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In this work, we primarily aimed to study the Nb(V) doping effect on the surface activity and optical and electrical properties of nanocrystalline TiO2 obtained through flame-spray pyrolysis. Materials were characterized using X-ray diffraction, Raman spectroscopy and IR, UV and visible spectroscopy. The mechanism of surface reaction with acetone was studied using in situ DRIFTs. It was found that the TiO2-Nb-4 material demonstrated a higher conversion of acetone at a temperature of 300 °C than pure TiO2, which was due to the presence of more active forms of chemisorbed oxygen, as well as higher Lewis acidity of the surface. Conduction activation energies (Eact) were calculated for thin films based on TiO2-Nb materials. The results of the MB photobleaching experiment showed a non-monotonic change in the photocatalytic properties of materials with an increase in Nb(V) content, which was caused by a combination of factors, such as specific surface area, phase composition, concentration of charge carriers as well as their recombination due to lattice point defects.
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Tachycardia-induced cardiomyopathy (TIC) is a reversible subtype of dilated cardiomyopathy (DCM) resulting from sustained supraventricular or ventricular tachycardia and diagnosed by the normalization of left ventricular ejection fraction (LVEF) after stable sinus rhythm restoration. The aim of this study was to determine the contribution of cardiac magnetic resonance (CMR) to the differential diagnosis of TIC and DCM with persistent atrial arrythmias in patients hospitalized for the first time with heart failure (HF) with reduced LVEF of nonischemic origin. A total of 29 patients (age: 58.2 ± 16.9 years; males: 65.5%; average EF: 37.0 ± 9.5%) with persistent atrial tachyarrhythmia and first decompensation of HF without known coronary artery diseases were included in this study. The patients successfully underwent cardioversion and were observed for 30 days. The study population was divided into groups of responders (TIC patients; N = 16), which implies achieving FF > 50% or its increase > 10% in 30 days of TIC, and non-responders (N = 13). The increase in left ventricle (LV) volumes measured using CMR was significantly higher in the non-responder group when compared with the responders (114.8 mL ± 25.1 vs. 68.1 mL ± 10.5, respectively, p < 0.05). Non-responders also demonstrated decreased interventricular septum thickness (9.1 ± 0.8 vs.11.5 ± 1.3, respectively, p < 0.05). Late gadolinium enhancement (LGE) was observed in 12 patients (41.4%). The prevalence of LGE was increased in the non-responder group (25.0% vs. 65.1%, respectively, p = 0.046). Notably, a septal mid-wall LGE pattern was found exclusively in the non-responders. Epicardial adipose tissue thickness was decreased in the non-responder group versus the TIC patients. Conclusion: Patients with TIC were found to have smaller atrial and ventricular dimensions in comparison to patients with DCM. In addition, LGE was more common in DCM patients.
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Biocompatible polyesters are widely used in biomedical applications, including sutures, orthopedic devices, drug delivery systems, and tissue engineering scaffolds. Blending polyesters with proteins is a common method of tuning biomaterial properties. Usually, it improves hydrophilicity, enhances cell adhesion, and accelerates biodegradation. However, inclusion of proteins to a polyester-based material typically reduces its mechanical properties. Here, we describe the physicochemical properties of an electrospun polylactic acid (PLA)-gelatin blend with a 9:1 PLA:gelatin ratio. We found that a small content (10 wt%) of gelatin does not affect the extensibility and strength of wet electrospun PLA mats but significantly accelerates their in vitro and in vivo decomposition. After a month, the thickness of PLA-gelatin mats subcutaneously implanted in C57black mice decreased by 30%, while the thickness of the pure PLA mats remained almost unchanged. Thus, we suggest the inclusion of a small amount of gelatin as a simple tool to tune the biodegradation behavior of PLA mats.
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Gelatina , Nanofibras , Ratones , Animales , Gelatina/química , Poliésteres/química , Andamios del Tejido/química , Materiales Biocompatibles/química , Ingeniería de Tejidos/métodos , Aceleración , Nanofibras/químicaRESUMEN
OBJECTIVE: To determine the impact of sodium-dependent glucose type 2 cotransporter inhibitors on the renal function in acute heart failure. METHODS: In a single-centre, controlled, randomised study, patients were prescribed dapagliflozin in addition to standard therapy, or were in receipt of standard therapy. The prespecified outcome was renal function deterioration; the secondary outcomes were the development of resistance to diuretics, weight loss, death during hospitalisation and the rehospitalisation or death for any reason within 30 days following discharge. RESULTS: 102 patients were included (73.4±11.7 years, 57.8% men). The average left ventricular ejection fraction was 44.9%±14.7%, the average N-terminal prohormone of brain natriuretic peptide (NT-proBNP) was 4706 (1757; 11 244) pg/mL, the average estimated glomerular filtration rate (eGFR) was 51.6±19.5 mL/min. eGFR decreased 48 hours after randomisation in the dapagliflozin group (-4.2 (-11.03; 2.28) mL/min vs 0.3 (-6; 6) mL/min; p=0.04) but did not differ between the groups on discharge (54.71±19.18 mL/min and 58.92±24.65 mL/min; p=0.36). The incidence of worsening renal function did not differ (34.4% vs 15.2%; p=0.07). In the dapagliflozin group, there was less tendency to increase the dose of loop diuretics (14% vs 30%; p=0.048), lower average doses of loop diuretics (78.46±38.95 mg/day vs 102.82±31.26 mg/day; p=0.001) and more significant weight loss (4100 (2950; 5750) g vs 3000 (1380; 4650) g; p=0.02). In-hospital mortality was 7.8% (4(8%) in the dapagliflozin and 4 (7.7%) in the control group (p=0.95). The number of deaths within 30 days following discharge in the dapagliflozin group and in the control group was 9 (19%) and 12 (25%), p=0.55; the number of rehospitalisations was 14 (29%) and 17 (35%), respectively (p=0.51). CONCLUSION: The use of dapagliflozin was associated with a more pronounced weight loss and less need to increase diuretic therapy without significant deterioration of the renal function. Dapagliflozin did not improve the in-hospital and 30-day prognosis after discharge. TRIAL REGISTRATION NUMBER: N04778787.
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Insuficiencia Cardíaca , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico , Compuestos de Bencidrilo , Diuréticos/efectos adversos , Femenino , Glucósidos , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Riñón/fisiología , Masculino , Proyectos Piloto , Inhibidores del Simportador de Cloruro Sódico y Cloruro Potásico/efectos adversos , Volumen Sistólico , Función Ventricular Izquierda , Pérdida de PesoRESUMEN
BACKGROUND/AIM: A series of experiments on HeLa cells were conducted to provide new information concerning the anti-cancer properties of jaspine B hydrochloride (JBH). MATERIALS AND METHODS: HeLa cells treated with 0.5 µmol/l JBH for 24, 48, and 72 h underwent flow cytometric analysis of the cell cycle, and measurement of phosphatidylserine externalization, mitochondrial membrane potential (MMP), casp-3 activation, cleavage of PARP, ceramide levels, aSMase activity, and Bcl-2 release. nSMase activity was measured by a colorimetric assay. Gene expression was determined by qRT-PCR. Immunocytochemistry was performed to detect p21 and p27 expression. RESULTS: JBH-induced apoptosis in HeLa cells associated with externalization of phosphatidylserine, reduced MMP, activation of casp-3, and cleavage of PARP as well as up-regulation of TNF-α, FasL, and casp-8. Significant increase in nSMase activity, ceramide levels, Bcl-2 release (predominantly in the inactive form), and pro-apoptotic nuclear localization of p21 and p27 were also detected. CONCLUSION: JBH-induced apoptosis in HeLa cells is associated with disrupted sphingolipid homeostasis resulting in increased ceramide levels.
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Apoptosis/efectos de los fármacos , Ceramidas/metabolismo , Esfingolípidos/metabolismo , Esfingosina/análogos & derivados , Proliferación Celular/efectos de los fármacos , Células HeLa , Humanos , Transducción de Señal/efectos de los fármacos , Esfingosina/farmacologíaRESUMEN
The morphology and proliferation of eukaryotic cells depend on their microenvironment. When electrospun mats are used as tissue engineering scaffolds, the local alignment of the fibers has a pronounced influence on cells. Here we analyzed the morphology of the patterned mats produced by electrospinning of PLA-gelatin blend onto a conductive grid. We investigated the cellular morphology and proliferation of two cell lines (keratinocytes HaCaT and fibroblasts NIH 3T3) on the patterned mats. The non-patterned mats of the same chemical composition were used as control ones. The HaCaT cells predominantly grew on convex areas of the patterned mats along with increasing their nucleus area and decreasing cell area. The 3T3 cells had a lower proliferative rate when grown on the patterned mats. The results can be valuable for further development of the procedures, which allow the patterned electrospun mats development as well as for the investigation of cell-substrate interactions.
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Gelatina , Ingeniería de Tejidos , Animales , Proliferación Celular , Ratones , Poliésteres , Andamios del TejidoRESUMEN
Biodegradable blended electrospun mats are promising for biomedical applications such as wound dressing, tissue engineering, and drug delivery. Electrospun mats based on polyesters can be modified by the addition of other polymers or proteins to accelerate the degradation, improve mechanical properties or biocompatibility. However, relatively little is known about the distribution of the components throughout the blended mats. In the present work, we prepared polylactide (PLA), bovine serum albumin (BSA), and the blended PLA-BSA electrospun mats. We demonstrated that PLA and BSA are miscible in a common solvent HFIP (1,1,1,3,3,3-hexafluoro-2-propanol) at concentrations below 3%, but become immiscible as concentration increases. We used three methods (fluorescence microscopy, EDX, and Raman microspectroscopy) to validate that PLA and BSA can be blended in a single electrospun fiber despite the phase separation in the blend. The homogeneity of the blend influences on the homogeneity of the distribution of PLA and BSA components throughout the electrospun mat, as measured by Raman microspectroscopy. When the blended electrospun mats were incubated in water, they demonstrated the prolonged release of BSA. The presented results show a step-by-step approach for manufacturing blended electrospun mats made of immiscible components, which involves the analysis of component miscibility, the mat morphology, and composition. This approach can be used for the rational design of multicomponent electrospun mats.
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The primary objective of this clinical study was to evaluate the effect of a dietary multivitamin, multimineral and phytonutrient (VMP) supplement on blood nutrient status and biomarkers of heart health risk in a Russian population. One hundred twenty healthy adults (40-70 years) were recruited for a 56-day (eight-week) randomized, double blind, placebo controlled study with parallel design. Subjects were divided into two groups and received either a VMP or a placebo (PLA) supplement. Blood nutrient levels of ß-carotene, α-tocopherol, vitamin C, B6, B12, red blood cell (RBC) folate, Zinc and Selenium were measured at baseline and on Days 28 and 56, and quercetin was measured at baseline and on Day 56. Blood biomarkers of heart health, i.e. homocysteine (Hcy), high-sensitivity C-reactive protein (hs-CRP), oxidized LDL (ox-LDL), gamma-glutamyl transferase (GGT), uric acid and blood lipid profile, were measured at baseline and Day 56. Dietary VMP supplementation for 56 days significantly increased circulating levels of quercetin, vitamin C, RBC folate and partially prevented the decline in vitamin B6 and B12 status. Both serum Hcy and GGT were significantly reduced (-3.97 ± 10.09 µmol/L; -1.68 ± 14.53 U/L, respectively) after VMP supplementation compared to baseline. Dietary VMP supplementation improved the nutrient status and reduced biomarkers of heart health risk in a Russian population.