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1.
Evol Hum Behav ; 43(6): 527-535, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36217369

RESUMO

The COVID-19 pandemic caused drastic social changes for many people, including separation from friends and coworkers, enforced close contact with family, and reductions in mobility. Here we assess the extent to which people's evolutionarily-relevant basic motivations and goals-fundamental social motives such as Affiliation and Kin Care-might have been affected. To address this question, we gathered data on fundamental social motives in 42 countries (N = 15,915) across two waves, including 19 countries (N = 10,907) for which data were gathered both before and during the pandemic (pre-pandemic wave: 32 countries, N = 8998; 3302 male, 5585 female; M age  = 24.43, SD = 7.91; mid-pandemic wave: 29 countries, N = 6917; 2249 male, 4218 female; M age  = 28.59, SD = 11.31). Samples include data collected online (e.g., Prolific, MTurk), at universities, and via community sampling. We found that Disease Avoidance motivation was substantially higher during the pandemic, and that most of the other fundamental social motives showed small, yet significant, differences across waves. Most sensibly, concern with caring for one's children was higher during the pandemic, and concerns with Mate Seeking and Status were lower. Earlier findings showing the prioritization of family motives over mating motives (and even over Disease Avoidance motives) were replicated during the pandemic. Finally, well-being remained positively associated with family-related motives and negatively associated with mating motives during the pandemic, as in the pre-pandemic samples. Our results provide further evidence for the robust primacy of family-related motivations even during this unique disruption of social life.

2.
Mol Cell Biochem ; 461(1-2): 91-102, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31375973

RESUMO

Peroxiredoxins (Prdxs) are antioxidant enzymes that catalyse the breakdown of peroxides and regulate redox activity in the cell. Peroxiredoxin 5 (Prdx5) is a unique member of Prdxs, which displays a wider subcellular distribution and substrate specificity and exhibits a different catalytic mechanism when compared to other members of the family. Here, the role of a key metabolic integrator coenzyme A (CoA) in modulating the activity of Prdx5 was investigated. We report for the first time a novel mode of Prdx5 regulation mediated via covalent and reversible attachment of CoA (CoAlation) in cellular response to oxidative and metabolic stress. The site of CoAlation in endogenous Prdx5 was mapped by mass spectrometry to peroxidatic cysteine 48. By employing an in vitro CoAlation assay, we showed that Prdx5 peroxidase activity is inhibited by covalent interaction with CoA in a dithiothreitol-sensitive manner. Collectively, these results reveal that human Prdx5 is a substrate for CoAlation in vitro and in vivo, and provide new insight into metabolic control of redox status in mammalian cells.


Assuntos
Coenzima A/metabolismo , Peroxirredoxinas/metabolismo , Processamento de Proteína Pós-Traducional , Animais , Análise Mutacional de DNA , Células HEK293 , Humanos , Masculino , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Ratos Sprague-Dawley , Ratos Wistar , Estresse Fisiológico/efeitos dos fármacos
3.
Biochem J ; 475(11): 1909-1937, 2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29626155

RESUMO

In all living organisms, coenzyme A (CoA) is an essential cofactor with a unique design allowing it to function as an acyl group carrier and a carbonyl-activating group in diverse biochemical reactions. It is synthesized in a highly conserved process in prokaryotes and eukaryotes that requires pantothenic acid (vitamin B5), cysteine and ATP. CoA and its thioester derivatives are involved in major metabolic pathways, allosteric interactions and the regulation of gene expression. A novel unconventional function of CoA in redox regulation has been recently discovered in mammalian cells and termed protein CoAlation. Here, we report for the first time that protein CoAlation occurs at a background level in exponentially growing bacteria and is strongly induced in response to oxidizing agents and metabolic stress. Over 12% of Staphylococcus aureus gene products were shown to be CoAlated in response to diamide-induced stress. In vitro CoAlation of S. aureus glyceraldehyde-3-phosphate dehydrogenase was found to inhibit its enzymatic activity and to protect the catalytic cysteine 151 from overoxidation by hydrogen peroxide. These findings suggest that in exponentially growing bacteria, CoA functions to generate metabolically active thioesters, while it also has the potential to act as a low-molecular-weight antioxidant in response to oxidative and metabolic stress.


Assuntos
Antioxidantes/metabolismo , Proteínas de Bactérias/metabolismo , Coenzima A/metabolismo , Staphylococcus aureus/metabolismo , Proteínas de Bactérias/genética , Coenzima A/genética , Diamida/farmacologia , Gliceraldeído-3-Fosfato Desidrogenases/genética , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Oxirredução , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética
4.
J Res Adolesc ; 29(2): 449-465, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-29570890

RESUMO

This study examines how student perceptions of teacher practices contribute to female high school students' math beliefs and achievement. Guided by the expectancy-value framework, we hypothesized that students' motivation beliefs and achievement outcomes in mathematics are fostered by teachers' emphasis on the relevance of mathematics and constrained by gender-based differential treatment. To examine these questions, structural equation modeling was applied to a longitudinal panel of 518 female students from the Maryland Adolescent Development in Context Study. While controlling for prior achievement and race, gendered differential treatment was negatively associated with math beliefs and achievement, whereas relevant math instruction was positively associated with these outcomes. These findings suggest inroads that may foster positive math motivational beliefs and achievement among young women.


Assuntos
Sucesso Acadêmico , Atitude , Cultura , Matemática , Mulheres/psicologia , Adolescente , Feminino , Humanos , Professores Escolares , Autorrelato
5.
Biochem J ; 474(14): 2489-2508, 2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28341808

RESUMO

Coenzyme A (CoA) is an obligatory cofactor in all branches of life. CoA and its derivatives are involved in major metabolic pathways, allosteric interactions and the regulation of gene expression. Abnormal biosynthesis and homeostasis of CoA and its derivatives have been associated with various human pathologies, including cancer, diabetes and neurodegeneration. Using an anti-CoA monoclonal antibody and mass spectrometry, we identified a wide range of cellular proteins which are modified by covalent attachment of CoA to cysteine thiols (CoAlation). We show that protein CoAlation is a reversible post-translational modification that is induced in mammalian cells and tissues by oxidising agents and metabolic stress. Many key cellular enzymes were found to be CoAlated in vitro and in vivo in ways that modified their activities. Our study reveals that protein CoAlation is a widespread post-translational modification which may play an important role in redox regulation under physiological and pathophysiological conditions.


Assuntos
Coenzima A/metabolismo , Proteínas/metabolismo , Animais , Cisteína/metabolismo , Células HEK293 , Células Hep G2 , Humanos , Rim/metabolismo , Fígado/metabolismo , Masculino , Miocárdio/metabolismo , Especificidade de Órgãos , Oxirredução , Estresse Oxidativo , Processamento de Proteína Pós-Traducional , Coelhos , Ratos Sprague-Dawley , Compostos de Sulfidrila/metabolismo
6.
Monogr Soc Res Child Dev ; 82(4): 7-28, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29130252

RESUMO

In this monograph, we investigate the developmental trajectories of a predominantly middle-class, community-based sample of European American and African American adolescents growing up in urban, suburban, and rural areas in Maryland, United States. Within risk-protection and positive youth development frameworks, we selected developmental measures based on the normative tasks of adolescence and the most widely studied indicators in the three major contexts of development: families, peer groups, and schools. Using hierarchical linear growth models, we estimated adolescents' growth trajectories from ages 12 to 20 with variation accounted for by socioeconomic status (SES), gender, race/ethnicity, and the gender by race/ethnicity interaction. In general, the results indicate that: (a) periods of greatest risk and positive development depended on the time frame and outcome being examined and (b) on average, these adolescents demonstrated much stronger evidence of positive than problematic development, even at their most vulnerable times. Absolute levels of their engagement in healthy behaviors, supportive relationships with parents and friends, and positive self-perceptions and psychological well-being were much higher than their reported angry and depressive feelings, engagement in risky behaviors, and negative relationships with parents and peers. We did not find evidence to support the idea that adolescence is a time of heightened risk. Rather, on average, these adolescents experienced relatively stable and developmentally healthy trajectories for a wide range of characteristics, behaviors, and relationships, with slight increases or decreases at different points in development that varied according to domain. Developmental trajectories differed minimally by SES but in some expected ways by gender and race/ethnicity, although these latter differences were not very marked. Overall, most of the young people navigated through their adolescence and arrived at young adulthood with good mental and physical health, positive relationships with their parents and peers, and high aspirations and expectations for what their future lives might hold.


Assuntos
Desenvolvimento do Adolescente , Negro ou Afro-Americano/psicologia , População Branca/psicologia , Sucesso Acadêmico , Adolescente , Características da Família , Humanos , Satisfação Pessoal , Comportamento Problema , Meio Social , Identificação Social
7.
J Soc Pers Relat ; 34(8): 1168-1185, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36714796

RESUMO

Within the field of relationship science there is increasing interest in the connections between close relationships and physical health. In the present study, we examined whether adolescents' (~12 years old) and young adults' (~20 years old) perceptions of their parents as a secure base prospectively predict C-reactive protein (CRP), a commonly used marker of inflammatory activity, at age 32 in a well-characterized sample of African Americans. We utilized existing data collected as part of the Maryland Adolescent Development in Context Study (MADICS) to construct measures of perceptions of parental secure base support (SBS), general parental support, and peer support in early adolescence and early adulthood. In the present study, SBS was operationalized as the perceived ability to depend on parents in times of need. Fifty-nine African American MADICS participants who reported on perceived support in early adolescence and early adulthood participated in a follow-up home visit at age 32 during which serum CRP was measured via a blood draw. After controlling for inflammation-related confounds (e.g., tobacco use, body mass index), adolescents' perceptions of parental SBS, but not peer support or general parental support, predicted lower CRP values at age 32 (b = -.92, SE = .34, p < .05). None of the support variables in early adulthood predicted CRP at 32 years. This study adds to a growing literature on relationships and health-related outcomes and provides the first evidence for a link between parental SBS in adolescence and a marker of inflammatory activity in adulthood.

8.
J Youth Adolesc ; 45(6): 1208-25, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26885828

RESUMO

Framed by expectancy-value theory (which posits that beliefs about and the subjective valuation of a domain predict achievement and decision-making in that domain), this study examined the relationships among teacher differential treatment and relevant math instruction on African American students' self-concept of math ability, math task value, and math achievement. These questions were examined by applying structural equation modeling to 618 African American youth (45.6 % female) followed from 7th to 11th grade in the Maryland Adolescent Development in Context Study. While controlling for gender and prior math achievement, relevant math instruction promoted and teacher differential treatment corroded students' math beliefs and achievement over time. Further, teacher discrimination undermined students' perceptions of their teachers, a mediating process under-examined in previous inquiry. These findings suggest policy and practice levers to narrow opportunity gaps, as well as foster math achievement and science, technology, engineering and math success.


Assuntos
Sucesso Acadêmico , Negro ou Afro-Americano/psicologia , Matemática , Racismo/psicologia , Professores Escolares/psicologia , Autoimagem , Adolescente , Aptidão , Feminino , Humanos , Estudos Longitudinais , Masculino , Maryland , Teoria Psicológica , Racismo/etnologia
9.
Int J Psychol ; 51(1): 78-82, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25684090

RESUMO

Based on the cross-cultural research linking individualism-collectivism and self-enhancement, this research examines regional pattern of self-enhancement in Ukraine. Broadly speaking, the western part of Ukraine is mainly Ukrainian speaking and historically oriented towards Europe, whereas Eastern Ukraine is mainly Russian speaking and historically oriented towards the Russian cultural sphere. We found self-enhancement on a "better than average" task to be higher in a Western Ukrainian sample compared to an Eastern Ukrainian sample, with differences in independent self-construals supporting assumed regional variation in individualism. However, the Muhammad Ali effect, the finding that self-enhancement is greater in the domain of morality than intelligence, was not replicated. The discussion focuses on the specific sources of this regional difference in self-enhancement, and reasons for why the Muhammad Ali effect was not found.


Assuntos
Características Culturais , Individualidade , População Branca/psicologia , Adulto , Comparação Transcultural , Europa (Continente) , Feminino , Humanos , Inteligência , Masculino , Princípios Morais , Personalidade , Federação Russa , Autorrelato , Inquéritos e Questionários , Traduções , Ucrânia
10.
Redox Biol ; 71: 103094, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38479221

RESUMO

Low-molecular-weight (LMW) thiols are produced in all living cells in different forms and concentrations. Glutathione (GSH), coenzyme A (CoA), bacillithiol (BSH), mycothiol (MSH), ergothioneine (ET) and trypanothione T(SH)2 are the main LMW thiols in eukaryotes and prokaryotes. LMW thiols serve as electron donors for thiol-dependent enzymes in redox-mediated metabolic and signaling processes, protect cellular macromolecules from oxidative and xenobiotic stress, and participate in the reduction of oxidative modifications. The level and function of LMW thiols, their oxidized disulfides and mixed disulfide conjugates in cells and tissues is tightly controlled by dedicated oxidoreductases, such as peroxiredoxins, glutaredoxins, disulfide reductases and LMW thiol transferases. This review provides the first summary of the current knowledge of structural and functional diversity of transferases for LMW thiols, including GSH, BSH, MSH and T(SH)2. Their role in maintaining redox homeostasis in single-cell and multicellular organisms is discussed, focusing in particular on the conjugation of specific thiols to exogenous and endogenous electrophiles, or oxidized protein substrates. Advances in the development of new research tools, analytical methodologies, and genetic models for the analysis of known LMW thiol transferases will expand our knowledge and understanding of their function in cell growth and survival under oxidative stress, nutrient deprivation, and during the detoxification of xenobiotics and harmful metabolites. The antioxidant function of CoA has been recently discovered and the breakthrough in defining the identity and functional characteristics of CoA S-transferase(s) is soon expected.


Assuntos
Antioxidantes , Compostos de Sulfidrila , Compostos de Sulfidrila/metabolismo , Antioxidantes/metabolismo , Transferases/metabolismo , Oxirredução , Glutationa/metabolismo , Oxirredutases/metabolismo , Dissulfetos/química
11.
J Behav Med ; 35(6): 581-90, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22113318

RESUMO

Current research indicates that racial discrimination is pervasive in the lives of African Americans. Although there are a variety of ways in which discrimination may contribute to health, one potentially important pathway is through its impact on substance use. Addressing the paucity of longitudinal research on this topic, the present study examined the influence of teacher discrimination on changes in substance use over time among African American adolescents and considered three dimensions of racial identity as moderators of this association (centrality, private regard, and public regard). Latent variable SEM analyses indicated that, on average, levels of discrimination were associated with increases in substance use across the high school years. However, public regard was found to moderate this association such that discrimination was less strongly associated with increases in substance use for individual who reported lower levels of public regard. The implications of these findings are discussed.


Assuntos
Negro ou Afro-Americano/psicologia , Usuários de Drogas/psicologia , Modelos Estatísticos , Racismo/psicologia , Autoimagem , Percepção Social , Adolescente , Comportamento do Adolescente/psicologia , Humanos , Estudos Longitudinais
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