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Gay, bisexual and other men who have sex with men (gbMSM) were ineligible to donate blood in most countries since the 1980's. In Canada the deferral period has been incrementally decreased from lifetime to male-to-male sex in the last 3 months. Now a few countries have removed the deferral altogether. Risk models have been utilised to estimate the probability of an HIV positive donation being released into the blood supply and to inform incremental changes to the length of the deferral period. Here we use public health data to estimate the risk of HIV if the gbMSM deferral criteria were removed in Canada. We calculate the risk reduction among heterosexuals based on responses to standard risk questions routinely asked of donors. We assume gbMSM will donate at the same rate as heterosexual males. We apply the same risk reduction principle to HIV incidence and prevalence among gbMSM in the general population to evaluate the HIV risk without gbMSM time deferral. We model three scenarios where risk reduction is varied by assumptions about incidence and compliance with deferral criteria. The estimates for all scenarios were not significantly different to the currently observed scenario which predicts a residual risk of 0.02 HIV positive per million donations (95% CI: 0.000006–0.09). The models predict that removing the gbMSM deferral criteria would result in HIV residual risk similar to currently observed. [ABSTRACT FROM AUTHOR]

Abstract: We show convexity of solutions to a class of convex variational problems in the Gauss and in the Wiener space. An important tool in the proof is a representation formula for integral functionals in this infinite dimensional setting, that extends analogous results valid in the classical Euclidean framework. [Copyright &y& Elsevier]

The safety of the blood supply depends on measures to protect not only the transfusion recipient but also the blood donor. Donor selection criteria have been voluntarily adopted or enforced through regulation in different countries, but review of practices in different blood centers reveals wide disparity in the current approaches. Such variability in practice suggests that the criteria for the protection of donor are often arbitrary or reflect deeply engrained precautionary practices and exposes the inherent uncertainty about the best way to minimize risk to the donor. Certain selection criteria introduced years ago have become dogma in some countries but were never subjected to systematic study and persist despite available evidence that the measures do not measurably improve donor safety. Current efforts to define a rational, evidence-based approach are crucial to eliminate practices that lead to the unnecessary deferral of large numbers of blood donors without improving the safety of the donation process. Future prospects to improve the safety of the donation process rest with hemovigilance initiatives to monitor the effectiveness of interventions to minimize the risks to blood donors. © 2009 Elsevier Inc. All rights reserved. [ABSTRACT FROM AUTHOR]

Over the last 20 years, the Canadian Blood Services' (CBS) Donor Health Assessment Questionnaire (DHAQ), used to screen prospective blood donors to determine their eligibility, has grown in complexity and length. Its growth is inextricably linked to the evolution of the environment within which CBS operates from unregulated collection and distribution of labile blood products to a fully regulated environment and to the need to satisfy both Health Canada and US Food and Drug Administration (FDA) requirements. Within this context, the development of the CBS DHAQ has been characterized by addition of questions and items without any periodic reevaluation of the need for retaining existing questions and/or items. In this review, we apply principles from cognitive science relating to how people think when answering questionnaires to the situation of blood donors completing the DHAQ. We show that some items that were added at different times in separate questions, for reasons that were historically relevant, could be now asked more simply with a single question. The historical development of the DHAQ, resulting in the condensing of many items into lists, the use of complex wording, and the sheer number of items included in the questionnaire make accurate retrieval of information from the donor's memory difficult. Thus, we believe that redesigning the DHAQ will improve the quality and accuracy of the donors' answers to screening questions.Copyright © 2007 by Elsevier Inc. [ABSTRACT FROM AUTHOR]

The in vitro response in simulated body fluid (SBF) of silicate glass coatings on Ti6Al4V was evaluated. Glasses belonging to the SiO2–CaO–MgO–Na2O–K2O–P2O5 system were used to prepare 50–70 μm thick coatings on Ti6Al4V, employing a simple enameling technique. Glasses with silica content higher than 55 wt% can be used to prepare coatings that do not crack or delaminate and exhibit good adhesion to the alloy. It has been found that coatings with silica content lower than 60 wt% are more susceptible to corrosion and precipitate carbonated hydroxyapatite on their surface during in vitro tests. However, these coatings have a higher thermal expansion than the metal and are under tension. After 2 months in SBF cracks grow in the coating that reach the glass/metal interface and initiate delamination. Glasses with silica content higher than 60 wt% are more resistant to corrosion and have lower thermal expansion. These coatings do not crack but they do not precipitate apatite even after 2 months in SBF. [Copyright &y& Elsevier]

Little is known about the micronutrient status of Chinese women of childbearing age. We assessed nonfasting plasma concentrations of folic acid, vitamin B-12, vitamin B-6 (as pyridoxal-5'-phosphate), hemoglobin (Hb), ferritin and transferrin receptor (TfR) in 563 nonpregnant textile workers aged 21-34 y from Anqing, China. All women had obtained permission to become pregnant and were participating in a prospective study of pregnancy outcomes. Mean (SD) plasma concentrations were 9.7 (4.1) nmol/L folic acid, 367 (128) pmol/L vitamin B-12, 40.2 (15.8) nmol/L vitamin B-6, 108 (12. 9) g/L Hb, 42.6 (34.2) microgram/L ferritin and 5.2 (2.7) mg/L TfR. Twenty-three percent of women had biochemical evidence of folic acid deficiency, 26% were deficient in vitamin B-6 and 10% had low vitamin B-12. Overall, 44% of women were deficient in at least one B vitamin. Although anemia (Hb < 120 g/L) was detected in 80% of women, only 17% had depleted iron stores (ferritin < 12 microgram/L); 11% had elevated TfR concentrations. Distinct seasonal trends were observed in the prevalence of moderate anemia (Hb < 100 g/L) and deficiencies of folic acid and vitamin B-6, with significantly lower concentrations of folate and Hb occurring in summer and lower concentrations of vitamin B-6 occurring in winter and spring than in other seasons. We conclude that deficiencies of folic acid, vitamin B-6 and iron were relatively common in this sample of Chinese women of childbearing age and were contributing to the high prevalence of anemia. Without appropriate supplementation, these deficiencies could jeopardize the women's health and increase their risk of adverse pregnancy outcomes. [ABSTRACT FROM AUTHOR]

We have adapted an in vitro digestion/Caco-2 cell model to assess Fe availability from foods, by using ferritin formation by Caco-2 cells as an indicator of Fe uptake. Ferritin formation by Caco-2 cells occurs in response to Fe uptake at concentrations of available Fe greater than that of the culture media to which the cells have been adapted. This methodology circumvents the need for using radioactive Fe and thus eliminates the costs and controversies associated with food radiolabeling. To validate this method, we measured ferritin formation in Caco-2 cells exposed to digests containing Fe of relatively high and low availability. Our objective was to determine if ferritin formation would be proportional to Fe uptake and sufficiently sensitive to be an indicator of Fe availability from food digests. Our model uses established in vitro digestion techniques coupled with uptake of Fe by Caco-2 cell monolayers. Measurement of cell ferritin was done by a commercially available RIA. Higher ferritin formation was observed in cells exposed to digests containing FeSO4 plus ascorbic acid vs, digests containing FeSO4 plus citric acid. Additional comparisons of Fe availability from digests of beef, fish, corn and green beans yielded results that demonstrate higher Fe availability (i.e., greater ferritin formation) from beef and fish digests than from digests of corn and green beans. Overall, the results document the promotional effects of ascorbic acid and animal tissue on Fe uptake as measured indirectly by ferritin formation. The results of this study indicate that ferritin formation by Caco-2 cell monolayers is highly sensitive and accurately measures food Fe availability in this in vitro system. [ABSTRACT FROM AUTHOR]

According to Jewish tradition, Mezuzahs should be affixed on all doorposts leading to communal places. We evaluated the bacterial pathogenic load on the Mezuzah covers in our hospital. Mezuzahs were sampled in all hospital departments, and cultures were carried out. Serving as a control group, door handles belonging to the same departments were tested as well. Most samples harbored potential pathogens. Few cultures were positive in the control group, demonstrating that regular disinfection is carried out, but apparently religious artifacts are overlooked. [ABSTRACT FROM AUTHOR]

As a few recent studies failed to show beneficial effect of Positive Airway Pressure (PAP) on the sleep apnea patients with cardiovascular comorbidities, we aimed to use large administrative database to investigate the association of PAP usage and the health economics outcomes of the sleep apnea patients with a new onset of heart failure (HF). We have found a significant association of the PAP usage with higher one-year survival and lower hospital charge among sleep apnea patients with a new onset of heart failure (HF). [Extracted from the article]

The hydrogen permeation behavior of X65 steel was studied in a simulated Canadian groundwater (NS4) using a Devanathan-Stachurski cell. In the absence of a palladium coating on the detection side of the steel membrane, the hydrogen permeation current was suppressed by the growth of an oxide film on the steel. When a palladium coating was applied it was necessary to first remove the air-formed oxide from the steel surface which would otherwise control the permeation behavior due to its low hydrogen diffusivity. On the charging side of the membrane the deposition of CaCO 3 and Mg(OH) 2 enhanced hydrogen absorption into the cell leading to an enhanced permeation current. • The calcareous deposits was confirmed to enhance hydrogen absorption into steel. • The air-formed iron oxides can greatly reduce hydrogen permeation rate. • A model was proposed to interpret the hydrogen permeation rate with oxides present. [ABSTRACT FROM AUTHOR]

Although the DC-based immunotherapy of cancer has been promising in animal models, several questions need to be addressed in depth in humans: the generation of various types of dendritic cells, the analysis of their potential and the immunomonitoring of cancer patients. In our laboratory, our efforts have been focused on (i) the study of the cytotoxic activity of dendritic cells; (ii) the generation of a novel population of human dendritic cells from monocytes cultured in IL-3 and IFN-β; (iii) the optimisation of the immunostimulatory properties of DC using Fas-ligand surexpression or adjuvants promoting DC/γ-δ T cell interaction. [Copyright &y& Elsevier]

Summary: The potential for vaccines to act as triggers of autoimmune reactions has received much recent attention. Such an association is very poorly defined mechanistically, but may potentially involve epitope mimicry between vaccinal and self antigen, or the immuno-stimulatory effects of vaccine adjuvant. If such reactions occur, they are more likely to involve adults than infants in early life, as a reflection of the immunological immaturity of the newborn. There has been a recent focus in immunology on the link between innate and adaptive immunity provided by dendritic cells and the range of Toll-like receptors (TLRs) that are the point of first contact of these cells with microbial antigen. These interactions appear to determine the nature of the subsequent adaptive immune response and whether it may be mediated by Th1, Th2, Th17 or T regulatory populations. TLR interactions may also be significant in the induction of vaccinal immunity and agonists of these receptors are being developed as potential vaccine adjuvants. There are differences in cytokine production of adult and newborn dendritic cells, and these differences must be considered in the application of such novel adjuvants to products intended for either age group. [Copyright &y& Elsevier]