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1.
Int J Mol Sci ; 22(18)2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34576301

RESUMO

Organochlorine pesticides, such as DDT, methoxychlor, and their metabolites, have been characterized as endocrine disrupting chemicals (EDCs); suggesting that their modes of action involve interaction with or abrogation of endogenous endocrine function. This study examined whether embryonic thymocyte death and alteration of differentiation induced by the primary metabolite of methoxychlor, HPTE, rely upon estrogen receptor binding and concurrent T cell receptor signaling. Estrogen receptor inhibition of ERα or GPER did not rescue embryonic thymocyte death induced by HPTE or the model estrogen diethylstilbestrol (DES). Moreover, adverse effects induced by HPTE or DES were worsened by concurrent TCR and CD2 differentiation signaling, compared with EDC exposure post-signaling. Together, these data suggest that HPTE- and DES-induced adverse effects on embryonic thymocytes do not rely solely on ER alpha or GPER but may require both. These results also provide evidence of a potential collaborative signaling mechanism between TCR and estrogen receptors to mediate adverse effects on embryonic thymocytes, as well as highlight a window of sensitivity that modulates EDC exposure severity.


Assuntos
Diferenciação Celular , Disruptores Endócrinos/toxicidade , Receptor alfa de Estrogênio/metabolismo , Fenóis/toxicidade , Receptores de Estrogênio/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Timócitos/efeitos dos fármacos , Animais , Antígenos CD2/metabolismo , Morte Celular , Células Cultivadas , Receptor alfa de Estrogênio/antagonistas & inibidores , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores de Estrogênio/antagonistas & inibidores , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Transdução de Sinais , Timócitos/citologia , Timócitos/metabolismo
2.
Gerontologist ; 64(6)2024 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-38502876

RESUMO

BACKGROUND AND OBJECTIVES: Although it is well established that psychological disorders and osteoporosis risk are linked, how the relationship manifests is not. This study examines depressive symptoms and a history of psychological problems as potential risk factors for osteoporosis diagnosis, adjudicating between 4 theoretical models rarely tested together. We analyze these models across multiple domains (i.e., demographic, socioeconomic, and health-related), while accounting for bone mineral density (BMD) scans, which have been shown to improve health equity across sex and racial/ethnic identities. RESEARCH DESIGN AND METHODS: Data from the 2012-2016, nationally representative, population-based, cohort Health and Retirement Study (N = 18,224-18,359) were used to estimate 4 logistic regression models with the outcome of osteoporosis diagnosis. Approximately 50% of the sample identified as female and 50% as male, while about 81% identified as White/European American, 11% as Black/African American, and 8% as another race/ethnicity. The key independent variables were depressive symptoms-measured using two common scales-and a history of psychological problems. RESULTS: A history of psychological problems and one depressive symptoms measure were associated with the odds of osteoporosis diagnosis in the presence of other known risk factors for osteoporosis. DISCUSSION AND IMPLICATIONS: Support for the theoretical models was limited. Evidence suggests possible directionality; a history of psychological distress may be a risk factor for osteoporosis, though we cannot rule out the other direction. Public health professionals and healthcare providers should consider a history of psychological problems as a risk factor for osteoporosis when deciding whether to recommend a BMD scan.


Assuntos
Depressão , Osteoporose , Humanos , Feminino , Masculino , Osteoporose/epidemiologia , Osteoporose/psicologia , Idoso , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Fatores de Risco , Depressão/epidemiologia , Estudos de Coortes , Densidade Óssea , Transtornos Mentais/epidemiologia , Modelos Logísticos , Idoso de 80 Anos ou mais
3.
Heliyon ; 10(1): e23806, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38192805

RESUMO

Existing osteoporosis screening tools have limitations, including using race as a predictor, and development on homogeneous samples. This biases risk assessment of osteoporosis in diverse populations and increases health inequities. We develop a tool that relies on variables easily learned during point-of-care, known by individuals, and with negligible racial bias. Data from the 2012-2016 waves of the population-based cohort Health and Retirement Study (HRS) were used to build a predictive model of osteoporosis diagnosis on a 75 % training sample of adults ages 50-90. The model was validated on a 25 % holdout sample and a cross-sectional sample of American individuals ages 50-80 from the National Health and Nutrition Examination Survey (NHANES). Sensitivity and specificity were compared across sex and race/ethnicity. The model has high sensitivity in the HRS holdout sample (89.9 %), which holds for those identifying as female and across racial/ethnic groups. Specificity is 57.9 %, and area under the curve (AUC) is approximately 0.81. Validation in the NHANES sample using empirically measured osteoporosis produced relatively good values of sensitivity, specificity, and consistency across groups. The model was used to create a publicly-available, open-source tool called the Osteoporosis Health Equality (& Equity) Evaluation (OsteoHEE). The model provided high sensitivity for osteoporosis diagnosis, with consistently high results for those identifying as female, and across racial/ethnic groups. Use of this tool is expected to improve equity in screening and increase access to bone density scans for those at risk of osteoporosis. Validation on alternative samples is encouraged.

4.
JBMR Plus ; 7(5): e10735, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37197319

RESUMO

Demographic and early-life socioeconomic and parental investment factors may influence later-life health and development of chronic and progressive diseases, including osteoporosis, a costly condition common among women. The "long arm of childhood" literature links negative early-life exposures to lower socioeconomic attainment and worse adult health. We build on a small literature linking childhood socioeconomic status (SES) and bone health, providing evidence of whether associations exist between lower childhood SES and maternal investment and higher risk of osteoporosis diagnosis. We further examine whether persons identifying with non-White racial/ethnic groups experience underdiagnosis. Data from the nationally representative, population-based cohort Health and Retirement Study (N = 5,490-11,819) were analyzed for participants ages 50-90 to assess these relationships. Using a machine learning algorithm, we estimated seven survey-weighted logit models. Greater maternal investment was linked to lower odds of osteoporosis diagnosis (odds ratio [OR] = 0.80, 95% confidence interval [CI] = 0.69, 0.92), but childhood SES was not (OR = 1.03, 95% CI = 0.94, 1.13). Identifying as Black/African American (OR = 0.56, 95% CI = 0.40, 0.80) was associated with lower odds, and identifying as female (OR = 7.22, 95% CI = 5.54, 9.40) produced higher odds of diagnosis. There were differences in diagnosis across intersectional racial/ethnic and sex identities, after accounting for having a bone density scan, and a model predicting bone density scan receipt demonstrated unequal screening across groups. Greater maternal investment was linked to lower odds of osteoporosis diagnosis, likely reflecting links to life-course accumulation of human capital and childhood nutrition. There is some evidence of underdiagnosis related to bone density scan access. Yet results demonstrated a limited role for the long arm of childhood in later-life osteoporosis diagnosis. Findings suggest that (1) clinicians should consider life-course context when assessing osteoporosis risk and (2) diversity, equity, and inclusivity training for clinicians could improve health equity. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

5.
Arch Osteoporos ; 16(1): 177, 2021 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-34817704

RESUMO

Chronic stress from social/environmental pressures has been proposed to affect bone health through increased inflammation. We demonstrate that inflammation from prolonged stress does not cause changes to bone health through inflammation but instead impacts access to health care, social inequalities, and overall health, which in turn impact bone health. PURPOSE: The study provides a comprehensive assessment of how determinants of health across demographic, psychological, mobility-related, health, environmental, and economic domains are associated with the diagnosis of osteoporosis and tests three hypotheses: (1) a diverse set of variables across domains will predict osteoporosis, (2) chronic inflammation as a result of stress (represented by high-sensitivity C-reactive protein) will not be associated with osteoporosis, and (3) the model developed will have high accuracy in predicting osteoporosis. METHODS: Logistic regression and Cox proportional hazards models of osteoporosis diagnosis were estimated using data from 14,792 and 13,169 participants (depending on model) in the 2012-2016 waves of the Health and Retirement Study, including the Biomarker Study, the Contextual Data Resource, and validated measures of childhood socioeconomic status. Predictive accuracy was assessed using k-Nearest Neighbors Discriminant Analysis. RESULTS: Demographic, environmental, and health-related factors were associated with osteoporosis diagnosis, and predictive accuracy of the models was good. High-sensitivity C-reactive protein was not associated with osteoporosis diagnosis. CONCLUSION: Social determinants identified indicate access to health care, inequalities in the greater social environment (e.g., access to resources), and overall health (i.e., underlying medical conditions) are key components for developing osteoporosis and indicate underlying health inequities in this sample. There is a need to further address the interplay between primary health care and social determinants of health.


Assuntos
Desigualdades de Saúde , Osteoporose , Idoso , Saúde Ambiental , Humanos , Osteoporose/epidemiologia , Política , Fatores Socioeconômicos
6.
Homo ; 69(4): 147-157, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30055809

RESUMO

The process of the peopling of the Nile Valley likely shaped the population structure and early biological similarity of Egyptians and Nubians. As others have noted, affinity among Nilotic populations was due to an aggregation of events, including environmental, linguistic, and sociopolitical changes over a great deal of time. This study seeks to evaluate the relationships of Nubian and Egyptian groups in the context of the original peopling event. Cranial nonmetric traits from 18 Nubian and Egyptian samples, spanning Lower Egypt to Lower Nubia and approximately 7400 years, were analyzed using Mahalanobis D2 as a measure of biological distance. A principal coordinates analysis and spatial-temporal model were applied to these data. The results reveal temporal and spatial patterning consistent with documented events in Egyptian and Nubian population history. Moreover, the Mesolithic Nubian sample clustered with later Nubian and Egyptian samples, indicating that events prior to the Mesolithic were important in shaping the later genetic patterning of the Nubian population. Later contact through the establishment of the Egyptian fort at Buhen, Kerma's position as a strategic trade center along the Nile, and Egyptian colonization at Tombos maintained genetic similarity among the populations.


Assuntos
Etnicidade/história , Cefalometria , Cromossomos Humanos Y , Egito , Etnicidade/genética , Fósseis , Genética Populacional/história , História Antiga , Humanos , Masculino , Sistemas Políticos/história , Dinâmica Populacional/história
7.
Homo ; 69(5): 237-247, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30269926

RESUMO

This paper focuses on estimating sex by visual assessment of human cranial morphology. Practitioners in the field report variation in sexual dimorphism across populations. This study evaluates again the general hypothesis that populations vary in their pattern of sexual dimorphism. Specifically, the study tests the degree of expression of four cranial morphological traits (glabella, supraorbital margins, nuchal crest, and mastoid process) across three samples from different time periods and which vary in sociocultural transitions: 1) modern Americans of rural and urban areas spanning the last 186 years; 2) Dynastic Egyptians; and 3) Averbuch American Indians, spanning approximately 1255 CE to 1425 CE, from the southeastern United States. These three populations were specifically chosen for sampling as they represent distinct temporal and groups of varied ancestral composition. Crania from these samples were scored 1-5, with 1 being consistent with expected female morphology. The estimated sex was compared to either documented sex (when available) or discriminant functions derived from craniometrics. Freeman-Fisher-Halton tests examined sample differences, within sexes, affecting the visual assessment method. Post hoc tests were applied to pinpoint where the differences lie between the samples. The findings of this study support the hypothesis that the method does not estimate the sex of crania from all populations in the same manner, indicating that populations display differing patterns of sexual dimorphism. However, understanding these patterns and adjusting for how the method is applied will lead to reliable assessments. A relative frequency table and graphs of distributions are provided for practitioners who can use the information to make successful assessments of sex.


Assuntos
População Negra/estatística & dados numéricos , Indígenas Norte-Americanos/estatística & dados numéricos , Determinação do Sexo pelo Esqueleto/métodos , Crânio/anatomia & histologia , Antropologia Física , Egito , Feminino , Humanos , Masculino , Caracteres Sexuais
8.
CBE Life Sci Educ ; 15(4)2016.
Artigo em Inglês | MEDLINE | ID: mdl-27789531

RESUMO

This study examines the relationship between the introduction of a four-course writing-intensive capstone series and improvement in inquiry and analysis skills of biology senior undergraduates. To measure the impact of the multicourse write-to-learn and peer-review pedagogy on student performance, we used a modified Valid Assessment of Learning in Undergraduate Education rubric for Inquiry and Analysis and Written Communication to score senior research theses from 2006 to 2008 (pretreatment) and 2009 to 2013 (intervention). A Fisher-Freeman-Halton test and a two-sample Student's t test were used to evaluate individual rubric dimensions and composite rubric scores, respectively, and a randomized complete block design analysis of variance was carried out on composite scores to examine the impact of the intervention across ethnicity, legacy (e.g., first-generation status), and research laboratory. The results show an increase in student performance in rubric scoring categories most closely associated with science literacy and critical-thinking skills, in addition to gains in students' writing abilities.


Assuntos
Avaliação Educacional/métodos , Revisão por Pares , Pensamento , Redação , Humanos , Fatores de Tempo
9.
Forensic Sci Int ; 210(1-3): 237-42, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21489730

RESUMO

Obesity is a widespread condition affecting modern Americans. The prevalence of obesity has led to questions of how it can affect the skeleton, and if so can it be identified in unknown skeletal material. This study attempts to decipher the effects of activity level and body mass in modern Americans by employing musculoskeletal stress markers (MSM) to estimate osseous responses to workload and body weight. A total sample of 108 skeletons of known activity level and body mass index (BMI) was observed for MSM in the upper extremity (excluding hands). The entheses selected included arm muscles used during the sit-to-stand transition, which is common in most persons, regardless of activity level and BMI. Using the three categories: normal, active, and obese, logistic regression was calculated on MSM to ascertain which markers were the best indicators of these three categories. Numerous muscles of the upper limb were significant predictors of activity level and body mass, although they did not perform much better than chance. MSM may be used as predictors of activity level and/or BMI in forensic contexts; however, they should be used in conjunction with other indications of workload and/or BMI.


Assuntos
Índice de Massa Corporal , Atividade Motora/fisiologia , Músculo Esquelético/fisiologia , Estresse Fisiológico/fisiologia , Antropologia Forense , Humanos , Modelos Logísticos , Masculino , Obesidade/fisiopatologia , Extremidade Superior/fisiologia
10.
Homo ; 60(5): 389-404, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19766993

RESUMO

Many authors have speculated on Nubian biological evolution. Because of the contact Nubians had with other peoples, migration and/or invasion (biological diffusion) were originally thought to be the biological mechanism for skeletal changes in Nubians. Later, a new hypothesis was put forth, the in situ hypothesis. The new hypothesis postulated that Nubians evolved in situ, without much genetic influence from foreign populations. This study examined 12 Egyptian and Nubian groups in an effort to explore the relationship between the two populations and to test the in situ hypothesis. Data from nine cranial nonmetric traits were assessed for an estimate of biological distance, using Mahalanobis D(2) with a tetrachoric matrix. The distance scores were then input into principal coordinates analysis (PCO) to depict the relationships between the two populations. PCO detected 60% of the variation in the first two principal coordinates. A plot of the distance scores revealed only one cluster; the Nubian and Egyptian groups clustered together. The grouping of the Nubians and Egyptians indicates there may have been some sort of gene flow between these groups of Nubians and Egyptians. However, common adaptation to similar environments may also be responsible for this pattern. Although the predominant results in this study appear to support the biological diffusion hypothesis, the in situ hypothesis was not completely negated.


Assuntos
Antropologia Física , Evolução Biológica , Crânio/anatomia & histologia , Egito , Emigração e Imigração , Fluxo Gênico , História do Século XV , História do Século XVI , História Antiga , História Medieval , Humanos , Modelos Biológicos , Sudão
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