ABSTRACT
Yersinia enterocolitica serotype O:3 and O:8 urease-negative mutants unable to express the 19-kDa beta subunit of urease were constructed and tested for virulence and arthritogenicity. Our results indicate that urease is needed for full virulence in oral infections and that it is not an arthritogenic factor in the rat model.
Subject(s)
Arthritis, Infectious/etiology , Urease/physiology , Yersinia enterocolitica/pathogenicity , Animals , Female , Male , Mice , Mice, Inbred DBA , Rats , Rats, Inbred Lew , Serotyping , Urease/deficiency , Urease/genetics , VirulenceABSTRACT
Patterns of long-chain faecal fatty acids were studied by gas-liquid chromatography in 55 newborn infants in a neonatal intensive care unit. Decreased fractions of fatty acid C16:1 and increased fractions of C16:0 and C17:0 were associated with the occurrence of abdominal distension. Decreased fractions of C16:1 and C18:2 were associated with diarrhoea. Flatulence was found in infants who had relatively smaller amounts of fatty acids C17:0D and C15:0 in their faecal samples. The differences in the patterns of faecal fatty acids are due to differences in bacterial flora. The results support the hypothesis that the initial intestinal colonization plays a role in the later gastrointestinal signs of newborn infants.
Subject(s)
Fatty Acids/analysis , Feces/chemistry , Gastrointestinal Diseases/etiology , Diarrhea/etiology , Humans , Infant , Infant, Newborn , Intestines/microbiologyABSTRACT
In 1989, we observed in our neonatal intensive care unit (NICU), an increased number of infants with gastrointestinal signs, including five cases of necrotizing enterocolitis. Clostridium perfringens was found in 26% of newborns (n = 168) and was associated significantly with the occurrence of flatulence, distended abdomen, foul-smelling stools, diarrhea and blood in stool (all p < 0.001). C. difficile was found in 17% of the newborns (n = 72). Cesarean section, low gestational age and low birth weight were significantly associated with C. perfringens in stools (all p < 0.001). Treatment with antibiotics was not associated with occurrence of C. perfringens. However, in infants with C. perfringens, intrapartum antibiotics were associated with increased appearance of abdominal distension (p < 0.05). Thus the antibiotics, which disturb primary colonization, may also favor the pathogenic role of opportunistic gut bacteria, such as C. perfringens.
Subject(s)
Anti-Bacterial Agents/adverse effects , Clostridium perfringens/isolation & purification , Enterocolitis, Pseudomembranous/microbiology , Feces/microbiology , Clostridium Infections/etiology , Digestive System/microbiology , Female , Humans , Infant , Infant, Newborn , Intensive Care Units, Neonatal , Labor, Obstetric , Maternal-Fetal Exchange , PregnancyABSTRACT
We studied Malassezia furfur colonization of neonates in the neonatal intensive care unit (NICU) and found that the rate was astonishingly high as compared to the previous studies. In very low birth weight (less than 1,000 g) infants we recorded a colonization rate of 80%, and 4% infants with a birth weight greater than 2,000 g. Under 10 day's hospitalization the rate was 11%, and it was 70% after 20 days spent in the unit. Among the infants with the birth weight less than 1,700 g, antibiotic therapy was recorded as a significant risk factor for colonization. In the infants with a greater birth weight, the colonization rate was independent from the risk factors studied. M. furfur colonization could not be linked with occurrence of any symptoms of signs recorded and colonization by M. furfur was so common in NICU that the predictive value of surveillance cultures is poor.
