Study of the Effect of Renal Transplantation on Methacholine Challenge Test in Patients With End-Stage Renal Failure in Shahid Doctor Labafinejad Hospital in Tehran, Iran

Pulmonary complications are common in patients with chronic renal failure (CRF). The objective of this study was determine the effect of renal transplantation on pulmonary function, using a methacholine challenge test. This interventional study included 14 CRF patients on maintenance dialysis who underwent serial spirometry and astography before and after renal transplantation. None of them was known to have clinically important pulmonary or heart disease. The results of spirometry, astography, echocardiography, and chest X-ray were normal. Five patients were men and all others were women. The overall age range was 15 to 45 years (mean age = 28.6 ± 10.9). For every patient four times astography was done. The mean values of spirometric and astography indices before and after renal transplantation were within normal limit. But by repeated measure analysis of variance, the results actually showed improved airway responsiveness (although within normal limits). The most common pathological lung condition in CRF is pulmonary edema, usually due to a combination of fluid overload and abnormal permeability of the pulmonary microcirculation. However, our patients had no symptomatic pulmonary edema, but minor degrees of fluid retention are virtually impossible to detect clinically and could not be excluded. Therefore, it seems that disappearance of subclinical pulmonary edema was the likeliest cause of an increase in minimum dose of methacholine, and therefore improvement in airway responsiveness after renal transplantation. © 2007 Elsevier Inc. All rights reserved

The prevalence of left ventricular heart failure in chronic obstructive pulmonary disease patients: Brief report

Background: Chronic obstructive pulmonary disease (COPD) and heart failure are prevalent comorbidities affecting a vast proportion of the world population, responsible for significant morbidity and mortality, their coexistence is more frequent than previously recognized that poses important diagnostic and therapeutic challenges. We intend to determine the prevalence of concomitant left ventricular dysfunction in COPD patients. Methods: We performed a cross-sectional study in patients who had referred to Firuzgar University Hospital in Tehran from March 2011 to March 2013 in period of 2 years. All participants were compatible for including and excluding criteria�s. In all cases of COPD, pulmonary function test was done; also Echocardiography was performed as the diagnostic assessment of heart failure. Results: Out of 74 participants there was 56(75.7) male and 18(24.3) female with the mean age of 67.7±12.9 (SD), the prevalence of left ventricular systolic dysfunction (LVSD) was 25.70, also the prevalence of left ventricular diastolic dysfunction (LVDD) was 74.60 among 71 patients. The prevalence of LVSD in patients with and without history of coronary artery disease (CAD) was 33.30 and 15.60 respectively. The prevalence of LVDD was 85.40 in patient with history of CAD and 60 in patients without it. The presence of ventricular dysfunction (neither systolic nor diastolic) in COPD patients was not statistically associated with presence of CAD or the intensity of underlying COPD disease. Conclusion: Knowledge about the prevalence of concomitant left side heart failure in COPD patients is limited, but it seems the presence is rather common, so more attention should be paid to coexistence of ventricular dysfunction in COPD patients disregarding presence of CAD or COPD intensity in clinical practice. © 2015, Tehran University of Medical Sciences. All rights reserved

Model-Based Predictive Control Scheme for Cost Optimization and Balancing Services for Supermarket Refrigeration Systems

A new formulation of model predictive control for supermarket refrigeration systems is proposed to facilitate the regulatory power services as well as energy cost optimization of such systems in the smart grid. Nonlinear dynamics existed in large-scale refrigeration plants challenges the predictive control design. It is however shown that taking into account the knowledge of different time scales in the dynamical subsystems makes possible a linear formulation of a centralized predictive controller. A realistic scenario of regulatory power services in the smart grid is considered and formulated in the same objective as of cost optimization one. A simulation benchmark validated against real data and including significant dynamics of the system are employed to show the effectiveness of the proposed control scheme