Evaluation of Atrial Electromechanical Delay in Children with Obesity.

Background and Objective: Childhood obesity is one of the worldwide health problems with an increasing prevalence and accompanied by severe morbidity and mortality. It is a serious predisposing risk factor especially for the development of cardiovascular diseases and arrhythmias. Electromechanical delay (EMD) is known to be a predictor for the development of atrial fibrillation (AF). Our study aims to investigate whether EMD, which is a predictor of AF, prolongs in obese children or not. MATERIAL AND METHODS: The study included 59 obese patients aged between 8-18 years and 38 healthy patients as the control group with a similar age and gender. All the individuals underwent transthoracic echo and tissue Doppler echocardiography. Systolic and diastolic left ventricular (LV) functions, inter- and intra-atrial electromechanical delay were measured by tissue Doppler imaging (TDI) and conventional echocardiography. RESULTS: Obese patients had significantly lengthened P-wave on surface ECG to the beginning of the late diastolic wave (PA) lateral, PA septum, intra- and inter-atrial electromechanical delays when compared with the control group (p < 0.001, p = 0.001, p < 0.001 and p < 0.001, respectively) Inter-atrial EMD and intra-atrial EMD correlated positively with body mass index (BMI) values (r = 0.484, p < 0.001 and r = 0.376, p = 0.001; respectively) BMI was significantly related with inter-atrial EMD (ß = 0.473, p < 0.001) However, there was no relationship between inter-atrial EMD and serum glucose and platelet count. CONCLUSION: In our study, we declared that electromechanical delay was increased in obese children when compared to the control group and intra- and inter-atrial electromechanical delay was in correlation with body mass index. Furthermore, we discovered that BMI is an independent predictor of the inter-atrial EMD in obese children.

Quantitation of 24-Hour Moisturization by Electrical Measurements of Skin Hydration.

PURPOSE: The purpose of this study was to quantify the effects of several moisturizers on hydration of the stratum corneum by measuring their effect on electrical conductance over a 24-hour period. DESIGN: Double-blind, randomized controlled trial. SUBJECTS AND SETTING: Twenty-five healthy female volunteers aged 18 to 65 years with dry skin on the lower legs and no other known dermatologic pathology participated in the study. Additional exclusion criteria were pregnant or taking anti-inflammatory steroids. The study was carried out in a clinical research facility in Winnipeg, Manitoba, Canada. METHODS: Subjects underwent a 3-day conditioning period using a natural soap bar on the lower legs and no application of moisturizer to the skin. Participants then came to the test site and equilibrated for at least 30 minutes under controlled conditions of temperature and humidity. After baseline hydration measurements on test sites on the lower legs of each subject, a single application of each of 5 test products at a dose of 2 mg/cm was made. Skin hydration was assessed by electrical conductance measurements with a specialized probe. The probe was briefly placed on the skin surface with light pressure, and the measurement recorded in units of microsiemens (µS). Conductance was measured at 2, 4, 6, 8, and 24 hours after product applications. RESULTS: Although all but 1 of the test products increased conductance at 2 hours, only 2 moisturizers containing high levels of glycerin (products C and E) maintained increased conductance relative to baseline at 24 hours, +37.8 (P < .001) and +103.5 (P < .001), respectively. CONCLUSIONS: Moisturizers containing high levels of glycerin can provide a measurable moisturization benefit as determined by skin conductance for at least 24 hours after a single application.

Heterogeneous composition of voltage-dependent K(+) currents in hepatic stellate cells.

PURPOSE: Hepatic stellate cells (HSC) are a type of pericyte with varying characteristics according to their location. However, the electrophysiological properties of HSC are not completely understood. Therefore, this study investigated the difference in the voltage-dependent K(+) currents in HSC. MATERIALS AND METHODS: The voltage-dependent K(+) currents in rat HSC were evaluated using the whole cell configuration of the patch-clamp technique. RESULTS: Four different types of voltage-dependent K(+) currents in HSC were identified based on the outward and inward K(+) currents. Type D had the dominant delayed rectifier K(+) current, and type A had the dominant transient outward K(+) current. Type I had an inwardly rectifying K(+) current, whereas the non-type I did not. TEA (5 mM) and 4-AP (2 mM) suppressed the outward K(+) currents differentially in type D and A. Changing the holding potential from -80 to -40 mV reduced the amplitude of the transient outward K(+) currents in type A. The inwardly rectifying K(+) currents either declined markedly or were sustained in type I during the hyperpolarizing step pulses from -120 to -150 mV. CONCLUSION: There are four different configurations of voltage-dependent K(+) currents expressed in cultured HSC. These results are expected to provide information that will help determine the properties of the K(+) currents in HSC as well as the different type HSC populations.