Preparation of Silver Nanoparticle Composite Material and Its Role in Electrocardiogram Treatment of Acute Myocardial Infarction

2020 ◽  
Vol 12 (10) ◽  
pp. 1572-1580
Author(s):  
Yuanshu Hui ◽  
Liping Liu ◽  
Fugang Chen ◽  
Lihong Huang

The surface resonance scattering of silver nanoparticles, commonly used to enhance the matrix of the Raman, is the most active of all metal nano particles which can greatly improve the sensitivity of the detected molecules. At the same time, the sterilization ability of silver is also highly recommended in the field of biology. In this study, cytosine nucleoside was used as a template to quickly synthesize silver-based composite nanomaterials (Ag–C/Au) with enhanced fluorescence and good water solubility. Then, the fluorescence spectrum, lifetime, the ultraviolet-visible absorption spectrum of the material, and the size and shape of the grain size were studied through characterization. After that, the interaction between the silver-based composite nanomaterial Ag–C/Au and the recombinant protein ephrin-b2 was studied by spectroscopy, and the mixed metalloprotein was used for electrocardiogram treatment of myocardial infarction in SD rats to establish a rat modeling, then the rats were grouped according to the different injections, and the heart rhythm variability (HRV) of different groups of rats with myocardial infarction (MI) was recorded. Finally, the program electrical stimulation (PES) was used to analyze the ventricular effective refractory period (VERP) and ventricular arrhythmia (VAs) in rats. In the experiment, Ag–C/Au nanomaterials produced strong yellow fluorescence under 370 nm ultraviolet excitation, with an approximate particle size of 1.6 nm; through spectral data fitting, it was found that the recombinant protein ephrin-b2 could be adsorbed on the surface of the composite nanomaterials, making the intensity of the characteristic peak decreased; the myocardial indicators of myocardial infarction rats based on ephrin- b2 + Ag–C/Au group were significantly improved, while the grouping of rats using Ag–C/Au alone didn't affect the electrophysiological characteristics after myocardial infarction, that is, ephrin-b2 could improve arrhythmia after myocardial infarction, and the improvement effect would be further strengthened when Ag–C/Au was added.

2013 ◽  
Vol 94 (2) ◽  
pp. 176-180
Author(s):  
I V Logacheva ◽  
N G Barantseva

Aim. To study the change of the main parameters of 24-hour EKG monitoring over time in patients with myocardial infarction associated with ventricular arrhythmias of different grades. Methods. The change of the echocardiography parameters, heart rhythm variability, corrected QT interval duration and dispersion, late ventricular potentials, heart rhythm turbulence were examined in 70 adult men (mean age 52.6±1.3 years) with primary Q-wave myocardial infarction on 10-14th day of the disease and after 6 months. Patients were assigned into 3 groups depending on ventricular arrhythmias severity (according to Lown classification modified by Ryan): А1 (n=29) - grade 1-2, А2 (n=23) - grade 3-4, А3 (n=18) - patients with paroxysmal ventricular tachycardia. Results. Presence of late ventricular potentials and pathologic heart rhythm turbulence in patients in acute period of myocardial infarction suggested high grade of ventricular arrhythmia. Ventricular arrhythmias were associated with severe sympathicotonia, prolongation of corrected QT interval and QT dispersion. 6 months after Q-wave myocardial infarction an autonomic imbalance increased and no positive changes of myocardial homogenicity parameters, late ventricular potentials and pathologic heart rhythm turbulence were observed with increasing ventricular arrhythmia grading and heart rate frequency. A relationship between left ventricle ejection fraction, myocardium mass and myocardial electric non-stability values was revealed. In patients with Q-wave myocardial infarction ventricular arrhythmias are mediated by several mechanisms: systolic and autonomic disorder, repolarization abnormalities, late ventricular potentials pathologic heart rhythm turbulence. The severity of abnormalities is marked by the ventricular arrhythmias grade. Conclusion. 6 months after myocardial infarction (in healing stage) the significant positive changes are found only in patients with 1-2 grades ventricular arrhythmias. The significant non-homogeneity of myocardial electrophysiological features still persists in patients with life-threatening ventricular arrhythmias.


2019 ◽  
Vol 33 (4) ◽  
pp. 90-97
Author(s):  
V. E. Oleynikov ◽  
E. V. Dushina ◽  
M. V. Lukyanova ◽  
Yu. A. Barmenkova ◽  
I. Y. Moiseeva

The aimof the study was to analyze the impact of the status of cardiac autonomic nervous regulation on the fragmentation activity, development and progression of heart failure, and the long-term prognosis in patients with early ST segment elevation myocardial infarction.Material and Methods. The study included 143 subjects; 54 healthy volunteers were examined to identify normal values of heart rhythm variability parameters. The observation group comprised 89 patients with ST segment elevation myocardial infarction who underwent 24-hour ECG monitoring at day 7 to 9 as well as at 24 and 48 weeks with follow up assessment of heart rate variability and late ventricular potentials. At the time points, the levels of brain natriuretic peptide and highly sensitive C-reactive protein were determined. Patients underwent a 6-min walk test every 12 weeks. The development of repeated cardiovascular events has been monitored as an end-point. Patients were assigned to two groups according to results of heart rhythm variability analysis at day 7–9 after onset of ST segment elevation myocardial infarction: group 1 had normal heart rate variability; group 2 had increased sympathetic impact on rhythm.Results. In group 1, a pronounced regression of the brain natriuretic peptide level was registered 24 week after onset of ST segment elevation myocardial infarction. The value of C-reactive protein decreased in all groups. A favorable transformation of the indices reflecting the fragmentation activity — high-frequency low-amplitude and root mean square — of the myocardium was recorded only in the group with normal heart rate variability parameters. The risk of repeated cardiovascular events during 48 weeks after ST segment elevation myocardial infarction was significantly higher in the group with dominant sympathetic activity than in the group with normal status of the autonomic nervous system.Conclusion. Hypersympathicotonia in the acute period of ST segment elevation myocardial infarction was associated with an increased relative risk of repeated cardiac events and negatively affected the dynamics of laboratory parameters indicative of heart failure development and progression.


Kardiologiia ◽  
2020 ◽  
Vol 60 (11) ◽  
pp. 84-93
Author(s):  
V. E. Oleynikov ◽  
E. V. Dushina ◽  
A. V. Golubeva ◽  
Ju. A. Barmenkova

Aim      To identify early predictors for progression of chronic heart failure (CHF) in patients with ST-segment elevation myocardial infarction (STEMI).Material and methods  The study included 113 patients with STEMI aged 52 (95 % confidence interval, 36 to 65) years. 24-h ECG monitoring was performed with assessment of ventricular late potentials, QT dispersion, heart rhythm turbulence (HRT), and heart rhythm variability (HRV); XStrain 2D echocardiograpy with determination of volumetric parameters, myocardial strain characteristics and velocities; and measurement of brain natriuretic peptide (BNP) concentrations. The endpoint was CHF progression during 48 weeks of follow-up, which was observed in 26 (23 %) patients. Based on the outcome, two groups were isolated, with CHF progression (Prg) (26(23%)) and with a relatively stable CHF postinfarction course (Stb) (87 (77 %)).Results At 12 weeks following MI, the Prg group showed increases in left ventricular (LV) end-diastolic dimension (EDD) (р<0.05) and end-diastolic and end-systolic volumes (EDV, ESV), (р<0.01), and EDV and ESV indexes (EDVi and ESVi, р<0.01). In this group, global longitudinal strain (GLS) was decreased at 24 weeks (р<0.05) and global radial strain (GRS) was decreased at 48 weeks (р=0.0003). In the Prg group, values of strain parameters (GLS, global circular strain (GCS), and GRS) were lower at all times. At 7-9 days, 24 weeks, and 48 weeks, the proportion of patients with pathological HRT was higher in the Prg group (38, 27, and 19 % for the Prg group vs 14 % (р=0.006); 3,4 % (р=0.001), and 2.3 % (р=0.002) for the Stb group, respectively). Only in the Stb group, increases in HRV were observed (SDNNi by 13 % (р=0.001), rMSSD by 24 % (р=0.0002), TotP by 49 % (р=0.00002), VLfP by 23 % (р=0.003), LfP by 22 % (р=0.008), and HfP by 77 % (р=0.002). At 7-9 days of MI, the Stb group had greater values of SDANN (р=0.013) and HfP (р=0.01). CHF progression correlated with abnormal values of turbulence onset (TO), disturbed HRT, increased BNP levels and LV ESD, and low values of GLS, GCS, and GRS. Combined assessment of HRT, LV ESD, and GLS at 7–9 days after STEMI allows identifying patients with high risk for CHF progression in the next 48 weeks.Conclusion      The markers for CHF progression after STEMI include abnormal TO values, disturbed HRT, increased BNP levels and LV ESD, and low values of GLS, GCS, and GRS. The multifactor logistic regression analysis revealed early predictors of CHF in the postinfarction period, including abnormal TO, increased LV ESD, and reduced GLS.  


2015 ◽  
Vol 53 (6) ◽  
pp. 646-652
Author(s):  
E. V. Udachkina ◽  
D. S. Novikova ◽  
T. V. Popkova ◽  
E. L. Nasonov

2016 ◽  
Vol 97 (3) ◽  
pp. 453-457
Author(s):  
A N Osmolovsky

Aim. To justify and develop method of endocardial electrode reposition in the right ventricular cavity of the heart in the spontaneous termination of temporary pacing in patients with recurrent myocardial infarction.Methods. A method of endocardial electrode reposition was used in 23 patients with myocardial infarction complicated by acute bradyarrhythmias. Written informed consent was obtained from all patients, and in the absence of contact with the patient, decision to insert temporary artificial pacemaker was made by medical consultation.Results. A method of endocardial electrode reposition that provides threading the electrode from the venous bed to the right ventricular cavity of the heart, cardiac stimulation by electrical impulses and creation the new contacts between electrode and right ventricular endocardium of the heart using the same electrode, both in the presence and in absence of the heart conduction and excitation function, was developed. At the same time, it excludes the electrode dislocation from the right ventricular cavity of the heart, provides the electrode fixation with endocardium, and at the same time allows to impose a stable artificial heart rhythm in the shortest time. During the spontaneous termination of the effective artificial pacemaker, endocardial electrodes reposition enabled to promptly regain the heart rhythm control in all 23 patients with acute bradyarrhythmia of infarction genesis.Conclusion. Effective and safe method of endocardial electrode reposition in the right ventricular cavity of the heart in the spontaneous termination of temporary pacing in patients with recurrent myocardial infarction was developed and introduced into clinical practice.


2019 ◽  
Vol 20 (3) ◽  
pp. 697 ◽  
Author(s):  
Shaoming Jin ◽  
Zhongyao Du ◽  
Huiyuan Guo ◽  
Hao Zhang ◽  
Fazheng Ren ◽  
...  

The glucose analog, 2-deoxyglucose (2-DG), specifically inhibits glycolysis of cancer cells and interferes with the growth of cancer cells. However, the excellent water solubility of 2-DG makes it difficult to be concentrated in tumor cells. In this study, a targeted nano-pharmacosome was developed with folic acid-modified 2-DG (FA-2-DG) by using amino ethanol as a cleavable linker. FA-2-DG was able to self-assemble, forming nano-particles with diameters of 10–30 nm. The biological effects were evaluated with cell viability assays and flow cytometry analysis. Compared with a physical mixture of folic acid and 2-DG, FA-2-DG clearly reduced cell viability and resulted in cell cycle arrest. A computational study involving docking simulation suggested that FA-2-DG can dock into the same receptor as folic acid, thus confirming that the structural modification did not affect the targeting performance. The results indicated that the nano-pharmacosome consisting of FA-2-DG can be used for targeting in a nano-drug delivery system.


2016 ◽  
Vol 94 (4) ◽  
pp. 270-275
Author(s):  
Tat’yana N. Syromyatnikova ◽  
T. V. Obukhova ◽  
B. V. Golovskoy ◽  
M. D. Berg ◽  
Ya. B. Khovaeva ◽  
...  

Connective tissue dysplasia (CTD) occurs in 70% of the patients with obstructive bronchial pathology. It promotes the development of electrical instability of myocardium and life-threatening arrhythmias. We studied electrocardiographic markers of myocardial instability in patients with chronic obstructive bronchial pathology and CTD markers. Such patients were shown to more frequently have ventricular and supraventricular arrhythmias, decreased circadian heart rate index and enhanced heart rhythm variability. Other findings included high frequency of such predictors of sudden cardiovascular death as prolonged and enhanced dispersion of QT intervals, T-wave microalternation, late atrial and ventricular potentials. The arrhythmic activity and the occurrence ofpredictors of sudden cardiovascular death increased in the patients aged above 60 years with obstructive bronchial pathology and CTD.


1993 ◽  
Vol 38 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Jadwiga Gȩbalska ◽  
Krystyna Herbaczyńska-Cedro ◽  
Leszek Ceremużyński

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