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1.
Arch Dis Child Fetal Neonatal Ed ; 88(5): F371-4, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12937039

RESUMO

OBJECTIVES: To define the incidence of congenital cytomegalovirus (CMV) infection in a defined population in Israel as diagnosed by urine polymerase chain reaction (PCR), and to assess the utility of this method for screening for congenital CMV infection. DESIGN: A convenient sample of urine specimens from asymptomatic newborns were subjected to CMV PCR. Positive results were validated by urine tube culture and by determination of serum CMV IgM antibodies. Maternal CMV IgG was determined in a representative sample of mothers. Newborns with positive urine specimens underwent full clinical evaluation. Epidemiological characteristics of the mothers were extracted from the medical records. SETTINGS: Two medical centres in Israel with different population characteristics. PATIENTS: A total of 2000 newborns (1000 in each medical centre). MAIN OUTCOME MEASURE: Presence of CMV DNA in the urine. RESULTS: Despite significant epidemiological differences between the populations in the two hospitals, the CMV seroprevalence was similar, 80.5% and 85%. Fourteen of the 2000 newborns screened (0.7%) were PCR positive. Urine culture was positive in nine of 10 specimens; IgM was positive in only two of 13 newborns with positive PCR. Eleven newborns underwent full or partial evaluation, and only one (9%) was symptomatic. CONCLUSIONS: The incidence of congenital CMV infection in the study population was 0.7%; over 90% were asymptomatic. Urinary CMV PCR is a reliable, rapid, and convenient method, and thus may serve as a screening tool for the detection of congenital CMV infection.


Assuntos
Infecções por Citomegalovirus/congênito , Reação em Cadeia da Polimerase/normas , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/epidemiologia , DNA Viral/urina , Feminino , Sangue Fetal/virologia , Humanos , Imunoglobulina G/análise , Incidência , Recém-Nascido , Israel/epidemiologia , Masculino , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , Reação em Cadeia da Polimerase/métodos , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Saúde da População Rural , Sensibilidade e Especificidade , Saúde da População Urbana
2.
Exp Gerontol ; 33(5): 467-76, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9762524

RESUMO

To understand the mechanisms of improvement of cold-induced heat production in aged mice following exercise training, the relative contributions of shivering and nonshivering thermogenesis to cold-induced metabolic responses were assessed in adult and aged C57BL/6J male mice, which inhabited sedentarily at room temperature, or were subjected either to a regimen of moderate intensity exercise training at 6 degrees C, or to sedentary repeated exposures to the same temperature. The main findings were that (1) aged mice had greater cold-induced nonshivering thermogenesis, but lower shivering than adult mice; (2) exercise training in a cold environment enhanced cold-induced nonshivering thermogenesis in adult mice, but suppressed it in aged animals; (3) exercise training in a cold environment increased shivering thermogenesis in both age groups, but this increase was much greater in aged mice; (4) the increase of cold-induced shivering thermogenesis was mainly responsible for increased cold tolerance in aged mice after exercise training in a cold environment.


Assuntos
Envelhecimento/fisiologia , Regulação da Temperatura Corporal/fisiologia , Temperatura Baixa , Condicionamento Físico Animal/fisiologia , Estremecimento/fisiologia , Análise de Variância , Anestésicos/farmacologia , Animais , Temperatura Corporal/efeitos dos fármacos , Temperatura Corporal/fisiologia , Peso Corporal/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuromusculares não Despolarizantes/farmacologia , Consumo de Oxigênio/efeitos dos fármacos , Consumo de Oxigênio/fisiologia , Uretana/farmacologia , Brometo de Vecurônio/farmacologia
3.
Neurosci Behav Physiol ; 27(6): 653-62, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9406216

RESUMO

This article presents the results of three series of experiments on cats, dogs, and lower primates, performed to investigate the structural, neurophysiological, and mediator mechanisms of the corticostriatal systems involved in the organization of behavior. Morphological studies of corticostriatal connections showed that along with the diffuse distribution of afferent terminals within the striatum, there were also elements of topical organization defined by anteroposterior and mediolateral gradients. Neurophysiological experiments on dogs and lower primates were used to study the spike activity of the prefrontal region of the cortex and the head of the caudate nucleus during training to conditioned first- and second-order reflexes and during the solution of complex problems involving delayed spatial selection. Studies demonstrated that while in dogs, most of the neurons recorded showed a transition to responses to the conditioned signal at a particular stage of carrying out a conditioned response, in monkeys all cells recorded showed specific responses at different periods of solving the task at all stages of the study. Neuropharmacological experiments on dogs showed that agents blocking glutamine receptors in the caudate nucleus had more pronounced effects at the phase of developing conditioned movement reflexes. Administration of these agents during the reflex reinforcement phase affected only the differentiation of inhibition. These results lead to the conclusion that the prefrontal area of the cortex and, to some extent, the caudate nuclei, act on incoming information specifying the current dominant need and the states of the external and internal environments, to carry out programmed actions and assess the results of these actions.


Assuntos
Comportamento Animal/fisiologia , Córtex Cerebral/fisiologia , Corpo Estriado/fisiologia , Potenciais de Ação , Animais , Gatos , Núcleo Caudado/fisiologia , Condicionamento Clássico/fisiologia , Cães , Antagonistas de Aminoácidos Excitatórios/farmacologia , Macaca mulatta , Macaca nemestrina , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia
4.
Exp Gerontol ; 32(3): 325-32, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9193900

RESUMO

Previous studies have shown that adult mice increase cold-induced heat production as a result of repeated exposures to cold, but that aged mice do not. The objective of the present study was to investigate changes in heat loss during repeated cold exposures in adult and aged C57BL/6J mice. Mice were partially restrained for three hours at 6 degrees C, three times at one-week intervals. Dry heat loss was inferred from measurements of differential temperature between the incoming and outgoing air in the experimental chamber. During the first cold exposure, aged mice showed less heat loss (both total and adjusted for body temperature) than adult animals, suggesting greater peripheral vasoconstriction in aged mice. With repeated cold exposures, both age groups showed increased heat loss, but the aged mice showed greater increase of heat loss, so that by the third cold stress test, no significant differences in heat loss between adult and aged mice were observed. The increase of heat loss after repeated cold exposures in aged mice might reflect a lesser peripheral vasoconstriction, serving to reduce the possibility of tissue necrosis in the cold.


Assuntos
Aclimatação , Envelhecimento/fisiologia , Regulação da Temperatura Corporal/fisiologia , Temperatura Baixa , Análise de Variância , Animais , Superfície Corporal , Modelos Lineares , Masculino , Camundongos , Camundongos Endogâmicos C57BL
5.
Neurosci Behav Physiol ; 27(3): 288-96, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9194069

RESUMO

Experimental data are discussed within the framework of the fundamental areas of studies of the neurophysiological mechanisms of behavior. The first of these is the study of the activity of individual neurons, which is characterized by plastic rearrangements based on synaptic, molecular (neurochemical), and submolecular (genetic) processes. The second area is the study of the activity of neuron systems, which unite the cells of different microgroups, and of systems including neural elements of different brain structures. Data on plastic rearrangements of neuronal activity in different structures during different types of behavior lead to the conclusion that the brain has special systems of relationships which characterize the interactions of blocks of neurons, in which the plasticity of a single neuron can maintain the integration processes of the whole system. Our own data, along with results of Russian and foreign physiological and clinical investigations, suggest that neurons unite into different functional blocks at different phases of conditioned reflex behavior, thus determining the dominance status of different centers and the vector of a purposive behavioral act in a given situation at a given time. Possible directions for further basic studies of the interactions between innate and phylogenetically acquired functionally specific neuron units are discussed on the basis of hypotheses which have been advanced to explain the neurophysiological organizational mechanisms of higher brain functions.


Assuntos
Comportamento/fisiologia , Córtex Cerebral/fisiologia , Fenômenos Fisiológicos do Sistema Nervoso , Animais , Comportamento Animal/fisiologia , Humanos , Neurônios/fisiologia
6.
Exp Gerontol ; 32(6): 695-705, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9785095

RESUMO

We studied the effect of exercise training in cold environment (six weeks of daily, one-hour runs on a treadmill at ambient temperature of 6 +/- 1 degrees C at 60-65% of VO2max) on cold-induced metabolic heat production, heat loss, and cold tolerance in adult and aged C57BL/6J male mice. In adult mice, exercise training in cold environment resulted in greater cold-induced heat production and cold tolerance without changes in heat loss, similar to the effects of daily cold exposure without exercise. In aged mice, daily cold exposures did not affect cold tolerance and cold-induced heat production, but exercise training in the cold resulted in greater cold-induced heat production and cold tolerance. Heat loss in aged mice increased similarly after both repeated cold exposures and exercise training in the cold. Therefore, mechanisms of effect of exercise training on cold tolerance are different in adult and aged animals. Exercise training in cold environment does not affect cold-induced heat production and cold tolerance in adult mice, but improves them in aged animals.


Assuntos
Envelhecimento/fisiologia , Regulação da Temperatura Corporal/fisiologia , Temperatura Baixa , Condicionamento Físico Animal , Aclimatação/fisiologia , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL
7.
Exp Gerontol ; 31(5): 597-604, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9415115

RESUMO

Metabolic heat production (MHP), colonic temperature (Tco), and nonevaporative (dry) heat loss were measured in ADULT and AGED C57BL/6J male mice during cold exposure. Dry heat loss was assessed as a differential temperature (Td) between incoming and outgoing air through the chamber for indirect calorimetry. The average Td during cold exposure normalized to surface area for ADULT mice was significantly higher than that for the AGED animals (0.0618 +/- 0.0003 degree C/cm2 and 0.0553 +/- 0.0005 degree C/cm2, respectively). Linear regression analysis showed that at the same Tco AGED mice showed lower values of Td normalized to surface area, indicating that at the same body temperature they were losing less heat than ADULT animals. It was concluded that age-related decline in cold tolerance in mice is not due to a lack of ability to reduce heat loss during cold exposure. On the contrary, AGED animals had lower heat loss in comparison with ADULT. We suggest that augmentation of heat conservation mechanisms is an adaptive response to diminishing cold-induced heat production.


Assuntos
Envelhecimento/fisiologia , Regulação da Temperatura Corporal , Animais , Temperatura Baixa , Masculino , Camundongos , Camundongos Endogâmicos C57BL
8.
Fiziol Zh Im I M Sechenova ; 81(12): 1-12, 1995 Dec.
Artigo em Russo | MEDLINE | ID: mdl-8754022

RESUMO

Experiments in dogs, cats and monkeys revealed that, along with the diffuse principle of afferent terminal arrangement within the striatum, there exist some features of terminal organisation by the anterior-posterior and medio-lateral gradients. The data obtained suggest that the prefrontal cortex and the caudate nucleus head maintain programming of intentions and the evaluation of performed actions.


Assuntos
Comportamento Animal/fisiologia , Corpo Estriado/fisiologia , Córtex Pré-Frontal/fisiologia , Ácido 2-Aminoadípico/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Mapeamento Encefálico , Gatos , Condicionamento Clássico/efeitos dos fármacos , Condicionamento Clássico/fisiologia , Corpo Estriado/efeitos dos fármacos , Cães , Antagonistas de Aminoácidos Excitatórios/farmacologia , Glutamatos/farmacologia , Macaca mulatta , Macaca nemestrina , Microeletrodos , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Córtex Pré-Frontal/efeitos dos fármacos , Tempo de Reação/efeitos dos fármacos , Tempo de Reação/fisiologia
9.
Fiziol Zh Im I M Sechenova ; 81(8): 110-20, 1995 Aug.
Artigo em Russo | MEDLINE | ID: mdl-8775444

RESUMO

Specific intersystem relationships seem to exist characterising interrelationships among neurons within pools of which plasticity of a single neuron is able to maintain integration processes of the whole system. The neurons under study seem to become united into various functional blocks during different phases of conditioned behaviour which determines a formation of a dominant condition of the centres and vectors of a specific behavioural action in a given situation and at a given time.


Assuntos
Comportamento Animal/fisiologia , Córtex Cerebral/fisiologia , Animais , Condicionamento Clássico/fisiologia , Comportamento Alimentar/fisiologia , Atividade Nervosa Superior/fisiologia , Plasticidade Neuronal/fisiologia , Neurônios/fisiologia
10.
Neurosci Behav Physiol ; 25(1): 63-70, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7777148

RESUMO

In this paper the results of investigations of the participation of caudate nucleus neurons in the decision-making process and the process of organization of the program of a future motor response during the performance by Macaca mulatta monkeys of a delayed spatial choice tasks of varying degrees of complexity are presented. The presence in the caudate nucleus of spatially selective neurons, which are subdivided into two groups, was established: the position of conditional signals is reflected in the activity of one of the groups, and the direction of the future motor response is reflected in the activity of the other. The decision-making process is reflected in the impulse activity of neurons of the head of the caudate nucleus in two of its aspects: as the formation or choice of a specific motor program (spatially selective activity) and as a transitional factor from the instructive to the executive phase of the behavior.


Assuntos
Núcleo Caudado/fisiologia , Tomada de Decisões , Neurônios/fisiologia , Percepção Espacial/fisiologia , Animais , Núcleo Caudado/citologia , Comportamento de Escolha/fisiologia , Condicionamento Operante/fisiologia , Macaca mulatta , Microeletrodos
12.
Fiziol Zh Im I M Sechenova ; 80(1): 31-40, 1994 Jan.
Artigo em Russo | MEDLINE | ID: mdl-7522766

RESUMO

Spatial-selective neurons were found in the monkey caudate nucleus, the neurons being divided into two groups: one of them reflects the location of conditioned signals, the other--the direction of future motor response. The decision-making process is reflected in the unit activity in two aspects: as formation or choice of a concrete motor program, and as a transitory moment from instructive to executive phase of the behaviour.


Assuntos
Núcleo Caudado/fisiologia , Comportamento de Escolha/fisiologia , Tomada de Decisões/fisiologia , Atividade Motora/fisiologia , Neurônios/fisiologia , Tempo de Reação/fisiologia , Comportamento Espacial/fisiologia , Animais , Macaca mulatta , Microeletrodos , Fatores de Tempo
14.
Artigo em Russo | MEDLINE | ID: mdl-1647588

RESUMO

A greater part (64%) of recorded neurones of the caudate nucleus head changed its activity at various stages of fulfillment by the monkey of the task of delayed spatial choice. Most of them (46.5% of all studied) reacted at key depressing and/or taking food from the feeder. During signal presentation and with delay the frequency of impulse activity changed respectively in 17% and 14% of the studied neurones. Besides, 2 neurones had spatially-selective activity in the instructive period of the program. It can be suggested that caudate neurones participate in realization of the delayed behaviour not only during motor response fulfillment but in the instructive period as well--at the stage of perception and processing of the visual information and its storing in short-term memory.


Assuntos
Comportamento Animal/fisiologia , Núcleo Caudado/fisiologia , Neurônios/fisiologia , Tempo de Reação/fisiologia , Animais , Condicionamento Clássico/fisiologia , Macaca mulatta , Comportamento Espacial , Fatores de Tempo
16.
Artigo em Russo | MEDLINE | ID: mdl-3673398

RESUMO

A total of 714 brains from patients of predominantly advanced age who died in mental (n = 546) and somatic (n = 168) institutions have been examined macro- and microscopically. It has been found on the basis of accurate postmortem verification of Alzheimer's disease (AD) and senile dementia (SD) that in 20% of cases psychiatrists erroneously diagnose feeblemindedness in old age and in about the same proportion of cases they fail to diagnose the actual disease (most often AD and SD). The author has revealed a marked hyperdiagnosis of hypophrenias of vascular genesis at the expense of AD and SD whose rates are obviously underreported and which play a greater role in gerontopsychiatric practice than is generally accepted.


Assuntos
Doença de Alzheimer/diagnóstico , Demência/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Encéfalo/patologia , Demência/patologia , Erros de Diagnóstico , Humanos , Pessoa de Meia-Idade
17.
Artigo em Russo | MEDLINE | ID: mdl-4036431

RESUMO

Two hundred and fifty-five cases of dementia of advanced age were studied. In 142 of them (56%) the clinical diagnosis was vascular dementia. In 55 the anatomical diagnosis was senile dementia or Alzheimer's disease and in only 40 cases with established multiple infarcts (in 38 cases they were localized in the area of the subcortical ganglia) the diagnosis was multiinfarction dementia. In 11 of these 40 cases, multiinfarction dementia was combined with senile dementia and Alzheimer's disease. In relation to all 255 studied dementias of advanced age multiinfarction dementia constituted 11% in its pure form and 18% in its mixed form.


Assuntos
Demência/diagnóstico , Doença de Alzheimer/complicações , Doença de Alzheimer/diagnóstico , Encéfalo/patologia , Demência/complicações , Demência/patologia , Erros de Diagnóstico , Humanos , Arteriosclerose Intracraniana/complicações
19.
Artigo em Russo | MEDLINE | ID: mdl-4024803

RESUMO

An electron microscopy study was conducted on the material of biopsies from the removed epileptic foci localized in the hippocamp and fields 21 and 38 of the temporal cortex of 11 patients with temporal epilepsy. There was the constant presence of so-called dark and altered light neurocytes whose cytoplasm had experienced considerable changes and was saturated with various inclusions. The axons and dendrites of the cells underwent peculiar degeneration. The authors revealed multiple agglutination of synaptic vesicles in the preterminals and synaptic buds, and also dark degeneration of the axonal endings in the absence of Waller's degeneration of axons. Marked changes in the walls of the capillaries were also found.


Assuntos
Epilepsia do Lobo Temporal/patologia , Hipocampo/ultraestrutura , Lobo Temporal/ultraestrutura , Adolescente , Adulto , Axônios/ultraestrutura , Capilares/ultraestrutura , Criança , Dendritos/ultraestrutura , Humanos , Microscopia Eletrônica , Organoides/ultraestrutura , Sinapses/ultraestrutura
20.
Arkh Anat Gistol Embriol ; 87(12): 8-11, 1984 Dec.
Artigo em Russo | MEDLINE | ID: mdl-6525057

RESUMO

The investigation has been performed in the human brain of persons at the age of 75-87 years, in the auditory cortex of old cats and in bioplates obtained from epileptic foci of the hippocamp and the temporal cortex of 11 patients suffering from temporal epilepsy (at the age of 12-29 years). Distal parts of the dendrites contain a large amount of myelin-like membranous and electron opaque inclusions. In most cases these dendrites have no axodendritic contacts. In large trunks of the dendrites there are noted a comparatively large number of neurotubules with definitely seen contours against the background of small conglomerates of loose fine fibrillar material. Myelin axons contain a large amount of sharply contoured neurotubules which fill axoplasm. Similar dendrites and axons are revealed in the cerebral cortex both at age changes and in tissue of the epilepsy foci. These changes are supposed to result from the effect of the same factor.


Assuntos
Encéfalo/ultraestrutura , Epilepsia do Lobo Temporal/patologia , Adolescente , Adulto , Idoso , Envelhecimento , Animais , Córtex Auditivo/ultraestrutura , Axônios/ultraestrutura , Gatos , Córtex Cerebral/ultraestrutura , Criança , Dendritos/ultraestrutura , Hipocampo/ultraestrutura , Humanos , Lobo Temporal/ultraestrutura
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