Assessment of body composition and sarcopenia in patients with esophageal cancer: a systematic review and meta-analysis.

There has recently been increased interest in the assessment of body composition in patients with esophageal cancer for the purpose of nutritional evaluation and prognostication. This systematic review and meta-analysis intends to summarize and critically evaluate the current literature concerning the assessment of body composition in patients with esophageal cancer and to assess its potential implication upon early and late outcomes. A systematic literature search (up to August, 2017) was conducted for studies describing the assessment of body composition in patients with esophageal and gastroesophageal junctional cancer. Meta-analysis of postoperative outcomes including long-term survival was performed using random effects models. Twenty-nine studies reported the assessment of body composition in 3193 patients. Methods used to assess body composition in patients with esophageal cancer included computerized tomography (n = 18 studies), bioelectrical impedance analysis (n = 10), and dual-energy X-ray absorptiometry (n = 1). Significant variability was observed in regard to study design and the criteria used to define individual parameters of body composition. Sarcopenic patients had a higher incidence of postoperative pulmonary complications (7 studies, OR 2.03, 95% CI 1.32-3.11, P = 0.001) after esophagectomy. Meta-analysis of six studies presenting long-term outcomes after esophagectomy identified significantly worse survival in patients who were sarcopenic (HR 1.70, 95% CI 1.33- 2.17, P < 0.0001). The assessment of body composition has the potential to become a clinically useful tool that could support decision-making in patients with esophageal cancer. Current evidence is however weakened by inconsistencies in methods of assessing and reporting body composition in this patient group.

The controversy of prostate screening.

Within the context of aging and ageism, this article evaluates current research on the benefits and risks of prostate cancer screening. Prostate cancer is a concern for many men because it often strikes in the prime of life. Prostate cancer is the most common form of cancer in American men and the second leading cause of cancer-related mortality after lung cancer. Although the disease can be cured if discovered early, it is a slow-growing malignancy that leads to an agonizing death if left untreated. Differential diagnosis often is complicated by comorbid conditions that are part of the normal aging process. Moreover, practitioners' judgment often is prejudiced by common aging misconceptions. Despite the benefits of early screening and detection, the benefits of screening initiatives remain controversial.

Indirect measurement of mitochondrial proton leak and its application.

In mitochondria, ATP synthesis is coupled to oxygen consumption by the proton electrochemical gradient established across the mitochondrial inner membrane in a process termed oxidative phosphorylation. It has long been known from stoichiometric studies that ATP synthesis is not perfectly coupled to oxygen consumption. The major inefficiency in the system is leakage of protons across the mitochondrial inner membrane driven by the proton electrochemical gradient. The kinetics of the proton leak can be determined indirectly, by measuring the oxygen consumption of mitochondria under non-phosphorylating conditions (plus oligomycin) as a function of the proton electrochemical gradient. This experimental system provides a convenient means to investigate inner membrane permeability to protons and the effect of factors that may effect that permeability. In this paper we review some results from our laboratory of indirect measurement of mitochondrial proton leak and how it has been applied to investigate the effect of aging, obesity and thyroid status on proton leak. The results show that (i) proton leak in isolated liver mitochondria is not significantly different in a comparison of young and old rats, in contrast (ii) there is an apparent increase in proton leak in in situ mitochondria in hepatocytes from old rats when compared to those from young rats, (iii) proton leak in neuronal mitochondria in situ in synaptosomes is not significantly different in young and old rats, (iv) proton leak is greater in isolated liver mitochondria from ob/ob mice compared to lean controls, (v) acute leptin (OB protein) administration restores the increased leak rate in isolated liver mitochondria from ob/ob mice to that of lean controls, (vi) administration of thyroid hormone (T3) increases proton leak in rat muscle mitochondria, and (vii) proton leak in muscle mitochondria is insensitive to the presence of GDP. It is proposed that the experimental system described here for measuring proton leak, is an ideal functional assay for determining whether the novel uncoupling proteins increase inner membrane permeability to protons.