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PURPOSE: The development of the prediction methods of calcification risk of heart valve bioprostheses (BP) based on comprehensive assessment of the impact of clinical factors of the recipients and their adherence to medication. MATERIALS AND METHODS: We performed a retrospective study of clinical status and adherence to drug therapy of 170 recipients of heart valve BP with (n=63) and without (n=109) calcification. We used the method of comprehensive assessment of the analyzed parameters with estimation of prognostic coefficients for each of them, followed by calculation of integral indicators and construction on their basis of prognostic models for the various intervals of BP functioning. RESULTS: The most important risk factors of calcium-associated BP dysfunctions at any duration of observation were heart failure decompensation, as well as the discontinuation of ACE inhibitors and ß-blockers. At duration of BP functioning up to four years negative effect on prognosis produced the presence of concomitant multifocal atherosclerosis, during additional 4 (from 4 to 8) years - diabetes mellitus, and afterwards (over 8 years) - coronary artery disease. Lowering of probability of BP calcium degeneration was related to regular use of aldosterone antagonists during first 4 years after BP implantation and regular subsequent use of statins. CONCLUSIONS: Based on the comprehensive assessment of clinical status of patients and their compliance to medication it is possible to make adequate prediction models for assessment of the risk of structural dysfunctions due to BP calcification at various time intervals of remote postoperative period.
Assuntos
Bioprótese , Calcinose , Próteses Valvulares Cardíacas , Valvas Cardíacas , Humanos , Estudos RetrospectivosRESUMO
We studied leaching of Cu and Fe from naturally occurring chalcopyrite ore using aqueous solutions of ionic liquids (ILs) based on imidazolium and ethylammonium cations and hydrogensulfate, nitrate, acetate or dicyanamide anions. Liquid, solid and gas phases of the leaching systems were characterised. We have shown that nonoxidative leaching is greatly dependant not only on temperature and pH, but on the anion species of the IL. Solutions of 1-butylimidazolium hydrogen sulfate exhibited the best leaching performance among hydrogen sulphate ILs. We have suggested that the formation of an oxide layer in some ILs may be responsible for a reduced leaching ability. The analysis of the gas phase showed the production of CO2 and CS2 in all leached samples. Our results suggested that the CS2 produced upon leaching could be responsible for decreasing the sulfur, but not oxide, layer on the surface of chalcopyrite samples and therefore more efficient leaching. This is the first study, to our knowledge, to provide a systematic comparison of the leaching performance of ILs composed of different anions and cations and without added oxidants.
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The solubilities of the metal halides LiF, LiCl, LiBr, LiI, NaF, NaCl, NaBr, NaI, KF, KCl, KBr, KI, RbCl, CsCl, CsI, were measured at temperatures ranging from 298.15 to 378.15 K in the ionic liquid 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([C4C1im][OTf]). Li(+), Na(+) and K(+) salts with anions matching the ionic liquid have also been investigated to determine how well these cations dissolve in [C4C1im][OTf]. This study compares the influence of metal cation and halide anion on the solubility of salts within this ionic liquid. The highest solubility found was for iodide salts, and the lowest solubility for the three fluoride salts. There is no outstanding difference in the solubility of salts with matching anions in comparison to halide salts. The experimental data were correlated employing several phase equilibria models, including ideal mixtures, van't Hoff, the λh (Buchowski) equation, the modified Apelblat equation, and the non-random two-liquid model (NRTL). It was found that the van't Hoff model gave the best correlation results. On the basis of the experimental data the thermodynamic dissolution parameters (ΔH, ΔS, and ΔG) were determined for the studied systems together with computed gas phase metathesis parameters. Dissolution depends on the energy difference between enthalpies of fusion and dissolution of the solute salt. This demonstrates that overcoming the lattice energy of the solid matrix is the key to the solubility of inorganic salts in ionic liquids.
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PURPOSE: To assess significance of urinary neutrophil gelatinase-associated lipocalin (NGAL) for predicting hospital complications in subjects with ischemic heart disease (IHD) after coronary artery bypass grafting (CABG). MATERIALS AND METHODS: The study included 720 subjects who underwent CABG between 03/2011 and 04/2012. Blood serum creatinine level, glomerular filtration rate (GFR) (MDRD formula) and NGAL concentration were measured before and on day 7 after CABG. The following unfavorable outcomes of operative intervention: myocardial infarction (MI), stroke or transient ischemic attack, acute or progression of chronic renal disease, remediastinotomy were registered during in-hospital period. Additive EuroSCORE was calculated for all patients. RESULTS: There were no significant differences in serum creatinine level and GFR both before and on day 7 after CABG between groups of patients with different risk assessed by EuroSCORE, and with complicated and uncomplicated postoperative course. Urine NGAL level before and on day 7 after CABG was significantly higher in high and medium compared with low EuroSCORE risk groups. Preoperative NGAL urine level was significantly higher in patients with than in those without MI or stroke after CABG. NGAL urine level was also higher in patients with development of acute renal failure (ARF) compared with those without ARF. Both pre- and postoperative NGAL urine levels were higher in patients with unfavorable outcome while there were no significant differences in serum creatinine levels and CRF between patients with favorable and unfavorable outcomes. CONCLUSION: Preoperative measurement of urinary NGAL - a preclinical marker of acute kidney injury - allowed to predict more accurately the hospital risk of development of adverse cardiovascular and renal complications of CABG.
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Ponte de Artéria Coronária , Doença da Artéria Coronariana/cirurgia , Lipocalinas/urina , Injúria Renal Aguda/etiologia , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/urina , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/etiologia , Complicações Pós-Operatórias , Período Pós-Operatório , Acidente Vascular Cerebral/etiologiaRESUMO
Current data on structural--functional features of plant peroxidases and their involvement in functioning of the pro-/antioxidant system responding to stress factors, especially those of biotic origin, are analyzed. The collection of specific features of individual isoforms allows a plant to withstand an aggressive influence of the environment. Expression of some genes encoding different isoperoxidases is regulated by pathogens (and their metabolites), elicitors, and hormone-like compounds; specific features of this regulation are considered in detail. It is suggested that isoperoxidases interacting with polysaccharides are responsible for a directed deposition of lignin on the cell walls, and this lignin in turn is concurrently an efficient strengthening material and protects the plants against pathogens.
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Peroxidases/metabolismo , Plantas/enzimologia , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Interações Hospedeiro-Patógeno , Lignina/metabolismo , Peroxidases/química , Peroxidases/classificaçãoRESUMO
Solvatochromic transition metal (TM)-complexes with weakly associating counter-anions are often used to evaluate traditional neutral solvent and anion coordination ability. However, when employed in ionic liquids (IL) many of the common assumptions made are no longer reliable. This study investigates the coordinating ability of weakly coordinating IL anions in traditional solvents and within IL solvents employing a range of solvatochromic copper complexes. Complexes of the form [Cu(acac)(tmen)][X] (acac = acetylacetonate, tmen = tetramethylethylenediamine) where [X]- = [ClO4]-, Cl-, [NO3]-, [SCN]-, [OTf]-, [NTf2]- and [PF6]- have been synthesised and characterised both experimentally and computationally. ILs based on these anions and imidazolium and pyrrolidinium cations, some of which are functionalised with hydroxyl and nitrile groups, have been examined. IL-anion coordination has been investigated and compared to typical weakly coordinating anions. We have found there is potential for competition at the Cu-centre and cases of anions traditionally assigned as weakly associating that demonstrate a stronger than expected level of coordinating ability within ILs. [Cu(acac)(tmen)][PF6] is shown to contain the least coordinating anion and is established as the most sensitive probe studied here. Using this probe, the donor numbers (DNs) of ILs have been determined. Relative donor ability is further confirmed based on the UV-Vis of a neutral complex, [Cu(sacsac)2] (sacsac = dithioacetylacetone), and DNs evaluated via23Na NMR spectroscopy. We demonstrate that ILs can span a wide donor range, similar in breadth to conventional solvents.