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A Gilmour

Publications and source records attributed to A Gilmour.

At least 37 records · Page 2Linked to original sources
PubMed1995

Incidence of Listeria spp. and Listeria monocytogenes in a Poultry Processing Environment and in Poultry Products and Their Rapid Confirmation by Multiplex PCR.

Volume 60, no. 12, p. 4602: Fig. 1 should appear as shown below. FIG. 1. Incidence of L. monocytogenes and other Listeria spp. in a poultry processing environment and in raw and cooked poultry products from March to September 1992. (A) Raw (R) and cooked (C) areas within the processing environment. (B) Raw and cooked poultry products. (box), L. monocytogenes; (box), Listeria spp. (not L. monocytogenes); (symbl), no Listeria spp. [This corrects the article on p. 4600 in vol. 60.].

Journal Article↗
PubMed1995

Characterization of Listeria monocytogenes isolated from poultry products and from the poultry-processing environment by random amplification of polymorphic DNA and multilocus enzyme electrophoresis.

A total of 289 Listeria monocytogenes strains isolated from a poultry-processing environment and poultry products over a 6-month period were characterized by random amplification of polymorphic DNA, (RAPD) to pinpoint sources of contamination within the plant and gain some measure of the persistence of individual genotypes within this environment. Eighteen RAPD profiles (A through R) were identified within this group, with 64% (184 of 289) of all strains displaying a single RAPD profile, RAPD type A. This genotype was more prevalent in the raw-poultry-processing environment, where, although its origin within this environment appeared to be the incoming birds, it was also widespread on food contact surfaces, floors, and drains. This was the only genotype which persisted throughout the entire 6-month period, and it and RAPD type B were the only two genotypes found in both the raw- and cooked-poultry-processing environments. L. monocytogenes strains isolated from cooked poultry products and the cooked-poultry-processing environment up to 1 year later (17 strains) contained only RAPD types A and B, highlighting the potential which exists for persistent strains to cross-contaminate foods processed in that environment. The other genotypes (C through R) occurred more sporadically, suggesting varied sources of contamination. These were confined to either the raw- or the cooked-poultry-processing environment and were relatively short-lived. Further characterization of a selection of RAPD type A strains, together with strains of RAPD types B through R, was carried out by multilocus enzyme electrophoresis. Strains of RAPD type A contained two electrophoretic types, one of which was serotype 1/2a and the other was 1/2c.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

The effects of softwater acclimation on respiratory gas transfer in the rainbow trout Oncorhynchus mykiss

Gill O2 uptake, CO2 excretion, ventilation and blood respiratory/acid&shy;base variables were evaluated in control and softwater-acclimated trout (Oncorhynchus mykiss) to test the hypothesis that gill chloride cell (CC) proliferation, elicited by 2 weeks of softwater exposure, impairs the diffusion of respiratory gases across the gill. The proliferation of CCs in softwater fish was verified using light microscopy, and its impact on respiratory gas transfer was assessed in vivo by continuous monitoring of arterial blood PO2 (PaO2), PCO2 (PaCO2) and pH (pHa) using an extracorporeal blood circulation under conditions of normoxia and graded hypoxia [water PO2 (PwO2) was lowered from 20.0 kPa to 5.3 kPa within 20 min]. During normoxia, ventilation frequency was significantly higher in the softwater trout (78&plusmn;4 versus 57&plusmn;4 breaths min-1; mean &plusmn; s.e.m.), while ventilation amplitude was similar in both groups (1.0&shy;1.1 cm opercular displacement). PaCO2 and plasma HCO3- concentration were significantly lower in the softwater fish and the blood acid&shy;base status was characterized by a mixed respiratory alkalosis and metabolic acidosis such that blood pH was not statistically different between the two groups. CO2 excretion (2.5&shy;2.8 mmol kg-1 h-1) and O2 uptake rates (2.3&shy;5.1 mmol kg-1 h-1), as measured during normoxia, were unaffected by acclimation to soft water. During hypoxia, ventilation frequency and amplitude increased in the control trout, whereas only ventilation amplitude increased in the softwater-acclimated fish. The rate of PaO2 reduction during hypoxia was significantly greater in the softwater fish (0.84&plusmn;0.06 versus 0.65&plusmn;0.06 kPa PaO2 kPa-1 PwO2) and, at the most severe level of hypoxia (PwO2=5.3 kPa), PaO2 was significantly lower in the softwater fish. The rate of PaCO2 reduction (caused by hyperventilation) was significantly lower in the softwater-acclimated fish (0.002&plusmn;0.001 versus 0.005&plusmn;0.001 kPa PaCO2 kPa-1 PwO2; mean &plusmn; s.e.m.; P<0.06) and, indeed, was not statistically different from zero. Blood pH did not change significantly during hypoxia in either group but, through much of the hypoxic period (7&shy;15 kPa PwO2), pHa was statistically lower in the softwater-acclimated fish. These results demonstrate that exposure of trout to soft water for 2 weeks is associated with proliferation of lamellar CCs and impaired branchial gas transfer. Hyperventilation was identified as a compensatory physiological adjustment.

Journal Article↗
PubMed1994

A non-isotopic DNA hybridisation assay for the identification of Staphylococcus aureus isolated from foods.

A digoxygenin-labelled total genomic DNA probe was used to identify Staphylococcus aureus. Isolation and identification of organisms was possible in less than 4 days. Identification alone could be completed in less than 2 days, compared with over 5 days for identification of isolates by multipoint inoculation. The probe showed excellent discrimination of S. aureus from other staphylococci and from a wide range of bacteria commonly associated with milk and meat. The effectiveness of this probe was tested against cultural isolation of staphylococci in milk using Baird-Parker agar followed by identification using multipoint inoculation and API Staph. The probe gave comparable results to the conventional methods and, for large sample numbers, offered lower cost and greater ease of use.

Animals↗
PubMed1994

Some factors inhibiting amplification of the Staphylococcus aureus enterotoxin C1 gene (sec+) by PCR.

PCR amplification of the sec+ gene for staphylococcal enterotoxin C1 (SEC1) can be achieved from as little as 10 fg total genomic DNA (equivalent to less than 10 cells) using two nested primer pairs. The presence of bacterial cells, particularly thermonuclease-producing staphylococci, and the thermonuclease enzyme (TNase) itself, were found to be factors which individually and together reduced the sensitivity of PCR amplification.

DNA, Bacterial↗
PubMed1994

Incidence of Listeria spp. and Listeria monocytogenes in a poultry processing environment and in poultry products and their rapid confirmation by multiplex PCR.

The incidence of Listeria spp. and Listeria monocytogenes in a poultry processing plant and in raw and cooked poultry products was determined over a 6-month period. Within the raw and cooked poultry processing environments, 46% (36 of 79) and 29% (51 of 173) of the samples contained Listeria spp. while 26% (21 of 79) and 15% (27 of 173) contained L. monocytogenes, respectively. Various sites within the processing environment were found to be consistently positive for L. monocytogenes throughout the entire sampling period. Of the raw and cooked products tested, 91% (53 of 58) and 8% (8 of 96) were found to contain Listeria spp. while 59% (34 of 58) and 0% (0 of 96) contained L. monocytogenes, respectively. Although L. monocytogenes was not detected in the cooked products examined, the presence of other Listeria spp. highlights the potential which exists for postprocessing contamination. Multiplex PCR proved to be a convenient and time-saving technique for rapid confirmation of Listeria spp. and L. monocytogenes in a single reaction.

Animals↗
PubMed1994

Application of multilocus enzyme electrophoresis and restriction fragment length polymorphism analysis to the typing of Listeria monocytogenes strains isolated from raw milk, nondairy foods, and clinical and veterinary sources.

The powerful discriminatory typing capabilities of multilocus enzyme electrophoresis and restriction fragment length polymorphism analysis were applied to Listeria monocytogenes strains from raw milk, nondairy foods, and clinical and veterinary sources. The raw milk and nondairy food strains were sequential isolates obtained over a year-long period from a number of different producers and manufacturers. Results obtained by the two typing methods were in substantial agreement and showed that both raw milk and nondairy foods frequently contain recurrent L. monocytogenes strains, thus suggesting that the presence of these organisms in such commodities often arises because of contamination from within their respective processing environments. Most recurrent strains were serogroup 1/2, with only one instance of recurrent serogroup 4 strains. Some recurrent L. monocytogenes strains, including the serogroup 4 strains, were found by analysis of multilocus enzyme electrophoresis results to be closely related to clinical and veterinary strains, thus suggesting that strains adapted for survival in the food-processing environment retain their potential for pathogenicity.

Animals↗
PubMed1993

Occurrence and characteristics of Listeria in foods produced in Northern Ireland.

The incidence of L. monocytogenes and other Listeria species was determined for 513 food samples produced in Northern Ireland. Selected L. monocytogenes isolates were typed using MEE and RFLP analysis. The overall incidence of Listeria in the foods examined was 35% (Listeria monocytogenes 18.3%). The incidence of Listeria and L. monocytogenes in four different food categories (graded I-IV according to decreasing extent of processing) being: I, 11.1% Listeria and 4.7% L. monocytogenes; II, 27.1% Listeria and 12.2% L. monocytogenes; III, 89.1% Listeria and 50% L. monocytogenes and IV, 100% Listeria and 100% L. monocytogenes. Within food categories I and II, the incidence of Listeria on occasions varied markedly between similar products produced by different processors. The most frequently isolated species was L. innocua, followed by L. monocytogenes, L. seeligeri and L. welshimeri. The L. monocytogenes isolates were predominantly serogroup 1. A modified USDA method was the most productive of four enrichment procedures investigated. Over the one-year duration of the survey, a distinctive Listeria microflora could be discerned in products from certain processors and was confirmed in some cases by MEE and RFLP typing of L. monocytogenes isolates.

DNA, Bacterial↗
PubMed1993

Oestrogen receptor expression in ductal carcinoma in situ of the breast: relationship to flow cytometric analysis of DNA and expression of the c-erbB-2 oncoprotein.

The expression of oestrogen receptor protein (ER) was examined in 151 cases of symptomatic or screening detected pure ductal carcinoma in situ (DCIS) of the breast by immunocytochemical assay (ERICA), in formalin-fixed paraffin-embedded tissue, with the monoclonal antibody H 222 (Abbott). Forty-eight tumours (31.8%) of cases were ER positive. Twenty-seven (17.9%) of cases showed high level ER expression and 21 (13.9%) of cases showed low level ER immunoreactivity. Significant associations of positive tumour ER immunoreactivity and non-comedo architecture chi 2 = 6.76; (d.f. = 1): P < 0.001, small cell size chi 2 = 4.49; (d.f. = 1): P = 0.034, higher S-phase fraction chi 2 = 4.71; (d.f. = 1): P = 0.03 and lack of c-erbB-2 protein overexpression chi 2 = 7.96; (d.f. = 1): P < 0.01 were identified. No significant associations of ER expression and patient age, histological grade of necrosis in DCIS, or DNA ploidy were found. ER expression is detectable in less than one third of symptomatic and screening detected cases of DCIS, implying that endocrine therapy of DCIS may be a more appropriate form of management for morphological subtypes of DCIS which show higher rates of oestrogen receptor expression, particularly those of non-comedo and small cell type.

Adult↗
PubMed1993

Development of a random amplification of polymorphic DNA typing method for Listeria monocytogenes.

The 10-mer primer OPM-01 (5'-GTT GGT GGC T-3') was used to generate random amplification of polymorphic DNA (RAPD) profiles by polymerase chain reaction for 91 strains of Listeria monocytogenes from raw milk, food, and veterinary, medical, and food-environmental sources. The profiles obtained contained 1 to 10 bands within the molecular size range of 0.5 to 5.0 kbp. Reproducibility was enhanced by annealing at low stringency and introducing a 1-min ramp time between annealing and extension temperatures. Thirty-three RAPD profiles were observed, with specific profiles being observed for strains from each source. RAPD profiles allowed discrimination within serogroups, although five RAPD profiles which were not confined to one serotype were found. Within food strains, one RAPD profile was more common than others, suggesting this to be a common type among strains from this source.

Bacterial Typing Techniques↗
PubMed1992

Occurrence of Listeria species in raw milk and dairy products produced in Northern Ireland.

The overall incidence of Listeria spp. in raw milk samples surveyed was found to be 25.0% (Listeria monocytogenes 15.3%), with the incidence in samples from processing centres 54.0% (L. monocytogenes 33.3%); this was higher than that in samples from dairy farms (Listeria spp. 8.8%; L. monocytogenes 5.3%). The FDA enrichment procedure was much more productive than cold enrichment and Oxford agar was superior to modified McBride agar for isolation of Listeria. Listeria monocytogenes was never isolated by direct plating of raw milk samples on Oxford agar at a detection level of 1.0 cfu/ml. Listeria spp. were isolated from 1 of 95 pasteurized milk samples (L. monocytogenes) and 1 of 33 soft cheese samples (L. seeligeri). Restriction fragment length polymorphism was more useful than sero- or phage-typing for typing of L. monocytogenes strains, and results suggest that specific L. monocytogenes strains may persist in both farm and processing environments.

Animals↗
PubMed1992

Resin-bonded bridges: 2. Treatment planning, clinical gases and failures.

This is the second paper in the two-part series which considers the developments and clinical techniques of resin-bonded bridges with the emphasis on methods for increasing success from a functional and aesthetic view point. Part 1 focused on the development and types of resin-bonded bridge and tooth preparation. This article describes the clinical application of this type of bridge and discusses failures.

Adolescent↗
PubMed1991

Detection of enterotoxigenic Staphylococcus aureus in dried skimmed milk: use of the polymerase chain reaction for amplification and detection of staphylococcal enterotoxin genes entB and entC1 and the thermonuclease gene nuc.

The polymerase chain reaction was used to amplify the staphylococcal enterotoxin B and C genes (entB and entC1) and the staphylococcal nuclease gene (nuc). Two sets of primers ("nested primers") were found to be necessary for the detection of low copy numbers of purified DNA in diluent. These allowed detection of ca. 1 fg of purified target DNA, while 100 pg was required before detection of entB, entC1, and nuc with single primer pairs was possible. With nested primers, enterotoxigenic Staphylococcus aureus cells could be detected in artificially contaminated dried skimmed milk samples at levels of ca. 10(5) CFU ml-1 within 8 h. No cross-reaction was observed between the highly homologous entB and entC1 genes. The method showed total specificity for entC1 when tested against a wide variety of other bacteria.

Animals↗
PubMed1990

Isolation and identification of staphylococci from milk powders produced in Northern Ireland.

Milk powders (37 samples) from five different processing centres (A, B, C, D and E) were examined for total viable counts, total staphylococcal counts and staphylococcal enterotoxins. All powders from centres A, B and C contained low numbers of total viable bacteria and staphylococci but five from centres D and E had high total and staphylococcal counts. Nine different staphylococcal species were encountered in low count powders with a wide range of species occurring at each of the five centres. Three species (Staphylococcus capitis, Staph, saprophyticus and Staph. cohnii) were found whose natural hosts are humans. High count powders all contained added fat of various types and had a much more restricted staphylococcal microflora in which Staph. saprophyticus and Staph. cohnii predominated. None of 384 staphylococcal strains isolated were found to be Staph. aureus. In addition, no enterotoxins were detected.

Animals↗
PubMed1989

An observation of DNA ploidy, histological grade, and immunoreactivity for tumour-related antigens in primary and metastatic breast carcinoma.

A cohort of 36 cases of advanced breast carcinoma were included in the study. DNA ploidy, histological grade, and immunoreactivity for carcino-embryonic antigen (CEA), carcino-embryonic antigen with normal cross-reacting antigen (CEA/NCA), and to NCRC-11 were assessed in primary breast carcinomas and metastases from the ovary and axillary lymph nodes. Changes in these variables between primary tumours and their metastases were found in 44 per cent of cases for DNA ploidy, 44 per cent of cases for histological grade, 17 per cent of cases for immunoreactivity to NCRC-11, 28 per cent of cases for CEA, and 56 per cent of cases for CEA/NCA immunoreactivity, respectively. Alteration of one factor appeared to be independent of changes in other factors. The development of clones with metastatic potential does not appear to be related to consistent changes in any one of the factors examined and suggests that none of these factors would be of prognostic value in advanced breast carcinoma.

Antibodies, Monoclonal↗
PubMed1989

Factors influencing the detachment of a polymer-associated Acinetobacter sp. from stainless steel.

The role of an extracellular polymer secreted by an Acinetobacter sp. attached to stainless steel was investigated. Parameters expected to influence polymer conformation, viz. temperature, pH, ionic strength and the concentration of calcium and magnesium ions, were altered and the resulting detached bacteria enumerated. Increasing both the temperature and pH resulted in increased numbers of bacteria detached. The effects of increasing the concentration of sodium chloride up to 100 mM and magnesium or calcium chloride up to 30 mM were small and, although statistically significant, were considered unlikely to have had major influence on the association of the bacteria with the stainless steel surfaces. Treatments including ultraviolet irradiation of surface-associated bacteria always resulted in removal of greater numbers of bacteria when compared to treatments where irradiation was not employed. The results indicate that an adhesive extracellular acidic polysaccharide may mediate the attachment of the Acinetobacter sp. to stainless steel.

Acinetobacter↗