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The paper introduces results of computational fluid dynamics (CFD) simulations of water flow at the reactor pressure vessel (RPV) outlet and under the RPV head. Several CFD calculations of the steady-state and dynamic processes involving forced and natural circulation of coolant are presented in the paper. In the steady state regime, several calculations were performed for various number of the reactor coolant system (RCS) loops connected to the reactor and the results have been used to analyse the effect of the RCS configuration to the coolant flow at the reactor outlet and under the reactor vessel head. General flow patterns are described in the outlet part of the reactor and under the reactor vessel head and, also, the influence of a lower flow rate through the reactor on thermal homogeneity of coolant under the vessel head. Simultaneously, we discuss the influence of the coolant flow rate at the core outlet on the heat transfer from the under-head space. Unsteady calculation was also done for a reactor cool-down in the regime of natural circulation. The calculation conditions correspond with the data obtained from the experiments led in the frame of the cool-down process of VVER440 reactor at Mochovce nuclear power plant in 2003. In the calculations, the main attention was applied to establishing the basic trends in the cool-down of water content at the outlet part of the reactor and under the head of the reactor vessel.

The round goby Neogobius melanostomus (Pallas, 1814) is one of the most problematic invasive fish species in recent years in Europe. It has proliferated from its native Ponto-Caspian region to several European river systems including their mouths and coastal brackish waters and was also introduced to and became widely established in the Great Lakes in North America. Despite recent reports about further invasions of round goby in the Odra and Vistula Rivers, including penetration of Baltic and North Seas, in the Elbe River this species was only recorded near its mouth close to Hamburg. Here we report the occurrence of round goby 622 km upstream from the previous record in Geesthacht (Germany) in the upper part of the Elbe River in Usti nad Labem (Czech Republic). This report illustrates the fast spread of round goby through several possible pathways, but the most certain is an introduction in ballast water.

Aim: An overview of MRI in patients with implanted vagal nerve stimulator (VNS) and the method of surgical explantation of VNS, reflect--ing the MRI protocol al-low--ing the subsequent MRI examination without significant limitations. Patients and methods: MRI can also be safely performed in patients with the implanted VNS device. Head examination and body examination caudal-ly from Th8 can be performed, but only local radiofrequency coils must be used. Before the MRI, the VNS system must be reprogram-med. If the patient has an explanted generator and the larger part of the electrode, the MRI of the entire body can be performed with any com-mon MRI setting. This applies to a situation where after the explantation there is only a 2- cm part of the electrode left –  cor-respond--ing to the portion of the electrode on the vagal nerve with fixation anchors. Results: From June 2016 to June 2018, we explanted a VNS with this approach in six patients. Post-operative course of all patients was without complications. Post-operative control was performed using neck X-ray and CT 3D imaging. Imag--ing methods showed that the remainder of the electrode on the vagal nerve electrode was ≤ 2 cm. Post-operatively, patients did not have swallowing dif-ficulties, hoarseness or voice changes. Four patients have subsequently already undergone MRI without any dif-ficulties or complications. Conclusion: Surgical explantation of VNS accord--ing to the MRI protocol, leav--ing part of the electrode on the vagal nerve and omitt--ing the complete preparation of the entire electrode on the nerve, reduces the risk of complications and shortens the duration of the operation. The patient can afterwards safely undergo the MRI of the entire body without any limitations in normal technical settings. Autoři deklarují, že v souvislosti s předmětem studie nemají žádné komerční zájmy. Redakční rada potvrzuje, že rukopis práce splnil ICMJE kritéria pro publikace zasílané do biomedicínských časopisů. [ABSTRACT FROM AUTHOR]

In 1984, we started using therapeutic plasmapheresis (plasma exchange) as a method of extracorporeal lipoprotein elimination for the treatment of hypercholesterolemic patients. We evaluated the results of long-term therapy in 14 patients, 8 men and 6 women. The average age was 55.6±13.2 (range 28-70), median 59.5 years. 14 patients were diagnosed with familial hypercholesterolemia (FH): 5 homozygous, 9 heterozygous. Ten patients in the group were treated using immunoadsorption lipoprotein apheresis and 4 using hemorheopheresis. Immunoapheretic interventions decreased LDL-cholesterol (82±1 %), ApoB (73±13 %) and even Lp(a) by 82±19 %, respectively. Selected non-invasive methods are important for long-term and repeated follow-up. Carotid intima-media thickness showed improvement or stagnation in 75 % of the patients. Biomarkers of endothelial dysfunction such as endoglin (in the control group: 3.85±1.25 μg/l, in lipoprotein apheresis-treated hypercholesterolemic individuals 5.74±1.47 μg/l), CD40 ligand (before lipoprotein apheresis: 6498±2529 ng/l, after lipoprotein apheresis: 4057±2560 ng/l) and neopterin (before lipoprotein apheresis: 5.7±1.1 nmol/l, after lipoprotein apheresis: 5.5±1.3 nmol/l) related to the course of atherosclerosis, but did not reflect the actual activity of the disease nor facilitate the prediction or planning of therapy. Hemorheopheresis may improve blood flow in microcirculation in familial hypercholesterolemia and also in some other microcirculation disorders via significantly decreased activity of thrombomodulin (p<0.0001), tissue factor (p<0.0001), aggregation of thrombocytes (p<0.0001) and plasma and whole blood viscosity (p<0.0001). In conclusion, lipoprotein apheresis and hemorheopheresis substantially lowered LDL-cholesterol in severe hypercholesterolemia. Our experience with long-term therapy also shows good tolerance and a small number of complications (6.26 % non-serious clinical complications). [ABSTRACT FROM AUTHOR]

This 4-month study (10 May - 6 September 2012) evaluated the effects of supplementary feeding on common carp ( Cyprinus carpio Linnaeus, 1758) growth, water quality, natural food availability and nutrient balance under different pond treatment regimes (eight rectangular earthen ponds; 0.03 ha surface area; 3-year-old carp). The nitrogen and phosphorus budgets were calculated as the difference between input (food, fish stocked and influent water) and output (effluent water and fish harvested). Three types of supplementary feeds were used: wheat, thermally-treated wheat, and thermally-treated and pressed wheat. An additional test group was provided with naturally available forage only and served as a control. The type of supplementary feed did not influence the water quality, with the exception of dissolved oxygen. No significant differences among experimental ponds were observed in zooplankton abundance. The use of modified cereals (especially thermally-treated and pressed wheat) improved carp growth performance and resulted in lower nutrient concentrations in effluent water via improving their digestibility. Both thermally-treated and thermally-treated and pressed cereals improved the balance of phosphorus; hence these diets could be beneficial, not only from the fish production point of view but also as a tool to reduce the deterioration of pond water quality. [ABSTRACT FROM AUTHOR]

Introduction. Familial hypercholesterolemia is a hereditary disorder with autosomal dominant heredity. The underlying cause involves the gene for the LDL-receptor leading to accelerated atherosclerosis. Extracorporeal elimination of cholesterol (CH) is indicated in 3-5% of patients not responding to conservative treatment or in homozygous FH. Two methods are used at our institution: immunoadsorption of LDL- cholesterol and rheohemapheresis. Patients and Methods. We currently have long term follow-up available for 14 patients with familial hypercholesterolemia (8 males, 6 females) aged 28-70 years (median 57 years). 10 patients are treated with immunoadsorption (5 homozygous and 5 heterozygous) and 4 patients are treated with rheohemapheresis (2 males, 2 females). Median follow-up is 8.5 years. During immunoadsorption, plasma is collected by continuous separation and flows through alternating pairs of adsorbers in an automatic adsorbing-desorbing device. In rheohemapheresis, plasma is collected similarly but goes through a "second step" - filter. Procedures are repeated every 2-4 weeks. Cholesterol and LDL- cholesterol values are measured before and after each procedure. Results. 1922 procedures have been performed (immunoadsorption 1590 times, rheohemapheresis 332 times). Average cholesterol and LDL- cholesterol values before the procedure were 5.34 and 3.12 mmol/l in immunoadsorption, 5.07 and 2.86 in rheohemapharesis; after the procedure: 1.73 and 0.72 (a fall of 72% and 85%), resp. 1.96 and 0.97 mmol/l (a drop of 61% and 66% drop). Fibrinogen fell by 22% (from 3.05 to 2.42 g/l) and 64% (from 3.48 to 1.2g/l). There were 3.1% of adverse reactions and no difference was observed between the two methods. Conclusion. Treatment of FH is very effective when indicated. There is a significant decrease in all observed parameters. No patient experienced worsening of atherosclerosis. Both methods are safe with minimum adverse reactions. Immunoadsorption is more effective in CH elimination. RHF can be used in patients with hyperfibrinogenemia as an additional risk factor of atherosclerosis. Care of these patients is costly and requires an experienced team and an interdisciplinary approach. [ABSTRACT FROM AUTHOR]

Higher biomass especially of some aquatic macrophyte species offered a higher density of phytophilous zoobenthos, but did not increase the proportion of non‐planktonic to planktonic prey in young‐of‐the‐year perch Perca fluviatilis. Both abundance and biomass of non‐planktonic prey dominated over planktonic prey in the pond with lower biomass of aquatic macrophytes and lower food. Survival of P. fluviatilis was lower (20%) in the pond with lower food than in the other pond (34%), however, specific growth rate (1·3% day−1) and final Fulton's condition factor of P. fluviatilis were similar in both ponds. [ABSTRACT FROM AUTHOR]

Sudden hearing loss (sudden idiopathic sensorineural hearing loss, SISHL) is a major medical, social and economic problem. The etiology is not fully understood; the problem is arising presumably by the action of heterogeneous factors (viral infections, immunologic or vascular disorders etc.). Treatment of SISHL is generally not satisfactory, both in terms of corticosteroids or other options. Rheohemapheresis (RHF) offers a possibility of a rescue treatment. It is based on a rapid improvement of rheologic properties of blood that can favorably affect the viscosity and thus the flow of the microcirculation, coagulation or activity of the endothelium. In the years 2012-2013, we treated 16 patients in the age 34-72 years by means of our own modification of RHF, after treatment failure with corticoid infusion therapy. Hearing improvement was achieved significantly in 11 patients according to WHO rating, respectively in 12 diseased according to Fowler counting. 5 patients did not improve significantly, at one patient the hearing worsened. Most patients achieved an improvement at a frequency of 0.5 kHz. Tinnitus disappeared in two patients, and average tinnitus reduction was achieved 15.25 dB. Unfavorable prognostic factor showed to be the severity of hearing loss and age of the patient and the time of the incident. RHF side effects were not significant (two short-term non-serious reactions). RHF in our study showed a beneficial therapeutic effect even after a failed conventional therapy and subsequent initiation of treatment and was not associated with significant adverse risks. Treatment results of our group support the hypothesis that RHF may be an alternative rescue therapy in SISHL, especially in case of a vascular etiology, even after a failure of a standard therapy. [ABSTRACT FROM AUTHOR]

Background. Using our statin analysis method, it was possible to uncover a significant drop in statin levels (atorvastatin, simvastatin, and metabolites) after extracorporeal LDL-cholesterol elimination (EE) in severe familial hypercholesterolemia (FH). The purpose of this work was to identify the mechanism underlying this drop and its clinical significance as well as to proposemeasures to optimize a pharmacotherapeutical regimen that can prevent the loss of statins. Methods. Ultra High Performance Liquid Chromatography (UHPLC) connected to the triple quadrupole MS/MS system was used. Patients. A group of long-term treated patients (3-12 years of treatment) with severe FH (12 patients) and treated regularly by LDL-apheresis (immunoadsorption) or haemorheopheresis (cascade filtration) were included in this study. Results. After EE, the level of statins and their metabolites decreased (atorvastatin before/after LDL-apheresis: 8.83/3.46 nmol/l; before/after haemorheopheresis: 37.02/18.94 nmol/l). A specific loss was found (concentration of atorvastatin for LDL-apheresis/haemorheopheresis: 0.28/3.04 nmol/l in washing fluids; 11.07 nmol/l in filters). To prevent substantial loss of statin concentrations, a pharmacotherapeutic regimen with a longer time interval between the dose of statins and EE is recommended (15 hours). Conclusions. A specific loss of statins was found in adsorbent columns and filters. The decrease can be prevented by the suggested dosage scheme. [ABSTRACT FROM AUTHOR]

Rheological conditions basically influence tissue perfusion, oxygen and nutrient supply, tissue regeneration and in its consequence the course of pathological processes, especially in microcirculation and partially even in macrocirculation. Haemorheotherapy has shown to be successful in several indications (critical disorders in microcirculation) when other methods of therapy have failed. In this study we describe the changes of effectivity indicators in haemorheopheresis treatment and their clinical importance in cases of eye microcirculation, statoacoustic apparatus and disorders of the lower extremities. We treated with haemorheopheresis (separator Cobe.Spetra + Evaflux filter) 24 patients (16 patients with age related macular degeneration, 5 with critical peripheral arterial foot disease, and 3 with acute hearing loss). After the procedures α2-macroglobulin decreases by about 58%, fibrinogen by about 69%, IgM by about 61%, LDL-cholesterol by about 77%, apolipoprotein B by about 76% and lipoprotein(a) by about 63%. It corresponds with a decrease in blood and plasma viscosity and clinical improvement in the observed patients, i.e. visual improvement, acceleration of tissue defect healing and improvement in hearing. We noticed 7.1% clinically insignificant side-effects. The method of haemorheopheresis was safe. It led to improvement in patients' clinical condition in the above mentioned indications when other methods of treatment failed. [ABSTRACT FROM AUTHOR]

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AC133 antibody provides an alternative to CD34 for the selection and characterization of cells necessary for engraftment in transplant situations. We studied the effect of stem cell factor (SCF), interleukin 3 (IL-3) and interleukin 11 (IL-11) on the ex vivo expansion of human CD34+/AC133+ progenitors isolated from leukapheresis products from chemotherapy plus granulocyte-colony-stimulating factor (G-CSF) -mobilized adult donors. MiniMACS AC133+ isolated cells contained a mean of 85% (80-90) AC133+ cells. Enriched AC133+ cells co-expressed CD34+ 80%, CD71low 36.6 % and CD33+ 6.6 %. After a seven-day ex vivo expansion in the presence of SCF + IL-3 + IL-11, the number of cells increased 19 times. These cells expressed a mean 12% CD34+ and 74% CD71+ (23% CD 71high) and 59% CD33+. This means that the absolute number of CD34+ cells increased slightly, the number of CD33+ increased 100 times and cells with high density CD71high (23%) appeared. These cells represent the cells committed to erythroid differentiation. The increase in the number of CFU-GM with various combinations of cytokines SCF + Il-3 + IL-11 will be discussed. The number of CFU-GM in culture after a seven-day ex vivo expansion in the presence of SCF + IL-3 + IL-11 increased 45 times. [ABSTRACT FROM AUTHOR]

The therapeutic method of reverse isolation in patients using an aseptic environment in the Life Island or Laminar Air Flow Unit apparatus systems is described on the basis of data from the literature and the authors' experience. A historical summary of views on treatment in an aseptic environment is followed by a description of the method of work with the system of reverse isolation, including important technical, operational and other data. The main indications for treatment are given and the authors' experience with the reverse isolation of 36 patients suffering from blood diseases who were treated in this way over the past four years is evaluated. The experience gained confirms data from the literature that reverse isolation is unequivocally successful in reducing the number of infections in immunologically weakened persons. Other aspects have not yet been definitely assessed. [ABSTRACT FROM AUTHOR]

Examines the advantages of large volume erythrocytapheresis (LVE) therapy in patients with erythrocytosis. Improvement in symptomatology; Causes of polyglobulia; Efficacy of LVE therapy.