Effect of climatic-weather conditions on the incidence of miscarriage

Two new methods for serological grouping of beta-hemolytic streptococci, the nitrous acid extraction procedure of El Kholy et al. and the slide agglutination method of Christensen et al., were compared with the Lancefield hot-hydrochloric acid extraction method in classifying 92 strains of groups A, B, C, and G. The nitrous acid extraction method was easily performed, specific, and sensitive when highly potent antisera were used. For the Christensen method these highly potent antisera had to be diluted to avoid cross-reactions between groups A and C and groups B and G, respectively. A few strains, most of them group B, could not be grouped by the latter method. Using these three grouping methods, two sets of commercial sera were compared with the more potent sera supplied by R. C. Lancefield. The low antibody content of these commercial sera, especially anti-group B and G sera, contributed to the inferior results obtained in some of the grouping reactions.     

Genetic variability among yellow fever virus 17D substrains

The complete nucleotide sequence of the genome from two yellow fever (YF) virus strains, 17DD and 17D-213 was determined. Comparison of these sequences with those of other YF viruses, including the parental virulent Asibi strain, allowed the identification of 48 nucleotide sequence differences which are 17D strain-specific and potentially related to viral attenuation. Another 43 nucleotide sequence differences were not common to all 17D substrains and are therefore substrain specific. Of the 21 changes between 17DD and Asibi 15 only five led to amino acid substitutions whereas 13 substrain differences common to all 17D-204 substrains produced six amino acid substitutions. Since the exact passage histories of these viruses is known it was possible to calculate, for each strain, the number of accumulated changes per passage. Based on these data the 17DD strain was the most genetically stable virus.     

Lipid metabolism in the far North aborigens residing in the Krasnoyarsk territory]

A study of the fat metabolism in the Extreme North aborigens, whose ration is made up chiefly of proteins and fats, demonstrated a decline of the most studied metabolic indices, as compared to those in inhabitants of the temperate geographical belt. Results of a fat load test speak in favour of the organism of the Transpolar aborigens adapting itself to the specific composition of the food ration in the course of ontogenetic development.