Surveying the local public health response to COVID-19 in Canada: Study protocol.

Background: Public health services and systems research is under-developed in Canada and this is particularly the case with respect to research on local public health unit operational functioning and capacity. The purpose of this paper is to report on a study that will collect retrospective information on the local public health response to COVID-19 throughout Canada between 2020 and 2021.

Methods/design: The goal of the study is to develop and implement a study framework that will collect retrospective information on the local public health system response to the COVID-19 pandemic in Canada.

Cadmium disrupts melanocortin 2 receptor signaling in rainbow trout.

Cadmium is an endocrine disruptor and inhibits corticosteroid production, but the mechanisms are far from clear. We tested the hypothesis that sublethal exposure to environmentally realistic levels of cadmium impairs cortisol production by disrupting the melanocortin 2 receptor (MC2R) signaling in rainbow trout (Oncorhynchus mykiss). Fish were exposed to sublethal concentrations of cadmium (0.

Utility of Transient Elastography in Estimating Hepatic Iron Concentration in Comparison to Magnetic Resonance Imaging in Patients Who are Transfusion-Dependent: A Canadian Center Experience.

Transfusion-dependent hereditary anemias such as β-thalassemia (β-thal), predispose patients to iron overload and its numerous clinical sequelae. Accurate assessment of overall iron status and prompt initiation of chelation therapy to prevent irreversible end-organ damage can be achieved using magnetic resonance imaging (MRI) to measure liver iron concentration (LIC) as a surrogate marker of total body iron; however, its access may be associated with long wait times and delay in treatment. We report an observational cohort study at a single tertiary care center assessing the theoretical role of transient elastography (TE), which measures liver stiffness, in estimating LIC compared to other established diagnostic measures.

Identifying the activation motif in the N-terminal of rainbow trout and zebrafish melanocortin-2 receptor accessory protein 1 (MRAP1) orthologs.

The activation of mammalian melanocortin-2 receptor (MC2R) orthologs is dependent on a four-amino acid activation motif (LDYL/I) located in the N-terminal of mammalian MRAP1 (melanocortin-2 receptor accessory protein). Previous alanine substitution analysis had shown that the Y residue in this motif appears to be the most important for mediating the activation of mammalian MC2R orthologs. Similar, but not identical amino acid motifs were detected in rainbow trout MRAP1 (YDYL) and zebrafish MRAP1 (YDYV).

Structure/function studies on the activation of the rainbow trout melanocortin-2 receptor.

Functional expression of the rainbow trout (rt) melanocortin-2 receptor (MC2R) in CHO cells requires co-expression with a teleost melanocortin-2 receptor accessory protein (MRAP) such as zebrafish (zf) MRAP. Transiently transfected rtMC2R/zfMRAP1 CHO cells were used to evaluate the efficacy of alanine substituted analogs of hACTH(1-24) in three motifs in the ligand: H(6)F(7)R(8)W(9), G(10)K(11)P(12)V(13)G(14), and K(15)K(16)R(17)R(18)P(19). Alanine substitution at all positions in each motif either completely blocked activation of the receptor (H(6)F(7)R(8)W(9) and K(15)K(16)R(17)R(18)P(19)) or resulted in just over 400 fold increase in EC50 value (G(10)K(11)P(12)V(13)G(14)).

Exposure to environmental levels of waterborne cadmium impacts corticosteroidogenic and metabolic capacities, and compromises secondary stressor performance in rainbow trout.

The physiological responses to waterborne cadmium exposure have been well documented; however, few studies have examined animal performances at low exposure concentrations of this metal. We tested the hypothesis that longer-term exposure to low levels of cadmium will compromise the steroidogenic and metabolic capacities, and reduce the cortisol response to a secondary stressor in fish. To test this, juvenile rainbow trout (Oncorhynchus mykiss) were exposed to 0 (control), 0.

Cadmium-mediated disruption of cortisol biosynthesis involves suppression of corticosteroidogenic genes in rainbow trout.

Cadmium is widely distributed in the aquatic environment and is toxic to fish even at sublethal concentrations. This metal is an endocrine disruptor, and one well established role in teleosts is the suppression of adrenocorticotrophic hormone (ACTH)-stimulated cortisol biosynthesis by the interrenal tissue. However the mechanism(s) leading to this steroid suppression is poorly understood.