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101.
Methylmercury is an environmental contaminant with special selectivity for cerebellar granule cells. The aim of this study was to determine the effect of long-term methylmercury exposure on cell viability and cellular proteome in cultured cerebellar granule cells. Primary cultures of mice cerebellar granule cells were treated with 0-300 nM methylmercury at 2 days in vitro (div) and afterwards the cells were harvested at 12 div. 100 nM methylmercury produced loss of cell viability, reduced intracellular glutamate content and increased lipid peroxidation. Glutamate transport was not modified by methylmercury treatment. Cell death induced by 300 nM methylmercury at 8 div was apoptotic without producing activation of caspase 3. Extracts of total protein were separated by 2D electrophoresis. Around 800 protein spots were visualized by silver staining in SDS-polyacrylamide gels. Gel images were digitized and protein patterns were analysed by image analysis. Several spots were identified through a combination of peptide mass fingerprinting and matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). The mitochondrial protein 3-ketoacid-coenzyme A transferase I was decreased up to 39% of controls at concentrations of methylmercury that did not produce cytotoxic effects, whereas the cytoplasmic proteins lactate dehydrogenase chain B and actin did not change.  相似文献   
102.
Colorectal cancer (CRC) is the second most common cause of death due to cancer causing death in Europe, accounting for more than 200,000 deaths per year. Prognosis strongly depends on stage at diagnosis, and the disease can be cured in most cases if diagnosed at an early stage. We aimed to assess trends and recent developments in 5-year relative survival in European countries, with a special focus on age, stage at diagnosis and anatomical cancer subsite. Data from 25 population-based cancer registries from 16 European countries collected in the context of the EUROCARE-4 project were analyzed. Using period analysis, age-adjusted and age-specific 5-year relative survival was calculated by country, European region, stage and cancer subsite for time periods from 1988-1990 to 2000-2002. Survival substantially increased over time in all European regions. In general, increases were more pronounced in younger than in older patients, for earlier than for more advanced cancer stages and for rectum than for colon cancer. Substantial variation of CRC survival between European countries and between age groups persisted and even tentatively increased over time. There is a huge potential for reducing the burden of CRC in Europe by more widespread and equal delivery of existing options of effective early detection and curative treatment to the European population.  相似文献   
103.

Introduction

The clinical benefit of thrombolytic treatment over heparin in patients with pulmonary embolism without hemodynamic compromise remains controversial. In these patients bolus tenecteplase has the potential to provide an effective and safe thrombolysis.

Methods

We evaluated the effect of tenecteplase on right ventricle dysfunction (RVD) assessed by echocardiography in hemodynamically stable patients with PE in a multicenter, randomized, double-blind, placebo-controlled study. RVD was defined as right/left ventricle end-diastolic dimension ratio > 1 in the apical 4-chamber view. Patients were randomized to receive weight-adjusted single-bolus tenecteplase or placebo. All patients received unfractionated heparin. Reduction of RVD at 24 hours was the primary efficacy end-point and was evaluated by an independent committee unaware of treatment allocation.

Results

Overall, 58 patients were randomized. Echocardiograms were adequate for efficacy analysis in 51 patients, 23 randomized to tenecteplase and 28 to placebo. The reduction of right to left ventricle end-diastolic dimension ratio at 24 hours was 0.31 ± 0.08 in patients randomized to tenecteplase as compared to 0.10 ± 0.07 in patients randomized to placebo (p = 0.04). One patient randomized to tenecteplase suffered a clinical event (recurrent pulmonary embolism) in comparison to three patients randomized to placebo (1 recurrent pulmonary embolism; 1 clinical deterioration and 1 non pulmonary embolism-related death). Two non fatal major bleedings occurred with tenecteplase (1 intracranial) and one with placebo.

Conclusion

In hemodynamically stable patients with PE, treatment with single bolus tenecteplase is feasible at the same dosages used for acute myocardial infarction and is associated with reduction of RVD at 24 hours. Whether this benefit is associated with an improved clinical outcome without excessive bleeding is currently explored in a large clinical trial.  相似文献   
104.
In this open-label, single-center study, eight healthy men each received a single 500-mg dose of [14C]doripenem, containing 50 μCi of [14C]doripenem, administered as a 1-h intravenous infusion. The concentrations of unchanged doripenem and its primary metabolite (doripenem-M-1) resulting from β-lactam ring opening were measured in plasma and urine by a validated liquid chromatography method coupled to a tandem mass spectrometry assay. Total radioactivity was measured in blood, plasma, urine, and feces by liquid scintillation counting. Further metabolite profiling was conducted on urine samples using liquid chromatography coupled to radiochemical detection and high-resolution mass spectrometry. Unchanged doripenem and doripenem-M-1 accounted for means of 80.7% and 12.7% of the area under the plasma total-radioactivity-versus-time curve (area under the concentration-time curve extrapolated to infinity) and exhibited elimination half-lives of 1.1 and 2.5 h, respectively. Total clearance of doripenem was 16 liters/h, and renal clearance was 12.5 liters/h. At 7 days after the single dose, 95.3% of total doripenem-related radioactivity was recovered in urine and 0.72% in feces. A total mean of 97.2% of the administered dose was excreted in the urine as unchanged doripenem (78.7% ± 5.7%) and doripenem-M-1 (18.5% ± 2.6%). Most of the urinary recovery occurred within 4 h of dosing. Three additional minor metabolites were identified in urine: the glycine and taurine conjugates of doripenem-M-1 and oxidized doripenem-M-1. These results show that doripenem is predominantly eliminated in urine as unchanged drug, with only a fraction metabolized to doripenem-M-1 and other minor metabolites.  相似文献   
105.
BACKGROUND: Fatty acid-binding protein 4 (FABP4) has been linked to metabolic syndrome development, diabetes, and arteriosclerosis, but the role of FABP4 in target organ damage has not been assessed. We evaluated whether plasma FABP4 is associated with renal dysfunction in type 2 diabetic patients. METHODS: In 263 individuals (161 type 2 diabetic patients and 102 healthy nondiabetic controls), we analyzed the correlation between FABP4 and creatinine or glomerular filtration index (MDRD-GFR) regarding the presence or absence of microalbuminuria. Patients with severe chronic kidney disease (MDRD-GFR <30 mL/min/1.73 m(2)) or albuminuria were not included. RESULTS: FABP4 concentrations were higher in diabetic patients with MDRD-GFR <60 mL/min/1.73 m(2) (P <0.001). We observed a significant, direct correlation between FABP4 and creatinine (r = 0.446, P <0.001) and an inverse correlation between FABP4 and MDRD-GFR (r = -0.511, P <0.001) in type 2 diabetic patients, but not in nondiabetic individuals. These correlations were sustained when only those patients without microalbuminuria were analyzed (r = 0.414, P <0.001 and r = -0.510, P <0.001, respectively). Type 2 diabetic patients with FABP4 in the highest tertile compared with those in the lower tertiles had increased adjusted odds ratios for moderate renal dysfunction [7.5 (95%CI 1.8-30.7), P = 0.005 and 15.3 (3.1-76.4), P = 0.001; respectively], independent of microalbuminuria. CONCLUSIONS: High FABP4 plasma concentrations are associated with high plasma creatinine and low MDRD-GFR in patients with type 2 diabetes even in the absence of microalbuminuria or clinically relevant alterations of creatinine and MDRD-GFR values. FABP4 concentrations should be taken into consideration as an early marker of kidney damage in patients with type 2 diabetes.  相似文献   
106.
Previous MR studies have established that bilateral transverse sinus stenosis (BTSS) predicts idiopathic intracranial hypertension without papilledema (IIHWOP) in migraine. However, it is uncertain whether BTSS identifies IIHWOP in patients with chronic tension-type headache (CTTH): using cerebral MR venography this study aimed to address this question.In a prospective study from February 2002 to December 2006, 198 consecutive patients with CTTH underwent MR venography. Of these patients, 58 underwent lumbar puncture to measure cerebrospinal fluid (CSF) pressure. MR venography and lumbar puncture were also performed in 45 age-matched control subjects. BTSS was considered present when the signal flow was poor or lacking (flow gap) in the mid-lateral portion of both transverse sinuses. IIHWOP was diagnosed if the patient met the diagnostic criteria for idiopathic intracranial hypertension and did not have papilledema. Among the 198 patients with CTTH who underwent MR venography, 18 (9%) had BTSS. Thirteen of these 18 patients with BTSS underwent lumbar puncture, and nine (69.2%) had IIHWOP. CSF opening pressure was normal in all 45 patients as well as in all 45 controls with normal MR venography.These data suggest that BTSS on MR venography is associated with increased intracranial pressure in the absence of papilledema in patients with headache mimicking CTTH.  相似文献   
107.
Lectin-like oxyLDL receptor-1 (LOX-1) has recently been suggested to be involved in smooth muscle cell (SMC) proliferation and neointima formation in injured blood vessels. This study evaluates the effect of the nonvolatile fraction (NVF), the antioxidant component of bergamot essential oil (BEO), on LOX-1 expression and free radical generation in a model of rat angioplasty. Common carotid arteries injured by balloon angioplasty were removed after 14 days for histopathological, biochemical, and immunohistochemical studies. Balloon injury led to a significant restenosis with SMC proliferation and neointima formation, accompanied by increased expression of LOX-1 receptor, malondialdehyde and superoxide formation, and nitrotyrosine staining. Pretreatment of rats with BEO-NVF reduced the neointima proliferation together with free radical formation and LOX-1 expression in a dose-dependent manner. These results suggest that natural antioxidants may be relevant in the treatment of vascular disorders in which proliferation of SMCs and oxyLDL-related endothelial cell dysfunction are involved.  相似文献   
108.
BACKGROUND: Traditional cancer-survival analyses provide data on cancer management at the beginning of a study period, and are often not relevant to current practice because they refer to survival of patients treated with older regimens that might no longer be used. Therefore, shortening the delay in providing survival estimates is desirable. Period analysis can estimate cancer survival by the use of recent data. We aimed to apply the period-analysis method to data that were collected by European cancer registries to estimate recent survival by country and cancer site, and to assess survival changes in Europe. We also compared our findings with data on cancer survival in the USA from the US SEER (Surveillance, Epidemiology, and End Results) programme. METHODS: We analysed survival data for patients diagnosed with cancer in 2000-02, collected from 47 of the European cancer registries participating in the EUROCARE-4 study. 5-year period relative survival for patients diagnosed in 2000-02 was estimated as the product of interval-specific relative survival values of cohorts with different lengths of follow-up. 5-year survival profiles for patients diagnosed in 2000-02 were estimated for the European mean and for five European regions, and findings were compared with US SEER registry data for patients diagnosed in 2000-02. A 5-year survival profile for patients diagnosed in 1991-2002 and a 10-year survival profile for patients diagnosed in 1997-2002 were also estimated by the period method for all malignancies, by geographical area, and by cancer site. FINDINGS: For all cancers, age-adjusted 5-year period survival improved for patients diagnosed in 2000-02, especially for patients with colorectal, breast, prostate, and thyroid cancer, Hodgkin's disease, and non-Hodgkin lymphoma. The European mean age-adjusted 5-year survival calculated by the period method for 2000-02 was high for testicular cancer (97.3% [95% CI 96.4-98.2]), melanoma (86.1% [84.3-88.0]), thyroid cancer (83.2% [80.9-85.6]), Hodgkin's disease (81.4% [78.9-84.1]), female breast cancer (79.0% [78.1-80.0]), corpus uteri (78.0% [76.2-79.9]), and prostate cancer (77.5% [76.5-78.6]); and low for stomach cancer (24.9% [23.7-26.2]), chronic myeloid leukaemia (32.2% [29.0-35.7]), acute myeloid leukaemia (14.8% [13.4-16.4]), and lung cancer (10.9% [10.5-11.4]). Survival for patients diagnosed in 2000-02 was generally highest for those in northern European countries and lowest for those in eastern European countries, although, patients in eastern European had the highest improvement in survival for major cancer sites during 1991-2002 (colorectal cancer from 30.3% [28.3-32.5] to 44.7% [42.8-46.7]; breast cancer from 60% [57.2-63.0] to 73.9% [71.7-76.2]; for prostate cancer from 39.5% [35.0-44.6] to 68.0% [64.2-72.1]). For all solid tumours, with the exception of stomach, testicular, and soft-tissue cancers, survival for patients diagnosed in 2000-02 was higher in the US SEER registries than for the European mean. For haematological malignancies, data from US SEER registries and the European mean were comparable in 2000-02, except for non-Hodgkin lymphoma. INTERPRETATION: Cancer-service infrastructure, prevention and screening programmes, access to diagnostic and treatment facilities, tumour-site-specific protocols, multidisciplinary management, application of evidence-based clinical guidelines, and recruitment to clinical trials probably account for most of the differences that we noted in outcomes.  相似文献   
109.
The common way to analyse the prognostic role of selected variables in cutaneous melanoma patients is by means of Cox proportional hazard model. The prognostic effect of the simultaneous presence of more than one independent variable in the same patient is, however, difficult to establish. This hampers the possibility of tailoring a survival expectance for a selected patient as well as to communicate it to the patient himself/herself. The objectives of the study were to compare information on cutaneous melanoma prognosis from multivariate Cox proportional hazard model and from Classification And Regression Trees analysis. Classification And Regression Trees analysis is an automatic method that splits data by means of a binary recursive process creating a 'tree' of groups with different profiles according to the analysed outcome, for example, the risk of death. This approach automatically produces data that is easily interpreted by clinicians. A total of 1403 invasive cutaneous melanoma patients, 1110 from the Tuscan Cancer Registry and 293 from the Reggio Emilia Cancer Registry, Italy, were included. Cases were incident during 1996-2001 and followed up at the end of 2003. Cox proportional hazard model and Classification And Regression Trees analysis were applied to the following variables: age, sex, Breslow thickness, Clark level, registry, subsite and morphologic type. The Classification And Regression Trees analysis identified 10 categories with statistically different survival; this results were summarized into six classes of different risks based on Breslow thickness, age and sex. The best prognostic group (5-year observed survival, 98.1%) included those subjected with Breslow less than 0.94 mm and age 19-44 years. The same thickness but an older age (50-69 years) was associated with a statistically significant different prognosis (5-year observed survival, 92.8%). The Cox proportional hazard model found sex, age, Breslow thickness, Clark and morphologic type to have a significant independent prognostic value. In conclusion, compared with the conventional approach based on Cox hazard model, Classification And Regression Trees analysis produces data closer to the clinical need of defining the prognostic profile of a specific patient. This may help the clinician both in the communication of risk and in the follow-up strategy.  相似文献   
110.
M100240 is a thioester of MDL 100,173, a dual angiotensin-converting enzyme (ACE)/neutral endopeptidase (NEP) inhibitor. Clinical studies have shown that M100240 is capable of decreasing ACE activity and angiotensin II concentrations while increasing plasma renin activity and potentiating the effects of atrial natriuretic peptide. This may result in a unique treatment benefit in disease states characterized by intravascular volume or sodium overload or increased venous pressure. The pharmacokinetics of MDL 100,173 were evaluated in 30 healthy subjects in an open-label, randomized, 2-period crossover design. Subjects received a single oral dose of 50 mg of M100240 administered with a high-fat meal and separately under fasted conditions. Serial plasma concentrations of M100240 and MDL 100,173 were analyzed, and pharmacokinetic parameters were calculated with noncompartmental methods. The intrasubject percent coefficient of variation for MDL 100,173 C(max) and AUC(0-24h) were less than 20%, indicating that this agent is a moderately variable drug. Although AUC(0-24h) was within the protocol-defined range of 80% to 125%, the lower limit of the 90% confidence interval for C(max) fell outside of the 70% to 143% range. Absence of a food effect on the pharmacokinetic profile of 50 mg of M100240 could therefore not be demonstrated. This finding is not surprising based on the documented food effect with the sulfhydryl-containing ACE inhibitor, captopril. Clinical significance of this pharmacokinetic food effect is unlikely, as the magnitude of pharmacodynamic response is probably better correlated with AUC than a single-point determination of C(max). Single oral doses of 50 mg of M100240 were safe and well tolerated under fed and fasted conditions.  相似文献   
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