Initial bacterial floras in the throat and nose were examined on newborns from healthy mothers and those from mothers receiving chemotherapeutics.
Staphylococci were the most predominant flora in the nose. Within 12 hr. after birth they already resided in the nose of a few newborns. Almost all newborns became to harbor staphylococci in the nose and throat 3 days after birth, although the number of the organisms in the throat was less than that in the nose. Administration of chemotherapeutics to the mothers retarded the establishment of staphylococci in the nose and throat of the newborns.
In the throat of the newborns, viridans streptococci were most predominant, and 24 hr after birth about 50% of newborns from mothers not receiving chemotherapy became to harbor a huge number of the organisms in the throat. From the nose of newborns, viridans streptococci were only sporadically isolated. Chemotherapy for the mothers suppressed the establishment of viridans streptococci in the throat of the newborns.
Enterobacteriaceae (mostly Escherichia coli) were isolated from the throat of about 50% of newborns 4 days after birth. Of interest was that chemotherapy of mothers promoted the establishment of Enterobacteriaceae in the throat of the newborns, in contrast to the inhibitory effect of such treatment on the establishment of staphylococci and viridans streptococci.
Frequency of isolation of Staphylococcus aureus was much greater in the newborns from mothers not receiving chemotherapy than in those from mothers receiving chemotherapy. Differences of the ability of mannitol-fermantation and coagulase-production, and of the spectrum of sensitivity to 21 different antimicrobial drugs were observed between the S. aureus isolates from the nose and those from the throat, suggesting that at the organisms might establish themselves independently in the nose and throat.

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In my previous paper, initial bacterial floras in the throat and nose of newborn infants were studied and several interesting findings were reported. To corroborate the findings in human newborns, the present study was performed using newborn mice.
Staphylococci were the most predominant flora in the throat of newborn mice. Within 12 hours after birth, staphylococci were isolated from their throat as frepuently as their mothers or adult mice, and were found in the throat more frepuently and abundantly than in the nose. This fact is different from the fact that human beings carry staphylococci predominantly in the nose. Furthermore, it was noticed that viridans streptococci and Neisseria, which are common constituents of bacterial flora in the throat of human beings, were rarely isolated from nose and throat of newborn mice. Thus viridans streptococci and Neisseria appeared not to be constituents flora in the throat and nose of mice.
Among gram-negative rods isolated from the throat and nose of newborn mice, Enterobacteriaceae were rather rare and microorganisms except for Enterobacteriaceae were predominant. Unfortunately as these gram-negative rods could not be classified, they might be included in the same species. The estsblishment of staphylococci and gram-negative rods in the throat and nose of newborn mice was inhibited by administration of antibiotics to their mothers. Almost all the strains of staphylococci isolated from newborn mice delivered from untreated mothers were sensitive to all the tested antibiotics except for sulfisoxazole, while about 30-40% of staphylococci from mice whose mothers were treated with chloramphenicol and leucomycin were resistant to thiamphenicol and maclolides.

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Rapid laboratory diagnostic procedures are important for prevention and treatment of rheumatic fever and acute glomerulonephritis.
Most strains of group A streptococci which accounted for the major share of streptococcal infection in man, produce predominantly deoxyribonuclease-B, and high levels of neutralizing antibody for this specific enzyme are commonly found in patients convalescing from an infection with these organisms.
But, little data are as yet available regarding the frequency of DNase production by different streptococcal strains.
The present paper reports on DNase production by beta hemolytic streptococci compared with serological groups and T-types of these strains.
Also we studied on antibody titers to DNase B, streptolysin 0 and Hemoprobe-SZ test in seven year old children.
312 strains of beta hemolytic streptococci isolated from clinical materials were studied for DNase activity. The isolated strains were available for serological grouping: group A (191 strains), groupB (59), group C (12), and group G (50). T-typing of group A strains were for T-1 (20 strains), T-2 (1), T-3 (4), T-4 (26), T-5 (1), T-6 (3), T-8 (1), T-9 (4), T-11 (7), T-12 (60), T-13 (2), T-18 (5), T-22 (3), T-23 (3), T-25 (2), T-28 (4), T-B3264 (9), T-Imp. 19 (1), and untypable strains (35).
A qualtative agar slant method was used to determine DNase activity. Each strain was band streaked on a DNase test medium agar slant (Eiken Co. Ltd. Japan). These agar slants were incubated at 37°C for 20 hours to 40 hours. The enzymatic activity was determined by colour changes from blue to pink, and was differenciated as strong reaction (+), weak reaction (±), and negative (-).
Anti-deoxyribonuclease-B (ADNase B) titers were determined by measuring enzyme inhibition method (Wampole Laboratories, USA). Anti-streptolysin O (ASO) titers were determined by the modified method of Rantz and Randall (Nissui Co. Ltd. Japan). Hemoprobe-SZ test was carried out by hemagglutination method with using 100 diluted serum (Wampole Laboratories, USA).
188 of 191 (98.4%) of group A streptococci had strong DNase activity, and three strains which had weak activity were all T type B3264. Thirty-four of 59 (57.6%) of group B streptococci had weak activity. Only one group B strain had strong activity, and other strains were negative. Almost all of group C strains had no activity during first 20 hr incubation, but only two strains had weak activity during 20 hr. Eleven of 50 (22%) of group G had weak activity and others were all negative in 20 hr incubation. Two strains of group G had strang activity during 40 hr incubation.
Distribution of antibody titers for ADNase-B, ASO and Hemoprobe-SZ test among healthy school children was discussed.

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