Biomedical subjects
Publications and source records attributed to N A Chistenkov.
As revealed, autolytic enzymatic system of hemolytic streptococcus, group A, expressed the maximal activity at the end of the exponential growth phase. Autolysis was accompanied by the release of N-acetylaminosugars and of free amino group. Optimal conditions for the lytic system function were chosen (composition, ionic strength, and buffer pH). The activating action of trypsin and chemotrypsin was demonstrated.
The passive hemagglutination test was used to determine antibodies to type antigens of the cell wall of streptococcus group A in 167 patients suffering from erysipelas, from whom 488 sera were obtained. Antibodies were revealed in 97.2% of the sera. There was a definite relationship between the clinical form of the disease and the level of antibodies: their lowest level and the absence of elevation in the course of the disease was noted in continuous-relapsing form of erysipelas; the appearance of antibodies to the new types of streptococcus was usually noted in late relapses of the disease, which permitted to attribute their occurrence to infection by the new types of the microbes. In individual cases the appearance of antibodies to the new types of streptococcus was observed at the early relapses of erysipelas; this could be explained by the exacerbation of a focus of chronic (endogenous) infection in the skin in the absence of reinfection. Continuous prophylactic administration of bicillin-5 produced no depressive effect on the antibody level in patients with relapsing erysipelas.
A method for disintegration of cells of group A streptococcus on the Edebeau extrusion press was developed. The level of disintegration was controlled by cell count in stained preparations, Coultier electronic counter and electron microscope. The streptococcus cell disintegration in the Edebeau extrusion press at a temperature of --40 degrees, a pressure of 3200 kg/cm2 and two cycles of the process was completed by 96-98%.