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1.
Am J Hum Biol ; 36(5): e24031, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38148505

RESUMO

BACKGROUND: Guatemala suffered from civil war and high levels of inequality and childhood stunting in the second half of the 20th century, but little is known about inequalities in secular trends in adiposity. OBJECTIVES: To investigate differences in childhood body mass index (BMI) and skinfold thickness trajectories from 1979 to 1999 between three groups of children: High socioeconomic position (SEP) Ladino, Low SEP Ladino, and Low SEP Indigenous Maya. METHODS: The sample comprised 19 346 children aged 7-17 years with 54 638 observations. The outcomes were height, BMI, triceps skinfold thickness (TST), and subscapular skinfold thickness (SST) Z-scores according to the Centers for Disease Control and Prevention (CDC) references. Sex-specific multilevel models were used to estimate and compare mean trajectories from 1979 to 1999 between the three groups. RESULTS: Mean Z-scores were always highest for High SEP Ladino children and lowest for Low SEP Maya children. Despite their very short stature, the Low SEP groups had SST trajectories that were above the 50th centile. The BMI trajectories were relatively flat and within one major centile band of the CDC median, with differences between the three groups that were small (0.2-0.3 Z-scores) and did not attenuate over time. Conversely, the TST Z-score trajectories demonstrated larger positive secular trends (e.g., from -1.25 in 1979 to -0.06 in 1999 for Low SEP Maya boys), with differences between the three groups that were large (0.5-1.2 Z-scores) and did attenuate over time (in boys). Secular trends and between-group difference in the SST Z-score trajectories were less pronounced, but again we found stronger evidence in boys that the estimated inequalities attenuated over time. CONCLUSIONS: Secular trends and inequalities in skinfolds differ from those for BMI in Guatemalan children. Differences between groups in skinfolds attenuated over time, at least in boys, but whether this is good news is questionable given the very short stature yet relatively large subscapular skinfolds of the Low SEP groups.


Assuntos
Adiposidade , Índice de Massa Corporal , Dobras Cutâneas , Humanos , Guatemala/epidemiologia , Criança , Masculino , Feminino , Adolescente , Fatores Socioeconômicos
3.
Intelligence ; 80: 101438, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32508371

RESUMO

This study documents differences in childhood IQ trajectories of Guatemala City children, aged 6-15 years and born 1961-1993, according to school attended, height-for-age Z-scores (HAZ) and over time (Flynn effect). IQ data come from the Universidad del Valle de Guatemala Longitudinal Study of Child and Adolescent Development. IQ was measured using standardised tests from the Otis-Lennon Mental Ability Test-series. A multilevel model was developed to describe 60,986 IQ observations (level 1), in 22,724 children (level 2), in five schools representing students of different socioeconomic status (SES) (level 3). Average IQ trajectories differed by school. The difference in average IQ at age 11 years between the students of high and low SES schools was 28.7 points. A one-unit increase in HAZ was associated with a 1.42 (0.72, 2.11) unit higher IQ if HAZ was <0, this association was stronger in public compared to private schools. Conversely, one unit increase in HAZ was only associated with a 0.3 (0.001, 0.5) unit higher IQ if HAZ was ≥0. With each birth year increase, IQ at age 11 years increased by 0.14 (95% CI 0.12, 0.16) units, although this Flynn effect attenuated slightly across adolescence. We found no evidence of secular change in the inequality in IQ trajectories (according to school or HAZ). Shorter children from disadvantaged schools in Guatemala City have lower IQ than their taller and wealthier peers, possibly reflecting the damaging effects of poor early life environments both for linear growth and cognitive development.

4.
Public Health Nutr ; 23(8): 1381-1391, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31801643

RESUMO

OBJECTIVE: To investigate changes in socio-economic inequalities in growth in height, weight, BMI and grip strength in children born during 1955-1993 in Guatemala, a period of marked socio-economic-political change. DESIGN: We modelled longitudinal data on height, weight, BMI and hand grip strength using Super-Imposition by Translation and Rotation (SITAR). Internal Z-scores summarising growth size, timing and intensity (peak growth velocity, e.g. cm/year) were created to investigate inequalities by socio-economic position (SEP; measured by school attended). Interactions of SEP with date of birth were investigated to capture secular changes in inequalities. SETTING: Urban and peri-urban schools in the region of Guatemala City, Guatemala. PARTICIPANTS: Participants were 40 484 children and adolescents aged 3-19 years of Ladino and Maya ancestry (nobservations 157 067). RESULTS: The difference in height (SITAR size) between lowest and highest SEP decreased from -2·0 (95 % CI -2·2, -1·9) sd to -1·4 (95 % CI -1·5, -1·3) sd in males, and from -2·0 (95 % CI -2·1, -1·9) sd to -1·2 (95 % CI -1·3, -1·2) sd in females over the study period. Inequalities also reduced for weight, BMI and grip strength, due to greater secular increases in lowest-SEP groups. The puberty period was earlier and shorter in higher-SEP individuals (earlier SITAR timing and higher SITAR intensity). All SEP groups showed increases in BMI intensity over time. CONCLUSIONS: Inequality narrowed between the 1960s and 1990s. The lowest-SEP groups were still >1 sd shorter than the highest. Risks remain for reduced human capital and poorer population health for urban Guatemalans.


Assuntos
Estatura , Peso Corporal , Fatores Socioeconômicos , Adolescente , Índice de Massa Corporal , Criança , Pré-Escolar , Feminino , Crescimento , Guatemala , Força da Mão , Humanos , Masculino , Puberdade , Estudos Retrospectivos , Adulto Jovem
5.
Am J Hum Biol ; 31(4): e23253, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31090124

RESUMO

OBJECTIVES: The objective of this study was to investigate the association between physical growth in preadult life with five outcomes at ages 64 to 76: weight, body mass index (BMI), estimated body fat percentage, hand grip strength, and mortality. METHODS: Super-imposition by translation and rotation (SITAR) growth curves of 40 484 Guatemalan individuals aged 3 to 19 years were modeled for the parameters of size, timing and intensity (peak growth velocity, eg, cm/year) of height, weight, BMI, and grip strength. Associations between the SITAR parameters and old age outcomes were tested using linear and binary logistic regression for a follow-up sample of high socioeconomic status (SES) Guatemalans, of whom 50 were aged 64 to 76 years at re-measurement and 45 died prior to the year 2017. RESULTS: SITAR models explained 69% to 98% of the variance in each outcome, with height the most precise. Individuals in the follow-up sample who had a higher BMI before the age of 20 years had higher estimated body fat (B = 1.4 CI -0.02-2.8) and BMI (B = 1.2, CI 0.2-2.2) at the ages of 64 to 76 years. Those who grew slower in height but faster in weight and BMI before the age of 20 years had higher BMI and body fat later in life. CONCLUSIONS: These findings highlight the importance of a life course perspective on health and mortality risk. Childhood exposures leading to variation in preadult growth may be key to better understanding health and mortality risks in old age.


Assuntos
Adiposidade , Estatura , Peso Corporal , Força da Mão , Mortalidade , Classe Social , Idoso , Feminino , Guatemala , Humanos , Masculino
7.
Am J Dermatopathol ; 38(11): 832-837, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27322928

RESUMO

A 77-year-old white male presented to the clinic with two isolated cutaneous tumors on his forehead. A cutaneous biopsy showed a focally folliculotropic CD4 cutaneous lymphoma. The tumors were irradiated with a complete response, and he was started on oral bexarotene. He experienced localized cutaneous relapse 3 months into treatment. These new tumors now revealed a surprisingly CD8 cytotoxic phenotype, but with the same clone. A systemic workup was negative. His regimen was switched to romidepsin, and he was treated with local radiation again. Another 3.5 months passed in remission until he developed widespread cutaneous tumors. Positron emission tomography/computed tomography revealed multifocal systemic disease involving his diaphragm, liver, distal duodenum, proximal jejunum, anterior chest wall including pectoral muscles, and lungs without significant adenopathy. He died a few days later. Given his full clinical and pathological course, he was given the diagnosis of an aggressive primary cutaneous T-cell lymphoma, unspecified.


Assuntos
Antineoplásicos/administração & dosagem , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Depsipeptídeos/administração & dosagem , Substituição de Medicamentos , Linfoma Cutâneo de Células T/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Tetra-Hidronaftalenos/administração & dosagem , Idoso , Bexaroteno , Biomarcadores Tumorais/análise , Biópsia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Quimiorradioterapia , Progressão da Doença , Evolução Fatal , Humanos , Imuno-Histoquímica , Imunofenotipagem , Linfoma Cutâneo de Células T/imunologia , Linfoma Cutâneo de Células T/patologia , Masculino , Metástase Neoplásica , Fenótipo , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Resultado do Tratamento
8.
Arch Biochem Biophys ; 579: 8-17, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26032336

RESUMO

The first enzyme in the oxalocrotonate branch of the naphthalene-degradation lower pathway in Pseudomonas putida G7 is NahI, a 2-hydroxymuconate semialdehyde dehydrogenase which converts 2-hydroxymuconate semialdehyde to 2-hydroxymuconate in the presence of NAD(+). NahI is in family 8 (ALDH8) of the NAD(P)(+)-dependent aldehyde dehydrogenase superfamily. In this work, we report the cloning, expression, purification and preliminary structural and kinetic characterization of the recombinant NahI. The nahI gene was subcloned into a T7 expression vector and the enzyme was overexpressed in Escherichia coli ArcticExpress as a hexa-histidine-tagged fusion protein. After purification by affinity and size-exclusion chromatography, dynamic light scattering and small-angle X-ray scattering experiments were conducted to analyze the oligomeric state and the overall shape of the enzyme in solution. The protein is a tetramer in solution and has nearly perfect 222 point group symmetry. Protein stability and secondary structure content were evaluated by a circular dichroism spectroscopy assay under different thermal conditions. Furthermore, kinetic assays were conducted and, for the first time, KM (1.3±0.3µM) and kcat (0.9s(-1)) values were determined at presumed NAD(+) saturation. NahI is highly specific for its biological substrate and has no activity with salicylaldehyde, another intermediate in the naphthalene-degradation pathway.


Assuntos
Aldeído Oxirredutases/química , Aldeído Oxirredutases/ultraestrutura , NAD/química , Naftalenos/química , Pseudomonas putida/enzimologia , Sequência de Aminoácidos , Sítios de Ligação , Simulação por Computador , Ativação Enzimática , Estabilidade Enzimática , Cinética , Modelos Químicos , Modelos Moleculares , Dados de Sequência Molecular , Ligação Proteica , Conformação Proteica , Pseudomonas putida/genética , Proteínas Recombinantes , Especificidade por Substrato
9.
Eat Behav ; 17: 125-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25688801

RESUMO

We explored the hypothesis that perceptions of overweight vary in accord with the prevalence of overweight in specific populations. The present study investigated this relationship in samples from diverse groups in the US and four other countries. The perceptual threshold for overweight is the scalar point at which individuals determine the transition from normal to overweight. Perceptual thresholds for overweight were obtained from 812 adults in Korea, Mexico, Ukraine, Tanzania, and the US (Black, Hispanic, White and college student samples). A linear relationship was observed between the perceptual threshold for overweight and the population prevalence (r=0.52, adjusted R(2)=0.22, F (1/15)=5.24, p<.05), and this relationship was considerably stronger in the non-US samples. This finding links with the results of other studies documenting the influence of the social environment on both weight perception and weight transmission. Together, they suggest that the socio-cultural milieu and weight norms are components of the obesogenic environment and argue for the inclusion of weight norm interventions in weight management programs and public health initiatives.


Assuntos
Comparação Transcultural , Sobrepeso/psicologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Sobrepeso/epidemiologia , Prevalência , República da Coreia/epidemiologia , Tanzânia/epidemiologia , Ucrânia/epidemiologia , Estados Unidos/epidemiologia , Adulto Jovem
10.
J Pediatr ; 166(1): 139-43, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25311710

RESUMO

OBJECTIVE: To provide sex-and-age specific normative values for children and adolescents' accelerometer-determined steps/day, and peak 60-minute cadence adjusted to a pedometer-based scale. STUDY DESIGN: The analysis sample was 2610 children and adolescents (1329 girls) from the 2005-2006 National Health and Nutrition Examination Survey. Accelerometer data were adjusted by eliminating steps counted when activity counts/min <500. Peak 60-minute cadence represented the 60 highest minutes of accumulated steps, averaged over monitored days. Normative data included quintile-defined categories of adjusted steps/day and peak 60-minute cadence for 7 age groups (6-7, 8-9, 10-11, 12-13, 14-15, 16-17, and 18-19 years). LMSChartmakerPro produced 10 age-group-specific smoothed curves (5 for each sex) showing the 5th, 25th, 50th, 75th, and 95th percentiles, respectively, for steps/day and peak 60-minute cadence. RESULTS: Steps/day was inversely associated with age in both boys and girls. The age-associated reduction was apparent in only small decrements for boys; the girl's reduction was steeper. Boys appeared to maintain or increase their peak 60-minute cadence with increased age between 8 and 15 years of age, with a reduction apparent over the last 2 age groups investigated. The peak 60-minute cadence was more variable for girls; a similar sharp reduction (3-6 steps/min) in tandem with the steps/day was apparent between 10- to 11-year-old girls and 12- to 13-year-old girls. CONCLUSIONS: We provided detailed information and normative data pertaining to steps/d and peak 60-minute cadence in US children and adolescents. Like well-known body mass index growth curves, these data may be useful for scientists and clinical practitioners.


Assuntos
Acelerometria/métodos , Actigrafia/métodos , Caminhada/fisiologia , Adolescente , Fatores Etários , Criança , Feminino , Humanos , Masculino , Inquéritos Nutricionais , Valores de Referência , Fatores Sexuais , Estados Unidos , Adulto Jovem
11.
Am J Trop Med Hyg ; 91(3): 611-20, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25002298

RESUMO

During 2010 and 2011, the Loreto region of Peru experienced a dengue outbreak of unprecedented magnitude and severity for the region. This outbreak coincided with the reappearance of dengue virus-2 (DENV-2) in Loreto after almost 8 years. Whole-genome sequence indicated that DENV-2 from the outbreak belonged to lineage II of the southeast Asian/American genotype and was most closely related to viruses circulating in Brazil during 2007 and 2008, whereas DENV-2 previously circulating in Loreto grouped with lineage I (DENV-2 strains circulating in South America since 1990). One amino acid substitution (NS5 A811V) in the 2010 and 2011 isolates resulted from positive selection. However, the 2010 and 2011 DENV-2 did not replicate to higher titers in monocyte-derived dendritic cells and did not infect or disseminate in a higher proportion of Aedes aegypti than DENV-2 isolates previously circulating in Loreto. These results suggest that factors other than enhanced viral replication played a role in the severity of this outbreak.


Assuntos
Aedes/virologia , Vírus da Dengue/classificação , Surtos de Doenças , Genoma Viral/genética , Insetos Vetores/virologia , Dengue Grave/epidemiologia , Adolescente , Adulto , Substituição de Aminoácidos , Animais , Sudeste Asiático , Sequência de Bases , Criança , Vírus da Dengue/genética , Vírus da Dengue/isolamento & purificação , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Peru/epidemiologia , Filogenia , RNA Viral/genética , Análise de Sequência de RNA , Dengue Grave/transmissão , Dengue Grave/virologia , Especificidade da Espécie , Estados Unidos , Adulto Jovem
12.
Postgrad Med ; 124(5): 136-42, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23095433

RESUMO

AIMS: To elucidate the relationship between low circulating serum vitamin D levels and predisease conditions (ie, prediabetes and prehypertension) in healthy Mexican American adults. METHODS: Analyses were conducted using data from the United States National Health and Nutrition Examination Survey (NHANES) from 2001 through 2006. Free-living (ie, community-dwelling, nonimprisoned) adult Mexican American subjects (N = 788; men, n = 443; women, n = 345) who had provided written informed consent and had no history of diabetes, hypertension, dyslipidemia, metabolic syndrome, and/or cardiovascular disease were included in this report. Participants were not ingesting any prescription medications, nor did they exhibit any evidence of malabsorption. Participants were determined to be disease free. RESULTS: The mean serum vitamin D level for Mexican American adults (N = 788) of 50.5 nmol/L was significantly higher (P < 0.0001) than the mean of 35.9 nmol/L for non-Hispanic black adults (n = 621), and significantly lower (P < 0.0001) than the mean of 65.0 nmol/L for non-Hispanic white adults (n = 1711). Although age, sex, and body mass index were all significantly associated with prehypertension and prediabetes, no such association was found for serum vitamin D levels. CONCLUSION: A successive, incremental shift of approximately 15 nmol/L in vitamin D distribution was seen in the transition from the dark-skinned non-Hispanic black population to the brown-skinned Mexican American population, and from the brown-skinned Mexican American population to the non-Hispanic white population. In contrast to the non-Hispanic black and non-Hispanic white populations, wherein previous studies found that serum vitamin D levels below the 75th percentile were associated with prediabetes and prehypertension, no such association was detected among the Mexican American population. The reason for this lack of association among the Mexican American population is unclear.


Assuntos
Americanos Mexicanos , Estado Pré-Diabético/sangue , Pré-Hipertensão/sangue , Vitamina D/sangue , Adulto , Índice de Massa Corporal , Feminino , Humanos , Fígado/metabolismo , Modelos Logísticos , Masculino , Inquéritos Nutricionais
13.
Eat Behav ; 13(3): 188-93, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22664395

RESUMO

Normative, global overweight may play a prominent role in perpetuating the obesity epidemic via its contribution to weight-related norms that describe what is customary in a social environment. These weight-related norms include a perceptual standard determining where body weight shifts from normal to overweight. We introduce the construct of a perceptual threshold for overweight to identify this transition point. The perceptual threshold is measured on 0-100mm scales positioned below adult and child figures. This report presents three studies that evaluate the psychometric properties of this variable. Study 1explored its independence from BMI and body image in factor analyses with diverse samples (Ukrainian, Mexican and US Black, White, and Hispanic). Study 2 was a replication of this factor structure, and Study 3 investigated the reliability of the perceptual threshold using classical test (CT) and generalizability methods (GT). In Studies 1 and 2, two factors were identified (Perceptual Threshold for Overweight and Body Image/BMI) with almost identical factor structures in six analyses. In Study 3 the CT and GT procedures demonstrated adequate reliability. These results indicate that the psychometric properties of the perceptual threshold are sound, and support its use in exploring the social transmission of weight and evaluating obesity prevention and intervention programs.


Assuntos
Imagem Corporal , Peso Corporal , Sobrepeso/psicologia , Adulto , Índice de Massa Corporal , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , Psicometria , Inquéritos e Questionários , Ucrânia , Estados Unidos
14.
J Pediatr ; 160(5): 762-8, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22177991

RESUMO

OBJECTIVES: To investigate secular trends in weight and length growth from birth to 3 years of age in infants born from 1930 to 2008, and to assess whether these trends were associated with concurrent trends in pace of infant skeletal maturation and maternal body mass index. STUDY DESIGN: Longitudinal weight and length data from 620 infants (302 girls) were analyzed with mixed effects modeling to produce growth curves and predicted anthropometry for infants born from 1930 to 1949, 1950 to 1969, 1970 to 1989, and 1990 to 2008. RESULTS: The most pronounced differences in growth occurred in the first year of life. Infants born after 1970 were approximately 450 g heavier and 1.4 cm longer at birth, but demonstrated slower growth to 1 year of age than infants born before 1970. Growth trajectories converged after 1 year of age. There was no evidence that relative skeletal age, maternal body mass index, or maternal age together mediated associations between cohort and growth. CONCLUSIONS: Recent birth cohorts may be characterized not only by greater birth size, but also by subsequent catch-down growth. Trends over time in human growth do not increase monotonically, and growth velocity in the first year may have declined compared with preceding generations.


Assuntos
Peso ao Nascer , Estatura , Desenvolvimento Infantil/fisiologia , Crescimento e Desenvolvimento/fisiologia , Análise de Variância , Composição Corporal , Índice de Massa Corporal , Estudos de Coortes , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Modelos Lineares , Estudos Longitudinais , Masculino , Fatores de Risco , Fatores Sexuais , Fatores de Tempo
15.
Artigo em Inglês | MEDLINE | ID: mdl-11805787

RESUMO

OBJECTIVE: The objective of this study was to determine the degree to which trabecular bone contributes to the radiographic visibility of lamina dura. STUDY DESIGN: Segments of human cadaver mandible were obtained and split longitudinally. Two identical radiographs were made of each segment (1) before the removal of any additional bone and after (2) the removal of a small amount of the lamina dura at the apex of a tooth, (3) block removal of trabecular bone, and (4) smoothing of the endosteal surface of the external cortex. The radiographs were projected in random pairs for each sample. Six dentists judged whether a difference in the amount of lamina dura could be detected between 2 sets of radiographs. RESULTS: Chi-square analysis revealed a significant radiographic difference between radiographs made initially and after removal of the lamina dura and trabecular bone. CONCLUSIONS: Fewer than half of the changes of lamina dura loss alone could be detected radiographically by the observing dentists, whereas nearly all cases of the loss of periapical lamina dura in conjunction with loss of trabecular bone could be detected.


Assuntos
Processo Alveolar/diagnóstico por imagem , Tecido Periapical/diagnóstico por imagem , Idoso , Distribuição de Qui-Quadrado , Humanos , Mandíbula/diagnóstico por imagem , Pessoa de Meia-Idade , Variações Dependentes do Observador , Radiografia
16.
México; El Manual Moderno; c1990. 298 p. tab.
Monografia em Espanhol | BVSNACUY | ID: bnu-3813
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