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The aging suppressor gene klotho encodes a single-pass transmembrane protein klotho that in mice is known to extend life span when overexpressed and to resemble accelerated aging, with skeletal muscle atrophy and decreased bone mineral density, when expression is disrupted. We sought to examine the relationship between plasma klotho and disability in activities of daily living (ADL) in older community-dwelling adults. In a cross-sectional study, plasma klotho was measured in a population-based sample of 802 adults, ≥ 65 years, who participated in the "Invecchiare in Chianti" (Aging in the Chianti Area) (InCHIANTI) study in Tuscany, Italy. The overall proportion of adults with ADL disability was 11.9%. Mean (standard deviation) klotho concentrations were 689 (238) pg/mL. From the lowest to the highest tertile of plasma klotho, 16.1%, 9.7%, and 5.6% of participants, respectively, had ADL disability (p=0.0004). Plasma klotho, per 1 standard deviation increase, was associated with ADL disability (odds ratio=0.57, 95% confidence interval 0.35-0.93, p=0.02) in a multivariate logistic regression model adjusting for age, education, cognition, physical activity, physical performance, total cholesterol, alcohol and tobacco use, and chronic diseases. Low plasma klotho concentrations were independently associated with ADL disability among older community-dwelling men and women.  相似文献   
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Objectives

To assess the accuracy of intra-rectal coil magnetic resonance imaging (ER-MRI) for staging early prostate cancer (EPC).

Materials and methods

ER-MRI was performed with the Magnetom Symphony 1.5 Tesla system. ER-MRI and pathology findings were statistically correlated.

Results

One hundred and fifty-four consecutive patients underwent radical prostatectomy (RRP) for EPC (cT1c-2 Nx M0). An average age was 66, mean PSA 11.04 µg/L (median 7.33 µg/L) and mean pathologic Gleason score 6. Pathology detected 97 out of 154 patients (63 %) as EPC and 57 cases (37 %) as extra-prostate extension (EPED) (pT3) with extra-capsular extension (ECE) (pT3a) in 41 (27 %) and seminal vesicle invasion (SVI) (pT3b) in 16 (10 %). ER-MRI staged 100 patients (65 %) as cT2 and 54 (35 %) as EPED with ECE in 37 cases (24 %) and SVI in 17 (11 %). ER-MRI sensitivity, specificity, positive predictive value, negative predictive value, overall accuracy resulted respectively 0.78, 0.96, 0.86, 0.92, 0.91 for ECE as well as 0.88, 0.98, 0.82, 0.99 and 0.97 for SVI.

Conclusion

ER-MRI was effective in detecting preoperative EPC under-staging. In the next future, multi-parametric 3-Tesla ER-MRI will be the procedure for diagnosing, staging and following-up prostate cancer patients.  相似文献   
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Background

Colorectal cancer (CRC) is a leading cause of cancer morbidity and mortality. People at higher risk are those individuals with a family history of CRC and familial adenomatous polyposis. Prevention and screening are two milestones for this disease. The aim of this study is to evaluate the chemopreventive role of non-steroidal anti-inflammatory drugs (NSAIDs), including aspirin and cyclooxygenase 2 inhibitors, some micronutrients (folic acid, calcium, selenium, antioxidants) and probiotics.

Discussion

The studies on aspiring reported promising results, but it is debatable whether aspirin should be used as chemoprevention, because of its side effects and because of poor efficacy evident in subjects at high risk. Similar results were reported for other non-aspirin NSAIDs, such as sulindac and celecoxib, which the potential adverse effects limit their use. Selenium role in prevention of various types of cancer as well as in colon adenomas are often inconclusive or controversial. Several studies suggested that calcium may have a possible chemopreventive effect on colon adenomas and CRC, although contrasting results are reported for the latter. A recent meta-analysis including 13 randomized trial suggested that folic acid supplementation had not a chemiopreventive action on CRC. Several studies investigated the association between antioxidants, administered alone or in combination, and CRC risk, both among general and at risk population, but only few of them supported statistically significant results.

Conclusion

The results of this literature review showed an unclear role in CRC prevention of both pharmacological and dietary intervention. Despite several options are available to prevent colon cancer, it is challenging to identify a correct strategy to prevent CRC through pharmacological and dietary intervention due to the long latency of cancer promotion and development. Since some of the drugs investigated may have uncertain individual effects, it can be suggested to potentiate such effects by adding them together.
  相似文献   
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Background

Overall cancer incidence rates decreased in the most recent time period in both men and women, largely due to improvements in surgical therapeutic approaches (tertiary prevention) and screening programs (secondary prevention), but differences in cancer incidence and survival according to socioeconomic status are documented worldwide. Health risk behaviors, defined as habits or practices that increase an individual’s likelihood of harmful health outcomes, are thought to mediate such inequalities.

Discussion

Obesity has been related with increased cancer incidence and mortality due to imbalance of leptin and adiponectin which are connected to activation of PI3K, MAPK, and STAT3 pathways and decreasing insulin/insulin-like growth factor (IGF)-1 and mTOR signaling via activation of 5 AMP-activated protein kinase (AMPK), respectively. Physical activity has been associated to prevent cancer by the aforementioned obesity-related mechanisms, but also increasing level of circulating vitamin D, which has been related to lower risk of several cancers, and increasing prostaglandin F2a and reducing prostaglandin E2, which are both related with cancer prevention and promotion, respectively. A large number of different substances may induce themselves a direct cytotoxicity and mutagenic action on cells by smoking, whereas alcohol promote immune suppression, the delay of DNA repair, inhibition of the detoxification of carcinogens, the production of acetaldehyde, and the contribution to abnormal DNA methylation. The combined smoking and alcohol drinking habits have been shown to increase cancer risk by smoke action of increasing the acetaldehyde burden following alcohol consumption and alcohol action of enhancing the activation of various procarcinogens contained in tobacco smoke.

Conclusions

Interventions at the social level may be done to increase awareness about cancer risks and promote changing in unhealthy behaviors.
  相似文献   
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