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B Rowe

Publications and source records attributed to B Rowe.

At least 109 records · Page 6Linked to original sources
PubMed1994

The use of gene probes, immunoassays and tissue culture for the detection of toxin in Vibrio cholerae non-O1.

Vibrio cholerae non-O1 strains were screened for the presence of cholera enterotoxin (CT) genes by means of digoxigenin-labelled polynucleotide CTA and CTB probes. In-vitro production of CT was investigated by the Y1 mouse adrenal cell assay, enzyme-linked immunosorbent assay (ELISA) and a commercial, reversed passive latex agglutination (RPLA) kit. Only two (0.25%) of 790 strains tested gave positive results with the CTA and CTB probes. The production of other bacterial cytotoxin(s) made it impossible to use the characteristic cell-rounding effect on Y1 cells for the detection of CT. CT production by the probe-positive strains was confirmed by the immunoassays. Two hundred and fifty-two of the 788 probe-negative strains were tested by both cell assay and immunoassays. Of these, 90% produced cytotoxin(s) in the cell assay. In addition, 37% gave positive results in CT-ELISA, but negative results with LT-ELISA and VET-RPLA. These results indicate the presumed presence of a toxin in V. cholerae non-O1 that is able to bind GM1 and react with antisera to CT, but which is not identical to CT.

Cell Line↗
PubMed1994

Plasmid profile typing provides a method for the differentiation of strains of Salmonella enteritidis phage type 4 isolated in Turkey.

Five phage types have been identified in 38 strains of Salmonella enteritidis isolated in Turkey in the 20-month period June 1992-January 1994. Strains belonging to phage type 4 predominated. Within phage type 4, plasmid profile typing has proved a useful method of strain discrimination and has confirmed the identity of a putative outbreak involving canteen workers in an industrial complex.

Bacteriophage T4↗
PubMed1994

The detection of Vero cytotoxin-producing Escherichia coli and Shigella dysenteriae type 1 in faecal specimens using polymerase chain reaction gene amplification.

Fifty consecutive faecal specimens received by the LEP were examined for the presence of Vero cytotoxin (VT) genes by polymerase chain reaction (PCR) gene amplification. Nineteen were positive by PCR and from 16 of these, VT positive Escherichia coli O157 were isolated. The remaining three samples were positive for VT genes by PCR but VTEC were not isolated. In a preliminary experiment, Shigella dysenteriae type 1 was isolated from a case of bloody diarrhoea following a positive amplification result.

Bacterial Toxins↗
PubMed1994

Hybridization of strains of Escherichia coli O157 with probes derived from the eaeA gene of enteropathogenic E. coli and the eaeA homolog from a Vero cytotoxin-producing strain of E. coli O157.

A total of 375 Escherichia coli O157 strains were tested by colony hybridization with the eae probe from the central portion of the eaeA gene of the classical enteropathogenic E. coli strain E2348/69. They were also tested with a probe, eaeO157, from the C-terminal end of the eae gene homolog from a Vero cytotoxin (VT)-producing strain of E. coli (VTEC) of serotype O157:H7. Both probes hybridized with all 246 O157:H7 or H- VTEC strains tested. The majority were from human infections, and the remainder were from cattle. A further 10 strains (H7 or H-) hybridized with both eae and eaeO157 sequences but not with VT probes. They resembled O157 VTEC and were probably naturally occurring derivatives that had lost VT genes. The remaining 119 strains of O157 were from human, animal, and food sources and belonged to 16 H types other than H7 or were H-. They were VT negative and differed in their properties from O157 VTEC: generally they fermented sorbitol in 1 day, produced beta-glucuronidase, and could not be phage typed by the scheme for O157 VTEC. The eae probe but not the eaeO157 sequence hybridized with 18 H8 or H39 strains, predominantly from human diarrhea. The remaining 101 VT-negative strains hybridized with neither probe. However, 16 strains of O157:H45 hybridized with a probe for diffusely adherent E. coli and attached to HEp-2 cells in a diffuse pattern. Serogroup O157 comprises strains with heterogeneous properties. The eaeO157 probe is a valuable addition to the VT probes used to differentiate O157 strains.

Animals↗
PubMed1993

Molecular subtyping within a single Salmonella typhimurium phage type, DT204c, with a PCR-generated probe for IS200.

We report primers and conditions for the generation by PCR of a probe for the DNA insertion element IS200. This probe was shown to be suitable for genotypic subtyping within a single phage type of Salmonella typhimurium. A collection of isolates of DT204c, a phage type implicated in the spread of multiple drug resistance in bovine animals and to man, was analyzed. Three IS200 profiles, corresponding to related chromosomal genotypes were characterized in DT204c. Molecular discrimination within a single phage type of S. typhimurium has general significance for genotypic typing, and for the definition of epidemiological clonality in Salmonella.

Base Sequence↗
PubMed1993

Expression of a new porin 'OmpE' by strains of Salmonella enteritidis.

Strains of Salmonella enteritidis expressed a novel porin with a subunit size of 35.5 kDa as shown by SDS-PAGE. This protein was expressed as a major outer membrane protein (MOMP) when grown on nutrient agar, McConkey agar or blood agar, or in Tris-succinate medium; but was only produced in trace amounts when strains were grown in nutrient broth. This OMP was produced by all strains of S. enteritidis examined, regardless of phage type, and expression was not related to the possession of a 38-MDa mouse-virulence plasmid or the ability of strains to make long-chain lipopolysaccharide. This new porin has been tentatively called OmpE.

Bacterial Outer Membrane Proteins↗
PubMed1993

Influence of feeding patterns on the artificial infection of laying hens with Salmonella enteritidis phage type 4.

Salmonella enteritidis phage type 4 was recovered significantly more frequently from the crops of birds which had been denied food for 24 hours than from birds allowed food ad libitum. There was, however, no difference in its isolation rate from tissues. Within one hour of infection, S enteritidis could be recovered from a variety of tissues, including the oviduct, of a small proportion of the infected birds.

Animals↗
PubMed1993

Ciprofloxacin versus ceftriaxone in the treatment of multiresistant typhoid fever.

A randomized trial comparing ceftriaxone (3 g given parenterally per day for 7 days) to ciprofloxacin (500 mg given orally twice a day for 7 days) in the treatment of blood culture positive typhoid fever was conducted. Twenty patients were openly randomized to receive ciprofloxacin and 22 to receive ceftriaxone. The outcome was classified as clinical failure in 6 patients (27%) in the ceftriaxone group, but in none in the ciprofloxacin group (p = 0.01). The mean duration of fever was four days in the ciprofloxacin group and about five days in the ceftriaxone group (p = 0.04). In the six patients in the ceftriaxone group who experienced failure, therapy was switched to ciprofloxacin and the patients became afebrile and asymptomatic within 48 hours. Patients with resistant strains of Salmonella typhi and patients with sensitive strains responded equally well to ciprofloxacin therapy. Analysis of a subset of 12 of the multiresistant strains revealed that resistance was encoded for by a transferable 180 kilobase plasmid. Ciprofloxacin represents a useful treatment option in areas where multiresistant strains are likely to be encountered.

Bacteriophage Typing↗
PubMed1993

Serological detection of verocytotoxin-producing Escherichia coli in patients with haemolytic uraemic syndrome in western Europe.

Sera from 45 patients from The Netherlands, Germany and Belgium who had a clinical diagnosis of haemolytic uraemic syndrome (HUS) were screened for antibodies to the lipopolysaccharide (LPS) of Escherichia coli producing Verocytotoxin (VTEC). Sera from 43 family contacts and 34 control patients were also examined. Using the techniques of EIA and immunoblotting, antibodies to the LPS of Escherichia coli O157 were found in 28 patients, and to the LPS of serogroups O115 and O145 in one patient and one family member respectively. The results of our study suggest that VTEC, and in particular Escherichia coli O157, might be a significant cause of HUS in Western Europe.

Antibodies, Bacterial↗
PubMed1993

Heterogeneity in expression of lipopolysaccharides by strains of Escherichia coli O157.

A total of 47 strains of Escherichia coli belonging to serogroup O157 were examined for the expression of long-chain lipopolysaccharide (LPS) by means of SDS-PAGE and silver staining. Strains belonged to 10 different flagellar (H) types or did not express flagella. Nine strains carried genes encoding Vero cytotoxin (VT). Strains of E. coli O157 expressed one of three LPS SDS-PAGE profiles designated A, B and C. Strains expressing profile A belonged to H-types 6 and 19, while those expressing LPS profile B belonged to H-types 2, 16, 20, 39, 42 and 45. Strains of E. coli expressing profile C belonged to H-types 7 and 8; strains producing VT expressed LPS profile C only, although not all strains with H-types 7 and 8 carried genes for VT. Regardless of H-type or the LPS profile expressed, serum antibodies produced by patients infected with strains of E. coli belonging to serogroup O157 would be detected by serological tests.

Antigens, Bacterial↗
PubMed1993

Properties of Vero cytotoxin-producing Escherichia coli isolated from human and non-human sources.

Vero cytotoxin-producing Escherichia coli (VTEC) are an important cause of disease in man and animals. In addition to the production of VT these strains may possess other properties that are required for full virulence. Examples of some recent molecular studies are reviewed. Use of oligonucleotide probes and the polymerase chain reaction provide methods for the identification and typing of different VT genes. Several VTEC have the ability to cause attaching and effacing lesions of the epithelial microvilli. Hybridization experiments with the eae probe (E. coli attaching and effacing) showed homology with VTEC of human origin of eight different O serogroups. Properties of VTEC from human infections have been compared to strains isolated from animals and foods.

Animals↗
PubMed1993

Iron restriction and the growth of Salmonella enteritidis.

Strains of Salmonella enteritidis were examined for their ability to remove ferric-ions from the iron chelating agents ovotransferrin, Desferal and EDDA. Growth of S. enteritidis phage type (PT) 4 (SE4) in trypticase soy broth containing ovotransferrin resulted in the expression of iron regulated outer membrane proteins (OMPs) of 74, 78 and 81 kDa, and unexpectedly the repression of expression of OMP C. The 38 MDa 'mouse virulence' plasmid was not required for the expression of the iron-regulated OMPs (IROMPs). SE4 was able to obtain iron bound to the iron chelator Desferal and EDDA without expressing a high-affinity iron uptake system. Strains of S. enteritidis belonging to PTs 7, 8, 13a, 23, 24 and 30 were also able to remove ferric ions from Desferal and EDDA without expressing a high-affinity iron uptake system. We conclude that strains of SE4 possess a high-affinity iron sequestering mechanism that can readily remove iron from ovotransferrin. It is likely that iron limitation, and not iron restriction, is responsible for the bacteriostatic properties of fresh egg whites.

Bacterial Outer Membrane Proteins↗