Comparative insecticidal acitvity of sumithrin and neopinamine.

The examination of insecticidal properties of the new pyrethroid--sumithrin--showed this compound in contact action to be a highly effective insecticide, superior in activity to neopinamine. The intestinal action of sumithrin is less pronounced in comparison with neopinamine. Sumithrin is more selective in its effect on insects as compared with neopinamine. In the form of earosols, sumithrin and its mixtures with DDVP are less active than compositions based on neopinamine.

[Insecticidal properties of sumitrin]. / Insektitsidnye svoistva sumitrina

The study of insecticidal properties of sumitrin demonstrated that in contact action it was a highly effective insecticide; in topical application LD50 for domestic flies, bedbugs and cockroaches was 0.47, 1.25 and 3.26 mug/g, respectively. Sumitrin possessed high action selectivity for insects and low toxicity for warm-blooded animals (LD50 for albino mice greater than 7500 mg/kg). In the form of aerosols sumitrin and its mixtures with DDVF were less active than compositions on the neopinamine base.

[Use of rooms with laminar air flow]. / Ispol'zovanie boksov s laminarynym potokom vozdurha

The paper deals with the problem of dependency of the reduction of microbial contamination and of dust pollution of the air mediu min the CAMERA-BOXES with a liminary flux on the aeration degree. It was shown that the degree of aeration in the camera-box constituted from 330 to 1060, with the rate of the air flux at the filter exit of from 0.2 to 0.6 m/sec. Vertical laminar flux provided release of the air from the microbes and dust. The use of the camera-box with a laminar flux for work requiring sterile conditions is recommended.

Effect of extreme factors on micro-organisms used for the control of the effectiveness of sterilization.

Survival of micro-organisms used for control of sterilization procedures was studied under conditions simulating the Martian environment (daily temperature change from +20 degrees to -20 degrees in 99.98% CO2 + 0.02% air at 0.13 x 10(-6) N m-2 pressure, with ultraviolet radiation spanning the whole range of the solar spectrum 300-350 MkW cm-2). The test organisms were four strains of Bacillus subtilis and one strain of Bacillus anthracoides, and were inoculated on to four materials, smooth metal, porous plastic, multilayer composition material and powdered limonite. Some organisms survived on all materials, the greatest on the limonite. The resistance of the survivors to disinfectants was the same as that of the original cultures.

[Disinfection of medical orthopedic articles made of polymer materials]. / Nekotorye voprosy dezinfektsii lechbnykh ortopedicheskikh izdelii iz polimernykh materialov

In traumatological hospitals the medical orthopedic articles made of polymer materials are contaminated by different microorganisms including pathogenic staphylococci, therefore they can serve as a factor of transmission of hospital-associated staphylococcal infections. Polymer materials used for medical orthopedic articles are not bactericidal. Mechanical cleaning with detergents does not provide sufficient elimination of microorganisms from orthopedic articles. This can be obtained by means of the treatment (immersion, wiping) with solutions of bactericidal preparations of various chemical orogin (chloramine, lithium hypochloride, chlorine, sulphochlorantine, hydrogen peroxide, peracetic acid, nitran). Medical orthopedic articles must be decontaminated before use. In the hospitals, disinfection of orthopedic articles should be performed at least once a day. Immersion of the articles made of porous materials into solutions of disinfectans with surface-active additives or into solutions of surface-active bactericides is a simple, readily available and effective method of treatment. Drawback of this method is that disinfectant solution partly remains in the pores and can be eliminated only by means of drying of the article in thermostate. Orthopedic articles of polyurethane foam can be decontaminated only by use of solutions of hydrogen peroxide and nirtan out of all the tested disinfectants. Medical orthopedic articles made of polymer materials have endured repeated treatment with disinfectant solutions without any change of their physical and mechanical properties. The usability of these articles did not deteriorate.