Zentralblatt fur Bakteriologie, Parasitenkunde, Infektionskrankheiten und Hygiene. Erste Abteilung Originale. Reihe A: Medizinische Mikrobiologie und Parasitologie最新文献

Protein A (PA) could be extracted completely from Staphylococcus aureus by treatment with concentrated formic acid. This led to the development of a semi-quantitative determination of PA by hemagglutination (fig. 1). The treatment with formic acid yielded PA more effectively than the commonly used extraction by boiling (table 1). It could be conducted directly on a loopfull of staphylococci obtained from blood agar. It required no additional cultivation in a fluid medium. Most suitable for the hemagglutination was a commercial preparation of Rh-positive human erythrocytes, blood group O, loaded with Rh-antibodies from humans. This relatively stable preparation had also a higher susceptibility for PA in the slide-test and served for a better detection of PA-positive staphylococci (table 2).

The kinetics of the bactericidal activity of 80 vol% of fresh human serum against representative 'delayed serum-sensitive' (DSS) and 'promptly serum-sensitive' (PSS) strains of Serratia marcescens were further examined with regard to various chemical and absorption procedures known to affect various components of the alternative and classical pathways of human complement activation. Inulin treatment of fresh human serum failed to diminish serum bactericidal activity against DSS and PSS assay strains. Fresh human serum that had been depleted of properdin (factor P) through absorption with zymosan, was as active as control serum against DSS strains of S. marcescens; however, PSS strains were killed in a 'delayed' fashion. Human serum that had been heat-inactivated at 50 degrees C for minutes (depletion of factor B), no longer killed DSS strains, whereas PSS strains of S. marcescens and the PSS control strain Escherichia coli C were killed in a slightly delayed fashion. Hydrazine-hydrate treatment (inactivation of C3 of the complement system) and exposure of fresh human serum to dithiothreitol completely abolished serum bactericidal activity. Bentonite-absorbed fresh human serum no longer killed DSS strains of S. marcescens; some PSS strains of S. marcescens were killed in a delayed manner, whereas control strain E. coli C was as PSS as before. Addition of Seitz-filtered fresh human serum, that lacked beta-lysin and was deficient in lysozyme, to bentonite-absorbed human serum restored bactericidal activity against DSS and PSS strains of S. marcescens; addition to heat-inactivated or Seitz-filtered, heat-inactivated human serum failed to do so. Therefore, bentonite absorption removed to a heat-labile component from fresh human serum clearly different from beta-lysin and lysozyme. Furthermore, human serum beta-lysin and lysozyme were not required for serum-mediated killing of S. marcescens strains of either serum susceptibility category.

The development of acute bacillary dysentery was followed in 23 patients involved in two outbreaks and in three sporadic, mutually unrelated cases. Repeated cultivations performed at 2-day intervals for 10 days yielded 386 identifiable strains of "opportune intestinal flora". Escherichia coli colicinogenic activity is one of the significant factors of gastrointestinal tract protection. The period of shigella excretion is significantly reduced (p less than 0.02) if an appropriate colicinogenic E. coli strain is present. Analysis of the results suggested a working hypothesis of differentiated approach to bacillary dysentery treatment in outbreaks. In the absence of a suitable colicinogenic flora neomycin therapy should be administered since it does not damage the natural colonizing flora (bacteroids, bifidobacters, aerobic lactobacilli); in the presence of a suitable colicinogenic flora, no antibiotic should be used as this would abolish the coli-flora.

Thirteen R plasmids derived from strains of E Enterobacteriaceae isolated from clinical material have been characterized. They belonged to many incompatibility groups and differ widely respecting other phenotypic characteristics, even if they come from bacteria isolated from a small geographic area.

The New Zealand National Serum Bank is a collection of human sera consisting predominantly of specimens taken from healthy New Zealand blood donors. The studies presented here were designed to assess the antibody levels in two urban centres to Brucella abortus, Toxoplasma gondii and several Leptospiral serogroups including all those found in New Zealand. In none of the sera could complement fixing leptospiral antibodies be detected. There was evidence of low level immunity to both Toxoplasma gondii and Brucella abortus.

Sera collected from 18 pregnant buffaloes and Fresian cows during the last two weeks before parturition and from the newborn calves during the first two weeks after birth. All the samples together with the colostral whey of the first three days were examined for the presence of E. coli agglutinins using the tube agglutination and passive hemagglutination tests. The latter test was more sensitive and demonstrated higher titres in all cases, and consequently more O groups. Agglutinins to various E. coli O groups were detected in all samples. It is worthy to note that agglutinins to all E. coli O groups used as antigens were detected in 13 dam's sera, 17 colostrum and in one buffaloe calf. The titres were higher in colostrum than in dam's or calf's sera. The highest titre was 1:640. The O groups 101, 115, 117, and 26 were the most common among Fresian cows whereby the O groups 101 and 115 showed the highest titres. In buffaloes the O groups 101, 115, 8 and 26 were the most common with the O8 having the highest titre.

The importance of the role of toxoplasma oocysts in the mode of spread of the infection for men and animal has differently been estimated. In own earlier experiments, we found out that the transmission of the infection by means of oocysts from cat to cat is not the rule. In a similar experimental setup, we tested now whether rabbits can be infected by getting into contact with faeces of cats containing sporulated toxoplasma oocysts (see table 1). 8 toxoplasma-free rabbits and two toxoplasma-free cats as control were placed on infectious faeces of 10 cats (group 1-8). As further controls served four non-infected rabbits being kept in the same cage (group 11-12). Four of eight rabbits which had been placed on the infectious faeces and one control animal having had no intended contact with those faeces got infected. Our experiments show that the question whether domestic cats have any significance as source of infection with toxoplasms cannot generally be answered. It has to be differentiated each time which mammal gets into contact with oocysts.

Agglutinin-absorption and precipitin-absorption studies demonstrated that three strains of Treponema hyodysenteriae isolated from cases of swine dysentery were antigenically different from each other and also from a spirochete isolated from a clinically normal dog. Each of the strains of T. hyodysenteriae also possessed two common antigens.