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Sirtuins, silent information regulator 2 (Sir 2) proteins, belong to the family of NAD(+)-dependent enzymes with deacetylase or mono-ADP-ribosyltransferase activity. These enzymes are responsible for processes of DNA repair or recombination, chromosomal stability and gene transcription. In mammals, sirtuins occur in seven varieties, from 1 to 7 (SIRT1-SIRT7), differing among themselves with location. SIRT1, the best known variety, exerts its effects on proteins via NAD(+) coenzymes, being thus associated with cellular energetic metabolism and the 'red-ox' state. Its deficits are, among others, concomitant with stressful situations and associated with pathophysiologies of many medical conditions, including diabetes mellitus, cardiovascular diseases, neurodegenerative syndromes and kidney diseases. In kidney disorders, it promotes (stimulates) the survival of cells in an affected kidney by modulating their responses to various stress stimuli, takes part in arterial blood pressure control, protects against cellular apoptosis in renal tubules by catalase induction and triggers autophagy. More and more available in vitro and in vivo data indicate SIRT1 activity to be oriented, among others, towards nephroprotection. Thus, SIRT1 may become a novel element in the therapy of age-related renal diseases, including diabetic nephropathy.

Pediatric patients suffering from valve bladder syndrome (VBS) are at risk of developing chronic kidney disease (CKD) and renal failure in later life. Therefore, it is of vital importance to determine the risk factors and the best possible strategies for diagnosis and treatment in patients with VBS that would minimize the risk of developing CKD. In this review we have presented the current knowledge of CKD risk factors in patients with posterior urethal value (PUV). We have also discussed possible recommendations for prenatal diagnostics procedures to be undertaken in patients with PUV, postnatal monitoring and therapeutic strategies that could reduce the risk of developing CKD in this population. Although in most cases there are no clear guidelines for appropriate clinical actions that can be undertaken in patients with PUV to minimize the risk of kidney failure, we have tried to present concise and accurate advice for physicians taking care of patients with PUV.

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Patients with end-stage renal disease are affected by cardiovascular complications, including disturbances of the heart intraventricular conduction. Body surface potential mapping is a non-invasive electrocardiographic detection method of initial disturbances in heart activation propagation. A goal of the study was to analyze the effects of single hemodialysis (HD) session on ventricular activation time (VAT) maps obtained from hemodialyzed children. The study group consisted of 13 hemodialyzed children (age: 6-18 years). The control group is composed of 26 healthy subjects. In each HD patient, 12-lead electrocardiogram and echocardiography examinations were performed. Isochrone heart maps, reflecting body surface distribution of VAT isolines, were recorded from an 87-electrode HPM-7100 system for body surface potential mapping, before (group B) and after HD session (group A). The distribution of isochrones and VAT values, as recorded in the HD patients, differed significantly from the reference VAT map for controls. The highest VAT maximal value was noted in group B (Me: 110 vs. 62 ms in the control group; P < 0.001), becoming significantly lower after HD session (Me: 98 ms for group A vs. 110 ms for group B; P < 0.001). Ventricular activation time maps, recorded before HD session, showed significant VAT delays with isochrone arrangement specific for the left bundle branch block. After HD session, VAT maps presented significant changes, suggesting a normalization process. Ventricular activation time maps in children with end-stage renal disease exhibited disturbances of intraventricular conduction within the left bundle branch block, undetectable on standard electrocardiogram. A single HD session resulted in VAT map improvement related to overall HD treatment duration.