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Reactions of nickel boranyl compounds with pnictogen–carbon triple bonds
No full textThe catalytic conversion of unsaturated small molecules such as nitriles into reduced products is of interest for the production of fine chemicals. In this vein, metal–ligand cooperativity has been leveraged to promote such reactivity, often conferring stability to bound substrate – a balancing act that may offer activation at the cost of turnover efficiency. This report describes the reactivity of a [(diphosphine)Ni] compound with pnictogen carbon triple bonds (R–C[triple bond, length as m-dash]E; E = N, P), where the diphosphine contains two pendant borane groups. For E = N, cooperative nitrile coordination is observed to afford {Ni}2 complexes displaying B–N interactions, whereas for E = P, B–P interactions are absent. This work additionally outlines a structure–activity relationship that uses nitrile dihydroboration as a model reaction to unveil the effect of SCS stabilization, employing [(diphosphine)Ni] where the diphosphine contains 0, 1, or 2 pendant Lewis acid groups
Introducing canine lifestyle medicine and access to care in context of an interprofessional framework
No full textEvolution of the One Health research portfolio at Western University of Health Sciences (WesternU) aligns with our renowned interprofessional practice and education program that emphasizes team building, communication, ethics, roles and responsibilities. Our college strives to serve the community through clinical services and student-centered research
Recurring Trans-Atlantic incursion of clade 2.3.4.4b H5N1 viruses by long distance migratory birds from Northern Europe to Canada in 2022/2023
No full textIn December 2022 and January 2023, we isolated clade 2.3.4.4b H5N1 high-pathogenicity avian influenza (HPAI) viruses from six American crows (Corvus brachyrhynchos) from Prince Edward Island and a red fox (Vulpes vulpes) from Newfoundland, Canada. Using full-genome sequencing and phylogenetic analysis, these viruses were found to fall into two distinct phylogenetic clusters: one group containing H5N1 viruses that had been circulating in North and South America since late 2021, and the other one containing European H5N1 viruses reported in late 2022. The transatlantic re-introduction for the second time by pelagic/Icelandic bird migration via the same route used during the 2021 incursion of Eurasian origin H5N1 viruses into North America demonstrates that migratory birds continue to be the driving force for transcontinental dissemination of the virus. This new detection further demonstrates the continual long-term threat of H5N1 viruses for poultry and mammals and the subsequent impact on various wild bird populations wherever these viruses emerge. The continual emergence of clade 2.3.4.4b H5Nx viruses requires vigilant surveillance in wild birds, particularly in areas of the Americas, which lie within the migratory corridors for long-distance migratory birds originating from Europe and Asia. Although H5Nx viruses have been detected at higher rates in North America since 2021, a bidirectional flow of H5Nx genes of American origin viruses to Europe has never been reported. In the future, coordinated and systematic surveillance programs for HPAI viruses need to be launched between European and North American agencies.Canadian Food Inspection Agency emergency funding for the 2022 outbreak (YB)Department for Environment, Food and Rural Affairs (Defra, UK)Devolved Administrations of Scotland and Wale
Differentiation of stable kidney function versus progressive dysfunction in dogs
No full textBackground
Circulating creatinine and symmetric dimethylarginine (SDMA) are biomarkers of kidney function that have been used variously to define stable vs progressive chronic kidney disease (CKD). Slope monitoring of inverse biomarker values (creatinine−1 or SDMA−1) has shown promise, but quantitative criteria to distinguish stable vs progressive CKD using this approach are lacking.
Objective
Assessment of creatinine−1 and SDMA−1 slope cutoffs to distinguish stable vs progressive CKD.
Animals
One hundred ten clinically healthy university staff-owned dogs and 29 male colony dogs with progressive X-linked hereditary nephropathy (XLHN).
Methods
Retrospective analysis combining 2 prospective observational studies, 1 tracking kidney function biomarkers in healthy dogs (HDs) to a maximum of 3 years, and 1 tracking kidney function biomarkers in male colony dogs with progressive XLHN to a maximum of 1 year. The minimum slope of creatinine−1 or SDMA−1 as measured using the IDEXX SDMA test from HD was assigned as the slope cutoff for stable kidney function.
Results
The stable vs progressive slope cutoff was −0.0119 week × dL/mg for creatinine−1 and −0.0007 week × dL/μg for SDMA−1
The effect of berry consumption on oxidative stress Biomarkers: A systematic review of randomized controlled trials in humans
No full textBioactive compounds in berries may scavenge reactive oxygen and nitrogen species by donating electrons to free radicals, thereby protecting DNA, proteins, and lipids from oxidative damage. Evidence shows that berry consumption has beneficial health effects, though it remains unclear whether berries exert a significant impact on oxidative stress in humans. Thus, we performed a systematic review of randomized controlled trials (RCT) to examine the effects of non-acute (more than a single dose and ≥7 days) berry consumption on biomarkers of oxidative stress. Searches were conducted in PubMed, Cochrane Library, and Scopus; results were imported into Covidence for screening and data extraction. The literature search identified 622 studies that were screened, and 131 full-text studies assessed for eligibility. Ultimately, 28 RCTs met the eligibility criteria. Common biomarkers of oxidative stress (antioxidants, DNA damage, isoprostanes, malondialdehyde, and oxidized LDL) were systematically reviewed, and results were reported narratively. Of the approximate 56 oxidative stress biomarkers evaluated in the 28 RCTs, 32% of the biomarkers were reported to have statistically significant beneficial results and 68% of the biomarkers were reported as having no statistically significant differences. More well-designed and longer-term berry RCTs are needed to evaluate biomarkers of oxidative stress
Neurosteroids and the mesocorticolimbic system
No full textThe mesocorticolimbic system coordinates executive functions, such as working memory and behavioral flexibility. This circuit includes dopaminergic projections from the ventral tegmental area to the nucleus accumbens and medial prefrontal cortex. In this review, we summarize evidence that cells in multiple nodes of the mesocorticolimbic system produce neurosteroids (steroids synthesized in the nervous system) and express steroid receptors. Here, we focus on neuroandrogens (androgens synthesized in the nervous system), neuroestrogens (estrogens synthesized in the nervous system), and androgen and estrogen receptors. We also summarize how (neuro)androgens and (neuro)estrogens affect dopamine signaling in the mesocorticolimbic system and regulate executive functions. Taken together, the data suggest that steroids produced in the gonads and locally in the brain modulate higher-order cognition and executive functions.Natural Sciences and Engineering Research Council of Canada (NSERC)Canadian Institutes of Health Research (CIHR
Impact on canine neutrophil preservation with the addition of bovine serum albumin to K 3 ‐EDTA whole blood samples
No full textBackground
Cellular deterioration occurs with blood sample aging, impacting white blood cell (WBC) identification and differential accuracy. This may be exacerbated in samples from patients experiencing inflammation. Previously, bovine serum albumin (BSA) has been shown to improve cellular preservation of blood and other samples, but the effect on cell preservation in canine blood has not been assessed.
Objectives
We aimed to determine the effects of BSA on neutrophil nuclear area when added to potassium ethylene diamine tetra-acetic acid (K3-EDTA)-anticoagulated canine blood prior to blood smear preparation. We evaluated the impact of inflammatory leukograms, sample storage temperatures (4° and 20°C), and time on outcomes.
Materials and methods
Canine K3-EDTA-anticoagulated blood samples stored at 4° and 20°C were used from unique patients, 10 with and 10 without inflammatory leukograms. Blood smears were prepared from aliquots with or without the addition of 22% BSA at 0, 4, 8, 24, 48, and 72 h. The nuclear area was measured for 25 randomly selected neutrophils per slide using Fiji software. Mixed-effect linear regression modeling was performed (significance: P < 0.05).
Results
Nuclear area increased over time with and without added BSA. Both sample storage temperatures and the presence or absence of an inflammatory leukogram significantly impacted neutrophil nuclear area. Samples with added BSA had slightly higher predicted nuclear areas than those without BSA, but this difference was not statistically significant.
Conclusions
BSA did not significantly impact neutrophil nuclear area and did not improve neutrophil preservation in canine blood samples.Companion Animal Trust Fund at the University of Prince Edward Islan
Rejection of Lepeophtheirus salmonis driven in part by chitin sensing is not impacted by seawater acclimitization in Coho salmon (Oncorhynchus kisutch)
No full textThere is tremendous variation in life-history strategies among anadromous salmonids. Species that enter the ocean environment at small sizes ( 90% of all parasites lost by 16 days post-infection (dpi). Rejection was concomitant with host epithelial granulomatous infiltrations that initially targeted the embedded frontal filament (4 dpi) and the entire parasite by 10 dpi. Illumina sequencing, followed by functional enrichment analysis, revealed a concerted defense response in the fin within 1 dpi that included multiple innate and adaptive immunity components. Strikingly, early indications of an allergic-type inflammatory response were associated with chitin sensing pathways orchestrated by early overexpression of the IgE-receptor, fcer1g. Additionally, there was profound overexpression of several classes of c-type lectin receptors, including dectin-2, mincle, and dc-sign at 1 dpi onward. These profiles and upregulation of cellular effector markers were corroborated by histopathological evaluation, revealing the simultaneous presence of mast cell/eosinophilic granular cells, sacciform cells, macrophages/histiocytes, and granulocytes in fin. At 10 dpi and concurrent with parasite expulsion, there was evidence of immunoregulation in addition to tissue remodelling pathways. At 16 dpi, the response was effectively abrogated. Simultaneous profiling of the parasite transcriptome revealed early induction of chitin metabolism and immunomodulation, toxin production and ECM degradation; however, after 7 dpi, these were replaced with overexpression of stress and immune defense genes. These data present the first evidence for Coho salmon demonstrating chitin- and sugar moiety-sensing as key drivers of salmon louse rejection.Fisheries and Oceans CanadaElanco Animal Health CanadaMDF NSERC DiscoveryACOA-AIF (TREAT2
Bovine Viral Diarrhea Virus (BVDV) vaccine usage in Atlantic Canada and the evaluation of a novel method to detect BVDV persistently infected individuals by swabbing consumption surfaces
No full textThe overall research goal was to evaluate control methods for bovine viral diarrhea virus (BVDV) in dairy cattle within Atlantic Canada (AC). This took the form of two primary objectives: 1) BVDV vaccine use assessment; and 2) evaluation of the prevalence and two screening methods for BVDV persistently infected (PI) individuals. To assess BVDV vaccine use in the four AC provinces, questionnaires were sent to all registered dairy herds within AC (n=647). Serial bulk tank milk (BTM) samples were collected from those herds and evaluated with enzyme-linked immunosorbant assay (ELISA) for antibody and with reverse-transcriptase polymerase chain reaction (RT-PCR) to compare these results by vaccine group. BVDV vaccinated herds comprised 167 of 246 respondents (67.9%). Of these vaccinated herds, 89.2% used “modified-live virus” (MLV) vaccine and 46.7% used “killed virus” (KV) vaccine, at some level in the herd. A combination of MLV and KV vaccine use was seen in 35.9% of herds. In respondent vaccinated herds within the region as a whole, 37.1% were vaccinated once annually, while 62.9% vaccinated at multiple times throughout the year. A total of 5 herds had a positive PCR on BTM and 8 were suspect-PCR-positive. The average sample-to-positive (S/P) ratio of unvaccinated herds was 0.402, but over 0.653 in vaccinated herds, depending on the vaccine type used. Although vaccine use was common, there is room for improvement, and given that there were BVDV RT-PCR-positive BTM tests among
vaccinated herds, a multimodal approach to BVD control should be taken. The second objective involved screening for and identifying PI animals throughout the AC provinces of Nova Scotia, New Brunswick, and Prince Edward Island. To identify PI individuals, all registered dairy herds in the region had BTM screening with antibody ELISA and RT-PCR. This was followed by whole herd animal testing of milk, serum or tissue by antigen ELISA among herds considered likely to have a PI animal on BTM results. From the antigen ELISA date, 8 herds had a PI identified, for a herd level PI true prevalence of 1.38%. A novel screening method using a consumption surface swab assay (CSSA- using RT-PCR tests of 6 swabs of feed bunk/waterer surfaces per farm) was evaluated against the antigen ELISA data in 59 herds, and compared to another screening method, sentinel animal monitoring (SAM) in 44 herds (using
antibody ELISA tests of 6 unvaccinated animals per farm). In our study, the sensitivity of SAM was 83.3%, while specificity was 81.6%. The CSSA demonstrated a sensitivity of 50%, while specificity was 100%. Three herds that contained a PI animal and had a positive CSSA were swabbed in groups with 20 animals. The CSSA, as used in our study, may be utilized as a confirmatory test but not a screening test at present. Future research should explore swabbing protocols with PI animals in different group sizes to enhance test sensitivity
