Normative Peak Cardiopulmonary Exercise Test Responses in Canadian Adults Aged ≥40 Years.

BACKGROUND: Up-to-date normative reference sets for cardiopulmonary exercise testing (CPET) are important to aid in the accurate interpretation of CPET in clinical or research settings. RESEARCH QUESTION: This study aimed to (1) develop and externally validate a contemporary reference set for peak CPET responses in Canadian adults identified with population-based sampling; and (2) evaluate previously recommended reference equations for predicting peak CPET responses. STUDY DESIGN AND METHODS: Participants were healthy adults who were ≥40 years old from the Canadian Cohort Obstructive Lung Disease who completed an incremental cycle CPET. Prediction models for peak CPET responses were estimated from readily available participant characteristics (age, sex, height, body mass) with the use of quantile regression. External validation was performed with a second convenience sample of healthy adults. Peak CPET parameters that were measured and predicted in the validation cohort were assessed for equivalence (two one-sided tests of equivalence for paired-samples and level of agreement (Bland-Altman analyses). Two one-sided tests of equivalence for paired samples assessed differences between responses in the derivation cohort using previously recommended reference equations. RESULTS: Normative reference ranges (5th-95th percentiles) for 28 peak CPET parameters and prediction models for 8 peak CPET parameters were based on 173 participants (47% male) who were 64 ± 10 years old. In the validation cohort (n = 84), peak CPET responses that were predicted with the newly generated models were equivalent to the measured values. Peak cardiac parameters predicted by the previously recommended reference equations by Jones and colleagues and Hansen and colleagues were significantly higher. INTERPRETATION: This study provides reference ranges and prediction models for peak cardiac, ventilatory, operating lung volume, gas exchange, and symptom responses to incremental CPET and presents the most comprehensive reference set to date in Canadian adults who were ≥40 years old to be identified with population-based sampling.

Leprosy in Nonimmigrant Canadian Man without Travel outside North America, 2014.

In Canada, Hansen disease (leprosy) is rare and not considered in diagnoses for nonimmigrant patients. We report Mycobacterium leprae infection in a Canadian man whose sole travel was to Florida, USA. The M. leprae isolate was identified as armadillo-associated genotype 3I-2-v1. Travelers to the southern United States should avoid contact with armadillos.

Canada's neglected tropical disease research network: who's in the core-who's on the periphery?

BACKGROUND: This study designed and applied accessible yet systematic methods to generate baseline information about the patterns and structure of Canada's neglected tropical disease (NTD) research network; a network that, until recently, was formed and functioned on the periphery of strategic Canadian research funding. METHODOLOGY: MULTIPLE METHODS WERE USED TO CONDUCT THIS STUDY, INCLUDING: (1) a systematic bibliometric procedure to capture archival NTD publications and co-authorship data; (2) a country-level "core-periphery" network analysis to measure and map the structure of Canada's NTD co-authorship network including its size, density, cliques, and centralization; and (3) a statistical analysis to test the correlation between the position of countries in Canada's NTD network ("k-core measure") and the quantity and quality of research produced. PRINCIPAL FINDINGS: Over the past sixty years (1950-2010), Canadian researchers have contributed to 1,079 NTD publications, specializing in Leishmania, African sleeping sickness, and leprosy. Of this work, 70% of all first authors and co-authors (n = 4,145) have been Canadian. Since the 1990s, however, a network of international co-authorship activity has been emerging, with representation of researchers from 62 different countries; largely researchers from OECD countries (e.g. United States and United Kingdom) and some non-OECD countries (e.g. Brazil and Iran). Canada has a core-periphery NTD international research structure, with a densely connected group of OECD countries and some African nations, such as Uganda and Kenya. Sitting predominantly on the periphery of this research network is a cluster of 16 non-OECD nations that fall within the lowest GDP percentile of the network. CONCLUSION/SIGNIFICANCE: The publication specialties, composition, and position of NTD researchers within Canada's NTD country network provide evidence that while Canadian researchers currently remain the overall gatekeepers of the NTD research they generate; there is opportunity to leverage existing research collaborations and help advance regions and NTD areas that are currently under-developed.

Sequence-based analysis of the microbial composition of water kefir from multiple sources.

Water kefir is a water-sucrose-based beverage, fermented by a symbiosis of bacteria and yeast to produce a final product that is lightly carbonated, acidic and that has a low alcohol percentage. The microorganisms present in water kefir are introduced via water kefir grains, which consist of a polysaccharide matrix in which the microorganisms are embedded. We aimed to provide a comprehensive sequencing-based analysis of the bacterial population of water kefir beverages and grains, while providing an initial insight into the corresponding fungal population. To facilitate this objective, four water kefirs were sourced from the UK, Canada and the United States. Culture-independent, high-throughput, sequencing-based analyses revealed that the bacterial fraction of each water kefir and grain was dominated by Zymomonas, an ethanol-producing bacterium, which has not previously been detected at such a scale. The other genera detected were representatives of the lactic acid bacteria and acetic acid bacteria. Our analysis of the fungal component established that it was comprised of the genera Dekkera, Hanseniaspora, Saccharomyces, Zygosaccharomyces, Torulaspora and Lachancea. This information will assist in the ultimate identification of the microorganisms responsible for the potentially health-promoting attributes of these beverages.

Comparison of patients hemodialyzed for lithium poisoning and those for whom dialysis was recommended by PCC but not done: what lesson can we learn?

AIMS: To compare patients for whom hemodialysis was done for lithium poisoning and those for whom it was recommended by the poison control centre (PCC) but not done and to evaluate the effect of withholding hemodialysis on outcomes. METHODS: All lithium overdoses brought to the attention of the PCC were prospectively followed from January 1 to December 31, 1996. Patients for whom hemodialysis was done were compared with those for whom it was recommended but not done in terms of clinical presentation, lithium elimination half-life, need for transfer to another centre for hemodialysis, and outcome (death, or sequel or recovery). RESULTS: A total of 205 cases of lithium overdoses were collected including 110 with levels higher than 1.5 mmol/l. There were 12 acute lithium overdoses; no patients required hemodialysis and there were no sequel or deaths. There were 174 acute on chronic overdoses; hemodialysis was recommended in 9 patients but only 6 underwent hemodialysis; one patient died during hemodialysis but no other had sequel. There were 19 chronic poisonings; hemodialysis was recommended in 9 patients but only 2 had hemodialysis, a third patient underwent hemodialysis despite it not being recommended; one patient died without hemodialysis and one other had sequel after hemodialysis. No difference were observed between the groups for age, sex, type of poisoning (acute on chronic/chronic), levels (initial/peak/6 hours/extrapolated at 30 hours), time of presentation post-ingestion, presence of co-ingestants, symptoms and signs, Hansen and Amdisen grade, initial creatinine, time of recommendation to perform hemodialysis (daytime or nighttime), need to transfer patients to another centre to perform hemodialysis, and outcome. Patients with acute on chronic poisoning that were not hemodialyzed had longer elimination half-life than those for whom hemodialysis was done even before hemodialysis was performed: 50.1 +/- 13.6 h (n = 3) versus 12.9 +/-12.1 (n = 3) (p = 0.007), respectively. CONCLUSION: No difference was observed between patients for whom hemodialysis was done and those for whom it was recommended by PCC but not done. Despite the death of one patient clearly associated with voluntary withholding hemodialysis, sequel was not seen in that group. The indications for hemodialysis in lithium poisoning should be reconsidered to include only the more severe cases.

Osler and the skin.

William Osler was the greatest physician of his time. Specialists reading his textbooks agreed that in their own specialities he was accurate and illuminating. His grasp of dermatology was particularly striking and skin changes are prominent in five of the syndromes named after him and in at least 100 of his papers. This paper describes how his early training in dermatology under Tilbury Fox in London and Hebra in Vienna combined with his unusual personal qualities to enable him to make massive contributions to a wide variety of dermatological topics. These include smallpox, cutaneous tuberculosis, nail growth, leprosy, scleroderma, pigmentation and purpuric eruptions as well as the more obvious hereditary haemorrhagic telangiectasia, angio-neurotic oedema and Osler's nodes.

Imported diseases: an assessment of trends.

Increasing travel, migration and other forms of international exchange have given a new importance to imported diseases in Canada. This is reflected in the maintenance of an immigration medical screening program, the development of specialized clinics in major cities, increasing interest in tropical medicine and international health, and the designation of a national reference centre for parasitology.The introduction of a point system for immigration selection in 1967 gave rise to a burgeoning influx of people from developing countries that may have plateaued only within the past year. While tuberculosis is probably the single most important health problem in immigration, parasitic infections are of increasing concern. The popularity of overseas travel among Canadians is now also a major factor in the introduction of exotic diseases into Canada. Importation of disease by international trade is far less common than by travel and immigration.On a community health scale a system of monitoring trends of immigration to Canada and travel of Canadians to and from countries with a known risk would likely provide the best indicator of trends in disease importation. Thus, there was an increase of almost threefold (11.6% to 31.1%) between 1965 and 1975 in the proportion of immigration to Canada from countries with a malaria risk and a 2.78-fold increase between 1967 and 1974 in the overall amount of Canadian travel to such countries from which statistics were available.