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481.
Parkinsonism is associated with major changes in neuronal activity throughout the cortico-basal ganglia loop. Current measures quantify changes in baseline neuronal and network activity but do not capture alterations in information propagation throughout the system. Here, we applied a novel non-invasive magnetic stimulation approach using a custom-made mini-coil that enabled us to study transmission of neuronal activity throughout the cortico-basal ganglia loop in both normal and parkinsonian primates. By magnetically perturbing cortical activity while simultaneously recording neuronal responses along the cortico-basal ganglia loop, we were able to directly investigate modifications in descending cortical activity transmission. We found that in both the normal and parkinsonian states, cortical neurons displayed similar multi-phase firing rate modulations in response to magnetic stimulation. However, in the basal ganglia, large synaptically driven stereotypic neuronal modulation was present in the parkinsonian state that was mostly absent in the normal state. The stimulation-induced neuronal activity pattern highlights the change in information propagation along the cortico-basal ganglia loop. Our findings thus point to the role of abnormal dynamic activity transmission rather than changes in baseline activity as a major component in parkinsonian pathophysiology. Moreover, our results hint that the application of transcranial magnetic stimulation (TMS) in human patients of different disorders may result in different neuronal effects than the one induced in normal subjects.  相似文献   
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Objective. To ascertain differences in the interpretation of spirometry and peak flow measurement between primary care (several practioners and nurses) and specialists in patients with a pre-existing diagnosis of asthma and chronic obstructive pulmonary disease (COPD). Design. A randomized, prospective cohort study of 98 patients with a pre-existing diagnosis of asthma or COPD. Two chest specialists independently interpreted the peak flow and spirometric data and they were also blinded to the primary care results. Results. There was total agreement in interpretation of the data between general practitioners and specialists in only 20 (20.4%). Levels of diagnostic agreement were highest between the two chest specialists (55%) and lowest between the general practice records and the diagnosis assigned by general practitioners (16%). Disagreement between general practitioners and the two chest specialists was consistent (38%) indicating systematic differences in interpretation. Conclusions. This study raises concerns about differences in the interpretation of spirometry and peak expiratory flow rates in general and hospital practice and the guidelines on which these interpretations are based.  相似文献   
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PurposeEdaravone (MCI-186) is a newly developed antioxidative radical scavenger for the treatment of acute cerebral infarction, exerting neuroprotective effects against ischemic insult. The neuroprotective effects of edaravone on pilocarpine-induced seizures in rats were investigated.MethodsRats were treated intraperitoneally with saline or edaravone (1–30 mg/kg), applied 30 min before pilocarpine hydrochloride (330 mg/kg). The onset of status epilepticus (SE) and mortality were recorded for a period of at least 3 days. The cell loss and immunoreactivities of nitric oxide synthase (NOS) in the hippocampus from control and the day 3 rats after SE, treated with saline or edaravone, were evaluated.ResultsEdaravone (1 mg/kg) significantly prevented cell loss in the hippocampus after SE while easier inducing SE. The higher dose of drug could not induce SE significantly but tended to increase the rate of mortality. Inducible NOS (iNOS) expression was significantly decreased in the hippocampus from day 3 rats treated with 1 mg/kg edaravone, compared with saline group, while neuronal NOS (nNOS) and iNOS significantly increased in the hippocampus treated with saline, compared with control group. Significant alteration of endothelial NOS (eNOS) expression in the hippocampus among control group, saline group, and edaravone group was not shown.ConclusionsEdaravone may act as a neuroprotector for the hippocampus after SE by reducing at least iNOS although the low dose of drug easier induces SE because of preventing an endogenous antiepileptic effect of NO.  相似文献   
486.
We investigated the necessity of preparation for blood transfusion in gastric cancer surgery to save costs for blood typing, antibody screening, cross-matching, and disposal of the blood product. The subjects of the study were 52 patients who underwent gastric cancer surgery at our department between 2000 and 2004. The requirement for blood transfusion during surgery was investigated in terms of patient characteristics, hemoglobin before surgery, and performance status as well as treatment regimen. Furthermore, economic effects were investigated when typing and screening (T&S) were performed instead of typing and cross-matching (T&X). Of 9 patients who received blood transfusion, 8 had gastric cancer of stage IIIB or higher, or underwent combined resection. Blood transfusion was not used in surgery for patients with early gastric cancer. The volumes of blood prepared, lost, and disposed of in 28 patients who underwent T&X were 831.3+/-249.4, 219.3+/-228.5 and 600+/-333.1 ml, respectively, whereas the blood loss in 24 patients who underwent T&S was 161.1+/-95.6 ml; this difference had a major economic effect. The practice of T&S for patients undergoing gastric surgery in the absence of combined resection for early gastric cancer seems to be a safe and cost-effective practice that abrogates disposal of blood in hospital management.  相似文献   
487.
Evidence indirectly implicates the amygdala as the primary processor of emotional information used by cortex to drive appropriate behavioral responses to stimuli. Taste provides an ideal system with which to test this hypothesis directly, as neurons in both basolateral amygdala (BLA) and gustatory cortex (GC)-anatomically interconnected nodes of the gustatory system-code the emotional valence of taste stimuli (i.e., palatability), in firing rate responses that progress similarly through "epochs." The fact that palatability-related firing appears one epoch earlier in BLA than GC is broadly consistent with the hypothesis that such information may propagate from the former to the latter. Here, we provide evidence supporting this hypothesis, assaying taste responses in small GC single-neuron ensembles before, during, and after temporarily inactivating BLA in awake rats. BLA inactivation (BLAx) changed responses in 98% of taste-responsive GC neurons, altering the entirety of every taste response in many neurons. Most changes involved reductions in firing rate, but regardless of the direction of change, the effect of BLAx was epoch-specific: while firing rates were changed, the taste specificity of responses remained stable; information about taste palatability, however, which normally resides in the "Late" epoch, was reduced in magnitude across the entire GC sample and outright eliminated in most neurons. Only in the specific minority of neurons for which BLAx enhanced responses did palatability specificity survive undiminished. Our data therefore provide direct evidence that BLA is a necessary component of GC gustatory processing, and that cortical palatability processing in particular is, in part, a function of BLA activity.  相似文献   
488.
AIM: To ascertain whether constitutive androstane receptor (CAR) activation by 1,4-bis-[2-(3,5,- dichloropyridyloxy)] benzene (TCPOBOP) modulates steatohepatitis in the methionine choline-deficient (MCD) diet-fed animal.METHODS: C57/BL6 wild-type mice were fed the MCD or standard diet for 2 wk and were treated with either the CAR agonist, TCPOBOP, or the CAR inverse agonist, androstanol.RESULTS: Expression of CYP2B10 and CYP3A11, known CAR target genes, increased 30-fold and 45-fold, respectively, in TCPOBOP-treated mice fed the MCD diet. TCPOBOP treatment reduced hepatic steatosis (44.6 + 5.4% vs 30.4 + 4.5%, P 〈 0.05) and serum triglyceride levels (48 + 8 vs 20 + 1 mg/dL, P 〈 0.05) in MCD diet- fed mice as compared with the standard diet-fed mice. This reduction in hepatic steatosis was accompanied by an increase in enzymes involved in fatty acid microsomal co-oxidation and peroxisomal p-oxidation, namely CYP4A10, LPBE, and 3-ketoacyI-CoA thiolase. The reduction in steatosis was also accompanied by a reduction in liver cell apoptosis and inflammation. In contrast, androstanol was without effect on any of the above parameters.CONCLUSION: CAR activation stimulates induction of genes involved in fatty acid oxidation, and ameliorates hepatic steatosis, apoptosis and inflammation.  相似文献   
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490.
Microalbuminuria and aortic stiffness are associated with high mortality in type 2 diabetic patients. We tested the hypothesis that the presence of microalbuminuria correlates with aortic stiffness and insulin resistance in type 2 diabetic patients. The study consisted of 36 Japanese patients with type 2 diabetes and microalbuminuria (age: 56+/-9 years, mean+/-S.D.) and a control group of 44 age-matched patients with normoalbuminuria (56+/-7 years). Brachial-ankle pulse wave velocity (BaPWV) was measured by automatic oscillometric method. BaPWV was used as an index of atherosclerosis. The BaPWV was higher in the microalbuminuria group than in the normoalbuminuria group (p<0.005). Fasting plasma glucose (p<0.05) and insulin concentrations (p<0.005), and the homeostasis model assessment (HOMA) index (p<0.0005), were higher in the microalbuminuria group than in the normoalbuminuria group. Multiple regression analysis showed that urinary albumin excretion was independently predicted by BaPWV and HOMA index. Our results indicate that the presence of microalbuminuria in Japanese patients with type 2 diabetes is characterized by increased aortic stiffness and insulin resistance, and that the BaPWV, HOMA index are independent predictors of urine albumin excretion.  相似文献   
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