RESUMO
Transmission of Zika virus (ZIKV) in the Americas was first confirmed in May 2015 in northeast Brazil. Brazil has had the highest number of reported ZIKV cases worldwide (more than 200,000 by 24 December 2016) and the most cases associated with microcephaly and other birth defects (2,366 confirmed by 31 December 2016). Since the initial detection of ZIKV in Brazil, more than 45 countries in the Americas have reported local ZIKV transmission, with 24 of these reporting severe ZIKV-associated disease. However, the origin and epidemic history of ZIKV in Brazil and the Americas remain poorly understood, despite the value of this information for interpreting observed trends in reported microcephaly. Here we address this issue by generating 54 complete or partial ZIKV genomes, mostly from Brazil, and reporting data generated by a mobile genomics laboratory that travelled across northeast Brazil in 2016. One sequence represents the earliest confirmed ZIKV infection in Brazil. Analyses of viral genomes with ecological and epidemiological data yield an estimate that ZIKV was present in northeast Brazil by February 2014 and is likely to have disseminated from there, nationally and internationally, before the first detection of ZIKV in the Americas. Estimated dates for the international spread of ZIKV from Brazil indicate the duration of pre-detection cryptic transmission in recipient regions. The role of northeast Brazil in the establishment of ZIKV in the Americas is further supported by geographic analysis of ZIKV transmission potential and by estimates of the basic reproduction number of the virus.
Assuntos
Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia , Zika virus/isolamento & purificação , América/epidemiologia , Número Básico de Reprodução , Brasil/epidemiologia , Variação Genética , Genoma Viral/genética , Humanos , Microcefalia/epidemiologia , Microcefalia/virologia , Epidemiologia Molecular , Filogeografia , Análise Espaço-Temporal , Zika virus/genética , Infecção por Zika virus/epidemiologiaRESUMO
OBJECTIVE: This simulation study investigated factors influencing sustained performance and fatigue during operation of multiple Unmanned Aerial Systems (UAS). The study tested effects of time-on-task and automation reliability on accuracy in surveillance tasks and dependence on automation. It also investigated the role of trait and state individual difference factors. BACKGROUND: Warm's resource model of vigilance has been highly influential in human factors, but further tests of its applicability to complex, real-world tasks requiring sustained attention are necessary. Multi-UAS operation differs from standard vigilance paradigms in that the operator must switch attention between multiple subtasks, with support from automation. METHOD: 131 participants performed surveillance tasks requiring signal discrimination and symbol counting with a multi-UAS simulation configured to impose low cognitive demands, for 2 hr. Automation reliability was manipulated between-groups. Five Factor Model personality traits were measured prior to performance. Subjective states were assessed with the Dundee Stress State Questionnaire. RESULTS: Performance accuracy on the more demanding surveillance task showed a vigilance decrement, especially when automation reliability was low. Dependence on automation on this task declined over time. State but not trait factors predicted performance. High distress was associated with poorer performance in more demanding task conditions. CONCLUSIONS: Vigilance decrement may be an operational issue for multi-UAS surveillance missions. Warm's resource theory may require modification to incorporate changes in information processing and task strategy associated with multitasking in low-workload, fatiguing environments. APPLICATION: Interface design and operator evaluation for multi-UAS operations should address issues including motivation, stress, and sustaining attention to automation.
Assuntos
Aeronaves , Nível de Alerta/fisiologia , Função Executiva/fisiologia , Fadiga Mental/fisiopatologia , Desempenho Psicomotor/fisiologia , Adolescente , Adulto , Automação , Simulação por Computador , Feminino , Humanos , Masculino , Sistemas Homem-Máquina , Personalidade/fisiologia , Angústia Psicológica , Adulto JovemRESUMO
BACKGROUND: Aberrant generation of eicosanoids is associated with asthma, but the evidence remains incomplete and its potential utility as biomarkers is unclear. Major eicosanoids in exhaled breath condensates (EBCs) were assessed as candidate markers for childhood asthma. METHODS: Ten exhaled eicosanoid species was evaluated using ELISA in the discovery phase, followed by prediction model-building and validation phases. RESULTS: Exhaled LTB4 , LTE4 , PGE2, and LXA4 showed significant difference between asthmatics (N = 60) and controls (N = 20). For validation, an expanded study population consisting of 626 subjects with asthma and 161 healthy controls was partitioned into a training subset to establish a prediction model and a test sample subset for validation. Receiver operating characteristic (ROC) analyses of the training subset revealed the level of exhaled LTB4 to be the most discriminative among all parameters, including FeNO, and a composite of exhaled LTB4 , LXA4 , together with FeNO and FEV1 , distinguishing asthma with high sensitivity and specificity. Further, the Youden index (J) indicated the cut point value of 0.598 for this composite of markers as having the strongest discriminatory ability (sensitivity = 85.2% and specificity = 83.6%). The predictive algorithm as "asthma classification ratio" was further validated in an independent test sample with sensitivity and specificity being 84.4% and 84.8%, respectively. CONCLUSIONS: In a pediatric study population in Taiwan, the levels of exhaled LTB4 , LTE4 , LXA4, and PGE2 in asthmatic children were significantly different from those of healthy controls, and the combination of exhaled LTB4 and LXA4 , together with FeNO and FEV1 , best characterized childhood asthma.
Assuntos
Asma/classificação , Asma/diagnóstico , Biomarcadores/análise , Algoritmos , Área Sob a Curva , Testes Respiratórios , Criança , Pré-Escolar , Dinoprostona/análise , Eicosanoides/análise , Feminino , Volume Expiratório Forçado , Humanos , Leucotrieno B4/análise , Leucotrieno E4/análise , Lipoxinas/análise , Masculino , Óxido Nítrico/análise , Curva ROC , Sensibilidade e EspecificidadeRESUMO
INTRODUCTION: Apart from individual small-scale outbreaks, infections with vancomycin-resistant enterococci are uncommon in Hong Kong. A major outbreak of vancomycin-resistant enterococci, however, occurred at a large tertiary hospital in 2013. We describe the successful control of this outbreak and share the lessons learned. METHODS: In 2013, there was an abnormal increase in the incidence of vancomycin-resistant enterococci carriage compared with baseline in multiple clinical departments at Queen Elizabeth Hospital. A multipronged approach was adopted that included a 10-week hospital-wide active screening programme, which aimed to identify and isolate hidden vancomycin-resistant enterococci carriers among all in-patients. The identified carriers were completely segregated in designated wards where applicable. Other critical infection control measures included directly observed hand hygiene and environmental hygiene. A transparent and open disclosure approach was adopted throughout the outbreak. RESULTS: The infection control measures were successfully implemented. The active screening of vancomycin-resistant enterococci was conducted between 30 September and 10 November 2013. A total of 7053 rectal swabs were collected from patients in 46 hospital wards from 11 departments. The overall carriage rate of vancomycin-resistant enterococci was 2.8% (201/7053). Pulsed-field gel electrophoresis showed a predominant outbreak clone. We curbed the outbreak and kept the colonisation of vancomycin-resistant enterococci among patients at a pre-upsurge low level. CONCLUSIONS: We report the largest cohesive effort to control spread of vancomycin-resistant enterococci in Hong Kong. Coupled with other infection control measures, we successfully controlled vancomycin-resistant enterococci to the pre-outbreak level. We have demonstrated that the monumental tasks can be achieved with meticulous planning, and thorough communication and understanding between all stakeholders.
Assuntos
Infecção Hospitalar/prevenção & controle , Infecções por Bactérias Gram-Positivas/prevenção & controle , Controle de Infecções/métodos , Resistência a Vancomicina , Enterococos Resistentes à Vancomicina/isolamento & purificação , Adulto , Idoso , Antibacterianos/farmacologia , Infecção Hospitalar/microbiologia , Surtos de Doenças , Eletroforese em Gel de Campo Pulsado , Fezes/microbiologia , Feminino , Infecções por Bactérias Gram-Positivas/microbiologia , Desinfecção das Mãos , Hong Kong/epidemiologia , Humanos , Tempo de Internação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Isolamento de Pacientes , Centros de Atenção TerciáriaAssuntos
COVID-19 , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Doenças do Jejuno , Jejuno , Isquemia Mesentérica , Tomografia Computadorizada por Raios X/métodos , COVID-19/complicações , COVID-19/fisiopatologia , COVID-19/terapia , Dissecação , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Gangrena/etiologia , Gangrena/patologia , Humanos , Doenças do Jejuno/diagnóstico , Doenças do Jejuno/etiologia , Doenças do Jejuno/fisiopatologia , Doenças do Jejuno/cirurgia , Jejuno/irrigação sanguínea , Jejuno/diagnóstico por imagem , Jejuno/patologia , Jejuno/cirurgia , Isquemia Mesentérica/sangue , Isquemia Mesentérica/patologia , Isquemia Mesentérica/fisiopatologia , Isquemia Mesentérica/virologia , Pessoa de Meia-Idade , Readmissão do Paciente , SARS-CoV-2/isolamento & purificação , Resultado do TratamentoRESUMO
The elliptical zone method (E-Zone) can be used to obtain reliable body volume data including total body volume and segmental volumes with inexpensive and portable equipment. The purpose of this research was to assess the accuracy of body volume data obtained from E-Zone by comparing them with those acquired from the 3D photonic scanning method (3DPS). 17 male participants with diverse somatotypes were recruited. Each participant was scanned twice on the same day by a 3D whole-body scanner and photographed twice for the E-Zone analysis. The body volume data acquired from 3DPS was regarded as the reference against which the accuracy of the E-Zone was assessed. The relative technical error of measurement (TEM) of total body volume estimations was around 3% for E-Zone. E-Zone can estimate the segmental volumes of upper torso, lower torso, thigh, shank, upper arm and lower arm accurately (relative TEM<10%) but the accuracy for small segments including the neck, hand and foot were poor. In summary, E-Zone provides a reliable, inexpensive, portable, and simple method to obtain reasonable estimates of total body volume and to indicate segmental volume distribution.
Assuntos
Antropometria/métodos , Tamanho Corporal , Imageamento Tridimensional , Adulto , Braço , Pé , Mãos , Humanos , Perna (Membro) , Masculino , Pessoa de Meia-Idade , Somatotipos , TroncoRESUMO
BACKGROUND: Physical, mental and financial barriers among persons with disabilities limit their access to healthier diet. The present study investigated the relationship between disabilities and nutrient intake among US adults. METHODS: Data originated from National Health and Nutrition Examination Survey 2007-2008 and 2009-2010 waves (n = 11,811). Five disability categories include activities of daily living (ADLs), instrumental activities of daily living (IADLs), leisure and social activities (LSAs), lower extremity mobility (LEM) and general physical activities (GPAs). Nutrient intakes from food and dietary supplements were calculated from 24-h dietary recalls. Adherence to dietary reference intakes and dietary guideline recommendations was compared between people with and without disabilities and across disability categories in the statistical analysis. RESULTS: GPAs, IADLs, LSAs, LEM and ADLs occupied 24.5%, 13.3%, 9.9%, 9.2% and 9.2% of US adults, respectively (not mutually exclusive). Only 42.3%, 11.3%, 63.8%, 47.7%, 48.7%, 9.7%, 48.7%, 90.7%, 21.7% and 4.7% of adults had saturated fat, fibre, cholesterol, vitamin A, vitamin C, vitamin D, calcium, iron, sodium and potassium intakes from food within recommended levels, respectively. Dietary supplement use moderately improved vitamin C, vitamin D and calcium intakes. People with disabilities were less likely to meet recommended levels on saturated fat, fibre (except GPAs), vitamin A (except GPAs), vitamin C (except GPAs), calcium and potassium intakes than persons without disability. Nutrient intake differed across disability categories, with ADLs least likely to meet recommended intakes. CONCLUSIONS: Interventions targeting persons with disabilities through nutrition education and financial assistance are warranted to promote healthy diet and reduce disparities.
Assuntos
Dieta , Pessoas com Deficiência , Avaliação Nutricional , Ingestão de Energia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos NutricionaisRESUMO
This study investigated the relationship between the specific immunoglobulin E (IgE) profile for 40 allergens using a novel microarray technique (BioIC) and fraction of exhaled nitric oxide (FeNO) in a population sample of 1321 children. Significant positive associations were found between FeNO and sensitization to mites (P < 0.001), animals (P = 0.001), cockroaches (P < 0.001), and foods (P = 0.042), and furthermore, between FeNO and the number of sensitizations (all P < 0.05) or the sum of specific IgE (all P ≤ 0.01) against the aforementioned allergen categories. Specifically, sensitization to the following allergens was significantly related to higher FeNO: Dermatophagoides pteronyssinus, Dermatophagoides farina, Blomia tropicalis, cat, German cockroach, Oriental cockroach, codfish, crab, shrimp, and cheese (all P ≤ 0.01). In conclusion, IgE sensitization to mites, pets, cockroaches, seafood, and cheese, respectively, is significantly associated with elevated FeNO levels in a dose-dependent fashion in children. Our results provide new evidence that sensitization to certain food allergens may contribute to prompt inflammation in the airways.
Assuntos
Expiração , Imunoglobulina E/imunologia , Óxido Nítrico/metabolismo , Adolescente , Alérgenos/classificação , Alérgenos/imunologia , Animais , Criança , Feminino , Humanos , Hipersensibilidade/epidemiologia , Hipersensibilidade/imunologia , Hipersensibilidade/metabolismo , Imunoglobulina E/sangue , Masculino , Estudos ProspectivosRESUMO
Disability awareness and competency trainings are an important component of addressing ableism and health equity in the health promotion context. This commentary describes our process of developing, implementing, and refining a disability competency training, the Inclusive Community Exercise Training, for community-based group exercise instructors. The training originated from a partnership between academic researchers, community organizations, and individuals with disabilities. After initial pilot testing, we used feedback from participants to enhance the training. To optimize successful dissemination of this training, we utilized the Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM) framework, which is widely used in public health. The revision process focused on generalizing content to suit a wider audience, utilizing an eLearning platform for dissemination, and optimizing interactivity to improve learning effectiveness. The commentary emphasizes the lessons learned and the significance of systematic program revision, considering diverse expertise, content tailoring, and the benefits of accessible eLearning platforms.
Assuntos
Conscientização , Pessoas com Deficiência , Promoção da Saúde , Humanos , Pessoas com Deficiência/educação , Projetos Piloto , Promoção da Saúde/métodos , Avaliação de Programas e Projetos de Saúde/métodos , Exercício Físico , Conhecimentos, Atitudes e Prática em SaúdeRESUMO
Cardioviruses (e.g., Theiler's murine encephalomyelitis virus [TMEV]) are members of the Picornaviridae family that cause myocarditis and encephalitis in rodents. Recently, several studies have identified human cardioviruses, including Saffold virus (SAFV) and a related virus named human TMEV-like cardiovirus (HTCV). At least eight cardiovirus genotypes are now recognized, with SAFV and most strains of HTCV belonging to genotypes 1 and 2, respectively; genotype 2 strains are the most common in the population. Although a genotype 3 cardiovirus has recently been cultured (SAFV-3), the genotype 1 and 2 cardioviruses have been difficult to propagate in vitro, hindering efforts to understand their seroprevalence and pathogenicity. Here we present the isolation and characterization of a genotype 2 human cardiovirus (HTCV-UC6). Notably, successful cultivation of HTCV-UC6 from stool required the addition of cytokine-blocking antibodies to interrupt downstream antiviral pathways. Unlike SAFV-3, HTCV-UC6 exhibited slow replication kinetics and demonstrated only a moderate cytopathic effect. Serologic assays revealed that 91% of U.S. adults carry antibodies to the genotype 2 cardioviruses, of which 80% generate neutralizing antibodies, in agreement with previous data showing that cardiovirus infection is widespread in humans. We also demonstrate an acute cardiovirus seroconversion event in a child with diarrhea and vomiting, thus reporting for the first time evidence linking cardiovirus infection to diarrheal disease in humans.
Assuntos
Infecções por Cardiovirus/epidemiologia , Cardiovirus/isolamento & purificação , Cardiovirus/fisiologia , Diarreia/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Cardiovirus/genética , Cardiovirus/crescimento & desenvolvimento , Infecções por Cardiovirus/virologia , Linhagem Celular , Efeito Citopatogênico Viral , Fezes/virologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , RNA Viral/genética , Análise de Sequência de DNA , Estudos Soroepidemiológicos , Estados Unidos/epidemiologia , Replicação Viral , Adulto JovemRESUMO
Difficulty in inhibition or cognitive control is a common and significant sequela of pediatric traumatic brain injury (TBI). The present study used functional MRI to examine one specific inhibitory function, interference control, in 11 adolescents, aged 12-16 years, (mean age, 15.7 years) with TBI who were at least 1 year postinjury and 11 age-matched typically developing control participants (TC) (mean age, 15.2 years). Participants completed a Counting Stroop task with 2 main conditions: (1) a neutral condition requiring the counting of animal words and (2) an interference condition in which mismatched number words were counted. Both TBI and TC adolescents activated similar networks of brain regions relevant to interference control, but the TBI group showed higher levels of activation relative to the TC group in multiple brain areas within this network, including predominantly right frontal and parietal regions. Findings of greater activation of the relevant neural network in the TBI group are consistent with recent fMRI findings using other interference control paradigms with individuals with a history of TBI.
Assuntos
Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Mapeamento Encefálico , Encéfalo/irrigação sanguínea , Imageamento por Ressonância Magnética , Matemática , Adolescente , Criança , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Tempo de Reação/fisiologiaRESUMO
A growing body of literature has documented evidence for emotion labeling (EL) deficits after traumatic brain injury (TBI); however, long-term effects of TBI on EL abilities, particularly among young children, are unclear. We investigated EL abilities and socio-emotional outcomes in 32 children with moderate-severe TBI, 23 with complicated-mild TBI, and 82 children with orthopedic injuries (OI), shortly after injury and at 18 months post-injury. All children were between 3:0 and 6:11 years of age at the time of injury. Repeated measures analyses indicated that all groups showed improved EL performance between acute and 18-month assessments, but that the moderate-severe TBI group improved at a slower rate than the OI group, so that the two groups showed significantly different performance at 18 months. Emotion labeling ability did not significantly contribute to the prediction of socio-emotional outcomes after controlling for pre-injury functioning. These results provide preliminary evidence of emerging EL deficits after early childhood TBI that are related to injury severity but that do not predict social and behavioral outcomes.
Assuntos
Sintomas Comportamentais/etiologia , Lesões Encefálicas/complicações , Lesões Encefálicas/psicologia , Deficiências do Desenvolvimento/etiologia , Emoções/fisiologia , Percepção Social , Adaptação Psicológica/fisiologia , Criança , Pré-Escolar , Transtornos Cognitivos/etiologia , Feminino , Escala de Coma de Glasgow , Humanos , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Valor Preditivo dos Testes , Escalas de Graduação PsiquiátricaRESUMO
OBJECTIVES: To identify mutations in the KAL1, the KAL2, and PROKR2/PROK2 genes and to characterize phenotypic features in 5 Chinese subjects with Kallmann Syndrome (KS) and 6 subjects with normosmic hypogonadotrophic hypogonadism (NHH) in Taiwan. DESIGN AND PATIENTS: Five unrelated males (age range 22-52 yr) with clinical manifestations of KS and 6 unrelated males (age range 24-47 yr) with NHH were analyzed. In addition, 5 relatives of KS subjects were also evaluated. Genomic DNA extraction, PCR, and DNA sequence analyses were performed using standard procedures. RESULTS: The 1st patient had a single missense mutation in his copy of the KAL1 gene, a TâG transversion in codon 134 that results in replacement of cysteine by gly cine. The 2nd affected subject had a single missense mutation in the KAL1 gene, a TâC transition in codon 163 that results in replacement of cysteine by arginine. The 3rd case was hemizygous for a nonsense mutation in codon 424 of exon 9 (c.CGAâTGA) of the KAL1 gene. This mutation predicts a markedly truncated protein. Two of the mutations (p.C134G and p.C163R) we identified in the KAL1 gene are novel. CONCLUSIONS: We identified 3 mutations, including 2 novel mutations, in the KAL1 gene in patients with KS in Taiwan. These data extend the variety of KAL1 gene mutations in KS and further define the role of the KAL1 protein in olfactory bulb development.
Assuntos
Povo Asiático/genética , Proteínas da Matriz Extracelular/genética , Síndrome de Kallmann/genética , Mutação de Sentido Incorreto , Proteínas do Tecido Nervoso/genética , Adulto , Estudos de Casos e Controles , Feminino , Hormônios Gastrointestinais/genética , Mutação em Linhagem Germinativa , Humanos , Síndrome de Kallmann/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto/fisiologia , Neuropeptídeos/genética , Bulbo Olfatório/diagnóstico por imagem , Radiografia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Receptores Acoplados a Proteínas G/genética , Receptores de Peptídeos/genética , Adulto JovemRESUMO
Psittacosis is a zoonotic infectious disease caused by the transmission of Chlamydia psittaci; it often presents as a pulmonary infection but rarely as disseminated disease. Because diagnoses of psittacosis are often underreported due to infrequent pathogen-specific testing, clinical metagenomic next-generation sequencing may be helpful to diagnose such an uncommon syndrome.
RESUMO
Lake mixing disrupts chemical and physical gradients that structure bacterial communities. A transplant experiment was designed to investigate the influence of post-mixing environmental conditions and biotic interactions on bacterial community composition. The experimental design was 3x2 factorial, where water was incubated from three different sources (epilimnion, hypolimnion, and mixed epilimnion and hypolimnion) at two different locations in the water column (epilimnion or hypolimnion). Three replicate mesocosms of each treatment were removed every day for 5 days for bacterial community profiling, assessed by automated ribosomal intergenic spacer analysis. There were significant treatment effects observed, and temperature was the strongest measured driver of community change (r=-0.66). Epilimnion-incubated communities changed more than hypolimnion-incubated. Across all treatments, we classified generalist, layer-preferential and layer-specialist populations based on occurrence patterns. Most classified populations were generalists that occurred in both strata, suggesting that communities were robust to mixing. In a network analysis of the mixed-inocula treatments, there was correlative evidence of inter-population biotic interactions, where many of these interactions involved generalists. These results reveal differential responses of bacterial populations to lake mixing and highlight the role of generalist taxa in structuring an emergent community-level response.
Assuntos
Bactérias/classificação , Água Doce/microbiologia , Microbiologia da Água , Bactérias/isolamento & purificação , Meio Ambiente , TemperaturaRESUMO
The present study is part of a larger project that seeks to identify factors that predict children's behavioral, social, and cognitive adaptation to epilepsy. Children with seizures are more likely to have internalizing and externalizing behavior problems than either healthy children or children with other chronic illnesses. The present research examines risk factors for behavior problems. Early temperament and neuropsychological functioning, specifically executive function and language abilities, are evaluated as unique and moderating predictors of adverse behavioral outcomes in 229 children with a first recognized seizure. Parents assessed temperament, children were administered neuropsychological tests, and teachers evaluated behavior 36 months after seizure onset. Results revealed that early temperament and neuropsychological functioning, specifically executive function, predicted behavioral outcomes 3 years after seizure onset.
Assuntos
Sintomas Comportamentais/etiologia , Sintomas Comportamentais/psicologia , Transtornos Cognitivos/etiologia , Convulsões/complicações , Temperamento , Adolescente , Fatores Etários , Lista de Checagem , Criança , Deficiências do Desenvolvimento/etiologia , Feminino , Humanos , Controle Interno-Externo , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Inventário de Personalidade , Convulsões/psicologia , Meio Social , Inquéritos e QuestionáriosRESUMO
Attentional deficits are common and significant sequelae of pediatric traumatic brain injury (TBI). However, little is known about how the underlying neural processes that support different components of attention are affected. The present study examined brain activation patterns using fMRI in a group of young children who sustained a TBI in early childhood (n = 5; mean age = 9.4), and a group of age-matched control children with orthopedic injuries (OI) (n = 8) during a continuous performance task (CPT). Four children in the TBI group had moderate injuries, and one had a severe injury. Performance on the CPT task did not differ between groups. Both TBI and OI children activated similar networks of brain regions relevant to sustained attention processing, but the TBI group demonstrated several areas of significantly greater activation relative to controls, including frontal and parietal regions. These findings of over-activation of the relevant attention network in the TBI group contrast with those obtained in imaging studies of Attention-Deficit/Hyperactivity Disorder where under-activation of the attention network has been documented. This study provides evidence that young children's brains function differently following a traumatic brain injury, and that these differences persist for years after the injury.
Assuntos
Atenção/fisiologia , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Mapeamento Encefálico , Encéfalo , Imageamento por Ressonância Magnética , Análise de Variância , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Encéfalo/fisiopatologia , Criança , Feminino , Escala de Coma de Glasgow , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Tempo de Reação/fisiologia , Análise de RegressãoRESUMO
To understand the behavior of (137)Cs in undisturbed soils after nuclear fallout deposition between the 1940s and 1980s, we investigated the speciation of (137)Cs in soils in forest and its adjacent grassland from a volcano and subalpine area in Taiwan. We performed sequential extraction of (137)Cs (i.e., fractions readily exchangeable, bound to microbial biomass, bound to Fe-Mn oxides, bound to organic matter, persistently bound and residual). For both the forest and grassland soils, (137)Cs was mainly present in the persistently bound (31-41%) and residual (22-62%) fractions. The proportions of (137)Cs labile fractions--bound to exchangeable sites, microbial biomass, Mn-Fe oxides, and organic matter--were lower than those of the recalcitrant fractions. The labile fractions in the forest soils were also higher than those in the grassland soils, especially in the volcanic soil. The results suggest that the labile form of (137)Cs was mostly transferred to the persistently bound and resistant fractions after long-term deposition of fallout. The readily exchangeable (137)Cs fraction was higher in soils with higher organic matter content or minor amounts of 2:1 silicate clay minerals.
Assuntos
Poaceae/crescimento & desenvolvimento , Poluentes Radioativos do Solo/análise , Solo/análise , Árvores/crescimento & desenvolvimento , Altitude , Biomassa , Radioisótopos de Césio/análise , Ecossistema , Geografia , Cinza Radioativa/análise , Microbiologia do Solo , Taiwan , Clima TropicalRESUMO
We determined the content of radiocesium ((137)Cs) and alkali metals in soils, plants (2 ferns, a shrub and moss) and rainwater collected in an undisturbed forest ecosystem. The (137)Cs activity and the isotopic ratio of (137)Cs/Cs in the samples were used to interpret the distribution and uptake of (137)Cs and the alkali metals in plants. As a whole, the (137)Cs in plants was assimilated together with K but was not dependent on Cs. Different adaptations of fern species collected in ecological niches cause them to have different (137)Cs/Cs ratios. Diplopterygium glaucum is distributed at the edges of the forest; it usually has shallow organic layers, and the root takes up more stable Cs from mineral layers, leading to lower (137)Cs/Cs ratios than that in the understory Plagiogyria formosana and Rhododendron formosanum species. The steady supply of stable Cs through the uptake by D. glaucum from deep soils may gradually dilute the (137)Cs concentration and thus explain the lower (137)Cs/Cs ratio in the fern samples. The (137)Cs is predicted to be proportional to the Cs content across plant species in the biological cycle once isotopic equilibrium is attained.