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111.
Lumbosacral epidural lipomatosis: MRI grading   总被引:3,自引:0,他引:3  
Lumbosacral epidural lipomatosis (LEL) is characterized by excessive deposition of epidural fat (EF). The purpose of our retrospective study was to quantify normal and pathologic amounts of EF in order to develop a reproducible MRI grading of LEL. In this study of 2528 patients (1095 men and 1433 women; age range 18–84 years, mean age 47.3 years) we performed a retrospective analysis of MRI exams. We obtained four linear measurements at the axial plane parallel and tangent to the superior end plate of S1 vertebral body: antero-posterior diameter of dural sac (A-Pd DuS), A-Pd of EF, located ventrally and dorsally to the DuS, and A-Pd of the spinal canal (Spi C). We calculated (a) DuS/EF index and (b) EF/Spi C index. We developed the following MRI grading of LEL: normal, grade 0: DuS/EF index ≥1.5, EF/Spi C index ≤40%; LEL grade I: DuS/EF index 1.49–1, EF/Spi C index 41–50% (mild EF overgrowth); LEL grade II: DuS/EF index 0.99–0.34, EF/Spi C index 51–74% (moderate EF overgrowth); LEL grade III: DuS/EF index ≤0.33, EF/Spi C index ≥75% (severe EF overgrowth). The MRI exams were evaluated independently by three readers. Intra- and interobserver reliabilities were obtained by calculating Kappa statistics. The MRI grading showed the following distribution: grade 0, 2003 patients (79.2%); LEL grade I, 308 patients (12.2%); LEL grade II, 165 patients (6.5%); and LEL grade III, 52 patients (2.1%). The kappa coefficients for intra- and interobserver agreement in a four-grade classification system were substantial to excellent: intraobserver, kappa range 0.79 [95% confidence interval (CI), 0.65–0.93] to 0.82 (95% CI, 0.70–0.95); interobserver, kappa range 0.76 (95% CI, 0.62–0.91) to 0.85 (95% CI, 0.73–0.97). In LEL grade I, there were no symptomatic cases due to fat hypertrophy. LEL grade II was symptomatic in only 24 cases (14.5%). In LEL grade III, all cases were symptomatic. A subgroup of 22 patients (42.3%) showed other substantial spinal pathologies (e.g., disk herniation). By means of simple reproducible measurements and indexes MRI grading enables a distinction between mild, moderate, and severe EF hypertrophy. Kappa statistics indicate that LEL can be reliably classified into a four-grade system by experienced observers.  相似文献   
112.
Intravascular ultrasound-guided wiring for chronic total occlusion.   总被引:1,自引:0,他引:1  
This report describes a wiring technique for a blunt chronic total occlusion with a side branch at the site of occlusion for which the operator has difficulty of awareness of the proper entry point angiographically.  相似文献   
113.
BackgroundThe bicuspid aortic valve (BAV) affects 0.5 to 2% of the population and is associated with valve and aortic alterations. There is a lack of studies on the profile of these patients in the Brazilian population.ObjectiveTo describe the profile of patients with BAV undergoing valve and/or aortic surgery in a tertiary cardiology center, in addition to the outcomes related to the intervention.MethodsRetrospective cohort including 195 patients (mean age 54±14 years, 73.8% male) diagnosed with BAV who underwent surgical approach (valvular and/or aorta) from 2014 to 2019. Clinical data, echocardiographic and tomographic studies were evaluated, as well as characteristics of the intervention and events in 30 days. A value of p<0.05 was considered statistically significant.ResultsWe found a high prevalence of aortic aneurysm (56.5%), with a mean diameter of 46.9±10.2 mm. Major aortic regurgitation was found in 25.1% and major aortic stenosis in 54.9%. Isolated aortic valve surgery was performed in 48.2%, isolated aortic surgery in 6.7% and combined surgery in 45.1%. The 30-day mortality was 8.2%. In the multivariate analysis, the predictors of the combined outcome at 30 days (death, atrial fibrillation and reoperation) were age (OR 1.044, 95% CI 1.009-1.081, p=0.014) and left ventricular mass index (OR 1.009, 95% CI 1.000-1.018, p=0.044).ConclusionPatients with BAV approached in our service have a higher incidence of aortopathy, with the additional need to evaluate the aorta with computed tomography or magnetic resonance imaging.  相似文献   
114.
115.

An analysis is presented of a recent evolutionary process in Brazil of two political and social movements that eventually joined to further common goals of reducing food and nutritional insecurity, and incorporating human rights into national laws and policy measures. A brief history is provided as background. The promotion of human rights, particularly of economic, social and cultural rights provides an important link between recent political and social activism, and national efforts to reduce food and nutritional insecurity. Concrete results of political and social activism are examined, which include the 1999 National Food and Nutrition Policy, the 1999 Social Pact to Reduce Iron‐Deficiency Anaemia, renewed efforts to incorporate economic, social and cultural rights in the National Human Rights Plan, the establishment of a national food security and nutrition network, and the formation of State food security councils. Specific and generalised lessons are also drawn from the Brazilian experience.  相似文献   
116.
OBJECTIVES:To evaluate predictors of the response to doxazosin, a selective alpha-adrenoceptor antagonist, when used for the treatment of lower urinary tract symptoms in men with Parkinson''s disease.METHODS:In a prospective study, 33 consecutive men (mean age 59.2±7.0 years) with Parkinson''s disease and lower urinary tract symptoms were evaluated. Neurological dysfunction was assessed with the Unified Parkinson''s Disease Rating Scale. Urological assessment was performed at baseline and after 12 weeks of treatment with 4 mg/day of extended-release doxazosin, including symptom evaluation with the International Continence Society male short-form questionnaire, an assessment of the impact of lower urinary tract symptoms on quality of life and urodynamics. Clinical and urodynamic predictors of response were specifically evaluated.RESULTS:Compared with the score at baseline, the total International Continence Society male short-form score was reduced after doxazosin administration, from 17.4±7.5 to 11.1±6.9 (p<0.001). The impact of lower urinary tract symptoms on quality of life was also significantly reduced, from 1.8±1.1 to 1.0±1.0 (p<0.001) and the maximum urinary flow varied from 9.3±4.4 to 11.2±4.6 ml/s (p = 0.025). The severity of neurological impairment was the only predictor of the clinical response. Additionally, patients with a Unified Parkinson''s Disease Rating Scale score lower than 70 had a significantly higher chance of clinical improvement with doxazosin treatment than those with higher Unified Parkinson''s Disease Rating Scale scores did (RR = 3.10, 95% CI = [1.15 to 5.37], p = 0.011).CONCLUSIONS:Doxazosin resulted in the improvement of lower urinary tract symptoms and the maximum flow rate and was well tolerated in men with Parkinson''s disease. The response to treatment is dependent on the severity of neurological disability.  相似文献   
117.

Background  

Brain metastases (BM) are the most common form of intracranial cancer. The incidence of BM seems to have increased over the past decade. Recursive partitioning analysis (RPA) of data from three Radiation Therapy Oncology Group (RTOG) trials (1200 patients) has allowed three prognostic groups to be identified. More recently a simplified stratification system that uses the evaluation of three main prognostics factors for radiosurgery in BM was developed.  相似文献   
118.
Abstract: A growing body of evidence has pointed to the blockade of the N‐methyl‐d ‐aspartate (NMDA) receptor signaling as a potential therapeutic target for the treatment of major depression. The present study was aimed to evaluate behavioural and molecular effects of the chronic treatment with ketamine and imipramine in rats. To this aim, rats were 14 days treated once a day with ketamine (5, 10 and 15 mg/kg) and imipramine (10, 20 and 30 mg/kg) and then subjected to the forced swimming and open‐field tests. Ketamine and imipramine, at the all doses tested, reduced immobility time, and increased both climbing and swimming time of rats compared to the saline group, without affecting spontaneous locomotor activity. Brain‐derived neurotrophic factor (BDNF) hippocampal levels were assessed in imipramine‐ and ketamine‐treated rats by ELISA sandwich assay. Chronic administration of both drugs, ketamine and imipramine, did not modify BDNF protein levels in the rat hippocampus. In conclusion, our findings demonstrate for the first time that chronic administration of acute inactive doses of ketamine (5 mg/kg) becomes active after chronic treatment, while no signs of tolerance to the behavioural effects of ketamine were observed after chronic administration of acute active doses (10 and 15 mg/kg). Finally, these findings further support the hypothesis that NMDA receptor could be a new pharmacological target for the treatment of mood disorders.  相似文献   
119.
BACKGROUND AND OBJECTIVE: Lowering BP to normal levels without quality of life deterioration is the most important means of reducing cardiovascular risk. Recent studies have challenged the position of beta-adrenoceptor antagonists (beta-blockers) as first-line antihypertensive drugs. Nebivolol is a third-generation, highly selective beta(1)-blocker that causes vasodilation through nitric oxide (NO) release. This meta-analysis investigates the efficacy and tolerability of nebivolol compared with other antihypertensive drugs and placebo in patients with hypertension. METHODS: Twelve randomized controlled studies were included in which nebivolol 5 mg once daily was compared with the recommended clinical doses of other antihypertensive drugs (n = 9), placebo (n = 2), and both (n = 1). The clinical studies were selected after a MEDLINE search up to 2007 using the key words 'nebivolol' and 'hypertension.' RESULTS: Antihypertensive response rates (the percentage of patients achieving target BP levels or a defined DBP reduction) were higher with nebivolol than with ACE inhibitors (odds ratio [OR] 1.92; p = 0.001) and all antihypertensive drugs combined (OR 1.41; p = 0.001) and similar to beta-blockers, calcium channel antagonists (CCAs) and the angiotensin receptor antagonist (ARA) losartan. Moreover, a higher percentage of patients receiving nebivolol achieved target BP levels compared with patients treated with losartan (OR 1.98; p = 0.004), CCAs (OR 1.44; p = 0.024), and all antihypertensive drugs combined (OR 1.35; p = 0.012). The percentage of patients experiencing adverse events did not differ between nebivolol and placebo; adverse event rates were significantly lower with nebivolol than losartan (OR 0.52; p = 0.016), other beta-blockers (OR 0.56; p = 0.007), nifedipine (OR 0.49; p < 0.001), and all antihypertensive drugs combined (OR 0.59; p < 0.001). CONCLUSION: Results of previous pharmacokinetic studies suggest that nebivolol 5 mg may not conform completely to the definition of a classic beta-blocker demonstrating additional antihypertensive effect due to endothelial NO release-mediated vasodilation. This meta-analysis showed that nebivolol 5 mg achieved similar or better rates of treatment response and BP normalization than other drug classes and other antihypertensive drugs combined, with similar tolerability to placebo and significantly better tolerability than losartan, CCAs, other beta-blockers, and all antihypertensive drugs combined. Although not definitive, this meta-analysis suggests that nebivolol 5 mg is likely to have advantages over existing antihypertensives and may have a role in the first-line treatment of hypertension.  相似文献   
120.
In order to investigate the involvement of mGlu1 and mGlu5 metabotropic glutamate receptors in the development of postischemic neuronal death, we examined the effects of selective agonists and antagonists in models of cerebral ischemia in vitro and in vivo. In murine cortical cell cultures and rat organotypic hippocampal slices exposed to oxygen and glucose deprivation (OGD), the mGlu1 antagonists 1-aminoindan-1,5-dicarboxylic acid (AIDA; 300 microM), (S)-(+)-2-(3'-carboxybicyclo[1.1.1]pentyl)-glycine (CBPG; 300 microM), 7-hydroxyiminocyclopropan[b]chromen-1a-carboxylic acid ethyl ester (CPCCOEt; 10-30 microM) and (+)-2-methyl-4-carboxyphenylglycine (LY367385; 30-100 microM) reduced neuronal loss when added to the medium during OGD and the subsequent 24-h recovery period. On the contrary, the potent and selective mGlu5 antagonist methyl-6-(phenylethynyl)-pyridine (MPEP; 0.1-1 microM) did not exhibit neuroprotection in any of these in vitro models. Incubation with the nonselective mGlu1 and mGlu5 agonist 3,5-dihydroxyphenylglycine (3,5-DHPG; 300 microM) but not with the mGlu5 agonist (RS)-2-chloro-5-hydroxyphenylglycine (CHPG; 1 mM) enhanced the severity of OGD-induced neuronal damage. In gerbils subjected to global ischemia, intracerebroventricular administration of AIDA (100 nmol two times) or CBPG (300 nmol, two times) afforded consistent protection against CA1 pyramidal cell death, whereas MPEP (10 pmol i.c.v two times and 10 mg/kg i.p two times) failed to reduce postischemic hippocampal damage. Our results suggest that activation of mGlu1 but not mGlu5 receptor contributes to postischemic neuronal injury.  相似文献   
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