Regulation of Papillary Muscle Contractility by NAD and Ammonia Interplay: Contribution of Ion Channels and Exchangers.

Various models, including stem cells derived and isolated cardiomyocytes with overexpressed channels, are utilized to analyze the functional interplay of diverse ion currents involved in cardiac automaticity and excitation-contraction coupling control. Here, we used β-NAD and ammonia, known hyperpolarizing and depolarizing agents, respectively, and applied inhibitory analysis to reveal the interplay of several ion channels implicated in rat papillary muscle contractility control. We demonstrated that: 4 mM β-NAD, having no strong impact on resting membrane potential (RMP) and action potential duration (APD90) of ventricular cardiomyocytes, evoked significant suppression of isometric force (F) of paced papillary muscle.

[ABNORMAL UTERINE BLEEDING IN ADOLESCENT GIRLS: HEREDITARY AND ENVIRONMENTAL RISK FACTORSS].

The objective of this work was to identify prognostic factors of the environment and heredity in the families of girls with abnormal uterine bleeding during puberty. Clinical and genealogical analysis has been carried out according to P. Harper in the families of 70 girls with abnormal uterine bleeding (AUB) during puberty.

Deregulation of Ca-Signaling Systems in White Adipocytes, Manifested as the Loss of Rhythmic Activity, Underlies the Development of Multiple Hormonal Resistance at Obesity and Type 2 Diabetes.

Various types of cells demonstrate ubiquitous rhythmicity registered as simple and complex Ca-oscillations, spikes, waves, and triggering phenomena mediated by G-protein and tyrosine kinase coupled receptors. Phospholipase C/IP-receptors (PLC/IPR) and endothelial NO-synthase/Ryanodine receptors (NOS/RyR)-dependent Ca signaling systems, organized as multivariate positive feedback generators (PLC-G and NOS-G), underlie this rhythmicity. Loss of rhythmicity at obesity may indicate deregulation of these signaling systems.

[PHYSICAL DEVELOPMENT AS A KEY TO THE SUCCESS OF THE FORMATION OF REPRODUCTIVE POTENTIAL].

The aim of this study was to analyze the characteristics of physical and sexual development of patients with menstrual irregularities while monitoring over the past 20 years. Physical and sexual development of 497 patients with abnormal uterine bleeding (AMC PP) and 677 with hypomenstrual syndrome (HMS) aged 10 to 18 years were evaluated who were treated in the period 1997-2002 and 2010-2016. The data were compared with the results of epidemiological studies of a population of schoolgirls in Kharkov region.

Dissecting Cellular Mechanisms of Long-Chain Acylcarnitines-Driven Cardiotoxicity: Disturbance of Calcium Homeostasis, Activation of Ca-Dependent Phospholipases, and Mitochondrial Energetics Collapse.

Long-chain acylcarnitines (LCAC) are implicated in ischemia-reperfusion (I/R)-induced myocardial injury and mitochondrial dysfunction. Yet, molecular mechanisms underlying involvement of LCAC in cardiac injury are not sufficiently studied. It is known that in cardiomyocytes, palmitoylcarnitine (PC) can induce cytosolic Ca accumulation, implicating L-type calcium channels, Na/Ca exchanger, and Ca-release from sarcoplasmic reticulum (SR).