Effect of Biocides on the Activity of Extracellular Enzymes Produced by Degrader Fungi from Technical Objects Used in Tropical Climates (Vietnam).

Activity of extracellular enzymes was assessed in 20 strains of microscopic fungi involved in biodegradation of technical objects exploited under tropical climate conditions (Vietnam). It was found that 19 strains possessed catalase activity, 18 strains had phenol oxidase activity, and eight strains had protease activity. The effect of industrial biocides on the activity of these enzymes was also assessed. The biocides Bior-1, Bioneutral A 10, and Bioneutral A 101 were shown to inhibit the enzymatic activity to various extent. All biocides inhibited extracellular catalase activity in most fungal strains studied. The inhibition of protease and phenol oxidase activity of same test strains was less pronounced. The response to biocides varied at the strain level; its characteristics could differ significantly even between strains of the same species. In several cases, it was observed that exposure to biocides resulted in an increase in enzyme activity.

[Role of superoxide anion radicals in the bacterial corrosion of metals].

It was found that seven strains of bacteria can cause corrosion damage to aluminum, its alloys, and zinc. With respect to the studied metals, the most active bacteria were Proteus vulgaris 1212 and Pseudomonas aeruginosa 969. Superoxide anion radicals were demonstrated to play a role in the initiation of corrosive damage to aluminum and zinc, while bacterial exometabolites participate in the later stages of this process.

[Microbiological corrosion of aluminum alloys].

Biological corrosion of ADO quality aluminum and aluminum-based construction materials (alloys V65, D16, and D16T) was studied. Thirteen microscopic fungus species and six bacterial species proved to be able to attack aluminum and its alloys. It was found that biocorrosion of metals by microscopic fungi and bacteria was mediated by certain exometabolites. Experiments on biocorrosion of the materials by the microscopic fungus Alternaria alternata, the most active biodegrader, demonstrated that the micromycete attack started with the appearance of exudate with pH 8-9 on end faces of the samples.

[The nutritional status of children in intensive care units].

The paper deals with the nutritional status of infants in intensive care units (ICU). It shows nutritional trends in 269 children aged 1 month to 15 years, treated in the ICU of a Tushino children's city hospital, Moscow, for brain injury, abdominal surgical diseases, and severe pneumonia. The paper evaluates the physical development of children in the ICU, shows the trends in weight-height, somatometric, laboratory parameters, and balance study data. The values of protein losses and nitrogen balance in children in the postaggression period and their relationship to age and feeding mode (enteral, parenteral-enteral) are shown.

[An algorithm for processing the data from the radionuclide angiography of the internal organs]. / Algoritm obrabotki dannykh radionuklidnoi angiografii vnutrennikh organov.

The paper is devoted to the theoretical substantiation and approaches to the determination of the main parameters of circulation of the internal organs on the basis of the results of indirect radionuclide angiography. Formulas for the calculation of circulation mean time, blood flow volumetric rate and its fraction of the cardiac output were given. Using algorithms, cited in the paper, one could prepare programs for the processing of radionuclide angiography data on computers.

[Assessment of the effective ejection fraction for the right and left ventricles based on radionuclide ventriculographic data]. / Otsenka éffektivnoi fraktsii vybrosa dlia pravogo i levogo zheludochkov po dannym radionuklidnoi ventrikulografii.

The authors proposed a method of the evaluation of the effective right and left ventricular ejection fraction on the basis of radionuclide ventriculography data. They substantiated theoretically this approach and gave formulas for ejection fraction calculation. Shortcomings of dynamic and static radioventriculography were discussed. This method could be used in clinical practice.

[Possibilities of using citon for examining the kidneys]. / Vozmozhnosti primeneniia tsitona dlia issledovaniia pochek.

To determine the area of application of citon, a radiopharmaceutical produced in Hungary, a study was made of its major pharmacokinetic properties with relation to the nature and rate of its release from the blood, selective renal excretion, the time of diffusing from the plasma and the time of passing through the kidneys. A total of 45 patients were examined with the help of a computerized gamma-chamber and renograph in the course of dynamic scintigraphy and renography. Analysing the data obtained on the basis of a chamber model of the indicator behavior, using appropriate processing of the recorded curves one can conclude that the behavior of citon differed little from that of other filtrating agents, such as 99mTc-DTPA.

[The action of different biocides on the phosphatase activity of Aspergillus niger]. / Issledovanie deistviia razlichnykh biotsidov na aktivnost' fosfataz Aspergillus niger.

Metalorganic and quarternary ammonium compounds when added to culture medium inhibited growth of Aspergillus niger mycelium and activity of neutral and alkaline phosphatase. A quarternary ammonium compound, ethonium, and a tin-organic compound, tributyl oxide, exerted an inhibiting effect on activity of acid phosphatase which amounted to 54% of the total phosphatase activity in mycelium and 94% in the culture liquid. The rest of biocides induced lysis of intracellular membranes, phosphatase release from lysosomas, which made acid phosphatase activity higher. Being introduced into the mycelium homogenate the above compounds inhibited activity of the acid phosphatase. The same biocides inhibited extracellular acid phosphatase in the culture liquid. Recommendations are given on the use of a number of substances as means for protection of industrial materials from biolesions.