29 research outputs found

    Sensing activity of cholinesterases through a luminescence response of the hexarhenium cluster complex [{Re<inf>6</inf>S<inf>8</inf>}(OH)<inf>6</inf>]<sup>4-</sup>

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    © 2016 The Royal Society of Chemistry.The present work describes a new method to sense cholinesterase-catalyzed hydrolysis of acetylcholine (ACh) through a luminescence response of the hexarhenium cluster complex [{Re6S8}(OH)6]4-. A proton released from acetylcholinesterase (AChE)- or butyrylcholinesterase (BuChE)-catalyzed hydrolysis of ACh results in time-resolved sensitization of cluster-centered luminescence. The sensitization results from protonation of apical hydroxo-groups of the cluster complex. The protonation is affected by a counter ion effect. Thus, optimal conditions for adequate sensing of acetic acid produced by ACh hydrolysis are highlighted. Time-resolved luminescence and pH measurements under conditions of AChE-catalyzed hydrolysis of ACh show a good correlation between the cluster-centered luminescence and pH-induced inhibition of AChE. The inhibition is not significant within the first two minutes of ACh hydrolysis. Thus, the luminescence response measured within two minutes is dependent on both substrate and enzyme concentrations, which fits with AChE and BuChE kinetics. The usability of cluster-centered luminescence for monitoring the concentration-dependent inhibition of AChE with irreversible inhibitors is demonstrated, using a carbamylating agent, pyridostigmine bromide, as a model

    COMPLICATED DIAGNOSIS: RETROPERITONEAL ALVEOCOCCOSIS IN THE GUISE OF ORMOND’S DISEASE

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    Diagnosis of parasitic diseases, in a type of their rarity and diversity, always presents considerable difficulties. Clinical observation of an alveococcosis with invasion in the retroperitoneal space with distribution on mediastinal fat proceeding with progressing retroperitoneal fibrosis with ureteral obstruction and hydronephrosis development, with an aorta lumen stenosis, with formation of SVC syndrome in the absence of changes in other parts of the body, first of all in the liver, in the absence of eosinophilia in the peripheral blood throughout all disease and lack of antibodies to echinococci in the blood serum, twice during observation determined by an immunofermental method is presented in this article

    Diverse effect of PEO-PPO-PEO and PPO-PEO-PPO triblock copolymers on temperature responsive behavior of luminescent hard-soft colloids

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    The present work introduces the interaction of hard and soft colloids in aqueous solutions at various temperatures and concentrations, as well as at critical conditions of temperature induced phase separation. Hard and soft colloids are represented by luminescent silica nanoparticles and aggregates of PEO-PPO-PEO and PPO-PEO-PPO triblock copolymers correspondingly. The formation of the mixed aggregates between hard and soft colloids in equilibrium conditions has been revealed by dynamic light scattering measurements. The distribution of silica nanoparticles between aqueous and surfactant rich phases after phase separation highlights the effect of pH, architecture and concentration of triblock copolymers on the mixed hard-soft colloids aggregation at cloud point conditions. The peculiar aggregation and phase behavior of PPO-PEO-PPO pluronics should be assumed as the main reason of the enhanced mixed aggregation with SNs at increased temperatures and concentrated conditions. © 2011 Elsevier B.V

    Diverse effect of PEO-PPO-PEO and PPO-PEO-PPO triblock copolymers on temperature responsive behavior of luminescent hard-soft colloids

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    The present work introduces the interaction of hard and soft colloids in aqueous solutions at various temperatures and concentrations, as well as at critical conditions of temperature induced phase separation. Hard and soft colloids are represented by luminescent silica nanoparticles and aggregates of PEO-PPO-PEO and PPO-PEO-PPO triblock copolymers correspondingly. The formation of the mixed aggregates between hard and soft colloids in equilibrium conditions has been revealed by dynamic light scattering measurements. The distribution of silica nanoparticles between aqueous and surfactant rich phases after phase separation highlights the effect of pH, architecture and concentration of triblock copolymers on the mixed hard-soft colloids aggregation at cloud point conditions. The peculiar aggregation and phase behavior of PPO-PEO-PPO pluronics should be assumed as the main reason of the enhanced mixed aggregation with SNs at increased temperatures and concentrated conditions. © 2011 Elsevier B.V

    Application of space imagery for express-evaluation of soil degradation in Ukrainian Polissia

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    4. Применение ГИС-технологий для почвенного картографирования и менеджмента земел

    Diverse effect of PEO-PPO-PEO and PPO-PEO-PPO triblock copolymers on temperature responsive behavior of luminescent hard-soft colloids

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    The present work introduces the interaction of hard and soft colloids in aqueous solutions at various temperatures and concentrations, as well as at critical conditions of temperature induced phase separation. Hard and soft colloids are represented by luminescent silica nanoparticles and aggregates of PEO-PPO-PEO and PPO-PEO-PPO triblock copolymers correspondingly. The formation of the mixed aggregates between hard and soft colloids in equilibrium conditions has been revealed by dynamic light scattering measurements. The distribution of silica nanoparticles between aqueous and surfactant rich phases after phase separation highlights the effect of pH, architecture and concentration of triblock copolymers on the mixed hard-soft colloids aggregation at cloud point conditions. The peculiar aggregation and phase behavior of PPO-PEO-PPO pluronics should be assumed as the main reason of the enhanced mixed aggregation with SNs at increased temperatures and concentrated conditions. © 2011 Elsevier B.V

    EXPERIMENTAL RATIONALE FOR THE USE OF ROPRENE TO PREVENT ISONIAZID-INDUCED LIVER DAMAGES

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    A model of isoniazid-induced liver damage in fast (females) and slow (males) acetylators was used to study the preventive hepatoprotective effect of the novel drug roprene in doses of 10, 15, and 30 mg/kg as an oil solution. It was found that in terms of a set of biochemical and morphological criteria, the most marked hepatoprotective effect of roprene given in a dose of 10 mg/kg and particularly 30 mg/kg was seen in the fast acetylators. In terms of morphological criteria for assessment, the most pronounced hepatoprotective effect of roprene used in a dose of 10 mg/kg and especially 30 mg/kg was observed in the slow acetylators. According to biochemical parameters, there was no advantage of any of the used doses (10, 15, and 30 mg/kg) of roprene in their effect on altered parameters. There is experimental evidence that it is advisable to use roprene to prevent isoniazid-induced hepatotoxicity in the patients with tuberculosis, primarily in the fast acetylators

    Study of effectiveness of antiviral drugs (umifenovir, triazavirin) against acute respiratory viral infections

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    Aim. Comparative study of clinical efficacy and safety of antiviral drug triazavirin and umifenovir in the treatment of patients with acute respiratory viral infections and influenza. Methods. The study included 100 patients aged 18 to 65 years diagnosed with moderate acute respiratory viral infection. Group 1 included 34 patients receiving umifenovir 200 mg 4 times a day for 5 days, and comparison group included 32 patients who received triazavirin 1 capsule (250 mg) 3 times a day for 5 days. Group 3 (control group) included 34 patients not treated with antiviral therapy. Efficacy and safety of the studied antiviral drugs were evaluated based on clinical symptoms in the disease course and were confirmed by adaptive reactions of the organism. Results. Among patients receiving triazavirin, recovery time and fever, headache and catarrhal syndrome resolution time were less than among patients who received umifenovir. On triazavirin treatment with favorable tolerability, symptomatic medications (antipyretics) were discontinued, and the duration of their use was less, than in patients receiving umifenovir. Evaluation of clinical efficacy of umifenovir and triazavirin for the treatment of acute respiratory viral infections and influenza demonstrated that the drugs effectively reverse the main symptoms of the disease (p <0.05), reduce complications incidence (18.1±2.1% vs. 55.9±3.2%, p <0.05) and contribute to the stabilization of adaptive reactions of the organism in contrast to the results of patients not receiving etiotropic therapy (6.9±2.9% vs. 12.8±2.7, p <0.05). During the use of umifenovir by day 4 and during the use of triazavirin by day 3 intoxication and catarrhal syndromes had been reversed, while in case of the absence of antiviral therapy, 55.8% of patients had continuing intoxication and catarrhal symptoms. Conclusion. The results of the study allow defining umifenovir and triazavirin as the first line of defense against acute respiratory viral infections with good efficacy and tolerability of the drugs
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