The results obtained from experimental investigations into thermal-hydraulic processes that take place during operation of the passive safety systems used in new-generation reactor plants constructed on the basis of VVER technology are presented. The experiments were carried out on the model rigs available at the Leipunskii Institute for Physics and Power Engineering. The processes through which interaction occurs between the opposite flows of saturated steam and cold water moving in the vertical steam line of the additional system for passively flooding the core from the second-stage hydro accumulators are studied. The specific features pertinent to undeveloped boiling of liquid on a single horizontal tube heated by steam and steam-gas mixture that is typical for of the condensing operating mode of a VVER reactor steam generator are investigated.
Background. Secondary hyperparathyroidism (sHPT) is one of the serious complications in chronic kidney disease and is associated with progressive bone disease and vascular calcification.The objective of the study was to determine the impact of Mimpara (Cinacalcet HCl) on mineral disorder, bone turnover and bone mineral density (BMD) versus parathyroidectomy (PTx) in haemodialysis patients’ refractory to alfacalcidol. Materials and methods. 62 haemodialysis patients with sHPT were enrolled in this 6=months prospective study. All of them had surgical indications for PTx. Surgical indications was established according to clinical or biological assessment. 40 patients underwent Mimpara treatment. Dose of Mimpara was titrated every 4 weeks. Sequential doses included 30–180 (mean 59.1 ± 34.2) mg/day. 22 patients underwent PTx. The surgical technique was depended on quantity of hyperplastic parathyroid glands.Results. In 6 months mean iPTH, Ca, Са×Р, CTx and OC levels significantly decreased by 55.7%, 13.8%,34.3%, 21.4 and 1.4% in the Mimpara group vs. 90.7%, 14%, 55.5%, 58.7% and 26.9% in the PTx group. Median serum iPTH level decreased by 30% after initiation of Mimpara in 94.3% patients, from them by 50%in 74.3%. Achieved the KDOQI treatment targets for PTH in 28.6% patients.In 6 months after PTx median serum iPTH level was 100 pg/ml in 50% patients, achieved the KDOQI treatment targets in 27.3%, 300 pg/ml in 18.2%. Median serum 25(ОН)D after PTx significantly increase by 127.3% vs 6.72% in the Mimpara group. In 6 months active restoration of BMD was found in the PTx patients, and patients treated with Cinacalcet showed stabilization of BMD.Mimpara therapy led to a reduction in glandular volume during the course of the study: in both glands with a baseline volume 500 mm3 and with a baseline volume ≥500 mm3. Conclusions. PTx and Cinacalcet therapy improves phosphorus=calcium homeostasis, bone turnover, but bone resorption and formation markers decreased better in the PTx group compared to Cinacalcet group. The effectiveness and safety of Mimpara for secondary hyperparathyroidism were evaluated in dialysis patients’ refractory to alfacalcidol, which reduced the need for parathyroidectomy in patient without severe osteodystrophy.
AIM:To define the prevalence, clinical features, risk factors, and prognostic value of atherosclerotic renal artery stenosis (RAS) in patients with type 2 diabetes mellitus (T2DM).SUBJECTS AND METHODS:One hundred and fifty-seven T2DM patients (63 males and 94 females) aged over 50 years were examined. Screening for RAS was carried out by duplex ultrasound scanning (DUSS); the diagnosis was verified by multispiral computed tomography and magnetic resonance imaging. Moreover, the detection rate of RAS was analyzed from the selective angiographic readings of 30 patients with T2DM and 26 coronary angiography patients without DM who had undergone coronary angiography (CA).RESULTS:In the total group of T2DM patients, the RAS detection rate was 36.9%, as evidenced by DUSS and 43.3% by selective renal artery angiography in the patients who had undergone CA. The factors associated with the development of RAS were smoking (relative risk (RR) = 3.3; p < 0.001); atherosclerosis of coronary (RR = 4.28; p < 0.001) and peripheral (RR = 3.38; p < 0.02) arteries, isolated systolic hypertension (RR = 3.9; p < 0.01), and anemia (RR = 6.4; p < 0.001). In patients with T2DM, RAS was one of the important factors of progressive renal and cardiac diseases and increased mortality determined by the combined end point: death, emergency hospitalization for heart failure, myocardial infarction, double creatinine, and end-stage renal failure (RR = 6.28; p < 0.001).CONCLUSION:The optimization of prognosis in T2DM patients with RAS requires its timely clinical identification in combination with other types of renal lesion, aggressive correction of the mechanisms of the progressive process, and development of medical and endovascular therapies.