36 research outputs found
Prognostic value of vascular remodeling parameters in the development of adverse cardiovascular events in patients with gastric cancer
Aim.Ā To determine a possible prognostic marker for adverse cardiovascular events in patients with gastric cancer by studying the early and long-term effects of multiagent chemotherapy (MAC) on the structural and functional vascular wall parameters.MaterialĀ andĀ methods. The study included 25 patients with newly diagnosed gastric cancer who received courses of chemotherapy with platinum-based agents and fluoropyrimidines. All patients before, immediately after MAC courses and in the long-term period underwent a non-invasive assessment of vascular wall and endothelial function (photoplethysmography (PPG)). In the survivorsā cohort, a correlation analysis was performed to assess the risk of future cardiovascular events depending on changes of PPG parameters.Results.Ā Before the MAC courses, cancer patients had endothelial dysfunction (mean occlusion index, 1,7 (1,4; 1,9), N>1,8) and structural vascular wall disorders (mean stiffness index, 8,9 m/s (7,7; 9,7), N<8 m/s, mean reflection index, 32,4% (27,5; 37,7), N<30%). All indicators significantly worsened after MAC in the form of endothelial dysfunction progression and vascular remodeling: mean occlusion index, 1,3 (1,2; 1,5) (p<0,0002), stiffness index, 10,3 m/s (9,5; 11,2) (p<0,0001), reflection index, 40,2% (35,5; 43,6) (p<0,001). Long-term follow-up averaged 2,9 years (2,3-3,7 years). All-cause and cardiovascular mortality was 32% and 12%, respectively. Nine patients developed a cardiovascular events (CVEs) (de novo, progression of prior CVD). Significant changes of vascular indicators in the long-term period was not revealed. A trend towards association between increased reflection index and a higher probability of cardiovascular pathology was revealed (OR 1,20, 95% CI 1,01-1,55, p=0,081).Conclusion. In this study, for the first time, a comprehensive assessment of the effect of MAC on endothelial dysfunction and vascular stiffness, including, in the long-term follow-up period, was carried out in patients with gastric cancer. A significant aggravation of all parameters of vascular remodeling immediately after treatment in the absence of their significant dynamics in the future has been proven. A possible prognostic marker, namely the reflection index, of an unfavorable cardiac outcome in patients with gastric cancer has been identified, which requires further study
Canonical description of ideal magnetohydrodynamic flows and integrals of motion
In the framework of the variational principle the canonical variables
describing ideal magnetohydrodynamic (MHD) flows of general type (i.e., with
spatially varying entropy and nonzero values of all topological invariants) are
introduced. The corresponding complete velocity representation enables us not
only to describe the general type flows in terms of single-valued functions,
but also to solve the intriguing problem of the ``missing'' MHD integrals of
motion. The set of hitherto known MHD local invariants and integrals of motion
appears to be incomplete: for the vanishing magnetic field it does not reduce
to the set of the conventional hydrodynamic invariants. And if the MHD analogs
of the vorticity and helicity were discussed earlier for the particular cases,
the analog of Ertel invariant has been so far unknown. It is found that on the
basis of the new invariants introduced a wide set of high-order invariants can
be constructed. The new invariants are relevant both for the deeper insight
into the problem of the topological structure of the MHD flows as a whole and
for the examination of the stability problems. The additional advantage of the
proposed approach is that it enables one to deal with discontinuous flows,
including all types of possible breaks.Comment: 16 page
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 Ī²-globulin (rS=0.43, p<0.05); LA EFact and neuregulin-1Ī² (rS=0.42, p<0.05); LA expansion index and neuregulin-1Ī² (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
Transition of an electromagnetically driven liquid metal flow from laminar to turbulent in a toroidal square duct
The electromagnetically driven liquid metal flow in a toroidal duct of a square cross-section is studied numerically searching for the critical Reynolds (Re) and Hartmann (Ha) numbers where transition occurs. Results are reported for Ha up to 500, building a transition map of critical Reynolds and Hartmann numbers and showing two distinct regimes of transition signified by the destabilization of the secondary flow: The first, for Ha = 18, where it is balanced by fluid inertia. In both cases, the destabilization of the secondary flow occurs primarily near the concave sidewall. For Ha >= 18 the transition follows approximately the relationship Re = 16.803 Ha(1.43) for values of Re and Ha in the range 80 < Re/Ha < 224. Copyright (C) EPLA, 201
Equations of Plasma Equilibrium in a Magnetic Field with Three-Dimensional Magnetic Surfaces
INFLUENCE OF THE COMBINATION DRUG PRESTANS (PERINDOPRIL A, AMLODIPINE) ON MORPHO-FUNCTIONAL PARAMETERS OF ARTERIAL BED IN ESSENTIAL HYPERTENSION
Aim. Recently, the problem of endothelial dysfunction is in high interest. It was proved that microcirculatory disorders play main role in development and progression of target organ damage in essential arterial hypertension (EAH). Microcirculatory bed itself should be the target of EAH. Modern antihypertension drugs, despite of normalization of blood pressure (BP), should fulfill the prevention of target organ damage. In our study, the influence was evaluated, of treatment with the fixed combination of perindopril A and amlodipine (PrestansĀ®, āLes Laboratoires Servierā, France) on structural and functional parameters of the heart and vessels.Material and methods. In the study, 30 patients with grade II-III EAH included, mean age 54,12Ā±9,15 y.o., duration of EAH ā 12,6 (4;21) years. For the assessment of endothelial function and structural and functional condition of capillary net of a finger skin, photopletysmography were applied and videocapillroscopy, respectively.Results. Therapy with PrestansĀ® led to improvement of functioning of the middle sized vessels and microcirculatory vessels (MC) (increase of occlusion index on MC level from 1,5 to 1,8, p<0,006); on the large vessels level led to phase shift from 6,0 to 10,3 (Ń<0,00005). There was influence of PrestansĀ® on the parameters characterizing vascular bed remodelling on the levels of cappilars: density of capillary net in the skin at rest (cap/mm2) increased from 47 cap/mm2 to 51 cap/mm2 (Ń<0,00005), and the density of capillar net after venous occlusion test ā from 53 cap/mm2 to 60 cap/mm2 (Ń<0,006).Conclusion. PrestansĀ® is a medication of choice not only for AH treatment, but for prevention of target organs damage, that is based on correction of endothelial dysfunction and morphofunctional parameters at the level of MC
Metabolic Syndrome: Development of the Issue, Main Diagnostic Criteria
Obesity is one of the leading and the most serious risk factors of cardiovascular diseases. Overweight provokes many metabolic and hemodynamic disorders.Ā About 30% of inhabitants of the planet have overweight and prevalence of obesity increases by 10% every 10 years according to the WHO data.Ā The probability of arterial hypertension in obeseĀ patients is 50% higher than in people with normal body mass. Framingham study showed that obesity is an independent, significant risk factorĀ of ischemic heartĀ disease, myocardial infarction, cerebral strokeĀ andĀ diabetes mellitus. The most dangerous is the central obesity with the preferential fat deposition in the abdomen. Combination of visceral obesity, violation of carbohydrate and lipid metabolism, arterial hypertension, and close pathogenic relationship between theseĀ factorsĀ underlie the isolated symptom complex knownĀ as metabolic syndrome. J. Vague was the first to describe relationship between abdominal obesity with cardiovascular disease and mortality in 1947. In our country G.F. Lang noticed common combination of arterial hypertension with obesity, lipid and carbohydrate metabolism disorders. Thus, metabolic syndrome significantly increases risk andĀ severity of cardiovascular disease. Within last decades criteria of metabolic syndrome stays constant. The factorsĀ of insulin resistance andĀ endothelial dysfunction as stages of the pathogenesis of the metabolic syndrome have beenĀ studied in detail. The mechanisms of insulin resistance and endothelial dysfunction are discussed in detail in this article as well as inflammatory markers and the significance of highly sensitive C-reactive protein