41 research outputs found
Characteristic of the active substance of the Saccharomyces cerevisiae preparation having radioprotective properties
The paper describes some biological features of the radioprotective effect of double-stranded RNA preparation. It was found that yeast RNA preparation has a prolonged radioprotective effect after irradiation by a lethal dose of 9.4 Gy. 100 % of animals survive on the 70th day of observation when irradiated 1 hour or 4 days after 7 mg RNA preparation injection, 60 % animals survive when irradiated on day 8 or 12. Time parameters of repair of double-stranded breaks induced by gamma rays were estimated. It was found that the injection of the RNA preparation at the time of maximum number of double-stranded breaks, 1 hour after irradiation, reduces the efficacy of radioprotective action compared with the injection 1 hour before irradiation and 4 hours after irradiation. A comparison of the radioprotective effect of the standard radioprotector B-190 and the RNA preparation was made in one experiment. It has been established that the total RNA preparation is more efficacious than B-190. Survival on the 40th day after irradiation was 78 % for the group of mice treated with the RNA preparation and 67 % for those treated with B-190. In the course of analytical studies of the total yeast RNA preparation, it was found that the preparation is a mixture of single-stranded and double-stranded RNA. It was shown that only double-stranded RNA has radioprotective properties. Injection of 160 μg double-stranded RNA protects 100 % of the experimental animals from an absolutely lethal dose of gamma radiation, 9.4 Gy. It was established that the radioprotective effect of double-stranded RNA does not depend on sequence, but depends on its double-stranded form and the presence of “open” ends of the molecule. It is supposed that the radioprotective effect of double-stranded RNA is associated with the participation of RNA molecules in the correct repair of radiation-damaged chromatin in blood stem cells. The hematopoietic pluripotent cells that have survived migrate to the periphery, reach the spleen and actively proliferate. The newly formed cell population restores the hematopoietic and immune systems, which determines the survival of lethally irradiated animals
Eradication of Krebs-2 primary ascites via a single-injection regimen of cyclophosphamide and double-stranded DNA
Previously, we reported on the development of a therapeutic regimen allowing eradication of primary murine Krebs-2 ascites transplants. This protocol involved multiple injections of dsDNA preparations administered during the NER and HR phases of repair of interstrand DNA cross-links induced by prior cyclophosphamide treatments. Mice treated under this protocol frequently developed secondary ascites, which indicated that some tumor-inducing cancer stem cells could survive the treatment and caused relapse. Further, we observed that animals receiving multiple dsDNA injections developed pronounced systemic inflammatory response. This prompted us to develop a more straightforward treatment regimen based on the synergistic activity of cyclophosphamide and dsDNA preparations, which would allow complete eradication of established primary Krebs-2 ascites and also be less toxic for the treated animals. This protocol relies on a precisely timed single injection of dsDNA during the NER/HR transition period of each repair cycle. Under this protocol, 8-day remission of Krebs-2 engrafted mice was achieved, which was similar to the results of the multiple-injection treatment schedule. We observed an increase in the average life span of Krebs-2- transplanted mice on a single-injection regimen, which was consistent with reduced toxicity of such treatment
Development of the therapeutic regimen based on the synergistic activity of cyclophosphamide and double-stranded DNA preparation which results in complete cure of mice engrafted with Krebs-2 ascites
Cumulative evidence obtained in this series of studies has guided the logic behind the development of a novel composite dsDNA-based preparation whose therapeutic application according to the specific regimen completely cures the mice engrafted with otherwise lethal Krebs-2 ascites. The likely mechanism involves elimination of TAMRA+ tumor-inducing stem cells (TISCs) from Krebs-2 tumors. We performed quantitative analysis of TISC dynamics in Krebs-2  ascites following treatment with the cytostatic drug cyclophosphamide (CP) and untreated control cells. In intact ascites, TISC percentage oscillates around a certain value. Following CP treatment and massive apoptosis of committed cancer cell subpopulation, we observed relative increase in TISC percentage, which is consistent with reduced susceptibility of TISCs to CP. Nonetheless, this treatment apparently synchronizes TISCs in a cell cycle phase when they become sensitive to further drug treatments. We describe the regimen of synergistic DNA + CP activity against Krebs-2 ascites. This protocol results in a complete cure of 50 % of Krebs-2 engrafted mice and involves three metronomic injections of CP exactly at the timepoints when repair cycles are about to finish combined with dsDNA injections 18 hours following each CP injection. The “final shot” uses CP + DNA treatment, which targets the surviving yet highly synchronized and therefore treatmentsensitive cells. The first three CP/DNA injections appear to arrest Krebs-2 cells in late S-G2-M phase and result in their simultaneous progression into G1-S phase. The timing of the “final shot” is crucial for the successful treatment, which eradicates tumorigenic cell subpopulation from Krebs-2 ascites. Additionally, we quantified the changes in several biochemical, cellular and morphopathological parameters in mice throughout different treatment stages
Analysis of different therapeutic schemes combining cyclophosphamide and doublestranded DNA preparation for eradication of Krebs-2 primary ascites in mice
In the present paper, we report on the series of experiments where multiple regimens of CP and dsDNA injections were tested for targeting the ascites form of murine Krebs-2 cancer in situ. We show that combining CP with cross-linked human and salmon dsDNA results in a synergistic toxicity for ascites-bearing mice, an observation supported by the histopathology analysis of organs and tissues of experimental animals. In contrast, using a composite mixture of native and cross-linked human and salmon DNA after CP injections leads to a significant increase in average lifespan of the treated mice. Further, we demonstrate that repeated rounds of CP+dsDNA injections result in dramatic anticancer effect. The timing of injections is chosen so that they target the cells that were insensitive to the previous treatments as they were in the G2/M phase. 3-4 rounds of injections are needed to eliminate the subpopulation of tumor-initiating cancer stem cells. Our experiments identified the regimen when complete resorption of the primary Krebs-2 ascites occurs in all of the treated animals, followed by a remarkable remission period lasting 7-9 days. Yet, this regimen does not prevent secondary site metastases (either solid or ascites form) from developing, which is likely caused by the migration of ascites cells into adjacent tissues or by incomplete eradication of cancer stem cells. To address these and other questions, we expanded the study and performed histopathology analysis, which indicated that secondary metastases is not the only cause of death. In fact, many animals displayed unfolding systemic inflammatory reaction which was culminated by multiple organ failure. Thus, we developed the concept for treating ascites form of Krebs-2 cancer, which allows elimination of the primary ascites
International longitudinal registry of patients with atrial fibrillation and treated with rivaroxaban: RIVaroxaban Evaluation in Real life setting (RIVER)
Background
Real-world data on non-vitamin K oral anticoagulants (NOACs) are essential in determining whether evidence from randomised controlled clinical trials translate into meaningful clinical benefits for patients in everyday practice. RIVER (RIVaroxaban Evaluation in Real life setting) is an ongoing international, prospective registry of patients with newly diagnosed non-valvular atrial fibrillation (NVAF) and at least one investigator-determined risk factor for stroke who received rivaroxaban as an initial treatment for the prevention of thromboembolic stroke. The aim of this paper is to describe the design of the RIVER registry and baseline characteristics of patients with newly diagnosed NVAF who received rivaroxaban as an initial treatment.
Methods and results
Between January 2014 and June 2017, RIVER investigators recruited 5072 patients at 309 centres in 17 countries. The aim was to enroll consecutive patients at sites where rivaroxaban was already routinely prescribed for stroke prevention. Each patient is being followed up prospectively for a minimum of 2-years. The registry will capture data on the rate and nature of all thromboembolic events (stroke / systemic embolism), bleeding complications, all-cause mortality and other major cardiovascular events as they occur. Data quality is assured through a combination of remote electronic monitoring and onsite monitoring (including source data verification in 10% of cases). Patients were mostly enrolled by cardiologists (n = 3776, 74.6%), by internal medicine specialists 14.2% (n = 718) and by primary care/general practice physicians 8.2% (n = 417). The mean (SD) age of the population was 69.5 (11.0) years, 44.3% were women. Mean (SD) CHADS2 score was 1.9 (1.2) and CHA2DS2-VASc scores was 3.2 (1.6). Almost all patients (98.5%) were prescribed with once daily dose of rivaroxaban, most commonly 20 mg (76.5%) and 15 mg (20.0%) as their initial treatment; 17.9% of patients received concomitant antiplatelet therapy. Most patients enrolled in RIVER met the recommended threshold for AC therapy (86.6% for 2012 ESC Guidelines, and 79.8% of patients according to 2016 ESC Guidelines).
Conclusions
The RIVER prospective registry will expand our knowledge of how rivaroxaban is prescribed in everyday practice and whether evidence from clinical trials can be translated to the broader cross-section of patients in the real world
Long-term magnesium orotate therapy in patients with mitral valve prolapse
Aim. To assess the effectiveness of long-term treatment with magnesium orotate (Magnerot®), as a pathogenetic therapy, in patients with mitral valve prolapse (MVP). Material and methods. In total, 31 MVP patients, administered Magnerot® (1500 mg/d) in three-month courses, twice a year, were followed up for 15 years. All patients underwent a complex clinical and instrumental examination which included clinical assessment, M-mode and B-mode echocardiography with simultaneous electrocardiography (ECG), standard 12-lead ECG at rest, 24-hour ECG monitoring, 24-hour blood pressure monitoring (BPM), and heart rate variability (HRV) assessment. Results. The study identified the specifics of clinical features, their association with the degree of phenotypical manifestation of connective tissue dysplasia, ECG changes, heart valve structure, autonomic homeostasis, BP levels and circadian profile, and sympathetic and parasympathetic tone. There was a significant reduction in mean and maximal heart rate, the number of tachycardia episodes, QTc interval duration, as well as the incidence of paroxysmal supraventricular tachycardia, supraventricular and ventricular extrasystolia. Maximal systolic and diastolic BP (SBP, DBP) levels, BP load, and initially increased SBP and DBP variability were significantly reduced. The retrospective analysis results showed a normalisation of the above-mentioned parameters in all participants. The sympathetic tone decreased, as demonstrated by a twofold reduction in the number of patients with sympathicotonia, a threefold increase in the number of participants with vagotonia, and a five-fold increase in the number of individuals with balanced sympathetic and parasympathetic tone. Conclusion. One-half of the examined MVP patients, who were administered a long-term Magnerot® therapy, have demonstrated a significant improvement in the treatment effectiveness index
Clinical effectiveness of magnesium orotate in patients with cardiac arrhythmias, arterial hypertension, and mitral valve prolapse
Aim. To evaluate the effectiveness of magnesium orotate in the patients with cardiac arrhythmias, arterial hypertension (AH), and idiopathic mitral valve prolapse (MVP). Material and methods. The complex examination, dynamic follow-up, and placebo-controlled differentiated treatment were performed in 84 patients with idiopathic MVP. All participants underwent echocardiography, 24-hour blood pressure monitoring (BPM) and electrocardiography (ECG) monitoring, office BP measurement, spectral analysis of heart rate variability (HRV), and physical stress test. The main group (MG; n=43) received magnesium orotate (3000 mg/d) for 6 months; the comparison group (CG; n=41) received placebo. Results. According to the 24-hour ECG monitoring data, the treatment was associated with disappearance of high-grade arrhythmias and a 40% reduction in supraventricular (paroxysmal and non-paroxysmal) tachycardia incidence. The number of ventricular extrasystoles was reduced in 26%, and they disappeared in 54%. In 8%, polytopic ventricular extrasystoles were substituted by occasional monotopic extrasystoles. These changes were not observed in the CG patients. The percentage of Stage I AH patients decreased from 38% to 8% in the MG, and from 30% to 20% in the CG. Conclusion. In MVP patients, magnesium orotate treatment improved electro-physiological heart parameters, with reduced supraventricular and ventricular extrasystole incidence and improved circadian BP profile
Alprazolam therapy effects on quality of life and vegetative dysfunction syndrome in patients with idiopathic mitral valve prolapse
Aim. To assess quality of life (QoL) and severity of vegetative dysfunction syndrome (VDS) in patients with idiopathic mitral valve prolapse (MVP); to evaluate the effects of alprazolam therapy on QoL and VDS. Material and methods. This single-blind, placebo-controlled study included 60 patients with idiopathic MVP (33,3% men, 66,7% women). All patients were randomised into two groups: the main group (MG), receiving alprazolam, and the control group (CG), receiving placebo. Both groups were comparable by age (mean age 30,8±0,4 and 31,1±0,2 years, respectively) and gender structure. In all patients with idiopathic MVP, organic internal pathology was ruled out. Both groups underwent complex examination at baseline and 10 weeks after the therapy started. Results. Clinically significant effectiveness of the treatment (VDS severity reduction (in points) by at least 50%, comparing to the baseline level) was observed among 80,0% of the patients receiving alprazolam (71,4% men, 82,6% women) and only in 33,3% (58,3% men, 16,7% women) of the controls. Alprazolam was clinically effective by the “DISS-work” scale in 30% (28,6% men, 30,4% women), by the “social life” scale – in 43,3% (57,1% men, 39,1% women), and by the “personal relationships” scale – in 56,7% (42,8% men, 60,9% women). In the placebo group, the respective percentages were 43,3% (50% men, 38,9% women), 30,0% (41,7% men, 22,2% women), and 46,7% (58,3% men, 38,9% women). Conclusion. Alprazolam therapy demonstrated significant QoL improvement and VDS severity reduction in patients with MVP
Antitumor and Antimetastatic Effect of Small Immunostimulatory RNA against B16 Melanoma in Mice.
Small interfering RNAs, depending on their structure, delivery system and sequence, can stimulate innate and adaptive immunity. The aim of this study was to investigate the antitumor and antimetastatic effects of immunostimulatory 19-bp dsRNA with 3'- trinucleotide overhangs (isRNA) on melanoma B16 in C57Bl/6 mice. Recently developed novel cationic liposomes 2X3-DOPE were used for the in vivo delivery of isRNA. Administration of isRNA/2X3-DOPE complexes significantly inhibits melanoma tumor growth and metastasis. Histopathological analysis of spleen cross sections showed hyperplasia of the lymphoid white pulp and formation of large germinal centers after isRNA/2X3-DOPE administration, indicating activation of the immune system. The treatment of melanoma-bearing mice with isRNA/2X3-DOPE decreases the destructive changes in the liver parenchyma. Thus, the developed isRNA displays pronounced immunostimulatory, antitumor and antimetastatic properties against melanoma B16 and may be considered a potential agent in the immunotherapy of melanoma