Use of one- and two-mediator systems for developing a BOD biosensor based on the yeast Debaryomyces hansenii.

We investigated the use of one- and two-mediator systems in amperometric BOD biosensors (BOD, biochemical oxygen demand) based on the yeast Debaryomyces hansenii. Screening of nine mediators potentially capable of electron transfer - ferrocene, 1,1'-dimethylferrocene, ferrocenecarboxaldehyde, ferroceneacetonitrile, neutral red, 2,6-dichlorophenolindophenol, thionine, methylene blue and potassium ferricyanide - showed only ferrocene and neutral red to be efficient electron carriers for the eukaryotes studied. Two-mediator systems based on combinations of the investigated compounds were used to increase the efficiency of electron transfer. The developed two-mediator biosensors exceeded their one-mediator analogs by their characteristics. The most preferable two-mediator system for developing a BOD biosensor was a ferrocene-methylene blue combination that ensured a satisfactory long-time stability (43 days), selectivity, sensitivity (the lower limit of the determined BOD5 concentrations, 2.5mg О2/dm3) and speed (assay time for one sample, not greater than 10min) of BOD determination. Analysis of water samples showed that the use of a ferrocene-methylene blue two-mediator system and the yeast D. hansenii enabled registration of data that highly correlated with the results of the standard method (R=0.9913).

[The detection of 2-nitroaniline and 2-nitro-4-methylaniline in the biological materials].

We have determined the optimal conditions for the extraction of 2-nitroaniline and 2-nitro-4-methylaniline in the biological material with acetone. Moreover, this study has demonstrated the possibility of purification of the extracts thus obtained and containing co-extracted components of the biological material by low-pressure chromatography on Silasorb C-18 columns with the particle size of 30 mcm. The modified methods of thin-layer chromatography and high performance liquid chromatography are proposed for the isolation and identification of 2-nitroaniline and 2-nitro-4-methylaniline from the extracts of cadaveric liver tissue.

[Analysis of the natural course of fibrosing alveolitides: from district therapist to specialized pulmonology unit].

Fibrosing alveolitides (FA) are common diseases, as yet insufficiently known to practitioners. In most cases, objective and subjective difficulties arise in diagnosing FA in the outpatient setting. The course of FA has been analyzed in 48 patients from their first visit to a polyclinic to admission to a specialized pulmonology unit. There is a high rate of outpatient diagnostic errors that may be accounted for by the similarity of many lung diseases, at their onset in particular, by small-scale studies and district therapists' little experience in working with patients with FA. The results of comprehensive examinations of patients with FA in a specialized clinic are given.

[The effectiveness and safety of accessory treatment with vobenzyme in patients with community-acquired pneumonia].

The effectiveness and safety of treatment with vobenzyme supplemented to the standard antibiotic therapy have been compared in 60 patients. Addition of vobenzyme to the standard antibiotic therapy significantly reduces the number and degree of respiratory symptoms has a pronounced effect on the activity of inflammation, leads to a more complete reversal of pulmonary parenchymatous infiltration on a roentgenogram, contributes to the achievement of the maximum efficiency of treatment, and substantially diminishes residual respiratory symptoms of pneumonia economically expediently and safety at a late follow-up.