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Depression is a feature of both Lewy body disorders and multiple system atrophy (MSA). Since serotonergic neurons of the rostral raphe have been implicated in depression, we sought to determine whether there is a differential involvement of these neurons in cases with clinically diagnosed dementia with Lewy bodies (DLB) or MSA. We studied the brainstem obtained at autopsy from fourteen patients with diagnosis of DLB and pathological limbic or neocortical stage Lewy body disease, 13 patients with clinical and neuropathological diagnosis of MSA, and 12 controls with no history of neurologic disease. The clinical features of these patients were analyzed retrospectively by reviewing their medical records. Serial sections were immunostained for tryptophan hydroxylase (TrOH) and α-synuclein and cell counts were performed in the dorsal raphe (DR), median raphe (MR) and medullary raphe nuclei. There was loss of serotonergic cells in both the DR and MR in DLB compared to control cases: For the DR, the number of cells/section were 53 ± 6 in DLB versus 159 ± 13 (P < 0.001) respectively, and for the MR 70 ± 11 in DLB versus 173 ± 23 (P < 0.001) respectively. In contrast, these cells were relatively preserved in MSA. The caudal raphe groups were affected both in MSA and in DLB. There is a differential involvement of raphe neurons in DLB and MSA. Although loss of rostral raphe neurons may contribute to depression in DLB, this appears to be less likely in MSA. Factors other than the neurochemical phenotype determine neuronal vulnerability in MSA.  相似文献   
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Background – Orthostatic hypotension (OH) is a rare manifestation of medulla oblongata lesions that may be because of interruption of descending sympathoexcitatory axons. Aims – To illustrate the location of a medullary lesion that produced OH following resection in relationship to the location of putative sympathoexcitatory pathways. Method – A case with dorsal medullary cavernous angioma presenting with OH is described. The possible localization of lesion was compared with distribution of tyrosine hydroxylase (TH)‐immunoreactive axons in a comparable section of the medulla of a control brain. Results – The patient had marked OH after partial removal of the cavernous angioma. Biopsy confirmed the diagnosis. The magnetic resonance imaging location of the lesion overlapped that of TH‐immunoreactive axons of the medullary transtegmental tract. Conclusions – A restricted lesion of medullary lesion interrupting the catecholaminergic transtegmental tract arising from the sympathoexcitatory C1 neurons of the rostral ventrolateral medulla could result in severe OH.  相似文献   
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AIM: This study explored the contribution of two psychosocial factors, locus of control (LOC) and perceived parenting style, to symptoms of internalizing disorders in children with Tourette syndrome (TS). This contribution was further evaluated in relation to TS severity. METHODS: Sixty-five children (53 boys, 12 girls) ages 9.0-16.9 years, of normal intelligence, completed questionnaires evaluating their depression and anxiety symptoms, LOC, and maternal parenting style. Their mothers rated TS severity, determined by tic severity, symptoms of attention-deficit hypreactivity disorder (ADHD) and obsessive compulsive symptoms (OCS). RESULTS: Higher rates of symptoms of anxiety and depression were associated with a more external LOC and a more rejecting and controlling parenting style. Additionally, depression correlated significantly with tic severity, ADHD and OCS, whereas anxiety correlated only with ADHD symptoms and OCS, but not with tics. Regression analyses showed that LOC, OCS and ADHD symptoms each significantly contributed to predicting anxiety level, whereas LOC and ADHD symptoms significantly contributed to predicting depression symptoms. CONCLUSIONS: Rates of symptoms of anxiety and depression in children with TS are markedly influenced by psychosocial factors, extending beyond the influence of ADHD and OCD, both common comorbid disorders in TS. An internal LOC, which is associated with an accepting and autonomy-granting parenting style, appears to be a protective factor against anxiety and depression.  相似文献   
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Background: Electrical stimulation (ES) of the stomach has been shown to modulate LESP. Electrical stimulation, using neural high frequency stimulation (NGES) can induce contractions of the smooth muscle of the gut. The purpose of this study was to determine if electrical stimulation of the LES can affect LESP. Methods: Four female hound dogs, weight: 20–25 kg, underwent an esophagostomy that allowed the introduction of a sleeve manometry catheter into the esophagus. They were also implanted with a pair of electrodes along the longitudinal axis of the LES. After 3 weeks of recovery, they underwent esophageal manometry recording during control and ES, performed randomly on separate days, using 4 different stimulations: 1‐Low frequency: freq: 6 cycles/min, pulse: 350 milisec, amp: 5 mAmp; 2 High‐frequency: freq: 50 Hz, pulse: 1 milisec, amp: 5 mAmp; 3‐ NGES: freq: 50 Hz, pulse:20 milisec, amp:10 volts; 4‐ High‐frequency, circular: freq: 20 Hz, pulse:1 milisec, amp:5 mAmp. All recordings were performed 1 hour after consumption of 3 ounces of canned dog food, to prevent fluctuations in LESP and under mild sedation (acepromazine 0.5 mg kg­1). Tests consisted, during ES days, of 3 periods of 20 minutes each: control , stimulation and post stimulation. The effect of NGES was also tested under anesthesia and following administration of L‐NAME 50 mg kg­1 IV. and also atropine 0.05 mg kg­1 IV. Analysis: area under the curve (AUC) and pressure were compared among the 3 periods. Data shown as mean ± SD, ANOVA and t‐test, p < 0.05. Results: Sustained increase in LESP was observed during low frequency stimulation, 32.1 ± 12.8 vs. 42.4 ± 18.0 vs. 50.1 ± 23.6, control vs. stimulation vs. post stimulation respectively, p = 0.013. AUC also significantly increased during and after stimulation, 39,320.3 ± 15,722 vs. 51,294 ± 21,826 vs. 59,823.6 ± 28,198.4 mmHgxsec, control vs. stimulation vs. post stimulation respectively, p = 0.01. There was no significant change with other types of ES. NGES induced an initial rise in LESP followed within few seconds by relaxation with slow resumption of pressure over a 1 minute period. L‐NAME increased LESP and augmented the initial rise in LESP following NGES but markedly diminished or abolished the relaxation phase. Atropine lowered LESP and abolished the initial rise in LESP induced by NGES. Conclusions: Low frequency ES of the LES increases LESP in conscious dogs. NGES has dual effect on LESP: an initial stimulation, cholinergically mediated, followed by relaxation mediated by nitric oxide.  相似文献   
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ObjectiveTo determine the knowledge of HIV/AIDS among primary school pupils in north central area of Nigeria.Methods2000 randomly selected primary school pupils in and around eastern part of Idoma area of Benue state were interviewed using an open-ended questionnaire. Data analysis was done with EPI-INFO 2000. The Chi-square test was used for statistical analysis and the 0.05 level of significance was adopted.ResultsA totle of 1010 males and 990 females at ages between five and sixteen years were drawn from 10 primary schools in the area. Pupils in the higher classes were more knowledgeable and sex difference was not statistically significant. Certain misconceptions were noted.ConclusionsThere is need for health education for all cadres of primary school pupils in the area, which will increase the awareness of the disease.  相似文献   
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