Pyocin typing of Pseudomonas aeruginosa isolates from children with cystic fibrosis.

Pyocin typing and serotyping of 433 strains of Pseudomonas aeruginosa from children with cystic fibrosis (CF) showed that pyocin type 9 was predominant, particularly in association with polyagglutinating serotype. The common pyocin groups, 1, 5 and 10, made up only 20% of these isolates in contrast to reported rates of up to 89% in other studies using non-CF strains. No strains of pyocin type 3 were found.

Longitudinal studies of virulence factors of Pseudomonas aeruginosa in cystic fibrosis.

Among 111 strains of Pseudomonas aeruginosa from 49 children with cystic fibrosis, duration of colonization correlated with bacterial phenotype. We confirmed that P. aeruginosa from chronically colonized patients tended to be less motile, produce lower levels of protease and elastase, to be more sensitive to normal serum and to be polyagglutinating or untypable with standard antisera.

Influence of soluble haemagglutinins on adherence of Helicobacter pylori to HEp-2 cells.

In a study of six laboratory strains of Helicobacter pylori, two different modes of bacterial adherence to HEp-2 cells were found. Electronmicroscopy revealed that strains known to possess soluble haemagglutinin adhered intimately to the cell surfaces, with cupping of the plasma membrane and coalescence of glycocalyces at sites of attachment. Strains of H.

Sorbose fermentation in relation to acquisition and maintenance of enterotoxin plasmids in Escherichia coli.

Previous studies have shown that the majority of enterotoxigenic Escherichia coli (ETEC) strains isolated from humans failed to ferment sorbose. In an attempt to demonstrate if this phenomenon was due to enterotoxin (Ent) plasmid instability in sorbose fermenting strains, recipient E. coli strains were used in conjugation experiments with three donor Ent plasmids.

Cytotoxic effects of children's faeces: relation to diarrhoea due to Clostridium difficile and other enteric pathogens.

Cytotoxicity of faecal extracts was demonstrated in 47 of 88 children (54%) referred for microbiological investigation of stools. Cytotoxic Clostridium difficile and vertotoxigenic Escherichia coli (VTEC) were the pathogens identified most commonly but cytotoxicity was also found in association with Campylobacter jejuni, Salmonella spp, Shigella sonnei, Giardia lamblia, rotavirus, adenovirus and poliovirus type 1 which had been acquired by oral immunization. In two patients, one of whom had cystic fibrosis, cytotoxicity of faecal extracts was associated with isolation of Pseudomonas aeruginosa.

Soluble and cell-associated haemagglutinins of Helicobacter (Campylobacter) pylori.

Some plate-grown strains of Helicobacter (Campylobacter) pylori that were harvested into phosphate-buffered saline and left for 1 h released soluble haemagglutinins. These caused high-titre agglutination of human and guinea-pig erythrocytes, whereas chicken, sheep and bovine erythrocytes were agglutinated at various titres. Six of 10 strains which had been subcultured repeatedly did not possess soluble haemagglutinins.

Serotype and serum sensitivity of Pseudomonas aeruginosa from children with cystic fibrosis: longitudinal studies and typing with monoclonal antibodies.

Pseudomonas aeruginosa isolated from the respiratory tract of children with cystic fibrosis from Perth, Sydney or Brisbane, were serotyped with polyclonal antisera using the International Antigenic Serotyping System. Predominant strains were untypable among isolates from Brisbane (86% of 50 strains) and Sydney (60% of 50 strains) but 64% of the 408 isolates from Perth were polyagglutinating. The frequency distributions of typable strains showed differences from those reported in clinics in the northern hemisphere, but it appears that these local differences do not affect the emergence of strains with defective lipopolysaccharide antigens.

HEp-2 cell adherence and Vero cell cytotoxin production by EPEC strains isolated from children with diarrhoea in New Zealand.

A total of 112 EPEC strains isolated from children with diarrhoea in New Zealand were examined for mannose-resistant HEp-2 cell adherence and production of exotoxins. Enterotoxin production was not detected in any of the strains examined. Verotoxin production was detected in 13 (11.

Cardiovascular Diseases and Alimentary Comparison Study: preliminary analysis of data from Western Australia.

Data from 49 men and 48 women included in the Cardiovascular Diseases and Alimentary Comparison (CARDIAC) Study in Perth, Western Australia, were analyzed. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were positively correlated (p less than 0.01) with urine sodium, creatine, taurine, histidine, and 3-methyl histidine but not with calcium, magnesium, or potassium.

An antibacterial and antiviral powdered soft-drink base.

Soft-drink powdered mixtures have been developed which are bactericidal against a range of enteric bacteria and Staphylococcus aureus and which kill some enteric viruses in vitro. These mixtures could be used to help reduce risks of water-borne diarrhoeal illnesses, and as the basis for oral rehydration solutions, which would resist bacterial contamination after their preparation, to treat patients with diarrhoeal dehydration.

Pyloric stenosis in Western Australia, 1971-84.

Analyses of hospital records and census data for 1971-84 showed no significant increase in incidence of infantile hypertrophic pyloric stenosis in Western Australia. No link was found between breast feeding and incidence of disease. Low birth weight, short gestation pregnancies, and paternal family history of the disease were significant features.

Aeromonas cytotonic enterotoxin cross reactive with cholera toxin.

Isolation by affinity chromatography from crude culture filtrate of Aeromonas sobria of protein that cross reacted with cholera toxin (CT) revealed a toxin that produced fluid accumulation in rat ileal loops and in infant mice and caused rounding of Y1 adrenal cells. All these activities were neutralised by antiserum to CT. There was no haemolytic or cytotoxic activity associated with this CT-cross reactive cytotonic enterotoxin.

Purification of cytotoxic enterotoxin of Aeromonas sobria by use of monoclonal antibodies.

Cytotoxic enterotoxin of Aeromonas sobria was purified by affinity chromatography with monoclonal antibodies. The purified enterotoxin gave a single protein band in polyacrylamide gradient gel electrophoresis and its mol. wt estimated by this technique was 63,000; it had a pI of 6.

Biotyping as a method of screening for enterotoxigenic Escherichia coli.

A scheme of biotyping described originally for E. coli isolated from urine was used to investigate enterotoxigenic (ETEC) and non-enterotoxigenic (non-ETEC) fecal E. coli.

Comparison of direct plating with the use of enrichment culture for isolation of Aeromonas spp. from faeces.

Direct plating of faecal specimens on blood agar was compared with the use of enrichment culture for isolation of Aeromonas spp. from faeces during a large epidemiological study. Of enterotoxigenic strains isolated by direct plating, 89% were associated with acute diarrhoea and 7% with an episode of diarrhoea during the month before collection, but 79% of enterotoxigenic strains isolated only after enrichment were not associated with acute diarrhoea.

Haemagglutination patterns of Aeromonas spp. related to species and source of strains.

The study included 138 A. sobria and 182 A. hydrophila isolated in Perth from samples of diarrhoeal or non-diarrhoeal faeces or from domestic water.

Protection of rats against cholera toxin and cholera-like enterotoxins by immunization with enteric-coated cholera toxin.

Pure cholera toxin (CT) given as a booster in enteric-coated tablets to rats produced a humoral and intestinal immune response similar to the result of instilling the boosting dose of CT directly into the duodenum. This method protects the antigen against gastric acid and allows delivery of the immunogen to intestinal mucosa, an essential step in producing intestinal secretory IgA. Immunization gave protection against pure CT during intestinal perfusion but also significantly protected against the secretory effects of E.

Partial characterisation of a soluble haemagglutinin from human diarrhoeal isolates of Aeromonas.

A soluble haemagglutinin has been identified in cell-free culture supernates of human diarrhoeal isolates of Aeromonas sobria, A. hydrophila and A. caviae.

Invasiveness of Aeromonas spp. in relation to biotype, virulence factors, and clinical features.

Of 69 fecal isolates of Aeromonas spp., 18 had the ability to invade HEp-2 cells. Invasiveness correlated with biotype; of the 18 invasive strains, 16 were A.

Breast milk lactoferrin levels in relation to maternal nutritional status.

Lactoferrin was measured in breast milk from Aboriginal and non-Aboriginal Australian women using an enzyme immunoassay. There was no diurnal variation in lactoferrin concentration or change in concentration between the beginning and end of a feed. Lactoferrin levels were significantly higher in the first 15 days postpartum than in the period after the 15th day.