Analysis of a selected node of a truss made of cold-rolled sections based on the finite element method

The study presents a comparative analysis of displacements and reduced stresses that occur in the selected node of a truss made of cold-rolled sections. Computations were based on the finite element method using the Autodesk ROBOT Structural Analysis and ANSYS Academic Research Mechanical software. Analysis of the status of the selected node was performed for permanent and variable loads

Assessment of right ventriclar function by tissue Doppler in relation to plasma NT-proBNP concentration in patients with dilated cardiomyopathy

Background: Impairment of right ventricular function is a common finding in patients with dilated cardiomyopathy (DCM). The aim of the study was to assess the function of the right ventricle by tissue Doppler imaging (TDI) in relation to NT-proBNP concentration in patients with DCM. Methods: 29 patients with DCM were studied. Group I (n = 21) constituted of subjects with a NT-proBNP concentration > 500 pg/ml and group II (n = 8) constituted of patients with NT-proBNP < 500 pg/ml. In all patients the TDI parameters for the free-wall of the right ventricle were analysed: velocity of myocardium (VEL), strain (&#949;) and strain rate (SR). Results: There were no significant differences between the two groups with respect to clinical characteristics, parameters of global and regional left ventricular systolic function or between indicators of global right ventricular function. In group I the maximal values of e in the apical and medial segments of the right ventricular free wall were significantly lower than in group II (-17 &#177; 10 vs. -29 &#177; 7%; p = 0.0168 and -13 &#177; 6 vs. -25 &#177; 5%; p = 0.0023 respectively). Moreover, in group I the maximal SR in the apical and medial segments of the right ventricular free wall were significantly lower than in group II (1.56 &#177; 0.6 &#949;-1 vs. -1.071 &#177; 0.5 &#949;-1; p = 0.0358 and -0.99 &#177; 0.38 &#949;-1 vs. -1.55 &#177; 0.37 &#949;-1; p = 0.0044 respectively). Conclusions: Impairment of right ventricular function is most visible in the apical and medial segments. The maximal values of e and SR for the right ventricle free wall are lower in patients with DCM and NT-proBNP > 500 pg/ml. (Cardiol J 2007; 14: 167-173

Short- and long-term outcomes of continuous-flow left ventricular assist device therapy in 79 patients with end-stage heart failure

Introduction An increasing number of patients with end‑stage heart failure, along with a shortage of heart donors, necessitates the use of mechanical circulatory support. Objecti ves This single‑center retrospective study evaluated short- and long‑term outcomes of continuous‑flow left ventricular assist device (CF‑LVAD) therapy in patients with end‑stage heart failure. Patient s and methods We collected and assessed data of 79 patients (77 men, 2 women; mean age, 50.3 years; mean INTERMACS profile, 3.1) implanted with a CF‑LVAD between 2009 and 2017 (HeartMate 3 in 19 patients [24%]; HeartMate 2 in 9 [11.4%]; and HeartWare in 51 [64.6%]). Result s The mean time on CF‑LVAD support was 604 days (range, 1–1758 days). There were 2 device exchanges due to pump thrombosis and 1 explantation due to heart regeneration; 9 patients (11.4%) underwent heart transplant. Stroke (nondisabling, 48%) occurred in 27.8% of patients (ischemic in 9 patients; hemorrhagic, in 14; both types, in 1) despite the standardized anticoagulation regimen. Major gastrointestinal bleeding and pump thrombosis were reported in 13 patients (16.5%), while 18 patients (22.8%) developed driveline infections (recurrent in 15 patients [19%]). Hemorrhagic stroke and bacteremia had a negative impact on survival. Hemorrhagic stroke was the main cause of death. Survival probability was 0.9 at 1 month and 0.81, 0.71, 0.61, and 0.53 at 1, 2, 3, and 4 years, respectively. Conclusions Although CF‑LVAD support is associated with substantial adverse events, they do not significantly affect mortality (except hemorrhagic stroke and bacteremia). Novel devices seem to overcome these limitations, but larger studies are needed to support these findings

Aktywność enzymów antyoksydacyjnych i stężenie aldehydu dimalonowego jako wykładniki stresu oksydacyjnego u kobiet z subkliniczną nieautoimmunologiczną nadczynnością tarczycy

Introduction: The recent investigations point out the significant role of oxidative stress in the development of thyroid gland disease. The present study was designed to investigate the variation of oxidative stae in women with non-autoimmunological subclinical hyperthyroidism. Material and methods: The study was conducted on 20 females with non-autoimmunological subclinical hyperthyroidism and 15 healthy women. Manganase-containing superoxide dismutase (Mn-SOD) and extracellular superoxide dismutase (EC-SOD) plasma activity, and malondialdehyde (MDA) plasma concentration were measured. Results: EC-SOD plasma activity was significantly higher in women with subclinical hyperthyroidism when compared with the control group (13.3 &#177; 2.1 vs. 10.9 &#177; 1.4 NU/ml; p < 0.05), unlike Mn-SOD (4.2 &#177; 0.5 vs. 4.0 &#177; 1.0 NU/ml). MDA plasma concentration increased significantly in women with subclinical hyperthyroidism (3.5 &#177; 1.2 vs. 2.0 &#177; 0.6 &#956;mol/l; p < 0.05). Conclusions: The increased EC-SOD plasma activity may reflect disturbances of oxidative state in subclinical hyperthyroidism. Parallel increase of MDA plasma concentration may indicate enhancement of lipid peroxidationin in patients with subclinical hyperthyroidism.Wstęp: Badania z ostatnich lat wskazują na udział stresu oksydacyjnego w rozwoju schorzeń gruczołu tarczowego. Celem niniejszej pracy jest ocena zmian stanu oksydacyjnego u kobiet z subkliniczną nieautoimmunologiczną nadczynnością tarczycy. Materiał i metody: Badania przeprowadzono u 20 kobiet z subkliniczną nadczynnością tarczycy oraz u 15 zdrowych kobiet. Wykonywano oznaczenia aktywności dysmutazy ponadtlenkowej - izoformy manganowej (Mn-SOD) i miedziowo-cynkowej (EC-SOD), a także stężenia aldehydu dimalonowego (MDA) w osoczu. Wyniki: U kobiet z subkliniczną nadczynnością tarczycy stwierdzono w osoczu wyższą w porównaniu z grupą kontrolną aktywność ECSOD (13,3 &#177; 2,1 vs. 10,9 &#177; 1,4 NU/ml; p < 0,05), natomiast aktywności Mn-SOD nie różniły się pomiędzy grupami (4,2 &#177; 0,5 vs. 4,0 &#177; 1,0 NU/ml). Badania wykazały również, że u kobiet z nadczynnością tarczycy w porównaniu z grupą kontrolną występuje wyższe stężenie MDA w osoczu niż w grupie kobiet zdrowych (3,5 &#177; 1,2 vs. 2,0 &#177; 0,6 &#956;mol/l; p < 0,05). Wnioski: W grupie chorych z subkliniczną nadczynnością tarczycy występują zaburzenia równowagi oksydacyjnej, przejawiające się wzrostem aktywności EC-SOD w osoczu. Towarzyszy temu podwyższone stężenie MDA, świadczące o nasileniu peroksydacji lipidów w tej grupie chorych

Mechanical circulatory support restores eligibility for heart transplant in patients with significant pulmonary hypertension

Background: An increasing number of patients with end‑stage heart failure implies a wider use of left ventricular assist devices (LVADs). Irreversible pulmonary hypertension (PH) is a predictor of unfavorable prognosis and a contraindication to orthotopic heart transplant (OHT). Aims: The aim of this study was to evaluate the effect of continuous‑flow LVAD (CF‑LVAD) support on pulmonary pressure and pulmonary vascular resistance (PVR) as well as the impact of pre‑LVAD hemodynamic parameters on survival during LVAD support. Methods: Data collected from 106 patients who underwent CF‑LVAD implantation in the years 2009 to 2018 (men, 95.3%; mean [SD] age, 51.8 [12] years; mean [SD] INTERMACS profile, 2.9 [1.6]; mean [SD] LVAD support time, 661 [520] days; follow‑up until May 2019) were retrospectively analyzed. Results: Right heart catheterization was performed before LVAD implantation in 94 patients (88.7%), after implantation—in 31 (29.2%), and before and after implantation—in 28 (26.4%). We observed mean pulmonary artery pressure (mPAP) &gt; 25 mm Hg in 65 patients (61.3%) and PVR &gt; 2.5 Wood units in 33 patients (31.1%) before LVAD implantation. A significant improvement after CF‑LVAD implantation was noted in mPAP, pulmonary capillary wedge pressure, transpulmonary gradient, PVR, cardiac output (P &lt; 0.001 for all parameters), and cardiac index (P = 0.003). All patients with initially irreversible PH became eligible for OHT during LVAD support. Survival during LVAD support did not depend on initial mPAP and PVR. Conclusions: In patients with end‑stage heart failure, CF‑LVAD support leads to a significant reduction of pre‑ and postcapillary PH. Survival on CF‑LVAD support is independent of elevated mPAP and PVR before implantation, which suggests that LVADs decrease the risk associated with PH

Fat and Sugar—A Dangerous Duet. A Comparative Review on Metabolic Remodeling in Rodent Models of Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a common disease in Western society and ranges from steatosis to steatohepatitis to end-stage liver disease such as cirrhosis and hepatocellular carcinoma. The molecular mechanisms that are involved in the progression of steatosis to more severe liver damage in patients are not fully understood. A deeper investigation of NAFLD pathogenesis is possible due to the many different animal models developed recently. In this review, we present a comparative overview of the most common dietary NAFLD rodent models with respect to their metabolic phenotype and morphological manifestation. Moreover, we describe similarities and controversies concerning the effect of NAFLD-inducing diets on mitochondria as well as mitochondria-derived oxidative stress in the progression of NAFLD

Ocena prawej komory za pomocą tkankowej echokardiografii doplerowskiej a stężenie NT-proBNP w surowicy u chorych na kardiomiopatię rozstrzeniową

Wstęp: W przebiegu kardiomiopatii rozstrzeniowej (DCM) często dochodzi do upośledzenia funkcji prawej komory. Celem niniejszej pracy była ocena czynności prawej komory z użyciem tkankowej echokardiografii doplerowskiej (TDI) oraz analiza związku między stężeniem N-końcowego mózgowego peptydu natriuretycznego (NT-proBNP) w surowicy krwi a parametrami mechanicznymi prawej komory u chorych na DCM. Metody: Badaniem objęto 29 osób z DCM. W zależności od stężenia NT-proBNP chorych podzielono na grupę I (n = 21), ze stężeniem NT-proBNP powyżej 500 pg/ml, i grupę II (n = 8) ze stężeniem NT-proBNP poniżej 500 pg/ml. Porównywano parametry uzyskane w trakcie badania za pomocą TDI: prędkości miokardium (VEL), odkształcenie ( e) i tempo odkształcania (SR) dla wolnej ściany prawej komory. Wyniki: Analizowane grupy nie różniły się charakterystyką kliniczną, parametrami globalnej i regionalnej funkcji skurczowej lewej komory, a także globalnymi wskaźnikami czynności prawej komory. W grupie I stwierdzono statystycznie znamiennie niższe warto&#339;ci maksymalnego e w segmencie koniuszkowym (-17 &#177; 10% vs. -29 &#177; 7%; p = 0,0168) i środkowym (-13 &#177; 6% vs. -25 &#177; 5%; p = 0,0023) wolnej ściany prawej komory. Ponadto w grupie I stwierdzono istotnie niższe wartości maksymalnego SR w segmencie koniuszkowym (-1,56 &#177; 0,6 s-1 vs. -1,071 &#177; 0,5 s-1; p = 0,0358) i środkowym (-0,99 &#177; 0,38 s-1 vs. -1,55 &#177; 0,37 s-1; p = 0,0044) wolnej ściany prawej komory. Wnioski: Zaburzenia funkcji prawej komory są najwyraźniej zaznaczone w segmencie środkowym i koniuszkowym. Wartości maksymalnego e i SR dla wolnej ściany prawej komory są niższe u chorych na DCM ze stężeniem NT-proBNP powyżej 500 pg/ml w porównaniu z pacjentami z DCM i NT-proBNP poniżej 500 pg/ml. (Folia Cardiologica Excerpta 2007; 2: 194-200