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51.
OBJECTIVES: The purpose of this study was to assess the determinants of mortality in a large group of patients with ischemic cardiomyopathy who are treated medically and the impact of the extent of viable tissue on prognosis. BACKGROUND: Whether the presence of viability drives mortality in patients with ischemic cardiomyopathy who are treated medically and whether the extent of viability is important are issues that are currently unclear. METHODS: Two hundred sixty-one patients with ischemic cardiomyopathy underwent positron emission tomography (PET) for assessment of viability. Prospective follow-up was obtained. RESULTS: Ninety-four patients were revascularized and 167 were not. The cardiac death rate was significantly less in the revascularized patients as compared with medically treated patients (13% vs. 24%, p < 0.05). In the revascularized patients, there was a trend toward better survival in patients with viable myocardium as compared with nonviable myocardium (3.5-year survival, 85% and 75% respectively, p = NS). In the medically treated group, age (hazard ratio [HR] 2.1, 95% confidence interval [CI] 1.2 to 3.7), presence of left bundle branch block (HR 3.4, 95% CI 1.6 to 7.2) and extent of perfusion-metabolism mismatch on PET (HR 1.36, 95% CI 1.1 to 1.6) predicted cardiac death during a median follow-up period of 2.1 years. The risk of cardiac death was not significantly increased when the extent of mismatch was < or =20% (HR 0.97, 95% CI 0.46 to 2.05) but was significantly increased when the extent of mismatch was >20% (HR 3.21, 95% CI 1.38 to 7.49). CONCLUSIONS: Medically treated patients with ischemic cardiomyopathy and large areas of viable myocardium on PET are at high risk for cardiac death.  相似文献   
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The objective of this study was to analyze the feasibility and safety of transradial catheterization in patients with remote surgical cardiac revascularization. Selective catheterization of coronary bypass grafts might be more difficult and time-consuming from the radial artery as compared to the femoral route. This special patient subset has been either excluded or underrepresented in previous studies. Retrospective review was made of 304 cardiac diagnostic procedures performed from January 2001 through December 2004 in patients with coronary artery bypass grafts in a single center. Patients had to be considered eligible for both transradial and transfemoral approach to be included. Cases with double internal mammary or gastroepiploic grafts were excluded. Selection of the arterial access was individualized according to operator preferences. Among diagnostic cases, transradial access was attempted as first choice in 151 cases (left radial in 133) and transfemoral in 154. Total procedural time (41 +/- 22 vs. 40 +/- 23 min), fluoroscopy time (15 +/- 10 vs. 18 +/- 13 min), and dye volume (180 +/- 64 vs. 192 +/- 73 ml) were similar. Crossover rates were 4.0% in the transradial group and 1.3% in transfemoral (P = 0.28). Only two patients in transradial group needed transfemoral access because of failure to catheterize a bypass graft. Transradial angiography of coronary bypass grafts can be performed with similar success rates as compared with transfemoral procedures and without a significant time delay.  相似文献   
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Background: The pleiotropic effects of statins, such as immunomodulation and anti‐inflammatory effects, may also improve periodontal conditions. The aim of the present study is to assess the effectiveness of a dentifrice medicated with 2% atorvastatin in improving clinical periodontal parameters as a complement to non‐surgical periodontal treatment (NSPT). Methods: A randomized, double‐masked clinical trial was performed with two parallel groups: 1) atorvastatin group (NSPT plus medicated 2% atorvastatin dentifrice) and 2) placebo group (NSPT plus placebo dentifrice). The effectiveness of these treatments was assessed using periodontal measurements obtained at baseline and 1 month later. The measurements were probing depth (PD), clinical attachment level (CAL), bleeding on probing (BOP), gingival index (GI), and periodontal inflamed surface area (PISA). Multiple linear regression models were used to compare outcome variables after adjusting for sex, diabetes, and tobacco use. Results: A total of 36 individuals participated in this study (atorvastatin group, n = 18; placebo group, n = 18). Both groups showed improvements in periodontal parameters. The atorvastatin group showed a decrease of 297.63 mm2 in PISA (95% confidence interval = 76.04 to 519.23; P = 0.01), which was significantly greater than the reduction observed in the placebo group. There was also a significantly greater reduction in mean PD, percentage of sites with PD ≥5 mm, mean CAL, percentage of sites with CAL ≥5 mm, BOP, and GI in the atorvastatin group compared with the placebo group. Conclusion: NSPT plus 2% atorvastatin medicated dentifrice was more effective in improving clinical periodontal parameters than NSPT plus a placebo dentifrice.  相似文献   
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Steroids are drugs that have been used extensively in a variety of conditions. Although widely prescribed for their anti-inflammatory and immunosuppressive properties, glucocorticoids have several side effects, being hyperglycemia one of the most common and representative. In the present review, we discuss the main epidemiologic characteristics associated with steroid use, with emphasis on the identification of high risk populations. Additionally we present the pathophysiology of corticosteroid induced hyperglycemia as well as the pharmacokinetics and pharmacodynamics associated with steroid use. We propose a treatment strategy based on previous reports and the understanding of the mechanism of action of both, the different types of glucocorticoids and the treatment options, in both the ambulatory and the hospital setting. Finally, we present some of the recent scientific advances as well as some options for future use of glucocorticoids.  相似文献   
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Electrospun nanofibers are used for many applications due to their large surface area, mechanical properties, and bioactivity. Bacterial biofilms are the cause of numerous problems in biomedical devices and in the food industry. On the other hand, these bacterial biofilms can produce interesting metabolites. Hence, the objective of this study is to evaluate the efficiency of poly (Ɛ- caprolactone)/Curcumin (PCL/CUR) nanofibers to promote bacterial biofilm formation. These scaffolds were characterized by scanning electron microscopy (SEM), which showed homogeneous fibers with diameters between 441–557 nm; thermogravimetric analysis and differential scanning calorimetry (TGA and DSC) demonstrated high temperature resilience with degradation temperatures over >350 °C; FTIR and 1H-NMR serve as evidence of CUR incorporation in the PCL fibers. PCL/CUR scaffolds successfully promoted the formation of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa biofilms. These results will be valuable in the study of controlled harvesting of pathogenic biofilms as well as in metabolites production for biotechnological purposes.  相似文献   
58.
Different lines of evidence support an association between Epstein-Barr virus (EBV) and gastric cancer (GC). The main understood risk factor to develop GC is infection by Helicobacter pylori (H. pylori), which triggers a local inflammatory response critical for progression from gastritis to GC. The role of EBV in early inflammatory gastric lesions has been poorly studied. A recent study proposed a cutoff value of 2000 EBV particles to identify patients with increased chances of infection of the gastric epithelium, which may favor the inflammatory process. To better understand the role of EBV in cancer progression, we analyzed 75 samples of GC, 147 control samples of non-tumor gastric tissue derived from GC patients and 75 biopsies from patients with non-atrophic gastritis (NAG). A first-round PCR was used for EBV detection in tumor and non-tumor controls and a more sensitive nested PCR for gastritis samples; both PCRs had lower detection limits above the proposed cutoff value. With this strategy 10.67% of GC, 1.3% of non-tumor controls and 8% of gastritis samples were found positive. An EBER1 in situ hybridization showed EBV infection of epithelial cells in GC and in a third of NAG samples, while in the other NAGs infection was restricted to the mononuclear cell infiltrate. EBV-positive GCs were enriched in lace and cribriform patterns, while these rare patterns were not observed in EBV negative samples. Our results support a role for EBV in GC and early precursor lesions, either as directly oncogenic infecting epithelial cells or indirectly as an inflammatory trigger.  相似文献   
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