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B Bourke

Publications and source records attributed to B Bourke.

At least 55 records · Page 3Linked to original sources
PubMed1997

Staying on target.

In the area of market research, it's critical to be accurate and accumulate useful information, but it's also important to be cost-effective. Sometimes, a lot of planning and a little innovation can be the answer to obtaining the right information at the right price.

Computer Communication Networks↗
PubMed1997

Bedside manner.

The hospital setting can be a place of healing and hope for the future. Unfortunately, it can also be a site filled with pain and grief. How hospitals deal emotionally with patients, and others who experience trauma is an important aspect of overall care. The following is a look at the importance of compassionate care and how some Alabama hospitals tend to the emotional, psychological and spiritual needs of patients and their loved ones.

Alabama↗
PubMed1996

Characterization of Campylobacter upsaliensis fur and its localization in a highly conserved region of the Campylobacter genome.

Despite increasing recognition of the importance of Campylobacter upsaliensis in human disease little is known about either the virulence properties or genetics of this enteric pathogen. The complete coding sequence of a C. upsaliensis gene has yet to be published. We have cloned and sequenced the complete iron-uptake regulatory (fur) gene from the type strain of this species. The C. upsaliensis fur homolog was isolated from a genomic library of C. upsaliensis ATCC 43954 constructed in phage lambdaGEM-11. The open reading frame identified encodes a polypeptide consisting of 156 amino acids. The 5'-flanking region of the C. upsaliensis fur gene contains 3 putative Fur-binding sequences and two catabolite activator-binding sequences indicating the potential for autogenous and cAMP-mediated regulation, respectively. Primer extension analysis identified a single transcription start site 262 nt upstream from the AUG initiation codon. Sequence analysis indicates that the Fur protein of C. upsaliensis is highly homologous (87% amino acid identity) to Campylobacter jejuni Fur. Furthermore, the arrangement of the lysS and glyA genes downstream of fur is precisely conserved in both C. upsaliensis ATCC 43954 and C. jejuni TGH9011. Using the polymerase chain reaction close linkage of fur with lysS and glyA was also observed among multiple isolates of C. upsaliensis, C. jejuni and C. coli suggesting a possible functional relevance for this conserved genetic arrangement in campylobacteria.

Amino Acid Sequence↗
PubMed1996

Pulsed-field gel electrophoresis indicates genotypic heterogeneity among Campylobacter upsaliensis strains.

To determine the genomic relatedness among a selection of animal and human Campylobacter upsaliensis isolates, macrorestriction profiles were generated for 20 C. upsaliensis strains, among 7 serogroups, using pulsed-field gel electrophoresis (PFGE). XhoI, SalI and SacII restriction enzyme profiles indicated genomic heterogeneity among strains. Using XhoI and SacII restriction enzyme digestion, genomic similarities between some pairs of strains were Lior serogroup specific. The genomic sizes of these isolates varied from 1.74 to 2.09 Mb. These results demonstrate molecular heterogeneity of this species similar to that found among Helicobacter pylori isolates. Among C. upsaliensis strains, PFGE is highly discriminatory and should prove a useful molecular typing method for epidemiological purposes.

Animals↗
PubMed1996

Heterogeneity in phenotypic and genotypic characteristics among strains of Hafnia alvei.

Hafnia alvei is an emerging human pathogen associated with sporadic cases and outbreaks of diarrhea. Bangladeshi isolates of H. alvei possess the Escherichia coli attaching and effacing (eaeA) gene and demonstrate an attaching and effacing phenotype. In the present study we examined 11 Canadian H. alvei isolates and strain 19,982 from Bangladesh to determine if the formation of attaching and effacing lesions is a property shared among multiple isolates. Attaching and effacing lesions were detected by induction of tyrosine kinase protein phosphorylation and cytoskeletal rearrangements in infected tissue culture epithelial cells with immunofluorescence microscopy and by the examination of infected cells with transmission electron microscopy. The presence of the eaeA gene was examined by PCR and colony blot hybridization. Profiles of outer membrane protein extracts, chromosomal macrorestriction fragments, and plasmids were also examined. Accumulation of host phosphotyrosine proteins and rearrangement of the cytoskeletal protein alpha-actinin were both observed in HEp-2 cells infected with H. alvei 19,982. In contrast, none of the other 11 clinical H. alvei isolates demonstrated either of these responses, nor did they form attaching and effacing lesions under electron microscopy. Consistent with the absence of the attaching and effacing phenotype, these clinical isolates did not possess the eaeA gene. The outer membrane protein profiles of all the Canadian isolates were identical but differed from that of H. alvei 19,982. Pulsed-field gel electrophoresis and plasmid profile analyses of the clinical H. alvei isolates differed substantially from those of the Bangladeshi strain. These results indicate that there is heterogeneity among H. alvei strains with respect to signal transduction, attaching and effacing adhesion, outer membrane constituents, and genotype. Epidemiological studies on enteropathogenic H. alvei thus need to go beyond simple species designations and require specific identification of the virulent clones.

Actinin↗
PubMed1996

Byler-like familial cholestasis in an extended kindred.

Progressive familial intrahepatic cholestasis (PFIC) occurs in many communities and races. A form of PFIC in five children from two consanguineous marriages in an Irish kindred is described. In addition, a review of clinical information from the records of three deceased members of the kindred strongly implies that they also suffered from PFIC. The children had a history of neonatal diarrhoea, sepsis, and intermittent jaundice that ultimately became permanent. They suffered intractable pruritus and growth retardation. Despite evidence of severe cholestasis, serum gamma-glutamyl transferase and cholesterol were normal in these children. Sweat sodium concentration were raised in three children. Liver histology showed severe intrahepatic cholestasis and hepatocellular injury. Urinary bile acid analysis revealed a non-specific pattern consistent with chronic cholestasis. These children suffer from a form of PFIC remarkably similar to that occurring in members of the Byler kindred.

Bile Acids and Salts↗
PubMed1996

Gastric metaplasia and duodenal ulcer disease in children infected by Helicobacter pylori.

BACKGROUND: Helicobacter pylori infection of the gastric mucosa is vital in the pathogenesis of duodenal ulcer disease. H pylori will only colonise gastric epithelium and its association with duodenal disease is therefore not easily explained. AIMS: To determine if gastric metaplasia in the duodenum increases the risk of duodenal ulcer disease in children infected with H pylori. PATIENTS: All children undergoing upper endoscopy over a 20 month period in a children's hospital in Ireland. METHODS: Two biopsy specimens were obtained from the antral mucosa and two from the first part of the duodenum. One antral biopsy specimen was used in a rapid urease test (Clo Test). Biopsy sections were stained with haematoxylin and eosin and also with cresyl violet for identification of H pylori. Periodic acid Schiff (PAS) stain was performed to identify areas of gastric metaplasia. RESULTS: Gastric and duodenal biopsy specimens were obtained from 148 patients (M:F 1:2:1). Twenty five children (17%) had H pylori positive gastritis. Thirty four children (23%) had gastric metaplasia in the duodenum. Nine per cent of children under the age of 8 years had gastric metaplasia compared with 38% in those 12 years of age or over (p < 0.005). Seven children had duodenal ulcer disease. Gastric metaplasia was present in six of seven (86%) children with duodenal ulcer disease compared with 28 of 141 (20%) without ulceration (p < 0.001). While both H pylori and gastric metaplasia were each significant risk factors for duodenal ulcer disease, the combined presence of both factors was associated with a pronounced increase in duodenal ulcer disease. Duodenal ulcer disease occurred in over 50% of children with both H pylori infection and gastric metaplasia. In contrast duodenal disease did not occur in children (0 of 100) when both were absent. CONCLUSION: The presence of gastric metaplasia in the duodenum is the major risk factor for duodenal ulcer disease in patients colonised by H pylori.

Adolescent↗
PubMed1995

Physical and genetic map of the genome of Campylobacter upsaliensis.

A physical map of Campylobacter upsaliensis ATCC 43954 was constructed from DNA fragments generated by SalI (5' G/TCGAC), NarI (5' GG/CGCC) and BssHII (5' G/CGCGC) restriction digests separated using pulsed-field gel electrophoresis. The size of the C. upsaliensis genome was approximately 2000 kb, providing evidence of the largest Campylobacter genome sized to date. Twenty-one fragments created from these restriction digests were assembled into a physical map using a combination of complementary methods including cross-Southern hybridization, hybridization fingerprint analysis and hybridization with homologous and heterologous (from Campylobacter jejuni) gene probes. The position of ten genetic loci, including that of the iron-uptake regulatory (fur) gene, were localized to the physical map. A genomic library of C. upsaliensis ATCC 43954 was constructed in lambda Gem-11 vector. Fifty thousand recombinants with an average size of 16 kb represent a library about 200 times the size of the genome. Using C. jejuni DNA probes, clones representing C. upsaliensis flaA, fur and ftsZ genes were isolated and localized to the physical map.

Blotting, Southern↗
PubMed1995

An isoleucyl-tRNA synthetase gene from Campylobacter jejuni.

A complete isoleucyl-tRNA synthetase gene (ileS) of Campylobacter jejuni was isolated from a C. jejuni TGH9011 genomic DNA library constructed in pBluescript. The complete coding sequence, flanking regions and transcription start point were determined. The deduced isoleucyl-tRNA synthetase (IleRS) had 917 amino acids with a molecular mass of 105,399 Da, which was consistent with the observed size of 105 kDa in Escherichia coli maxicells. The ileS gene was mapped onto the physical map of the C. jejuni genome. Alignment of the C. jejuni IleRS sequence with six other bacterial IleRS sequences and two lower eukaryotic IleRS sequences identified seven conserved motifs, including the two signature sequences, HIGH and KMSKS, of class I aminoacyl-tRNA synthetases.

Amino Acid Sequence↗
PubMed1992

Progression from partial to generalised lipodystrophy--a case report.

Lipodystrophies are rare disorders of adipose tissue metabolism. Two forms are recognised--partial or generalised. Though loss of body fat is a common feature these have been considered mutually exclusive clinical entities making any unifying pathophysiological concept difficult. We report, for the first time, a case of partial lipodystrophy affecting the face which progressed to become generalised.

Adult↗