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21.

Purpose

Obese men have been reported to have lower serum PSA values relative to normal-weight men in population-based studies, screening cohorts, and in men with prostate cancer (CaP) treated with surgery. There are concerns that PSA may be less accurate in detecting prostate cancer in men with increased body mass index (BMI). We determine whether the diagnostic potential of PSA is negatively influenced by obesity by comparing its operating characteristics across BMI categories among men undergoing prostate biopsy.

Methods

Demographic, clinical, and histopathological data on 917 men who underwent trans-rectal ultrasound-guided prostate needle biopsy from 2002 to 2010 at a University hospital in Italy were used in the study. Men were categorized for BMI as follows: <25 kg/m2 (normal weight), 25–29.9 kg/m2 (overweight), and ≥30 kg/m2 (obese). Receiver operator characteristics (ROC) curves were used to assess PSA accuracy for predicting prostate cancer overall and then stratified according to digital rectal examination (DRE) findings using the area under the ROC curve (AUC).

Results

The obesity rate of the study cohort was 21 %. There was no statistically significant difference in the overall AUCs of PSA for predicting CaP among normal-weight (AUC = 0.56), overweight (AUC = 0.60), and obese men (AUC = 0.60; p = 0.68) in either DRE-positive or negative men.

Conclusions

In a cohort of Italian men undergoing prostate biopsy, the performance accuracy of PSA as a predictor of CaP is not significantly altered by BMI. Obesity does not negatively impact the overall ability of PSA to discriminate between CaP and benign conditions.  相似文献   
22.
ObjectivesTo analyze clinicopathological features and survival of surgically treated patients with renal cell carcinoma (RCC)≥80 years of age in comparison with patients between the ages of 60 and 70 years.Materials and methodsThe data for 2,516 patients with a median follow-up of 57 months were retrieved from a multinational database (Collaborative Research on Renal Neoplasms Association [CORONA]), including data for 6,234 consecutive patients with RCC after radical or partial nephrectomy. Comparative analysis of clinicopathological features of 241 octogenarians (3.9% of the database) and 2,275 reference patients between the ages of 60 and 70 years (36.5%) was performed. Multivariable regression analysis adjusted for competing risks was applied to identify the effect of advanced age on cancer-specific mortality (CSM) and other-cause mortality (OCM). Furthermore, instrumental variable analysis was employed to reduce residual confounding by unmeasured parameters.ResultsSignificantly more women were present (50% vs. 40%, P = 0.004), and significantly less often nephron-sparing surgery was performed in octogenarians compared with the reference group (11% vs. 20%, P<0.001). Although median tumor size and stages did not significantly defer, older patients less often had advanced or metastatic disease (N+/M1) (4.6% vs. 9.6%, P = 0.009). On multivariable analysis, higher CSM (hazard ratio = 1.48, P = 0.042) and OCM rates (hazard ratio = 4.32, P<0.001) were detectable in octogenarians (c-indices = 0.85 and 0.72, respectively). Integration of the variable age group in multivariable models significantly increased the predictive accuracy regarding OCM (6%, P<0.001), but not for CSM. Limitations are based on the retrospective study design.ConclusionsOctogenarian patients with RCC significantly differ in clinical features and display significantly higher CSM and OCM rates in comparison with their younger counterparts.  相似文献   
23.
ObjectivesTo test the hypothesis that patients with widespread high grade prostatic intra epithelial neoplasia (wHGPIN) and metabolic syndrome (MetS) are at a higher risk of prostate cancer (PCa) at a repeat biopsy.Methods and MaterialsWe prospectively evaluated 161 patients submitted from December 2004 to December 2011 to prostate rebiopsy after a initial diagnosis of HGPIN in a tertiary academic center. A 12 core biopsy template was used for all the biopsies. Rebiopsy was performed six months after the initial biopsy independently from PSA level and the DRE finding. wHGPIN was defined as≥4 biopsy cores involved. MetS was defined according to the National Cholesterol Education Program’s Adult Treatment Panel III criteria.ResultsOverall, 64 patients (39.7%) presented wHGPIN and 97 isolated HGPIN (60.3%). MetS was found in 63 patients, 39.1% of the whole population. Out of them 16 (25.3%) and 47 (74.7%) patients had a diagnosis of isolated and wHGPIN (P = 0.001). PCa detection rate at repeat biopsy was significantly higher in patients with MetS and wHGPIN than in those with wHGPIN and no MetS (57.4% Vs 23.5%; P = 0.016). A logistic regression model confirmed that wHGPIN and MetS are independent risk factors of prostate cancer diagnosis (respectively: Odds ratio (OR) = 4.187, 95%CI: 1.65–10.57 p = 0.002 and OR=3.603, 95%CI: 1.41-9.19, p = 0.007).ConclusionPatients with MetS and wHGPIN are at a higher risk of PCa, therefore performing a new prostate biopsy in those patients should be recommended.  相似文献   
24.
ObjectivesTo explore the association between serum levels of 17-β-estradiol (17BE) and prostate cancer (PCa) risk in men undergoing prostate biopsy.Methods and materialsBetween 2006 and 2012, we prospectively enrolled 894 patients, with no history of PCa, undergoing prostate biopsy. Before biopsy was performed, general data, digital rectal examination (DRE), body mass index, 17BE, and prostate-specific antigen (PSA) were recorded. The risk of detecting cancer and high-grade cancer was assessed as a function of 17BE using crude and adjusted logistic regressions.ResultsSerum levels of 17BE were not associated with an increased risk of PCa or high-grade disease. Age (odds ratio [OR] 1.05; 95% confidence interval [CI]: 1.03–1.07; P = 0.000), DRE(OR 2.81; 95% CI: 1.98–4.00; P = 0.000), and PSA(OR 1.07; 95% CI: 1.04–1.10; P = 0.000) were found to be independent predictors of PCa risk. Age (OR 1.05; 95% CI: 1.01–1.09; P = 0.007), DRE (OR 3.04; 95% CI: 1.79–5.17; P = 0.000), body mass index (OR 1.07; 95% CI: 1.01–1.150; P = 0.040), and PSA (OR 1.08; 95% CI: 1.03–1.12; P = 0.000) were found to be independent predictors of high-grade disease.ConclusionIn our cohort of patients, serum levels of 17BE are not predictive of PCa or high-grade disease. In patients at risk of PCa, 17BE should not be considered a reliable marker to predict poorly differentiated PCa in the setting of initial prostate biopsy.  相似文献   
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Personality traits are multidimensional traits comprising cognitive, emotional, and behavioral characteristics, and a wide array of cerebral structures mediate individual variability. Differences in personality traits covary with brain morphometry in specific brain regions, and neuroimaging studies showed structural or functional abnormalities of cerebellum in subjects with personality disorders, suggesting a cerebellar role in affective processing and an effect on personality characteristics. To test the hypothesis that cerebellar [white matter (WM) and cortex] volumes are correlated with scores obtained in the four temperamental scales of the Temperament and Character Inventory (TCI) by Cloninger, a total of 125 healthy participants aged 18–67 years of both genders (males = 52) completed the TCI and underwent magnetic resonance imaging. The scores obtained in each temperamental scale were associated with the volumes of cerebellar WM and cortex of right and left hemispheres separately by using linear regression analyses. In line with our hypothesis, novelty seeking (NS) scores were positively associated with WM and cortex cerebellar volumes. Harm avoidance (HA) scores were negatively associated with WM and cortex cerebellar volumes. The range of individual differences in NS and HA scores reflects the range of variances of cerebellar volumes. The present data indicating a cerebellar substrate for some personality traits extend the relationship between personality and brain areas to a structure up to now thought to be involved mainly in motor and cognitive functions, much less in emotional processes and even less in personality individual differences. Hum Brain Mapp 35:285–296, 2014. © 2012 Wiley Periodicals, Inc.  相似文献   
27.
Novelty Seeking (NS) and Harm Avoidance (HA) temperamental traits are related to approaching or avoiding motivational circuits relying on the integrity and functionality of distributed brain areas implicated in arousal and action. The present study verified whether and how macro- and micro-structural variations of basal ganglia are correlated with scores obtained in the NS and HA temperamental scales of the Temperament and Character Inventory by Cloninger. To this aim, 125 healthy adults aged 18–67 years of both sexes completed the Temperament and Character Inventory and underwent a high-resolution T1-weighted magnetic resonance imaging and a diffusion tensor imaging using a 3T scanner. The scores obtained in the temperamental scales were associated with volumes, mean diffusivity and fractional anisotropy measures of basal ganglia of both hemispheres separately, by using linear regression analyses. We found increased bilateral caudate and pallidum volumes associated with higher NS scores, as well as increased mean diffusivity in the bilateral putamen associated with higher HA scores. Macro- and micro-structural variations of basal ganglia regions contribute to explain the biological variance associated with NS or HA personality phenotype. The present findings evidencing some brain-temperament relationships highlight the importance of obtaining macro- and micro-structural measures in relation to individual differences.  相似文献   
28.
The authors investigated the role of resveratrol (RV), a natural poliphenolic molecule with several biological activities, in transforming growth factor-β (TGF-β)-induced proliferation and differentiation of ex vivo human pulmonary fibroblasts into myofibroblasts. The effects of RV treatment were evaluated by analyzing TGF-β-induced α-smooth muscle actin (α-SMA) expression and collagen production, as well as cell proliferation of both normal and idiopathic pulmonary fibrosis (IPF) lung fibroblasts. Results demonstrate that RV inhibits TGF-β-induced cell proliferation of both normal and pathological lung fibroblasts, attenuates α-SMA expression at both the mRNA and protein levels, and also inhibits intracellular collagen deposition. In order to understand the molecular mechanisms, the authors also investigated the effects of RV treatment on signaling pathways involved in TGF-β-induced fibrosis. The authors show that RV inhibited TGF-β-induced phosphorylation of both extracellular signal-regulated kinases (ERK1/2) and the serine/threonine kinase, Akt. Moreover, RV treatment blocked the TGF-β-induced decrease in phosphatase and tensin homolog (PTEN) expression levels.  相似文献   
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