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101.
Neurological prognosis correlated with variations over time in the number of subependymal nodules in tuberous sclerosis 总被引:2,自引:0,他引:2
In tuberous sclerosis (TS), brain CT reveals subependymal nodules, cortical tubers and white matter lesions. This study is a retrospective analysis of the relationship between the variations over time in the number of subependymal nodules and the clinical course in cases of tuberous sclerosis. Twenty-four children with tuberous sclerosis, who attended the National Children's Hospital as outpatients, were followed by means of brain CT examinations for 7 years and 1 month on average. Cranial MRI was also performed in 22 cases. Brain CT disclosed subependymal nodules already in early infancy. In almost all cases, the number of subependymal nodules gradually increased with age, especially around the frontal horn of the lateral ventricle. The increase stopped at around age 10. The cases with five or more subependymal nodules at the initial or subsequent CT examination (17 patients; Group A) exhibited a significantly greater number of cortical tubers than those with less than five (five patients; Group B) and had white matter lesions unlike Group B. In addition, the number of cases with either infantile spasms or mental retardation was significantly higher in Group A than Group B (P<0.005). In conclusion, the number of ventricular subependymal nodules may allow prediction of the severity of the cerebral dysfunction in TS. Our results suggest that its variation may reflect the degree of the embryologic disorder when neuronal cells grow in the early gestational period. 相似文献
102.
The possibility of a direct projection from the perirhinal cortex (PER) to areas CA1 and subiculum (SUB) in the hippocampus has been suggested on the basis of tracer studies, but this projection has not unequivocally been supported by physiological studies. The demonstration of such a functional pathway might be important to understand the functioning of the hippocampal memory system. Here we present physiological and further anatomical evidence for such a connection between PER and the hippocampus. Electrical stimulation of PER in vivo evoked field potentials (EFPs) at the border area of CA1/SUB, consisting of a short latency and a longer latency component. Current source density analysis revealed that the sink of the short latency component was situated in the molecular layer of area CA1/SUB, while the longer latency component had its sink in the outer molecular layer of the dentate gyrus (DG). Anterograde tracer injections in PER showed labelled fibres in the border area of CA1/SUB, but anatomical evidence for a projection of PER to DG was not found. When synaptic transmission in the entorhinal cortex was partly blocked, the amplitude of the longer latency component of the recorded EFPs in the hippocampus was decreased while the short latency component was not affected, which suggests that the indirect pathway originating in PER is mediated through a synaptic relay in the entorhinal cortex. From the present results we conclude that information originating in PER reaches area CA1/SUB by parallel, direct and indirect, routes. The existence of this parallel organization appears to form an essential feature for the proper function of the medial temporal lobe memory system. 相似文献
103.
Paolo Bongioanni Francesco Lombardo Cristina Fioretti Giuseppe Meucci 《Journal of neurology》1996,243(8):605-610
Multiple sclerosis (MS) is a T-cell-mediated autoimmune demyelinating disease of the central nervous system (CNS), associated with an altered immunoregulation. Interferon (IFN)-, also known as immune IFN, is a cytokine with several effects on the immune system. Specific IFN- receptors have been found on human lymphocytes, as well as on other cell types (e.g. gliocytes), even in the CNS. The aim of the present study was to evaluate IFN- binding on peripheral blood T-lymphocytes from MS patients, compared with those from healthy subjects. Thirty-two patients were selected according to the classical criteria for definite MS; as controls, 21 healthy subjects were studied. We have found that T-lymphocytes from MS patients bear a significantly smaller amount of IFN- receptors than those from controls [B
max: 568, 18 vs 708, 14 (mean, SE) receptors/cell]. Such IFN- binding sites are of the same type in patients and healthy subjects [K
d: 1.0, 0.05 vs 0.9, 0.02 (mean, SE) nM]. These findings are discussed in terms of immunopathogenesis of MS, since it has been reported that activated T-lymphocytes have decreased amounts of IFN- receptors. 相似文献
104.
F. F. Cruz-Sánchez A. Moral M. L. Rossi L. Quintó C. Castejón E. Tolosa J. de Belleroche 《Journal of neural transmission (Vienna, Austria : 1996)》1996,103(11):1317-1329
Summary Aged-related spinal cord changes such as neuronal loss have been related to the degree of clinical severity of amyotrophic lateral sclerosis (ALS); morphological data on synapses are, however, wanting. Variations in synaptophysin (Sph) expression in aging and ALS were thus studied at the level of lower motor neurons in 40 controls with non-neurological diseases and 11 cases of ALS. Control sections of formalin fixed paraffin embedded cervical (C7/8), thoracic (T10) and lumbar spinal cord (L5) and C6, C7, C8 and L5 of ALS cases were stained with haematoxylin and eosin, luxol fast blue (LFB), and immunostained with a mouse monoclonal antibody against Sph. The neuropil of the anterior horn (AH) in all control cases demonstrated Sph positivity. A dot-like pattern of positivity of presynaptic terminals on soma of motor neurons and fine immunoreactivity along neuronal processes were observed. A significant reduction of Sph immunostaining was observed in the neuropil with increasing age and 3 different somatic patterns were seen: a-well preserved Sph reactivity around the soma and the proximal dendrites of histologically normal neurons; b-few chromatolytic neurons showing large numbers of dot-like presynaptic terminals around the cell body and in a fused pattern; c-intense, diffuse, and homogeneous reactivity of some neurons. Attenuation of Sph reactivity in the AH neuropil, to its complete loss, was observed in all ALS cases. In addition to patterns a-c, two additional microscopic findings were noted in ALS: d-chromatolytic neurons showing complete absence of Sph reactivity; e-absence of Sph reactivity around the soma and the proximal dendrites of histologically normal surviving neurons.Our findings demonstrate that there is a decrease in Sph immunostaining with aging, thus suggesting an alteration in dendritic networks of the AH with aging. Changes in the pattern of Sph immunoreactivity in cell bodies may represent synaptic plasticity and/or degeneration. Reinnervation may also be a possible mechanism as a response to neuronal loss in oldest control cases. Sph reactivity results may thus lend support to the presence of superimposed aging components in ALS cases which may give an insight into explaining the increasing severity of the disease which is encountered with advancing age. 相似文献
105.
Jan Lycke Bo Svennerholm Elisabeth Hjelmquist Lars Frisén Gaby Badr Mats Andersson Anders Vahlne Oluf Andersen 《Journal of neurology》1996,243(3):214-224
Acyclovir treatment was used in a randomized, double-blind, placebo-controlled clinical trial with parallel groups to test the hypothesis that herpes virus infections are involved in the pathogenesis of multiple sclerosis (MS). Sixty patients with the relapsing-remitting form of MS were randomized to either oral treatment with 800 mg acyclovir or placebo tablets three times daily for 2 years. The clinical effect was investigated by an extensive test battery consisting of neurological examinations, neuro-ophthalmological and neuropsychological tests, and evoked potentials. Results were based on intent-to-treat data and the primary outcome measure was the exacerbation rate. In the acyclovir group (n = 30), 62 exacerbations were recorded during the treatment period, yielding an annual exacerbation rate of 1.03. The placebo group (n = 30) had 94 exacerbations and an annual exacerbation rate of 1.57. Thus, 34% fewer exacerbations were encountered during acyclovir treatment. This difference in exacerbation rate between the treatment groups was not significant (P = 0.083). However, this trend to a lower disease activity in acyclovir-treated patients was supported in subsequent data analysis. If the patients were grouped according to exacerbation frequencies, i.e. into low (0–2), medium (3–5) and high (6–8) rate groups, the difference between acyclovir and placebo treatment was significant (P = 0.017). Moreover, in a subgroup of the population with a duration of the disease of at least 2 years providing an exacerbation rate base-line before entry, individual differences in exacerbation rates were compared between the 2-year pre-study period and the study period in acyclovir-treated (n = 19) and placebo (n = 20) patients and acyclovir-treated patients showed a significant reduction of exacerbations (P = 0.024). Otherwise, neurological parameters were essentially unaffected by acyclovir treatment and there were no convincing signs of reduced neurological deterioration in the acyclovir group. This study indicates that acyclovir treatment might inhibit the triggering of MS exacerbations and thus suggests that acyclovir-susceptible viruses might be involved in the pathogenesis of MS. This possibility warrants further investigation. 相似文献
106.
Tartaro A. Onofrj M. Delli Pizzi C. Bonomo L. Thomas A. Fulgente T. Gambi D. 《The Italian Journal of Neurological Sciences》1996,17(1):35-42
Magnetic resonance images of optic nerves were obtained in 20 patients with acute optic neuritis (ON), and assessed by means of clinical, visual field and visual evoked potential evaluations; the imaging was repeated 1 year later. The results of the conventional Short Tau Inversion Recovery (STIR) sequence obtained using short time echo (STE-STIR: 22 msec) were compared with those of the long time echo sequence (LTE-STIR: 80 msec). The conventional STE-STIR sequence revealed lesions in 57.2% cases of acute ON and in 42.9% of the optic nerves affected by previous ON: the LTE-STIR sequence was diagnostic in 95.2% of acute ON cases and in 85% of patients with previous ON. The calculated length of the optic nerve lesions was significantly longer in the images obtained using the LTE-STIR sequence than in those obtained using conventional STE-STIR sequences.
Sommario Si descrivono i risultati ottenuti con indagini di Risonanza Magnetica (RM) dei nervi ottici (eseguite all'esordio e 12 mesi dopo) in 20 pazienti affetti da Neurite Ottica (NO) acuta, valutata in funzione della sintomatologia clinica e delle alterazioni campimetriche e del potenziale evocato visivo.Sono state analizzate le immagini RM in Short Tau Inversion Recovery (STIR) mettendo a confronto i rilievi ottenuti con sequenza Short Time Echo (STE-STIR: 22 msec) rispetto a quelli ottenuti con Long Time Echo (LTE-STIR: 20 msec). Mentre con la convenzionale STE-STIR è stato possibile rilevare lesioni a carico dei nervi ottici nel 57.2% delle Neuriti Acute e nel 42.9% delle Neuriti Pregresse, la metodica LTE-STIR è risultata diagnostica nel 95.2% delle Neuriti Acute e nel 85% delle Neuriti Pregresse.Sia nelle NO acute che nelle pregresse, la lunghezza delle lesioni a carico dei nervi ottici sono risultate significativamente maggiori rispetto a quelle ottenute con la convenzionale metodica STE-STIR.相似文献
107.
108.
Summary Cyclic adenosine 3,5monophosphate (cAMP) was assayed in CSF and plasma obtained from patients with multiple sclerosis. Decreased CSF cAMP levels were found in more than half of the patients while plasma cAMP was normal. The decrease is correlated significantly with the disability of the patient and with the progression of the disease. A low CSF cAMP level can be considered as prognostically unfavorable, particularly in the early stage of the disease. There was no correlation between the cAMP levels and the duration of the disease or with bouts and remissions. ACTH therapy did not normalize the decreased values. Obviously the decrease of CSF cAMP is related to the demyelination and not to the intensity of the pathological immunoreactions.
Zusammenfassung Es wurde das cyclische Adenosin-3,5monophosphat im Liquor von Patienten mit multipler Sklerose untersucht. Bei einem Teil der Patienten wurden auch die Vergleichswerte im Blutplasma bestimmt. Es zeigte sich bei mehr als der Hälfte der Patienten eine Verminderung der cAMP-Konzentration im Liquor bei normalem Plasmaspiegel. Diese cAMP-Verminderung erwies sich als signifikant abhängig von dem Schweregrad der Erkrankung bzw. der Erkrankungsprogredienz und ist besonders in frühen Erkrankungsfällen als prognostisch ungünstiges Zeichen anzusehen. Es fand sich kein Zusammenhang mit dem Krankheitsstadium, d.h. Schub bzw. Intervall, und mit der Erkrankungsdauer. Eine ACTH-Behandlung vermochte diese Verminderung der Werte nicht auszugleichen. Es wird die Wertigkeit dieser Befunde diskutiert.相似文献
109.
J. Wikström D. W. Meyer K. Eickhoff G. Ritter S. Poser H. J. Bauer V. Kratzsch W. R. Kiessling 《Journal of neurology》1977,216(1):47-50
Summary The serological responses of 195 multiple sclerosis (MS) patients and 251 controls were tested against 6/94-parainfluenza virus, which was previously isolated from brain tissue of two patients with MS. The hemagglutination-inhibition titers of 1:128 were found more frequently in MS patients (21.5%) than in controls (14.0%). However, the geometric mean titers did not differ between these two groups. The present study concludes that a causal relationship of 6/94-virus to MS, based on a specific immune response, is improbable, although it does not exclude the possibility of a pathogenetic significance of the agent in the cases from which the autopsy material was derived.Supported by Deutsche Forschungsgemeinschaft (Schwerpunkt Ätiologie und Pathogenese der Multiplen Sklerose und verwandter Erkrankungen) 相似文献
110.
Laboratory of Neurophysiology of Brain Integrative Activity and Section Brain and Behavior,, A. I. Karaev Institute of Physiology, Academy of Sciences of the Azerbaijan SSR, Baku. (Presented by Academician of the Academy of Medical Sciences of the USSR O. S. Adrianov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 111, No. 3, pp. 227–229, March, 1991. 相似文献