Effect of selective and nonselective β-blockers on resting energy production rate and total body substrate utilization in chronic heart failure

Background: In chronic heart failure (CHF) β-blockers reduce myocardial oxygen consumption and improve myocardial efficiency by shifting myocardial substrate utilization from increased free fatty acid oxidation to increased glucose oxidation. The effect of selective and nonselective β-blockers on total body resting energy production rate (EPR) and substrate utilization is not known. Methods: Twenty-six noncachectic patients with moderately severe heart failure (New York Heart Association class II or III, left ventricular ejection fraction < 0.40) were treated with carvedilol (37.5 ± 13.5 mg/12 h) or bisoprolol (5.4 ± 3.0 mg/d) for 6 months. Indirect calorimetry was performed before and after 6 months of treatment. Results: Resting EPR was decreased in carvedilol (5.021 ± 0.803 to 4.552 ± 0.615 kJ/min, P < .001) and bisoprolol group (5.230 ± 0.828 to 4.978 ± 0.640 kJ/min, P < .05; nonsignificant difference between groups). Lipid oxidation rate decreased in carvedilol and remained unchanged in bisoprolol group (2.4 ± 1.4 to 1.5 ± 0.9 mg m²/kg min versus 2.7 ± 1.1 to 2.5 ± 1.1 mg m²/kg min, P < .05). Glucose oxidation rate was increased only in carvedilol (2.6 ± 1.4 to 4.4 ± 1.6 mg m²/kg min, P < .05), but did not change in bisoprolol group. Conclusions: Both selective and nonselective β-blockers reduce total body resting EPR in noncachectic CHF patients. Carvedilol compared to bisoprolol shifts total body substrate utilization from lipid to glucose oxidation.     

Role of sex in post-transplant diabetes mellitus development: Are men and women equal?

Introduction

Sex differences are defined as biology-linked differences between women and men that occur through the sex chromosomes and their effects on organ systems.

Light transmittance and polymerization kinetics of amorphous calcium phosphate composites

Clinical Oral Investigations - This study investigated light transmittance and polymerization kinetics of experimental remineralizing composite materials based on amorphous calcium phosphate (ACP),...     

The Waist Width of Skis Influences the Kinematics of the Knee Joint in Alpine Skiing

Recently alpine skis with a wider waist width, which medially shifts the contact between the ski edge and the snow while turning, have appeared on the market. The aim of this study was to determine the knee joint kinematics during turning while using skis of different waist widths (65mm, 88mm, 110mm). Six highly skilled skiers performed ten turns on a predefined course (similar to a giant slalom course). The relation of femur and tibia in the sagital, frontal and coronal planes was captured by using an inertial motion capture suit, and Global Navigation Satellite System was used to determine the skiers’ trajectories. With respect of the outer ski the knee joint flexion, internal rotation and abduction significantly decreased with the increase of the ski waist width for the greatest part of the ski turn. The greatest abduction with the narrow ski and the greatest external rotation (lowest internal rotation) with the wide ski are probably the reflection of two different strategies of coping the biomechanical requirements in the ski turn. These changes in knee kinematics were most probably due to an active adaptation of the skier to the changed biomechanical conditions using wider skis. The results indicated that using skis with large waist widths on hard, frozen surfaces could bring the knee joint unfavorably closer to the end of the range of motion in transversal and frontal planes as well as potentially increasing the risk of degenerative knee injuries.

Key points

• The change in the skis’ waist width caused a change in the knee joint movement strategies, which had a tendency to adapt the skier to different biomechanical conditions.
• The use of wider skis or, in particular, skis with a large waist width, on a hard or frozen surface, could unfavourably bring the knee joint closer to the end of range of motion in transversal and frontal planes as well as may potentially increase the risk of degenerative knee injuries.
• The overall results of the abduction and internal rotation in respect to turn radii and ground reaction forces indicated that the knee joint movements are likely one of the key points in alpine skiing techniques. However, the skiing equipment used can still significantly influence the movement strategy.

Key words: Abduction, inertial sensor, rotation, ski turn, three-dimensional joint movements     

Trimethoprim-sulfamethoxazole-related hallucinations

Although adverse drug reactions are a well-recognized cause of mental status changes in the elderly, antimicrobials are not often implicated. Trimethoprim-sulfamethoxazole-induced hallucinations in immune-competent patient with switching to nitrofurantoin and risperidone, without associated polypharmacy, have not been reported in the literature. In this case report, we present an 86-year-old Caucasian immune-competent female with major depressive disorder and insomnia who developed hallucinations when treated with two trimethoprim-sulfamethoxazole tablets (80 mg/400 mg) in every 12 hours (4 tablets daily) because of lower urinary infection. After trimethoprim-sulfamethoxazole discontinuation and switching to nitrofurantoin and risperidone, symptoms significantly improved.