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A McNabb

Publications and source records attributed to A McNabb.

9 recordsLinked to original sources
PubMed2006

Distribution and characterization of Borrelia burgdorferi isolates from Ixodes scapularis and presence in mammalian hosts in Ontario, Canada.

The blacklegged tick, Ixodes scapularis Say (Acari: Ixodidae), has a wide geographical distribution in Ontario, Canada, with a detected range extending at least as far north as the 50th parallel. Our data of 591 adult I. scapularis submissions collected from domestic animals (canines, felines, and equines) and humans during a 10-yr period (1993-2002) discloses a monthly questing activity in Ontario that peaks in May and October. The Lyme disease spirochete Borrelia burgdorferi Johnson, Schmidt, Hyde, Steigerwalt & Brenner was detected in 12.9% of I. scapularis adults collected from domestic hosts with no history of out-of-province travel or exposure at a Lyme disease endemic area. Fifty-three isolates of B. burgdorferi were confirmed positive with polymerase chain reaction by targeting the rrf (5S)-rrl (23S) gene. Using DNA sequencing of the ribosomal species-specific rrf (5S) -rrl (23S) intergenic spacer region, all isolates belong to the pathogenic genospecies B. burgdorferi sensu stricto (s.s.). Nucleotide sequence analysis of a 218- to 220-bp amplicon fragment exhibits six cluster patterns and, collectively, these isolates branch into four phylogenetic cluster groups for both untraveled, mammalian hosts and those with travel to the northeastern United States (New Jersey and New York). Four of five geographic regions in Ontario had strain variants consisting of three different genomic cluster groups. Overall, our molecular characterization of B. burgdorferi s.s. shows genetic heterogeneity within Ontario and displays a connecting link to common strains from Lyme disease endemic areas in the northeastern United States. Moreover, our findings of B. burgdorferi in I. scapularis reveal that people and domestic animals may be exposed to Lyme disease vector ticks, which have wide-ranging distribution in eastern and central Canada.

Animals↗
PubMed2003

Mapping the range and scope of emergency nurse practitioner services in the Northern and Yorkshire Region: a telephone survey.

OBJECTIVE: To map the range and scope of emergency nurse practitioner (ENP) services in the Northern and Yorkshire Region as part one of a three phased study investigating the developing role of the ENP on a multi-professional context. METHODS: A telephone survey was conducted in the 48 hospital trusts within the region. Semi-structured interviews were arranged with the senior nurses responsible for accident and emergency services in responding departments. Data collection entailed completion of a form comprising 14 open-ended questions designed to elicit information about the range and scope of ENP services (as defined by the Royal College of Nursing). Data were analysed using descriptive statistics. RESULTS: Interviews were conducted at 35 (73%) of the sites, 22 (63%) of which had an ENP service as defined above. Wide variation was found in the range of services in relation to: hours/days of availability; age range and sources of referrals of patients accessing the service; clinical caseloads of ENPs and the referral pathways to other services. CONCLUSION: The findings from the survey highlight the organic, context specific nature of ENP role developments in response to national government initiatives, professional agendas, and local service needs.

Age Factors↗
PubMed1997

Human isolates of Staphylococcus caprae: association with bone and joint infections.

Staphylococcus caprae is a coagulase-negative, DNase-positive member of the genus Staphylococcus usually associated with goats, but since 1991 a few laboratories have reported isolating the organism from human clinical specimens. We report on the isolation of 14 strains from human specimens and note that 10 strains were obtained from patients with bone and joint infections. Nine of the 10 infections started with traumatic fractures, and the other was a case of mastoiditis. Seven of these 10 infections were in patients with orthopedic prostheses, which appears to be a risk factor. Three of the 14 strains were from transplant patients. For three of the patients, S. caprae was the only organism isolated. S. caprae may be misidentified because it is not represented in the current MicroScan or Vitek identification systems which are in use in many laboratories, but the organism can be differentiated by a few biochemical tests. S. caprae produces positive results for DNase, pyrrolidonyl aminopeptidase, and acid production from mannitol and maltose; it produces negative results for ornithine decarboxylase and tube coagulase.

Adolescent↗
PubMed1997

Fatty acid characterization of rapidly growing pathogenic aerobic actinomycetes as a means of identification.

The fatty acid compositions of 39 type strains and 529 clinical or reference strains of pathogenic aerobic actinomycetes were analyzed after standardized culture by using the Microbial Identification System (MIS). Library entries for each type strain were created by using the MIS Library Generation Software, and the fatty acid profiles of clinical and reference strains were compared to these library entries. The bacteria separated into two large groups based upon major amounts of branched-chain or of saturated or monounsaturated straight-chain fatty acids. Identification of isolates was possible by using only the type strains for comparison, but fatty acid heterogeneity occurred within most species.

Actinomycetaceae↗
PubMed1997

Recognition of a Nocardia transvalensis complex by resistance to aminoglycosides, including amikacin, and PCR-restriction fragment length polymorphism analysis.

Amikacin resistance, rare among nocardiae, was observed in 58 clinical isolates of nocardiae. All of these isolates hydrolyzed hypoxanthine, and 75 to 100% utilized citrate, D-galactose, and D-trehalose as sole carbon sources. Based on utilization of I-erythritol, D-glucitol, i-myo-inositol, D-mannitol, and ribitol and susceptibility to amoxicillin-clavulanic acid, the 58 isolates were separable into four groups. One group was negative for I-erythritol and ribitol and included all the isolates belonging to Nocardia asteroides complex antibiogram type IV. The remaining three groups were positive for I-erythritol and ribitol and were grouped within Nocardia transvalensis. The group that included the type strain was designated N. transvalensis sensu stricto, and the other two groups were designated new taxons 1 and 2. PCR-restriction fragment length polymorphism (RFLP) analysis of a 439-bp segment of the 65-kDa heat shock protein gene with XhoI and HinfI produced identical patterns for 53 (91%) and 58 (100%) isolates, respectively, and differentiated them from all other Nocardia taxa. NarI- and HaeIII-derived RFLP patterns clearly differentiated each of the four biochemically defined taxa. These four groups were also distinguishable by using the chromogenic substrates in Dade MicroScan test panels. By high-performance liquid chromatography, these isolates exhibited the same unique mycolic acid-ester elution patterns that differed from those of all other clinically significant nocardiae. Gas-liquid chromatographic analysis of fatty acids also produced similar patterns for all isolates that distinguished them from all other Nocardia taxa, but did not differentiate the four taxa within the complex. We propose the designation N. transvalensis complex for these four groups of nocardiae, pending further genetic evaluation.

Amikacin↗
PubMed1996

Identification of staphylococci with a self-educating system using fatty acid analysis and biochemical tests.

We characterized all of the 35 aerobic taxa of the genus Staphylococcus by using an objective, self-learning system combining both whole-cell fatty acid (FA) analysis and the results of 35 biochemical tests. Isolates were compared with the type strain for each taxon to generate an FA profile library and a biochemical table of test responses. Isolates were accepted into the system if they had a similarity index of > or = 0.6 for a taxon within the FA profile library and if they were identified as the same taxon by a computer program using a probability matrix constructed from the biochemical data. These stringent criteria led to acceptance of 1,117 strains assigned to legitimate taxa. Additional FA groups were assembled from selected strains that did not meet the inclusion criteria based on the type strains and were added to the system as separate entries. Currently, 1,512 isolates have bee accepted into the system. This approach has resulted in a comprehensive table of biochemical test results and a FA profile library, which together provide a practical system for valid identifications.

Aerobiosis↗
PubMed1988

Flux ratio theorems for nonlinear membrane transport under nonstationary conditions.

We extend flux ratio theorems concerning ratios of unidirectional flux transients passed (in complementary experiments) through a medium of spatially inhomogeneous transport properties pertaining to diffusion, migration and temporary trapping of the transported substance. Any nonlinearity in the transport equations leads to a breakdown of the Ussing flux ratio theorem pertaining to all times. An integrated flux ratio theorem is proved for the case when the nonlinearity is in the kinetics of trapping, as when trapping sites can be saturated. The new theorem is shown to fail when the nonlinearity is due to a concentration-dependence of the diffusion coefficient, as in facilitated transport. The nature of a nonlinearity in membrane transport can therefore be elucidated experimentally by the use of the integrated flux ratio.

Animals↗