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991.
CONTEXT: A characteristic feature of borderline personality disorder (BPD) is self-injurious behavior in conjunction with stress-induced reduction of pain perception. Reduced pain sensitivity has been experimentally confirmed in patients with BPD, but the neural correlates of antinociceptive mechanisms in BPD are unknown. We predicted that heat stimuli in patients with BPD would activate brain areas concerned with cognitive and emotional evaluation of pain. OBJECTIVE: To assess the psychophysical properties and neural correlates of altered pain processing in patients with BPD. DESIGN: Case-control study. SETTING: A university hospital. PARTICIPANTS: Twelve women with BPD and self-injurious behavior and 12 age-matched control subjects. INTERVENTIONS: Psychophysical assessment and blood oxygen level-dependent functional magnetic resonance imaging during heat stimulation with fixed-temperature heat stimuli and individual-temperature stimuli adjusted for equal subjective pain in all the participants. MAIN OUTCOME MEASURE: Blood oxygen level-dependent functional magnetic resonance imaging signal changes during heat pain stimulation. RESULTS: Patients with BPD had higher pain thresholds and smaller overall volumes of activity than controls in response to identical heat stimuli. When the stimulus temperature was individually adjusted for equal subjective pain level, overall volumes of activity were similar, although regional patterns differed significantly. Patient response was greater in the dorsolateral prefrontal cortex and smaller in the posterior parietal cortex. Pain also produced neural deactivation in the perigenual anterior cingulate gyrus and the amygdala in patients with BPD. CONCLUSION: The interaction between increased pain-induced response in the dorsolateral prefrontal cortex and deactivation in the anterior cingulate and the amygdala is associated with an antinociceptive mechanism in patients with BPD.  相似文献   
992.
The primate globus pallidus receives massive innervations from GABAergic striatal neurons that co-release the neuropeptide substance P (SP). To expand our knowledge regarding SP interaction at pallidal level, we used single and double antigen retrieval methods to study the cellular and subcellular localization of SP and its high-affinity receptors neurokinin-1 (NK-1R) and neurokinin-3 (NK-3R) in the globus pallidus of the squirrel monkey (Saimiri sciureus). At the light microscopic level, a large number of neurons and fibers located in both the external (GPe) and internal (GPi) segments of the globus pallidus expressed NK-1R or NK-3R immunoreactivity. At the electron microscopic level, both NK-1R and NK-3R were mainly associated with intracellular sites or located at extrasynaptic positions on the plasma membrane. Presynaptic axon terminals forming symmetric and asymmetric synapses occasionally contained NK-1R and NK-3R. Neurokinin receptors were also observed in a proportion of SP-immunoreactive axon terminals, but these terminals preferentially expressed NK-3R. The pattern of distribution of NK-1R and NK-3R in GPe and GPi indicates that SP effects at pallidal level are mediated through postsynaptic receptor as well as presynaptic autoreceptors and heteroreceptors. These morphological data suggest that, either alone or in conjunction with GABA, SP could have a wide range of effects at pallidal level. This neuroactive peptide may influence in a significant manner the integration and treatment of neural information that flows through the basal ganglia.  相似文献   
993.
CONTEXT: Major depression affects about 25% of patients with Alzheimer's disease (AD) and has serious adverse consequences for patients as well as caregivers. Studies of treatments for depression in AD, like most treatment studies, depend on the ability of the scales used to measure outcome to detect a difference between the effects of treatment and control, particularly in trials conducted over waves. OBJECTIVE: To compare the ability of three depression scales, and some of their subscales, to detect the difference in the effects of drug (treatment) and placebo (control). DESIGN: Comparison of three scales of depression in terms of percent variance explained as indicated by the adjusted or partial eta-squared for the effect of drug versus placebo, controlling for baseline depression, in a randomized, placebo-controlled, parallel, 12-week, clinical trial of sertraline for the treatment of depression with AD. SETTING: University outpatient clinic. PARTICIPANTS: Forty-four patients with probable Alzheimer's disease and Major Depressive Episode. OUTCOME MEASURES: The Cornell Scale for Depression in Dementia (CSDD), the Hamilton Depression Rating Scale (HDRS), and the Neuropsychiatric-Inventory Mood Domains (NPI-M). RESULTS: Examination of the treatment effects as indicated by the partial eta-squared's for each scale at each wave, revealed a slight, but not significant, advantage for the use of the CSDD over the HDRS, and a significant advantage for the use of either of these over the NPI-M. Treatment effects, as reflected in the partial eta-squared's computed for the subscales at each wave, were significant for all four subscales, and were largest for the CSDD 'mood' subscale although they were not significantly greater than for the other subscales. CONCLUSIONS: The CSDD, and particularly its mood subscale, appears to be more sensitive than the HDRS, it's subscales or the NPI-M, for comparing drug to placebo in treating major depression in AD patients. Treatment effects as reflected in the partial eta-squared's were largest on the CSDD mood subscale and increased over time. The pattern for the other subscales was non-monotonic over waves and resembled the pattern for the entire scale. Perhaps combining the CSDD two subscales obscures the treatment effects for the separate subscales.  相似文献   
994.
Papillary tumor of the pineal region (PTPR) is a recently described tumor entity thought to arise from the specialized ependyma of the subcommissural organ. Whereas histologic features of PTPR are well defined, data on the prognostic value of PTPR remain scarce. We therefore investigated clinicopathologic features, including data on progression-free survival and overall survival, in a retrospective series of 31 PTPR. The age of the 14 males and 17 females ranged from 5 to 66 years (median age, 29 years). Histologically, all tumors were characterized by an epithelial-like growth pattern in which the vessels were covered by layers of columnar or cuboidal tumor cells forming perivascular pseudorosettes. Most of the tumor cells showed strong expression of neuron-specific enolase, cytokeratins (particularly CK18), S-100 protein, and vimentin. Most PTPRs examined also expressed microtubule-associated protein-2. Expression of synaptophysin, epithelial membrane antigen, transthyretin, neural cell adhesion molecule, and nestin was encountered in some tumors. Gross total resection could be achieved in 21 of 31 cases; 15 patients received radiotherapy on resection of the primary tumor. Nevertheless, the majority of patients experienced recurrences; 5-year estimates for overall survival and progression-free survival were 73% and 27%, respectively. To conclude, the clinical course of PTPR is characterized by frequent local recurrence, and the value of radiotherapy on disease progression will need to be investigated in future prospective trials.  相似文献   
995.
OBJECTIVE: Defects in glycosylation of alpha-dystroglycan are associated with several forms of muscular dystrophy, often characterized by congenital onset and severe structural brain involvement, collectively known as dystroglycanopathies. Six causative genes have been identified in these disorders including fukutin. Mutations in fukutin cause Fukuyama congenital muscular dystrophy. This is the second most common form of muscular dystrophy in Japan and is invariably associated with mental retardation and structural brain defects. The aim of this study was to determine the genetic defect in two white families with a dystroglycanopathy. METHODS: The six genes responsible for dystroglycanopathies were studied in three children with a severe reduction of alpha-dystroglycan in skeletal muscle. RESULTS: We identified pathogenic fukutin mutations in these two families. Affected children had normal intelligence and brain structure and shared a limb girdle muscular dystrophy (LGMD) phenotype, had marked elevation of serum creatine kinase, and were all ambulant with remarkable steroid responsiveness. INTERPRETATION: Our data suggest that fukutin mutations occur outside Japan and can be associated with much milder phenotypes than Fukuyama congenital muscular dystrophy. These findings significantly expand the spectrum of phenotypes associated with fukutin mutations to include this novel form of limb girdle muscular dystrophy that we propose to name LGMD2L.  相似文献   
996.
BACKGROUND: Saccadic adaptation corrects errors in saccadic amplitude. Experimentally-induced saccadic adaptation provides a method for studying motor learning. The cerebellum is a major participant in saccadic adaptation. Chiari type II malformation (CII) is a developmental deformity of the cerebellum and brainstem that is associated with spina bifida. We investigated the effects of CII on saccadic adaptation. METHOD: We measured eye movements using an infrared eye tracker in 21 subjects with CII (CII group) and 39 typically developing children (control group), aged 8-19 years. Saccadic adaptation was induced experimentally using targets that stepped horizontally 120 to the right and then stepped backward 3 degrees during saccades. RESULTS: Saccadic adaptation was achieved at the end of the adaptation phase in participants in each group. Saccadic amplitude gain decreased by 6.9% in the CII group and 9.3% in the control group. The groups did not differ significantly (p = 0.27). Amplitude gain reduction was significantly less in the CII participants who had multiple shunt revisions. Regression analyses revealed no effects of spinal lesion level, presence of nystagmus, or cerebellar vermis dysmorphology on saccadic adaptation. CONCLUSION: The neural circuits involved in saccadic adaptation appear to be functionally intact in CII.  相似文献   
997.
BACKGROUND: Central periodic breathing (CPB) is common following acute stroke, but its prognostic significance is uncertain. We determined the frequency of CPB on admission with stroke and assessed whether it was related to outcome. METHODS: We measured arterial oxygen saturation (SaO2), chest wall movements and nasal airflow continually with portable monitoring equipment in a large cohort of acute stroke patients, from arrival at hospital through acute assessment to reaching the ward. Baseline neurological examination and 3-month outcome (modified Rankin scale, MRS) were assessed blind to recordings. CPB was defined as cyclical rises and falls in ventilation, with intermittent reduced respiratory airflow or total apnoea. RESULTS: CPB was common in acute stroke (33/138, 24%), but was poorly recognised by clinical staff. Patients with CPB were more likely to have a total anterior circulation syndrome and higher National Institutes of Health Stroke Scale scores than those without (both p<0.01). Patients with CPB had significantly higher median SaO2 than those without (p<0.01), unrelated to whether they received oxygen or not. At 3-month follow-up: 91% of patients with CPB were dead or dependent (MRS>or=3) compared with 53% of those without (OR 8.8; 95% CI 2.5-30.5); the association remained statistically significant after adjusting for covariates (OR 5.9; 95% CI 1.4-25.4). CONCLUSION: CPB is independently associated with poor outcome after stroke, but is not by association with hypoxia. Further work is required to identify causes, effects and interventions that might improve effects of CPB.  相似文献   
998.
Nonmotor symptoms (NMS) of Parkinson's disease (PD) are not well recognized in clinical practice, either in primary or in secondary care, and are frequently missed during routine consultations. There is no single instrument (questionnaire or scale) that enables a comprehensive assessment of the range of NMS in PD both for the identification of problems and for the measurement of outcome. Against this background, a multidisciplinary group of experts, including patient group representatives, has developed an NMS screening questionnaire comprising 30 items. This instrument does not provide an overall score of disability and is not a graded or rating instrument. Instead, it is a screening tool designed to draw attention to the presence of NMS and initiate further investigation. In this article, we present the results from an international pilot study assessing feasibility, validity, and acceptability of a nonmotor questionnaire (NMSQuest). Data from 123 PD patients and 96 controls were analyzed. NMS were highly significantly more prevalent in PD compared to controls (PD NMS, median = 9.0, mean = 9.5 vs. control NMS, median = 5.5, mean = 4.0; Mann-Whitney, Kruskal-Wallis, and t test, P < 0.0001), with PD patients reporting at least 10 different NMS on average per patient. In PD, NMS were highly significantly more prevalent across all disease stages and the number of symptoms correlated significantly with advancing disease and duration of disease. Furthermore, frequently, problems such as diplopia, dribbling, apathy, blues, taste and smell problems were never previously disclosed to the health professionals.  相似文献   
999.
We have characterized in the contusion-lesioned murine spinal cord the behavior of acutely implanted epidermal neural crest stem cells (EPI-NCSC, formerly eNCSC). EPI-NCSC, a novel type of multipotent adult stem cell, are remnants of the embryonic neural crest. They reside in the bulge of hair follicles and have the ability to differentiate into all major neural crest derivatives (Sieber-Blum, M., Grim, M., Hu, Y.F., Szeder, V., 2004. Pluripotent neural crest stem cells in the adult hair follicle. Dev. Dyn. 231, 258-269). Grafted EPI-NCSC survived, integrated, and intermingled with host neurites in the lesioned spinal cord. EPI-NCSC were non-migratory. They did not proliferate and did not form tumors. Significant subsets expressed neuron-specific beta-III tubulin, the GABAergic marker glutamate decarboxylase 67 (GAD67), the oligodendrocyte marker, RIP, or myelin basic protein (MBP). Close physical association of non-neuronal EPI-NCSC with host neurites was observed. Glial fibrillary acidic protein (GFAP) immunofluorescence was not detected. Collectively, our data indicate that intraspinal EPI-NCSC demonstrate several desirable characteristics that may include local neural replacement and re-myelination.  相似文献   
1000.
Increased oxidative stress is implicated in the pathogenesis of diabetic peripheral neuropathy (DPN). However, the efficacy of antioxidant therapy on DPN complicating type 2 diabetes remains unexplored. We therefore determined the ability of the antioxidant taurine to reverse deficits of hind limb sciatic motor and digital sensory nerve conduction velocity (NCV), nerve blood flow (NBF), and sensory thresholds in hyperglycemic Zucker diabetic fatty (ZDF) rats. Experimental groups comprised lean nondiabetic (ND), ND treated with taurine (ND + T), untreated ZDF diabetic (D), and D rats treated with taurine (D + T). Compared to ND rats, 23%, 15% and 56% deficits of motor NCV, sensory NCV and NBF, respectively as well as thermal and mechanical hyperalgesia were reversed by taurine. An 84% deficit of dorsal root ganglion neuron calcitonin gene-related peptide in D rats was prevented by taurine. In summary, the antioxidant taurine reverses neurological and neurovascular deficits in experimental type 2 diabetes.  相似文献   
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