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Ameloblastoma is a locally aggressive neoplasm with a poorly understood pathogenesis. Therefore, the aim of this study is to investigate whether COX-2 expression is associated with ameloblastoma microvascular density (MVD) and with tumor aggressiveness. Sixty-three cases of primary ameloblastomas arranged in tissue microarray were submitted to immunohistochemistry against cyclooxigenase-2 (COX-2) and CD34. Clinicopathological parameters regarding sex, age, tumour size, tumour duration, tumour location, treatment, recurrences, radiographic features, vestibular/lingual and basal cortical disruption and follow-up data were obtained from patients’ medical records and correlated with the proteins expression. The results on BRAF-V600E expression were obtained from our previous study and correlated with COX-2 and CD34 expressions. Log-rank univariate analysis and multivariate Cox regression model were done to investigate the prognostic potential of the molecular markers. Twenty-eight cases (44.4%) exhibited cytoplasmic positivity for COX-2, predominantly in the columnar peripheral cells, with a mean MVD of 2.2 vessels/mm2. COX-2 was significantly associated with recurrences (p?<?0.001) and BRAF-V600E expression (p?<?0.001), whereas lower MVD was associated with the use of conservative therapy (p?=?0.004). Using univariate and multivariate analyses, COX-2 was significantly associated with a lower 5-year disease-free survival (DFS) rate (p?<?0.001 and p?=?0.012, respectively), but not with a higher MVD (p?=?0.68). In conclusion, COX-2 expression in ameloblastomas is not associated with MVD, but it is significantly associated with recurrences and with a lower DFS.  相似文献   
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Angiotensin II inhibits insulin-induced activation of phosphatidylinositol 3-kinase through a mechanism, at least in part, dependent on serine phosphorylation of the insulin receptor and insulin receptor substrates (IRS)-1/2. Recent evidence shows that suppressor of cytokine signaling-3 (SOCS-3) is induced by insulin and angiotensin II and participates in the negative control of further stimulation of each of these signaling systems independently. In the present study, we evaluated the interaction of angiotensin II-induced SOCS-3 with the insulin signaling pathway in the heart of living rats. A single iv dose of angiotensin II promotes a significant increase of SOCS-3 in heart, an effect that lasts up to 180 min. Once induced, SOCS-3 interacts with the insulin receptor, JAK-2, IRS-1, and IRS-2. The inhibition of SOCS-3 expression by a phosphorthioate-modified antisense oligonucleotide partially restores angiotensin II-induced inhibition of insulin-induced insulin receptor, IRS-1 and IRS-2 tyrosine phosphorylation, and IRS-1 and IRS-2 association with p85-phosphatidylinositol 3-kinase and [Ser473] phosphorylation of Akt. Moreover, the inhibition of SOCS-3 expression partially reverses angiotensin II-induced inhibition of insulin-stimulated glucose transporter-4 translocation to the cell membrane. These results are reproduced in isolated cardiomyocytes. Thus, SOCS-3 participates, as a late event, in the negative cross-talk between angiotensin II and insulin, producing an inhibitory effect on insulin-induced glucose transporter-4 translocation.  相似文献   
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Objectives Hypovitaminosis D (HD) and secondary hyperparathyroidism (SHP) are common in elders, and many factors could contribute to them. The objectives of this study were to estimate the prevalence of HD, SHP, and its associated factors, in individuals living in nonprofit homes for elders in south Brazil. Design Cross-sectional study. Methods Serum 25-hydroxyvitamin D 25(OH)D, intact parathyroid hormone (PTH), total calcium, phosphorus, alkaline phosphatase, magnesium, creatinine, and albumin levels were measured in late spring, November, 2005. The presence of factors potentially related with HD and SHP—age, sex, weight, height, skin phototype, sun exposure, exercise, smoking, use of ≤5 medications or diuretics or alcohol, and daily calcium ingestion. Results 102 subjects age 77.8 ± 9.0 were included in the study. HD was found in 85.7% and SHP in 53% of the subjects. The estimated daily calcium ingestion was 720 mg. There was no association between serum 25(OH)D levels and any of the risk factors evaluated. Serum 25(OH)D levels were correlated with serum PTH (r = −0.358, P = 0.000), calcium (r = 0.306, P = 0.002), and albumin (r = 0.253, P = 0.011) levels. In univariate analysis, SHP was positively associated with age (P = 0.006), and female sex (0.007); and negatively associated with sunlight exposure (P = 0.020), GFR (P = 0.000), Ln25(OH)D (P = 0.002), and total serum calcium (P = 0.024). After multivariate model adjustment, age [OR 1.09 (CI 1.01–1.18); P = 0.024], Ln25(OH)D [OR 0.92 (CI 0.08–0.74); P = 0.013], GFR [OR 0.96 (CI 0.92–0.99); P = 0.013], and hydrochlorothiazide treatment [OR 7.63 (CI 1.67–34.9); P = 0.008] were independently associated with SHP. Conclusions HD and SHP are highly prevalent in elders living in old-age homes. No associations were established between common risk factors and low serum levels of 25(OH)D levels; however, SHP was independently related with age, 25(OH)D, GFR, and hydrochlorothiazide use.  相似文献   
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Necrotizing sarcoid granulomatosis (NSG) is a rare entity mainly characterized by a prominent granulomatous vasculitis affecting middle-aged or old individuals and with a favorable prognosis. Although many believe it is a variant of sarcoidosis, the proper classification is still a matter of debate as some of its features are found in sarcoidosis but also in Churg-Strauss syndrome, Wegener's disease and hypersensitivity pneumonitis. In this paper, we described for the first time a case of NSG in a family with several cases of sarcoidosis, reinforcing the relationship between NSG and sarcoidosis. Additional interesting findings were the young age of the patient (15 years old), the symptoms limited to the respiratory tract (uncommon when NSG affects youngsters) and the increase in serologic markers of autoimmune disease. Though complete criteria for autoimmune disease were not present, systemic lupus erythematosus and Sjogren's syndrome are possible candidates. As sarcoidosis is described to be associated with several autoimmune diseases, this finding is an additional suggestion of the relationship between both entities.  相似文献   
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Background Residual plaque burden after coronary stenting may be visualized by use of intravascular ultrasound. Determinants and implications of residual atherosclerotic plaque burden after coronary stenting are not well established. In particular, the implications of residual plaque burden, after adjusting for confounding factors, are still unknown. Methods Sixty-two consecutive patients (age 56 ± 9 years) undergoing coronary stenting under intravascular ultrasound imaging guidance were prospectively studied. A total of 616 slices were analyzed (every 2 mm of stent length) from motorized pull-back recordings. Residual plaque burden was calculated as residual plaque/vessel area × 100. Results In 565 slices (89%), both residual plaque area and stent area could be measured. Mean residual plaque burden was 46.5% ± 6%. By use of multiple regression analysis, lesion plaque area and reference segment plaque burden were identified as independent predictors of residual plaque burden after stenting. In addition, a significant correlation was found between residual plaque burden and most relevant angiographic parameters at follow-up (including minimal lumen diameter, percent diameter stenosis, and loss index), which persisted after adjustment. Furthermore, stents with a residual plaque burden ≥46% had higher a restenosis rate (relative risk [RR] 4.4, 95% CI 1.09-18.2, P = .03). On logistic regression analysis, residual plaque burden (RR 4.8, 95% CI 4.1-5.6, P = .01) and diabetes (RR 4.3, 95% CI 3.6-5.1, P = .03) emerged as the only independent predictors of restenosis. Conclusions The amount of residual plaque burden after coronary stenting plays an independent role on the late angiographic outcome of these patients. (Am Heart J 2003;145:254-61.)  相似文献   
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We have investigated the effect of therapy forHelicobacter pylori gastritis on serum concentrations of pepsinogen I and II in 43 patients. In the 22 patients in whom therapy resulted in dramatic decrease in gastritis scores and in clearance of the bacteria, there was a highly significant (P=0.0001) fall in mean serum pepsinogen II from 13.3±0.8 to 7.9±0.7 μg/liter, and a less pronounced fall in pepsinogen I from 89.0±5.9 to 78.5±0.4 μg/liter (P=0.01). These changes resulted in a significant (P=0.01) increase in the pepsinogen I/II ratio. In contrast, nonsignificant declines of 3.5% and 11.6% were observed in mean pepsinogen I and II levels in the 21 patients whose gastritis failed to resolve histologically and whose infection did not clear. These findings suggest that serum pepsinogen levels, especially pepsinogen II, are a new tool that may be found to be clinically useful in evaluation of treatment outcome in patients withH. pylori-associated gastritis.  相似文献   
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Background

The Activity Measure for Post-Acute Care was developed to evaluate the limitations of activities of adult individuals with different health conditions.

Objectives

To translate and cultural adapt the Activity Measure for Post-Acute Care short forms for outpatients into Portuguese–Brazilian, to verify the comprehension of the items and categories of the responses by users of the rehabilitation services and to analyze the reliability indices of the instrument.

Methods

Translation and back-translation were conducted by two independent teams. Cognitive interviews (n = 2) evaluated the comprehension of the translated version among patients. Item reliability and consistency was also investigated.

Results

There was conceptual equivalence between the translated and original versions. For some items, the information was modified in order to attend to the measurement units used in Brazil. Comparative analyses of the translated versions chose the most appropriate term to capture the English content. The few discrepancies identified in the back-translation were solved by consensus. The cognitive interviews detected few comprehension problems, which were solved by means of repetition of the item statement and use of examples to clarify the specificity of the information. The final translated short forms of the instrument showed excellent test-retest reliability and inter-examiner reliability indices, as well as high internal consistency.

Conclusion

The Portuguese version of the Activity Measure for Post-Acute Care short forms will provide Brazilian clinicians and researchers with an up-to-date instrument for the evaluation of functioning of adults with various clinical conditions who attend outpatient rehabilitation settings.  相似文献   
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