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1.
Environ Sci Technol ; 55(13): 9074-9086, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34132542

RESUMO

Children who live near coal-fired power plants are exposed to coal fly ash, which is stored in landfills and surface impoundments near residential communities. Fly ash has the potential to be released as fugitive dust. Using data collected from 263 children living within 10 miles of coal ash storage facilities in Jefferson and Bullitt Counties, Kentucky, USA, we quantified the elements found in nail samples. Furthermore, using principal component analysis (PCA), we investigated whether metal(loid)s that are predominately found in fly ash loaded together to indicate potential exposure to fly ash. Concentrations of several neurotoxic metal(loid)s, such as chromium, manganese, and zinc, were higher than concentrations reported in other studies of both healthy and environmentally exposed children. From PCA, it was determined that iron, aluminum, and silicon in fly ash were found to load together in the nails of children living near coal ash storage facilities. These metal(loid)s were also highly correlated with each other. Last, results of geospatial analyses partially validated our hypothesis that children's proximity to power plants was associated with elevated levels of concentrations of fly ash metal(loid)s in nails. Taken together, nail samples may be a powerful tool in detecting exposure to fly ash.


Assuntos
Cinza de Carvão , Centrais Elétricas , Criança , Carvão Mineral , Cinza de Carvão/análise , Poeira/análise , Humanos , Metais
2.
Appl Psychophysiol Biofeedback ; 39(3-4): 237-57, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25267414

RESUMO

Autism spectrum disorder (ASD) is a pervasive developmental disorder characterized by deficits in social interaction, language, stereotyped behaviors, and restricted range of interests. In previous studies low frequency repetitive transcranial magnetic stimulation (rTMS) has been used, with positive behavioral and electrophysiological results, for the experimental treatment in ASD. In this study we combined prefrontal rTMS sessions with electroencephalographic (EEG) neurofeedback (NFB) to prolong and reinforce TMS-induced EEG changes. The pilot trial recruited 42 children with ASD (~14.5 years). Outcome measures included behavioral evaluations and reaction time test with event-related potential (ERP) recording. For the main goal of this exploratory study we used rTMS-neurofeedback combination (TMS-NFB, N = 20) and waitlist (WTL, N = 22) groups to examine effects of 18 sessions of integrated rTMS-NFB treatment or wait period) on behavioral responses, stimulus and response-locked ERPs, and other functional and clinical outcomes. The underlying hypothesis was that combined TMS-NFB will improve executive functions in autistic patients as compared to the WTL group. Behavioral and ERP outcomes were collected in pre- and post-treatment tests in both groups. Results of the study supported our hypothesis by demonstration of positive effects of combined TMS-NFB neurotherapy in active treatment group as compared to control WTL group, as the TMS-NFB group showed significant improvements in behavioral and functional outcomes as compared to the WTL group.


Assuntos
Ondas Encefálicas/fisiologia , Transtornos Globais do Desenvolvimento Infantil/terapia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Neurorretroalimentação/métodos , Estimulação Magnética Transcraniana/métodos , Adolescente , Adulto , Criança , Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Feminino , Humanos , Masculino , Projetos Piloto , Resultado do Tratamento , Adulto Jovem
3.
Front Syst Neurosci ; 8: 134, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25147508

RESUMO

OBJECTIVES: Reports in autism spectrum disorders (ASD) of a minicolumnopathy with consequent deficits of lateral inhibition help explain observed behavioral and executive dysfunctions. We propose that neuromodulation based on low frequency repetitive Transcranial Magnetic Stimulation (rTMS) will enhance lateral inhibition through activation of inhibitory double bouquet interneurons and will be accompanied by improvements in the prefrontal executive functions. In addition we proposed that rTMS will improve cortical excitation/inhibition ratio and result in changes manifested in event-related potential (ERP) recorded during cognitive tests. MATERIALS AND METHODS: Along with traditional clinical behavioral evaluations the current study used ERPs in a visual oddball task with illusory figures. We compared clinical, behavioral and electrocortical outcomes in two groups of children with autism (TMS, wait-list group). We predicted that 18 session long course in autistic patients will have better behavioral and ERP outcomes as compared to age- and IQ-matched WTL group. We used 18 sessions of 1 Hz rTMS applied over the dorso-lateral prefrontal cortex in 27 individuals with ASD diagnosis. The WTL group was comprised of 27 age-matched subjects with ASD tested twice. Both TMS and WTL groups were assessed at the baseline and after completion of 18 weekly sessions of rTMS (or wait period) using clinical behavioral questionnaires and during performance on visual oddball task with Kanizsa illusory figures. RESULTS: Post-TMS evaluations showed decreased irritability and hyperactivity on the Aberrant Behavior Checklist (ABC), and decreased stereotypic behaviors on the Repetitive Behavior Scale (RBS-R). Following rTMS course we found decreased amplitude and prolonged latency in the frontal and fronto-central N100, N200 and P300 (P3a) ERPs to non-targets in active TMS treatment group. TMS resulted in increase of P2d (P2a to targets minus P2a to non-targets) amplitude. These ERP changes along with increased centro-parietal P100 and P300 (P3b) to targets are indicative of more efficient processing of information post-TMS treatment. Another important finding was decrease of the latency and increase of negativity of error-related negativity (ERN) during commission errors that may reflect improvement in error monitoring and correction function. Enhanced information processing was also manifested in lower error rate. In addition we calculated normative post-error treaction time (RT) slowing response in both groups and found that rTMS treatment was accompanied by post-error RT slowing and higher accuracy of responses, whereas the WTL group kept on showing typical for ASD post-error RT speeding and higher commission and omission error rates. CONCLUSION: RESULTS from our study indicate that rTMS improves executive functioning in ASD as evidenced by normalization of ERP responses and behavioral reactions (RT, accuracy) during executive function test, and also by improvements in clinical evaluations.

4.
J Sleep Res ; 13(3): 265-8, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15339262

RESUMO

Autism is a developmental disability characterized by severe deficits in social interaction and communication, and the presence of repetitive-ritualistic behaviors. Sleep problems are frequently reported by parents of children with autism with prevalence estimates of 44-83% for sleep disorders in this population. To better understand sleep in autism, we surveyed sleep problems in 210 children with autism using a Likert-based questionnaire for parent report. The most frequently reported sleep problems included difficulty in falling asleep, restless sleep, not falling asleep in own bed, and frequent wakenings. Least frequently reported sleep problems were sleep walking, morning headaches, crying during sleep, apnea, and nightmares. When surveys were divided into mental retardation (MR)/not MR categories, no significant differences were identified in frequencies of reported sleep problems except for waking at night which occurred much more frequently in the MR group. There was also no difference in sleep problems related to age of the child other than nocturnal enuresis. An association was noted between certain medical problems and sleep problems. Vision problems, upper respiratory problems, and runny nose were associated with decreased nighttime sleep. Vision problems, poor appetite, and poor growth were associated with increased nighttime waking. Poor appetite and poor growth were associated with decreased willingness to fall asleep. This study confirms a high prevalence of sleep problems reported by parents of children with autism and points to the need for more systematic research as an initial step in developing treatment strategies.


Assuntos
Transtorno Autístico/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Deficiência Intelectual/epidemiologia , Masculino , Índice de Gravidade de Doença , Transtornos do Sono-Vigília/diagnóstico , Inquéritos e Questionários
5.
Neuroimage ; 17(1): 61-76, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12482068

RESUMO

Previous structural and functional imaging studies suggest that the corticocerebellar-thalamic-cortical circuit is dysfunctional in schizophrenia. Accurate identification and volumetric measurement of cerebellar subregions are essential to the assessment of the cerebellum's role in healthy and disease states. Manual parcellation of the cerebellum on MR images was performed with the use of guide traces. Guide traces identified relevant fissures and borders in several planes, and their intersections with the primary tracing plane were used to maintain consistency and accuracy during the parcellation. The cerebellum was parcellated into right and left anterior lobes, superior posterior lobes, inferior posterior lobes, and corpus medullare. A systematic review of the final traces ensured their accuracy. An artificial neural network was trained using a novel landmark-warped method to help account for wide variability in structure size and location. Overlaps of the manually traced lobes (intersection/union) ranged from 0.78 to 0.85 and intraclass correlations (r2) ranged from 0.82 to 0.94. In a comparison of the semiautomated method with the manual method overlaps ranged from 0.83 to 0.88 and intraclass correlations ranged from 0.92 to 0.97. For two raters using the semiautomated method overlaps ranged from 0.83 to 0.88 and intraclass correlations ranged from 0.97 to 0.99. The semiautomated method was built on the groundwork of the manual method to produce more reliable results in a fraction of the time, making valid measurements possible on a large number of subjects.


Assuntos
Cerebelo/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Núcleos Cerebelares/anatomia & histologia , Interpretação de Imagem Assistida por Computador , Redes Neurais de Computação , Reprodutibilidade dos Testes , Software
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