Zentralblatt fur Bakteriologie, Mikrobiologie und Hygiene. 1. Abt. Originale A, Medizinische Mikrobiologie, Infektionskrankheiten und Parasitologie = International journal of microbiology and hygiene. A, Medical microbiology, infectious...最新文献

Streptococcus faecium strain M 74 was evaluated as a prophylacticum for enterotoxigenic Escherichia coli (ETEC) diarrhoea with human isolates of E. coli with CFA/I and CFA/II surface fimbrial haemagglutinins (adhesins) in a rabbit model. Young rabbits (3 to 4 days old) were given S. faecium organisms (5 × 10⁹) 15 min before (group A), 6 h before (group B) and 12 h after (group C) challenge with ETEC organisms. Only 4 out of 26 rabbits in group A, 6 out of 21 in group B and 7 out of 23 in group C developed diarrhoea. In conclusion, this S. faecium strain M 74 seems efficiently to protect animals from ETEC diarrhoea when given as a prophylactic agent at a high dose. This animal model seems useful for comparative studies on new preventive methods for ETEC diarrhoea such as testing probiotics and antiadhesive drugs.

Der Streptococcus faecium Stamm M 74 wurde im Kaninchenmodell auf seine prophylaktische Aktivität gegen eine durch enterotoxigene Escherichia coli-Stämme hervorgerufene Diarrhöe überprüft. Zur Infektion dienten E. coli Stämme mit den Fimbrien-Hämagglutinen (Adhäsinen) CFA/I und CFA/II. Drei bis 4 Tage alte Kaninchen erhielten über eine Schlundsonde 5 × 10⁹S. faecium Keime 15 min. vor (Gruppe A), 6 Std. vor (Gruppe B) bzw. 12 Std. nach (Gruppe C) der oralen Infektion mit 10⁹ enterotoxigenen E. coli-Keimen (ETEC). Diese Keimzahl rief bei sämtlichen Kontrolltieren eine reproduzierbare Diarrhoe hervor. In Gruppe A zeigten nur 4 von 26 Kaninchen eine Diarrhoe; 6 von 21 in Gruppe B und 7 von 23 in Gruppe C. Die Behandlung mit S. faecium Stamm M 74 schützt demnach vor einer ETEC-bedingten Diarrhoe, wenn hohe Enterokokkendosen appliziert werden. Das Kaninchenmodell ist für vergleichende Untersuchungen über neue Präventivmethoden der ETEC-Diarrhoe (Probiotica und anti-adhäsive Substanzen) geeignet.

Factors such as strain, fasting period, sex and age of the animals, and challenge dose were examined for their effects on the development of infection with Treponema hyodysenteriae in mice. Among mice tested, Ta:CF#1 mice were the most susceptible to the infection. Ta:CF#1 mice developed gross cecal lesions by a single oral dose ranging 10²-10⁷ colony-forming units of T. hyodysenteriae without preinoculation fast. Oral challenge with 10⁷ colony-forming units of the treponeme resulted in the development of gross lesions in all the mice at day 10. The number of T. hyodysenteriae in the feces and cecum of the mice reached the highest level at day 7 and 10, respectively; the levels lasted until day 21, the termination of the experiment. Macroscopic, microscopic and scanning electron microscopic findings of the lesions were similar to those of swine dysentery. These studies indicate that the Ta:CF#1 mice may be used as an excellent in vivo model system for swine dysentery.

Die Faktoren Stress, Nahrungsentzug, Geschlecht und Alter der Versuchstiere sowie Infektionsdosis wurden auf ihren Einfluß auf die Entwicklung der Treponema hyodysenteriae-Infektion in der Maus untersucht.

Von den untersuchten Mäusen waren Ta:CF#1 gegenüber der Infektion am empfänglichsten. Bei Ta:CF#1-Mäusen entwickelten sich nach einer oralen Einzeldosis von 10²-10⁷ CFU T. hyodysenteriae ohne Nahrungsentzug vor der Infektion makroskopisch erkennbare Zökalläsionen. Eine orale Immunitätsprüfung mit 10⁷ CFU T. hyodysenteriae führt bei allen Mäusen zur Entwicklung makroskopisch erkennbarer Läsionen am 10. Tag. Die Anzahl von T. hyodysenteriae in Fäzes und Zökum der Mäuse war am 7. bzw. 10. Tag am höchsten. Die Spiegel persistieren bis zum 21. Tag, an dem der Versuch beendet wurde. Die makroskopischen, mikroskopischen und rasterelektronenmikroskopischen Befunde in den Läsionen ähnelten denen bei Schweineruhr. Die Untersuchungen zeigen an, daß sich Ta:CF#1-Mäuse sehr gut als in vivo-Modellsystem für die Schweineruhr verwenden lassen.

The benzethonium chloride resistance of 341 strains of Pseudomonas aeruginosa isolated from Jikei University Hospital was determined. The distribution pattern of the susceptibility to benzethonium chloride clearly revealed two peaks, and the resistance was differentiated by 1000 (μg/ml (0.1%) of benzethonium chloride. The frequency of resistance to benzethonium chloride was 51.6%. Furthermore, the frequencies of resistance to SM, TC, CP, KM, GM, PIP, Hg, Cd, As and chlorhexidine were 42.5, 15.8, 41.3, 29.6, 14.0, 8.2, 88.3, 97.9, 97.1, and 74.5%, respectively.

Seven strains of Rothia dentocariosa were degraded by acid methanolysis and the non-hydroxylated fatty acid methyl esters released were examined by thin-layer and gas chromatography. The fatty acid profiles were composed of iso-, anteiso- and straight chain saturated fatty acids with 12-methyltetradecanoic (anteiso-C₁₅), 14-methylpentadecanoic (iso-C₁₆), 14-methylhexadecanoic (anteiso-C₁₇) and hexadecanoic acid (C₁₆) as major components. A small scale integrated procedure was used for the sequential extraction of isoprenoid quinones and polar lipids. The latter were examined by two-dimensional thin-layer chromatography and all of the test strains contained diphosphatidylglycerol, phosphatidylglycerol and two uncharacterised glycolipids. In all cases the major isoprenoid quinones were unsaturated menaquinones with seven isoprene units. Analyses of the cell wall amino acid composition using gas chromatography showed that the strains contained 2.5 to 5 moles of alanine and 1 mole each of glutamic acid and lysine. The chemical data support the integrity of Rothia dentocariosa and can be used to separate it from all other actinomycetes especially those which contain lysine in the wall peptidoglycan.

Reactogenicity testing was performed accompanying vaccination with the experimental German Hepatitis B Vaccine. 509 individuals, among them 343 healthy adults and 166 hemodialysis patients, were vaccinated with three doses of vaccine.

The evaluation of questionnaires indicated that local and systemic adverse reactions were of low intensity and short duration. The rates of reactions were highest following the first and lowest after the third vaccination.

The vaccine did not induce immunopathological alterations. The vaccine was non-infectious and thus not the cause of hepatitis B infections nor of other viral or bacterial infections.

Unter Verwendung eines experimentellen, deutschen Hepatitis B Impfstoffes wurde an insgesamt 509 Impflingen, darunter 343 gesunde Personen und 166 Dialysepatienten, nach jeder der drei Impfungen eine Verträglichkeitsprüfung durchgeführt.

Die anhand von Fragebögen angegebenen lokalen und systemischen Nebenwirkungen waren von geringer Intensität und kurzer Dauer. Nach der ersten Impfung wurde signifikant häufiger über Nebenwirkungen geklagt als nach der zweiten und dritten Impfung.

Die Vakzine induzierte keine immunpathologischen Veränderungen. — Der Impfstoff zeigte keinerlei Anzeichen von Restinfektiosität und verursachte weder eine Hepatitis B noch andere virale oder bakterielle Erkrankungen.

An in vitro evaluation of 32 gentamicin-resistant, Gram-negative bacteria from hygiene-centres in Berne, Switzerland and Bratislava, Czechoslovakia, revealed that 24 strains produced gentamicin-modifying enzymes. Occurrence of acetyltransferases (AAC) was confirmed in 16 strains, adenylyltransferase (AAD) /2″/ was observed in 13 strains while 5 of the gentamicin-resistant strains produced both enzymes. All Czechoslovak strains were amikacin-susceptible, in amikacin-resistant Pseudomonas aeruginosa strains from Switzerland the presence of AAC/6′/ was found. In the majority of gentamicin-resistant, netilmicin-susceptible strains the occurrence of AAD/2″/ was observed. Gentamicin-resistance in the modifying enzymes producing strains was due either to production of an acetyltransferase or the adenylyltransferase except Swiss strains of Serratia marcescens where a simultaneous production of both types of the enzymes was noted. Twenty eight strains produced an enzyme modifying animoglycosides of any kind.

In a time period of 21 days an experimental gingivitis was induced in 8 volunteers. Four volunteers received a carbohydrate-reduced, the other 4 persons a carbohydrate-enriched diet. Clinical investigations on the development of plaque and gingivitis and bacteriological examinations of the supragingival microflora were performed simultaneously. The change in the composition of the supragingival plaque-microflora were nearly independent of the amount of food-carbohydrate. In the beginning of the experiment all volunteers had an almost pure streptococcal microflora but during the course of the experiment, the supragingival flora developed to a complex microflora with 50% anaerobes. The reduction of the number of streptococci was accompanied by an increase in the number of Gram-negative rods and actinomycetes. The development of gingivitis in persons with carbohydrate-enriched food was more rapid than in persons with carbohydrate-reduced food. It was striking that the occurence of clinical symptoms correlated with the increase of the number of Actinomyces viscosus in the plaque material.

VHS virus shedding after experimental waterborne infection of rainbow trout was quantified by measuring virus infectivity in blood, faeces, and urine of catheterised fish. Virus shedding by urine with relatively high yields of infectious virus could be demonstrated during acute VHS until death, but not by faeces.

Trout, which were vaccinated against VHS or had survived the disease but showed no detectable humoral antibodies, may excrete infectious virus via urine for more than 30 days and without any signs of VHS after a secondary challenge infection. These results reveal the development of a carrier status of rainbow trout after VHS exposure.

The influence of culture medium composition on hemolytic effects produced by Listeria innocua on sheep blood agar has been investigated. Neither α- nor β-hemolysis could be observed around L. innocua colonies grown on sheep erythrocyte agar lacking glucose. However, green zones of hemolytic phenomena were observed around colonies grown on such agar which contained 0,6 % (w/v) glucose. By using L. innocua cell suspensions and culture filtrates this glucose-associated hemolysis only occurred in media which were weakly buffered (1 m M Na-PBS). This hemolytic phenomenon was attributed to the resulting acidification of the culture medium caused by the metabolic breakdown of glucose by Listeria. The results of this study demonstrate the necessity of including adequate buffer conditions when assaying the hemolytic property of a Listeria strain. It was found that the addition of 20 mM Na-PBS to the assay medium was sufficient to eliminate artificial “acidic-hemolysis”. Moreover, the hemolysis observed with known hemolytic Listeria strains was unaffected by this buffering, as was in fact the case even when conditions of higher buffering capacity were employed. By testing in this manner, no evidence has been found which would suggest the existence of an hemolysin, either intra- or extracellular, produced by Listeria innocua.

An accurate method for the determination of hemolysis caused by strains of the genus Listeria is proposed. This method of assaying hemolysis in a liquid grown medium has proven effective in determining the hemolytic properties of strains which appeared negative or questionable on blood agar as well as strains which in virulence tests were negative. The ability to accurately assess the hemolytic properties of Listeria strains, is essential in determining the association of Listeria hemolysin with pathogenicity of this genus. Together with current investigations on the genetics of hemolysin production by Listeria the determination of hemolytic activities will eventually allow to understand better the pathogenic principle of hemolytic strains of Listeria monocytogenes.

Five of 16 strains of Plesiomonas shigelloides, freshly isolated from children with acute diarrhoea, exhibited invasiveness for HeLa cells comparable to that of Shigella sonnei. None of the five, however, gave a positive reaction in the Sereny test. Although three of the invasive strains shared antigens with Shigella, no correlation was observed between invasiveness and the possession of such antigens. Only one of the invasive strains produced a toxin detectable as causing rounding of HeLa cells, although others released a product which inhibited protein synthesis in HeLa cells but which failed to provoke any dramatic morphological change.

5 von 16 Stämmen von Plesiomonas shigelloides, die frisch von an akutem Durchfall erkrankten Kindern isoliert worden waren, zeigten bei HeLa-Zellen eine Invasivität, die der von Shigella sonnei vergleichbar war. Keiner dieser fünf Stämme war jedoch im Sereny-Test positiv. Obwohl drei der invasiven Stämme eine Antigengemeinschaft mit Shigella zeigten, konnte kein Korrelation zwischen der Invasivität und dem Besitz solcher Antigene beobachtet werden. Nur einer der invasiven Stämme bildete ein Toxin, das sich durch die Rundung von HeLa-Zellen feststellen ließ. Die anderen setzten ein Produkt frei, das die Proteinsynthese in HeLa-Zellen hemmte, aber keine dramatische morphologische Veränderung hervorrief.