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1.
Clin Microbiol Infect ; 26(5): 637-642, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31499179

RESUMO

OBJECTIVES: The 2018 measles outbreak in Israel affected >2000 people in Jerusalem. The aim of the study was to describe clinical features and complications of hospitalized measles patients in Jerusalem, as related to age group and risk factors. METHODS: All individuals hospitalized with measles in the three main hospitals in Jerusalem during March 2018 to February 2019 were included. Demographic, clinical and laboratory data were analysed. RESULTS: Of 161 hospitalized individuals, 86 (53.4%) were <5 years old, 16 (10%) were ≥5 years but <20 years old, and 59 (36.6%) were ≥20 years old. Most, 114/135 (85%), were unvaccinated. Immunocompromised state was identified in 12/161 (7.5%) patients, 20/161 (12.4%) had other underlying co-morbidities, and four were pregnant. Hypoxaemia on admission was a common finding in all age groups. Hepatitis was more common among adults ≥20 years old (33/59, 59%). Measles-related complications were noted in 95/161 (59%) patients, and included pneumonia/pneumonitis (67/161, 41.6%), which was more common in young (<5 years) children, diarrhoea (18/161, 11.2%), otitis (18/161, 11.2%), and neurological complications (6/161, 3.7%)-the latter occurring more frequently in the 5- to 20-year age group. Two of the 12 immunocompromised patients died of measles-related complications. A high re-admission rate (19/161, 11.8%) within 3 months was documented among hospitalized measles patients. CONCLUSION: The burden of hospitalization, as well as the high rate of short- and long-term complications observed in hospitalized patients, underscore the importance of maintaining a high measles vaccine coverage, with enhanced targeting of unvaccinated population pockets.


Assuntos
Surtos de Doenças , Hospitalização/estatística & dados numéricos , Sarampo/complicações , Sarampo/epidemiologia , Surtos de Doenças/prevenção & controle , Surtos de Doenças/estatística & dados numéricos , Feminino , Humanos , Israel/epidemiologia , Masculino , Sarampo/patologia , Sarampo/prevenção & controle , Vacina contra Sarampo/administração & dosagem , Fatores de Risco , Vacinação/estatística & dados numéricos
2.
AJNR Am J Neuroradiol ; 38(11): 2199-2202, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28705823

RESUMO

Children who present with acute transient focal neurologic symptoms raise concern for stroke or transient ischemic attack. We present a series of 16 children who presented with transient focal neurologic symptoms that raised concern for acute stroke but who had no evidence of infarction and had unilateral, potentially reversible imaging features on vascular and perfusion-sensitive brain MR imaging. Patients were examined with routine brain MR imaging, MRA, perfusion-sensitive sequences, and DWI. Fourteen (88%) children had lateralized MRA evidence of arterial tree pruning without occlusion, all had negative DWI findings, and all showed evidence of hemispheric hypoperfusion by susceptibility-weighted imaging or arterial spin-labeling perfusion imaging at presentation. These findings normalized following resolution of symptoms in all children who had follow-up imaging (6/16, 38%). The use of MR imaging with perfusion-sensitive sequences, DWI, and MRA can help to rapidly distinguish children with conditions mimicking stroke from those with acute stroke.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Neuroimagem/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Idoso , Circulação Cerebrovascular , Criança , Feminino , Humanos , Ataque Isquêmico Transitório/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Imagem de Perfusão
3.
Neurology ; 75(23): 2110-6, 2010 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-21135385

RESUMO

BACKGROUND: Understanding the maturation and organization of cognitive function in the brain is a central objective of both child neurology and developmental cognitive neuroscience. This study focuses on episodic memory encoding of verbal information by children, a cognitive domain not previously studied using fMRI. METHODS: Children from 7 to 19 years of age were scanned at 1.5-T field strength using event-related fMRI while performing a novel verbal memory encoding paradigm in which words were incidentally encoded. A subsequent memory analysis was performed. SPM2 was utilized for whole brain and region-of-interest analyses of data. Both whole-sample intragroup analyses and intergroup analyses of the sample divided into 2 subgroups by age were conducted. RESULTS: Importantly, behavioral memory performance was equal across the age range of children studied. Encoding-related activation in the left hippocampus and bilateral basal ganglia declined as age increased. In addition, while robust blood oxygen level-dependent signal was found in left prefrontal cortex with task performance, no encoding-related age-modulated prefrontal activation was observed in either hemisphere. CONCLUSION: These data are consistent with a developmental pattern of verbal memory encoding function in which left hippocampal and bilateral basal ganglionic activations are more robust earlier in childhood but then decline with age. No encoding-related activation was found in prefrontal cortex which may relate to this region's recognized delay in biologic maturation in humans. These data represent the first fMRI demonstration of verbal encoding function in children and are relevant developmentally and clinically.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/crescimento & desenvolvimento , Desenvolvimento Infantil/fisiologia , Imageamento por Ressonância Magnética/métodos , Rememoração Mental/fisiologia , Aprendizagem Verbal/fisiologia , Adolescente , Fatores Etários , Mapeamento Encefálico , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Modelos Lineares , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Psicolinguística , Adulto Jovem
4.
Neuroimage ; 35(1): 308-25, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17239623

RESUMO

The Magn. Reson. Imaging (MRI) study of normal brain development currently conducted by the Brain Development Cooperative Group represents the most extensive MRI study of brain and behavioral development from birth through young adulthood ever conducted. This multi-center project, sponsored by four Institutes of the National Institutes of Health, uses a combined longitudinal and cross-sectional design to characterize normal, healthy brain and behavioral development. Children, ages newborn through 18-plus years of age, receive comprehensive behavioral, neurological and multimodal MRI evaluations via Objective-2 (birth through 4-years 5-months of age) and Objective-1 (4-years 6-months through 18 years of age and older). This report presents methods (e.g., neurobehavioral assessment, brain scan) and representative preliminary results (e.g., growth, behavior, brain development) for children from newborn through 4-years 5-months of age. To date, 75 participants from birth through 4-years 5-months have been successfully brain scanned during natural sleep (i.e., without sedation); most with multiple longitudinal scans (i.e., 45 children completing at least three scans, 22 completing four or more scans). Results from this younger age range will increase our knowledge and understanding of healthy brain and neurobehavioral development throughout an important, dynamic, and rapid growth period within the human life span; determine developmental associations among measures of brain, other physical characteristics, and behavior; and facilitate the development of automated, quantitative MR image analyses for neonates, infants and young children. The correlated brain MRI and neurobehavioral database will be released for use by the research and clinical communities at a future date.


Assuntos
Encéfalo/crescimento & desenvolvimento , Imageamento por Ressonância Magnética , Envelhecimento/fisiologia , Encéfalo/anatomia & histologia , Química Encefálica , Criança , Comportamento Infantil , Pré-Escolar , Estudos de Coortes , Estudos Transversais , Bases de Dados Factuais , Imagem de Difusão por Ressonância Magnética , Etnicidade , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Lactente , Comportamento do Lactente , Recém-Nascido , Estudos Longitudinais , Espectroscopia de Ressonância Magnética , Masculino , National Institutes of Health (U.S.) , Testes Neuropsicológicos , Controle de Qualidade , Valores de Referência , Reprodutibilidade dos Testes , Estados Unidos
5.
J Inherit Metab Dis ; 29(1): 214-9, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16601897

RESUMO

We report two unrelated boys with the X-linked creatine transporter defect (CRTR) and clinical features more severe than those previously described with this disorder. These two boys presented at ages 12 and 30 months with severe mental retardation, absent speech development, hypotonia, myopathy and extra-pyramidal movement disorder. One boy has seizures and some dysmorphic features; he also has evidence of an oxidative phosphorylation defect. They both had classical absence of creatine peak on brain magnetic resonance spectroscopy (MRS). In one, however, this critical finding was overlooked in the initial interpretation and was discovered upon subsequent review of the MRS. Molecular studies showed large genomic deletions of a large part of the 3' end of the complete open reading frame of the SLC6A8 gene. This report emphasizes the importance of MRS in evaluating neurological symptoms, broadens the phenotypic spectrum of CRTR and adds knowledge about the pathogenesis of creatine depletion in the brain and retina.


Assuntos
Cromossomos Humanos X , Proteínas de Membrana Transportadoras/deficiência , Proteínas de Membrana Transportadoras/genética , Erros Inatos do Metabolismo/genética , Pré-Escolar , Olho/patologia , Deleção de Genes , Humanos , Lactente , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Espectroscopia de Ressonância Magnética , Masculino , Erros Inatos do Metabolismo/diagnóstico , Proteínas do Tecido Nervoso/genética , Oxigênio/metabolismo , Fenótipo , Fosforilação , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/genética
6.
Magn Reson Med ; 51(6): 1287-91, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15170852

RESUMO

The neonatal brain possesses higher water content, lower macromolecular concentration, and reduced synaptic density than is found in the brain of a 1-year-old child. Changes in MRI characteristics of brain such as relaxation times accompany rapid changes in brain during early postnatal development. It was hypothesized that T(*)(2) values found in newborns would be significantly higher than those found in 9-month-old children and adults as measured at 1.5 T. Spoiled gradient echo measurements of T(*)(2) within the brains of newborns, 9-month-olds, and adults confirmed this hypothesis. The results have implications with regard to functional MRI studies in newborns since, in general, BOLD signal optimization is achieved when echo times TE are set equal to the T(*)(2) values of the tissue of interest. Since significantly longer T(*)(2) values are found in newborns, it is suggested that the TE values employed for fMRI studies of newborns should be increased to maximize BOLD signal intensity changes and improve the overall reliability of fMRI results in newborns.


Assuntos
Encéfalo/anatomia & histologia , Adulto , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
7.
Neurology ; 58(12): 1726-38, 2002 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-12084869

RESUMO

OBJECTIVE: The authors reviewed available evidence on neonatal neuroimaging strategies for evaluating both very low birth weight preterm infants and encephalopathic term neonates. IMAGING FOR THE PRETERM NEONATE: Routine screening cranial ultrasonography (US) should be performed on all infants of <30 weeks' gestation once between 7 and 14 days of age and should be optimally repeated between 36 and 40 weeks' postmenstrual age. This strategy detects lesions such as intraventricular hemorrhage, which influences clinical care, and those such as periventricular leukomalacia and low-pressure ventriculomegaly, which provide information about long-term neurodevelopmental outcome. There is insufficient evidence for routine MRI of all very low birth weight preterm infants with abnormal results of cranial US. IMAGING FOR THE TERM INFANT: Noncontrast CT should be performed to detect hemorrhagic lesions in the encephalopathic term infant with a history of birth trauma, low hematocrit, or coagulopathy. If CT findings are inconclusive, MRI should be performed between days 2 and 8 to assess the location and extent of injury. The pattern of injury identified with conventional MRI may provide diagnostic and prognostic information for term infants with evidence of encephalopathy. In particular, basal ganglia and thalamic lesions detected by conventional MRI are associated with poor neurodevelopmental outcome. Diffusion-weighted imaging may allow earlier detection of these cerebral injuries. RECOMMENDATIONS: US plays an established role in the management of preterm neonates of <30 weeks' gestation. US also provides valuable prognostic information when the infant reaches 40 weeks' postmenstrual age. For encephalopathic term infants, early CT should be used to exclude hemorrhage; MRI should be performed later in the first postnatal week to establish the pattern of injury and predict neurologic outcome.


Assuntos
Lesões Encefálicas/diagnóstico , Recém-Nascido , Triagem Neonatal/normas , Academias e Institutos/normas , Lesões Encefálicas/diagnóstico por imagem , Humanos , Recém-Nascido Prematuro , Imageamento por Ressonância Magnética/métodos , Triagem Neonatal/métodos , Neurologia/normas , Radiografia , Ultrassonografia
8.
Magn Reson Imaging ; 19(5): 659-68, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11672624

RESUMO

The decay of brain water signal with b-factor in adult and newborn brains has been measured over an extended b-factor range. Measurements of the apparent diffusion coefficient (ADC) decay curves were made at 16 b-factors from 100 to 5000 s/mm(2) along three orthogonal directions using a line scan diffusion imaging (LSDI) sequence to acquire data from 0.09 ml voxels in a mid-brain axial slice. Regions-of-interest (ROIs) in cortical gray (CG) and white matter in the internal capsule (IC) were selected for ADC decay curve analyses using a biexponential fitting model over this extended b-factor range. Measures of the fast and slow ADC component amplitudes and the traces of the fast and slow diffusion coefficients were obtained from CG and IC ROIs in both adults and newborns. The ADC decay curves from the newborn brain regions were found to have a significantly higher fraction of the fast diffusion ADC component than corresponding regions in the adult brain. The results demonstrate that post-natal brain development has a profound affect on the biexponential parameters which characterize the decay of water signal over an extended b-factor range in both gray and white matter.


Assuntos
Encefalopatias/diagnóstico , Edema Encefálico/diagnóstico , Encéfalo/patologia , Imageamento por Ressonância Magnética , Equilíbrio Hidroeletrolítico/fisiologia , Adulto , Córtex Cerebral/patologia , Difusão , Feminino , Humanos , Aumento da Imagem , Recém-Nascido , Cápsula Interna/patologia , Masculino , Imagens de Fantasmas , Valores de Referência , Sensibilidade e Especificidade
9.
Circ Res ; 89(4): 323-8, 2001 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-11509448

RESUMO

Inhibition of proliferative neointima formed by vascular smooth muscle cells is a potential target in preventing angioplasty-induced restenosis. We have created a potent antiproliferative by fusing the active regions of the p27 and p16 cell cycle inhibitors. Intravascular delivery of a replication-deficient adenoviral vector (AV) encoding this p27-p16 fusion protein, named W9, inhibited balloon injury-induced neointimal hyperplasia in rabbit carotid arteries. In a therapeutically more relevant model, AV-W9 was delivered to balloon-injured porcine coronary arteries in vivo using an infusion catheter. Of the three coronary arteries, two were injured with a 15-mm balloon catheter and either were left untreated or were treated with 10(12) viral particles of either AV-W9 or a control null virus. AV-W9 treatment significantly inhibited neointimal hyperplasia in this porcine arterial balloon injury model compared with untreated or control virus-treated vessels. The average intimal area of the AV-W9-treated group 10 days after balloon injury and treatment was 0.42+/-0.36 mm(2), whereas the AV-null group demonstrated an intimal area of 0.70+/-0.52 mm(2). At day 10 the average intimal thickness of the AV-W9-treated vessels was 9.1 microm (n=5, x 20 magnification) compared with 21.2 microm (n=5, x 20 magnification) in control virus-treated vessels. This trend was also observed at 28 days after balloon injury and gene transfer during which AV-W9-treated vessels demonstrated an average intimal thickness of 4.7 microm (n=8, x 20 magnification) compared with 13.3 microm (n=3, x 20 magnification) in control virus-treated vessels and 7.3 microm (n=5, x 20 magnification) in the sham-treated vessels. The AV-W9 treatment was safe and well tolerated. These data suggest that AV-W9 gene therapy may be useful in preventing angioplasty-induced intimal hyperplasia in the coronary artery.


Assuntos
Angioplastia Coronária com Balão/efeitos adversos , Proteínas de Ciclo Celular/genética , Doença das Coronárias/prevenção & controle , Inibidor p16 de Quinase Dependente de Ciclina/genética , Terapia Genética/métodos , Hiperplasia/prevenção & controle , Proteínas Supressoras de Tumor , Adenoviridae/genética , Animais , Cateterismo Cardíaco , Células Cultivadas , Doença das Coronárias/etiologia , Doença das Coronárias/patologia , Inibidor de Quinase Dependente de Ciclina p27 , Quinases Ciclina-Dependentes/antagonistas & inibidores , Modelos Animais de Doenças , Feminino , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Humanos , Infusões Intra-Arteriais , Masculino , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Coelhos , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Suínos , Transdução Genética/métodos , Resultado do Tratamento , Túnica Íntima/patologia
10.
Mol Ther ; 2(2): 161-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10947944

RESUMO

We describe here that DE1-adenovirus vectors (AV) expressing a p27-p16 fusion molecule, termed W9, induce tumor cell apoptosis when overexpressed in a wide range of tumor cell types. However, in primary human cells derived from a variety of normal tissues, AV-W9 induced minimal apoptosis. In tumor cells AV-W9 demonstrated 5- to 50-fold greater tumoricidal activity than either of the parental molecules p16 and p27. In these studies, AV-W9 elicited apoptosis independent of the p53 and Rb status of the tumor cells. In several murine tumor models AV-W9 demonstrated p53-independent antitumor activity. It completely prevented tumor formation in two ex vivo models, whereas the parental molecules resulted in partial protection. Furthermore, AV-W9 induced tumor regression or suppressed tumor growth when introduced intratumorally into preestablished tumors in mice. This effect may be mediated through tumor cell apoptosis or antiangiogenic activity of AV-W9. Thus, this novel chimeric molecule is more potent and capable of killing a broader spectrum of tumors than the parental p16 and p27 molecules independent of the tumor cell p53 and phenotype and represents a powerful new therapeutic agent for cancer gene therapy.


Assuntos
Adenoviridae/genética , Proteínas de Ciclo Celular , Inibidor p16 de Quinase Dependente de Ciclina/genética , Genes Supressores de Tumor , Genes p53 , Terapia Genética , Proteínas Associadas aos Microtúbulos/genética , Neoplasias/terapia , Proteínas Supressoras de Tumor , Animais , Anexina A5/metabolismo , Aorta/metabolismo , Apoptose , Linhagem Celular , Separação Celular , Inibidor de Quinase Dependente de Ciclina p27 , Citometria de Fluxo , Vetores Genéticos , Humanos , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Proteínas Recombinantes de Fusão/genética , Proteína do Retinoblastoma/metabolismo , Fatores de Tempo , Células Tumorais Cultivadas
11.
J Neurosci ; 20(15): 5647-53, 2000 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10908602

RESUMO

The precise mechanisms by which beneficial responses to acute stress are transformed into long-term pathological effects of chronic stress are largely unknown. Western blot analyses revealed that members of the AP1 transcription factor family are differentially regulated by single and repeated stress in the rat adrenal medulla, suggesting distinct roles in establishing stress-induced patterns of gene expression in this tissue. The induction of c-fos was transient, whereas marked elevation of long-lasting Fos-related antigens, including Fra2, was observed after repeated immobilization. We investigated DNA protein interactions at the AP1-like promoter elements of two stress-responsive genes, tyrosine hydroxylase and dopamine beta-hydroxylase. Increased DNA-binding activity was displayed in adrenomedullary extract from repeatedly stressed rats, which was predominantly composed of c-Jun- and Fra2-containing dimers. The induction of Fra2 and increased AP1-like binding activity was reflected in sustained transcriptional activation of tyrosine hydroxylase and dopamine beta-hydroxylase genes after repeated episodes of stress. The functional link between Fra2 and regulation of tyrosine hydroxylase and dopamine beta-hydroxylase transcription was confirmed in PC12 cells coexpressing this factor and the corresponding promoter-reporter gene constructs. These studies emphasize the potential importance of stress-evoked increases in the expression of the Fra2 gene for in vivo adaptations of the adrenal catecholamine producing system.


Assuntos
Medula Suprarrenal/fisiologia , Proteínas de Ligação a DNA/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Estresse Fisiológico/fisiopatologia , Fatores de Transcrição/metabolismo , Ativação Transcricional/fisiologia , Animais , Proteínas de Ligação a DNA/genética , Dopamina beta-Hidroxilase/genética , Dopamina beta-Hidroxilase/metabolismo , Antígeno 2 Relacionado a Fos , Regulação Enzimológica da Expressão Gênica/fisiologia , Masculino , Neurônios/citologia , Neurônios/enzimologia , Células PC12 , Regiões Promotoras Genéticas/fisiologia , Ligação Proteica/fisiologia , Proteínas Proto-Oncogênicas c-fos/genética , Ratos , Ratos Sprague-Dawley , Restrição Física , Organismos Livres de Patógenos Específicos , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Fatores de Transcrição/genética , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-10899799

RESUMO

Cognitive and motor development in children remain fascinating processes that are uniquely human. Progress has been made in recent years in elucidating the prenatal process of human brain development. In addition, much information exists regarding the behavioral aspects of postnatal human development. However, little is known about the relationship between anatomic postnatal central nervous system development and the accretion of functional milestones observed in children from the neonatal period through adolescence. Recently, powerful qualitative and quantitative magnetic resonance techniques have been developed that will permit detailed inquiry into the connection between the developing brain and the developing mind. In this review, first, the steps of prenatal and postnatal brain development are reviewed briefly. Subsequently, recent magnetic resonance imaging data related to human brain development during the fetal, neonatal, and later childhood periods are presented. Finally, functional magnetic resonance imaging (fMRI) is discussed. Specific examples of its usefulness are provided. Magnetic resonance imaging techniques such as quantitative MRI, volumetric MRI, diffusion tensor imaging, and functional magnetic resonance imaging (fMRI) when combined with neurologic and neuropsychologic evaluation, will provide new insights into the cognitive development of children. MRDD Research Reviews 6:68-80, 2000.


Assuntos
Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Desenvolvimento Infantil , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Encéfalo/anatomia & histologia , Feto/anatomia & histologia , Humanos , Recém-Nascido , Bainha de Mielina/fisiologia
13.
AJNR Am J Neuroradiol ; 20(9): 1658-70, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10543637

RESUMO

BACKGROUND AND PURPOSE: MR diffusion-weighted imaging provides early demonstration of neonatal brain infarction. The evolution and limitations of diffusion-weighted imaging findings in newborns, however, have not been evaluated. Using line-scan diffusion imaging (LSDI), we investigated perinatal ischemic brain injury. METHODS: Nineteen term newborns (age, 9 hours to 8 days; mean age, 2.6 days) with perinatal brain ischemia were evaluated using LSDI (1520/62.5/1 [TR/TE/excitations]) (b maximum = 750 s/mm2) and T1- and T2-weighted spin-echo (conventional) MR imaging. Follow-up examinations were performed in seven patients and autopsy in one. Apparent diffusion coefficients (ADCs) were measured in deep gray matter, white matter, the cortex, and focal lesions. RESULTS: Based on conventional MR imaging or pathologic findings, patients were divided into two groups. Group 1 (n = 12) had symmetric/diffuse injury consistent with global hypoperfusion. Group 2 (n = 7) had focal/multifocal injury suggesting cerebrovascular occlusion. ADCs were abnormal at initial examination in 10 newborns in group 1 and in all newborns in group 2. The results of LSDI were abnormal before conventional MR imaging was performed in three newborns in group 1. ADCs were maximally decreased between days 1 and 3 in deep gray matter, perirolandic white matter, and focal lesions. Delayed decreases in ADCs were observed in subcortical white matter from days 4 through 10 in three patients in group 1. CONCLUSION: After global hypoperfusion, LSDI showed deep gray matter and perirolandic white matter lesions before conventional MR imaging. LSDI may underestimate the extent of injury, however, possibly because of variations in the compartmentalization of edema, selective vulnerability, and delayed cell death. Differences in LSDI of symmetric/diffuse and focal/multifocal lesions may reflect differences in pathophysiology or timing of the injury. These findings may have implications for acute interventions.


Assuntos
Asfixia Neonatal/diagnóstico , Dano Encefálico Crônico/diagnóstico , Infarto Cerebral/diagnóstico , Aumento da Imagem , Imageamento por Ressonância Magnética , Encéfalo/patologia , Difusão , Dominância Cerebral/fisiologia , Feminino , Humanos , Recém-Nascido , Masculino
14.
Genome ; 42(1): 41-7, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10208000

RESUMO

Primers based on a conserved nucleotide binding site (NBS) found in several cloned plant disease resistance genes were used to amplify DNA fragments from the genome of common bean (Phaseolus vulgaris). Cloning and sequence analysis of these fragments uncovered eight unique classes of disease-resistance related sequences. All eight classes contained the conserved kinase 2 motif, and five classes contained the kinase 3a motif. Gene expression was noted for five of the eight classes of sequences. A clone from the SB3 class mapped 17.8 cM from the Ur-6 gene that confers resistance to several races of the bean rust pathogen Uromyces appendiculatus. Linkage mapping identified microclusters of disease-resistance related sequence in common bean, and sequences mapped to four linkage groups in one population. Comparison with similar sequences from soybean (Glycine max) revealed that any one class of common bean disease-resistance related sequences was more identical to a soybean NBS-containing sequence than to the sequence of another common bean class.


Assuntos
Fabaceae/genética , Imunidade Inata/genética , Plantas Medicinais , Sequência de Aminoácidos , Clonagem Molecular , Cruzamentos Genéticos , Primers do DNA , Genes de Plantas , Ligação Genética , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
15.
Am J Surg Pathol ; 22(9): 1141-7, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9737248

RESUMO

A 14-year-old girl with the mitochondrial neurogastrointestinal encephalopathy syndrome had an 8-year history of intestinal pseudoobstruction with abdominal pain, persistent vomiting, gastric and duodenal dilatation, and duodenal diverticulosis. The child appeared chronically malnourished and had severe growth failure. Multisystem involvement was evident with the presence of ptosis, external ophthalmoplegia, muscle wasting, peripheral neuropathy, and diffuse white matter disease seen on magnetic resonance imaging. Lactic acidosis and increased cerebrospinal fluid protein were observed. Mitochondrial enzyme analysis of fresh-frozen skeletal muscle revealed a respiratory chain defect. Molecular genetic studies showed multiple mitochondrial DNA deletions. Pathologic findings in the intestine included atrophy of the external layer of the muscularis propria and an increased number of abnormal-appearing mitochondria in ganglion and smooth-muscle cells. Microvesicular steatosis was observed in liver, skeletal, and gastrointestinal smooth muscle, and Schwann cells of peripheral nerve. Brightly eosinophilic inclusions in the cytoplasm of gastrointestinal ganglion cells were visible by light microscopy, which were confirmed to be megamitochondria by ultrastructural studies. This is the first report of abnormal mitochondria observed in intestinal ganglion and smooth-muscle cells in this syndrome.


Assuntos
Pseudo-Obstrução Intestinal/patologia , Miopatias Mitocondriais/patologia , Reto/patologia , Adolescente , Biópsia/métodos , DNA Mitocondrial/análise , Feminino , Humanos , Microscopia Eletrônica , Músculos/patologia , Reto/inervação
16.
Am J Med Genet ; 78(2): 173-5, 1998 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-9674911

RESUMO

The gene for the gastrin-releasing peptide receptor (GRPR) has been mapped to a candidate region for Rett syndrome (RTT) on the short arm of the X chromosome. The recent report of a translocation that disrupted the gene in an individual with mental retardation and autistic behavior prompted us to examine GRPR as a possible locus for RTT. Genomic polymerase chain reaction amplification of exons followed by single-strand conformation analysis screening in 25 unrelated RTT-affected individuals and by direct sequencing in 12 others has failed to detect any mutation. No gross structural rearrangements were found by Southern analysis of DNA from six unrelated RTT-affected individuals. A high-frequency biallelic polymorphism caused by two single nucleotide substitutions in exon 2 was discovered. The allele frequencies were identical in the RTT population as compared to 100 normal control X chromosomes. This polymorphism will enable future evaluation of the GRPR locus as a candidate for other X-linked mental retardation or neurobehavioral syndromes.


Assuntos
Receptores da Bombesina/genética , Síndrome de Rett/genética , Cromossomo X , Southern Blotting , Mapeamento Cromossômico , Éxons , Polimorfismo Genético
17.
Clin Perinatol ; 24(3): 607-25, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9394863

RESUMO

Hypoxic-ischemic cerebral injury in the full-term infant results in a variety of neurologic manifestations. The pathogenetic events resulting in this central nervous system injury may occur throughout the prenatal period. Several clinical patterns of signs and symptoms of hypoxic-ischemic cerebral injury have been identified in the term infant. Further, characteristic neuroradiologic patterns of this injury can be discerned. Information derived from the term infant's clinical course and neuroimaging data convey useful neurodevelopmental prognostic information. Several potential and promising therapeutic agents exist may attenuate the sequelae of hypoxic-ischemic cerebral injury to the term infant.


Assuntos
Encefalopatias/etiologia , Isquemia Encefálica/complicações , Hipóxia Encefálica/complicações , Asfixia Neonatal/complicações , Encefalopatias/diagnóstico , Encefalopatias/patologia , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/patologia , Circulação Cerebrovascular , Diagnóstico por Imagem , Hipóxia Fetal/complicações , Humanos , Hipóxia Encefálica/diagnóstico , Hipóxia Encefálica/patologia , Recém-Nascido , Imageamento por Ressonância Magnética
18.
Brain Res Mol Brain Res ; 48(2): 251-8, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9332722

RESUMO

GTP cyclohydrolase I (GTPCH) is the rate-limiting enzyme in the formation of tetrahydrobiopterin, the cofactor for catecholamine, indolamine and nitric oxide biosynthesis. The effect of glucocorticoids on GTPCH gene expression was examined by direct infusion of cortisol to rats and by incubation of PC12 cells with glucocorticoids. Northern blot analysis revealed that infusion of cortisol for 1 or 7 days elevated levels of the 3.6 kb GTPCH mRNA species in rat adrenal medulla, while the 1.2 kb mRNA species were only increased by 1 day cortisol. Cortisol administration to hypophysectomized animals elicited a 4-5-fold elevation in both forms of GTPCH mRNA. These results indicate that glucocorticoids may be directly involved in the regulation of adrenomedullary GTPCH mRNA levels by physiological stress. Incubation of PC12 cells with plasma from immobilized, but not control, animals increased the level of the 3.6 kb mRNA. Treatment of PC12 cells with dexamethasone for 12-48 h elicited a 4-6-fold elevation in both GTPCH mRNAs. Using the nuclear run-on assay, increased transcription of the GTPCH gene was observed in the rat adrenal medulla with immobilization stress, or in PC12 cells treated with dexamethasone. This is the first report that glucocorticoids can alter GTPCH expression.


Assuntos
GTP Cicloidrolase/genética , Glucocorticoides/farmacologia , RNA Mensageiro/metabolismo , Medula Suprarrenal/efeitos dos fármacos , Medula Suprarrenal/metabolismo , Animais , Dexametasona/farmacologia , Hidrocortisona/farmacologia , Masculino , Células PC12 , Ratos , Ratos Sprague-Dawley , Restrição Física
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