One of the most important pathological consequences of renal ischemia/reperfusion (I/R) is kidney malfunctioning. I/R leads to oxidative stress, which affects not only nephron cells but also cells of ...the vascular wall, especially endothelium, resulting in its damage. Assessment of endothelial damage, its role in pathological changes in organ functioning, and approaches to normalization of endothelial and renal functions are vital problems that need to be resolved. The goal of this study was to examine functional and morphological impairments occurring in the endothelium of renal vessels after I/R and to explore the possibility of alleviation of the severity of these changes using mitochondria-targeted antioxidant 10-(6′-plastoquinonyl)decylrhodamine 19 (SkQR1). Here we demonstrate that 40-min ischemia with 10-min reperfusion results in a profound change in the structure of endothelial cells mitochondria, accompanied by vasoconstriction of renal blood vessels, reduced renal blood flow, and increased number of endothelial cells circulating in the blood. Permeability of the kidney vascular wall increased 48 h after I/R. Injection of SkQR1 improves recovery of renal blood flow and reduces vascular resistance of the kidney in the first minutes of reperfusion; it also reduces the severity of renal insufficiency and normalizes permeability of renal endothelium 48 h after I/R. In
in vitro
experiments, SkQR1 provided protection of endothelial cells from death provoked by oxygen–glucose deprivation. On the other hand, an inhibitor of NO-synthases, L-nitroarginine, abolished the positive effects of SkQR1 on hemodynamics and protection from renal failure. Thus, dysfunction and death of endothelial cells play an important role in the development of reperfusion injury of renal tissues. Our results indicate that the major pathogenic factors in the endothelial damage are oxidative stress and mitochondrial damage within endothelial cells, while mitochondria-targeted antioxidants could be an effective tool for the protection of tissue from negative effects of ischemia.
The coupled development of aerodynamic asymmetry and hysteresis of the aerodynamic characteristics of an aircraft model with the straight wing (zero sweepback wing) of high aspect ratio λ = 10.6 is ...experimentally studied when the angle of attack varies from 0 to 20° and vice versa. The appearance of hysteresis is accompanied by the asymmetric flow separation from the wing panels. An increase in the Reynolds number Re from 0.24 × 10
6
to 0.32 × 10
6
leads to strengthening of the hysteresis effects. It is shown that the asymmetric deflection of ailerons by 40° and/or spoilers by –60° can lead to disappearance of asymmetry or change in its sign.
The possible application of the results of numerical modeling in developing an approximate phenomenological mathematical aerodynamic model applicable in solving the problems of dynamics is studied ...with reference to the example of the unsteady flow past the NACA 0015 airfoil oscillating in the angle of attack at different frequencies, amplitudes, and mean angles of attack. For this purpose, the Reynolds equations are solved in both steady and unsteady formulations, together with the
k
–ω SST turbulence model. The results of the calculations are validated by means of comparing them with the experimental data. The model of the normal force and the longitudinal moment formulated within the framework of an approach introducing an internal dynamic variable is identified according to the data of calculations. The results of the modeling are compared with the numerical and experimental data. The comparison with the conventional approach to the modeling based on the linear unsteady model with the use of dynamic derivatives is also carried out.
The occurrence of Mediterranean fever with periods of increase and decrease has been recorded in the Crimean peninsula. The city of Sevastopol and its vicinity are known endemic areas for this ...disease. Some of the most active agents in the spread of this rickettsiosis are feral and abandoned dogs. The aim of this study was to test ticks parasitizing dogs in Sevastopol for the presence of Rickettsia using molecular methods. The testing of ticks was carried out using real-time PCR and the ‘Real Best DNA Rickettsia species’ kit (AO ‘Vector-Best’) followed by sequence identification of the rickettsial DNA detected. The DNA marker for Rickettsia species (a conservative area of citrate synthase gene, gltA) was detected in 16 of 84 (19.1%) samples of Rhipicephalus sanguineus ticks tested. Larger fragments of gltA, ompA and sca4 were amplified and sequenced for 10 of 16 PCR-positive samples. Rickettsia DNA amplified from eight of the samples matched the sequence of Rickettsia conorii conorii Malish, the causative agent of Mediterranean fever. The sequences of Rickettsia DNA from two other ticks had the closest match to homologous fragments of Rickettsia massiliae, a pathogenic spotted fever rickettsia that was identified in the Crimean Peninsula for the first time as part of this study. The detection of two pathogenic species of Rickettsia in the studied ticks suggests the potential for two rickettsial diseases in the region and warrants further epidemiological and clinical studies.
Results of an experimental study of the hysteresis of aerodynamic characteristics of NACA 0018 airfoil in the T-124 low-turbulent wind tunnel of low subsonic speeds of TsAGI are reported. The ...experiments were carried out on the OVP-124 dynamic setup under steady-state conditions, under quasi-static (continuous) increase and decrease of the angle of attack, and with forced oscillations of the model over pitch with different amplitudes and frequencies relative to various set angles of attack. In all cases, measured aerodynamic characteristics exhibits a hysteresis related with the presence of a range of attack angles in which stable, non-unique separated-flow structures are observed. On the basis of experimental data obtained, a new approach to the mathematical modeling of the phenomenon of static and dynamic hysteresis of aerodynamic characteristics is developed for use in dynamics problems.
Secondary prevention should be actively implemented at all stages of treatment and rehabilitation of patients after acute coronary syndrome (ACS). The integration of remote monitoring of patients ...with the transfer of vital and laboratory data into clinical practice seems promising.
Aim.
To evaluate the clinical and patient-centered effectiveness of the original 12-month combined face-to-face and telecare program in patients with recent ACS.
Material and methods
. For the present analysis the data from 84 (out of 100) patients (median age, 56 (50;61) years, 70 males) was used. These patients had to have hypertension and/or type 2 diabetes and an ACS with percutaneous revascularization within 12 months. Their low-density lipoprotein cholesterol (LDL-C) had to be above 2,4 mmol/L. Telehealth program supplemented routine care. A program contained electronic self-control diaries for blood pressure (BP) and lipid profile, and teleconsulting service (text chat). Mandatory face-to-face visits were carried out at 3 and 12 months after the enrollment. The primary end point was ∆LDL-C. Additional clinical and patient-specific endpoints were evaluated.
Results.
At the 12-month visit, there was a significant decrease in LDL-C by 1,6 (-2,3;-0,9) mmol/L. Besides the initial LDL-C value, the decrease in LDL-C was associated with the proper adherence to keeping diaries of BP and lipid profile (β=0,7), and the number of text messages sent by the doctor in the 1st month after the enrollment (β=0,04). In more adherent patients, the ∆LDL-C was greater by 0,49 mmol/L (95% CI (-1,2; -0,1)) after adjustment for abovementioned covariates. In 35 patients (42%), target LDL-C was achieved, in 60 patients (71%) — a decrease ≥1 mmol/l. Other lipids also have changed for the better. Moreover, adherent patients were twice as likely to achieve the target LDL-C (OR 2,2; 95% CI (0,6; 3,8)) than non-adherent ones. A decrease in office systolic BP by 5,8 mm Hg was shown (p=0,03). The number of physician-to-patient messages exceeded those from patients to physician (median 143 and 111 per patient for 12 months, respectively). The quality of life has improved, but only in terms of emotions. Satisfaction with the program remained high at all timepoints of the study.
Conclusion.
Our study showed the effectiveness of the integrated care in ACS patients with the telehealth tool included. Commitment to BP self-monitoring, as well as active consultative support at the first stages of rehabilitation, contributes to additional dynamic control of lipid profile, timely correction of lipid-lowering therapy with the achievement of the target LDL-C level. Most of the patients did not experience any difficulties in using the program and are ready to recommend integrated approach to other peers.
The effect of γ-radiation on the optical properties of layered TlGaSe
2
and TlInS
2
crystals has been studied within a wavelength range of 400–1100 nm at 300 K. By means of analysis of optical ...absorption spectra, the energies of direct and indirect optical interbend transitions before and after γ-irradiation have been determined. It has been shown that the energies of direct and indirect nonforbidden optical transitions grow with accumulation of γ-radiation dose within 0–25 Мrad in TlGaSe
2
and TlInS
2
single crystals from
E
gd
= 2.06 eV and
E
gi
= 1.90 eV at
D
= 0 Мrad to
E
gd
= 2.11 eV and
E
gi
= 1.98 eV at
D
= 25 Мrad for TlGaSe
2
crystals and from
E
gd
= 2.32 eV and
E
gi
= 2.27 eV at
D
= 0 Мrad to
E
gd
= 2.35 eV and
E
gi
= 2.32 eV at
D
= 25 Мrad for TlInS
2
crystals. A decrease in the transmission coefficient at doses from 0 to 5 Mrad with a further increase in the transmission coefficient at a radiation dose of
D
= 25 Мrad is observed.
The effects of septoplasty and sinus lifting simulation in rats on changes in the frequency domain of heart rate variability were compared. In the early postoperative period, the low-frequency ...component increases, and the high-frequency component decreases. The VLF range also increased. This indicates an increase in the activity of the sympathetic nervous system and a shift in metabolism under the influence of post-surgical inflammation.
Esters of vicinal dicarboxylic acids are synthesized. Their structural specifics are studied. The thermooxidative stability of the vicinal dicarboxylic acid esters is estimated. It is established by ...IR spectroscopy that the oxidation proceeds along the C–H bond of a tertiary carbon atom. The C=C bond of alkenes does not participate in the oxidation process.
Giant macroscopic expansion of the surface relief, localized within a laser spot size, has been observed in bulk single crystals of TlInSe
2
, TlGaTe
2
, and TlSe at room temperature and laser ...radiation densities lower by at least two orders of magnitude than the material optical damage threshold. Quantitative estimations of the deformation magnitude in this local region were obtained using an interference dilatometer. The photon absorption length was determined with the aid of spectroscopic ellipsometry. It is established that the surface deformation amounts to 2.6 × 10
–3
at a laser radiation intensity of 19 mW/mm
2
. The observed phenomenon has a thermal nature and is probably related to a low thermal conductivity of the materials studied.
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