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Facial and Body Emotion Recognition in InfancyOberst, Leah 01 January 2014 (has links)
Adults are experts at assessing emotions, an ability essential for appropriate social interaction. The present study, investigated this ability’s development, examining infants’ matching of facial and body emotional information.
In Experiment 1, 18 6.5-month-olds were familiarized to angry or happy bodies or faces. Those familiarized to bodies were tested with familiar and novel emotional faces. Those habituated to faces were tested with bodies. The 6.5-month-old infants exhibited a preference for the familiar emotion, matching between faces and bodies.
In Experiment 2, 18 6.5-month-olds were tested with faces and bodies displaying anger and sadness. Infants familiarized to faces showed a familiarity preference; Infants familiarized to bodies failed to discriminate. Thus, infants generalized from faces to bodies, but failed in the reverse. A follow-up study increased the duration of familiarization: 12 additional 6.5-month-olds were exposed to two-30s familiarizations with bodies, and tested with faces. Additional exposure induced matching of emotions.
In Experiment 3, 18 3.5-month-olds were tested using Experiment 1’s stimuli and methodology. The 3.5-month-old infants did not discriminate during test trials.
These results suggest 6.5-month-old infants are capable of matching angry, sad and happy faces and bodies. However, 3.5-month-olds are not, suggesting a developmental change between 3.5- and 6.5-months.
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Infant Development and Maternal Strategies in the Two Largest Lemurs: The Diademed Sifaka (Propithecus diadema) and the Indri (Indri indri).Weir, Jody Suzanne 22 August 2014 (has links)
At least half of the world’s primate species are currently threatened with extinction. Slow life histories combined with rapid habitat loss and hunting in recent years has heightened the extinction risk for many species, including the two largest extant lemurs, the diademed sifaka (Propithecus diadema) and the indri (Indri indri). Both species belong to the taxonomic family Indriidae, have similar adult weights, and occur in sympatry in certain areas of the montane rainforests of eastern Madagascar. Both species are adapted for folivory however I. indri spend considerably more time feeding on leaves than do P. diadema resulting in several energy-saving adaptations in I.indri. In this dissertation, I explore infant development and maternal strategies of these critically endangered primates with the goal of increasing our knowledge of reproduction and ontogeny in both species. Although previous studies have elucidated key differences in adult behaviour, there is a dearth of information on infants and lactating females in either of these two species. Between June and December of 2011 and 2012, I collected continuous time focal animal data, in Maromizaha forest, to examine behavioural patterns of 12 infants and their mothers from 0 – 33 weeks. In addition, I developed a framework to define and quantify the weaning process and facilitate comparisons across different species and studies. P. diadema infants developed feeding competency and independent locomotion faster than did I. indri infants however both species were consistently feeding independently more than they were suckling by week 20. The process of feeding ontogeny in I. indri was likely accelerated by coprophagy, as all infants of this species consumed their mother’s feces regularly from 10 – 15 weeks old. Lactating females of both species spent more time feeding in mid-lactation when maternal investment was the highest. The prolonged inter-birth interval in I. indri is suggested as another adaptation that reduces energetic expenditures. In addition, the protracted period of close contact with their mother may offer infant I. indri more time for social learning of the mother’s diet and the group song and for developing competency in vertical clinging and leaping without a tail for balance and support. / Graduate
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Stress, Depression, and the Mother-Infant Relationship Across the First YearJanuary 2014 (has links)
abstract: Postpartum depression (PPD) is a significant public health concern affecting up to half a million U.S. women annually. Mexican-American women experience substantially higher rates of PPD, and represent an underserved population with significant health disparities that put these women and their infants at greater risk for substantial psychological and developmental difficulties. The current study utilized data on perceived stress, depression, maternal parenting behavior, and infant social-emotional and cognitive development from 214 Mexican-American mother-infant dyads. The first analysis approach utilized a latent intercept (LI) model to examine how overall mean levels and within-person deviations of perceived stress, depressive symptoms, and maternal parenting behavior are related across the postpartum period. Results indicated large, positive between- and within-person correlations between perceived stress and depression. Neither perceived stress nor depressive symptoms were found to have significant between- or within-person associations with the parenting variables. The second analysis approach utilized an autoregressive cross-lagged model with tests of mediation to identify underlying mechanisms among perceived stress, postpartum depressive symptoms, and maternal parenting behavior in the prediction of infant social-emotional and cognitive development. Results indicated that increased depressive symptoms at 12- and 18-weeks were associated with subsequent reports of increased perceived stress at 18- and 24-weeks, respectively. Perceived stress at 12-weeks was found to be negatively associated with subsequent non-hostility at 18-weeks, and both sensitivity and non-hostility were found to be associated with infant cognitive development and social-emotional competencies at 12 months of age (52-weeks), but not with social-emotional problems. The results of the mediation analyses showed that non-hostility at 18- and 24-weeks significantly mediated the association between perceived stress at 12-weeks and infant cognitive development and social-emotional competencies at 52-weeks. The findings extend research that sensitive parenting in early childhood is as important to the development of cognitive ability, social behavior, and emotion regulation in ethnic minority cultures as it is in majority culture families; that maternal perceptions of stress may spillover into parenting behavior, resulting in increased hostility and negatively influencing infant cognitive and social-emotional development; and that symptoms of depressed mood may influence the experience of stress. / Dissertation/Thesis / Doctoral Dissertation Psychology 2014
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Concepções de mães, pais e educadoras sobre desenvolvimento infantil e gêneroVasconcelos, Dalila Castelliano 24 February 2017 (has links)
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Previous issue date: 2017-02-24 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / As of an early stage, interaction between adults and children is influenced by
gender questions. This is a relevant aspect of infant development, once gender conceptions by
adults may make it possible for girls and boys to hold different opportunities for
development. In the first childhood, two major direct socializing contexts take part of the
child’s life: the family, which is the primary socializing context, and the school. Considering
child development from a cultural perspective, this research focuses on identifying and
analyzing the conceptions by mothers, fathers, and educators of children aged two and three
years old concerning infant development and gender relationships in childhood. As many as
40 mothers - 20 of whom of girls, and 20 of boys - 40 fathers, distributed similarly, and 20
educators - ten from children’s public educational centers, and ten from private ones. Data
were analyzed with theoretical-methodological contributions from Bardin’s analysis content.
Outcomes signal that the conceptions on infant development by the participants have an
influence over caretaking strategies utilized, and over socialization goals presented by them.
Mothers, fathers and educators describe boys and girls antagonistically, inasmuch as they
state that girls are delicate, well-behaved, and enjoy girls’ plays, whereas boys are badlybehaved,
active, agitated, and enjoy boys’ plays. A total of 65% of mothers and fathers, and
25% of educators asserted that they use sexist directives for interaction with girls. In relation
to interaction with boys, this rate goes up to 95%, between mothers and fathers, and 65%
between educators, which leads to the conclusion that boys undergo more interferences in
their behavior than do the girls. The participants interfere with children’s actions and
delimitate which exclusive activities suit each sex when they handle with opposite-sex typical
toys and clothing items, and express behaviors most often accounted as usual for the opposite
sex, too. Parents stated that they do not interfere in their children’s choice to play with
children of the same sex, yet, by offering boys and girls distinct toys, besides providing a
stereotype in the way of playing, they will also contribute for sexual segregation among
children during plays. Such conceptions may be seen in intervention proposals targetting
infant development promotion, and more equitable gender relationships. / Desde muito cedo, a interação entre adultos e crianças é influenciada por
questões de gênero. Esse é um aspecto importante do desenvolvimento infantil, uma vez que
as concepções de gênero dos adultos podem possibilitar diferentes oportunidades de
desenvolvimento para meninas e meninos. Na primeira infância, dois grandes contextos
socializadores diretos fazem parte da vida da criança: a família, que é o contexto socializador
primário, e a escola. Considerando o desenvolvimento infantil a partir de uma perspectiva
cultural, esta pesquisa tem o objetivo de identificar e analisar as concepções de mães, pais e
educadoras de crianças de dois e três anos de idade a respeito do desenvolvimento infantil e
das relações de gênero na infância. Foram entrevistadas 40 mães - 20 de meninas e 20 de
meninos - 40 pais, com a mesma distribuição, e 20 educadoras - dez de centros de educação
infantil públicos e 10 de centros de educação infantil privados. Os dados foram analisados a
partir das contribuições teórico-metodológicas da análise de conteúdo de Bardin. Os
resultados indicam que as concepções sobre desenvolvimento infantil dos participantes
influenciam as estratégias de cuidado utilizadas e as metas de socialização apresentadas por
eles. Mães, pais e educadoras definem meninas e meninos de forma antagônica, porquanto
afirmam que as meninas são delicadas, disciplinadas e gostam de brincadeiras de meninas, e
que os meninos são indisciplinados, ativos, agitados e gostam de brincadeiras de meninos.
Um total de 65% de mães e pais de meninas e 25% das educadoras afirmaram que utilizam
diretivos sexistas na interação com meninas. Na interação com meninos, esse número se eleva
para 95%, entre mães e pais de meninos e 65% das educadoras, o que indica que os meninos
sofrem mais interferências em seu comportamento do que as meninas. Os participantes
interferem nas ações das crianças e delimitam o que são atividades exclusivas de cada sexo
quando as crianças manipulam brinquedos e roupas e acessórios considerados do sexo oposto
e expressam comportamentos também considerados do sexo oposto. Os pais afirmaram que
não interferem para que os filhos brinquem com crianças do mesmo sexo, entretanto, ao
oferecer brinquedos diferentes para meninas e meninos, além de propiciar uma esteriotipia na
forma de brincar, eles poderão contribuir para a segregação sexual entre as crianças durante
as brincadeiras. Tais concepções devem ser consideradas em propostas de intervenção que
visem à promoção do desenvolvimento infantil e relações de gênero mais equitativas.
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Atividade motora e o estado nutricional em lactentes hospitalizados com sibilancia recorrente agudizada / Motor function and nutritional status in hospitalized infants with recurrent acute wheezingNicacio, Siomara Lais de Souza Malta 25 February 2008 (has links)
Orientador: Antonio Fernando Ribeiro / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-11T03:12:37Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008 / Resumo: Com o objetivo de avaliar e correlacionar o estado nutricional e a atividade motora de Lactentes Sibilantes em processo de internação hospitalar, este estudo transversal foi realizado com uma coorte de 28 crianças com diagnóstico de Lactente Sibilante de 03 a 18 meses de vida internadas na enfermaria de pediatria do Hospital Estadual Sumaré/UNICAMP. Um segundo grupo de 28 lactentes saudáveis de escolas municipais de Ribeirão Preto e São Paulo foram igualmente avaliados com a finalidade de promover um pareamento com o primeiro grupo. O critério de pareamento foi o sexo e idade da criança. O período total do estudo compreendeu de 15 de agosto de 2005 a 04 de maio de 2007. Foram colhidos dados pessoais, antropometria e avaliação da função motora no momento da internação hospitalar para os Lactentes Sibilantes e durante período escolar para o grupo controle. A análise antropométrica foi feita por meio da medida de peso e comprimento da criança. Foi calculado o escore z do peso, altura e relação peso/altura e utilizadas as curvas do National Center of Health Statistics (NCHS, 2000). Para avaliação motora foi aplicada a Escala Alberta de Avaliação Motora (AIMS). Para obtenção do escore e percentil da escala, todas as posições assumidas pela criança foram registradas na folha de testes após observação da filmagem da movimentação espontânea nas posições prono, supino, sentado e em pé. Além da pesquisadora, foi solicitada a observação das filmagens por uma profissional especializada na área de neurologia infantil. Somente após a verificação e compatibilidade dos dois pareceres a pontuação foi registrada. Foram observadas a influência do z escore de peso e altura com relação ao escore da avaliação motora e escolaridade materna e nível socioeconômico não apresentaram influencia. Os resultados indicaram que houve atraso na função motora e aspecto nutricional deficitário no grupo de Lactentes Sibilantes / Abstract: The objective was to assess and correlate the motor function and nutritional status from hospitalized ¿wheezing¿ infants. A cross sectional study has been done in 28 children with ages from 03 to 18 months, during their treatment at the children¿s nursery in Sumaré State Hospital/Unicamp, which were diagnosed as ¿childhood wheezing syndromes¿. A second group of 28 healthy infants from Ribeirão Preto and São Paulo¿s schools was evaluated in order to be paired as control group. The criteria used for pairing was the gender and age. This study was conducted from August 15th, 2005 to May 4th, 2007. Personal information and anthropometrical data were collected, and the motor function was assessed. The anthropometrical analysis was performed by the measurements of weight and height of the children. The Alberta Infant Motor Scale (AIMS) was used to assess the child motor function. Every positions done by the children were registered on the protocol tests after the observation their spontaneous movements in prone, supine, sit and stand positions through recording of them. Another pediatric neurological professional observed the records too. The points were registered when both opinions were compatible. The influence of the z-score height and z-score weight variables was noted in the motor function score, and the mothers education level and socio-economic status presented no influence. A delay in the motor function development and poor nutritional conditions were observed in the wheezing infants population / Mestrado / Saude da Criança e do Adolescente / Mestre em Saude da Criança e do Adolescente
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Oportunidades de estimulação no domicílio e habilidade funcional de lactentes e pré-escolares com fatores de risco para alteração no desenvolvimentoSilva, Joselici da 13 December 2013 (has links)
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Previous issue date: 2013-12-13 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os fatores de risco biológicos, sociais e ambientais, e sua associação, aumentam a probabilidade do desenvolvimento motor ser comprometido. Os objetivos do presente estudo foram verificar a associação entre a habilidade funcional de mobilidade (HFM-PEDI) e as oportunidades de estímulos do ambiente domiciliar de lactentes e pré-escolares, com idade entre 18 e 42 meses, com fatores de risco, e averiguar se esta interação é afetada por fatores biológicos e socioeconômicos. Foi realizado um estudo transversal, com uma amostra aleatória de 112 participantes acompanhados em dois serviços de follow-up. Os instrumentos utilizados foram o Inventario de Avaliação Pediátrica de Incapacidade (PEDI) e o questionário Affordance in the Home Enviroment for Motor Development (AHEMD-SR). Foram realizadas estatísticas descritivas das variáveis estudadas e aplicado o Teste t de Student para verificar a significância da associação entre HFM-PEDI e as oportunidades de estímulos ambientais (AHEMD-SR), e com as variáveis moderadoras, nível socioeconômico (NSE), escolaridade materna, patologia e freqüência à creche. A análise de regressão linear múltipla foi utilizada a fim de investigar os possíveis efeitos das variáveis moderadoras na associação entre as oportunidades de estímulos no domicilio e os escores do HFM-PEDI. Entre os participantes, deste estudo, houve o predomínio de bom desempenho na HFM-PEDI (82,1%). Na classificação Total do AHEMD-SR, encontrou-se “nível médio” de presença de oportunidades de estimulação domiciliar em mais de dois terços dos participantes (74,1%), e um baixíssimo percentual (1,8%) apresentou “alto” nível de estímulos. Não foi observada associação significativa entre as variáveis HMF-PEDI e AHEMD-SR, mas a variabilidade da média para HFM-PEDI foi maior entre aqueles que tinham oportunidades insuficientes para o desenvolvimento motor nas dimensões variedade e motricidade grossa. Foi encontrada associação significativa (p = 0,004) apenas entre o desfecho (HFM-PEDI) e a presença de patologia. Participantes que apresentavam patologia tiveram menor média no escore normativo do PEDI. Na análise de regressão linear múltipla a variável patologia foi a única que apresentou associação significativa (p = 0,003), quando considerada a interação entre o ambiente, as variáveis moderadoras e o desfecho nas HFM-PEDI, uma vez que diminuiu em quase 8 pontos a média do escore normativo do PEDI. Conclui-se que não houve associação entre as oportunidades do ambiente domiciliar e a habilidade funcional de mobilidade de lactentes e pré-escolares com fatores de risco. A presença de patologia levou a desempenhos significativamente inferiores nas habilidades funcionais de mobilidade, sendo que esta variável impactou fortemente no desfecho resultante da interação do ambiente com o indivíduo. / Infant motor development is influenced by biological, social and environmental risk factors and their association. The aims of this study were to investigate the relationship between functional mobility skills (HFM-PEDI) of children aged 18-42 months and motor stimulus opportunities in their home environment, and to investigate if this relationship is affected by biological and socioeconomic factors. A transversal study was conducted with a random sample of 112 patients from two follow-up services. Instruments used were the Pediatric Evaluation Disability Inventory (PEDI) and the Affordance in the Home Enviroment for Motor Development (AHEMD-SR). Descriptive statistical analysis were carried out and Student t test was used to assess the association between HFM-PEDI and environmental stimulus (AHEMD-SR), and between HFM-PEDI and socioeconomic status (SES), mother's educational level, pathology and day-care attendance. Multiple linear regression analysis was carried out in order to investigate possible moderating effects of variables on the association between environmental stimulus opportunities and the scores of the HFM-PEDI. A predominance of good performance of functional mobility skills (82.1%) was observed among participants. More than two thirds of participants (74.1%) presented “average level” of environmental stimulus opportunities for Total AHEMD-SR classification, and the lowest percentage (1.8%) was observed to "high level” of stimulus. There was no significant association between HFM-PEDI and AHEMD-SR. Variability of the mean of HFM-PEDI was greater among participants who had insufficient opportunities to motor development on the variety of stimulation and gross motor dimensions. Findings revealed a significant association only between HFM-PEDI and presence of pathology (p = 0,004). Children with pathology had lower mean PEDI normative score. Multiple linear regression analysis revealed significant result for pathology in the interaction among environment, moderating variables and HFM-PEDI (p = 0.003). Presence of pathology decreased PEDI normative score in almost 8 points. It was concluded that there was no association between functional mobility skills of children with risk factors and motor stimulus opportunities in their home environment. Presence of pathology resulted in functional mobility skills significantly lower, and it strongly affected the HFM-PEDI resultant from the individual-environment interaction.
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Anatomo-functional correlates of visual and auditory development : insights on the ontogeny of face and speech processing lateralization / Les substrats anatomo-fonctionnels du développement auditif et visuel : perspectives sur l'ontogénie de la latéralisation du traitement de la parole et de la reconnaissance des visagesAdibpour, Parvaneh 17 October 2017 (has links)
Plusieurs fonctions cognitives sont latéralisées dans le cerveau humain adulte. Nous avons étudié l’origine des asymétries fonctionnelles chez les nourrissons, en évaluant les substrats neuronaux de reconnaissance des visages et des traitements du langage imbriqués dans les réseaux visuels et auditifs, grâce à la neuroimagerie non invasive (EEG et l’IRM de diffusion). Pour cela, nous avons étudié le développement fonctionnel et structurel de ces deux systèmes cérébraux au cours des six premiers mois postnataux. Nous avons observé que la vitesse des réponses visuelles était liée à la maturation des faisceaux de fibres de la matière blanche conduisant ces réponses, plus que l’âge des bébés, alors que la vitesse des réponses auditives doit dépendre d’un réseau de faisceaux de fibres et de régions corticales plus vaste. Parallèlement, nous avons étudié la latéralisation de la reconnaissance des visages grâce à un paradigme de discrimination des visages présentés dans chaque hémichamp. Nous avons observé que seul l'hémisphère droit pouvait discriminer les visages et que les informations pertinentes étaient transférées entre les deux hémisphères. Pour cibler la latéralisation du traitement du langage, nous avons étudié les réponses à des stimuli de la parole présentés de manière monaurale. Une comparaison entre un groupe de nourrissons avec une agénésie du corps calleux et un groupe contrôle a montré que les réponses à ces stimuli étaient transférées de façon asymétrique via le corps calleux. Cette asymétrie, facilitée vers l’hémisphère gauche, intervient probablement dans la latéralisation précoce du réseau du langage. L’ensemble de ces études mettent bien en évidence le potentiel de la neuroimagerie pour étudier le développement du cerveau et ces asymétries précoces. / Several cognitive functions such as face and speech processing are lateralized in the adult human brain. The ontogeny of these functional asymmetries is yet poorly understood. We aimed to evaluate the neural substrates of face and speech processing, nested in the visual and auditory networks using non-invasive neuroimaging techniques in infants. First, we studied how the functional and structural characteristics of these two brain systems change over the first postnatal semester. With EEG, we showed age-related decreases in the latency of brain responses and demonstrated that the speed of early visual responses is related to the maturation of underlying white matter tracts conducting them, as assessed with diffusion MRI. For the auditory system, our results suggested that the speed of responses may rely on maturation of more pathways and cortical regions. In parallel, we studied face processing lateralization using a discrimination paradigm of faces presented in each hemifield and observed that only the right hemisphere was able to discriminate between faces. Further evidence also suggested a transfer of face-relevant information across hemispheres. To study speech processing lateralization, we used a paradigm with monaural presentation of speech stimuli. A comparison between typical infants and infants with callosal agenesis, suggested an asymmetric transfer of auditory information across hemispheres, facilitated toward the left hemisphere, that might contribute to the lateralization of language early on. This thesis highlights the potential of neuroimaging techniques for the study of brain’s structural and functional development and of hemispheric asymmetries early on.
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Fetal alcohol spectrum disorder (FASD) from infancy to childhood: neuropsychological development and maternal depressionChetty-Makkan, Candice Maylene 16 July 2012 (has links)
Ph.D., Faculty of Health Sciences, University of the Witwatersrand, 2011 / Fetal Alcohol Spectrum Disorder (FASD) is a preventable cause of intellectual delay. Highly prevalent in South Africa, it has become a public health concern. Effective screening measures to identify women at risk of producing a FASD child is therefore important. This study postulated that a distinctive maternal profile may exist for mothers with FASD infants compared to a comparison group. Consequently, the study investigated the occurrence of maternal depression and its potential association with maternal risk factors and infant development respectively; differences in the profiles of mothers; as well as developmental differences in FASD and No FASD groups of children. An ex-post facto design was implemented, where the sample comprised of dyads that completed initial (infants 9-18 months) and follow-up (children 18-45 months) assessments. Severity of maternal depression (measured on the Beck Depression Inventory); maternal current mood states (measured on the Profile of Mood States) and infant developmental differences (measured with the Griffiths Mental Developmental Scales) were assessed. The results showed no distinct patterns in maternal depression in the FASD versus the No FASD groups; maternal depression was not significantly correlated with infant development; infants with FASD showed impaired overall development, with especially poor social adjustment; and all infants (FASD and No FASD) performed lower than the expected developmental norms. Maternal alcohol use was the only significant covariate associated with infant development. Identifying the predictors of high risk behaviour during pregnancy is complex, where prenatal alcohol exposure cannot be viewed in isolation from contextual factors, as limited resources, historical factors, cultural/community knowledge, a lack of stimulation and malnutrition prevail in many areas of South Africa. Profiling maternal predisposition to prenatal
alcohol use is essential in reducing the incidence of FASD in South Africa and implementing social skills intervention programs could aid the long-term adjustment of FASD infants.
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Interdisciplinary Study of Prenatal Polycyclic Aromatic Hydrocarbon Exposure and Mitochondrial ToxicityMcLarnan, Sarah January 2024 (has links)
The prenatal period of development is uniquely susceptible to lasting harmful health effects from exposure to environmental toxicants. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental pollutants which have a wide variety of associated health effects, including impaired neurodevelopment when exposure occurs in-utero. While a handful of mechanisms have been implicated in PAH neurodevelopmental toxicity, none fully resolve the intricate biological processes that contribute to these outcomes. Mitochondria are increasingly being studied as sensitive targets of many environmental toxicants including PAHs. Despite the known mitochondrial sensitivity to PAHs, and the role of mitochondrial functions in neurodevelopment, little research has been done to evaluate mitochondrial dysfunction as mechanism of PAH neurodevelopmental toxicity.
The work of this dissertation seeks to investigate a number of questions on this topic using a wide variety of techniques. We study exposure sources of individual PAHs, the relationship between prenatal PAH exposure constituents and mitochondrial functional outcomes and mitochondrial DNA copy number (mtDNAcn) in multiple biospecimens, including windows of exposure. We employ both epidemiological and experimental techniques, leveraging the advantages of one approach against the weakness of another to draw robust conclusions.
Chapter 2 begins by comprehensively studying the demographic and behavioral variables predictive of personal PAH exposure. We combined a significant amount of personal exposure data collected using silicone wristbands with prenatal questionnaires to identify variables most predictive of both exposure to individual PAH compounds and total exposure. This work revealed complex relationships between multiple parameters in the prediction of each individual PAH. We found demographic and socioeconomic variables to be the most common predictors of exposure, followed by behavior variables. This work provides the foundation to identify pathways to reduce exposure and protecting the most vulnerable populations.
In chapter 3, we describe two epidemiological studies conducted in Northern Manhattan birth cohorts. The first study uses data from the Columbia Center for Children’s Environmental Health (CCCEH) Fair Start cohort. We measured mitochondrial DNA copy number (mtDNAcn) in umbilical cord tissue, a novel biospecimen with unique utility due to its ease of acquisition and homogenous cellular composition. We measured individual exposure to 63 PAH compounds using silicone wristband samplers and analyze this data using both individual models and quantile G computation to estimate the overall mixture effect. We identified three compounds associated with mtDNAcn in individual models, and a positive association between the mixture of 19 compounds and mtDNAcn.
In the second study we expanded upon previous analyses in the CCCEH Mothers and Newborns cohort which had demonstrated an association between summed-total prenatal exposure to 8 carcinogenic PAHs and scores on the Bayley Scale of Infant Development-II at age 3. We used measures of mtDNAcn in umbilical cord blood to evaluate the role of mitochondrial toxicity in PAH neurodevelopment and improved upon prior studies by including adjustment for cell type composition. We utilized both traditional linear model approaches as well as quantile G computation to evaluate the mixture both as a sum-total and using newly developed mixture methods. We determined that while prenatal PAH exposure was negatively associated with umbilical cord blood mtDNAcn using mixtures methods mtDNAcn was not associated with neurodevelopment. The bidirectional effect of prenatal PAH exposure on mtDNAcn between these two studies reveals the complexity of mtDNAcn as a biomarker and the need for more direct measures of mitochondrial functions in the study of PAH neurodevelopmental toxicity.
Chapter 4 seeks to complement the epidemiological research with an experimental system. Using mouse preimplantation embryos, we measured the effect of exposure to an environmentally relevant mixture of PAHs on morphological development, superoxide production, mitochondria membrane potential, and mtDNAcn. We found exposure to low levels of a PAH mixture from days 2.5-3.5 post fertilization caused a significant decrease in healthy embryo morphology and a reduction in mtDNAcn. PAH exposure increased mitochondrial membrane potential under several dosing regimens while the effect on superoxide levels was variable and potentially mediated by changes in mitochondrial mass. As a whole these results indicate mitochondrial dysfunction as a result of low-level PAH exposure during the earliest periods of development with a window of heightened susceptibility immediately prior to implantation.
In chapter 5 we evaluate the relative mitochondrial potency of the 8 commonly studied carcinogenic PAHs and an environmental relevant mixture of those 8 compounds. Using human umbilical cord mesenchymal stem cells, we specifically study these effects in the context of prenatal development. Superoxide production, mitochondrial membrane potential, mitochondrial mass, cell death and mtDNAcn was quantified at 9 doses for each exposure. This data was used to fit dose response curves and determine relative potency of each exposure/outcome endpoint. We identified benzo[k]fluoranthene and chrysene among the most toxic compounds analyzed and noted differences between relative mitochondrial toxicity and carcinogenicity of these constituents emphasizing the need for continued research into the non-cancer endpoints of PAH exposure.
With the intentional comparable exposures and outcomes utilized in these studies comes the opportunity to make connections and draw conclusions across chapters to arrive at four major conclusion: (1) Demographic variables, not behavior, are most predictive of exposure to many PAH compounds (2) prenatal PAH exposure affects multiple measures of mitochondrial functions, (3) there is variability in the susceptibility during early development, and (4) the developmental mitochondrial toxicity of previously studied PAH compounds does not follow the same patterns of relative potency seen in carcinogenesis. This work provides significant insight into the impact of prenatal PAH exposure on mitochondrial functions while highlighting critical areas for further research. More studies are needed to fully understand the mechanisms and long-term effects of PAH exposure on early development, as well as to identify effective interventions to mitigate these risks.
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VALIDADE CONCORRENTE E CONCORDÂNCIA ENTRE OS TESTES ALBERTA INFANT MOTOR SCALE E BAYLEY SCALES OF INFANT DEVELOPMENT-THRID EDITION EM PREMATUROS BRASILEIROS COM TRÊS MESES DE IDADE GESTACIONAL CORRIGIDA / CONCURRENT VALIDITY AGREEMENT BETWEEN TESTS "ALBERTA INFANT MOTOR SCALE" AND "BAYLEY SCALES OF INFANT DEVELOPMENT-THRID EDITION" IN BRAZILIAN WITH PREMATURE THREE MONTHS CORRECTED GESTATIONAL AGE.Silva, Naíme Diane Sauaia Holanda 24 September 2010 (has links)
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Previous issue date: 2010-09-24 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Objective: To compare the results with the Scale of Alberta (Alberta Infant Motor
Scale), applied at three months of corrected gestational age (IGC), with those
Scale Bayley (Bayley Scales of Infant Development - 3rd edition) in premature
infants, discharged from the Neonatal Intensive Care Unit-NICU of University
Hospital Maternal Child Unit - UFMA.
Methods: We studied 42 premature infants in the outpatient clinics ("Follow up")
Unit, University Hospital Maternal Child Unit - UFMA between March and August
2009. In the study of concurrent validity and agreement of the 42 premature infants
at 3 months of IGC were assessed by AIMS and the motor scale of the Bayley
Scales of Infant Development, 3rd edition, using the correlation coefficient of
Pearson and the concordance test Bland & Altman to analyze the results.
Results: In the study of concurrent validity, correlation found between the two
scales was high (r = 0.86) and statistically significant (p <0.01) in the total
population of infants. In concordance analysis showed that most of the measures is
in the range between ± 1.96 standard deviation is thus the two tests agree.
Conclusion: The AIMS is a valid and consistent with the standard measures can
be recommended for evaluation of motor development of premature infants in the
population of public health in Brazil. / Objetivo: Comparar os resultados obtidos com a Escala de Alberta (Alberta Infant
Motor Scale), aplicada com três meses de idade gestacional corrigida (IGC), com
aqueles da Escala de Bayley (Bayley Scales of Infant Development - 3ª edição)
em lactentes nascidos prematuros, egressos da UTIN do Hospital Universitário
Unidade Materno Infantil - UFMA.
Métodos: Foram avaliados 42 lactentes nascidos prematuros no do Ambulatório
de Seguimento ( Follow up ) do Hospital Universitário Unidade Materno Infantil -
UFMA entre Março e Agosto de 2009. No estudo de validade concorrente e
concordância os 42 lactentes prematuros com 3 meses de IGC foram avaliados
pela AIMS e pela escala motora da Bayley Scales of Infant Development- 3ª
edição, utilizando-se o coeficiente de correlação de Pearson e o teste de
concordância Bland & Altman para analise dos resultados.
Resultados: No estudo de validade concorrente, a correlação encontrada entre as
duas escalas foi alta (r = 0,86) e estatisticamente significativa (p < 0,01) na
população total de lactentes. Na análise de concordância observou-se que a
maioria das medidas está na faixa compreendida entre ± 1,96 desvio padrão
sendo, portanto, os dois testes concordantes.
Conclusão: A AIMS é uma escala válida e concordante com as medidas padrões
podendo ser indicada para avaliação do desenvolvimento motor de lactentes
prematuros na população da rede publicam de saúde brasileira.
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