Publications by authors named "Doherty-Kirby A"

Introduction: Children and youth with disabilities and special healthcare needs, and their families, have been uniquely affected by the COVID-19 pandemic. However, the voices of children themselves are still not well represented in the existing literature.

Methods: This qualitative descriptive study used a combination of visual methods and interviews to learn about the experiences of Canadian children with disabilities (n=18) and their parents (n=14) during the COVID pandemic and into the post-pandemic period.

View Article and Find Full Text PDF

Background: Authentic researcher-youth partnerships in patient-oriented research (POR) where the research responds to the needs expressed by youth themselves are essential to make research meaningful. While patient-oriented research (POR) is increasingly practiced, few training programs exist in Canada and none, to our knowledge, are tailored for youth with neurodevelopmental disabilities (NDD). Our primary objective was to explore the training needs of youth (ages 18-25) with NDD to enhance their knowledge, confidence, and skills as research partners.

View Article and Find Full Text PDF

Background: The global spread of COVID-19 created an explosion in rapid tests with results in < 1 hour, but their relative performance characteristics are not fully understood yet. Our aim was to determine the most sensitive and specific rapid test for the diagnosis of SARS-CoV-2.

Methods: Design: Rapid review and diagnostic test accuracy network meta-analysis (DTA-NMA).

View Article and Find Full Text PDF

Background: Motor proteins from the kinesin-5 subfamily play an essential role in spindle assembly during cell division of most organisms. These motors crosslink and slide microtubules in the spindle. Kinesin-5 motors are phosphorylated at a conserved site by Cyclin-dependent kinase 1 (Cdk1) during mitosis.

View Article and Find Full Text PDF
Article Synopsis
  • Bovine surfactant proteins B (SP-B) and C (SP-C) were analyzed using nano-electrospray ionization mass spectrometry, revealing discrepancies in their molecular masses compared to published data.
  • To clarify the amino acid sequences, SP-B was digested with trypsin for analysis, while SP-C was analyzed in its intact form, leading to the identification of SP-B's sequence with seven cysteine residues.
  • The correction of SP-B's sequence shows it is nearly identical to sheep SP-B, and both proteins feature conserved cysteine residues which are crucial for their biological functions.
View Article and Find Full Text PDF

Exposing BLES (bovine lipid extract surfactant), a clinical surfactant, to reactive oxygen species (ROS) alters surfactant protein B (SP-B), as indicated by Coomassie Blue staining, silver staining, and Western analysis. Hypochlorous acid (HOCl) treatment leads to elevated maximum surface tension (gammamax) and a deterioration in minimum gamma (gammamin) during surface area cycling. Fenton reaction resulted in immediate increases in gammamin and gammamax.

View Article and Find Full Text PDF

A two-dimensional gel electrophoresis (2-DE)-based proteomic approach was used to study a transgenic mouse model of acerbated dilated cardiomyopathy in which the small monomeric GTPase, Rac1, was constitutively expressed exclusively in the myocardium. A subfractionation procedure allowed for the focused analysis of both cytoplasmic and myofilament protein-enriched extracts of ventricular tissue from Rac1 transgenic and age-matched nontransgenic (NTG) mice. The majority of these mice displayed severe hypertrophy (heart-to-body weight ratios >2-fold greater in the Rac1 mice) and died from overt heart failure between days 14 and 17.

View Article and Find Full Text PDF

Osteopontin (OPN) is a highly modified protein that is found in many tissues and has been associated with a variety of physiological and pathological processes. Bone OPN is a potent inhibitor of hydroxyapatite crystal formation and stimulates bone resorption by osteoclasts; these activities, as well as others, are dependent upon phosphorylation of the protein. We have used mass spectrometry (MS) to perform a comprehensive analysis of the post-translational modification of OPN purified from rat bone.

View Article and Find Full Text PDF

CKIP-1 is a pleckstrin homology domain-containing protein that interacts with protein kinase CK2. To elucidate the functions of CKIP-1, we generated human osteosarcoma cell lines with tetracycline-regulated expression of Flag-CKIP-1. Flag-CKIP-1 expression resulted in distinct changes in cellular morphology.

View Article and Find Full Text PDF

Choline acetyltransferase (ChAT) catalyzes the transfer of an acetyl group from acetyl-CoA to choline to produce the neurotransmitter acetylcholine (ACh). We have produced large quantities of pure human ChAT using two different bacterial expression systems. In the first, ChAT is fused to a chitin-binding domain via a self-cleavable linker allowing the release of ChAT without the use of proteases.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates the kinetics of acid-induced denaturation of ferrihemoglobin using electrospray ionization mass spectrometry coupled with online rapid mixing techniques.
  • It identifies different hemoglobin species in solution, including intact tetramers, dimers, monomers, and larger complexes, suggesting they could form weak assemblies in solution.
  • The analysis reveals two populations of tetrameric hemoglobin that disassemble at different rates, with higher-charge state tetramers dissociating quickly to form dimer and globin components, while a slower population disassembles into monomers, indicating a complex unfolding process, particularly for the beta subunit.
View Article and Find Full Text PDF

Choline acetyltransferase (ChAT) synthesizes acetylcholine in cholinergic neurons; regulation of its activity or response to physiological stimuli is poorly understood. We show that ChAT is differentially phosphorylated by protein kinase C (PKC) isoforms on four serines (Ser-440, Ser-346, Ser-347, and Ser-476) and one threonine (Thr-255). This phosphorylation is hierarchical, with phosphorylation at Ser-476 required for phosphorylation at other serines.

View Article and Find Full Text PDF

Cationic peanut peroxidase (CP) was isolated from peanut (Arachis hypogaea) cell suspension culture medium. CP is a glycoprotein with three N-linked glycan sites at Asn60, Asn144, and Asn185. ESI-MS of the intact purified protein reveals the microheterogeneity of the glycans.

View Article and Find Full Text PDF

Molecular determinants underlying the production of siderophores in the human and animal pathogen Staphylococcus aureus and the contribution of siderophore production to the virulence of this bacterium have, until now, remained undefined. Here, we show that S. aureus strains RN6390 and Newman produce siderophore when the cells are starved for iron.

View Article and Find Full Text PDF

Here, we demonstrate the application of the proteomic approach to the study of a transgenic mouse model of heart failure and provide an example of a disease-associated protein alteration that can be observed using this approach. Specifically, we applied the proteomic approach to the analysis of a mouse model of dilated cardiomyopathy in which the small GTPase, Rac1, was constitutively expressed specifically in the myocardium. We utilized the methods of two-dimensional gel electrophoresis (2-DE) for protein separation, silver-staining for protein visualization and mass spectrometry (MALDI-TOF and MS/MS) for protein spot identification.

View Article and Find Full Text PDF

A number of different approaches have been described to identify proteins from tandem mass spectrometry (MS/MS) data. The most common approaches rely on the available databases to match experimental MS/MS data. These methods suffer from several drawbacks and cannot be used for the identification of proteins from unknown genomes.

View Article and Find Full Text PDF

Structural proteomics projects are generating three-dimensional structures of novel, uncharacterized proteins at an increasing rate. However, structure alone is often insufficient to deduce the specific biochemical function of a protein. Here we determined the function for a protein using a strategy that integrates structural and bioinformatics data with parallel experimental screening for enzymatic activity.

View Article and Find Full Text PDF

Casein kinase-2 (CK2) is a pleiotropic and constitutively active serine/threonine protein kinase composed of two catalytic (alpha and/or alpha') and two regulatory beta-subunits, whose regulation is still not well understood. In the present study, we show that the catalytic subunits of human CK2, but not the regulatory beta-subunits, are readily phosphorylated by the Src family protein tyrosine kinases Lyn and c-Fgr to a stoichiometry approaching 2 mol phosphotyrosine/mol CK2alpha with a concomitant 3-fold increase in catalytic activity. We also show that endogenous CK2alpha becomes tyrosine-phosphorylated in pervanadate-treated Jurkat cells.

View Article and Find Full Text PDF
Article Synopsis
  • - Antifreeze proteins in winter rye, similar to two types of chitinases, help the plant acclimate to cold temperatures by potentially binding to ice without significant amino acid modifications.
  • - Researchers isolated cDNAs for two chitinases (CHT9 and CHT46) and found that their mature products were effective in modifying ice growth, confirming these proteins' cold-responsive roles.
  • - The presence of homologous genes in hexaploid wheat suggests that these cold-responsive chitinases may have evolved through gene duplication in winter rye and related cereals.
View Article and Find Full Text PDF

In searching the genomes of early-diverging protists to study whether the possession of calmodulin is ancestral to all eukaryotes, the gene for calmodulin was identified in Trichomonas vaginalis. This flagellate is a member of the Parabasalia, one of the earliest lineages of recognized eukaryotes to have diverged. This sequence was used to isolate a homologous 1.

View Article and Find Full Text PDF
Article Synopsis
  • - The study looked at how Fusobacterium nucleatum, a bacteria linked to gum disease, breaks down glutamate, focusing on how this process produces acetate and butyrate.
  • - Using NMR spectroscopy and mass spectrometry, researchers found that the preferred pathway for processing glutamate was the hydroxyglutarate pathway, as indicated by specific labeling patterns of acetate and butyrate.
  • - The research also demonstrated that the labeling of butyrate at different carbon positions resulted from a combination of pathways, confirming the involvement of acetate in butyrate synthesis.
View Article and Find Full Text PDF