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1.
This article describes the association between previous infection and/or vaccination and the development of optic neuritis (ON) in 18 children. Ten of these children subsequently developed clinically definite multiple sclerosis (MS), while in 8 patients a clinically definite etiology could not be confirmed. Vaccination preceded the first ON attack in 6 patients, all but one of whom subsequently developed MS. It also preceded subsequent demyelinating events in 6 patients. Ten of the patients had a bacterial or viral infection within the 2 weeks prior to the first symptoms of ON. Intrathecal antibody synthesis against 2 or more viruses could be shown in 5 out of 8 patients studied; 5 out of 6 patients had oligoclonal antibodies in CSF and 12 out of 16 patients a high IgG index. Neither intrathecal antibody synthesis against 2 or more viruses nor elevated IgG indexes could be found in the control patients. Measles and mumps occurred at a significantly later age in the children who subsequently developed MS than in the control children, and these patients had significantly more events that might have impaired the blood-brain barrier than the controls. These results indicate that immunological events leading to MS may be triggered during childhood. Vaccination and infection often precede ON in childhood. Intrathecal viral antibody production can occur already in childhood at the time of the first symptoms of MS.  相似文献   
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Ten patients with childhood optic neuritis (5 with a single attack of ON and 5 with later MS) were studied at various stages of the disease. Lymphocyte count and function were analysed in the peripheral blood of all patients, 3 repeatedly, and in one they were also analysed in the CSF. T-lymphocytes counts were normal in all but 2 MS cases who had high counts. In acute stages the T4/T8 ratio were high in 1/3 determinations, in recovery low in 2/2 determinations, and in stable stages normal in 6/8 determinations. Lymphocyte function, measured by PHA, ConA and PWM stimulation, was normal in all but one. One patient showed significantly higher T-cell percentages and a high number of stimulated lymphocytes in CSF but a lower count of suppressor cells than in the blood. We found no abnormalities specific to MS nor to childhood MS or to disease activity stage. Rather than peripheral blood, it would seem more worthwhile to study CSF to clarify the pathogenesis of ON and MS.  相似文献   
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A series of positron emission tomography scans was made on two monkeys during a 16-month period when they received manganese(IV)oxide by subcutaneous injection. The distribution of [11C]-nomifensine uptake, indicating dopamine terminals, was followed in both monkey brains. The brain distributions of [11C]-raclopride, demonstrating D2 dopamine receptors, and [11C]-l-dopa, as a marker of dopamine turnover, were followed in one monkey each. The monkeys developed signs of poisoning namely unsteady gait and hypoactivity. The [11C]-nomifensine uptake in the striatum was reduced with time and reached a 60% reduction after 16 months exposure. This supports the suggestion that dopaminergic nerve endings degenerate during manganese intoxication. The [11C]-l-dopa decarboxylation was not significantly altered indicating a sparing of [11C]-l-dopa decarboxylation during manganese poisoning. A transient decrease of [11C]-raclopride binding occurred but at the end of the study D2-receptor binding had returned to starting values. The magnetic resonance imaging (MRI) revealed that the manganese accumulated in the globus pallidus, putamen and caudate nucleus. There were also suggestions of gliosis/edema in the posterior limb of the internal capsule. MRI might be useful to follow manganese intoxication in humans as long as the scan is made within a few months of exposure to manganese, i. e. before a reversal of the manganese accumulation.  相似文献   
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Serum levels of 8 steroids and urinary cortisol excretion were determined in 10 infants before and during corticotropin therapy for infantile spasms. High serum dehydroepiandrosterone-androstenedione concentration ratio distinguished the 6 infants with good therapeutic response from the 4 with poor response (p = 0.001). No such distinction was obtained directly by any of the serum steroid levels, 24-hour urinary cortisol, or serum pregnenolone-progesterone concentration ratio. This suggests that the therapeutic effect of corticotropin may be mediated by steroid factors other than cortisol. Inhibition of the 3 beta-hydroxysteroid dehydrogenase system in zona reticularis might be beneficial during the corticotropin therapy.  相似文献   
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Riikonen R  Somer M  Turpeinen U 《Epilepsia》1999,40(11):1642-1648
PURPOSE: In patients with progressive encephalopathy, hypsarrhythmia, and optic atrophy (PEHO) syndrome, the pathophysiology underlying early progressive cerebellar and brainstem degeneration and severe epilepsy is unknown. Because insulin-like growth factor (IGF)-1 has been shown significantly to promote survival of cerebellar neurons, we wanted to see if the IGF system played a role in the pathogenesis of cerebellar atrophy. METHODS: We used a sensitive enzyme immunoassay kit for measuring cerebrospinal fluid (CSF) IGF-1 and insulin-like growth-binding protein (IGFBP)-3 in four groups of patients: PEHO syndrome patients (eight), PEHO-like patients (seven), age-matched controls (31), and patients with other types of cerebellar atrophy (11). RESULTS: Patients with PEHO syndrome and those with other progressive, degenerative cerebellar diseases had lower levels of CSF IGF-1 than the controls with other neurologic diseases. The CSF IGF-1 also allowed us to differentiate the "true" PEHO patients from the "PEHO-like" patients (those with similar clinical symptoms but without the typical neuroophthalmologic or neuroradiologic findings). The concentrations of IGFBP-3 did not significantly differ in any of the patient or control groups studied. CONCLUSIONS: CSF IGF-1 levels might be used as a marker of the degeneration of neurons in specific areas.  相似文献   
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During 1996 and 1997 a panel of European haematologists, oncologists, and neonatologists developed specific paediatric guidelines for the use of colony stimulating factors based on published literature and the clinical experience of these specialists within each of 13 countries. Well established indications for use comprise intervention in patients with life-threatening infection, adjunctive therapy post autologous bone marrow transplantation (BMT), mobilization of peripheral blood progenitor cells for autologous BMT, patients with acquired aplastic anaemia on anti-lymphocyte globulin and cyclosporin regimen, and severe congenital neutropenia. Less clear indications include primary prophylaxis to support dose intensification in children with high risk/advanced malignancies, secondary prophylaxis to prevent neutropenia in patients with a history of severe neutropenia, support therapy in cases of poor marrow function following BMT and for deteriorating marrow function following successful BMT, in neonatal sepsis and non infectious neonatal neutropenia, in drug induced neutropenia and in HIV-positive patients. Treatment is generally well tolerated and granulocyte colony stimulating factor appears better tolerated than granulocyte and macrophage colony stimulating factor. Economically colony stimulating factors have not been shown to induce excessive costs for a given patient. Conclusion In general the adult guidelines are applicable to children but additional considerations (aggressive or very progressive childhood neoplasms, specific indications, neonatal use, congenital disorders) must be taken into account. Received: 21 October 1997 and in revised form: 30 April 1998 /Accepted: 5 May 1998  相似文献   
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OBJECTIVE: We assessed the risk of prostate cancer by exposure to Chlamydia trachomatis. METHOD: Seven hundred thirty eight cases of prostate cancer and 2,271 matched controls were identified from three serum sample banks in Finland, Norway, and Sweden by linkage to the population based cancer registries. RESULTS: A statistically significant inverse association (odds ratio, 0.69; 95% confidence interval, 0.51-0.94) was found. It was consistent by different serotypes and there was a consistent dose-response relationship. CONCLUSION: C. trachomatis infection is not likely to increase the risk of prostate cancer. Whether the inverse relationship is true or due to difficulties in measuring the true exposure in prostatic tissue by serology, confounders or other sources of error remain open.  相似文献   
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