COVID-19 — Toward a comprehensive understanding of the disease

The evidence on the pathophysiology of the novel coronavirus SARS-CoV-2 infection is rapidly growing. Understanding why some patients suffering from COVID-19 are getting so sick, while others are not, has become an informal imperative for researchers and clinicians around the globe. The answer to this question would allow rationalizing the fear surrounding this pandemic. Understanding of the pathophysiology of COVID-19 relies on an understanding of interplaying mechanisms, including SARS-CoV-2 virulence, human immune response, and complex inflammatory reactions with coagulation playing a major role. An interplay with bacterial co-infections, as well as the vascular system and microcirculation affected throughout the body should also be examined. More importantly, a compre­hensive understanding of pathological mechanisms of COVID-19 will increase the efficacy of therapy and decrease mortality. Herewith, presented is the current state of knowledge on COVID-19: beginning from the virus, its transmission, and mechanisms of entry into the human body, through the pathological effects on the cellular level, up to immunological reaction, systemic and organ presentation. Last but not least, currently available and possible future therapeutic and diagnostic options are briefly commented on

First uses of HAART 300 rings for aortic valve repair in Poland – 4 case studies

Introduction: Aortic valve reconstructions using geometric an- nuloplasty rings HAART 300/200 open new era in aortic valve surgery. The HAART technology resizes, reshapes, stabilizes and simplifies aortic valve repair. The HAART aortic repair rings are designed to be implanted directly into aortic annulus (un- der aortic valve leaflets). Aim: We present first in Poland 4 cases of aortic valve recon- structions using geometric annuloplasty rings HAART 300. Material and methods: Two patients had type IA aortic insuf- ficiency (due to El-Khoury classification) – they were treated by HAART 300 ring insertion and ascending aorta prosthesis implantation. Third patient, Marfan with type IB aortic insuf- ficiency was repaired by HAART 300 ring implantation followed by remodeling (Yacoub) procedure. Fourth patient with type II aortic insufficiency (due to RCC prolapse) was repaired by HAART 300 implantation and cusp plication. Results: All patients shows good results on 6 months postop- erative 3D TTE examinations. Conclusions: Presented technique is reproducible and simplify aortic valve reconstructions

Filter life span in postoperative cardiovascular surgery patients requiring continuous renal replacement therapy, using a post dilution regional citrate anticoagulation continuous hemofiltration circuit

Background: Regional citrate anticoagulation (RCA) is the recommended standard for continuous renal replacement therapy (CRRT). This study assesses its efficacy in patients admitted to critical care following cardiovascular surgery and the influence of standard antithrombotic agents routinely used in this specific group. Methods: Consecutive cardiovascular surgery patients treated with post-dilution hemofiltration with RCA were included in this prospective observational study. The primary outcome of the study was CRRT circuit life-span adjusted for reasons other than clotting. The secondary outcome evaluated the influence of standard antithrombotic agents (acetylsalicylic acid [ASA], low molecular weight heparin [LMWH] or fondaparinux as thromboprophylaxis or treatment dose with or without ASA) on filter life. Results: Fifty-two patients underwent 193 sessions of CVVH, after exclusion of 15 sessions where unfractionated heparin was administered. The median filter life span was 58 hours. Filter life span was significantly longer in patients receiving therapeutic dose of LMWH or fondaparinux (79 h [2–110]), in comparison to patients treated with prophylactic dose of LMWH or fondaparinux (51 h [7–117], p < 0.001), and patients without antithrombotic prophylaxis (42 h [2–91], p < 0.0001). 12 bleeding episodes were observed; 8 occurred in patients receiving treatment dose anticoagulation, 3 in patients receiving prophylactic dose anticoagulation and 1 in a patient with no antithrombotic prophylaxis. Conclusions: A post dilution hemofiltration with RCA provides prolonged filter life span when adjusted for reasons other than clotting. Patients receiving treatment dose anticoagulation had a significantly longer filter life span than those who were on prophylactic doses or ASA alone

Novel algorithm for arrhythmogenic focus localization in patients with right ventricular outflow tract arrhythmias

Background: Previously presented new electrocardiography (ECG) algorithm for localization of arrhythmogenic focus (AFo) in right ventricular outflow tract (RVOT) was based on spontaneous arrhythmia QRS morphology analysis. The aim of this study was to estimate the clinical value of our RVOT algorithm in a prospective study.Methods and results: Algorithm validation was made on 62 patients with RVOT arrhythmias (45 women), mean age 41.6 ± 14.3 years, scheduled for transcatheter ablation. Results of preablation ECG analysis with RVOT algorithm were matched with successful ablation sites and statistical indices: sensitivity (sens), specificity (spec), and positive and negative predictive values (PPV, NPV) were calculated for algorithm and for each of 9 RVOT zones (septal and free wall). An algorithm precisely localized AFo in 57 out of 62 patients (sens 91.3%, spec 99%, PPV 91%, NPV 98.8%). Sensitivity values for superior RVOT aspect (71% patients) varied from 88% to 100%, specificity from 95.9% to 100%; PPV values from 85.7% to 100%, NPV from 92.5% to 100%. Although the total number of patients was relatively small in the 2 remaining RVOT aspects (29% patients) high values (sens, spec, PPV, NPV) were gained for intermediate and inferior zones.Conclusions: On the basis of spontaneous arrhythmia QRS analysis, a novel algorithm was built for preablation localization of RVOT arrhythmia in 1 of the 9 RVOT zones. Prospective analysis of our ECG algorithm confirmed that it is a valuable tool to predict the site of successful ablation in patients with RVOT arrhythmias.

Succinate Dehydrogenase-Deficient Renal Cancer Featuring Fructose-1,6-Biphosphatase Loss, Pyruvate Kinase M2 Overexpression, and SWI/SNF Chromatin Remodeling Complex Aberrations: A Rare Case Report

Succinate dehydrogenase (SDH)-deficient renal cancer is a rare renal cancer subtype recently accepted by the World Health Organization as a unique subtype of renal cell carcinoma (RCC). Here we report a case of 17-year old man. The detailed evaluation indicated occurrence of the SDHB-deficient RCC. The genetic testing revealed no germline mutation in SDH genes. Immunohistochemistry showed SDHB deficiency, overexpression of pyruvate kinase M2 and dramatic downregulation of fructose-1,6-bisphosphatase metabolic enzymes, and unaltered levels of phosphorylated AMP-activated protein kinase and mammalian target of rapamycin. Strong upregulation of INI1 and BRG1 and overexpression of BAF180, subunits of SWI/SNF ATP-dependent chromatin remodeling complex, were also found. The identified tumor pathologically did not resemble clear cell renal cell carcinoma (ccRCC), but some metabolic alterations are common for both cancer types. Thus, we postulate that the phenotypical differences between ccRCC and SDHB-deficient RCC may be related to distinct molecular and metabolic alterations

Two-particle correlations in azimuthal angle and pseudorapidity in inelastic p + p interactions at the CERN Super Proton Synchrotron

Results on two-particle ΔηΔϕ correlations in inelastic p + p interactions at 20, 31, 40, 80, and 158 GeV/c are presented. The measurements were performed using the large acceptance NA61/SHINE hadron spectrometer at the CERN Super Proton Synchrotron. The data show structures which can be attributed mainly to effects of resonance decays, momentum conservation, and quantum statistics. The results are compared with the Epos and UrQMD models.ISSN:1434-6044ISSN:1434-605

Discrete Optimization Algorithms

x, 541 tr. ; 24 cm

An Expert Approach to an Assessment of the Needs of Land Consolidation within the Scope of Improving Water Resource Management

The objective of this study is to present the approach to assess needs of land consolidation to prepare rural areas for proper water resource management. The study presented links of water management with land consolidation, which is a new approach in rural development planning in Central Europe. The results of this research are presented in the form of a needs assessment matrix for water retention. The matrix includes the main groups of parameters that are related to water resource management systems and rural development planning, which are classified into three groups: (1) water resources and retention, (2) technical systems and water management measures, and (3) information about land space distribution in rural areas. A verification of the proposed matrix was carried out for two sites that differ in terms of factors influencing the retention size; one is located in southern Poland in Lower Silesia—in the village of Mokrzeszów—and the other is located in Strzelce Wielkie—a village located in Lesser Poland. Both sites were evaluated using different needs assessment methods in terms of retention. The main factors influencing a reduced retention potential are related to the insufficient retention capacity of river channels and valleys and the inadequate maintenance of melioration systems. In Strzelce Wielkie, the land consolidation favours longer catchment response on rainfall, which is an advantage to mitigating drought and flood problems. The developed matrix can be applied for an assessment of the retention potential of rural areas based on the relatively accessible data. The method is universal and can be used in different regions. The approach presents practical tools dedicated to authorities to deciding on land consolidation in regards to water resources management; it aims at resolving agricultural land use conflicts and sustainably using space in order to manage water domains