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Background and Purpose: The rod outer segments (OS) of the retina are specialized organelles where phototransduction takes place. The mitochondrial electron transport complexes I-IV, cytochrome c and Fo F1 -ATP synthase are functionally expressed in the OS disks. Here, we have studied the effect of some polyphenolic compounds acting as inhibitors of mitochondrial ATPase/synthase activity on the OS ectopic Fo F1 - ATP synthase. The mechanism of apoptosis in the OS was also investigated studying the expression of cytochrome c, caspase 9 and 3 and Apaf-1., Experimental Approach: We prepared OS from fresh bovine retinae. Semi-quantitative Western blotting, confocal and electron microscopy, and cytofluorimetry were used along with biochemical analyses such as oximetry, ATP synthesis and hydrolysis., Key Results: Resveratrol and curcumin plus piperine inhibited ATP synthesis and oxygen consumption in the OS. Epigallocatechin gallate and quercetin inhibited ATP hydrolysis and oxygen consumption in the OS. Malondialdehyde and hydrogen peroxide were produced in respiring OS in the presence of substrates. Cytochrome c was located inside the disk membranes. Procaspase 9 and 3, as well as Apaf-1 were expressed in the OS., Conclusions and Implications: These polyphenolic phytochemicals modulated the Fo F1 -ATP synthase activity of the the OS reducing production of reactive oxygen intermediates by the OS ectopic electron transport chain. Polyphenols decrease membrane peroxidation and cytochrome c release from disks, preventing the induction of caspase-dependent apoptosis in the OS Such effects are relevant in the design of protection against functional impairment of the OS following oxidative stress from exposure to intense illumination., (© 2015 The British Pharmacological Society.)

Objectives: The diagnostic performance of transthoracic focused cardiac ultrasound (FoCUS) performed by emergency physicians (EP) to estimate ascending aorta dimensions in the acute setting has not been prospectively studied. The diagnostic accuracy and the interobserver variability of EP-performed FoCUS were investigated to estimate thoracic aortic dilation and aneurysm compared with the results of computed tomography angiography (CTA)., Methods: This was a prospective single-center cohort study of a convenience sample of patients who underwent CTA in the emergency department for suspected aortic pathology. FoCUS was performed before CTA, and the maximum ascending aorta diameter evaluated in parasternal long-axis view. Aorta diameter < 40 mm by visual estimation or by diameter measurement was considered normal. Measurements were recorded in all patients with aorta diameter ≥ 40 mm. Diagnostic accuracy of FoCUS for detection of aortic dilation (diameter ≥ 40 mm) and aneurysm (diameter ≥ 45 mm) were calculated considering the CTA result as reference standard. In a subgroup of patients, a second EP-sonographer performed FoCUS to evaluate interobserver agreement for the diagnosis of ascending aorta dilation., Results: A total of 140 patients were enrolled in the study. Ascending aorta dilation and aneurysm were detected with FoCUS in 50 (35.7%) and in 27 (17.8%) patients, respectively. Sensitivity and specificity of FoCUS were 78.6% (95% confidence interval [CI] = 65.6% to 88.4%) and 92.9% (95% CI = 85.1% to 97.3%), respectively, for ascending aorta dilation and 64.7% (95% CI = 46.5% to 80.2%) and 95.3% (95% CI = 89.3% to 98.4%), respectively, for ascending aorta aneurysm. Interobserver agreement of FoCUS was k = 0.82., Conclusions: FoCUS performed by EP is specific for ascending aorta dilation and aneurysm when compared to CTA and appears a reproducible technique., (© 2015 by the Society for Academic Emergency Medicine.)

Background: Adjuvant chemotherapy for colorectal carcinoma was found to improve survival of patients with American Joint Committee on Cancer/International Union Against Cancer Stage III disease. The usefulness of chemotherapy in patients with Stage II disease continues to be debated, and it is likely that only those patients with a poor prognosis should receive adjuvant chemotherapy. Biologic prognostic factors may allow further insight into the optimal treatment strategy for patients with Stage II or earlier disease. In this study the prognostic role of S-phase fraction (SPF) determined by flow cytometry was assessed in patients with Stage I-II colorectal carcinoma., Methods: Specimens of surgically resected colorectal carcinoma were examined for SPF by flow cytometric DNA analysis. Consecutive patients referred to the study institution were considered eligible for this study. The main inclusion criteria were a Stage I-II tumor together with sufficient tumor material and adequate follow-up information. For each stage of disease, SPF data were associated with the recurrence rate and the disease free survival (DFS)., Results: Analysis was performed on 167 patients (65 with Stage I disease and 102 with Stage II disease). Among Stage I patients, SPF was high in 20 patients and low in 45 patients. In Stage II patients, there were 36 patients with low SPF and 66 patients with high SPF. In both stages, the recurrence rate and DFS were significantly worse for the subgroups of patients with high SPF., Conclusions: SPF has revealed prognostic differences among patients with surgically resected Stage I-II colorectal carcinoma. These data should be considered for planning future trials in the adjuvant setting because patients with high SPF may benefit from adjuvant chemotherapy.