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Immunization with amyloid-β (Aβ) peptide reduces amyloid load in animal studies and in humans; however clinical trials resulted in the development of a pro-inflammatory cellular response to Aβ. Apoptosis has been employed to stimulate humoral and Th2-biased cellular immune responses. Thus, we sought to investigate whether immunization using a DNA vaccine encoding Aβ in conjunction with an attenuated caspase generates therapeutically effective antibodies. Plasmids encoding Aβ and an attenuated caspase were less effective in reducing amyloid pathology than those encoding Aβ alone. Moreover, use of Aβ with an Arctic mutation (E22G) as an immunogen was less effective than wild-type Aβ in terms of improvements in pathology. Low levels of IgG and IgM were generated in response to immunization with a plasmid encoding wild-type Aβ. These antibodies decreased plaque load by as much as 36 ± 8% and insoluble Aβ42 levels by 56 ± 3%. Clearance of Aβ was most effective when antibodies were directed against N-terminal epitopes of Aβ. Moreover, immunization reduced CAA by as much as 69 ± 12% in TgCRND8 mice. Finally, high-molecular-weight oligomers and Aβ trimers were significantly reduced with immunization. Thus, immunization with a plasmid encoding Aβ alone drives an attenuated immune response that is sufficient to clear amyloid pathology in a mouse model of Alzheimer's disease.  相似文献   
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BACKGROUND: Bone marrow cell injection has been introduced to treat patients with ischemic heart disease. However, focal application of bone marrow cells may generate an arrhythmogenic substrate. OBJECTIVES: To assess the electrophysiological and arrhythmogenic effects of intramyocardial bone marrow cell injection in patients with chronic myocardial ischemia. METHODS: Bone marrow was aspirated in 20 patients (65+/-11 years, 19 male) with drug-refractory angina and myocardial ischemia. Electroanatomical mapping (NOGA, Biosense-Webster, Waterloo, Belgium) was performed during mononuclear cell isolation. Areas for cell injection were selected based on the localization of ischemia on SPECT. These areas were mapped in detail to evaluate local bipolar electrogram duration, amplitude and fragmentation. Mononuclear cells were injected in the ischemic area with the NOGA system. SPECT and electroanatomical mapping were repeated at 3 months. Holter monitoring was repeated at 3 and 6 months. RESULTS: SPECT revealed a decrease in the number of segments with ischemia (3.5+/-2.5 vs. 1.1+/-1.0 at 3 months; P<0.01) and an increased left ventricular ejection fraction (44+/-13% vs. 49+/-17% at 3 months; P=0.02). The number of ventricular premature beats remained unchanged (10+/-24x10(2)/24h vs. 8+/-23x10(2)/24h at 3 months (P=NS) and 12+/-30x10(2)/24h at 6 months (P=NS)). At 3 months follow-up, bone marrow cell injection did not prolong electrogram duration (15.9+/-4.6 ms vs. 15.6+/-4.0 ms; P=NS), decrease electrogram amplitude (3.8+/-1.5 mV vs. 3.8+/-1.5 mV; P=NS), or increase fragmentation (2.0+/-0.5 vs. 1.9+/-0.4; P=NS). CONCLUSION: Intramyocardial bone marrow cell injection does not increase the incidence of ventricular arrhythmias and does not alter the electrophysiological properties of the injected myocardium.  相似文献   
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Two cases of internal herniation through a defect in the broad ligament of the uterus are described. Both were successfully treated laparoscopically. This rare condition should be borne in mind when a middle-aged woman presents with colicky lower abdominal pain. The cause is unknown, but both congenital and acquired origins have been proposed. As far as emergency situations are concerned, laparoscopy has proven to be both a diagnostic and a therapeutic tool.  相似文献   
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OBJECTIVES: Local anaesthetic infiltration into the carotid sinus during carotid endarterectomy (CEA) has been recommended to minimise blood pressure fluctuations but its use remains controversial. The aim of this meta-analysis was to determine whether intra-operative administration of local anaesthetic reduces the incidence of haemodynamic instability following CEA. MATERIALS AND METHODS: A search of the Medline, Pubmed and Embase databases and the Current Controlled Trials register identified four trials, which met the pre-defined inclusion criteria for data extraction. Pooled odds ratios with 95 per cent confidence intervals (c.i.) for the development of post-operative hypotension and hypertension were calculated using a random-effects model. RESULTS: Outcomes of 432 patients were studied. Local anaesthetic blockade of the carotid sinus was associated with a pooled odds ratio of 1.25 (95 per cent c.i. 0.496 to 3.15); p=0.216) and 1.28 (95 per cent c.i. 0.699 to 2.33; p=0.428) for the development of post-operative hypotension and hypertension respectively. Although none reach significance there was a trend towards increased risk of developing a complication in those patients who received local anaesthetic. CONCLUSIONS: There are insufficient data to determine the role of intra-operative local anaesthetic administration in reducing post-operative blood pressure lability following CEA. Conversely, the possibility of harm cannot be excluded on the basis of the currently available data.  相似文献   
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