meetings of the Human Biology Association, 2019. Evol Anthropol 2019; 28:112-113. [DOI: 10.1002/evan.21781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 05/06/2019] [Indexed: 11/08/2022]
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Magid K, Chatterton RT, Ahamed FU, Bentley GR. Author Correction: Childhood ecology influences salivary testosterone, pubertal age and stature of Bangladeshi UK migrant men. Nat Ecol Evol 2018; 2:1331. [PMID: 29967487 DOI: 10.1038/s41559-018-0620-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In the version of this Article originally published, the units for the 'Weight' column in Table 1 were incorrect; they should have been kg. This has now been corrected.
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Affiliation(s)
- Kesson Magid
- Department of Anthropology, University of Durham, Durham, UK.
| | - Robert T Chatterton
- Department of Obstetrics and Gynecology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.,Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.,Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Farid Uddin Ahamed
- Department of Anthropology, University of Chittagong, Chittagong, Bangladesh
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Bentley GR. Editorial comment: Pre-eclampsia. Evol Med Public Health 2018; 2018:295-296. [PMID: 30595840 PMCID: PMC6304805 DOI: 10.1093/emph/eoy030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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18
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Read AF, Bentley GR, Haig D. George C Williams Prize 2015. Evol Med Public Health 2016; 2016:212-3. [PMID: 27378797 PMCID: PMC4944834 DOI: 10.1093/emph/eow017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/16/2016] [Accepted: 05/17/2016] [Indexed: 11/13/2022]
Affiliation(s)
- Andrew F Read
- Center for Infectious Disease Dynamics, Departments of Biology and Entomology, Pennsylvania State University, University Park, PA 16802, USA
| | - Gillian R Bentley
- Department of Anthropology and Wolfson Research Institute for Health and Wellbeing, Durham University, Durham, UK
| | - David Haig
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA
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Dhanoya T, Sievert LL, Muttukrishna S, Begum K, Sharmeen T, Kasim A, Chowdhury O, Bentley GR. Hot flushes and reproductive hormone levels during the menopausal transition. Maturitas 2016; 89:43-51. [DOI: 10.1016/j.maturitas.2016.03.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 03/20/2016] [Accepted: 03/22/2016] [Indexed: 12/18/2022]
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Begum K, Muttukrishna S, Sievert LL, Sharmeen T, Murphy L, Chowdhury O, Kasim A, Gunu R, Bentley GR. Ethnicity or environment: effects of migration on ovarian reserve among Bangladeshi women in the United Kingdom. Fertil Steril 2015; 105:744-754.e1. [PMID: 26706133 DOI: 10.1016/j.fertnstert.2015.11.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 10/24/2015] [Accepted: 11/16/2015] [Indexed: 12/15/2022]
Abstract
OBJECTIVE To assess whether the quality of early childhood environments among different groups of Bangladeshi women, including migrants to the United Kingdom (UK), contributes to variation in ovarian reserve and the rate of reproductive aging in later life. DESIGN Cross-sectional study. SETTING Not applicable. PATIENT(S) A total of 179 healthy women volunteers aged 35-59 years were divided into four groups: [1] 36 Bangladeshis living in Sylhet, Bangladesh; [2] 53 Bangladeshis who migrated to the UK as adults; [3] 40 Bangladeshis who migrated to the UK as children aged 0-16 years; and [4] a reference group of 50 women of European origin living in London. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Levels of serum antimüllerian hormone, inhibin B, FSH, and E2, and anthropometrics derived from biomarkers; reproductive, demographic, and health variables from structured questionnaires. RESULT(S) Bangladeshi migrants who moved to the UK as children and European women had a highly significantly larger, age-related ovarian reserve compared with migrant Bangladeshis who had moved to the UK as adults or Bangladeshi women still living in Bangladesh. There were no other significant covariates in the model aside from age and menopausal status. CONCLUSION(S) The study points to the importance of childhood development in considering variation in ovarian reserve across different ethnic groups. Clinical studies and research in assisted reproductive technology have emphasized the role of genes or race in determining inter-population variation in ovarian reserve. Early life developmental factors should be given due consideration when evaluating inter-group differences in response to assisted reproductive technology.
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Affiliation(s)
- Khurshida Begum
- Department of Anthropology, University College London, London, United Kingdom
| | - Shanthi Muttukrishna
- Anu Research Centre, Department of Obstetrics and Gynaecology, University College Cork, Cork, Republic of Ireland
| | | | - Taniya Sharmeen
- Department of Anthropology, University College London, London, United Kingdom
| | - Lorna Murphy
- School of Public Health, University of Massachusetts, Amherst, Massachusetts
| | | | - Adetayo Kasim
- Wolfson Research Institute for Health and Wellbeing, Durham University, Durham, United Kingdom
| | - Richard Gunu
- Institute for Women's Health, University College London, London, United Kingdom
| | - Gillian R Bentley
- Department of Anthropology and Wolfson Research Institute for Health and Wellbeing, Durham University, Durham, United Kingdom.
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Houghton LC, Cooper GD, Bentley GR, Booth M, Chowdhury OA, Troisi R, Ziegler RG, Hoover RN, Katki HA. A migrant study of pubertal timing and tempo in British-Bangladeshi girls at varying risk for breast cancer. Breast Cancer Res 2014; 16:469. [PMID: 25398700 PMCID: PMC4303203 DOI: 10.1186/s13058-014-0469-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 10/20/2014] [Indexed: 11/22/2022] Open
Abstract
Introduction Earlier menarche is related to subsequent breast cancer risk, yet international differences in the age and tempo of other pubertal milestones and their relationships with body mass index (BMI) are not firmly established in populations at differing risk for breast cancer. We compared age and tempo of adrenarche, thelarche, pubarche, and menarche in a migrant study of Bangladeshi girls to the United Kingdom (UK) and assessed whether differences by migration were explained by differences in BMI. Methods Included were groups of Bangladeshi (n =168), British-Bangladeshi (n =174) and white British (n =54) girls, aged 5 to 16 years. Interviewer-administered questionnaires obtained pubertal staging; height and weight were measured. Salivary dehydroepiandrosterone-sulfate concentrations >400 pg/ml defined adrenarche. Median ages of pubertal milestones and hazard ratios (HR) with 95% confidence intervals (CI) were estimated from Weibull survival models. Results In all three groups, adrenarche occurred earliest, followed by thelarche, pubarche, and finally menarche. Neither median age at adrenarche (Bangladeshi = 7.2, British-Bangladeshi = 7.4, white British = 7.1; P-trend = 0.70) nor at menarche (Bangladeshi = 12.5, British-Bangladeshi = 12.1, white British = 12.6; P-trend = 0.70) differed across groups. In contrast, median age at thelarche (Bangladeshi = 10.7, British-Bangladeshi = 9.6, white British = 8.7; P-trend <0.01) occurred earlier among girls living in the UK. Compared with Bangladeshi girls, HRs (95% CI) for earlier thelarche were 1.6 (1.1 to 2.4) for British-Bangladeshi girls and 2.6 (1.5 to 4.4) for white British girls (P-trend <0.01), but were attenuated after adjustment for BMI (British-Bangladeshi = 1.1 (0.7 to 1.8), white British = 1.7(1.0 to 3.1); P-trend =0.20). Conclusions Thelarche occurred earlier, but puberty progressed slower with increasing exposure to the UK environment; differences were partially explained by greater BMI. The growth environment might account for much of the ethnic differences in pubertal development observed across and within countries. Electronic supplementary material The online version of this article (doi:10.1186/s13058-014-0469-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Lauren C Houghton
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Gillian D Cooper
- Department of Anthropology and Wolfson Research Institute for Health and Wellbeing, Durham University, Durham, UK.
| | - Gillian R Bentley
- Department of Anthropology and Wolfson Research Institute for Health and Wellbeing, Durham University, Durham, UK.
| | - Mark Booth
- School for Medicine, Pharmacy and Health, Durham University, Durham, UK.
| | | | - Rebecca Troisi
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Regina G Ziegler
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Robert N Hoover
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Hormuzd A Katki
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
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Abstract
OBJECTIVE The aims of this study were (1) to document the extent of variability in physiological aspects of reproductive aging; (2) to outline those areas where more work is needed to expand our knowledge of this variability; (3) to outline available biomarkers that can be used to measure aspects of reproductive aging, such as ovarian reserve and declining hormone levels; and (4) to note potential problems with the use of these biomarkers in cross-cultural settings. DESIGN Literature review of English and French publications using PubMed with no date restrictions. RESULTS Substantial variability exists in both cultural and physiological aspects of reproductive aging and menopause. However, the extent of variability across populations for many areas of reproductive aging needs better documentation as well as explanation of sources of this variability. Several biomarkers exist for use in cross-cultural research, including ovarian characteristics such as ovarian volume, ovarian reserve, follicular development, and atresia, and levels of hormones such as follicle-stimulating hormone, inhibin B, and anti-mullerian hormone. CONCLUSION We urge that further work be undertaken to evaluate and describe variability in physiological aspects of reproductive aging in cross-cultural settings. Some problems exist in the use of biomarkers to record this variability, particularly in remote settings with few logistical resources.
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Affiliation(s)
- Gillian R Bentley
- Department of Anthropology and Wolfson Research Institute, Durham University, Durham, England, UK.
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Abstract
BACKGROUND Average profiles of salivary progesterone in women vary significantly at the inter- and intrapopulation level as a function of age and acute energetic conditions related to energy intake, energy expenditure, or a combination of both. In addition to acute stressors, baseline progesterone levels differ among populations. The causes of such chronic differences are not well understood, but it has been hypothesised that they may result from varying tempos of growth and maturation and, by implication, from diverse environmental conditions encountered during childhood and adolescence. METHODS AND FINDINGS To test this hypothesis, we conducted a migrant study among first- and second-generation Bangladeshi women aged 19-39 who migrated to London, UK at different points in the life-course, women still resident in Bangladesh, and women of European descent living in neighbourhoods similar to those of the migrants in London (total n = 227). Data collected included saliva samples for radioimmunoassay of progesterone, anthropometrics, and information from questionnaires on diet, lifestyle, and health. Results from multiple linear regression, controlled for anthropometric and reproductive variables, show that women who spend their childhood in conditions of low energy expenditure, stable energy intake, good sanitation, low immune challenges, and good health care in the UK have up to 103% higher levels of salivary progesterone and an earlier maturation than women who develop in less optimal conditions in Sylhet, Bangladesh (F9,178 = 5.05, p < 0.001, standard error of the mean = 0.32; adjusted R(2) = 0.16). Our results point to the period prior to puberty as a sensitive phase when changes in environmental conditions positively impact developmental tempos such as menarcheal age (F2,81 = 3.21, p = 0.03) and patterns of ovarian function as measured using salivary progesterone (F2,81 = 3.14, p = 0.04). CONCLUSIONS This research demonstrates that human females use an extended period of the life cycle prior to reproductive maturation to monitor their environment and to modulate reproductive steroid levels in accordance with projected conditions they might encounter as adults. Given the prolonged investment of human pregnancy and lactation, such plasticity (extending beyond any intrauterine programming) enables a more flexible and finely tuned adjustment to the potential constraints or opportunities of the later adult environment. This research is the first, to our knowledge, to demonstrate a postuterine developmental component to variation in reproductive steroid levels in women.
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Núñez-de la Mora A, Chatterton RT, Mateo ET, Jesmin F, Bentley GR. Effect of chewing betel nut on measurements of salivary progesterone and estradiol. Am J Phys Anthropol 2007; 132:311-5. [PMID: 17133435 DOI: 10.1002/ajpa.20513] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The measurement of steroids in saliva is both simple and non-invasive and has been widely used in field and clinical-based research. The observance of particular cultural practices by some populations, however, may hamper accurate hormonal analyses. The present study evaluated the effects of one such practice-the chewing of betel nut-on the accurate measurement of salivary progesterone and estradiol. A time series experiment was conducted among Bangladeshi women who are regular users of betel nut. Salivary steroids were analyzed by radioimmunoassay in samples collected prior to and then 30, 60, 120, and 240 min following betel quid use. Results show no significant difference between basal steroid levels and those obtained 60, 120, and 240 min after chewing betel nut. We conclude that with specific collection protocols that take into account time since chewing, salivary steroid analyses can be undertaken in populations among whom the practice of chewing betel nut is endemic.
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Abstract
This study evaluated the effects of socio-economic variables and migration history on the prevalence of betel nut and smokeless tobacco use in both UK- and Bangladeshi born migrant women resident in London. No significant difference in betel nut use prevalence was found among women of different generations. However, in all groups betel nut users were significantly older and less educated than non-users. Among first generation women there was no effect of either length of time living in the UK or age at migration on use of betel nut, even after controlling for current age. No significant differences in prevalence use due to language spoken, occupation, marital status or borough of residence in London were found. We conclude that, although there are some indications of a change in behavior among younger individuals, betel nut chewing is a practice very much present among Bangladeshi women born and brought up in a bicultural context.
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Núñez-De La Mora A, Bentley GR, Choudhury OA, Napolitano DA, Chatterton RT. The impact of developmental conditions on adult salivary estradiol levels: Why this differs from progesterone? Am J Hum Biol 2007; 20:2-14. [DOI: 10.1002/ajhb.20698] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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Cordaux R, Saha N, Bentley GR, Aunger R, Sirajuddin SM, Stoneking M. Mitochondrial DNA analysis reveals diverse histories of tribal populations from India. Eur J Hum Genet 2003; 11:253-64. [PMID: 12678055 DOI: 10.1038/sj.ejhg.5200949] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We analyzed 370 bp of the first hypervariable region of the mitochondrial DNA (mtDNA) control region in 752 individuals from 17 tribal and four nontribal groups from the Indian subcontinent, to address questions concerning the origins, genetic structure and relationships of these groups. Southern Indian tribes showed reduced diversity and large genetic distances, both among themselves and when compared with other groups, and no signal of prehistoric demographic expansions. These results probably reflect enhanced genetic drift because of small population sizes and/or bottlenecks in these groups. By contrast, northern groups exhibited more diversity and signals of prehistoric demographic expansions. Phylogenetic analyses revealed that southern and northern groups (except northeastern ones) have related mtDNA sequences albeit at different frequencies, further supporting the larger impact of drift on the genetic structure of southern groups. The Indian mtDNA gene pool appears to be more closely related to the east Eurasian gene pool (including central, east and southeast Asian populations) than the west Eurasian one (including European and Caucasian populations). Within India, northeastern tribes are quite distinct from other groups; they are more closely related to east Asians than to other Indians. This is consistent with linguistic evidence in that these populations speak Tibeto-Burman languages of east Asian origin. Otherwise, analyses of molecular variance suggested that caste and tribal groups are genetically similar with respect to mtDNA variation.
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Affiliation(s)
- Richard Cordaux
- Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.
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Ellison PT, Bribiescas RG, Bentley GR, Campbell BC, Lipson SF, Panter-Brick C, Hill K. Population variation in age-related decline in male salivary testosterone. Hum Reprod 2002; 17:3251-3. [PMID: 12456632 DOI: 10.1093/humrep/17.12.3251] [Citation(s) in RCA: 143] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Age-related declines in free and bioavailable testosterone are frequently reported for Western populations, but interpopulation variation in this pattern has not previously been investigated. METHODS Salivary testosterone was measured using a consistently applied protocol on morning samples collected from men in four populations (USA, Congo, Nepal, and Paraguay) representing different geographical, ecological, and cultural settings. RESULTS Mean testosterone levels varied significantly between the four populations. The mean testosterone differences between populations were greatest for young men (aged 15-30 years) and insignificant for older men (aged 45-60 years). The slope of age-related decline in testosterone was significant in the USA and Congolese participants, but not in the Nepalese or Paraguayan participants. CONCLUSIONS Age patterns of testosterone decline vary between populations primarily as a result of variation in the peak levels attained in young adulthood. The potential consequences of this variation for other aspects of male health deserve investigation.
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Affiliation(s)
- Peter T Ellison
- Department of Anthropology, Harvard University, Cambridge, MA, USA.
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Vitzthum VJ, Bentley GR, Spielvogel H, Caceres E, Thornburg J, Jones L, Shore S, Hodges KR, Chatterton RT. Salivary progesterone levels and rate of ovulation are significantly lower in poorer than in better-off urban-dwelling Bolivian women. Hum Reprod 2002; 17:1906-13. [PMID: 12093859 DOI: 10.1093/humrep/17.7.1906] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Agriculturalists in less-developed countries (LDC) have lower progesterone levels than urban industrialized populations. However, it is unknown if urban LDC populations are also relatively lower. We tested whether urban Bolivia samples-poorer (Bol-p) and better-off (Bol-b)-have lower progesterone than a Chicago (USA) sample, and whether progesterone and rate of ovulation are lower in Bol-p than in Bol-b. METHODS Serial salivary samples collected from Bolivians, screened according to strict exclusion criteria during two complete menstrual cycles, were radioimmunoassayed for progesterone; anthropometrics were collected at mid-follicular and mid-luteal phases. RESULTS Progesterone levels are lower in the Bolivia samples, and higher in the Bol-b than Bol-p; ovulation rate is greater in Bol-b than Bol-p. For only ovulatory cycles, mean-follicular-P (pmol/l), mean-luteal-P (pmol/l), and mean-peak-P (pmol/l) are respectively 65, 142 and 208 in Bol-p; 76, 167 and 232 in Bol-b; and 96, 240 and 330 in Chicago. Principal components representing body-size and progesterone level are positively correlated (r = 0.404, P = 0.005). CONCLUSIONS Progesterone levels appear to be influenced by chronic and acute ecological conditions, evidenced by the association with body-size and the probability of ovulation respectively. These findings have implications for understanding cancer aetiology, developing population-appropriate hormonal contraceptives, and modelling the evolution and functioning of the reproductive system.
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Affiliation(s)
- Virginia J Vitzthum
- Institute for Primary and Preventative Health Care, and Department of Anthropology, Binghamton University (SUNY), Binghamton, NY 13901, USA.
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Bentley GR. Women’s Bodies, Women’s Worries: Health and Family Planning in a Vietnamese Rural Community. Soc Sci Med 2000. [DOI: 10.1016/s0277-9536(00)00089-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Clark VJ, Sivendren S, Saha N, Bentley GR, Aunger R, Sirajuddin SM, Stoneking M. The 9-bp deletion between the mitochondrial lysine tRNA and COII genes in tribal populations of India. Hum Biol 2000; 72:273-85. [PMID: 10803659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
A 9-base-pair (bp) deletion located between the lysine tRNA (MTTK) and COII (MTCOX*2) genes in the human mitochondrial genome is a valuable marker for tracing population relationships. Previous research has shown that the 9-bp deletion is associated with two major clusters of control region sequences; one occurs in sub-Saharan Africa, while the other is associated with Asian populations and populations of Asian origin. We surveyed 898 individuals from 16 tribal populations in India and found 6 individuals with the 9-bp deletion. Sequences of the first hypervariable segment (HV1) of the mtDNA control region from these 9-bp deletion-bearing mtDNAs were compared to those previously reported from Asian and African populations. Phylogenetic analysis indicates three distinct clusters of tribal Indian 9-bp deletion mtDNA types. One cluster, found in northeast India, includes southeast Asian and Indonesian mtDNA types. The remaining two clusters appear to have unique origins in southern India. These data provide further evidence of past migrations from Asia into the northeast corner of the Indian subcontinent.
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Affiliation(s)
- V J Clark
- Department of Anthropology, Pennsylvania State University, University Park, USA
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Lu Y, Bentley GR, Gann PH, Hodges KR, Chatterton RT. Salivary estradiol and progesterone levels in conception and nonconception cycles in women: evaluation of a new assay for salivary estradiol. Fertil Steril 1999; 71:863-8. [PMID: 10231047 DOI: 10.1016/s0015-0282(99)00093-x] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To determine the usefulness of salivary E2 and progesterone for noninvasive assessment of ovarian function. DESIGN Prospective study of salivary hormone levels in women planning a pregnancy. SETTING Department of Obstetrics and Gynecology at Northwestern University Medical School in Chicago, Illinois. PATIENT(S) Fourteen women aged 23-39 years with regular menstrual cycles who were planning a pregnancy. INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) Salivary estradiol and progesterone concentrations. RESULT(S) The sensitivity of the E2 assay is 2.0 pmol/L; the interassay coefficient of variation was 5.2% (mean value 17 pmol/L). Recovery of E2 added to saliva was 106%. The correlation with simultaneous serum samples was 0.71. Menstrual cycle patterns contained a preovulatory depression and a midcycle surge. By comparison with nonconception cycles, the luteal phases of conception cycles had significantly elevated salivary E2 within the first 5 days after ovulation. Salivary progesterone was significantly elevated but not until 10 days after ovulation. CONCLUSION(S) Salivary measurements of E2 and progesterone can be used as noninvasive methods for assessment of ovarian function. Salivary specimens can be collected at home and brought to the laboratory for analysis, obviating the need for frequent phlebotomy. The sensitivity and precision of the salivary E2 assay make it comparable with assays of serum E2 for assessing changes in hormone levels.
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Affiliation(s)
- Y Lu
- Department of Obstetrics and Gynecology, Northwestern University Medical School, Chicago, Illinois 60611, USA
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Abstract
Many agricultural populations are subject to chronic or seasonal undernutrition, reproductive women and children often being most vulnerable. This paper presents quantitative and qualitative data on food consumption, food distribution practices, food taboos, garden sizes and work effort to show how Lese horticulturalist women living in the Ituri Forest of northeast Democratic Republic of Congo attempt to alleviate nutritional stress. The Lese experience an annual hunger season when approximately one quarter of the population suffer from energy deficiency. Nutritional intake is also compromised by a complex system of food taboos against meat from wild forest animals. Anthropometric data collected over several years suggest that Lese women suffer from nutritional stress more than men during the hunger season. They also have more food taboos particularly during pregnancy and lactation. Their low fertility is compounded by nutritional stress. Despite these inequities, Lese women use several strategies to improve their food intake. Since they are responsible for all household cooking, they manipulate food portions. During the hunger season, they snack frequently, and increase their consumption of palliative foods. Women with more food taboos plant larger gardens to supplement their diet with vegetable foods. Although this results in their consumption of more daily protein, they work harder compared to women with smaller gardens. Women cheat in their adherence to specific food taboos by actively discounting them, or by eating prophylactic plants that supposedly prevent the consequences (usually illness) of eating tabooed foods. In addition, women resort to subterfuge to access desirable resources. Lese women do not reduce work effort during the hunger season, but adapt physiologically by reducing resting metabolic rates during periods of weight loss. These results point to the ability of Lese women to minimize the ecological and cultural constraints on their nutrition. More data, however, are required to assess the long-term effectiveness of these strategies.
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Affiliation(s)
- G R Bentley
- Department of Biological Anthropology, University of Cambridge, UK.
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Bentley GR, Harrigan AM, Ellison PT. Dietary composition and ovarian function among Lese horticulturalist women of the Ituri Forest, Democratic Republic of Congo. Eur J Clin Nutr 1998; 52:261-70. [PMID: 9578338 DOI: 10.1038/sj.ejcn.1600547] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE To assess dietary composition in relation to energetic status and ovarian function. DESIGN An eight-month prospective study undertaken in 1989. SETTING Ituri Forest, northeast Democratic Republic of Congo. SUBJECTS Sixty-four female volunteers of reproductive age (16-45), with a subsample of 30 for nutritional focal follows, 39 for analysis of salivary progesterone levels, and 18 for analysis of salivary oestradiol. INTERVENTIONS Regular anthropometric measurements of heights, weights, and mid-triceps skinfolds, 204 h of nutritional focal follows when all foods prepared and consumed were recorded and weighed, analysis of dietary composition using African food tables, collection of saliva samples every-other day for radioimmunoassay of salivary oestradiol and progesterone. RESULTS The primary staple in the Lese diet is manioc, consumed at nearly every meal, but the diet is subject to seasonal fluctuations. Important seasonal crops are groundnuts and rice. Carbohydrates comprise 64% of the diet, protein 14% and fat 22%, but seasonal fluctuations in food items create significant differences in protein content (P = 0.007). Energy intake falls by 25% in the hunger season. Lese energy balance reflects this lack with women losing a mean 7% of total body weight. The mean BMI for Lese women at the beginning of the study was 22.8 but, during the hunger season, the BMI for 20% of women fell to < 18.5, indicative of chronic energy shortage. Mean levels of Lese salivary oestradiol and progesterone are chronically and significantly lower than healthy, Western controls (P = 0.0001 for progesterone; P = 0.03 for follicular values of oestradiol, P = 0.0001 for mid-cycle values, and P = 0.0002 for luteal values). Mean salivary progesterone levels were significantly lower for those Lese women losing weight (P = 0.03), and significantly lower for weight-loss women when comparing levels at the beginning and end of the hunger season (P = 0.03). DISCUSSION The relatively low-fat, high-fibre diet of the Lese appears healthy, but there are occasional seasonal deficiencies in protein-energy and micronutrient content, especially for pregnant and lactating women. Dietary composition may affect Lese levels of reproductive steroids, partly explaining the chronically low salivary oestradiol profile of this population.
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Affiliation(s)
- G R Bentley
- Department of Biological Anthropology, University of Cambridge, England
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Abstract
A relatively untapped area of research concerning lactation and hydration exists for bioanthropologists interested in the ecology of breastfeeding. This review details current limited knowledge on the topic with recommendations about relevant research questions for human biologists. On average, lactating mothers produce >750 ml/day milk for their infants. Breastfeeding thus promotes a powerful thirst stimulus in the lactating mother, resulting in a 12-16% increase in fluid intake among Western women. Thirst during lactation may be mediated by oxytocin release, since this hormone is structurally similar to the antidiuretic hormone, vasopressin. Prolactin also may be involved. A few studies among Western women concluded that moderate dehydration does not affect milk production, but it is not known how lactating women in hot and/or dry climates respond to chronically limited water supplies. Lactating women in such environments may use both physiological and behavioral adaptations to conserve fluid requirements, such as reducing activities during breastfeeding and carrying extra fluid supplies while travelling. Given the limited state of knowledge on lactation and hydration, future field studies should incorporate research to determine the importance of adequate fluids in maintaining milk production and the health of both mothers and infants. Am. J. Hum. Biol. 10:151-161, 1998. © 1998 Wiley-Liss, Inc.
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Affiliation(s)
- G R Bentley
- Department of Biological Anthropology, University of Cambridge, Cambridge, United Kingdom
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Abstract
This paper concerns the analysis of menstrual data; in particular, methodology to identify variables that contribute to the variability of menstrual cycles both within and between women. The basis for the proposed methodology is a parameterization of the mean length of a menstrual cycle conditional upon the past cycles and covariates. This approach accommodates the length-bias and censoring commonly found in menstrual data. Data from a longitudinal study of menstrual patterns and other variables among Lese women of the Ituri Forest, Zaire, illustrate the methodology. A small simulation illustrates the bias caused by incorrectly deleting the censored cycles.
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Affiliation(s)
- S A Murphy
- Department of Statistics, Pennsylvania State University, University Park, USA
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Abstract
Subsequent to a possum (Trichosurus vulpecula) poisoning operation purportedly using 1% phosphorus baits, six dogs with access to poisoned possums died of phosphorus poisoning. Two dogs survived, following treatment with oral copper sulphate and parenteral vitamin K. Clinical signs included depression, jaundice, vomiting and bloody diarrhoea. Post-mortem lesions included large areas of subcutaneous, interstitial and intermuscular haemorrhage, subserosal haemorrhage and liver degeneration. Free phosphorus was detected in the ingesta of three of the dogs which died up to 7 days after the last of the poison was laid. Analysis of two batches of baits used showed P levels of 1.17% and 1.24%.
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Affiliation(s)
- R C Gumbrell
- Lincoln Animal Health Laboratory, MAF Quality Management, PO Box 24, Lincoln, New Zealand
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Affiliation(s)
- G R Bentley
- Department of Anthropology, Northwestern University, Evanston, Illinois 60208
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Bentley GR, Jasienska G, Goldberg T. Is the Fertility of Agriculturalists Higher Than That of Nonagriculturalists? Current Anthropology 1993. [DOI: 10.1086/204223] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Ellison PT, Lipson SF, O'Rourke MT, Bentley GR, Harrigan AM, Panter-Brick C, Vitzthum VJ. Population variation in ovarian function. Lancet 1993; 342:433-4. [PMID: 8101928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Bentley GR, Harrigan AM, Campbell B, Ellison PT. Seasonal effects on salivary testosterone levels among lese males of the Ituri Forest, Zaire. Am J Hum Biol 1993; 5:711-717. [DOI: 10.1002/ajhb.1310050614] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/1992] [Accepted: 07/05/1993] [Indexed: 11/07/2022] Open
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Bentley GR. Health and development in a rural kenyan community. By Jean M. Brainard. New York: Peter Lang. 1991. 216 pp. ISBN 0-8204-0978-2. $38.95 (cloth). Am J Phys Anthropol 1992. [DOI: 10.1002/ajpa.1330890313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
The Lese are subsistence farmers living in the Ituri Forest of north-east Zaïre. They exhibit significant birth seasonality, with lowest frequencies of conception when food production is least, nutritional status is low and ovarian function, as measured by salivary steroid hormone levels, is reduced. Efe pygmy foragers, who live in the same geographical area but are less dependent on cultivated foods and have a more flexible life style, do not exhibit frequent fluctuations in nutritional status nor significant birth seasonality. These findings support a model of birth seasonality relating climatic variables to variation in fertility through a causal chain linking rainfall to food production to energy balance to ovarian function to fertility. The model, which emphasises an ecological approach to the study of human reproduction, should have broad applicability since seasonality of food production and energy balance is widespread geographically and across a wide variety of economies and cultures.
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Bentley GR. : Fertility and Resources . John Landers, Vernon Reynolds. American Anthropologist 1992. [DOI: 10.1525/aa.1992.94.2.02a00670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Rammell CG, Thompson KG, Bentley GR, Gibbons MW. Selenium, vitamin E and polyunsaturated fatty acid concentrations in goat kids with and without nutritional myodegeneration. N Z Vet J 1989; 37:4-6. [PMID: 16031496 DOI: 10.1080/00480169.1989.35536] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Mean selenium and vitamin E (alpha-tocopherol) concentrations in the liver, myocardium and skeletal muscle of nine goat kids with nutritional myodegeneration (NMD) were significantly lower than those in a group of nine kids dying from other causes. Each of the 18 kids was from a different property in the southern half of the North Island. The polyunsaturated fatty acid composition of the liver, myocardium and skeletal muscle was not significantly different between the two groups, but the overall level of peroxidisable polyunsaturated fatty acids appeared high in both groups. A further 21 kids with confirmed NMD and live 'controls', submitted as routine cases to Palmerston North Animal Health Laboratory, were included with the above 18 kids in a comparison of liver selenium and alpha-tocopherol concentrations. Kids with NMD had liver selenium concentrations ranging from 170-1100 (mean = 380) nmol/kg and alpha-tocopherol from 0.7-11.0 (mean =2.2) micromol/kg. In control kids, the liver selenium concentration ranged from 530-4300 (mean = 1220) nmol/kg and a-tocopherol from 1.7-14.0 (mean = 5.6) pmollkg. Although these ranges overlapped, the results suggest that liver selenium concentrations <500 nmol/kg and alpha-tocopherol concentrations <2.5 micromol/kg should be regarded as deficient. Liver selenium concentrations from 500-1100 nmol/kg and alpha-tocopherol concentrations from 2.5-10 micromol/kg should be considered marginal. Goat kids appear to require more selenium than lambs or calves which may explain the higher prevalence of NMD in kids. In some cases, however, the disease is associated with low alpha-tocopherol suggesting that supplementation with selenium alone may not always be sufficient.
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Affiliation(s)
- C G Rammell
- Central Animal Health Laboratory, Ministry of Agriculture and Fisheries, Upper Hutt
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Heath AC, Bishop DM, Bentley GR. The ability of docking fluids containing chlorfenvinphos to prevent the establishment of experimentally-induced flystrike. N Z Vet J 1988; 36:200-1. [PMID: 16031491 DOI: 10.1080/00480169.1988.35531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Rammell CG, Pearson AB, Bentley GR. Vitamin E, selenium and polyunsaturated fatty acids in clinically normal grower (9–16 week old) pigs and their feed: their relationship to the vitamin E/selenium deficiency (“VESD”) syndrome. N Z Vet J 1988; 36:133-7. [PMID: 16031468 DOI: 10.1080/00480169.1988.35508] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Vitamin E, selenium and polyunsaturated fatty acids (PUFAs) were determined in feed used at three piggeries over.a four week period and compared with corresponding concentrations in clinically normal grower pigs at slaughter. Mean values were vitamin E: 59 IU/kg (feed), 6 micromol/kg (liver), 1.7 micromol/l (serum); and selenium: 310 microg/kg (feed), 5200 nmol/kg (liver), 1700 nmol/l (blood). Alpha-tocopherol accounted for 80% of the mean vitamin E activity in the feed and over 95% that in the liver and serum. The mean ratio of PUFA to total fatty acid (FA) in the feed (38%) was similar to that in the serum (36%) and liver (39%), but the ratio of peroxidisable PUFA (PPUFA) to FA increased from 1.7% in the feed to 4.2% in the serum and 10.8% in the liver. The ratio of alpha-tocopherol (mmol) to PPUFA (mol) in the liver varied from 0.16 to 0.48. The relationship of these data to the VESD syndrome is discussed in the light of other published data.
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Affiliation(s)
- C G Rammell
- Central Animal Health Laboratory, Ministry of Agriculture and Fisheries, Upper Hutt, New Zealand
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