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1.
Proc Natl Acad Sci U S A ; 117(38): 23329-23335, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-31611402

RESUMO

The development of biological markers of aging has primarily focused on adult samples. Epigenetic clocks are a promising tool for measuring biological age that show impressive accuracy across most tissues and age ranges. In adults, deviations from the DNA methylation (DNAm) age prediction are correlated with several age-related phenotypes, such as mortality and frailty. In children, however, fewer such associations have been made, possibly because DNAm changes are more dynamic in pediatric populations as compared to adults. To address this gap, we aimed to develop a highly accurate, noninvasive, biological measure of age specific to pediatric samples using buccal epithelial cell DNAm. We gathered 1,721 genome-wide DNAm profiles from 11 different cohorts of typically developing individuals aged 0 to 20 y old. Elastic net penalized regression was used to select 94 CpG sites from a training dataset (n = 1,032), with performance assessed in a separate test dataset (n = 689). DNAm at these 94 CpG sites was highly predictive of age in the test cohort (median absolute error = 0.35 y). The Pediatric-Buccal-Epigenetic (PedBE) clock was characterized in additional cohorts, showcasing the accuracy in longitudinal data, the performance in nonbuccal tissues and adult age ranges, and the association with obstetric outcomes. The PedBE tool for measuring biological age in children might help in understanding the environmental and contextual factors that shape the DNA methylome during child development, and how it, in turn, might relate to child health and disease.


Assuntos
Epigenômica/métodos , Células Epiteliais/metabolismo , Mucosa Bucal/citologia , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Ilhas de CpG , Epigênese Genética , Feminino , Humanos , Lactente , Estudos Longitudinais , Masculino , Mucosa Bucal/metabolismo , Adulto Jovem
2.
Alcohol Clin Exp Res ; 43(5): 833-841, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30889291

RESUMO

BACKGROUND: Prenatal alcohol exposure (PAE) is linked to alterations of cerebral white matter, including volume and nonspecific diffusion magnetic resonance imaging (MRI) indices of microstructure in humans. Some animal models of PAE have demonstrated myelination deficiencies, but myelin levels have not yet been evaluated in individuals with PAE. Multiecho T2 MRI offers a quantitative method to estimate myelin water fraction (MWF; related to myelin content) noninvasively, which was used here to evaluate brain myelination in children with PAE. METHODS: Participants with PAE (n = 10, 6 females, mean age 13.9 years, range 7 to 18 years) and controls (n = 14, 11 females, mean age 13.2 years, range 9 to 16 years) underwent 3T MRI of the brain. T2 images (15 minutes acquisition for 32 echoes) were used to create MWF maps from which mean MWF was measured in 12 regions of interest (ROIs) including 8 in white matter and 4 in deep gray matter. RESULTS: As expected, across the combined sample, MWF was highest for major white matter tracts such as the internal capsule and genu/splenium of the corpus callosum (10 to 18%) while the caudate and putamen had MWF less than 5%. Mean MWF was similar across 11/12 brain white and gray matter regions for the PAE and control groups (L/R internal capsule, major forceps, putamen, caudate nucleus, L minor forceps, genu and splenium of corpus callosum). In the PAE group, MWF was positively correlated with age in the genu of corpus callosum and right minor forceps, notably 2 frontal tracts. CONCLUSIONS: Given comparable MRI-derived myelination fraction measures in PAE relative to controls, white matter alterations shown in other imaging studies, such as diffusion tensor imaging, may reflect microstructural anomalies related to axon caliber and density.


Assuntos
Encéfalo/diagnóstico por imagem , Transtornos do Espectro Alcoólico Fetal/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Bainha de Mielina/patologia , Substância Branca/diagnóstico por imagem , Adolescente , Encéfalo/metabolismo , Colúmbia Britânica/epidemiologia , Criança , Feminino , Transtornos do Espectro Alcoólico Fetal/epidemiologia , Transtornos do Espectro Alcoólico Fetal/metabolismo , Humanos , Masculino , Bainha de Mielina/metabolismo , Gravidez , Substância Branca/metabolismo
3.
BMC Public Health ; 19(1): 1746, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881876

RESUMO

BACKGROUND: Fetal Alcohol Spectrum Disorder (FASD) is characterized by physical and neurological abnormalities resulting from prenatal alcohol exposure. Though diagnosis may help improve patient outcomes, the diagnostic process can be costly. Subsequently, screening children suspected of FASD prior to diagnostic testing has been suggested, to avoid administering testing to children who are unlikely to receive a diagnosis. The present study set out to assess the cost-effectiveness of currently recommended FASD screening tools. METHODS: The screenings tools evaluated were chosen from Children's Healthcare Canada's National Screening Toolkit for Children and Youth Identified and Potentially Affected by FASD and include meconium testing of fatty acid ethyl esters (meconium testing) and the neurobehavioral screening tool (NST). An economic model was constructed to assess cost-effectiveness. One-way and probabilistic sensitivity analyses were conducted to assess the robustness of findings. Costs reflect 2017 Canadian dollars and the perspective is the public healthcare system. RESULTS: Both screening tools evaluated resulted in reduced costs and fewer diagnosed years of life than a no screening strategy in which all children suspected of FASD receive diagnostic testing. The model predicts that screening newborns with meconium testing results in a reduced cost of $89,186 per 100 individuals screened and 38 fewer diagnosed years of life by age 18, corresponding to an incremental cost-effectiveness ratio (ICER) of $2359. Screening children with the NST resulted in a reduced cost of $183,895 per 100 individuals screened and 77 fewer diagnosed years of life by age 18, corresponding to an ICER of $2390. CONCLUSION: Findings suggest that screening is associated with less use of healthcare recourses but also fewer years of life with an FASD diagnosis over a no screening strategy. Since diagnosis can be key to children receiving timely and appropriate health and educational services, cost-savings must be weighed against the fewer years of life with a diagnosis associated with screening.


Assuntos
Transtornos do Espectro Alcoólico Fetal/diagnóstico , Programas de Rastreamento/economia , Canadá , Criança , Análise Custo-Benefício , Humanos , Modelos Econômicos
4.
BMC Public Health ; 19(1): 845, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253131

RESUMO

BACKGROUND: Fetal alcohol spectrum disorder (FASD) is one of the most disabling potential outcomes of prenatal alcohol exposure. The population-based prevalence of FASD among the general population of Canada was unknown. The objective of this study was to determine the population-based prevalence of FASD among elementary school students, aged 7 to 9 years, in the Greater Toronto Area (GTA) in Ontario, Canada. METHODS: This screening study used a cross-sectional, observational design utilizing active case ascertainment, along with retrospective collection of prenatal alcohol exposure information. Data collection involved two phases. Phase I consisted of taking growth measurements, a dysmorphology examination, and obtaining a history of behavioral and/or learning problems. Phase II consisted of a neurodevelopmental assessment, maternal interview, and behavioral observations/ratings by parents/guardians. Final diagnostic screening conclusions were made by consensus by a team of experienced multidisciplinary experts during case conferences, using the 2005 Canadian guidelines for FASD diagnosis. The prevalence of FASD was estimated, taking into consideration the selection rate, which was used to account for students who dropped out or were lost to follow-up during each phase. Monte Carlo simulations were employed to derive the confidence interval (CI) for the point estimates. RESULTS: A total of 2555 students participated. A total of 21 cases of suspected FASD were identified. The prevalence of FASD was estimated to be 18.1 per 1000, or about 1.8%. Using a less conservative approach (sensitivity analysis), the prevalence of FASD was estimated to be 29.3 per 1000, or about 2.9%. Therefore, the population-based prevalence of FASD is likely to range between 2 and 3% among elementary school students in the GTA in Ontario, Canada. CONCLUSIONS: This study provides the first population-based estimate of the prevalence of FASD in Canada. The estimate is approximately double or possibly even triple previous crude estimates. FASD prevalence exceeds that of other common birth defects such as Down's syndrome, spina bifida, trisomy 18, as well as autism spectrum disorder in Canada. More effective prevention strategies targeting alcohol use during pregnancy, surveillance of FASD, and timely interventions and support to individuals with FASD and their families are urgently needed.


Assuntos
Transtornos do Espectro Alcoólico Fetal/epidemiologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Criança , Estudos Transversais , Feminino , Transtornos do Espectro Alcoólico Fetal/diagnóstico , Humanos , Masculino , Programas de Rastreamento , Ontário/epidemiologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Prevalência , Estudos Retrospectivos , Instituições Acadêmicas , Estudantes/estatística & dados numéricos
5.
Physiol Genomics ; 50(10): 862-875, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30118404

RESUMO

Preeclampsia, a hypertensive syndrome occurring in 3-5% of human pregnancies, has lifelong health consequences for fetuses. Cognitive ability throughout life is altered, and adult stroke risk is increased. One potential etiological factor for altered brain development is low concentrations of proangiogenic placental growth factor (PGF). Impaired PGF production may promote an antiangiogenic fetal environment during neural and cerebrovascular development. We previously reported delayed vascularization of the hindbrain, altered retinal vascular organization, and less connectivity in the circle of Willis in Pgf-/- mice. We hypothesized Pgf-/- mice would have impaired cognition and altered brain neuroanatomy in addition to compromised cerebrovasculature. Cognitive behavior was assessed in adult Pgf-/- and Pgf+/+ mice by four paradigms followed by postmortem high-resolution MRI of neuroanatomy. X-ray microcomputed tomography imaging investigated the three-dimensional cerebrovascular geometry in another cohort. Pgf-/- mice exhibited poorer spatial memory, less depressive-like behavior, and superior recognition of novel objects. Significantly smaller volumes of 10 structures were detected in the Pgf-/- compared with Pgf+/+ brain. Pgf-/- brain had more total blood vessel segments in the small-diameter range. Lack of PGF altered cognitive functions, brain neuroanatomy, and cerebrovasculature in mice. Pgf-/- mice may be a preclinical model for the offspring effects of low-PGF preeclampsia gestation.


Assuntos
Encéfalo/diagnóstico por imagem , Neuroanatomia , Fator de Crescimento Placentário/deficiência , Aprendizagem Espacial/fisiologia , Microtomografia por Raio-X/métodos , Animais , Vasos Sanguíneos/diagnóstico por imagem , Vasos Sanguíneos/embriologia , Encéfalo/irrigação sanguínea , Encéfalo/embriologia , Cognição , Feminino , Humanos , Masculino , Memória , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator de Crescimento Placentário/genética , Gravidez
6.
Biochem Cell Biol ; 96(2): 161-166, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29533680

RESUMO

Fetal alcohol spectrum disorder (FASD) is characterized by a combination of neurological, developmental, and congenital defects that may occur as a consequence of prenatal alcohol exposure. Earlier reports showed that large chromosomal anomalies may link to FASD. Here, we examined the prevalence and types of copy number variations (CNVs) in FASD cases previously diagnosed by a multidisciplinary FASD team in sites across Canada. We genotyped 95 children with FASD and 87 age-matched, typically developing controls on the Illumina Human Omni2.5 SNP (single nucleotide polymorphisms) array platform. We compared their CNVs with those of 10 851 population controls to identify rare CNVs (<0.1% frequency), which may include large unbalanced chromosomal abnormalities, that might be relevant to FASD. In 12/95 (13%) of the FASD cases, rare CNVs were found that impact potentially clinically relevant developmental genes, including the CACNA1H involved in epilepsy and autism, the 3q29 deletion disorder, and others. Our results show that a subset of children diagnosed with FASD have chromosomal deletions and duplications that may co-occur or explain the neurodevelopmental impairments in a diagnosed cohort of FASD individuals. Children suspected to have FASD with or without sentinel facial features of fetal alcohol syndrome and neurodevelopmental delays should potentially be evaluated by a clinical geneticist and possibly have genetic investigations as appropriate to exclude other etiologies.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 3/genética , Transtornos do Espectro Alcoólico Fetal/genética , Dosagem de Genes , Polimorfismo de Nucleotídeo Único , Criança , Pré-Escolar , Feminino , Humanos , Masculino
7.
Hum Brain Mapp ; 39(1): 72-88, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28960637

RESUMO

Prenatal alcohol exposure (PAE) is associated with reduced overall brain volume. Although this has been reported consistently across studies, the status of cortical thickness after PAE is more variable. The cortex is asymmetric in typical controls, but it is unclear whether the left and right counter parts of the cortical gray matter are unevenly influenced in postpartum brain development after PAE. Brain MRI was acquired in a newly recruited sample of 157 participants (PAE: N = 78, 5.5-18.9 years, 40 females and controls: N = 79, 5.8-18.5 years, 44 females) across four Canadian sites in the NeuroDevNet project. The PAE group had other confounds such as psychiatric co-morbidity, different living environment, and so on, not present in the control group. In agreement with previous studies, the volumes of all brain structures were reduced in PAE compared to controls, including gray and white matter of cerebrum and cerebellum, and all deep gray matter including the hippocampus, amygdala, thalamus, caudate, putamen, and pallidum. The PAE group showed reductions in global and regional cortical thickness, while the pattern and degree of cortical thickness asymmetry were preserved in PAE participants with the greatest rightward asymmetry in the lateral parietal lobe and the greatest leftward asymmetry in the lateral frontal cortex. This persistent asymmetry reflects that the homologous left and right cortical regions followed typical relative developmental patterns in the PAE group despite being thinner bilaterally than controls. Hum Brain Mapp 39:72-88, 2018. © 2017 Wiley Periodicals, Inc.


Assuntos
Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/crescimento & desenvolvimento , Transtornos do Espectro Alcoólico Fetal/diagnóstico por imagem , Adolescente , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/patologia , Criança , Pré-Escolar , Comorbidade , Feminino , Transtornos do Espectro Alcoólico Fetal/patologia , Lateralidade Funcional , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão
8.
Hum Brain Mapp ; 38(1): 444-456, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27622670

RESUMO

Prenatal alcohol exposure (PAE) can cause central nervous system dysfunction and widespread structural anomalies as detected by magnetic resonance imaging (MRI). This study focused on diffusion tensor imaging (DTI) of white matter in a large sample of PAE participants that allowed us to examine correlations with behavioral outcomes. Participants were confirmed PAE (n = 69, mean age = 12.5 ± 3.2 years) or typically developing control children (n = 67, mean age = 12.1 ± 3.2 years) who underwent brain MRI, eye movement tasks, and psychometric tests. A semi-automated tractography method extracted fractional anisotropy (FA) and mean diffusivity (MD) values from 15 white matter tracts. The PAE group displayed decreased FA compared with controls in multiple tracts including 3 corpus callosum regions, right corticospinal tract, and 3 left hemisphere tracts connecting to the frontal lobe (cingulum, uncinate fasciculus, and superior longitudinal fasciculus). Significant group by sex interactions were found for the genu, left superior longitudinal fasciculus, and the left uncinate, with females in the PAE group exhibiting lower FA compared with control females. Correlations were found between DTI and eye movement measures in the control group, but these same relationships were absent in the PAE group. In contrast, no correlations were found between DTI and any of the psychometric tests used in this study. These findings support the hypothesis that measures of eye movement control may be valuable functional biomarkers of the brain injury induced by PAE as these tasks reveal group differences that appear to be linked to deficits in white matter integrity in the brain. Hum Brain Mapp 38:444-456, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Imagem de Tensor de Difusão/métodos , Movimentos Oculares/fisiologia , Efeitos Tardios da Exposição Pré-Natal/diagnóstico por imagem , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Psicometria , Substância Branca/diagnóstico por imagem , Adolescente , Fatores Etários , Anisotropia , Atenção/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Inibição Psicológica , Masculino , Memória/fisiologia , Avaliação de Resultados em Cuidados de Saúde , Gravidez , Estatística como Assunto
9.
Neurobiol Dis ; 91: 83-93, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26951949

RESUMO

Maternal alcohol consumption during gestation can cause serious injury to the fetus, and may result in a range of physiological and behavioral impairments, including increased seizure susceptibility, that are collectively termed fetal alcohol spectrum disorder (FASD). The cellular mechanisms underlying increased seizure susceptibility in FASD are not well understood, but could involve altered excitatory coupling of neuronal populations mediated by gap junction proteins. We utilized a mouse model of the prenatal alcohol exposure (PAE) to study the expression pattern of connexin (Cx) major components of gap junctions, and pannexin proteins, which form membrane channels, in the brain of 2-3weeks old PAE and control postnatal offspring. PAE during the first trimester-equivalent period of pregnancy in mice resulted in significant up-regulation of Cx30 mRNA and Cx30 total protein in the hippocampus of PAE animals compared to age-matched controls. Surface level expression of both dimeric and monomeric Cx30 were also found to be significantly up-regulated in both hippocampus and cerebral cortex of PAE animals compared to age-matched controls. On the membrane surface, the fast migrating form of Cx43 was found to be up-regulated in the hippocampus of PAE mice. However, we did not see any up-regulation of the phosphorylated forms of Cx43 on the membrane surface. These results indicate that the expression and processing of astrocytic connexins (Cx30, Cx43) are up-regulated in the brain of PAE offspring, and these changes could play a role in the cerebral hyperexcitability observed in these animals.


Assuntos
Álcoois/farmacologia , Astrócitos/efeitos dos fármacos , Conexina 43/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Astrócitos/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Conexina 30/genética , Conexina 30/metabolismo , Conexina 43/genética , Modelos Animais de Doenças , Feminino , Junções Comunicantes/efeitos dos fármacos , Junções Comunicantes/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Gravidez
10.
Alcohol Clin Exp Res ; 40(11): 2351-2358, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27716964

RESUMO

BACKGROUND: Saccades are rapid eye movements that bring an image of interest onto the retina. Previous research has found that in healthy individuals performing eye movement tasks, the location of a previous visual target can influence performance of the saccade on the next trial. This rapid behavioral adaptation represents a form of immediate neural plasticity within the saccadic circuitry. Our studies have shown that children with fetal alcohol spectrum disorder (FASD) are impaired on multiple saccade measures. We therefore investigated these previous trial effects in typically developing children and children with FASD to measure sensory neural plasticity and how these effects vary with age and pathology. METHODS: Both typically developing control children (n = 102; mean age = 10.54 ± 3.25; 48 males) and children with FASD (n = 66; mean age = 11.85 ± 3.42; 35 males) were recruited from 5 sites across Canada. Each child performed a visually guided saccade task. Reaction time and saccade amplitude were analyzed and then assessed based on the previous trial. RESULTS: There was a robust previous trial effect for both reaction time and amplitude, with both the control and FASD groups displaying faster reaction times and smaller saccades during alternation trials (visual target presented on the opposite side to the previous trial). Children with FASD exhibited smaller overall mean amplitude and smaller amplitude selectively on alternation trials compared with controls. The effect of the previous trial on reaction time and amplitude did not differ across childhood and adolescent development. CONCLUSIONS: Children with FASD did not display any significant reaction time differences, despite exhibiting numerous deficits in motor and higher level cognitive control over saccades in other studies. These results suggest that this form of immediate neural plasticity in response to sensory information before saccade initiation remains intact in children with FASD. In contrast, the previous trial effect on amplitude suggests that the motor component of saccades may be affected, signifying differential vulnerability to prenatal alcohol exposure.


Assuntos
Transtornos do Espectro Alcoólico Fetal/fisiopatologia , Plasticidade Neuronal , Tempo de Reação , Movimentos Sacádicos , Adolescente , Estudos de Casos e Controles , Criança , Desenvolvimento Infantil , Pré-Escolar , Feminino , Humanos , Masculino
11.
Camb Q Healthc Ethics ; 25(4): 726-32, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27634723

RESUMO

Fetal alcohol spectrum disorder (FASD) is increasingly recognized as a growing public health issue worldwide. Although more research is needed on both the diagnosis and treatment of FASD, and a broader and more culturally diverse range of services are needed to support those who suffer from FASD and their families, both research and practice for FASD raise significant ethical issues. In response, from the point of view of both research and clinical neuroethics, we provide a framework that emphasizes the need to maximize benefits and minimize harm, promote justice, and foster respect for persons within a global context.


Assuntos
Ética em Pesquisa , Transtornos do Espectro Alcoólico Fetal , Temas Bioéticos , Assistência à Saúde Culturalmente Competente , Feminino , Transtornos do Espectro Alcoólico Fetal/diagnóstico , Transtornos do Espectro Alcoólico Fetal/terapia , Saúde Global , Redução do Dano/ética , Humanos , Gravidez
12.
Alcohol Clin Exp Res ; 38(1): 116-25, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23915298

RESUMO

BACKGROUND: Fetal alcohol spectrum disorder (FASD) is associated with a large number of cognitive and sensory-motor deficits. In particular, the accurate assessment of sensory-motor deficits in children with FASD is not always simple and relies on clinical assessment tools that may be coarse and subjective. Here we present a new approach: using robotic technology to accurately and objectively assess motor deficits of children with FASD in a center-out reaching task. METHODS: A total of 152 typically developing children and 31 children with FASD, all aged between 5 and 18 were assessed using a robotic exoskeleton device coupled with a virtual reality projection system. Children made reaching movements to 8 peripheral targets in a random order. Reach trajectories were subsequently analyzed to extract 12 parameters that had been previously determined to be good descriptors of a reaching movement, and these parameters were compared for each child with FASD to a normative model derived from the performance of the typically developing population. RESULTS: Compared with typically developing children, the children with FASD were found to be significantly impaired on most of the parameters measured, with the greatest deficits found in initial movement direction error. Also, children with FASD tended to fail more parameters than typically developing children: 95% of typically developing children failed fewer than 3 parameters compared with 69% of children with FASD. These results were particularly pronounced for younger children. CONCLUSIONS: The current study has shown that robotic technology is a sensitive and powerful tool that provides increased specificity regarding the type of motor problems exhibited by children with FASD. The high frequency of motor deficits in children with FASD suggests that interventions aimed at stimulating and/or improving motor development should routinely be considered for this population.


Assuntos
Transtornos do Espectro Alcoólico Fetal/diagnóstico , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Robótica/métodos , Terapia de Exposição à Realidade Virtual/métodos , Adolescente , Criança , Pré-Escolar , Feminino , Transtornos do Espectro Alcoólico Fetal/fisiopatologia , Humanos , Masculino , Estimulação Luminosa/métodos
13.
Neurotoxicol Teratol ; 101: 107320, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38199312

RESUMO

INTRODUCTION: Methylmercury (MeHg) is an environmental contaminant that is of particular concern in Northern Arctic Canadian populations. Specifically, organic mercury compounds such as MeHg are potent toxicants that affect multiple bodily systems including the nervous system. Developmental exposure to MeHg is a major concern, as the developing fetus and neonate are thought to be especially vulnerable to the toxic effects of MeHg. The objective of this study was to examine developmental exposure to low doses of MeHg and effects upon the adult central nervous system (CNS). The doses of MeHg chosen were scaled to be proportional to the concentrations of MeHg that have been reported in human maternal blood samples in Northern Arctic Canadian populations. METHOD: Offspring were exposed to MeHg maternally where pregnant Sprague Dawley rats were fed cookies that contained MeHg or vehicle (vehicle corn oil; MeHg 0.02 mg/kg/body weight or 2.0 mg/kg/body weight) daily, throughout gestation (21 days) and lactation (21 days). Offspring were not exposed to MeHg after the lactation period and were euthanized on postnatal day 450. Brains were extracted, fixed, frozen, and sectioned for immunohistochemical analysis. A battery of markers of brain structure and function were selected including neuronal GABAergic enzymatic marker glutamic acid decarboxylase-67 (GAD67), apoptotic/necrotic marker cleaved caspase-3 (CC3), catecholamine marker tyrosine hydroxylase (TH), immune inflammatory marker microglia (Cd11b), endothelial cell marker rat endothelial cell antigen-1 (RECA-1), doublecortin (DCX), Bergmann glia (glial fibrillary acidic protein (GFAP)), and general nucleic acid and cellular stains Hoechst, and cresyl violet, respectively. Oxidative stress marker lipofuscin (autofluorescence) was also assessed. Both male and female offspring were included in analysis. Two-way analysis of variance (ANOVA) was utilized where sex and treatment were considered as between-subject factors (p* <0.05). ImageJ was used to assess immunohistochemical results. RESULTS: In comparison with controls, adult rat offspring exposed to both doses of MeHg were observed to have (1) increased GAD67 in the cerebellum; (2) decreased lipofuscin in the locus coeruleus; and (3) decreased GAD67 in the anterior CA1 region. Furthermore, in the substantia nigra and periaqueductal gray, adult male offspring consistently had a larger endothelial cell and capillary perimeter in comparison to females. The maternal high dose of MeHg influenced RECA-1 immunoreactivity in both the substantia nigra and periaqueductal gray of adult rat offspring, where the latter neuronal region also showed statistically significant decreases in RECA-1 immunoreactivity at the maternal low dose exposure level. Lastly, males exposed to high doses of MeHg during development exhibited a statistically significant increase in the perimeter of endothelial cells and capillaries (RECA-1) in the cerebellum, in comparison to male controls. CONCLUSION: Findings suggest that in utero and early postnatal exposure to MeHg at environmentally relevant doses leads to long-lasting and selective changes in the CNS. Exposure to MeHg at low doses may affect GABAergic homeostasis and vascular integrity of the CNS. Such changes may contribute to neurological disturbances in learning, cognition, and memory that have been reported in epidemiological studies.


Assuntos
Compostos de Metilmercúrio , Efeitos Tardios da Exposição Pré-Natal , Gravidez , Ratos , Animais , Masculino , Feminino , Humanos , Compostos de Metilmercúrio/toxicidade , Ratos Sprague-Dawley , Glutamato Descarboxilase/metabolismo , Glutamato Descarboxilase/farmacologia , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Capilares/metabolismo , Células Endoteliais/metabolismo , Lipofuscina/metabolismo , Lipofuscina/farmacologia , Canadá , Cerebelo , Mesencéfalo/metabolismo , Peso Corporal
14.
Biomolecules ; 14(5)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38785976

RESUMO

Fetal Alcohol Spectrum Disorder (FASD) is a common neurodevelopmental disorder that affects an estimated 2-5% of North Americans. FASD is induced by prenatal alcohol exposure (PAE) during pregnancy and while there is a clear genetic contribution, few genetic factors are currently identified or understood. In this study, using a candidate gene approach, we performed a genetic variant analysis of retinoic acid (RA) metabolic and developmental signaling pathway genes on whole exome sequencing data of 23 FASD-diagnosed individuals. We found risk and resilience alleles in ADH and ALDH genes known to normally be involved in alcohol detoxification at the expense of RA production, causing RA deficiency, following PAE. Risk and resilience variants were also identified in RA-regulated developmental pathway genes, especially in SHH and WNT pathways. Notably, we also identified significant variants in the causative genes of rare neurodevelopmental disorders sharing comorbidities with FASD, including STRA6 (Matthew-Wood), SOX9 (Campomelic Dysplasia), FDG1 (Aarskog), and 22q11.2 deletion syndrome (TBX1). Although this is a small exploratory study, the findings support PAE-induced RA deficiency as a major etiology underlying FASD and suggest risk and resilience variants may be suitable biomarkers to determine the risk of FASD outcomes following PAE.


Assuntos
Transtornos do Espectro Alcoólico Fetal , Tretinoína , Humanos , Feminino , Tretinoína/metabolismo , Transtornos do Espectro Alcoólico Fetal/genética , Transtornos do Espectro Alcoólico Fetal/metabolismo , Gravidez , Masculino , Predisposição Genética para Doença , Sequenciamento do Exoma
15.
Alcohol Clin Exp Res ; 37(9): 1499-507, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23551175

RESUMO

BACKGROUND: Eye movement tasks provide a simple method for inferring structural or functional brain deficits in neurodevelopmental disorders. Oculomotor control is impaired in children with fetal alcohol spectrum disorder (FASD), yet the neuroanatomical substrates underlying this are not known. Regions of white matter have been shown by diffusion tensor imaging (DTI) to be different in FASD and thus may play a role in the delayed saccadic eye movements. The objective of this study was to correlate oculomotor performance with regional measures of DTI-derived white matter anisotropy in children with FASD. METHODS: Fourteen children (8 to 13 years) with FASD were recruited for oculomotor assessment and DTI. Eye movement control was evaluated using the pro- and antisaccade tasks, in which subjects look at (prosaccade) or away from (antisaccade) a peripheral target. Saccadic reaction time (SRT; time for subjects to move their eyes after the target appears) and direction errors (saccades made in the incorrect direction relative to the instruction) were measured and correlated to fractional anisotropy (FA) on a voxel-by-voxel basis across the whole brain white matter. RESULTS: A significant positive correlation was observed between antisaccade SRT and FA in a large cluster containing anterior and posterior sections of the corpus callosum just to the right of the midline; prosaccade SRT and FA correlated positively in the genu of the corpus callosum and the right inferior longitudinal fasciculus (ILF), and correlated negatively in the left cerebellum. CONCLUSIONS: The negative correlation for prosaccade SRT and cerebellum demonstrated that individuals with slower reaction times had lower FA values relative to their faster responding counterparts, a finding that implicates cerebellar dysfunction as a significant contributor to deficits in oculomotor control. The higher FA in the corpus callosum and ILF corresponding to longer reaction times for both pro- and antisaccade was opposite to what was expected, but nonetheless implies that altered brain structure in these regions underlies deficits in oculomotor control.


Assuntos
Imagem de Tensor de Difusão/métodos , Transtornos do Espectro Alcoólico Fetal/diagnóstico , Transtornos do Espectro Alcoólico Fetal/fisiopatologia , Desempenho Psicomotor/fisiologia , Tempo de Reação/fisiologia , Movimentos Sacádicos/fisiologia , Adolescente , Criança , Estudos de Coortes , Feminino , Transtornos do Espectro Alcoólico Fetal/metabolismo , Humanos , Masculino , Estimulação Luminosa/métodos
16.
Alcohol Clin Exp Res ; 37(9): 1491-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23578065

RESUMO

BACKGROUND: Prenatal exposure to alcohol is a major, preventable cause of neurobehavioral dysfunction in children worldwide. The measurement and quantification of saccadic eye movements is a powerful tool for assessing sensory, motor, and cognitive function. The quality of the motor process of an eye movement is known as saccade metrics. Saccade accuracy is 1 component of metrics, which to function optimally requires several cortical brain structures as well as an intact cerebellum and brain-stem. The cerebellum has frequently been reported to be damaged by prenatal alcohol exposure. This study, therefore, tested the hypothesis that children with fetal alcohol spectrum disorder (FASD) will exhibit deficits in the accuracy of saccades. METHODS: A group of children with FASD (n = 27) between the ages of 8 and 16 and typically developing control children (n = 27) matched for age and sex, completed 3 saccadic eye movement tasks of increasing difficulty. Eye movement performance during the tasks was captured using an infrared eye tracker. Saccade metrics (e.g., velocity, amplitude, accuracy) were quantified and compared between the 2 groups for the 3 different tasks. RESULTS: Children with FASD were more variable in saccade endpoint accuracy, which was reflected by statistically significant increases in the error of the initial saccade endpoint and the frequency of additional, corrective saccades required to achieve final fixation. This increased variability in accuracy was amplified when the cognitive demand of the tasks increased. Children with FASD also displayed a statistically significant increase in response inhibition errors. CONCLUSIONS: These data suggest that children with FASD may have deficits in eye movement control and sensory-motor integration including cerebellar circuits, thereby impairing saccade accuracy.


Assuntos
Transtornos do Espectro Alcoólico Fetal/diagnóstico , Transtornos do Espectro Alcoólico Fetal/fisiopatologia , Desempenho Psicomotor/fisiologia , Movimentos Sacádicos/fisiologia , Adolescente , Criança , Feminino , Humanos , Masculino , Estimulação Luminosa/métodos
17.
Front Neurosci ; 17: 1176695, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37415615

RESUMO

Background: Aggression exhibited by children and youth with Fetal Alcohol Spectrum Disorder (FASD) toward family members is a major cause of stress and anxiety for caregivers, but relatively little attention has been directed toward designing interventions specific to this phenomenon. In light of the serious negative impact of this issue for families, a scoping review was undertaken to summarize the evidence available on psychosocial interventions that may mitigate the frequency and severity of aggression exhibited by children and youth with FASD toward family members. Methods: This review was designed using PRISMA-SCR and JBI scoping review guidelines. Three databases were searched in August 2021: EMBASE, PsychINFO, and Medline. Results: A total of 1,061 studies were imported for screening with only five studies meeting full eligibility criteria. None of the interventions were aimed at specifically targeting aggression and instead reported on broader constructs of externalizing behaviors such as hyperactivity. The interventions were limited to school-aged children. Studies reported primarily on child outcomes while only one reported on family related outcomes. Conclusion: Following from this review of the literature, we argue that aggression is a related but separate construct from other behavioral problems most frequently targeted by parenting interventions. Given the often dire consequence of aggression displayed by children and youth with FASD and the limited number of studies, there is an urgent need for research on how to support families to manage this specific type of behavior in this population.

18.
Front Health Serv ; 3: 1160217, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37425993

RESUMO

Introduction: Developmental delay affects approximately 1 in 4 children under 6 years old. Developmental delay can be detected using validated developmental screening tools, such as the Ages and Stages Questionnaires. Following developmental screening, early intervention can occur to address and support any developmental areas of concern. Frontline practitioners and supervisors must be trained and coached to organizationally implement developmental screening tools and early intervention practice. No prior work has qualitatively investigated the barriers and facilitators to implementing developmental screening and early intervention in Canadian organizations from the perspectives of practitioners and supervisors who have completed a specialized training and coaching model. Methods and Results: Following semi-structured interviews with frontline practitioners and supervisors, thematic analysis identified four themes: cohesive networks support implementation efforts, implementation success is dependent on shared perspectives, established organizational policies increase implementation opportunities, and COVID-19 guidelines create organizational challenges. Each theme encompasses sub-themes that describe implementation facilitators: strong implementation context, multi-level multi-sectoral collaborative partnerships, adequate and collective awareness, knowledge, and confidence, consistent and critical conversations, clear protocols and procedures, and accessibility to information, tools, and best practice guidelines. Discussion: The outlined barriers and facilitators fill a gap in implementation literature by informing a framework for organization-level implementation of developmental screening and early intervention following training and coaching.

19.
Behav Pharmacol ; 23(1): 105-12, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22157142

RESUMO

The objective of this study was to test the hypothesis that prenatal exposure to ethanol, through maternal consumption of an aqueous ethanol solution, induces neurobehavioral deficits and increases ethanol preference in offspring. Pregnant Dunkin-Hartley-strain guinea pigs were given 24-h access to an aqueous ethanol solution (5%, v/v) sweetened with sucralose (1 g/l), or water sweetened with sucralose (1 g/l), throughout gestation. Spontaneous locomotor activity was measured in the offspring on postnatal day (PD) 10. The offspring underwent either ethanol preference testing using a two-bottle-choice paradigm beginning on PD 40 or Morris water maze testing using a hidden moving platform design beginning on PD 60. Maternal consumption of a 5% (v/v) ethanol solution (average daily dose of 2.3±0.1 g of ethanol/kg maternal body weight; range: 1.8-2.8 g/kg) decreased offspring birth weight, increased spontaneous locomotor activity, and increased preference for an aqueous ethanol solution. In the Morris water maze test, sucralose-exposed offspring decreased escape latency on the second day of testing, whereas the ethanol-exposed offspring showed no improvement. These data demonstrate that moderate maternal consumption of ethanol produces hyperactivity, enhances ethanol preference, and impairs learning and memory in guinea pig offspring.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Etanol/toxicidade , Feto/efeitos dos fármacos , Animais , Feminino , Cobaias , Troca Materno-Fetal , Aprendizagem em Labirinto/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Gravidez
20.
Appl Neuropsychol Child ; 11(4): 691-701, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34155949

RESUMO

Children with prenatal alcohol exposure (PAE) experience a range of adverse outcomes that impact multiple domains of functioning, including cognitive, physical, mental health, behavioral, social-emotional, communication, and learning. To inform tailored clinical intervention, the current study examined the relation between caregiver-reported cognitive skills (executive function; EF) and adaptive functioning. The study conducted a secondary analyses of data provided by caregivers of 87 children and adolescents (aged 5-18 years, M = 11.7; 52% male) with confirmed PAE, including a subset (n = 70) with Fetal Alcohol Spectrum Disorder (FASD), who reported on their child's EF (Behavior Rating Inventory of Executive Function) and adaptive function (Adaptive Behavior Assessment System, 2nd Edition) skills. Findings from the current study showed that caregivers reported significantly poorer EF and adaptive functioning skills for children with PAE as compared to normative samples. Poorer behavior regulation skills were associated with all aspects of adaptive functioning (i.e., practical, conceptual, and social skills). Specifically, shifting skills emerged as the best predictor of adaptive functioning among children with PAE. These results highlight the possibility that targeting particular EF domains among individuals with PAE may benefit behavior regulation, which may also extend to adaptive skills. This highlights the need to develop EF interventions for children and adolescents who have been prenatally exposed to alcohol.


Assuntos
Transtornos do Espectro Alcoólico Fetal , Efeitos Tardios da Exposição Pré-Natal , Adaptação Psicológica , Adolescente , Criança , Comunicação , Função Executiva , Feminino , Humanos , Masculino , Gravidez
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