[Choice of commercial elective nutrient media for the isolation of pathogenic vibrios of different species]

Commercial nutrient media and their modifications are assessed, including elective differentiation medium for V. cholerae developed at the Rostov Research Anti-Plague Institute for the isolation of pathogenic vibrios. V. cholerae cholerae P-1 (145), V. cholerae el tor M-878, V. cholerae non 01 P-9741, E. coli 18, P. vulgaris 19, and 48 strains of vibrios belonging to different species were used in the study. All the strains used were characterized as to their nutritive requirements. Alkaline agar manufactured by the I. I. Mechnikov Research Institute of Vaccines and Sera was found to be the optimal medium for the isolation of pathogenic vibrios, for it provided the growth of all the examined strains from the inoculation dose of 100 bacterial cells. Addition of potassium tellurite to this medium in a dose of 30 to 50 mg/ml improved its selective properties. Elective differential medium for V. cholerae, though somewhat inferior to alkaline agar in sensitivity, provided the growth of colonies of the overwhelming majority of the strains and inhibited the growth of associated bacteria. Hence, these two media are recommended as elective media for the diagnosis and selection of pathogenic vibrio. Endo and Ploskirev's media with alkaline agar in 1 to 1 ratio may be recommended as additional ones for the isolation of vibrios from patients and from environmental objects.

Ganglia formation of the peripheral nervous system

Embryologic studies have shown that the ganglions of the peripheral nervous system are formed by the neuroblasts from the central nervous system. The histotopography of the neurons and their segmental communications with the central nervous system are established experimentally (segmental section of the ventral roots and resection of the spinal nodes: 100 experiments). It is proved that the neurons, which communicate with the definite segment of the spinal cord, are diffusely distributed in the ganglion mass.

[Use of media with antibiotics for isolating resistant forms of the cholera vibrios]

Higher stability of resistance to tetracycline in the polyresistant strain of V. eltor under conditions of macroorganism as compared to nutrient media was found experimentally. To increase isolation of the resistant forms of the cholera vibrio it was recommended to use agar with tetracycline or other antibiotics depending on the particular case in addition to the routine media.