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141.
The risk of stroke in patients hospitalized with an acute coronary syndrome (ACS) ranges from <1% to ≥2.5%. The aim of this study was to develop a simple predictive tool for bedside risk estimation of in-hospital ischemic stroke in patients with ACS to help guide clinicians in the acute management of these high-risk patients. Data were obtained from 63,118 patients enrolled from April 1999 to December 2007 in the Global Registry of Acute Coronary Events (GRACE), a multinational registry involving 126 hospitals in 14 countries. A regression model was developed to predict the occurrence of in-hospital ischemic stroke in patients hospitalized with an ACS. The main study outcome was the development of ischemic stroke during the index hospitalization for an ACS. Eight risk factors for stroke were identified: older age, atrial fibrillation on index electrocardiogram, positive initial cardiac biomarkers, presenting systolic blood pressure ≥160 mm Hg, ST-segment change on index electrocardiogram, no history of smoking, higher Killip class, and lower body weight (c-statistic 0.7). The addition of coronary artery bypass graft surgery and percutaneous coronary intervention into the model increased the prediction of stroke risk. In conclusion, the GRACE stroke risk score is a simple tool for predicting in-hospital ischemic stroke risk in patients admitted for the entire spectrum of ACS, which is widely applicable to patients in various hospital settings and will assist in the management of high-risk patients with ACS.  相似文献   
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Gastric involvement appears quite commonly in systemic sclerosis (SSc). The aim of this study was to evaluate gastric wall motility using ultrasonography, a noninvasive method able to track both filling and emptying of fundus and antrum. The study was performed in 20 SSc patients and 20 healthy control subjects. Gastric filling and emptying were evaluated by transabdominal ultrasonography, measuring changes in fundus and antral areas over a 1-h period after ingestion of a liquid bolus (500 ml of mineral water). Areas of both gastric fundus and antrum at basal evaluation were found to be smaller in SSc patients than in healthy controls. Gastric filling was significantly reduced after ingestion of liquid bolus. Gastric emptying was delayed both in fundus and antrum. No significant differences of gastric wall motility have been observed in different subsets of SSc patients. Our findings show that gastric dysmotility is frequent and severe in SSc patients, contributing to the gastrointestinal disturbances which are very common in this disease.  相似文献   
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ObjectiveThis study aims to assess the prognostic value of acute postoperative seizures (APOS) in patients surgically treated for drug-resistant extra-temporal lobe (ET) epilepsy.MethodsWe studied 77 consecutive patients with ET epilepsy who underwent epilepsy surgery and were followed up for at least 2 years (mean duration of follow-up 6.2 years, range 2–14). Medical charts were reviewed to identify APOS, defined as ictal events with the exception of auras occurring within the first 7 days after surgery. Seizure outcome was determined at annual intervals. Patients who were in Engel Class I at the last contact were classified as having a favourable outcome.ResultsSeizure outcome was favourable in 47 patients (61%). The occurrence of APOS and incompleteness of resection were found to be independently associated with unfavourable outcome in a multiple regression model including all preoperative factors identified as outcome predictors in univariate analysis. Duration of illness was the only independent preoperative predictor of APOS.ConclusionsOur study suggests that APOS may predict long-term outcome in patients undergoing resective surgery for ET epilepsy. Given some study limitations, our findings should be regarded as preliminary and need confirmation from future larger, prospective, multicentre studies.SignificanceCaution may be required in the clinical management of patients experiencing APOS.  相似文献   
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Sciatic nerve traumatic damage very rarely occurs bilaterally. We describe the case of a 67-year-old woman who reported a bilateral traumatic lesion of the sciatic nerve during practice of yoga. Nerve conduction studies showed a bilateral sciatic nerve neuropathy, mostly affecting the peroneal component. Lumbar plexus MRI documented regular anatomical features of the main principal nerve roots with bilateral T2 signal alteration of roots L4, L5 and S1 that extended into the sciatic nerves showing both increase in size, probably related to chronic injury of nerves, and an alteration in diffusion signal that suggested a recent acute overlapped process.  相似文献   
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An array of brain regions in the fronto-parietal and temporal lobes cooperates to process observation and execution of actions performed by other individuals. Using functional MRI, we hypothesized that vegetarians and vegans might show brain responses to mouth actions performed by humans, monkeys, and pigs different from omnivores. We scanned 20 omnivores, 19 vegetarians, and 21 vegans while watching a series of silent videos, which presented a single mouth action performed by a human, a monkey, and a pig. Compared to omnivores, vegetarians and vegans have increased functional connectivity between regions of the fronto-parietal and temporal lobes versus the cerebellum during observation of mouth actions performed by humans and, to the same degree, animals. Vegans also had increased connectivity with the supplementary motor area. During human mouth actions, increased amygdala activity in vegetarians and vegans was found. More critically, vegetarians recruited the right middle frontal gyrus and insula, which are involved in social mirroring, whereas vegans activated the left inferior frontal gyrus and middle temporal gyrus, which are part of the mirror neuron system. Monkey mouth actions triggered language network activity in both groups, which might be due to the attempt to decode monkey mouth gesture, with an additional recruitment of associative temporo-occipital areas in vegans, whereas pig mouth actions activated empathy-related regions, including the anterior cingulum. These results support the role of the action observation–execution matching system in social cognition, which enables us to interact not only with our conspecifics but also with species in phylogenetic proximity to humans.  相似文献   
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Exendin-(9,39) is a competitive antagonist of glucagon-like peptide-1 (GLP-1) at its receptor. However, it is unclear if it has direct and unique effects of its own. We tested the hypothesis that exendin-(9,39) and GLP-1-(9,36)amide have direct effects on hormone secretion and β-cell function as well as glucose metabolism in healthy subjects. Glucose containing [3-3H]glucose was infused to mimic the systemic appearance of glucose after a meal. Saline, GLP-1-(9,36)amide, or exendin-(9,39) at 30 pmol/kg/min (Ex 30) or 300 pmol/kg/min (Ex 300) were infused in random order on separate days. Integrated glucose concentrations were slightly but significantly increased by exendin-(9,39) (365 ± 43 vs. 383 ± 35 vs. 492 ± 49 vs. 337 ± 50 mmol per 6 h, saline, Ex 30, Ex 300, and GLP-1-[9,36]amide, respectively; P = 0.05). Insulin secretion did not differ among groups. However, insulin action was lowered by exendin-(9,39) (25 ± 4 vs. 20 ± 4 vs. 18 ± 3 vs. 21 ± 4 10−4 dL/kg[min per μU/mL]; P = 0.02), resulting in a lower disposition index (DI) during exendin-(9,39) infusion (1,118 ± 118 vs. 816 ± 83 vs. 725 ± 127 vs. 955 ± 166 10−14 dL/kg/min2 per pmol/L; P = 0.003). Endogenous glucose production and glucose disappearance did not differ significantly among groups. We conclude that exendin-(9,39), but not GLP-1-(9,36)amide, decreases insulin action and DI in healthy humans.The incretin hormone glucagon-like peptide-1 (GLP-1) arises by posttranslational processing of preproglucagon in the enteroendocrine L cells distributed throughout the intestine. GLP-1 secretion occurs within minutes of food ingestion, is a potent insulin secretagogue, and suppresses glucagon (1). However, the active form(s) of GLP-1 are rapidly deactivated by a serine protease dipeptidyl peptidase-4, which cleaves the two NH2-terminal amino acids necessary for activation of the GLP-1 receptor (GLP-1R). This enzyme is widely distributed so that the half-life of active GLP-1 in the circulation is ∼1 min (2). The resulting metabolite GLP-1-(9,36) has been proposed as a potential antagonist of GLP-1R, although at present there is no evidence of an effect of this peptide on insulin secretion (3).Exendin-(7,39) is a naturally occurring analog of GLP-1-(7,36) and is an agonist of the GLP-1R. This compound binds to GLP-1R with greater affinity than the natural ligand due to a nine–amino acid COOH-terminal sequence absent in native GLP-1 (4). On the other hand, exendin-(9,39), which arises from the removal of the two NH2-terminal amino acids, is a competitive antagonist of GLP-1 at the GLP-1R (5). It has been used to examine the effects of endogenous GLP-1 secretion on glucose homeostasis (6). Although it is presumed that exendin-(9,39) has no direct effects on glucose metabolism, it alters gastric emptying and capacitance through vagal mechanisms, thereby altering glucose tolerance independent of its ability to inhibit GLP-1-(7,36) effects on insulin and glucagon secretion (7,8). A direct effect of GLP-1-(9,36) signaling on glucose metabolism has been reported (9).The present studies were undertaken to determine whether exendin-(9,39) and GLP-1-(9,36)amide have direct effects on β-cell function, insulin action, glucagon secretion, and glucose metabolism. We did so by infusing glucose in a manner that mimicked the systemic appearance of glucose after ingestion of carbohydrate. Since glucose was infused intravenously, this created a model that resulted in the stimulation of insulin and suppression of glucagon in the absence of a change in endogenous GLP-1 concentrations. Subjects were studied on four occasions: receiving, in random order, saline, exendin-(9,39) infused at 30 pmol/kg/min (Ex 30) and at 300 pmol/kg/min (Ex 300), and GLP-1-(9,36)amide. Glucose turnover was measured on each occasion using [3-3H]glucose; insulin secretion and action were measured using the minimal model.  相似文献   
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