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B Rowe

Publications and source records attributed to B Rowe.

At least 181 records · Page 10Linked to original sources
PubMed1991

Identification of enteropathogenic Escherichia coli isolated in Britain as enteroaggregative or as members of a subclass of attaching-and-effacing E. coli not hybridising with the EPEC adherence-factor probe.

Strains of Escherichia coli from sporadic cases of diarrhoea and belonging to serotypes O44:H18, O55:H7, O111ab:H21, O111ab:H25 or O126:H27 were examined for virulence properties. With the exception of O111ab:H25 these are considered to be classical enteropathogenic E. coli (EPEC) serotypes. The strains had been isolated in Britain from the faeces of children less than 3 years old. Of the serotypes examined, 7 of 13 O44:H18 strains, all of 10 O111ab:H21 strains and 13 of 21 O126:H27 strains belonged to the enteroaggregative class of E. coli (EAggEC) that attached to HEp-2 cells in the characteristic aggregative pattern and hybridised with the EAggEC probe. They also caused mannose-resistant haemagglutination of rat erythrocytes, a property which may be a useful marker for their identification. Strains of O44:H18 with similar properties were also isolated from three small outbreaks in Britain, one of which involved elderly patients. EAggEC have not been considered previously as aetiological agents of diarrhoea in developed countries and have rarely been reported as belonging to EPEC serotypes. All 15 O55:H7 strains and seven of eight O111ab:H25 strains were also considered to be potentially diarrhoeagenic as they gave localised attachment (LA) to HEp-2 cells that resulted in a positive fluorescence actin-staining test. This test is considered to correlate with the attaching-and-effacing virulence mechanisms of EPEC in vivo.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Examination of retail chickens and sausages in Britain for vero cytotoxin-producing Escherichia coli.

Samples from chickens and pork sausages were examined for the presence of Vero cytotoxin-producing Escherichia coli by using DNA probes for the Vero cytotoxin genes. Hybridization was detected in 25% of the 184 sausage samples, but none of the chickens was positive. No E. coli O157:H7 strains were isolated, and serotyping showed that the Vero cytotoxin-producing E. coli strains belonged to eight different O serogroups and that six strains had an unidentifiable O antigen.

Animals↗
PubMed1991

Escherichia coli O128 strains from infants with diarrhea commonly show localized adhesion and positivity in the fluorescent-actin staining test but do not hybridize with an enteropathogenic E. coli adherence factor probe.

Twenty-nine strains of Escherichia coli O128 isolated from infants with diarrhea that did not produce heat-stable enterotoxin, heat-labile enterotoxins, or Vero cytotoxin showed localized attachment to HEp-2 cells (LA). Only four strains hybridized with the enteropathogenic E. coli adherence factor (EAF) probe. One of the 25 LA+ EAF- strains attached to 72% of cells, while a plasmid-negative variant attached to 0.5% of cells. LA+ EAF- and LA+ EAF+ strains gave a positive fluorescent-actin staining test that correlates with the ability to cause attaching and effacing lesions in the intestine. The use of the EAF probe alone to detect LA+ strains is inadequate for epidemiological studies.

Actins↗
PubMed1991

Changes in the postenteropathic form of the hemolytic uremic syndrome in children.

An analysis was made of clinical and laboratory findings in children with the diarrheal form of the hemolytic uremic syndrome (HUS) treated at The Children's Hospital, Birmingham between 1970 und 1987. From 1982 the rate of referral increased, the prodromal illness more often consisted of bloody diarrhea, and the mean age at presentation doubled from 2 to 4 years. For patients with a good outcome there was an excess of males in the period 1970-81, and females in the period 1982-87. Moreover, in the years 1982-87 the disorder was distinguished from that of the earlier time by a positive correlation between adverse outcome and both neutrophil leukocytosis and a higher hemoglobin concentration at presentation. Prognostic scores obtained by logistic regression analysis were specific for each period. From July 1983 stool samples were analyzed for verocytotoxin-producing Escherichia coli (VTEC) and neutralizable verotoxin. Positive results were obtained in 39% of cases. The nature of HUS has changed and the new form of the disorder is associated with VTEC infection.

Acute Disease↗
PubMed1991

Awake porcine model of intraperitoneal sepsis and altered oxygen utilization.

We have characterized an awake swine model of septic shock. Hemodynamic, serum chemistry, and oxygen metabolism parameters were compared between eight septic and five sham animals. Eight male Yucatan miniature swine, weighing 20-28 kg, were anesthetized and catheters were placed in the pulmonary artery, external jugular, and the carotid artery. On day 2, 1.1-4.0 x 10(10) cfu Escherichia coli/kg were administered via an intraperitoneal catheter. Hemodynamic parameters were monitored hourly for 6 hours in awake animals. The animals were then placed back into the animal holding facility for clinical observation until the 24 hour post infusion measurements were taken. Septic animals were initially hypodynamic, with a decrease in cardiac index (CI) from a baseline value of 152.8 +/- 24.8 to 87.9 +/- 17.8 ml/kg/min (P less than .05) and an increased systemic vascular resistance index (SVRI) from a control value of 48.1 +/- 9.5 to 65.0 +/- 16.7 dynes*sec*cm-5/kg. At 24 hours post infusion, the animals were hyperdynamic with the CI increased to 211.0 +/- 27.2 ml/kg/min (P less than .05) and a decreased SVRI to 30.64 +/- 3.9 dynes*sec*cm-5/kg (P less than .05). Oxygen utilization (VO2) increased during sepsis from 6.6 +/- 0.8 to 8.1 +/- 0.8 ml/kg/min at 6 hours (P less than .05) and remained elevated at 24 hours at 7.7 +/- 0.4 (P less than .05). Increased oxygen consumption was attained with an increase in oxygen extraction (O2 ext) from 0.34 +/- 0.03 to 0.56 +/- 0.07 (P less than .05) during the first 6 hours of sepsis. At 24 hours, increased oxygen utilization was maintained by high oxygen delivery state. Significant alterations in serum chemistries in conjunction with post mortem evidence of multiple organ system failure were observed. Mortality on or before 4 days post infusion was 50% and positive blood cultures were obtained in 38% of the animals studied. This awake swine model serves as an excellent model to study metabolic pathophysiology and the treatment of septic shock.

Animals↗
PubMed1990

Structural and regulatory genes for coli surface associated antigen 4 (CS4) are encoded by separate plasmids in enterotoxigenic Escherichia coli strains of serotype 0.25.H42.

Two enterotoxigenic Escherichia coli strains of serotype 0.25.H42 that produced coli surface associated antigens CS4 and CS6 hybridized with a probe containing the cfaD sequence that regulates expression of colonization factor antigen CFA/I. Transformation of a cloned cfaD gene into some derivatives of the strains that were negative for CS4 and CS6 resulted in expression of CS4 but not CS6. By hybridization the sequence that regulated CS4 production in the wild type 025 strains was located on a plasmid that also encoded the CS6 antigen. The structural genes for the CS4 antigen were on a separate plasmid. The 025 strains carried a third plasmid encoding enterotoxin production which was therefore unlinked to regulation sequences or genes encoding CS antigens.

Antigens, Bacterial↗
PubMed1990

The expression of blood group P1 in post-enteropathic haemolytic uraemic syndrome.

Blood group P1 expression was scored by direct agglutination in 32 patients who had previously developed post-enteropathic haemolytic uraemic syndrome (HUS). Sixty-six children of similar ages undergoing venepuncture for other renal disorders acted as controls. The expression of P1 in controls was that expected from the normal caucasian population, 23% being negative. By contrast, there was an excess of HUS patients with weak or absent expression of P1 (chi 2 for linear trend 5.45, P less than 0.02), and this was particularly evident in those with a poor outcome. Verotoxin (VT), which is associated with HUS, requires the terminal disaccharide of the P1 antigen to bind to cells, and after internalization disrupts the transcription of ribonucleic acid. Mature erythrocytes do not synthesize protein and may be toxin resistant. We postulate that strong expression of P1 antigen may promote the binding of VT to red cells and thus reduce the dose to vulnerable nucleated endothelial cells. P1 positivity may be protective, and P1 negativity a risk factor in HUS.

Adolescent↗
PubMed1990

Plasmid-encoded production of coli surface-associated antigen 1 (CS1) in a strain of Escherichia coli serotype O139.H28.

Production of coli surface-associated antigen 1 (CS1) by Escherichia coli strain E24377 of serotype O139.H28 was controlled by a plasmid that also encoded heat stable and heat labile enterotoxins and CS3. The presence of a regulatory sequence was detected on this plasmid by hybridization with the cfaD gene that regulates expression of colonization factor antigen I fimbriae and is at least 96% homologous with the rns sequence controlling production of CS1 or CS2 fimbriae by strains of serotype O6.H16 of appropriate biotype. A separate plasmid, pDEP20, carrying the structural genes for CS1 synthesis was identified and transformed into E. coli strain HB101 or a derivative of strain E24377 without large plasmids. Transformants carrying pDEP20 did not produce CS1 fimbrial antigen, but antigen expression was obtained when a cloned cfaD gene or a wild-type plasmid carrying the rns sequence was introduced. Transposon mutagenesis with Tn1000 identified a 3.7 kbp region of pDEP20 essential for production of CS1 fimbriae. Genes encoding production of CS1 fimbriae were cloned on a 9.9 kbp BamHI fragment and were expressed in the presence of the cfaD sequence. A strain producing both CS1 and CS2 antigens was constructed by introduction of the cloned cfaD gene into a strain of serotype O6.H16 biotype C carrying plasmid pDEP20.

Antigens, Bacterial↗
PubMed1990

International increase in Salmonella enteritidis: a new pandemic?

Over the past 5 years Salmonella enteritidis infections in humans have increased on both sides of the Atlantic ocean. The WHO salmonella surveillance data for 1979-87 were reviewed and show that S. enteritidis appears to be increasing on at least the continents of North America, South America, and Europe, and may include Africa. S. enteritidis isolates increased in 24 (69%) of 35 countries between 1979 and 1987. In 1979, only 2 (10%) of 21 countries with reported data reported S. enteritidis as their most common salmonella serotype; in 1987, 9 (43%) of 21 countries reported S. enteritidis as their most common serotype; 8 (89%) of 9 were European countries. Although the reason for the global increase is not yet clear, investigations in individual countries suggest it is related to consumption of eggs and poultry which harbour the organism.

Animals↗
PubMed1990

The epidemiology of Salmonella infection of calves: the role of dealers.

Salmonellas were detected in the environment of 10 of the 12 calf dealers' premises studied. The cleaning and disinfection routines were often ineffective and salmonellas were isolated from 7.6% and 5.3% of the wall and floor samples before disinfection and 6.8% and 7.6% afterwards. Eight different salmonella serotypes were detected, of which the commonest were Salmonella typhimurium, predominantly phage type DT204C, and S. dublin. Plasmid profiles were used to fingerprint S. typhimurium DT204C and the results indicated that with the exception of one of the premises, prolonged salmonella-persistence in the environment was not occurring. Three separate epidemics of salmonellosis in calves were studied by use of plasmid profile analysis. The results illustrated the role of delers, and their subcontractors, in the dissemination of salmonellas. The study concludes with suggestions for methods to reduce the spread of salmonellas in the calf marketing chain.

Animals↗
PubMed1990

Serological response of chickens to Salmonella enteritidis infection.

Fifty-eight sera, from 29 chickens originating from two layer flocks known to be naturally infected with Salmonella enteritidis phage type (PT) 4, were examined for antibodies to S. enteritidis. Using the techniques of immunoblotting and ELISA, antibodies to the lipopolysaccharide (LPS) of S. enteritidis were detected in 43 of 58 sera. Antibodies were of the IgG class and bound to the S. enteritidis LPS antigen O = 12. Bacterial agglutination reactions using whole-cell preparations of S. enteritidis and S. pullorum, correlated with anti-LPS antibody reactions as detected by immunoblotting and ELISA. A rapid means of screening chicken sera for antibodies to the LPS of S. enteritidis as an indicator of infection is discussed.

Agglutination Tests↗
PubMed1990

An outbreak of Salmonella saint-paul infection associated with beansprouts.

In March 1988, there was an outbreak of infection by a strain of Salmonella saint-paul with a distinctive antigenic marker. A total of 143 reports were received between 1 March and 7 June. Preliminary investigations suggested that raw beansprouts were a possible source of infection and a case-control study confirmed the association. S. saint-paul of the epidemic type was isolated from samples of beansprouts on retail sale in different cities in the United Kingdom and from mung bean seeds on the premises of the producer who was most strongly associated with cases. In addition, Salmonella virchow PT34 was isolated from samples of raw beansprouts and was subsequently associated with seven cases of infection. Four other serotypes of salmonella were also isolated from beansprouts. On 8 April the public were advised to boil beansprouts for 15 seconds before consumption, and the premises of the one producer associated with many cases were closed. As a result of these actions there was a significant decrease in the number of infections with S. saint-paul.

Adolescent↗
PubMed1990

Plasmid profile typing can be used to subdivide phage-type 49 of Salmonella typhimurium in outbreak investigations.

Plasmid profile typing has been used to subdivide phage-type 49 of Salmonella typhimurium, the most common phage type in humans in England and Wales since 1985. Twenty profile patterns have been identified in 350 strains examined. Four profile patterns have been identified in 143 isolates from patients infected in 33 epidemiologically unrelated incidents and two patterns have predominated, ST49:62 and ST49:62, 1. These patterns were also common amongst S. typhimurium phage-type 49 isolated from cattle and poultry; however ST49:62 was more common in bovines whereas ST49:62, 1 predominated in poultry. S. typhimurium phage-type 49 with a different profile pattern, ST49:62, 3, was responsible for a large outbreak in London in 1988 which was traced to mayonnaise made from eggs supplied by one producer. Plasmid profile typing can now be regarded as a method of supplementing phage typing in investigating outbreaks caused by this organism.

Animals↗