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Background: Cardiac Implantable Electronic Devices (CIED) include pulse generators and leads. In some implanting centers, it is a common practice to combine devices with leads from different companies. Case series have reported episodic high‐impedance changes in Boston Scientific CIEDs with competitor leads. We investigated the incidence of high‐impedance abnormalities in matched versus mismatched Boston Scientific Accolade pacemakers. Methods: A retrospective chart review identified all consecutive Boston Scientific Accolade pacemakers implanted between January 2017 and June 2019 at a Canadian tertiary care center. The primary outcome was the occurrence of transient, high‐impedance changes which resulted in a switch to unipolar pacing/sensing in the absence of any other identifiable lead issue. Fisher exact tests (two‐tailed, α =.05) were used to compare the incidence of outcomes in matched versus mismatched systems. Results: 514 Boston Scientific Accolade pacemakers were associated with 882 individual leads. The primary outcome occurred with 21 leads (20 Medtronic and 1 Abbott), associated with occasional pacing inhibition, presyncope, and/or early surgical revision. Mismatched lead‐device pairs were significantly associated with CIED malfunction compared to matched lead‐device pairs (3.3% vs. 0%, p =.0019). The median time from implant to unipolar safety switch was 12.4 months. The median follow‐up time was 21.6 months. Conclusion: Use of mismatched leads with a Boston Scientific Accolade device was associated with an increased risk of undesirable changes in sensing polarity with occasional inappropriate pacing inhibition. Awareness of this interaction can allow for the institution of appropriate programming remedies and may increase scrutiny of the use of mismatched CIED systems. [ABSTRACT FROM AUTHOR]

Vitamin B6 is important in fetal development, but little is known of the vitamin B6 status of pregnant women and newborns in North America and potential modifying factors. This prospective study determined maternal and cord plasma concentrations of pyridoxal 5′ phosphate (PLP; an indicator of vitamin B6 status) in a convenience sample of 368 Canadian pregnant women and their newborns. The association of maternal intake of vitamin B6 and fetal genetic variants with cord plasma PLP and homocysteine concentrations was also examined. Dietary and supplemental intakes of vitamin B6 were assessed in early and mid to late pregnancy. PLP concentrations were measured in maternal plasma in early pregnancy and at delivery, and in cord plasma. Six fetal variants of the MTHFR and CβS genes were assessed for their association with cord plasma PLP and homocysteine concentrations. Geometric mean (95% CI) PLP concentrations were 107 (98, 116) nmol/L in early pregnancy and 58 (53, 62) nmol/L at delivery, respectively, and 296 (275, 319) nmol/L in cord blood ( p < .0001). During early pregnancy and at delivery, 3.6% and 5.5% of women had plasma PLP concentrations <20 nmol/L, respectively. Ninety eight percent of the women with supplemental B6 intake of at least the recommended dietary allowance had PLP concentrations >20 nmol/L. Fetal genetic variants were not associated with cord PLP and homocysteine concentrations. Vitamin B6 deficiency is uncommon in a cohort of Canadian pregnant women due largely to prevalent vitamin B6 supplement use. [ABSTRACT FROM AUTHOR]

The article presents the study that explores on the use of haematopoietic stem cell transplantation (SCT) in the treatment of Fanconi anemia (FA) patients in Canada and the U.S. The topics discussed include the attributes of FA, the factors that influenced the decision making of FA patients and family members on SCT, and the benefits and probable risks of SCT.

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Estimating number of prey killed by carnivores such as wolves (Canis lupus) per unit time, or kill rate, is important for the conservation and management of carnivores and their prey. We reviewed published methods to estimate wolf kill rates and found them inconsistent and lacking a basis in statistical sampling theory. We developed a general statistical estimator for kill rate and variance using ratio-variable sampling theory. We illustrate our ratio estimator by estimating wolf kill rates in a multiple-prey system in Banff National Park, Alberta, for winters from 1986 to 2000. We used snow tracking and radiotelemetry to locate 429 kills during 195 sampling intervals covering 1,294 days. Mean kill rate by wolf packs (expressed as the number of kills/day/pack, k/d/p) was 0.33 k/d/p, most of which, 0.23 k/d/p, were elk (Cervus elaphus), the most abundant ungulate. Kill-rate estimates were variable despite intensive sampling effort. The mean kill rate of 0.33 k/d/p had a pooled 95% confidence interval of 0.29 to 0.37. An intensive sampling effort of ≥6-8 individual sampling intervals covering approximately 25% of the winter was required to minimize sampling variation. We compared our method to 3 other published methods for estimating kill rates and examined the bias and precision of kill-rate methods using simulations. Our ratio estimator approach was the least biased and most precise when compared to other approaches. Ratio estimators provide a standardized method to estimate kill rates in other predator-prey systems and will facilitate comparison across studies and examination of patterns of kill-rate variation. [ABSTRACT FROM AUTHOR]

(1) Species establishment after 3 years on artificially revegetated ski-slopes of Whistler Mountain, British Columbia, Canada and the nature of species associations were investigated in relation to altitude, slope angle and soil properties. (2) The overall establishment of seeded species from the grass-legume mixture had been satisfactory. (3) Three of the seeded species Fessuca rubra L. Phleum pratense L. and Trifolium hybridum L. had cover values greater than their relative abundance in the seed mixture, whereas the remaining seeded species, A grostis alba L. A. tenuis (Sibth.), Poa compressa L. and Trifolium repens L. were under-represented in the sward. (4) Analysis of variance was used to detect significant variations in the relative abundance of the four most abundant species in relation to altitude and slope angle. In productive habitats F. rubra and T. hybridum attained large cover values and constrained the establishment of the slower growing species, A. tenuis and P. pratense. The latter species were more abundant in resource-poor sites where competition from the productive species was reduced. (5) The vigorous, rhizomatous growth of F. rubra contributed to its dominance in the sward; its positive associations with P. pratense, detected by contact sampling and association analysis, were likely a result of differential rooting strategies. (6) The tussock habit of both A. tenuis and P. pratense restricted their co-habitation in productive sites where competition from F. rubra and T. hybridum is suggested to be most intense. [ABSTRACT FROM AUTHOR]

Deals with a study which determined presented evidence of the relationship between demand for money and macroeconomic variables in Canada. Review of related studies; Employment of the nested hypothesis testing; Discussion of the results.