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1.
Natl Med J India ; 34(5): 302-305, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35593241

RESUMEN

The future of Indian students who return as 'foreign medical graduates' (FMG) after training in certain countries is often uncertain. We collected data from newspapers, government resources and agencies involved in handling this issue. We analysed the current status of medical education in India, the Commonwealth of Independent States (CIS) and some neighbouring countries. Of approximately 1.4 million (14 lakh) students taking the National Eligibility cum Entrance Test (NEET), about 5.8% get admission in medical colleges. There are about 554 medical colleges in India with 82 550 MBBS seats, 51.9% seats belong to the government quota. Parents who send their children to a foreign country to do medicine spend ₹1.5 million (15 lakh) tò4 million (40 lakh) against an estimated annual income of ₹1.2 million (12 lakh) and the child spends 4-6 years in a foreign country. Of 38 150 FMGs who took the examinations conducted by the National Board of Examinations from 2015 to 2018, 18.9% passed the FMG examination mandatory for registration to practise medicine in India. The National Medical Commission is trying to solve this issue by removing the age bar for entry to MBBS and recommending lowering of fees for MBBS in government quota. Seeking graduation in medical colleges outside India may not be advisable for those from the middle/ low-income group of India.


Asunto(s)
Educación Médica , Médicos Graduados Extranjeros , Niño , Humanos , India
2.
Phys Rev Lett ; 112(2): 025002, 2014 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-24484021

RESUMEN

We present the first results from an experimental campaign to measure the atomic ablator-gas mix in the deceleration phase of gas-filled capsule implosions on the National Ignition Facility. Plastic capsules containing CD layers were filled with tritium gas; as the reactants are initially separated, DT fusion yield provides a direct measure of the atomic mix of ablator into the hot spot gas. Capsules were imploded with x rays generated in hohlraums with peak radiation temperatures of ∼294 eV. While the TT fusion reaction probes conditions in the central part (core) of the implosion hot spot, the DT reaction probes a mixed region on the outer part of the hot spot near the ablator-hot-spot interface. Experimental data were used to develop and validate the atomic-mix model used in two-dimensional simulations.

3.
Am J Transplant ; 13(11): 3010-20, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24102808

RESUMEN

Regulatory T cell (Treg) therapy has the potential to induce transplantation tolerance so that immunosuppression and associated morbidity can be minimized. Alloantigen-reactive Tregs (arTregs) are more effective at preventing graft rejection than polyclonally expanded Tregs (PolyTregs) in murine models. We have developed a manufacturing process to expand human arTregs in short-term cultures using good manufacturing practice-compliant reagents. This process uses CD40L-activated allogeneic B cells to selectively expand arTregs followed by polyclonal restimulation to increase yield. Tregs expanded 100- to 1600-fold were highly alloantigen reactive and expressed the phenotype of stable Tregs. The alloantigen-expanded Tregs had a diverse TCR repertoire. They were more potent than PolyTregs in vitro and more effective at controlling allograft injuries in vivo in a humanized mouse model.


Asunto(s)
Tratamiento Basado en Trasplante de Células y Tejidos , Rechazo de Injerto/prevención & control , Tolerancia Inmunológica/inmunología , Isoantígenos/inmunología , Trasplante de Piel , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/trasplante , Animales , Citometría de Flujo , Rechazo de Injerto/inmunología , Enfermedad Injerto contra Huésped/inmunología , Enfermedad Injerto contra Huésped/prevención & control , Humanos , Activación de Linfocitos , Ratones , Ratones Endogámicos BALB C , Tolerancia al Trasplante
4.
Phys Rev Lett ; 104(5): 056102, 2010 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-20366775

RESUMEN

Many of the surface phenomena are driven by elastic energy and elastic interactions. Despite the fact that there are many microscopic techniques with nm and atomic resolution, an established technique to study the distribution of strain on the surface is still lacking. We present a study on the Gd(0001)/W(110) system, in which undulations in the Gd layer are detected by STM. This creates a heterogeneous surface with reduced strains, due to relaxation, on the crests of the waved surface and elevated strains in the troughs. An additional part of the strain is released through Stransky-Krastanov growth of Gd islands. Utilizing a strain-relief model, we show that the island size and shape reflect the strain variations on the surface. Strain maps were calculated, using the island as nanoprobes, with good correlation to the surface topography.

5.
J Med Genet ; 40(2): 96-103, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12566517

RESUMEN

INTRODUCTION: Interaction between genetic background and oxidative environmental stimuli in the pathogenesis of human lung disease has been largely unexplored. METHODS: A prospective epidemiological study was undertaken in 253 coal miners. Intermediate quantitative phenotypes of response to oxidant exposure, including erythrocyte glutathione peroxidase (GSH-Px) and catalase activities, were studied. Oxidant exposures studied were smoking habits and cumulative dust exposure assessed by job history and ambient measures. Disease phenotypes included subclinical computed tomography score at the first survey and x ray profusion grades twice, five years apart, to assess established coal workers' pneumoconiosis (CWP). Miners were genotyped for common functional polymorphisms in the gene for tumour necrosis factor alpha (TNF) and lymphotoxin alpha (LTA), two proinflammatory cytokines that have been implicated in the pathogenesis of chronic lung diseases. RESULTS: Regarding gene-environment interaction on intermediate phenotypes, results showed interaction of a promoter polymorphism at the -308 position in TNF with occupational exposure on erythrocyte GSH-Px activity with a significant association in those with high exposure (p=0.003), whereas no association was observed among those with low exposure (interaction p=0.06). Regarding gene intermediate phenotype interaction on clinical outcome, results showed an association of CWP prevalence with an NcoI polymorphism in LTA in those with low catalase activity (p=0.05), whereas no association was observed in those with high activity (interaction p=0.03). No other significant association was observed. CONCLUSION: The results suggest that interactions of genetic background with environmental exposure and intermediate response phenotypes are important components in the pathogenesis of CWP.


Asunto(s)
Catalasa/metabolismo , Minas de Carbón , Glutatión Peroxidasa/metabolismo , Linfotoxina-alfa/genética , Factor de Necrosis Tumoral alfa/genética , Exposición a Riesgos Ambientales/efectos adversos , Eritrocitos/efectos de los fármacos , Eritrocitos/enzimología , Francia/epidemiología , Genotipo , Humanos , Estudios Longitudinales , Persona de Mediana Edad , Exposición Profesional/efectos adversos , Oxidantes/efectos adversos , Estrés Oxidativo , Fenotipo , Neumoconiosis/epidemiología , Neumoconiosis/etiología , Polimorfismo Genético , Prevalencia , Estudios Prospectivos
6.
J Neuropathol Exp Neurol ; 56(9): 974-87, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9291939

RESUMEN

Progressive central nervous system dysfunction analogous to the AIDS dementia complex (ADC) seen in adults (HIV-1-associated progressive encephalopathy or HIV-1 encephalopathy) commonly occurs in HIV-1-infected children. The cause appears to be directly or indirectly related to HIV-1, rather than to other opportunistic pathogens. The exact mechanism(s) by which the virus affects brain function is not known. To determine whether the virus might modify brain function via an alteration in cortical neurons, we examined peptide neurotransmitter expression in the frontal cortex of HIV-1-infected cases with clinical HIV-1 encephalopathy relative to pathologic HIV-1 encephalitis. In situ hybridization was used to determine the level of peptide neurotransmitter expression of somatostatin in the frontal cortex of cases with and without HIV-1 encephalopathy and/or HIV-1 encephalitis. A 2-fold higher number of preprosomatostatin mRNA-positive interneurons was present in layer IV of cases with HIV-1 encephalitis compared with cases without HIV-1 encephalitis. In cases with PE, this neuronal alteration was 4- to 5-fold higher than in cases without PE, and was present in subcortical white matter in addition to layer IV. In cases having both PE and HIV-1 encephalitis, and in cases with HIV-1 encephalitis alone, these neuronal alterations in layer IV and/or subcortical white matter related to disseminated microglial nodules, even when these potentially viral-infected cells were negative for HIV-1 p24 antigen, a marker of productive viral infection. An alteration in preprosomatostatin mRNA-expressing cells occurring with HIV-1 encephalitis may be at least one mechanism that contributes to HIV-1 encephalopathy. When compared with other cortical laminae, layer IV receives most of its synaptic input from the mediodorsal nucleus of the thalamus. Neurons in the subcortical white matter project to the thalamus. The thalamus has been shown to have high amounts of viral antigen and increased metabolic activity in patients with AIDS. An alteration in preprosomatostatin mRNA-expressing cells may play a role in HIV-1 encephalopathy.


Asunto(s)
Complejo SIDA Demencia/patología , Encefalitis Viral/patología , Encefalitis Viral/virología , Lóbulo Frontal/patología , Infecciones por VIH/patología , VIH-1 , Neuronas/patología , Complejo SIDA Demencia/metabolismo , Niño , Preescolar , Encefalitis Viral/metabolismo , Femenino , Lóbulo Frontal/metabolismo , Infecciones por VIH/metabolismo , Humanos , Lactante , Masculino , Neuronas/metabolismo , Precursores de Proteínas/genética , ARN Mensajero/metabolismo , Somatostatina/genética , Somatostatina/metabolismo
7.
Biol Psychiatry ; 29(3): 265-72, 1991 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-2015331

RESUMEN

Decreased amplitudes of late components of event-related potentials (ERPs) in schizophrenia were ascribed to either psychotic features or to neuroleptic treatment of the patients. To rule out the drug effect, ERPs to stroboscopic stimuli were recorded in drug-naive schizophrenics and control subjects during no-task and simple-task sessions. Patients had significantly lower amplitudes of the late ERP components during both sessions, thus confirming similar results with treated schizophrenics. On the other hand, drug-naive patients did not differ from controls in the task-related relative facilitation of late ERP components. These results differ from findings of minimal ERP facilitation to task in treated schizophrenics. This discrepancy is discussed in the context of the effects of neuroleptic treatment and task demands on ERPs.


Asunto(s)
Nivel de Alerta/fisiología , Atención/fisiología , Electroencefalografía , Potenciales Evocados Visuales/fisiología , Esquizofrenia/fisiopatología , Psicología del Esquizofrénico , Adulto , Anciano , Mapeo Encefálico , Corteza Cerebral/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tiempo de Reacción/fisiología
8.
Biol Psychiatry ; 16(2): 131-44, 1981 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7225482

RESUMEN

Asymmetries in saccadic pursuit were studied, using EOG, ion 20 schizophrenic patients, as well as in two groups of normal subjects, screened for their patterns of lateral eye movements (LEM). Tracking performance was also examined while subjects were concurrently engaged in performing a cognitive task. Saccadic pursuit among schizophrenic patients was replicated in the present study. No asymmetry was observed in the quality of leftward as compared to rightward tracking. However, solving syllogisms while tracking resulted in further deterioration in tracking performance of the patients, with significantly more saccades and arrests in tracking occurring when following the target to the left as compared to rightward following. Similar asymmetry was observed in one group of controls who are believed to rely more on their left hemisphere on the LEM test, whereas no asymmetry was observed in the performance of the second control group. These results are interpreted as supporting the hypothesis of left hemispheric hyperactivity in schizophrenia. Saccadic pursuit in one subgroup of the normal sample is considered as suggesting that these individuals belong to the high-risk group.


Asunto(s)
Movimientos Oculares , Esquizofrenia/fisiopatología , Adolescente , Adulto , Femenino , Lateralidad Funcional , Humanos , Masculino , Procesos Mentales , Enfermedad de Parkinson/fisiopatología , Riesgo
9.
Biol Psychiatry ; 17(7): 815-28, 1982 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6126228

RESUMEN

Electrophysiological studies have shown asymmetric brain reactivity in schizophrenia, supporting the hypothesis of left hemisphere hyperarousal in this disease. It may be assumed, therefore, that neuroleptic treatment restores hemispheric balance in schizophrenic patients by selectively suppressing the hyperactive left hemisphere. This hypothesis was tested in the present study which compared bilaterally recorded visual evoked potentials (VEP) in 9 non-medicated patients and 29 schizophrenics treated with various neuroleptic drugs, as well as in 34 normal controls. In medicated patients later VEP components showed enhancement over the right hemisphere as a function of the overall dose (chlorpromazine equivalent) of neuroleptics. Reversed asymmetry was seen in drug-free patients. In view of this result, some amendments of the concept of left hemisphere hyperactivity in schizophrenia are proposed.


Asunto(s)
Antipsicóticos/farmacología , Encéfalo/efectos de los fármacos , Potenciales Evocados Visuales/efectos de los fármacos , Esquizofrenia/fisiopatología , Adolescente , Adulto , Encéfalo/fisiopatología , Femenino , Lateralidad Funcional , Humanos , Masculino , Piperazinas/farmacología , Esquizofrenia/tratamiento farmacológico
10.
Biol Psychiatry ; 37(6): 402-9, 1995 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-7772649

RESUMEN

In a previous study we recorded visual event-related potentials (ERP) in drug-naive schizophrenics during passive-attention and active-attention tasks. Patients, compared to normal controls, had much lower late positive components (LPC) in both sessions, but nearly normal LPC increase from passive to active task. The present sample consisted of drug-naive and drug-free patients who were tested before and during the first month of neuroleptic treatment. Neuroleptics initiated gradual amelioration of psychiatric symptoms expressed by reduced Brief Psychiatric Rating Scale (BPRS) scores. Schizophrenics compared to controls showed a session-related increase in LPC amplitude, but this process of LPC recovery was too minor to fully normalize the low LPC amplitudes in patients. Furthermore, the treatment either did not improve or even reduce the LPC reaction to the active-attention task. These findings indicate that normalization of low LPC in schizophrenia might require a long period of treatment, and that patients' reduced LPC reactivity to the task might be contributed, rather than treated, by neuroleptics.


Asunto(s)
Antipsicóticos/administración & dosificación , Nivel de Alerta/efectos de los fármacos , Atención/efectos de los fármacos , Potenciales Evocados Visuales/efectos de los fármacos , Esquizofrenia/tratamiento farmacológico , Psicología del Esquizofrénico , Adulto , Anciano , Esquema de Medicación , Electroencefalografía/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Estándares de Referencia
11.
Biol Psychiatry ; 26(7): 677-89, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2804189

RESUMEN

This study of 51 prepubertal psychiatric inpatients evaluates plasma cortisol measurements at 8 AM, 4 PM, and 11 PM before and after dexamethasone was administered in counterbalanced order at doses of 0.5 mg and 1.0 mg. Approximately 76.5% of the children had an affective disorder. Major depressive disorder was associated with higher plasma cortisol levels than other disorders. Pre- and postdexamethasone plasma cortisol levels using 0.5 mg dexamethasone exhibited a circadian variation. The optimal criterion for cortisol nonsuppression was 5 micrograms/dl measured at 8 AM after administration of 0.5 mg dexamethasone.


Asunto(s)
Trastorno Depresivo/diagnóstico , Dexametasona , Hidrocortisona/sangre , Niño , Trastorno Depresivo/sangre , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Trastornos Psicóticos/diagnóstico
12.
Neurology ; 47(6): 1583-5, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8960752

RESUMEN

Five children with human immunodeficiency virus type-1 (HIV-1) infection, aged 4 to 13 years, manifested extrapyramidal dysfunction characterized by rigidity/stiffness, ambulation difficulties/shuffling gait, dysarthria/drooling/swallowing dysfunction, hypomimetic/inexpressive facies, and bradykinesia. Levodopa therapy caused an initial improvement in all symptoms, and the effect was sustained in most patients. Levodopa is a useful adjunctive therapy in HIV-1-infected children with extrapyramidal syndromes, by enhancing motor function and improving their quality of life.


Asunto(s)
Infecciones por VIH/fisiopatología , Levodopa/uso terapéutico , Trastornos del Movimiento/tratamiento farmacológico , Preescolar , Femenino , Humanos , Masculino , Trastornos del Movimiento/fisiopatología , Síndrome
13.
Neurology ; 44(3 Pt 1): 474-81, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8145918

RESUMEN

In previous studies, using polymerase chain reaction amplification of HIV-1 genes directly from pathologic tissues of children who died with AIDS encephalopathy, we showed that the reading frame of the HIV-1 regulatory nef gene is open, suggesting that the nef protein was expressed. We now show, using immunocytochemistry and in situ hybridization with nef-specific probes in postmortem pediatric CNS tissues, that nef mRNA and protein are present in up to 20% of astrocytes in tissue sections selected for extensive histopathology. By contrast, HIV-1 structural proteins such as gag and their coding mRNAs are present in multinucleated giant cells that harbor productive infection and are the hallmark of HIV-1 infection in the CNS. These findings are consistent with the nonproductive infection of glial cells observed in vitro, and imply that HIV-1 infection of astrocytes is restricted to early regulatory gene products, of which nef is the best target as it is expressed at high levels and is membrane-anchored. In developing central nervous tissues of children, restricted and latent HIV-1 infection of astrocytes may be extensive and contribute significantly to HIV-1 neuropathogenesis.


Asunto(s)
Astrocitos/microbiología , Encéfalo/microbiología , Genes nef , Infecciones por VIH/microbiología , VIH-1/genética , Médula Espinal/microbiología , Anciano , Encéfalo/patología , Niño , Preescolar , Femenino , Regulación Viral de la Expresión Génica , Infecciones por VIH/patología , Humanos , Inmunohistoquímica , Hibridación in Situ , Lactante , Masculino , Persona de Mediana Edad , Médula Espinal/patología , Factores de Tiempo
14.
Psychopharmacology (Berl) ; 77(2): 168-70, 1982.
Artículo en Inglés | MEDLINE | ID: mdl-6126905

RESUMEN

Studies measuring reflective lateral eye movements (LEM) in schizophrenic patients revealed predominance of rightward LEMS, which was interpreted as suggesting left hemisphere overactivation in schizophrenia. In the present study LEM behaviour of medicated schizophrenics was compared to that of non-medicated patients. Rightward LEMs were predominant in a group of patients treated with phenothiazines with piperazine side chains, whereas among schizophrenics treated with non-piperazine drugs leftward LEMs were more predominant. This finding suggests that previous reports on LEM directionality in schizophrenia may have been confounded by neuroleptic medication. The possible effect of piperazine derivatives on hemispheric balance is discussed.


Asunto(s)
Antipsicóticos/efectos adversos , Lateralidad Funcional/fisiología , Esquizofrenia/fisiopatología , Adulto , Antipsicóticos/uso terapéutico , Electrooculografía , Femenino , Humanos , Masculino , Esquizofrenia/tratamiento farmacológico
15.
Obstet Gynecol ; 62(1): 131-3, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6682947

RESUMEN

The diagnosis of puerperal ovarian vein thrombophlebitis by computed axial tomography (CAT) scan is reported. The characteristic finding, ie, a soft tissue mass with a diameter of 2 cm and length of 14 cm, extending from the uterine cornua to the level of the renal vein, can be seen by CAT scan. The near total resolution of the mass on follow-up CAT scan confirmed successful treatment with antibiotics and heparin. Observation of these findings will allow future cases to be definitively diagnosed and treated without invasive procedures.


Asunto(s)
Ovario/irrigación sanguínea , Trastornos Puerperales/diagnóstico por imagen , Tromboflebitis/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Femenino , Humanos , Embarazo
16.
Obstet Gynecol ; 55(3): 309-14, 1980 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7360428

RESUMEN

Ocular fundi of 410 newborns were examined for retinal hemorrhages within 24 hours after delivery. The purpose of this study was to investigate whether the course of pregnancy and management of delivery influence the incidence of neonatal retinal hemorrhage (RH) and whether this incidence could be reduced by electronic monitoring of delivery. To assess the prognostic value of neonatal RH for future development of the child, the physical, motor, and psychologic states of 252 infants were examined 6 to 18 months following delivery. The incidence of RH was 37.3% and was not influenced by maternal age, parity, gestational age, course of pregnancy, birth weight, or electronic monitoring of delivery. The mode of delivery did influence the incidence of RH. Gesell developmental schedule showed no correlation between ocular findings and later development of the child.


Asunto(s)
Hemorragia Retiniana/congénito , Parto Obstétrico , Femenino , Estudios de Seguimiento , Humanos , Recién Nacido , Presentación en Trabajo de Parto , Embarazo , Pronóstico , Hemorragia Retiniana/etiología
18.
Behav Brain Res ; 18(3): 285-8, 1985 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-4091964

RESUMEN

Contrast (pattern-reversal) visual evoked potentials (VEPs) were examined in the awake rabbit to test the possibility that carotid occlusion would disrupt sensory transmission in the visual pathways. Rabbits were operated to ligate one carotid and to chronically transplant another one into a skin flap. VEPs to checkerboard stimuli reversing with a rate of 2/s were recorded from the visual cortex. No significant changes in latency, amplitude and waveshape of VEPs were noted after 3-30 min of carotid occlusion. Apparently, blood flow from the basilar system can be easily shunted via the circle of Willis to the territory of the internal carotid.


Asunto(s)
Enfermedades de las Arterias Carótidas/fisiopatología , Potenciales Evocados Visuales , Vías Visuales/fisiopatología , Percepción Visual/fisiología , Animales , Chinchilla , Circulación Colateral , Constricción Patológica/fisiopatología , Conejos , Ratas , Tiempo de Reacción/fisiología , Especificidad de la Especie
19.
Behav Brain Res ; 98(1): 45-51, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10210521

RESUMEN

The study departs from the finding that postural asymmetries in low-weight female neonates are greatly increased following prenatal lesions inflicted by gamma irradiation at day 15. Given that amphetamine-induced rotation in adult rats could be predicted by their infantile axial asymmetry we expected a greater tendency for circling in rats exposed at day 15. To examine this prediction, Sprague-Dawley rats were exposed to a single dose of gamma radiation at 1.5 Gy with a dose-rate of 0.15 Gy/min. The dose was delivered on one of the embryonic days (E15, 17 or 19) throughout the whole body of pregnant dams. Sham prenatal exposure of controls consisted of placing pregnant rats in the same environment for 10 min. All rats were tested during the active part of the circadian cycle. At postnatal day 27 (P27) exposed pups did not differ in rates of either spontaneous or d-amphetamine-induced circling from the shams. At P57, in keeping with our prediction, E15 rats manifested enhanced rotation and higher net asymmetry. However, E17 also showed higher gyration tendency compared to their shams while exposed E19 rats did not differ from their shams. The role of intrinsic DAergic imbalance presumably sharpened by irradiation at E15 and of neocortical deficit inflicted at E15 and E17 are discussed.


Asunto(s)
Actividad Motora/efectos de la radiación , Orientación/efectos de la radiación , Efectos Tardíos de la Exposición Prenatal , Maduración Sexual/efectos de la radiación , Conducta Estereotipada/efectos de la radiación , Animales , Mapeo Encefálico , Dominancia Cerebral/efectos de la radiación , Femenino , Rayos gamma , Edad Gestacional , Masculino , Neocórtex/efectos de la radiación , Embarazo , Ratas , Ratas Sprague-Dawley , Receptores Dopaminérgicos/efectos de la radiación
20.
Behav Brain Res ; 17(3): 257-63, 1985 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-4084396

RESUMEN

Several studies have demonstrated the existence of crossed pathways interconnecting the bilateral extrapyramidal system. The present study has evaluated the role of the thalamus in the interhemispheric control of nigrostriatal function by observing the effect of midsagittal thalamic transection on amphetamine-induced rotation in rats. The effect of thalamic transection on net rotational asymmetry did not differ from the effects of sham operations. Also, the transection did not affect the rotational asymmetry induced by subsequent lesioning of the dominant hemisphere substantia nigra. The failure to affect the rotation asymmetry by the transection suggests either that the inter-hemispheric pathway does not control extrapyramidal asymmetry or that the crossing takes place outside the thalamus. In an additional group of rats, thalamic transection did not interrupt retrograde labeling of somata in the substantia nigra and ventral tegmental area by horseradish peroxidase injected in the contralateral caudate. Thus, the crossed nigrostriatal projection does not decussate via the thalamus. It is suggested that this pathway decussates in the ventral mesencephalon.


Asunto(s)
Conducta Animal/fisiología , Lateralidad Funcional/fisiología , Actividad Motora/fisiología , Sustancia Negra/fisiología , Tálamo/fisiología , Anfetamina/farmacología , Animales , Peroxidasa de Rábano Silvestre , Masculino , Compresión Nerviosa , Vías Nerviosas/fisiología , Ratas , Ratas Endogámicas
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