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

The phagocytosis of two type 12 Streptococcus pyogenes strains differing in M protein presence was investigated in vivo. The rate of phagocytosis and the streptococcal viability in phagocytic cells and outside of them was studied simultanously with estimation of enzymatic activity in phagocytic cells. It was observed that M positive strain was phagocytized at lower rate and also exhibited longer viability. Decrease of lactic dehydrogenase and ATP-ase activity in phagocytes of rabbits infected with M+ strain was also detected. These results suggest that M protein disturbs phagocytosis by inhibiting their main metabolic pathway of glycolysis.

Recent work has shown that strains classified as M. mycoides subsp. mycoides may be separated into 2 types according to their growth rate and their behaviour in certain biochemical tests. The large colony (LC) types, most of which are from goats, are pathogenic for sheep and goats but apparently not for cattle. The small colony (SC) types include the classical contagious bovine pleuropneumonia (CBPP) strains from cattle and four strains from goats. These SC types are potentially pathogenic for cattle, sheep and goats. Strains of M. mycoides subsp. mycoides from CBPP differ in their virulence in cattle. The degree of virulence is correlated with the quantity of galactan produced in cultures of the organism, suggesting an important role for galactan in pathogenicity. This is consistent with the production by galactan of physiological effects in calves and in the enhancement of infection in cattle given galactan at the same time as cultures of the organism. Contagious caprine pleuropneumonia (CCPP) can be produced experimentally in goats using cultures of M. mycoides subsp. capri. Whether the glucan produced in such cultures is a factor in pathogenicity of this organism has not been determined. Hydrogen peroxide demonstrated in tracheal organ cultures of M. mycoides subsp. capri may contribute to its pathogenicity.

Immunogenicity and property of antigens obtained from Trypanosoma gambiense-infected mouse blood (IMP) were examined. A strong vaccine effect against intravenous challenges with 3 x10(3) parasites given on study day 3, 5, or 14 (day 0 = immunization) was observed in mice immunized with a combination of IMP (2 mg protein/mouse) and Freund's complete adjuvant (FCA). But when the challenge was given on day 21 or 30, per cent survival in mice dropped to the 20- and 40-per cent level, respectively. Among fractioned components of IMP, IMP-1, IMP-2, and imp-3, by gel filtration with Sephadex G-200, all of the mice immunized with IMP-1 antigen alone or together with FCA and challenged on day 5 were able to conquer intraperitoneal challenges with 1 x10(2) parasites. Mice immunized with IMP-2 or IMP-3 died within 6 days after challenge. Moreover, protection efficacy shown by IMP-1p (144,000 xg sediment of IMP-1) antigen in mice was similar to that by IMP and IMP-1 antigens. IMP-3 yielded a single precipitin line against mouse anti-IMP serum by Ouchterlony double diffusion method but this response was eliminated when the antiserum was absorbed by IMP-1p. No precipitin line was identified between mouse anti-IMP serum and IMP-1 or IMP-2. From electron microscopic observations, elements of IMP-1 and IMP-1p are possibly corresponded to the fragments of filopodia of the parasites.

Two groups of the intestinal microflora, the lactobacilli and the coliforms, were examined in thymus-deficient (nude) mice during the development of an experimental infection with the intestinal flagellate Spironucleus (Hexamita) muris and during the treatment with dimetridazole. The observed significant decrease in the number of lactobacilli under infection was probably due to the fact that the protozoan parasite fed on the microbes. Dimetridazole (0.3% in drinking water) did not influence the quantity of the lactobacilli but, owing to its selective killing of anaerobes and the lack of their antagonistic activity, a 100- to 1000-fold rise in the number of coliform microbes was observed. No of the drugs tested (dimetridazole, ornidazole, metronidazole, tinidazole, carbimazole BP and chlormethoxy-acridilamino-diethylamino-propanol-dihydrochliorde) was fully successful in the treatment of experimental spironucleosis in mice (Kunstýr, 1978) and it is suggested that recent reports on the therapeutic success of tinidazole in human giardiasis be treated with caution.

The prevalence of hepatitis B virus infections was examined in four groups from Liberia using radioimmunoassays for HBsAg, anti-HBs and anti-HBc. At the age of 15-19 years 90% have been infected, at the age of 40 years 100%. In a rubber plantation 30% had HBsAg, in the remaining 3 groups only 13% were HBsAg-positive. In the first group onchocerciasis was also a more frequent finding. However the parasitic infection was not the cause of the HBs-antigenemia. The HBsAg-concentration is mostly lower in the positive Liberians than in German HBsAg-carriers. Apparently the HBV caused frequently latent infections with low production of viral antigens in Liberia.

IgG, IgA, and IgM concentrations were measured at 40 acute and 9 chronic patients continuously during complications induced by facultative pathogenic Gram-negative bacteria, primarily by Pseudomonas aeruginosa. On the basis of the results the sudden decrease of Ig concentrations at the onset of complications, during shock, and before death was, beside the consuming effect of antigen-antibody reactions, most probably a consequence of increased capillary permeability and haemodinamic disorders due to antigen-antibody reactions and the effect of endotoxin. It was conspicuous, that a correlation could be found between the concentration of IgM and the development or final outcome of the complications: IgM values in cases of lethal complications in the acute patients were essentially lower than in the other patients surviving severe complications, even at the early period of complications still without any clinical signs of the outcome.

Study of the sensitivity of 141 strains of anaerobic and microaerophilic bacteria to nalidixic acid shows that few bacteria are inhibited by low concentrations (Veillonella, Eikenella, most of the Clostridia). Nalidixic acid appears to be bactericidal with respect to Clostridium perfringens, and its point of attack in the DNA is probably different from that of metronidazole.

A strain of Salmonella isangi was isolated from HUMANA milk, used a baby food in Bulgarian hospitals. It harbours two stable plasmids, distinguishable by their molecular weight of 21 Mdal for the transfer factor (rRB 1) and 9,3 Mdal for R-factor rRB 2, confering resistance to ampicillin, cephalothin, streptomycin and sulfonamides. Both plasmids are maintained in different copy numbers per chromosome genome equivalent, 8 copies for rRB 1 and 158 copies for rRB 2, associated with an unusual high level of resistance to ampicillin (MIC 65 mg/ml).

In the period July 1976 to June 1977 a total of 1358 fecal specimens and 165 mesenteric lymphnodes of healthy slaughterhouse pigs were examined for Yersinia enterocolitica (Y.e.). The animals originated from 215 farms in 86 localities of Northern Bavaria. Y.e. was found in fecal specimens of 371 pigs (27.3%). A total of 408 strains was isolated including 35 double and one triple infections. Most cultures belonged to serogroups O:6...(186 strains), O:7...(78 strains), and O:5...(71 strains, Table 3). The serogroups O:3 and O:9 which in Europe are most frequently associated with human disease were isolated from 26 animals (1.9%). Lymphnodes were positive in two instances only (1.2%). Besides aerobic subculture on SS-agar after cold enrichment in phosphate buffered saline anaerobic incubation was performed simultaneously during the last 8 months of the study. This method rendered more than twice as many isolations due to an effective inhibition of environmental bacteria with oxidative metabolism (mainly Pseudomonas spp.; Tables 3 and 4). The incidence of asymptomatic infections was markedly related to season. The lowest incidence was observed during the summer months (August 1976:0%) but increased steadily to a maximum in April 1977 (71.2%; Table 4). With one exception the serogroups O:3 and O:9 were only isolated during October to December (Fig. 1). Despite the frequent occurrence of Y.e. in healthy pigs the significance of these animals for human yersiniosis remains to be clarified. Especially the frequency of disease in infants and young children would not suggest porc meat as an important vehicle of transmission. It is imaginable that the human pathogenic serogroups O:3 and O:9 might be simultaneously adapted to several hosts with independent cycles of infection. Future investigations will mainly have to consider the elucidation of the hitherto unknown mode of transmission of human yersiniosis.