Evaluation of Fibrosis Markers as a Potential Method for Diagnosing Non-Obstructive Coronary Artery Disease in Patients with Stable Coronary Artery Disease

Aim. To study the levels of fibrosis markers in patients with stable coronary artery disease (CAD) and various types of coronary artery (CA) lesions (obstructive and non-obstructive), to identify possible differences for diagnosing the types of coronary obstruction.Material and methods. The observational study included three groups of patients: with non-obstructive (main group, coronary artery stenosis <50%; n=20) and obstructive (comparison group, hemodynamically significant coronary artery stenosis according to the results of coronary angiography; n=20) CAD and healthy volunteers (control group; n=40). Transforming growth factor beta 1 (TGF-β1) and matrix metalloproteinase 9 (MMP-9) levels were measured in plasma by enzyme immunoassay. According to the results of echocardiography, all patients included in the study were divided into four groups depending on the type of myocardial remodeling.Results. TGF-β1 levels were significantly higher in patients with obstructive CAD (p=0.008) than in patients with non-obstructive CAD and healthy volunteers (p <0.001). There were no significant differences between the main and control groups (p>0.05). There were no statistically significant differences in TGF-β1 levels depending on the type of left ventricular remodeling (p=0.139). The maximum level of MMP-9 was in the group with obstructive coronary disease and significantly differed from the main group (p <0.001) and the control group (p=0.04).Conclusio. The maximum levels of TGF-β1 and MMP-9 were found in the group with obstructive coronary artery disease. The levels of these biomarkers in the main group were statistically different from the values obtained in the control group. Thus, considering the pathogenesis of the development of non-obstructive CAD, the use of fibrosis markers TGF-β1 and MMP-9 may be promising for diagnosing the severity of CA obstruction

Plasma Level’s of Neuregulin-1 in Healthy People

Aim. To determine the median levels of neuregulin-1 (NRG-1; endothelium-derived growth factor and the natural agonist of the ERBB3 and ERBB4 receptors) NRG-1 in healthy volunteers and to study the associations of NRG-1 levels with gender and age.Material and Methods. Ninety seven healthy participants were enrolled (median age of 44 [32-54], men 45 men [46.4%]). The following age groups were identified: 20-29 y.о. (n=20, men – 50.0%),  30-39  y.о.  (n=21,  men  –  52.4%),  40-49  y.о.  (n=22,  men  –  45.5%),  50-59  y.о. (n=22, men – 36.4%); 60-69 y.о. (n=12, men – 50.0%). Peripheral blood samples were collected at the time of enrolment, standard laboratory tests were performed, and NRG-1 levels were determined in the plasma samples by ELISA.Results. In the cohort of 97 healthy participants the median value of NRG-1 was 0.3 [0.121-2.24] ng/ml. NRG-1 levels did not differ significantly between men and women (p=0.145), indicating that NRG-1 levels are not influenced by gender. The levels of NRG-1 were similar in the different age groups: age 20-29 years=0.26 [0.17-0.37] ng/ml; age 30-39=0.24 [0.1-0.39] ng/ml; age 40-49=0.31 [0.19-1.15] ng/ml; age 50-59=0.37  [0.19-1.0] ng/ml; age 60-69=0.4 [0.13-0.81] ng/ml. Correlation analysis between NRG-1 levels and route blood measurements (haemoglobin, lipids, glucose, creatinine, and uretic acid) did not show significant associations.Conclusions. In this study, the median value of NRG-1 plasma levels were determined. The results of the study show that age and gender had no influence on NRG-1 values

Neuregulin-1β, Biomarkers of Inflammation and Myocardial Fibrosis in Heart Failure Patients

Neuregulin-1β (NRG-1) is an emerging biomarker of heart failure (HF). The mechanisms of its action in HF patients are yet  to be investigated. Cardioprotective and anti-inflammatory  effects of NRG-1 have been reported.Aim. To assess NRG-1 levels in HF patients and investigate the association between NRG-1 and biomarkers of inflammation and myocardial fibrosis.Material and Methods. NRG-1, biomarkers of inflammation and fibrosis (hsCRP, IL-6, sVCAM-1, MMP-9, Galectin-3, ST2, TGF-β) were assessed in 47 patients with HF and preserved ejection fraction (HFpEF); 39 patients with HF and reduced ejection  (HFrEF) and 40 healthy participants. The associations between  NRG-1 and biomarkers of inflammation and fibrosis, as well as  the composite outcomes of cardiovascular death and HF  hospitalisations were assessed.Results. Median NRG-1 levels in HFpEF were 0.969 (0.348; 1.932) ng/ml, in HFrEF – 0.63 (0.348; 1.932), in healthy participants 0.379 (0.195; 0.861) ng/ml, and was significantly higher in HFpEF compared to healthy volunteers (р=0.004). There was no  difference in NRG-1 concentration between HFpEF and HFrEF. In  HF patients, all biomarkers of inflammation and fibrosis were  higher than in controls. ST2, IL-6 and TGF-β were significantly higher in HFrEF compared to HFpEF patients, while hsCRP,  sVCAM-1, MMP-9, and Galectin-3 levels were comparable. In  HFpEF, NRG-1 was associated with hsCRP (rs=0.378, p=0.023) and IL-6 (rs=0.378, p=0.014). Median follow-up time in patients with HFpEF and in patients was 312 (236; 388) days, in HFrEF – 147 (98; 237) days. In HFpEF, 2 patients died and 19 were  hospitalized due to HF. In HFrEF, 10 deaths and 19  hospitalizations were registered. Kaplan-Mayer analysis showed that HFpEF patients with increased NRG-1 and IL-6 had higher  levels of HF hospitalisation (log rank test, р=0.046 and р=0.012, respectively). In a multivariable cox proportional hazard model,  the association between the NRG-1 and outcomes remained significant after adjustment for age, gender and NTproBNP but diminished when hsCRP and IL-6 were included in the model.Conclusion. NGR-1 level significantly higher in HFpEF compared to healthy participants, and comparable with NRG-1 concentrations in HFrEF. In HFpEF, NRG-1 was associated with biomarkers of inflammation and fibrosis. The prognostic value of NRG-1 in HF requires further investigations

Left Atrium Involvement in Lymphoma Patients: Single Center Observational Study

Aim. To assess the structure and performance of left atrium (LA) before and after 3 cycles of anticancer treatment in lymphoma patients, as well as the incidences of supraventricular arrhythmia (SVA) and the levels of biomarkers of inflammation.Material and Methods. This is a prospective observational study of patients with confirmed diagnosis of lymphoma [n=23; 57% men; median age 52 (34;64) years], who had no prior polychemotherapy. The comparison group included persons without lymphoma [n=18; 50% men; median age 43 (37; 54) years] comparable with the main group in terms of sex, age and risk factors for cardiovascular diseases. Patients with lymphoma underwent 24h-ECG monitoring and advanced transthoracic echocardiography at baseline and after 3 cycles (within 3 months) of anticancer treatment. Biomarkers of inflammation were measured. The results were compared with the data of the comparison group.Results. In lymphoma patients, LA reservoir, conduit, and booster function were found to be impaired at baseline but were comparable with these in matched controls. After 3 cycles of anticancer treatment, a trend to reduction of LA booster and conduit strain was found. The proportion of those with SVA was significantly higher in lymphoma patients before chemotherapy compared to those after anti-cancer treatment or controls: 57% vs 10% and 33% respectively (p<0.05). Lymphoma patients had a higher number of premature ventricular beats at baseline than after treatment or in control [183 (14;841) vs 38 (14;94) and 9 (4;38) respectively]. There were no associations found between the parameters of LA structure and function and SVA. Moderate positive correlation between ESR and supraventricular premature complexes was found (rS=0.44; p<0.05). A positive correlation between LA contractile function and inflammatory biomarkers were revealed: LA active ejection fraction (LA EFact) and ESR (rS=0.42, p<0.05); LA volume index and β-globulin (rS=0.43, p<0.05); LA EFact and neuregulin-1β (rS=0.42, p<0.05); LA expansion index and neuregulin-1β (rS=0.55, p<0.05).Conclusions. In lymphoma patients, LA phasic strain parameters were impaired regardless of anticancer treatment. The associations between inflammatory biomarkers with SVA and parameters of LA performance were found

Enhancement factor, electrostatic force and emission current in a nanoneedle emitter

We consider field emission from carbon nanotubes and other elongated nanostructures. An exact solution for the electrostatic field between a metallic hemi-ellipsoidal needle on a plate (as a cathode) and a flat anode are presented. The basic idea is to replace the cathode by a linearly charged thread in a uniform electric field and to use a set of “image” charges to reproduce the anode. Exact analytical formulas of the electrical field, field enhancement factor, and electrostatic force are found. Using the Fowler-Nordheim theory we obtain an exact analytical formula for the total current. The field enhancement factor, total force and emission current, as well as their distributions on the top of the needle for a wide range of parameters, have been calculated and analyzed

A method of eliminating false acoustic emission signals in testing experimental structures

15.00; Translated from Russian (Tekhnicheskaya Diagnostika i Nerazrushayushchii Kontrol' 1989 v. 1(3) p. 84-87)Available from British Library Document Supply Centre- DSC:9023.19(VR-Trans--4370)T / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo