Sensitivity to chemotherapeutics of Yersinia enterocolitica strains.

290 Y. enterocolitica strains were tested as regards their sensitivity to 20 chemotherapeutics. All the strains were isolated from fecal specimens taken from human beings in Czechoslovakia. It should be noted that the strains presented homologous group as they belonged to 3 serological group according to Winblad or IA according to Knapp and Thal, they also belonged to biotype 4 according to Nilehn. It has been found that apart from their homogenicity, they showed quite different patterns of sensitivity to chemotherapeutics. Among them quite a great number of the strains were of high level of resistance to antibiotics. It was not possible to transfer their resistance to the sensitive E. coli K12 strain. All the strains proved to produce betalactamase.

Enteropathogenicity of Plesiomonas shigelloides and Aeromonas spp. in experimental mono- and coinfection with Cryptosporidium parvum in the intestine of neonatal BALB/c mice.

Enteropathogenicity of Plesiomonas shigelloides, Aeromonas hydrophila, A. caviae and A. sobria was studied both in monoinfections and in coinfections with coccidium Cryptosporidium parvum in neonatal BALB/c mice. In monoinfection experiments, neonatal BALB/c mice were orally infected with 7 x 10(7) or 7 x 10(8) CFU, respectively, of a strain of P. shigelloides or a strain of an Aeromonas spp. In coinfection experiments, the neonatal mice were, in addition to being orally infected with one of the four bacterial species, orally infected with an inoculum containing 10(5) oocysts of C. parvum. Results from monoinfections with P. shigelloides revealed long-term colonisation of the neonatal mouse intestine by this pathogen, along with associated pathological lesions. The lesions varied in severity from atrophy to necrosis of the mucosal inner surface of the ileum and colon, with predilection to the colon and brush border of colonic enterocytes. The effects of coinfection of P. shigelloides with C. parvum were characterised by bacteremia and heavy colonisation of the intestine by P. shigelloides. In addition, extensive necrotising inflammatory changes in the ileum and colon were accompanied by diarrhoea and deaths of coinfected mice. In contrast, the results from monoinfections of neonatal mice with Aeromonas spp. showed only a short-term colonisation of the intestine by the pathogen. However, when mice were coinfected with A. hydrophila and C. parvum, then the growth of the bacterial species was prolonged, and occurred in both the spleen and intestine. However, no substantial clinical or histopathological changes were observed in mice, whether monoinfected with Aeromonas spp. or coinfected with C. parvum. Our study suggests that experimental monoinfections of neonatal BALB/c mice with P. shigellodes, Aeromonas spp. and C. parvum, together with coinfections (each bacterial species with the protozoan C. parvum), may serve as a useful model to study the initial steps of gastrointestinal colonisation and diarrhoeal disease syndromes caused by enteropathogenic bacteria and protozoa, individually and in combination.

New O and H antigens of the international antigenic scheme for Plesiomonas shigelloides.

A revised update of the International antigenic scheme for Plesiomonas shigelloides is presented. Twenty-six new O (O77-O102) and 10 new H (H42-H50 and H1a1d) antigens have been described since 1994. The sources of antigens are mostly human clinical strains, isolates from warmblooded animals and a few environmental cultures.

A survey of colicin types and phage types of Shigella sonnei in Czechoslovakia 1976-1978.

Inthe years 1976-1978 3,552 strains of Shigella sonnei obtained from the whole Czechoslovak territory by the method of colicin typing and phage typing was examined. Each strain represented always one focus. 81.3% of the strains were colicinogenic. Twenty-one colicin types, 41 characteristic and 105 non-characteristic phage types participated in bacillary dysentery. Of the total number, 77.4% belonged to 9 phage types (2, 3, 6, 65, 67, 75, NC IV-VIII- and NC III-IV-VIII-), which are endemic in Czechoslovakia. Of the 2,889 colicinogenic strains, 85% belonged to 3 colicin types: 2 = Ia (31%), 6/11 = E1 (27%), 12 = E6 (27%). Some phage types produced predominantly colicin of a certain type.

[The importance of serotyping Plesiomonas shigelloides]. / Význam sérotypizace Plesiomonas shigelloides.

The author presents an account of serovars of 432 strains of Plesiomonas shigelloides from various countries and sources; in addition to strains from man and animals also environmental strains. The most frequent serovars are O17 with three H antigens (H2, H11, H34) except for immobile strains, also O32:H4 and non-motile strains, O2:H1a1c and O44:H8. The other serovars did not reach the number of 10 strains, some serovars were found only one strain of each. Serovar O18:H2 was isolated in the course of 30 years only from cats and lynx and once from a pond in the FRG. As regards the distribution of different serovars, e.g. O68:H2 was found only in one district, while strains of the serogroup O17 come from various countries in the world. Between findings of the same serovar sometimes a 20-30-year interval elapses.

[Biochemical identification of aeromonads]. / Biochemická identifikace aeromonád.

To assess the species of the genus Aeromonas in 178 strains isolated from human and animal materials and from the environment (water and hospital environment), examined along with 11 type strains of the best known species, a key was used the basis of which are in addition to biochemical tests defining the genus Aeromonas 12 tests: Voges-Proskauer, lysine decarboxylase, gas from glucose, haemolysis, gluconate oxidation, elastase, arabinose, mannose, saccharose, salicine, esculine hydrolysis, arbutine. Three tests--salicine, esculine hydrolysis, arbutine--differentiate A. hydrophila (2-3 positive) from A. sobria (0-1 positive).

[Biochemical indicators of Citrobacter sedlakii]. / Biochemické znaky Citrobacter sedlakii.

The authors describe eight strains identified biochemically as a new species of C. sedlakii in clinical material, surface water and the cutting surface of a melon. The majority of strains was isolated in the Czech and Slovak Republic.

New serovars of plesiomonas shigelloides--1996.

Eight new 0 (91-98) and H (46-49) antigens are described. Their reference strains come from Czech Republic, Cuba and USA. The majority of reference strains are of human origin. Some of the new antigens have been found in other strains coming mostly from water.

New serovars of Plesiomonas shigelloides--1992-1998.

Most of the 26 new O (O77-O102) and 10 new H (H42-H50) and H1a1d antigens were found in various P. shigelloides strains isolated from man and other mammals, birds, fish, and water and water insects, not only in the Czech Republic but also in 12 foreign countries.

New serovars of Plesiomonas shigelloides 1992.

Fourteen new O (O77-O9O) and 4 new H (H42-H45) antigens were described. Seven O and 2 new H antigens were revealed among strains not agglutinating with antisera against 76 O and 41 H officially recognized serovars. The most frequent was serovar O80:H38 which was isolated in 5 countries (Sweden, Czechoslovakia, Bulgaria, Yugoslavia and Canada) from human material and from sewage and surface water.

Plesiomonas shigelloides in water and fish.

Plesiomonas shigelloides strains isolated from aquariums, surface water and fish were serotyped using the international antigenic scheme and a provisional scheme designed for environmental strains, called the "Schubert" scheme. A remarkable variety of serovars represented in both schemes was found, namely in surface water samples and in fish.

Characterization of Plesiomonas shigelloides from diarrheic children.

Infrastructure of 29 P. shigelloides strains isolated as the only positive finding from children with diarrhea (biochemical properties, antigenic structure, antigenic relationship to shigellae, ATB susceptibility and plasmids) were described. A big variety of 22 serovars in a relatively small number of strains was found, inclusive four new 0 (093, 094, 095 and 096) and one new H (H46) antigen. Some strains belonged to the so-called "Schubert antigenic scheme" the serovars of which come of surface water of small ponds in Germany.

Identification of Plesiomonas spp.: serological and MALDI-TOF MS methods.

Biochemical and serological profiles of isolates of Plesiomonas shigelloides were assayed using standard procedures in isolates from various clinical samples. Seventy-four isolates, including P. shigelloides type strain, were further characterized by MALDI-TOF MS using 3-methoxy-4-hydroxycinnamic acid as matrix. Multiple ions in the 3- to 12-kDa mass range were found in the spectra of each strain, from which the "species-identifying" unique biomarker ions were identified. After creating the species-specific patterns, a spectral database was generated for reliable, rapid, reproducible and accurate identification of Plesiomonas strains. The classical strain description (biochemical and serological) was thus complemented with the metabolic (proteomic) characterization.

Serotyping of Plesiomonas shigelloides strains with our own antigenic scheme. An attempted epidemiological study.

Thirty-four O and 19 H sera were used to test 169 strains of Plesiomonas shigelloides from several countries of three continents. The most frequent O serovar was O17 (O antigen identical with Shigella sonnei phase I) which occurred in the OH serovar combinations: O17:c, O17:d and O17:f. Some OH serovars were represented by a single strain; others, despite the small number of strains in hand, were evidently ubiquitous, having been isolated in mutually distant countries or at long time intervals. The source of our strains was most often human stools, diarrhoeal or collected at preventive examinations during epidemiological and ecological investigations, the droppings of animals (dogs, cats, pigs, sewer rats, water birds) and surface, sewer or aquarium water. The usefulness of serotyping in epidemiological investigation in the patients' environment was confirmed by a finding of two different serovars in one of our patients and her cat.