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1.
Am J Hum Biol ; 35(4): e23839, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36426735

RESUMO

OBJECTIVES: The frequency of cardiovascular diseases has increased throughout the world. People of African descent have been disproportionately affected, particularly if they reside in urban settings. In this work, we evaluate risk factors associated with cardiovascular diseases (CVD) and other chronic diseases in rural and urban Afro-derived communities (quilombo) in Central Brazil. We also determine if there are associations between the frequency of CVD risk factors, sex, and proximity to urban environments. METHODS: Through a cross-sectional study of participants (n = 347) within three Brazilian Afro-derived communities: Kalunga (a semi-isolated rural community; n = 214), Cocalinho (a non-isolated rural village; n = 70), and Pé do Morro (an urban community; n = 63), we collected data regarding chronic disease (i.e., CVD, diabetes, and hypertension) risk through questionnaires, anthropometrics, blood pressure, and blood samples using standard protocols. Differences between variables were tested by the Chi-square test of Pearson and Fisher's Exact Test, independent sample t-tests, analysis of variances, and Kruskal-Wallis tests (p ≤ .05). RESULTS: The prevalence of hypertension, overweight, obesity, and other cardiovascular risk factors were higher in the non-isolated rural and urban communities than in the semi-isolated rural community. We found significant sex differences in the distribution of the CVD risk factors, with all occurring at a higher frequency among females. CONCLUSIONS: Our findings indicate that Brazilian Afro-derived communities are currently going through an epidemiological transition. The urban lifestyle and its environmental factors are likely contributing to an escalation in cardio-metabolic disease risk. However, the magnitude of this transition differentially impacts the sexes, as females suffer a higher frequency of risk factors compared to males.


Assuntos
Doenças Cardiovasculares , Hipertensão , Humanos , Masculino , Feminino , Urbanização , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Fatores de Risco , Brasil/epidemiologia , Estudos Transversais , Hipertensão/epidemiologia , Hipertensão/etiologia , Fatores de Risco de Doenças Cardíacas , Prevalência , População Rural , População Urbana
2.
Am J Hum Biol ; 33(6): e23567, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33458918

RESUMO

OBJECTIVES: To explore evolutionary hypotheses for the high frequencies of a substitution in the methylenetetrahydrofolate reductase (MTHFR) gene, in Mexican and Central American Indigenous populations. MATERIALS AND METHODS: We obtained allele frequencies for the C677T variant in the MTHFR gene and ecological information for 37 indigenous samples from Mexico and Central America. We calculated Hardy-Weinberg equilibrium and computed Fst statistics. We computed correlations between the samples' allele frequencies and ecological and geochemical variables. RESULTS: Many of the samples have extremely high frequencies of the T allele ( q ¯  = 0.62, median = 0.66). In this region, the frequency of the T allele decreases from Southeast to Northwest and is significantly correlated with longitude, latitude, altitude, and insolation. CONCLUSIONS: The native people of Central America and Mexico evolved high frequencies of an allele which has been shown to produce deleterious clinical effects including neural tube effects, cardiovascular events, and cancer. This allele has a clinal distribution in the region, perhaps associated with solar irradiation. As (Contreras-Cubas et al., 2016) noted, the traditional diet of these populations, which is high in folate, has likely mitigated the negative effect of the allele. It is of primary importance that their rights to their homeland and traditional diets be respected. It is a matter of Public Health to investigate whether this allele is a factor in the current wave of cardiovascular diseases affecting the majority population of this region, since it descends from the Native peoples and the Mediterranean population, which also has high frequencies of the allele.


Assuntos
Frequência do Gene , Genética Populacional , Indígenas Centro-Americanos/genética , Metilenotetra-Hidrofolato Redutase (NADPH2) , Alelos , América Central , Genótipo , Humanos , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , México
3.
Int J Mol Sci ; 22(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204176

RESUMO

Age-related bone disorders such as osteoporosis or osteoarthritis are a major public health problem due to the functional disability for millions of people worldwide. Furthermore, fractures are associated with a higher degree of morbidity and mortality in the long term, which generates greater financial and health costs. As the world population becomes older, the incidence of this type of disease increases and this effect seems notably greater in those countries that present a more westernized lifestyle. Thus, increased efforts are directed toward reducing risks that need to focus not only on the prevention of bone diseases, but also on the treatment of persons already afflicted. Evidence is accumulating that dietary lipids play an important role in bone health which results relevant to develop effective interventions for prevent bone diseases or alterations, especially in the elderly segment of the population. This review focuses on evidence about the effects of dietary lipids on bone health and describes possible mechanisms to explain how lipids act on bone metabolism during aging. Little work, however, has been accomplished in humans, so this is a challenge for future research.


Assuntos
Envelhecimento/metabolismo , Osso e Ossos/metabolismo , Gorduras na Dieta/metabolismo , Animais , Autofagia/genética , Biomarcadores , Remodelação Óssea , Dieta , Instabilidade Genômica , Hormônios/metabolismo , Humanos , Osteíte/etiologia , Osteíte/metabolismo , Osteíte/patologia , Estresse Oxidativo
4.
Am J Hum Biol ; 31(5): e23283, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31268232

RESUMO

OBJECTIVE: Life-history strategies promote reproductive fitness and survival. Limited energy availability and competing energetic demands between life-history decisions may result in organismal trade-offs leading to selection for "optimal" traits that facilitate fitness and survival in present environmental conditions. Few life-history analyses have been conducted in food abundant/high resource human populations. Here, we use a life-history theory framework integrated with a biocultural approach to assess whether trade-offs between growth (height) and the onset of reproductive maturation (ages at menarche) were observed in a sample of adult women living in the United States. METHODS: Adult women (18 years and older) from the National Health and Nutrition Examination Survey (NHANES) 2005 to 2006 were analyzed using complex survey regression to evaluate associations between ages at menarche, height, and biological, socio-economic, demographic, and anthropometric variables. Associations between stature, ages at menarche, and socio-economic status (household income and education level) suggest life-history trade-offs in this populations may be mitigated by access to resources and marginalization. CONCLUSIONS: These study results have applied public health implications. We demonstrate that females who experience early menarche in the US population achieve short stature. Our study also demonstrates the need for implementing life-history analyses in Western affluent populations, where marginalization may result in life-history trade-offs.


Assuntos
Estatura , Características de História de Vida , Menarca , Reprodução , Fatores Socioeconômicos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Feminino , Humanos , Pessoa de Meia-Idade , Inquéritos Nutricionais , Estados Unidos , Adulto Jovem
5.
South Med J ; 112(5): 289-294, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31050799

RESUMO

OBJECTIVES: This study investigates whether genetic modifiers previously shown to influence adult fetal hemoglobin (HbF) levels and glucose-6-phosphate dehydrogenase deficiency were associated with variable symptomology in a small sample of collegiate football players with sickle cell trait. METHODS: Survey data on self-assessed symptoms and genotype data from five single nucleotide polymorphisms (SNPs) related to HbF production and two SNPs that cause glucose-6-phosphate dehydrogenase deficiency were collected from current and former college football players. RESULTS: In this sample, SNPs found within the ß-globin gene cluster were found to be associated with a previous diagnosis of exertional sickling and experience of extreme heat during and after training. rs10189857 in the BCL11A gene was associated with body mass index and weight and with experiencing extreme thirst during and after training. No significant correlations were found between the other SNPs and symptoms within this sample. CONCLUSIONS: These findings show that genetic variation known to affect sickle cell disease symptomology may partly explain why some football players with sickle cell trait experience adverse clinical outcomes during periods of extreme physical exertion and others do not.


Assuntos
Hemoglobina Fetal/metabolismo , Futebol Americano , Polimorfismo de Nucleotídeo Único , Traço Falciforme/sangue , Adulto , DNA/genética , Feminino , Genótipo , Humanos , Masculino , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Traço Falciforme/genética
6.
Am J Hum Biol ; 27(5): 605-12, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25882505

RESUMO

OBJECTIVES: We examine if there are genetic and environmental differences between mothers of singleton and multiple pregnancies in a sample of African-American mothers. METHODS: We focus on genomic areas suggested to increase or decrease the odds of multiple pregnancies. We computed the odds ratio (OR) and the 95% confidence interval (CI) for each SNP unadjusted or adjusted with smoking. SNPs' allelic differences between mothers of multiple pregnancies and singletons were also tested using Fisher's exact test. We considered additive terms for the SNPs' genotypes, smoking, and a multiplicative interaction term of two selected SNPs' genotypes. RESULTS: We found significant interactions between smoking and SNPs of the CYP19A, MDM4, MTHFR and TP53 genes which correlated with higher odds of twinning. We also found a significant interaction between SNPs at the TP53 (rs8079544) and MTHFR gene (rs4846049), where the interaction between the homozygotes (TT for rs8079544, GG for rs4846049) correlated with lowered odds of multiple pregnancy. CONCLUSIONS: We provide a mechanistic explanation and preliminary evidence for previous reports that mothers of twins are more likely to have smoked, despite seemingly conflicting evidence for the fertility-reducing effects of nicotine. Nicotine, as an aromatase inhibitor, inhibits estrogen synthesis and may allow for greater production of gonadotropins. While smoking may have deleterious effects on fertility across many genotypes, in women of specific genotypes it may raise their odds of producing twins. TP53 involvement suggests the necessity of future work examining relationships between women who bear multiples and cancer risk.


Assuntos
Recém-Nascido de Peso Extremamente Baixo ao Nascer , Polimorfismo de Nucleotídeo Único , Gravidez Múltipla , Fumar/epidemiologia , Adulto , Negro ou Afro-Americano , Feminino , Humanos , Recém-Nascido , Paridade , Gravidez , Gêmeos , Estados Unidos , Adulto Jovem
7.
Hum Biol ; 86(4): 251-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25959692

RESUMO

Interest in mitochondrial influences on extended longevity has been mounting, as evidenced by a growing literature. Such work has demonstrated that some haplogroups are associated with increased longevity and that such associations are population specific. Most previous work, however, suffers from the methodological shortcoming that long-lived individuals are compared with "controls" who are born decades after the aged individuals. The only true controls of the elderly are people who were born in the same time period but who did not have extended longevity. Here we present results of a study in which we are able to test whether longevity is independent of haplogroup type, controlling for time period, by using mtDNA genealogies. Since mtDNA does not recombine, we know the mtDNA haplogroup of the maternal ancestors of our living participants. Thus, we can compare the haplogroup of people with and without extended longevity who were born during the same time period. Our sample is an admixed New World population that has haplogroups of Amerindian, European, and African origin. We show that women who belong to Amerindian, European, and African haplogroups do not differ in their mean longevity. Therefore, to the extent that ethnicity was tied in this population to mtDNA make-up, such ethnicity did not impact longevity. In support of previous suggestions that the link between mtDNA haplogroups and longevity is specific to the population being studied, we found an association between haplogroup C and decreased longevity. Interestingly, the lifetime reproductive success and the number of grandchildren produced via a daughter of women with haplogroup C are not reduced. Our diachronic approach to the mtDNA and longevity link allowed us to determine that the same haplogroup is associated with decreased longevity during different time periods and allowed us to compare the haplogroup of short- and long-lived individuals born during the same time period. By controlling for time period, we minimized the effect of different cultural and ecological environments on differential longevity. With our diachronic approach, we investigated the mtDNA and longevity link with a biocultural perspective.


Assuntos
Indígena Americano ou Nativo do Alasca , População Negra , DNA Mitocondrial/genética , Haplótipos , Longevidade/genética , População Branca , Envelhecimento/genética , Indígena Americano ou Nativo do Alasca/genética , Indígena Americano ou Nativo do Alasca/estatística & dados numéricos , População Negra/genética , População Negra/estatística & dados numéricos , Costa Rica/epidemiologia , Evolução Cultural , Feminino , Humanos , Masculino , Filogenia , População Branca/genética , População Branca/estatística & dados numéricos
8.
Am J Phys Anthropol ; 148(3): 327-33, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22460349

RESUMO

Estimates of mutation rates for the noncoding hypervariable Region I (HVR-I) of mitochondrial DNA vary widely, depending on whether they are inferred from phylogenies (assuming that molecular evolution is clock-like) or directly from pedigrees. All pedigree-based studies so far were conducted on populations of European origin. In this article, we analyzed 19 deep-rooting pedigrees in a population of mixed origin in Costa Rica. We calculated two estimates of the HVR-I mutation rate, one considering all apparent mutations, and one disregarding changes at sites known to be mutational hot spots and eliminating genealogy branches which might be suspected to include errors, or unrecognized adoptions along the female lines. At the end of this procedure, we still observed a mutation rate equal to 1.24 × 10(-6) , per site per year, i.e., at least threefold as high as estimates derived from phylogenies. Our results confirm that mutation rates observed in pedigrees are much higher than estimated assuming a neutral model of long-term HVRI evolution. We argue that until the cause of these discrepancies will be fully understood, both lower estimates (i.e., those derived from phylogenetic comparisons) and higher, direct estimates such as those obtained in this study, should be considered when modeling evolutionary and demographic processes.


Assuntos
DNA Mitocondrial/genética , Taxa de Mutação , Linhagem , Adulto , Costa Rica , Feminino , Variação Genética/genética , Genética Populacional , Humanos , Mães
9.
Hum Biol ; 83(1): 71-86, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21453005

RESUMO

The effects of migration on human health have been a topic of interest for demographers and human biologists. Even if migrants to a new region achieve a higher standard of living in their new place of residence, their improved living conditions may not be associated with better health. Part of the difficulty of understanding the health consequences of migration is the complications in trying to control for variables that may affect health, such as gender, age, and urban or rural environment of migrants and nonmigrants. In this paper we report results of a meta-analysis of the body mass index (BMI) and blood pressure (BP) of people of South Asian descent, by comparing nonmigrants who inhabit the subcontinent, with migrants who moved to various places around the globe. Our results indicate that BMI almost always increases to a significant level upon migration and that an increase in BMI is most pronounced in female migrants. Our results also show that BP does not always increase in migrant communities and that it is actually lower in some migrant samples than it is in comparable nonmigrant groups. Therefore, our results show that BP and the BMI do not behave in the same manner following a migration event. We propose that the BMI changes experienced by migrants are likely to reflect different activity levels and diet in the new homeland. However, the BP changes experienced by migrants are likely to reflect stress broadly defined. Such stress may be increased or decreased, depending on the specific migration experience. We propose that the BMI and BP measure two different dimensions of the migration experience.


Assuntos
Emigração e Imigração/estatística & dados numéricos , Genética Populacional/estatística & dados numéricos , Hipertensão/epidemiologia , Obesidade/epidemiologia , População Urbana/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Austrália/epidemiologia , Pressão Sanguínea , Índice de Massa Corporal , Feminino , Saúde Global , Humanos , Índia/etnologia , Masculino , Países Baixos/epidemiologia , Noruega/epidemiologia , Prevalência , Risco , Singapura/epidemiologia , Estresse Fisiológico , Estresse Psicológico , Reino Unido/epidemiologia , Adulto Jovem
10.
Am J Hum Biol ; 23(2): 225-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21319252

RESUMO

OBJECTIVE: To determine if individuals who carry mitochondrial markers which have been previously shown to affect longevity also have differential lifetime reproductive success (LRS). METHODS: We extracted the mtDNA from living subjects residing in Atenas, Costa Rica. Since mtDNA does not recombine, and its probability of mutation is low, we assume that all maternal ancestors of the living subjects have the same mtDNA. We reconstructed the maternal genealogy of the living subjects, so that we have information on the LRS and longevity of the maternal ancestors of the living subjects. We compared the LRS of women who carried the 5178A marker in haplogroup D (associated with decreased longevity) and who carried the 150T polymorphism (associated with increased longevity) with the LRS of controls born in the same half century time period from 1750 to 1939. RESULTS: We found that the LRS of neither group of women with a longevity-associated polymorphism (LAP) differed from the LRS of controls, even if these women differed significantly from the controls in their longevity. CONCLUSIONS: Although LAPS significantly affect longevity, such differential longevity does not result in differential lifetime reproductive success. From an evolutionary perspective, these longevity-associated polymorphisms do not affect the carriers' Darwinian fitness.


Assuntos
DNA Mitocondrial/genética , Aptidão Genética , Longevidade/genética , Linhagem , Polimorfismo Genético , Costa Rica , Feminino , Haplótipos , História do Século XVIII , História do Século XIX , História do Século XX , Humanos
11.
Hum Hered ; 67(3): 147-53, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19077432

RESUMO

Previous work compared frequency of longevity-associated polymorphisms (LAPS) in long-lived individuals and in controls from the general population (primarily in Europe and Japan), suggesting the polymorphisms are responsible for unusual longevity. However, individuals from the general population are not the control group for long-lived subjects because both were born in different periods. We report results of a project which collected mtDNA from living subjects in Costa Rica, and traced back their maternal genealogy. Since mtDNA does not recombine and its probability of mutation is low, we can assume that the maternal ancestors had the same mtDNA of their descendants. We compared the longevity of individuals with LAPS with the longevity of controls born in the same time period. We did not confirm previous associations for several markers, but found that the 5178A mutation in haplogroup D is associated with decreased longevity, whereas the 150T mutation is associated with increased longevity. These associations however, are not significant for all time periods under study. While our data confirm that mtDNA make up affects longevity, they also indicate that the time period in which a person was born had a much greater impact on longevity than presence or absence of a marker.


Assuntos
DNA Mitocondrial/genética , Longevidade/genética , Polimorfismo Genético , Análise de Variância , Costa Rica , Marcadores Genéticos , Haplótipos , Humanos , Mutação , Estatísticas não Paramétricas
12.
Am J Phys Anthropol ; 136(2): 223-9, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18322917

RESUMO

The evolution of postmenopausal longevity in human females has been the subject of debate. Specifically, there is disagreement about whether the evolution of the trait should be understood as an adaptive or a neutral process, and if the former, what the selective mechanism is. There are two main adaptive proposals to explain the evolution of postreproductive longevity: the grandmother and the mother hypotheses. The grandmother hypothesis proposes that postreproductive longevity evolved because it is selectively advantageous for females to stop reproducing and to help raise their grandchildren. The mother hypothesis states that postmenopausal longevity evolved because it is advantageous for women to cease reproduction and concentrate their resources and energy in raising the children already produced. In this article, we test the mother and the grandmother hypotheses with a historical data set from which we bootstrapped random samples of women from different families who lived from the 1500s to the 1900s in the central valley of Costa Rica. We also compute the heritability of longevity, which allows us to determine if genes involved in longevity are nearly fixed in this population. Here we show that although longevity positively affects a woman's fertility, it negatively affects her daughter's fertility; for this reason, the heritability of longevity is unexpectedly high. Our data provide strong grounds for questioning the universality of the grandmother hypothesis and for supporting the mother hypothesis as a likely explanation for the evolution of human postreproductive longevity.


Assuntos
Características da Família , Fertilidade/fisiologia , Longevidade/fisiologia , Antropologia Física/métodos , Feminino , Humanos , Expectativa de Vida , Menopausa , Reprodução/fisiologia
13.
Arch Latinoam Nutr ; 57(4): 387-96, 2007 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-18524324

RESUMO

Inulin is a non-digestible carbohydrate that is contained in many vegetables, fruits and cereals. It is industrially produced from the chicory's root (Cichorium intybus) and it is widely used as ingredient in functional foods. Inulin and its derivate compounds (oligofructose, fructooligosaccharides) are usually called fructans, as they are basically based on linear fructose chains. This review presents a description of inulin and its most common derivate compounds: chemical structure, natural sources, physic-chemical properties, technological functionality, industrial manufacturing, analytical method for determination and health benefits: prebiotic, dietary fiber, low caloric value, hypoglycemic action, enhancement of calcium and magnesium bioavailability. Potential benefits: lipid parameters regulation, reduction of colon cancer risk and others, improvement of immune response, intestinal disorders protection. From technological point of view, these compounds exhibit a variety of properties: thickener, emulsifier, gel forming, sugar and fat substitute, humectant, freezing point depression. Inulin and derivates are been used in pharmaceutical, chemical and processing industry as technological additives and excipients. They are also been used for animal feeding. They are been considered as "bioactive" compounds to be proposed as future packaging material. Fructans are proposed to be classified as "functional fiber", according to recent concepts based on physiological effects on individuals. This review of inulin and its derivates was useful to show the broad boundaries of these compounds in the food industry and why they may be considered as key ingredients in the expanding functional food market.


Assuntos
Tecnologia de Alimentos , Alimentos Orgânicos , Inulina , Oligossacarídeos , Cichorium intybus/química , Humanos , Inulina/administração & dosagem , Inulina/química , Inulina/isolamento & purificação , Valor Nutritivo , Oligossacarídeos/administração & dosagem , Oligossacarídeos/química , Oligossacarídeos/isolamento & purificação
14.
Am J Hum Biol ; 3(2): 105-110, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-28520241

RESUMO

The accuracy of recalled age at first menses has been questioned, particularly if subjects are relatively old. This paper illustrates the use of a statistical technique that quantifies the reliability of recalled age at menarche based on re-interview of a small (15-20) subsample of subjects. Menarcheal age collected with the retrospective method in a sample of 108 females, 50 years of age and older, from Limón, Costa Rica, is reliable.

15.
Am J Hum Biol ; 3(6): 625-628, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-28524289

RESUMO

This paper examines the association between menarcheal age and risk of spontaneous abortion with a data set collected in Limon, Costa Rica. The Limonense sample differs from those previously reported in terms of age, socioeconomic and ethnic background. Thus, the sample is excellent to test whether menarcheal age and risk of miscarriage are associated in a nonindustrialized group as they appear to be in industrialized samples. Females who experienced one or more miscarriages have a significantly earlier age at first menses than those who did not. The results also indicate that a possible reason for this association is that early maturers tend to experience first pregnancy at an earlier age than do late maturers.

16.
Am J Phys Anthropol ; 132(3): 470-82, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16685728

RESUMO

Applied to skin color, the sexual selection hypothesis proposes that male preference for light-skinned females explains the presence of light skin in areas of low solar radiation. According to this proposal, in areas of high solar radiation, natural selection for dark skin overrides the universal preference of males for light females. But in areas in which natural selection ceases to act, sexual selection becomes more important, and causes human populations to become light-skinned, and females to be lighter than males. The sexual selection hypothesis proposes that human sexual dimorphism of skin color should be positively correlated with distance from the equator. We tested the prediction that sexual dimorphism should increase with increasing latitude, using adult-only data sets derived from measurements with standard reflectance spectrophotometric devices. Our analysis failed to support the prediction of a positive correlation between increasing distance from the equator and increased sexual dimorphism. We found no evidence in support of the sexual selection hypothesis.


Assuntos
Seleção Genética , Comportamento Sexual , Pigmentação da Pele , Feminino , Geografia , Humanos , Masculino
17.
Am J Phys Anthropol ; 134(2): 175-89, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17568447

RESUMO

After the emancipation of African slaves in the Caribbean, the labor void left by out-migrating former slaves was filled by in-migrating indentured servants from prepartition India and China. In some areas of the Caribbean such as Trinidad, Suriname, and Guyana, the East-Indian migrants formed large communities. In this article, we report a study based on mtDNA and Y-chromosomal markers of a small East-Indian community from Limón, Costa Rica. The purpose of the project is to determine the place of origin in the Indian subcontinent of the ancestors of our group and the contributions to its gene pool through gene flow by members of other ethnic groups. Both Y-chromosome and mtDNA suggest that the Indo-Costa Ricans descend from migrants primarily from Central India. While both paternal and maternal markers indicate that this group is overwhelmingly of Indian origin, they also indicate that males and females of African, European, and Amerindian origin contributed to it differently. We discuss our results in the historical context of the virtual extinction of Amerindian Caribbean groups, the forced migration of African slaves to the Caribbean, and the gene flow between Amerindians, Europeans, East-Indians, and Africans that eventually produced the Caribbean's currently diverse gene pool.


Assuntos
Povo Asiático/genética , Emigração e Imigração/história , Fluxo Gênico , Variação Genética , África/etnologia , Ásia Ocidental/etnologia , Povo Asiático/história , Cromossomos Humanos Y , Costa Rica , DNA Mitocondrial , Feminino , Haplótipos , História do Século XVIII , História do Século XIX , Humanos , Masculino , Filogenia , Dinâmica Populacional , Análise de Sequência de DNA
18.
Am J Hum Biol ; 15(1): 16-22, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12552574

RESUMO

This study researched the impact of anthropometrics and size-of-family of orientation on women's fertility by using path analysis. The data were collected as part of the anthropological study conducted in Ireland by Harvard University personnel before the Second World War. The women included in this analysis were all over age 49 and were either married or widowed at the time of the survey. Our results indicate that the heritability of fertility is moderate in this sample and that there is a tendency for heavy women to have a higher fertility. However, when anthropometrics and size-of-family of orientation were entered as independent variables in a path diagram, an insignificant portion of the variation of fertility was explained. In this Irish population, the main cause of differential fertility was cultural rather than biological. A large portion of women never married and no unmarried woman reported producing a child.


Assuntos
Fertilidade/genética , Antropometria , Características da Família , Feminino , Hereditariedade , Humanos , Pessoa de Meia-Idade
19.
Arch. latinoam. nutr ; 57(4): 387-396, dic. 2007. tab, graf
Artigo em Espanhol | LILACS | ID: lil-486735

RESUMO

La inulina es un carbohidrato no digerible que está presente en muchos vegetales, frutas y cereales. En la actualidad, a nivel industrial se extrae de la raíz de la achicoria (Cichorium intybus) y se utiliza ampliamente como ingrediente en alimentos funcionales. La inulina y sus derivados (oligofructosa, fructooligosacáridos) son generalmente llamados fructanos, que están constituidos básicamente por cadenas lineales de fructosa. En esta revisión se presenta una descripción de la inulina y sus compuestos derivados más comunes, su estructura química, fuentes de obtención, características físicas y químicas, funcionalidad tecnológica, producción industrial, método analítico de determinación, sus beneficios a la salud como prebiótico, aporte de fibra dietética, bajo valor calórico, hipoglicemiante, mejorador de la biodisponibilidad de calcio y magnesio. Se presentan evidencias promisorias de su actuación en la regulación de parámetros inmune y protección contra desórdenes intestinales. En una amplia variedad de productos alimenticios se usa la inulina y sus derivados como: espesante, emulsificante, gelificante, sustituto de azúcares y de grasas, humectante, depresor del punto de congelación. También se emplean en la industria química-farmacéutica y de procesamiento como excipiente, aditivo, agente tecnológico o coadyudante; en la industria de la alimentación animal, y se está considerando su uso como constituyente de los empaques por su carácter de material bioactivo. Se ha propuesto catalogar a los fructanos como "fibra funcional", en base a una nueva clasificación de la fibra dietética que considera el efecto fisiológico en el individuo. A través de esta revisión se evidenció el vaso alcance de estos compuestos en la industria alimentaria y las razones por las que resultan ser ingredientes claves en el pujante mercado de los alimentos funcionales.


Assuntos
Fibras na Dieta , Tecnologia de Alimentos , Frutanos , Alimento Funcional , Inulina , Fenômenos Biológicos , Ciências da Nutrição , Venezuela
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