Augmentation index predicts mortality in patients with aortic stenosis: an echo-tracking study

The International Journal of Cardiovascular Imaging - Aortic valve stenosis (AS) shares similarities with the atherosclerotic process but little is known about the effect of the mechanical...     

Evidence for a decrease in cardiovascular risk factors following recombinant growth hormone administration in abstinent anabolic-androgenic steroid users.

OBJECTIVES: To determine whether six days recombinant human growth hormone (rhGH) in an abstinent anabolic-androgenic steroid (AAS) group had any cardiovascular and biochemical effects compared with a control group. METHODS: Male subjects (n=48) were randomly divided, using a single blind procedure into two groups: (1) control group (C) n=24, mean+/-SD, age 32+/-11 years; height 1.8+/-0.06m; (2) rhGH using group (0.058IUkg(-1)day(-1)) (GH) n=24, mean+/-SD, age 32+/-9 years; height 1.8+/-0.07m. Physiological responses, anthropometry, arterial pulse wave velocity (APWV), blood pressure (BP), heart rate (HR), peak oxygen uptake (VO(2) peak) and biochemical indices were investigated. RESULTS: Body mass index, fat-free mass index and VO(2) peak significantly increased while body fat significantly decreased within GH (all P<0.017). Insulin like growth factor-I significantly increased within GH (P<0.017) and compared with C (P<0.05). Serum sodium significantly increased (P<0.017) and serum homocysteine, high sensitivity C-reactive protein, thyroid stimulating hormone and tetra-iodothyronine (T(4)), significantly decreased within GH (all P<0.017). T(4) significantly decreased compared with C (P<0.05). Arterial pulse wave velocity, peak and recovery systolic and diastolic BP, significantly decreased compared with C (P<0.05). Resting HR and rate pressure product (RPP) significantly increased compared with C (P<0.05). CONCLUSION: The findings of this study suggest that short term use of rhGH may have beneficial effects on endothelial function and specific inflammatory markers of cardiovascular disease in abstinent AAS users, but may have an adverse effect on the cardiovascular system, as evidenced by the increase in resting RPP.     

Are the results of electrophysiological study different in patients with a pre-excitation syndrome, with and without syncope?

AIMS: Syncope in Wolff-Parkinson-White (WPW) syndrome may reveal an arrhythmic event or is not WPW syndrome related. The aim of the study is to evaluate the results of electrophysiological study in WPW syndrome according to the presence or not of syncope and the possible causes of syncope. METHODS AND RESULTS: Among 518 consecutive patients with diagnosis of WPW syndrome, 71 patients, mean age 34.5 +/- 17, presented syncope. Transoesophageal electrophysiological study in control state and after isoproterenol infusion was performed in the out-patient clinic. Atrioventricular re-entrant tachycardia (AVRT) was more frequently induced than in asymptomatic patients (n = 38, 53.5%, P < 0.01), less frequently than in those with tachycardia; atrial fibrillation (AF) and/or antidromic tachycardia (ATD) was induced in 28 patients (39%) more frequently (P < 0.05) than in asymptomatic patients or those with tachycardia. The incidence of high-risk form [rapid conduction over accessory pathway (AP) and AF or ATD induction] was higher in syncope group (n = 18, 25%, P < 0.001) than in asymptomatic subjects (8%) or those with tachycardias (7.5%). Maximal rate conducted over AP was similar in patients with and without syncope, and higher in patients with spontaneous AF, but without syncope. Results were not age-related. CONCLUSION: Tachycardia inducibility was higher in patients with syncope than in the asymptomatic group. The incidence of malignant WPW syndrome was higher in patients with syncope than in asymptomatic or symptomatic population, but the maximal rate conducted over AP was not higher and another mechanism could be also implicated in the mechanism of syncope.     

Interactions between chromosomes, microfilaments and microtubules revealed by the study of small GTPases in a big cell, the vertebrate oocyte

Meiotic divisions during oogenesis in higher eukaryotes are extremely asymmetric giving rise to one gamete, the oocyte, and two polar bodies. In most species, this asymmetric partitioning relies on the eccentric positioning of meiotic spindles. Recent work performed in mouse and frog oocytes has suggested the involvement of small GTPases, such as Cdc42, Rac and Ran both in the control of spindle organization and positioning. The present review summarizes these findings that shed light on the molecular mechanisms by which small GTPases control asymmetric cell divisions in vertebrate oocytes.