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B Rowe

Publications and source records attributed to B Rowe.

At least 199 records · Page 11Linked to original sources
PubMed1990

Characterization of a new putative colonization factor (CS17) from a human enterotoxigenic Escherichia coli of serotype O114:H21 which produces only heat-labile enterotoxin.

Enterotoxigenic Escherichia coli (ETEC) of serotype O114:H21, which produced only heat-labile enterotoxin (LT), gave mannose-resistant hemagglutination (MRHA) with bovine erythrocytes. One strain, E20738A, was shown to possess fimbriae of approximately 7.5 nm diameter. On SDS-PAGE two possible fimbrial polypeptides of molecular masses 17.5 and 15.5 kDa were seen; the 17.5-kDa band was the most prominent. Loss of LT and MRHA together from strain E20738A was associated with loss of a 100-MDa plasmid. An absorbed anti-strain E20738A serum reacted specifically with the 17.5- and 15.5-kDa polypeptides and bound to the intact fimbriae. This antiserum reacted positively in an ELISA with LT-positive E. coli strains of serogroups O8, O15, O48, O114, and O146. The antiserum did not react with ETEC carrying known colonization factors. The term coli-surface-associated antigen (CS) 17 has been used to describe the fimbriae.

Antigens, Bacterial↗
PubMed1990

Properties of strains of Escherichia coli O26:H11 in relation to their enteropathogenic or enterohemorrhagic classification.

Thirty-seven strains of Escherichia coli O26:H11 from infants and calves with diarrhea were examined for properties associated with enteropathogenic (EPEC) or enterohemorrhagic E. coli (EHEC). Strains were heterogeneous with respect to Vero cytotoxin (VT) production and hybridization with the EHEC plasmid-specific (CVD419) probe; 26 strains produced VT1; 1 produced VT2. Twenty-four of 27 VT+ strains and 5 of 10 VT- strains hybridized with the CVD419 probe and produced enterohemolysin; these properties are characteristic of EHEC. The strains did not hybridize with the EPEC adherence factor probe, a property characteristic of some EPEC. Nevertheless, 36 strains adhered to HEp-2 cells in a localized manner and were positive by the fluorescence actin staining (FAS) test that is considered to correlate with the ability to cause attaching and effacing lesions in vivo. EPEC and EHEC cause these lesions. Although the FAS test appeared to be the most general pathogenicity test for the O26:H11 strains, it could not be used to assign strains specifically to EPEC or EHEC groups.

Animals↗
PubMed1990

The fimbriae of human enterotoxigenic Escherichia coli strain 334 are related to CS5 fimbriae.

Escherichia coli strain 334 is a human enterotoxigenic strain of serotype O15:H11 which had previously been shown to produce 'attachment pili'. These fimbriae were compared with other colonization factors. From strain 334 a mannose-resistant haemagglutination positive colony 334A and a mannose-resistant haemagglutination negative variant 334C were isolated. By electron microscopy the fimbriae of strain 334A were shown to have a helical structure resembling coli-surface-associated antigen (CS5) fimbriae. An antiserum was raised to strain 334A and absorbed with a fimbriae-negative variant of that strain, 334C. By immuno-electron microscopy this antiserum was shown to coat fimbriae of strain 334A but not CS5 fimbriae produced by strain E17018A. Conversely, CS5 antiserum did not coat the fimbriae produced by strain 334A. No antigenic cross-reaction was detected between these intact fimbriae when anti-strain 334A serum and CS5 antiserum were used in immunodiffusion tests. By enzyme-linked immunosorbent assays (ELISAs) the fimbriae of strain 334A were shown to be antigenically unrelated to most other human ETEC adhesins, namely colonization factor antigens (CFA/I, CFA/III and CFA/IV), coli-surface-associated antigens (CS1, CS2, CS3, CS4, CS6 and CS17) and putative colonization factors (PCFO159:H4 and PCFO166). However, a heated suspension of strain 334A reacted weakly with CS5 antiserum in an ELISA. By SDS-PAGE the fimbriae of strain 334A were shown to consist of subunits of similar size to CS5 subunits, that is about 21.5 kDa. Western immunoblotting revealed that the subunits of 334A and CS5 fimbriae shared common epitopes.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterial Adhesion↗
PubMed1990

Attaching and effacing lesions in vivo and adhesion to tissue culture cells of Vero-cytotoxin-producing Escherichia coli belonging to serogroups O5 and O103.

Certain isolates of Escherichia coli from humans and animals with enteric disease attach to enterocytes and cause 'attaching and effacing' (AE) lesions. E. coli strain S22-1, serotype O103:H2, isolated from a child with diarrhoea, contained two plasmids; one of these (pDEP12) hybridized with the CVD419 DNA probe derived from a plasmid found in E. coli O157:H7 and associated with expression of fimbriae and ability to adhere to Intestine 407 cells. Strain S102-9, serotype O5:H-, isolated from a calf with dysentery, contained six plasmids, one of which also hybridized with the CVD419 probe. Loss of pDEP12 coincided with reduced adhesion to HEp-2 or Intestine 407 cells cultured in vitro; reintroduction of this plasmid restored adhesiveness. Loss of the plasmid in strain S102-9 that hybridized with the CVD419 probe did not cause a decrease in adhesion. Accumulations of actin were seen in vitro in the fluorescence actin staining (FAS) test of strains S22-1, S102-9 and their derivatives, irrespective of the plasmid content of these strains or the prevalence of attached bacteria. Strain S22-1 and its plasmidless derivative caused AE lesions of equal severity in experimentally infected gnotobiotic piglets; piglets inoculated with an isolate from a healthy human or pig did not develop these lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adhesins, Escherichia coli↗
PubMed1990

Examination of strains belonging to enteropathogenic Escherichia coli serogroups for genes encoding EPEC adherence factor and Vero cytotoxins.

Four hundred and forty-nine strains isolated from patients with diarrhoea and belonging to 13 enteropathogenic Escherichia coli (EPEC) O serogroups were tested with a DNA probe for the EPEC adherence factor (EAF). Positive results were obtained with only 36 strains; they belonged to 10 O serogroups and flagellar typing showed they were usually of the "classical" EPEC serotypes. Thirty-four of the 36 EAF-positive strains showed localised adhesion to HEp-2 cells. The two remaining strains, of serotypes O114:H2 and O127:H4, showed low level or no adhesion to HEp-2 cells. No colonies hybridising with the EAF probe were identified in cultures from 115 faecal specimens from healthy children. Sixteen of the 449 strains hybridised with one or both probes for the Vero cytotoxin genes VT1 and VT2; 15 of the 16 strains belonged to serogroups O26 and O128. None of the strains hybridised with both the EAF and VT gene probes. These studies show that the great majority of strains belonging to EPEC O serogroups do not possess the EPEC adherence factor or carry VT genes.

Bacterial Adhesion↗
PubMed1990

The invasiveness of different strains of Salmonella enteritidis phage type 4 for young chickens.

Five strains of Salmonella enteritidis phage type 4 (PT4) isolated in 1978, 1984 and 1988 were examined for their ability to colonise the caecum and invade the liver of day-old chickens. All strains were capable of caecal colonisation and there were no differences in their colonisation ability in this respect. In contrast there was a gradation in the ability of strains to invade the liver, with strains isolated in 1988 proving the most invasive. Absence of a 38 megadalton (Md) plasmid, which has been shown to be involved in the virulence of S. enteritidis PT4 for BALBc mice, had little effect on the ability of strains of this phage type to colonise the caecum or invade the liver of day-old chickens. These results suggest that recent isolates of PT4 may have enhanced virulence for chickens which is not necessarily associated with the carriage of a 38 Md plasmid.

Animals↗
PubMed1990

Roles of different coli surface antigens of colonization factor antigen II in colonization by and protective immunogenicity of enterotoxigenic Escherichia coli in rabbits.

The roles of the subcomponents of colonization factor antigen II, the coli surface antigens CS1, CS2, and CS3, as colonization factors and protective antigens was studied in a nonligated rabbit intestine model (RITARD). Infection with enterotoxigenic Escherichia coli (ETEC) carrying CS3 alone or CS1 plus CS3 induced diarrhea in most (80%) of the rabbits, whereas nonenterotoxigenic strains expressing CS1 or CS2 rarely induced diarrhea. Strains carrying CS1, CS2, or CS3 alone were all shed in stools for a significantly longer period than normal fecal flora-type E. coli. Initial infection with ETEC positive for CS1 plus CS3 induced significant protection against disease caused by reinfection with a highly diarrheagenic dose of the homologous strain; rabbits previously infected with serotype-heterologous, nontoxigenic bacteria carrying CS1 only were also protected against this challenge, whereas no such protection was induced by serogroup-homologous E. coli carrying CS2 only. Animals previously infected with CS1-, CS3-, or CS1-plus-CS3-positive bacteria excreted the CS1-plus-CS3 challenge strain for a significantly shorter period than did "nonimmunized" rabbits, whereas initial infection with bacteria carrying CS2 only did not result in such reduced shedding. Monoclonal antibodies against CS1, CS2, or CS3 all protected against experimental infection with ETEC carrying the corresponding CS factor. These results suggest that all the subcomponents of colonization factor antigen II are colonization factors and may induce anticolonization immunity.

Animals↗
PubMed1990

Extended serogrouping scheme for motile, mesophilic Aeromonas species.

A total of 1,255 strains of motile, mesophilic Aeromonas species isolated from clinical and environmental specimens in the United Kingdom and 258 strains isolated in Australia, Brazil, Peru, and the United States were examined by using antisera for serogroups O1 to O44 (R. Sakazaki and T. Shimada, Jpn. J. Med. Sci. 37:247-255, 1984) and for unpublished serogroup O45 (R. Sakazaki). The typeability rate for strains isolated in the United Kingdom was 35%; the strains isolated in other countries had typeability rates of between 14 and 43%. A total of 52 provisional new serogroups were identified, and the strains with unidentified O groups were examined by using antisera for these provisional new serogroups. The typeability rate for strains isolated in the United Kingdom was increased to 66% (70% of smooth strains). The typeability rates were 76% for A. hydrophila and 63% for both A. caviae and A. sobria. The 52 antisera for the provisional new serogroups increased the typeability rate for strains isolated outside the United Kingdom to between 43 and 68%. This extended serogrouping scheme would be of value in determining the importance of Aeromonas strains as human intestinal pathogens and in investigating the pathogenic mechanisms that may be involved in the production of diarrheal disease.

Aeromonas↗
PubMed1990

Haemolytic uraemic syndromes in the British Isles 1985-8: association with verocytotoxin producing Escherichia coli. Part 1: Clinical and epidemiological aspects.

A prospective study of the clinical and epidemiological features of the haemolytic uraemic syndromes was conducted over a three year period in the British Isles. Two hundred and ninety eight children were reported. In two thirds of cases stool samples were analysed for the presence of Verocytotoxin producing Escherichia coli (VTEC) and neutralisable Verocytotoxin. A total of 273 (95%) patients had a prodrome of diarrhoea. In these a seasonal variation in the incidence of haemolytic uraemic syndrome was demonstrated, the 1-2 year age range was most often affected, and the peripheral blood neutrophil count correlated positively with an adverse outcome. Patients presenting without diarrhoea showed none of these associations and had a significantly greater morbidity and mortality. Evidence for VTEC infection was found in 58 (33%) of 178 diarrhoea associated cases whose stools were analysed, although VTEC were identified in five of eight (62%) patients whose stools were collected within three days of the onset of diarrhoea. Most isolates produced VT2 either alone, or together with VT1. There was no evidence of VTEC infection in patients without prodromal diarrhoea.

Bacterial Toxins↗
PubMed1990

Haemolytic uraemic syndromes in the British Isles, 1985-8: association with verocytotoxin producing Escherichia coli. Part 2: Microbiological aspects.

In a three year study of children under 16 years with haemolytic uraemic syndrome faecal samples were examined for the presence of Verocytotoxin producing Escherichia coli (VTEC) using DNA probes and for free neutralisable Verocytotoxin in a Vero cell assay with specific antisera. There was evidence of VTEC infection in 58 of 185 (31%) samples. A total of 53 VTEC was identified from patients with haemolytic uraemic syndrome. Thirty eight VTEC belonged to serotype O157:H7 or O157:H-, 34 produced VT2 only, and four strains produced both VT1 and VT2. The remaining 15 VTEC belonged to nine different O serogroups; three strains produced VT1, 10 produced VT2, and two were positive for VT1 and VT2. Three control groups of patients without haemolytic uraemic syndrome were also examined. There was evidence of VTEC infection in 8%, 6%, and 4% of specimens from individuals with bloody diarrhoea, those with diarrhoea only, and healthy controls respectively. VTEC from the bloody diarrhoeal and diarrhoeal controls were O157:H7 but those from the healty controls could not be O serogrouped. This study confirms the association of VTEC, and particularly strains of O157:H7, with haemolytic uraemic syndrome. Strains producing VT1, VT2, or both toxins were isolated, although over 94% of VTEC produced VT2 alone or together with VT1.

Adolescent↗
PubMed1990

Simple technique for detecting K1 antigen of Escherichia coli.

The K1 antigen is a poor immunogen, its detection by serological means is difficult, and previously described methods using K1 specific bacteriophages require standardised suspensions of five different bacteriophages. A simple technique was developed which uses an unstandardised suspension of a single K1 specific bacteriophage applied with a 1 mm wire loop to bacteria streaked on to cystine lactose electrolyte deficient (CLED) medium. The technique correctly identified all 99 known K1 strains tested, including 14 strains negative with the serological method. Among 71 clinical isolates from urinary tract infections, the single bacteriophage method distinguished 30 K1 strains from 41 strains without this antigen. Suspensions of the bacteriophage were shown to remain fully active for at least two years when stored at 4 degrees C. It is concluded that this technique required so little in materials, time, or equipment that it could be routinely used in most laboratories.

Antigens, Bacterial↗
PubMed1990

Multiple drug resistance in salmonellae in England and Wales: a comparison between 1981 and 1988.

Each year from 1981 through to 1988 the most common serotypes isolated from man in England and Wales and identified at the Division of Enteric Pathogens were S typhimurium, S enteritidis, and S virchow. In 1981 these three serotypes accounted for 45%, 12%, and 7% of isolations. The remaining 35% comprised strains belonging to a further 188 different serotypes, none of which accounted for more than 1% of the total. In 1988 S typhimurium accounted for 24% of isolations, S enteritidis 57%, and S virchow 4%. The remaining 15% comprised strains of a further 184 serotypes. The resistances to the common antimicrobial drugs in non-typhoidal salmonellas isolated in England and Wales in 1981 and 1988 were reported with particular reference to resistance to four or more antimicrobial drugs (multiple resistance). For S typhimurium the overall percentage of resistant strains varied little, but multiple resistance more than doubled from 5% to 12%; in S enteritidis the incidence remained the same. In S virchow the percentages of strains resistant to all the antimicrobial drugs and in particular, to chloramphenicol, streptomycin, trimethoprim and furazolidone, rose from 0.2% to 10.4%. Salmonella enteritis in man is usually a self limiting disease and antimicrobial treatment is seldom required; but should spread beyond the intestine occur, effective antimicrobial treatment is essential. Under these circumstances a knowledge of the likelihood of resistances to commonly available drugs could be of considerable value to the clinician.

Anti-Bacterial Agents↗
PubMed1989

The outer membrane protein of enteropathogenic Escherichia coli, described as the 'localised adherence factor', is OmpF and probably not involved in adhesion to HEp-2 cells.

Strains of enteropathogenic Escherichia coli (EPEC) were examined for a factor, described as an outer membrane protein (OMP) of 32 kilodaltons (kDa) and reported to be involved in the adhesion of EPEC to HeLa cells. A comparable OMP of 35 kDa was detected in strains of EPEC, although expression of this protein was not related to the ability of strains to adhere to HEp-2 cells. The 35 kDa OMP was found to be heat-modifiable and peptidoglycan associated, and considered to be the porin protein OmpF.

Bacterial Adhesion↗
PubMed1989

Antigenic homology within human enterotoxigenic Escherichia coli fimbrial colonization factor antigens: CFA/I, coli-surface-associated antigens (CS)1, CS2, CS4 and CS17.

Immunoglobulins, prepared from polyclonal rabbit antisera raised against Escherichia coli fimbrial antigens, colonization factor antigen (CFA)/I, and coli-surface-associated antigens (CS)1, CS2 and CS4, were used to assess antigenic cross-reactions between these four fimbrial types by Western immunoblotting. Antibodies in a serum, prepared against CS4, cross-reacted strongly with the fimbrial subunits of CFA/I, CS1 and CS2. Antibodies in sera prepared against CFA/I and CS1 gave weak reactions with CS1 or CFA/I respectively and also with CS2 and CS4, while the antiserum prepared against CS2 did not react. CS4 antiserum also reacted with the CS17 fimbrial subunit, but not with the subunits of fimbrial antigens: CFA/III, CS5, putative colonization factor (PCF) 0159:H4 or PCF0166.

Antibodies, Bacterial↗
PubMed1989

Case-control study of infections with Salmonella enteritidis phage type 4 in England.

OBJECTIVE: To determine the source of indigenous sporadic infection with Salmonella enteritidis phage type 4. DESIGN: Case-control study of primary sporadic cases identified by the Public Health Laboratory Service between 1 August and 30 September 1988. SETTING: PHLS Communicable Disease Surveillance Centre, Division of Enteric Pathogens, 11 PHLS laboratories, and 42 local authority environmental health departments in England. SUBJECTS: 232 Patients (cases) with confirmed primary sporadic infection, for 160 of whom (88 female) (median age 30 years, age range 4 months to 85 years) data were obtained by questionnaire about consumption of fresh eggs, egg products, precooked chicken, and minced meat in the three days and one week before onset of the symptoms. Up to three controls, matched for neighbourhood, age, and sex (if aged greater than 11 years), were asked the same questions for the same calendar period. MAIN OUTCOME MEASURE: Association of primary sporadic infection with consumption of suspected food items. RESULTS: Illness due to S enteritidis phage type 4 was significantly associated with consumption of raw shell egg products (homemade mayonnaise, ice cream, and milk drinks containing eggs) (matched p = 0.02) and shop bought sandwiches containing mayonnaise (matched p = 0.00004) or eggs (matched p = 0.02). Illness was also significantly associated with eating lightly cooked eggs (unmatched p = 0.02), but not soft boiled eggs, and precooked hot chicken (matched p = 0.006). Reported consumption of eggs was not appreciably different between cases and controls before or after the median date of interview. CONCLUSIONS: Fresh shell eggs, egg products, and precooked hot chicken are vehicles of S enteritidis phage type 4 infection in indigenous sporadic cases. Public health education and reduction in contamination of eggs and infection of poultry with S enteritidis are needed to reduce the incidence of human infection.

Adolescent↗