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991.
992.
We report a rare case of thoracic intramedullary schwannoma. The patient, a 37-year-old woman, showed no evidence of neurofibromatosis. The possible etiology and treatment of the tumor are discussed and a review of literature is presented. 相似文献
993.
Mazur-Kolecka B Frackowiak J Krzeslowska J Ramakrishna N Haske T Emmerling MR Zhang W Kim KS Wisniewski HM 《Journal of neuropathology and experimental neurology》1999,58(3):288-295
Canine smooth muscle cells (SMCs), cultured from amyloid-affected brain blood vessels accumulate Alzheimer amyloid-beta peptide (Abeta) intracellularly, either spontaneously or after treatment with apolipoprotein E (apoE). ApoE is codeposited with Abeta, which suggests that apoE participates in Abeta accumulation. We tested the hypothesis that apoE-induced accumulation of Abeta in SMCs is caused by an increased production of amyloid-beta precursor protein (AbetaPP) and/or its altered metabolism. We found that 24 hours of treatment with apoE3 or apoE4 induced intracellular accumulation of Abeta-immunoreactive deposits in SMCs but did not influence AbetaPP production and processing. The treatment with apoE3 or E4 for 3 days resulted in the following: increased Abeta-accumulation; reduced levels of secreted Abeta; increased production and cellular retention of mature AbetaPP770; and reduced culture growth, cell proliferation, and viability. ApoE4, but not apoE3, increased cellular levels of mRNA AbetaPP 770 (the main form produced in SMCs) about ninefold. ApoE3 stimulated production and cellular retention of endogenous apoE. We hypothesize that Abeta accumulation is triggered by apoE, which may bind and immobilize soluble Abeta produced in SMCs. The newly formed Abeta deposits may further accelerate Abeta accumulation by altering metabolism of AbetaPP. 相似文献
994.
Ipsilesional neglect: behavioural and anatomical features 总被引:2,自引:0,他引:2
M Kim D Na G Kim J Adair K Lee K Heilman 《Journal of neurology, neurosurgery, and psychiatry》1999,67(1):35-38
OBJECTIVE: To learn more about the behavioural and anatomical features of ipsilesional neglect. METHODS: Thirty consecutive patients with spatial neglect were tested on cancellation and line bisection tasks. To learn if patients with ipsilesional neglect demonstrate the sensory-attentional or motor-intentional type of neglect, a video apparatus was used that dissociates these determinants. RESULTS: Five patients showed evidence of ipsilesional neglect. This phenomenon was seen only on the line bisection task. All patients with ipsilesional neglect had lesions involving frontal-subcortical regions. Although ipsilesional neglect evolved from early in three of five cases, the other patients displayed ipsilesional neglect without initial contralateral neglect, suggesting that ipsilesional neglect cannot be fully attributed to a compensatory strategy. The results of the tests that used the video apparatus indicate that right sided frontal or subcortical injury may induce contralateral attentional or intentional "approach" behaviours. CONCLUSIONS: Ipsilesional neglect is most often associated with frontal-subcortical lesions, cannot be entirely attributed to a compensatory strategy, and may be induced by an attentional bias, an intentional bias, or both. 相似文献
995.
Our previous studies have demonstrated that supraspinal GABAergic receptors are differentially involved in the antinociception induced by morphine and beta-endorphin given intracerebroventricularly (i.c.v.) in the tail-flick and hot-plate tests. These two models employed a phasic, thermal nociceptive stimulus. The present study was designed to examine the possible involvement of supraspinal GABAergic receptors in opioid-induced antinociception in the formalin test. Morphine (1 microg) and beta-endorphin (1 microg) given i.c.v. displayed the almost complete inhibitory effects against the hyperalgesic response in both phases. Muscimol (75-100 ng) and baclofen (5-10 ng) injected i.c.v. produced the hypoalgesic response in the both phases. The hypoalgesic response induced by muscimol and baclofen observed during the second phase was more pronounced than that observed during the second phase. Baclofen (2.5 ng), at the dose which did not affect the hyperalgesic response, resulted in a significant reversal of the i.c.v. administered beta-endorphin-induced hypoalgesic response observed during the second, but not the first, phase. However, the hypoalgesic response induced by i.c.v. administered morphine was not changed by the same dose of muscimol or baclofen injected i.c.v. Our results indicate that, at the supraspinal level, GABA(B)receptors appear to be involved in the modulation of antinociception induced by supraspinally administered beta-endorphin, but not morphine, in the formalin test model. 相似文献
996.
Studies concluding that St. John's wort (Hypericum perforatum) is an effective antidepressant can be challenged due to questionable methodology. We attempt to correct this by a meta-analysis utilizing only well-defined clinical trials. Controlled, double-blind studies using strictly defined depression criteria were analyzed by the rate of change of depression and by the number of "treatment responders." Rates of side effects and dropouts were also analyzed. Hypericum was 1.5 times more likely to result in an antidepressant response than placebo and was equivalent to tricyclic antidepressants (TCAs). The meta-analysis also showed that there was a higher dropout rate in the TCA group and that the TCAs were nearly twice as likely to cause side effects, including those more severe than hypericum. Hypericum perforatum was more effective than placebo and similar in effectiveness to low-dose TCAs in the short-term treatment of mild to moderately severe depression. However, design problems in existing studies prevent definitively concluding that St. John's wort is an effective antidepressant. 相似文献
997.
Kim SH Manes F Kosier T Baruah S Robinson RG 《The Journal of nervous and mental disease》1999,187(6):327-335
This study was undertaken to identify the clinical and pathoanatomical correlates of irritability in patients with closed head injuries. A consecutive series of 66 patients was assessed in hospital and at 3, 6, 9, and 12-month follow-ups. Patients fulfilling criteria for irritability were divided into 2 groups based on the immediate or delayed onset of their irritability and compared with patients without irritability for background characteristics, impairment variables, and lesion characteristics. There were 12 patients (18.2%) with acute onset irritability and 10 (15.1%) with delayed onset irritability. Acute onset irritability patients had a higher frequency of left cortical lesions. Delayed onset irritability patients showed a strong association with poor social functioning and greater impairment in activities of daily living. The findings suggest that post-brain injury irritability may have different causes and treatment in the acute and chronic stages. 相似文献
998.
CD18-mediated neutrophil recruitment contributes to the pathogenesis of reperfused but not nonreperfused stroke 总被引:36,自引:0,他引:36
Prestigiacomo CJ Kim SC Connolly ES Liao H Yan SF Pinsky DJ 《Stroke; a journal of cerebral circulation》1999,30(5):1110-1117
BACKGROUND AND PURPOSE: Neutrophil (PMN) recruitment mediated by increased expression of intercellular adhesion molecule-1 expression (ICAM-1, CD54) in the cerebral microvasculature contributes to the pathogenesis of tissue injury in stroke. However, studies using blocking antibodies against the common beta2-integrin subunit on the PMN, the counterligand for ICAM-1 (CD18), have demonstrated equivocal efficacy. The current study tested the hypothesis that mice deficient in CD18 would be protected in the setting of reperfused but not nonreperfused stroke. METHODS: Two groups of mice were studied, those whose PMNs could express CD18 (CD18 +/+) and those mice hypomorphic for the CD-18 gene (CD18 -/-). PMNs obtained from CD18 -/- or CD18 +/+ mice were fluorescently labeled and tested for binding to murine brain endothelial monolayers. Using a murine model of focal cerebral ischemia in which an occluding suture placed in the middle cerebral artery (MCA) is removed after 45 minutes (transient ischemia, reperfused stroke) or left in place (permanent ischemia, nonreperfused stroke), cerebral infarct volumes (% ipsilateral hemisphere by TTC staining), cerebral blood flow (CBF, % contralateral hemisphere by laser-Doppler flowmetry), and survival (%) were examined 24 hours after the initial ischemic event. Adoptive transfer studies used 111In-labeled PMNs (from either CD18 +/+ or CD18 -/- mice) to examine the relative accumulation of PMNs in the ischemic region. RESULTS: PMNs obtained from CD18 -/- mice exhibit reduced adhesivity (compared with CD18 +/+ PMNs) for both quiescent and cytokine-activated endothelial monolayers. CD18 -/- mice (n=14) subjected to transient focal cerebral ischemia demonstrated a 53% decrease in infarct volumes versus CD18 +/+ mice (n=26, P<0.05), improved penumbral CBF at 24 hours (1.8-fold, P=0.02), and a 3.7-fold decrease in mortality (P=0.02). However, when CD18 -/- mice (n=12) were subjected to permanent focal cerebral ischemia, no differences were noted in infarct volume, mortality, or CBF versus similarly treated CD18 +/+ mice (n=10). There was a greater accumulation of CD18 +/+ PMNs in the ischemic zone of CD18 +/+ animals than CD18 -/- animals subjected to reperfused stroke (82% increase, P=0.02), although there was no difference between groups when subjected to permanent MCA occlusion. CONCLUSIONS: Deficiency for the CD18 gene confers cerebral protection in a murine model of reperfused stroke, but this benefit does not extend to CD18-deficient animals subjected to permanent MCA occlusion. These data suggest that anti-PMN strategies should be targeted to reperfused stroke and may perhaps be used in conjunction with thrombolytic therapy that establishes reperfusion. 相似文献
999.
In a previous study, we reported increased NOS expression in the astrocytes in the spinal cord of SOD mutant transgenic mice that are used as ALS animal model. Recently, Messmer and Brune suggested that nitric oxide-induced apoptosis is intimately related with p53-dependent signaling pathway, and de la Monte et al. reported increased p53-immunoreactivity in the spinal cord of ALS patients. In the present study, we performed immunocytochemical studies to investigate the changes of p53-immunoreactivity in the brains of the mutant transgenic mice expressing a human Cu/Zn SOD mutation. Immunocytochemistry showed intensely stained p53-IR glial cells with the appearance of astrocytes in all levels of the spinal cord of the mutant transgenic mice, but no p53-IR glial cells were observed in the spinal cord of the control mice. P53-IR astrocytes were also detected in the brain stem of the mutant transgenic mice. In the medulla, they were observed in the medullary reticular formation, hypoglossal nucleus, vestibular nucleus, dorsal motor nucleus of the vagus and nucleus ambiguus. In the pons, their presences were noted in the pontine reticular formation, and trigeminal and facial nuclei. In the midbrain, astrocytes were detected in the mesencephalic reticular formation, red nucleus and periaqueductal gray matter. In the cerebellum, intensely stained p53-IR astrocytes were detected in the intracerebellar nuclei. In contrast to the mutant transgenic mice, no p53-IR astrocytes were detected in the brain stem and spinal cord of the control mice. Further multidisciplinary investigations involving p53-mediated cellular damage and pathogenesis of ALS are needed to clarify the importance of these results. 相似文献
1000.
Estriol ameliorates autoimmune demyelinating disease: implications for multiple sclerosis 总被引:9,自引:0,他引:9
OBJECTIVE: To evaluate the use of estriol in the treatment of experimental autoimmune encephalomyelitis (EAE) and other cell mediated autoimmune diseases. BACKGROUND: Experimental autoimmune encephalomyelitis is a T helper 1 (Th1)-mediated autoimmune demyelinating disease that is a useful model for the study of immune responses in MS. Interestingly, both EAE and MS have been shown to be ameliorated during late pregnancy. METHODS: Estriol, progesterone, and placebo pellets were implanted in mice during the effector phase of adoptive EAE. Disease scores were compared between treatment groups, and autoantigen-specific humoral and cellular responses were examined. RESULTS: Estriol treatment reduced the severity of EAE significantly compared with placebo treatment whereas progesterone treatment had no effect. Estriol doses that induced serum estriol levels that approximated estriol levels during late pregnancy were capable of ameliorating disease. Estriol-treated EAE mice had significantly higher levels of serum antibodies of the immunoglobulin (Ig) G1 isotype specific for the autoantigen myelin basic protein (MBP). Further, MBP-specific T-lymphocyte responses from estriol-treated EAE mice were characterized by significantly increased production of the Th2 cytokine interleukin 10 (IL-10). T lymphocytes were shown to be the primary source of IL-10 within antigen-stimulated splenocyte populations. CONCLUSIONS: Estriol as a hormone involved in immune changes during pregnancy may provide a basis for the novel therapeutic use of estriol for MS and other putative Th1-mediated autoimmune diseases that improve during late pregnancy. 相似文献