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S McEwen

Publications and source records attributed to S McEwen.

16 recordsLinked to original sources
PubMed2006

Burden and cost of gastroenteritis in a Canadian community.

This study estimated the health burden and costs associated with gastroenteritis in the City of Hamilton (Ontario, Canada). The number of cases, number of different resource units used, and cost per resource unit were represented by probability distributions and point estimates. These were subsequently integrated in a stochastic model to estimate the overall burden and cost in the population and to depict the uncertainty of the estimates. The estimated mean annual cost per capita was Can dollar 115. The estimated mean annual cost per case was Can dollar 1,089 and was similar to other published figures. Gastroenteritis represented a significant burden in the study population, with costs high enough to justify prevention efforts. These results, currently the most accurate available estimates for a Canadian population, can inform future economic evaluations to determine the most cost effective measures for reducing the burden and cost of gastroenteritis in the community.

Canada↗
PubMed2004

Magnitude and distribution of acute, self-reported gastrointestinal illness in a Canadian community.

To estimate the magnitude and distribution of self-reported, acute gastrointestinal illness in a Canadian-based population, we conducted a retrospective, cross-sectional telephone survey of approximately 3500 randomly selected residents of the city of Hamilton (Ontario, Canada) from February 2001 to February 2002. The observed monthly prevalence was 10% (95 % CI 9.94-10.14) and the incidence rate was 1.3 (95 % CI 1.1-1.4) episodes per person-year; this is within the range of estimates from other developed countries. The prevalence was higher in females and in those aged < 10 years and 20-24 years. Overall, prevalence peaked in April and October, but a different temporal distribution was observed for those aged < 10 years. Although these data were derived from one community, they demonstrate that the epidemiology of acute gastrointestinal illness in a Canadian-based population is similar to that reported for other developed countries.

Acute Disease↗
PubMed2000

Inferring quality of life from performance-based assessments.

PURPOSE: Performance based measures have been suggested as an approach to estimate quality of life, but the associations have not been extensively evaluated. This study's purpose was to determine the associations between quality of life and performance based assessments of disablements in community dwelling individuals post-stroke. METHODS: Forty five people were evaluated in a cross-sectional pilot study. The subjects' quality of life (SF-36), ability in basic and instrumental activities of daily living (ADL), manual dexterity, mobility, neurological impairment, and perception of lateral neglect were evaluated. Multiple regression was employed to find the strongest associations. RESULTS: Neurological impairment explained 34% of the variation in the women's physical health summary score (PCS) of the SF-36. Instrumental ADL and neurological impairment together explained 66% of the women's mental health summary score (MCS) of the SF-36. Manual dexterity of the hemiplegic hand explained 39% of the variation in the men's PCS. CONCLUSION: Performance based measures may be useful to estimate quality of life in non-communicative individuals.

Aged↗
PubMed2000

Use of a Shiga toxin (Stx)-enzyme-linked immunosorbent assay and immunoblot for detection and isolation of Stx-producing Escherichia coli from naturally contaminated beef.

The purpose of this study was to evaluate an enzyme-linked immunosorbent assay (ELISA) and an immunoblot procedure for detection and isolation of Shiga toxin-producing Escherichia coli (STEC) from beef, and to correlate the presence of STEC in beef with E. coli and total coliform counts. A total of 120 samples of boneless beef supplied to a meat processor in southern Ontario were tested for the presence of STEC, E. coli, and total coliforms. Following enrichment in modified tryptic soy broth, samples were screened for Shiga toxin (Stx) by a Stx-ELISA and a Vero cell assay (VCA). Samples that were positive in the Stx-ELISA were subjected to the Stx-immunoblot for STEC isolation. Overall, 33.3% of samples were positive in the VCA, and 34.2% were positive in the Stx-ELISA. There was almost complete agreement between the Stx-ELISA and the VCA results (kappa = 0.98). The sensitivity and specificity of the Stx-ELISA with respect to the VCA were 100% and 98.75%, respectively. STEC were isolated by the Stx-immunoblot from 87.8% of the samples that were positive in the Stx-ELISA. The STEC isolates belonged to 19 serotypes, with serotype O113:H21 accounting for 10 of 41 isolates. No STEC of serotype O157:H7 were isolated. There was a significant correlation between E. coli counts and total coliform counts (Spearman correlation coefficient = 0.68, P < 0.01). The E. coli count was positively correlated with detection of STEC by both the Stx-ELISA and the VCA (P < 0.01).

Animals↗
PubMed1999

Pharmacokinetics of enrofloxacin given by the oral, intravenous and intramuscular routes in broiler chickens.

Enrofloxacin was given to broiler chickens, 3 groups of 6 birds each, at a dose of 5 mg/kg. Routes of administration were intravenous (i.v.), intramuscular (i.m.) and oral (p.o.) and blood samples were collected from the jugular vein for determination of serum drug levels over a 54-hour period after administration. Drug levels were determined using Bacillus subtilis spore suspension on Meuller-Hinton antibiotic medium. Intravenous administration produced drug levels which followed a bi-exponential decay according to the model C = 101e(-1.84(t)) + 1.30e(-0.06(t)). After i.m. administration, the mean Cmax observed (2.01 microg/mL) occurred at 1 h and levels were detected for up to 48 h. The mean time to maximum concentration (Tmax) for the birds occurred at 0.79 h. The model describing serum concentrations after i.m. administration was C = 1.35e(-0.48(t)) + 1.27e(-0.07(t)) - 2.06e(-2.1(t)). Serum concentrations after oral administration were lower and the mean +/- standard error of mean, of the maximum concentrations (Cmax) was 0.99 microg/mL at 2 h after administration. The mean residence times after the 3 routes of administration were not significantly different and ranged from 12.5-13.7 h. Bioavailability by the oral route was 80.1%. Dialysis of chicken plasma vs saline indicated that the protein binding was 22.7%.

Administration, Oral↗
PubMed1997

Persistence of Escherichia coli O157:H7 in dairy cattle and the dairy farm environment.

The persistence of Escherichia coli O157:H7 in cattle and the farm environment was investigated on eight Ontario dairy farms positive for E. coli O157:H7 in a longitudinal study commenced one year previously. Faecal samples from cows, calves, humans, cats, rodents, wild birds, a composite fly sample and numerous composite and individual environmental samples were cultured and tested for verotoxin-producing E. coli (VTEC). VTEC isolates were serotyped and E. coli O157:H7 isolates were phage typed. E. coli O157:H7 phage type 34 was isolated from one calf on each of two farms. The same phage type had been isolated on one of these farms 12 months earlier. Most E. coli O157:H7-positive animals and farms became culture-negative within 2 and 3 months, respectively. E. coli O157:H7 was not isolated from any environmental samples, although evidence of VTEC was found in composite samples from calf feeders (19.1%), calf barn surfaces (18%), cow feeders (14.9%), flies (12.5%), cow barn surfaces (11.3%), and individual milk filters (12.5%). VTEC belonging to 21 non-O157 serotypes were isolated from 24 cows (8.2%), 21 calves (18.3%), 2 cow feeder samples (3.0%), and 1 calf feeder sample (4.8%). Shedding of E. coli O157:H7 by infected dairy cattle appears to be transient and persistence of E. coli O157:H7 was not demonstrated from the farm environment sites tested.

Animals↗
PubMed1992

Polymerase chain reaction for detection of verocytotoxigenic Escherichia coli isolated from animal and food sources.

Animals and their by-products have been implicated as important sources of verocytotoxigenic Escherichia coli (VTEC) associated with disease in humans. VTEC comprise a wide range of serotypes and produce a variety of closely related verocytotoxins (VT). A pair of oligonucleotide primers, targeting conserved sequences found in VT1, VT2 and VTE genes, was used to develop a polymerase chain reaction (PCR) procedure to detect all types of VTEC. Supernatants of boiled broth cultures of VTEC (223 strains) isolated from ground beef, ground pork, raw milk, bovine faeces and porcine faeces; non-VTEC E. coli (72 strains); and other enteric and food bacteria (76 strains) were tested by PCR. The verocytotoxigenicity of these strains was verified by the Vero cell assay. All 223 VTEC isolates, comprising over 50 different serotypes, were detected by the PCR procedure. Shigella dysenteriae type 1 was the only other bacterium that was positive in this assay. As little as 1 pg of VTEC DNA and as few as 17 cfu of VTEC could be detected with this method. The results indicate that these primers detect VTEC over a wide range of serotypes. This method may be applicable as a screening procedure for the detection of VTEC in samples of foods and faeces.

Animals↗
PubMed1991

Alternatively spliced murine lyn mRNAs encode distinct proteins.

Two lyn proteins of 56 and 53 kDa have been observed in immunoprecipitates from a variety of murine and human cell lines and tissues. We report the cloning and nucleotide sequence of two distinct murine lyn cDNAs isolated from an FDC-P1 cDNA library. One of the cDNAs, designated lyn11, encodes a protein of 56 kDa which shares 96% similarity with human lyn. The other cDNA, designated lyn12, encodes a protein of 53 kDa. The proteins differ in the presence or absence of a 21-amino-acid sequence located 24 amino acids C terminal of the translational initiation codon. Using RNase protection analysis, we have identified mRNAs corresponding to both cDNAs in murine cell lines and tissues. Sequence analysis of murine genomic clones suggests that the distinct mRNAs are alternatively spliced transcripts derived from a single gene. Expression of both cDNAs in COS cells leads to the production of lyn proteins with the same molecular weight as the two forms of lyn proteins immunoprecipitated from extracts of FDC-P1 cells and mouse spleen. Subcellular fractionation studies and Western immunoblotting analysis suggest that both isoforms of lyn are membrane associated. The association of both lyn isoforms with the membrane fraction supports the notion that lyn, like other src-related kinases, may interact with the intracellular domain of cell surface receptors.

Amino Acid Sequence↗
PubMed1990

Prevalence of verocytotoxigenic Escherichia coli in ground beef, pork, and chicken in southwestern Ontario.

Samples of ground beef (225), pork (235) and chicken (200) were randomly selected from meat processing plants in the southwestern Ontario area. Supernatants of broth cultures of the samples were tested for verocytotoxins using a Vero cell assay. Neutralization of cytotoxic activity using antisera specific for three types of verocytotoxin (Verotoxin 1, Verotoxin 2 and Shiga-like toxin II) was performed on positive samples. Isolation of verocytotoxigenic Escherichia coli (VTEC) was attempted from positive samples. VTEC were confirmed as E. coli biochemically, tested for drug resistance, and serotyped. Based on neutralization studies, the prevalence of VTEC in beef and pork was at least 36.4% and 10.6%, respectively. This is much higher than has been reported from a survey of retail meats in which a method designed to detect only E. coli O 157.H7 was used. Isolations of VTEC were made from 10.4% of the beef samples and 3.8% of the pork samples. No VTEC were recovered from the chicken samples. The majority of VTEC isolates were susceptible to commonly used antimicrobial agents. A number of the serotypes of the VTEC isolates recovered have been associated with human disease; however, no VTEC of serotype O 157.H7 were isolated.

Animals↗
PubMed1987

Identical mRNA for preproglucagon in pancreas and gut.

The structure of the human glucagon gene and the sequence around the putative promoter region and transcriptional start site are shown. Cloning and sequencing of the cDNAs, coding for preproglucagon from human pancreas and colon, as well as primer extension analysis of RNA from pancreas, ileum and colon point to an identical transcriptional start site in all tissues, about 3 X 10(3) base pairs upstream from the first coding exon as defined by Bell et al.

Animals↗
PubMedDate not supplied

Semantic information is used by a deep dyslexic to parse compounds.

We report a case study of a 48 year-old patient, J.O., who was tested 20 years after the removal of a tumor in the left temporal-parietal region. This surgery and subsequent radiation resulted in right side paralysis and numerous language problems. Tests of J.O.'s single word reading abilities indicate that she could be classified as a deep dyslexic with over 16% of her errors in word naming having a clear semantic relationship with the target word (Coltheart, 1980). We examined her ability to read compound words aloud and following Libben (1993) we provide evidence that J.O. is a second case in which there is obligatory access of morphological constituents of compound words. These data are discussed within the context of Libben's (1998) compound word processing model.

Aphasia↗
PubMedDate not supplied

Disablement following stroke.

PURPOSE: Stroke is the most disabling chronic condition, newly affecting 35000 persons in Canada each year. Because of declining fatality, a growing number of persons will have to cope with stroke-related disability. The purpose of this paper is to describe the disabilities experienced by persons with stroke during the first year and explore the evolution of impairment, disability, handicap and health-related quality of life. SUBJECTS: The data for this paper come from a series of longitudinal and cross-sectional studies, collectively known as the McGill Stroke Rehabilitation Research Program. RESULTS: Within the first week post-stroke, getting out of bed and walking over a short distance, even with assistance, was a strong predictor of discharge home. Most of the improvement in measures of impairment and disability occurred during the first month and, by 3 months, there was still considerable room for improvement in all measures: 85% of persons were still impaired on gait speed, 78% had not reached age-specific norms for upper extremity function, 68% still demonstrated slow physical mobility, 37% needed some assistance with basic activities of daily living and 29% were still impaired on balance. By 1 year, 73% of persons scored the maximum for basic activities of daily living but 51 and 67% of persons reported their physical health and mental health to be lower than expected. Among a hardy group of stroke survivors, still living in the community 1 year post-stroke, the most striking area of difficulty was endurance, as measured by the 6 minute walk test. Those subjects well enough to complete this task (50% of sample) were able to walk, on average, only 250 metres, equivalent to 40% of their predicted ability. This series of snapshots taken at different points in time suggests that much of the improvement in impairment and disability occurs during the first month and then reaches a plateau. Handicap and quality of life continue to be issues later. Rehabilitation strategies need to consider the multifaceted nature of disablement, which in itself changes with time post-stroke.

Activities of Daily Living↗
PubMedDate not supplied

The effects of prehospital advanced life support drug treatment on patient improvement and in-hospital utilization.

OBJECTIVE: There is little published evidence to support the benefits of prehospital drug administration by ambulance personnel in reducing subsequent hospital utilization by the medical patients receiving such drugs. The authors studied the outcome of patients treated by Ontario's Emergency Health Services "Symptom Relief Drug Program," which was developed to relieve patient symptoms in the field for specific medical emergencies. METHODS: A retrospective study spanning a three-year period from January 1996 to December 1998 was undertaken in a mid-sized southern Ontario community. From a review of ambulance call reports (ACRs), eligible patients were recruited by mail and divided into two groups: those treated before the introduction of the program (pre) and those treated after (post). Out-of-hospital data were retrieved from ACRs and in-hospital data were gathered from medical chart reviews. Outcomes included emergency department (ED) length of stay (LOS), frequency of admissions, and departmental use. Secondary endpoints included differences in prehospital improvement, ED interventions, and ambulance scene times. RESULTS: For the unpaired analysis, 406 patients provided consent (pre: 215 vs post: 191). Ambulance time on scene was longer in the post group, 14.2 minutes (95%CI 13.7-14.8), versus the pre group, 12.3 minutes (95% CI 11.7-12.9), p < 0.001. A larger proportion of patients receiving prehospital drug treatment were judged to have improved on ED arrival (pre: 19.5% vs post: 48.2%, chi2 p < 0.0001). The ED LOSs did not differ between groups (pre: 206.9 min, 95% CI 185.9-230.4, vs post: 220.9 min, 95% CI 196.9-247.7, p = 0.42) but were shorter within the post group for hypoglycemic patients receiving glucagon. The overall proportion of admissions was significantly lower in the post group (pre: 145 [67.4%] vs post: 102 [54.3%], chi2 p < 0.01), and this was driven by chest pain patients. CONCLUSIONS: The lower rate of admissions for chest pain patients is the first published evidence of prehospital drug treatment's reducing hospital utilization in a sub-group of such medical patients. The "Symptom Relief Drug Program" is effective in improving patients' field conditions and can decrease ED LOS in hypoglycemic persons receiving glucagon injections. More outcome research pertaining to ambulance-administered prehospital drug treatment is warranted.

Aged↗