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Two laboratory studies involving 11 laboratories were undertaken to assess the performance of North American Porcine circovirus-2 (PCV-2) polymerase chain reaction (PCR) assays. Laboratories received identical submissions containing randomly coded positive and negative control samples, and serially diluted PCV-2-spiked samples. In study 1 and 2, respectively, spiked samples contained measured amounts of PCV-2 virus or DNA. All but 1 assay detected DNA in the most concentrated spiked sample. There were no statistical differences in the proportion of positive or negative samples reported by quantitative (n = 7) versus non-quantitative (n = 6) assays. Across both studies, the false positive rate was 17% (4 out of 23), and 17% (2 out of 12) of assays cross-reacted with PCV-1. The most sensitive assay detected PCV-2 DNA levels about 100 000 times lower the least sensitive assay. This study demonstrated that the PCR assays available in North American diagnostic labs vary considerably in their detection limits and quantification.

Every year, thousands and thousands of people from Asia, most of them PhDs, make the ultimate transition in their lives when they travel to the west to take up fellowship positions (in this case a research fellowship position) in leading labs in North America and Europe. Many of these people travel with their families, not knowing what is coming their way. In this article, a number of issues have been discussed that might help these potential scientists of the future to plan ahead for such a shift and make their transition as smooth as possible.

Objective: To serve as a guideline for health care providers on the use of continuous and extended combined hormonal contraception regimens, to prevent pregnancy, and to delay menses that affect health-related quality of life., Options: All combined hormonal contraceptive methods available in Canada that may be used in a continuous or extended regimen are reviewed, and the implications are discussed., Outcomes: Efficacy of cited regimens and assessment of their side effects, patient safety, medical usage and non-contraceptive benefits, cost-effectiveness, and availability in Canada. Indications for patient counselling are also provided., Evidence: Medline, PubMed, and Cochrane Database were searched for articles published in English between 1977 and May 2007. Relevant publications and position papers from appropriate reproductive health and family planning organizations were also reviewed., Values: The quality of evidence is rated using the criteria described by the Canadian Task Force on Preventive Health Care (Table 1)., Benefits, Harms, and Costs: The guideline is intended to help reduce unintended pregnancies and improve health-related quality of life in women who find their menses problematic. Increased awareness and empowerment of women, their partners, and health care professionals will improve their ability to make appropriate choices between continuous or extended and cyclic usage of these regimens., Sponsors: The development of this guideline has been supported by unrestricted grants from Bayer HealthCare Pharmaceuticals, Janssen Ortho, Organon Canada Ltd., Paladin Labs Inc., Pfizer Canada Inc., and Wyeth Pharmaceuticals.

In his book, The Organization of Behavior, Donald Olding Hebb introduced the concepts of synaptic plasticity and cell assemblies to provide a theory of the neurophysiological basis of behaviour. Hebb's ideas, as presented in this book and other writings, influenced all areas of psychology and neuroscience. Hebb was born in Chester, Nova Scotia, Canada and attended Dalhousie University (BA, 1925) and McGill University (MA, 1932). His PhD from Harvard in 1936 was supervised by Karl Lashley. Hebb worked with the neurosurgeon Wilder Penfield at the Montreal Neurological Institute for two years, taught at Queen's University in Kingston, Ontario, and was a research assistant with Lashley at the Yerkes Primate Labs in Florida before he became a professor of Psychology at McGill University in 1947. At McGill he taught the first year psychology course and wrote an introductory textbook in Psychology. Throughout his career, Hebb made many research discoveries, trained a number of researchers and won many honours. When he retired from McGill, he moved back to Nova Scotia, and became a Professor Emeritus at Dalhousie University. This paper reviews Hebb's life and work and the impact of his ideas in psychology and neuroscience.

A monoclonal antibody (MAb)-based antigen capture enzyme-linked immunosorbent assay (ELISA) was compared with the routine culture methodology for the detection of Campylobacter fetus subspecies from bovine and ovine field samples inoculated into Clark's transport enrichment medium (TEM). The work was a collaboration between two different diagnostic laboratories, one in Canada and the other in England. In both labs, TEM samples were incubated for 4 days at 35 degrees C and then tested by culture and ELISA. The ELISA consisted of initial screening with MAb M1825 against C. fetus subspecies core lipopolysaccharide (LPS). All samples positive on ELISA screening were then retested by ELISA with MAb M1825 and MAbs M1177, M1183, and M1194, which recognize serotype A- and/or serotype B-specific C. fetus subspecies LPS epitopes. The Canadian samples consisted of 1,060 preputial washings from 529 bulls, of which 18 were positive by both culture and ELISA and 1,042 were negative by both methods. The English samples consisted of 321 tissue specimens, mostly stomach contents and placentas, from 190 aborted ovine and bovine fetuses. A total of 262 samples were negative by culture and ELISA, 52 samples were positive by culture and ELISA, and 7 samples were culture negative but ELISA positive. The results for all 70 culture-positive isolates were confirmed by conventional biochemical methods as C. fetus subsp. fetus, with 39 presumptively identified by the ELISA as serotype A and 30 presumptively identified as serotype B and with one sample containing isolates presumptively identified as serotype A and serotype B. A receiver operating characteristic analysis of the combined ELISA data from both countries resulted in an area under the curve of 0.997, with a sensitivity of 100% and a specificity of 99.5% relative to the results of culture. The data confirm that this ELISA method can be used as an excellent test for the screening of field samples in TEM for the presence of C. fetus subspecies.

Previous studies suggest elevated factor VIII is a common, independent risk factor for venous thromboembolism (VTE); however, these studies included secondary and idiopathic VTE. We sought to explore the association between elevated factor VIII and VTE in Canadian patients with idiopathic thrombosis, and confirm the current upper factor VIII reference range was appropriate. We enrolled 300 consecutive patients with idiopathic VTE who were matched to friend controls by age, sex and ethnicity. Factor VIII levels were measured and compared between cases and controls. The optimal cut-off value to designate factor VIII levels as elevated was determined using a variety of methods. The optimal upper cut-off value for factor VIII levels was 270 IU/dl. In the logistic regression analysis, cases were more likely to have elevated factor VIII levels (OR:8.76), as were females (OR:1.93) and older subjects (OR: 1.05). Factor VIII cutoffs for a 95% specificity by age were 238 IU/dl for subjects <40 years, 248 IU/dl age 40-55 years, 261 IU/dl age 56-70 years, and 313 IU/dl age >70. Our findings confirm that elevated factor VIII is associated with an increased risk of idiopathic VTE. In our patients and matched controls, the current upper limit of normal (150 IU/dl) for factor VIII is not of clinical use. We propose that the upper limit be increased to 270 IU/dl or individual labs should establish their upper limit if they wish their assays to be discriminatory in patients with VTE. Age specific cut-offs may be clinically relevant.

Many laboratories with cavity chambers as primary standards for air kerma are considering using additional Monte Carlo calculated correction factors, in particular the correction for attenuation and scatter in the walls, Kwall, and possibly the correction for point of measurement, Kan. Standards labs also use Monte Carlo calculated Spencer-Attix stopping-power ratios for graphite to air. The purpose of this article is to investigate the sensitivity of these calculations to their details and to assign uncertainties to the calculated values. We also investigate the correction needed for the Canadian primary standard to account for a polystyrene insulator, Kcomp and find that it is quite large (1.0046 +/- 0.0017). The article shows that the values of correction factors are very robust and insensitive to most details of the calculations except the values of the underlying electron stopping powers which have a significant effect on the stopping-power ratio and on Kcomp. The 1% uncertainties on the photon cross-sections have a negligible effect on these correction factors except for Kcomp. As a result of these investigations, with no change in the stopping power data used, the Canadian primary standard of air kerma in a 60Co beam needs to be increased by 0.54%.

This paper presents a new category of decision-support tools that builds on today's Geographic Information Systems (GIS) and On-Line Analytical Processing (OLAP) technologies to facilitate Geographic Knowledge Discovery (GKD). This new category, named Spatial OLAP (SOLAP), has been an R&D topic for about 5 years in a few university labs and is now being implemented by early adopters in different fields, including public health where it provides numerous advantages. In this paper, we present an example of a SOLAP application in the field of environmental health: the ICEM-SE project. After having presented this example, we describe the design of this system and explain how it provides fast and easy access to the detailed and aggregated data that are needed for GKD and decision-making in public health. The SOLAP concept is also described and a comparison is made with traditional GIS applications.

The AAMC Curriculum Management & Information Tool (CurrMIT) is a relational database containing curriculum information from medical schools throughout the United States and Canada. CurrMIT can be used to document details of instruction, such as outcome objectives, resources, content, educational methods, assessment methods, and educational sites, which are being employed in curricula. CurrMIT contains basic information about nearly all required courses and clerkships being offered in the United States and Canada. The database contains descriptions of more than 15,000 courses and clerkships; approximately 115,000 "sessions"--e.g., lectures, labs, small-group discussions--and more than 400,000 keywords and word strings documenting the specific details of instruction associated with the courses, clerkships, and sessions. Some specific uses that schools have made of CurrMIT include review of demographics among patient cases being used in a case-based curriculum; comparisons of educational experiences between two geographically separate clinical campuses; and identification of unplanned redundancies and gaps in curricular content. CurrMIT has been designed to accommodate data from virtually any medical school curriculum; "traditional 2+2" curricula, problem-based curricula, and systems-based curricula, and variations of each of these, have been entered in CurrMIT by medical schools. The authors give an overview of the technology upon which the system is built and the training materials and workshops that the AAMC provides to faculty to support CurrMIT's use, and end by describing enhancements being planned for the system.

Objective: To estimate cost savings from emergency contraceptive pills in Canada., Methods: We modeled cost savings when a single emergency contraceptive treatment was provided after unprotected intercourse and when women were provided emergency contraceptive pills in advance., Results: Each dollar spent on a single treatment saved $1.19--$2.35 (in Canadian currency), depending on the regimen and on assumptions about savings from costs avoided by preventing mistimed births. The dedicated products Preven (Shire Canada, Inc., Oakville, Ontario) and Plan B (Paladin Labs, Inc., Montreal) were cost-saving even under the least favorable assumption that mistimed births prevented today occur 2 years later. Each dollar spent on advance provision of Preven saved $1.24--$12.23, depending on the regular contraception method, on how consistently emergency contraception was used when needed, and on whether mistimed births were averted forever or simply delayed. Plan B was almost always cost-saving, although less so., Conclusion: Emergency contraception was cost-saving whether provided when the emergency occurred or in advance to be used as needed. More extensive use of emergency contraception could save considerable medical costs by reducing unintended pregnancies.

The present situation regarding Listeria monocytogenes and ready-to-eat (RTE) seafood is discussed. An updated regulatory policy on L. monocytogenes directs inspection and compliance action to those RTE foods capable of supporting growth of the organism and is based on a combination of inspection, environmental sampling and product testing. The incidence of L. monocytogenes in imported seafood products in 1996-1997 and 1997-1998 was 0.88 and 0.3%, respectively. With respect to domestic products, an analysis of 347 RTE foods in 1997-1998 and 1998-1999, at one of the large fish inspection labs in the Maritimes, revealed an absence of L. monocytogenes. The only seafood product linked to suspect cases of listeriosis in Canada was imported.

The proper teaching of operative skills to surgical residents is increasingly constrained by operative time, complex procedures and medicolegal concerns. A technical-skills program was developed and introduced over a 3-year period to 28 1st-year residents in general surgery. To introduce the residents to the principles of surgical techniques in a simulated environment outside the operating room, the program consisted of a combination of two didactic sessions and six "wet labs" taking 3 to 4 hours per week for 8 weeks between January and March each year. The didactic sessions included instruction on suture material and the use of stapling devices; the "wet lab" used a "hands-on" approach. Educational objectives in the "wet lab" included instruction on preparation of the patient and draping, aseptic technique, principles of bowel anastomosis, incisions, instrument use and handling, principles of hemostasis, intraoperative surgical emergencies, surgical assisting and overall conduct in the operating room. The residents' surgical technique and skills improved over the course period. The overall value, teaching and understanding of surgical principles were rated highly. Problems cited during resident feedback were the use of live animals and insufficient time to practise. The efficacy of a surgical-skills program has been demonstrated, but its effectiveness requires further evaluation.