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Interleukin (IL)‐6 is crucial for the induction of many murine models of autoimmunity including experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. While IL‐6‐deficient mice (IL‐6 KO) are resistant to EAE, we showed previously that in transgenic mice with astrocyte‐targeted production of IL‐6‐restricted to the cerebellum (GFAP‐IL6), EAE induced with MOG35–55 was redirected away from the spinal cord to the cerebellum. To further establish the importance of IL‐6 produced in the central nervous system, we have generated mice producing IL‐6 essentially only in the brain by crossing the GFAP‐IL6 mice with IL‐6 KO mice. Interestingly, GFAP‐IL6‐IL‐6 KO mice showed a milder but almost identical phenotype as the GFAP‐IL6 mice, which correlated with a lower load of inflammatory cells and decreased microglial reactivity. These results indicate that not only is cerebellar IL‐6 production and eventual leakage into the peripheral compartment the dominating factor controlling this type of EAE but that it can also facilitate induction of autoimmunity in the absence of normal systemic IL‐6 production. © 2013 Wiley Periodicals, Inc.  相似文献   
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BACKGROUND: An association between midlife blood pressure levels and late-life cognitive impairment has been reported. Hypertension is one of the most important factors related to the presence of cerebral white matter lesions, which is a prognostic factor for the development of cognitive impairment. Studies have shown a relationship between white matter lesions and cognitive decline in elderly hypertensive patients. The aim of the present study was to evaluate cognitive function in asymptomatic middle-aged hypertensive patients according to the presence or absence of white matter lesions. METHODS: Sixty never-treated essential hypertensive patients (38 men, 22 women), aged 50 to 60 years (mean age, 54.4 +/- 3.8 years), without clinical evidence of target organ damage, were studied. All patients underwent brain magnetic resonance imaging to establish the presence or absence of white matter lesions, using the Rotterdam criteria. Cognitive function was evaluated by a neuropsychologic test battery measuring attention, memory, intelligence, anxiety, and depression. RESULTS: Twenty-three hypertensive patients (38%) were found to have white matter lesions on brain resonance. These patients exhibited a significantly worse performance on digit span forward, a standardized measure of attention than hypertensives without white matter lesions (4.86 +/- 1.14 v 5.51 +/- 0.97; P =.027). Hypertensive patients with white matter lesions showed no differences on both visual and logical memory tests when compared with patients without lesions. CONCLUSIONS: We conclude that the presence of silent cerebral white matter lesions in middle-aged hypertensive patients is associated with a mild decline in basic attention.  相似文献   
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OBJECTIVE : Age, hypertension, diabetes mellitus and a history of cardiovascular disease are the most important factors related to the presence of cerebral white matter lesions (WML), which are a common finding in elderly people. This study investigates which factors related to hypertension per se are associated with the presence of WML in asymptomatic, middle-aged, never-treated essential hypertensive patients. METHODS : A total of 66 untreated essential hypertensive patients of both genders, aged 50-60 years, with neither diabetes mellitus nor evidence of cardiovascular disease, were studied. Hypertensive patients were classified into two groups according to the presence or absence of WML in brain magnetic resonance imaging (MRI). RESULTS : A total of 39 (59.1%) hypertensives showed no WML in brain MRI, and 27 (40.9%) exhibited the presence of WML. Compared with hypertensives without WML, patients with WML showed significantly higher values of both office and 24 h ambulatory blood pressure monitoring (ABPM) systolic, diastolic, mean and pulse pressure. No differences were observed in either the nocturnal fall of blood pressure, or in blood pressure variability, assessed by 24 h standard deviation, among hypertensives with WML. In contrast, the nocturnal decline of heart rate was significantly blunted in patients with WML, compared with those without WML. CONCLUSIONS : Cerebral white matter lesions are a common finding in asymptomatic middle-aged essential hypertensives. The severity of blood pressure elevation seems to be the most important factor related to the presence of WML. Neither the circadian rhythm nor the long-term variability of blood pressure were related to WML.  相似文献   
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We present a 29-year-old woman with a long history of attacks of migraine with and without visual aura. She was a heavy smoker (20 cigarettes/d) and was currently taking oral contraceptives. During a typical migraine attack with aura, she developed dysarthria, left brachial hemiparesis and hemihypoesthesia and brief and autolimited left clonic facial movements. Four hours after onset, vascular headache and focal sensorimotor neurological deficit were the only persisting symptoms and, on seventh day, she was completely recovered. Brain magnetic resonance imaging on day 20 after onset showed a subacute ischemic lesion in the right temporo-parietal cortex compatible with cortical laminar necrosis (CLN). Extensive neurological work-up done to rule out other known causes of cerebral infarct with CLN was unrevealing. Only ten of 3.808 consecutive stroke patients included in our stroke registry over a 19-year period fulfilled the strictly defined International Headache Society criteria for migrainous stroke. The present case is the unique one in our stroke registry that presents CLN related to migrainous cerebral infarction. Migrainous infarction can result in CLN.  相似文献   
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We evaluated the presence of various Beta-lactamase genes within the bacteriophages in sewage. Results showed the occurrence of phage particles carrying sequences of bla(OXA-2), bla(PSE-1) or bla(PSE-4) and bla(PSE)-type genes. Phages may contribute to the spread of some Beta-lactamase genes.  相似文献   
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Purpose Patients with colorectal cancer have a high risk of developing metachronous neoplasms. Identification of predictive factors associated with such conditions would allow individualized follow-up strategies in these patients. This study was designed to identify individual and familial factors associated with the development of metachronous colorectal neoplasms in patients with colorectal cancer. Methods In the context of a prospective, multicenter, general population-based study—the EPICOLON project—all patients with colorectal cancer attended in ten Spanish hospitals during a one-year period were included. Patients with familial adenomatous polyposis or inflammatory bowel disease were excluded. All patients were monitored by colonoscopy within two years of the diagnoses. Demographic, clinical, pathologic, molecular (microsatellite instability status and immunohistochemistry for MSH2 and MLH1), and familial characteristics (fulfillment of Amsterdam I or II criteria, and revised Bethesda guidelines) were analyzed. Results A total of 353 patients were included in the study. At two years of follow-up, colonoscopy revealed the presence of adenomas in 89 (25 percent) patients and colorectal cancer in 14 (3.9 percent) patients, in 7 cases restricted to anastomosis. Univariate analysis demonstrated that development of metachronous neoplasm (adenoma or colorectal cancer) was associated with personal history of previous colorectal cancer (odds ratio, 5.58; 95 percent confidence interval, 1.01–31.01), and presence of previous or synchronous adenomas (odds ratio, 1.77; 95 percent confidence interval, 1.21–3.17). Although nonstatistical significance was achieved, metachronisms were associated with gender (P < 0.09) and differentiation degree (P < 0.08). Multivariate analysis identified previous or synchronous adenomas (odds ratio, 1.98; 95 percent confidence interval, 1.16–3.38) as independent predictive factor. Neither presence of tumor DNA microsatellite instability nor family history correlated with the presence of metachronous neoplasms. Conclusions Patients with previous or synchronous colorectal adenoma have an increased risk of developing metachronous colorectal neoplasms. Accordingly, this subgroup of patients may benefit from specific surveillance strategies. Supported by grants from the Red Nacional de Investigación en Hepatología y Gastroenterología (Instituto de Salud Carlos III, C03/02) and from Fondo de Investigaciones Sanitarias (FIS PI061384). Xavier Llor is a recipient of a Ramon y Cajal grant form Ministerio de Ciencia y Tecnología of the Spanish government Presented at the meeting of the United European Gastroenterology, Copenhagen, Denmark, October 15 to 19, 2005.  相似文献   
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