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1.
J Can Assoc Gastroenterol ; 2(Suppl 1): S81-S91, 2019 Feb.
Article in English | MEDLINE | ID: mdl-31294388

ABSTRACT

BACKGROUND: Health research in Canada is funded by government, health charities, foundations and industry. We investigated levels of IBD research funding and the scientific impact of this research in Canada between 2013 and 2017. METHODS: An analysis of global and Canadian funding in IBD research was conducted using the Canadian Institutes of Health Research (CIHR) Funded Research Database and UberResearch's Dimensions platform. Examples of priority-driven and investigator-initiated IBD research in Canada are provided. Bibliometric analysis was used to assess the quality of IBD research output in Canada. RESULTS: Total funding for IBD research Canada between 2013 and 2017 was over $119 million Canadian dollars (CAD), with CIHR, the largest funder, contributing almost $66 million CAD, and Crohn's and Colitis Canada, investing more than $32 million CAD. This ranks Canada fourth internationally. A comparative analysis indicates that publications by Canadian IBD researchers have a greater impact than other Canadian and international comparators. When productivity and impact in IBD research are combined, Canada is among the top three in the world. CONCLUSIONS: Investment in IBD research in Canada has resulted in the development of a strong collaborative group of researchers producing impactful, world-class research. On all measures of academic productivity and influence, Canada ranks in the top two or three internationally. The challenges ahead are to continue to fund innovative IBD research and grow the next generation of IBD researchers while moving research findings into changes in health policy and practice in order to benefit affected patients and their families-and ultimately, to find the cause(s) and identify the cure(s).

2.
Am J Physiol Endocrinol Metab ; 309(4): E370-9, 2015 Aug 15.
Article in English | MEDLINE | ID: mdl-26081282

ABSTRACT

A common complication of type 1 diabetes mellitus is diabetic ketoacidosis (DKA), a state of severe insulin deficiency. A potentially harmful consequence of DKA therapy in children is cerebral edema (DKA-CE); however, the mechanisms of therapy-induced DKA-CE are unknown. Our aims were to identify the DKA treatment factors and membrane mechanisms that might contribute specifically to brain cell swelling. To this end, DKA was induced in juvenile mice with the administration of the pancreatic toxins streptozocin and alloxan. Brain slices were prepared and exposed to DKA-like conditions in vitro. Cell volume changes were imaged in response to simulated DKA therapy. Our experiments showed that cell swelling was elicited with isolated DKA treatment components, including alkalinization, insulin/alkalinization, and rapid reductions in osmolality. Methyl-isobutyl-amiloride, a nonselective inhibitor of sodium-hydrogen exchangers (NHEs), reduced cell swelling in brain slices elicited with simulated DKA therapy (in vitro) and decreased brain water content in juvenile DKA mice administered insulin and rehydration therapy (in vivo). Specific pharmacological inhibition of the NHE1 isoform with cariporide also inhibited cell swelling, but only in the presence of the anion transport (AT) inhibitor 4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid. DKA did not alter brain NHE1 isoform expression, suggesting that the cell swelling attributed to the NHE1 was activity dependent. In conclusion, our data raise the possibility that brain cell swelling can be elicited by DKA treatment factors and that it is mediated by NHEs and/or coactivation of NHE1 and AT.


Subject(s)
Anions/metabolism , Brain Edema/etiology , Diabetes Mellitus, Type 1/complications , Diabetic Ketoacidosis/etiology , Diabetic Ketoacidosis/therapy , Ion Transport/physiology , Sodium-Hydrogen Exchangers/physiology , Alloxan , Animals , Brain/pathology , Brain Edema/metabolism , Diabetes Mellitus, Experimental/complications , Diabetes Mellitus, Experimental/pathology , Diabetes Mellitus, Type 1/pathology , Diabetic Ketoacidosis/pathology , Fluid Therapy/adverse effects , Insulin/adverse effects , Mice , Organ Culture Techniques , Osmolar Concentration , Sodium-Hydrogen Exchangers/metabolism , Streptozocin
3.
Stem Cell Reports ; 2(6): 810-24, 2014 Jun 03.
Article in English | MEDLINE | ID: mdl-24936468

ABSTRACT

Adult forebrain definitive neural stem cells (NSCs) comprise a subpopulation of GFAP-expressing subependymal cells that arise from embryonic fibroblast growth factor (FGF)-dependent NSCs that are first isolated from the developing brain at E8.5. Embryonic FGF-dependent NSCs are derived from leukemia inhibitory factor (LIF)-responsive, Oct4-expressing primitive NSCs (pNSCs) that are first isolated at E5.5. We report the presence of a rare population of pNCSs in the periventricular region of the adult forebrain. Adult-derived pNSCs (AdpNSCs) are GFAP(-), LIF-responsive stem cells that display pNSC properties, including Oct4 expression and the ability to integrate into the inner cell mass of blastocysts. AdpNSCs generate self-renewing, multipotent colonies that give rise to definitive GFAP(+) NSCs in vitro and repopulate the subependyma after the ablation of GFAP(+) NSCs in vivo. These data support the hypothesis that a rare population of pNSCs is present in the adult brain and is upstream of the GFAP(+) NSCs.


Subject(s)
Brain/cytology , Brain/metabolism , Nerve Tissue Proteins/metabolism , Neural Stem Cells/cytology , Neural Stem Cells/metabolism , Animals , Glial Fibrillary Acidic Protein , Mice , Neurons/cytology , Neurons/metabolism , Octamer Transcription Factor-3/metabolism
4.
Can J Gastroenterol ; 27(12): 717-20, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24340317

ABSTRACT

BACKGROUND: Funders of health research in Canada seek to determine how their funding programs impact research capacity and knowledge creation. OBJECTIVE: To evaluate the impact of a focused grants and award program that was cofunded by the Canadian Institutes of Health Research Institute of Nutrition, Metabolism and Diabetes, and the Canadian Association of Gastroenterology; and to measure the impact of the Program on the career paths of funded researchers and assess the outcomes of research supported through the Program. METHODS: A survey of the recipients of grants and awards from 2000 to 2008 was conducted in 2012. The CIHR Funding Decisions database was searched to determine subsequent funding; a bibliometric citation analysis of publications arising from the Program was performed. RESULTS: Of 160 grant and award recipients, 147 (92%) completed the survey. With >$17.4 million in research funding, support was provided for 131 fellowship awards, seven career transition awards, and 22 operating grants. More than three-quarters of grant and award recipients continue to work or train in a research-related position. Combined research outputs included 545 research articles, 130 review articles, 33 book chapters and 11 patents. Comparative analyses indicate that publications supported by the funding program had a greater impact than other Canadian and international comparators. CONCLUSIONS: Continuity in support of a long-term health research funding partnership strengthened the career development of gastroenterology researchers in Canada, and enhanced the creation and dissemination of new knowledge in the discipline.


Subject(s)
Biomedical Research/economics , Career Choice , Gastroenterology/economics , Publications/statistics & numerical data , Research Support as Topic , Canada , Fellowships and Scholarships , Foundations/economics , Government Agencies/economics , Humans , Public-Private Sector Partnerships , Societies, Medical/economics
5.
Microcirculation ; 20(6): 534-43, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23441883

ABSTRACT

OBJECTIVE: To determine if the DKA-induced inflammation in juvenile mice provokes activation and dysfunction of CVECs. METHODS: DKA in juvenile mice was induced with administration of STZ and ALX. Blood from DKA mice was assessed for cytokines and soluble cell adhesion proteins, and either DKA plasma or exogenous compounds were applied to immortalized bEND3. RESULTS: DKA increased circulating levels of IL-6, IL-8(KC), MCP-1, IL-10, sE-selectin, sICAM-1, and sVCAM-1. Stimulation of bEND3 with DKA plasma caused cellular activation (increased ROS and activation of NF-κΒ), upregulation of a proadhesive phenotype (E-selectin, ICAM-1, and VCAM-1), and increased leukocyte-bEND3 interaction (leukocyte rolling/adhesion). TEER, a measure of bEND3 monolayer integrity, was decreased by DKA plasma. Activation and dysfunction of bEND3 with DKA plasma were suppressed by plasma heat treatment (56°C, 1 hour) and replicated with the application of DKA recombinant cytomix (IL-6, IL-8[KC], MCP-1, and IL-10), implicating circulating inflammatory protein(s) as mediators. Treatment of bEND3 with ß-OH-butyrate, the main ketone elevated in DKA, failed to mimic the DKA plasma-induced activation and dysfunction of bEND3. CONCLUSIONS: DKA elicits systemic inflammation associated with CVEC activation and dysfunction, possibly contributing to DKA-associated intracranial microvascular complications.


Subject(s)
Brain/metabolism , Cell Adhesion Molecules/metabolism , Diabetic Ketoacidosis/metabolism , Endothelial Cells/metabolism , Leukocyte Rolling , Leukocytes/metabolism , Animals , Brain/pathology , Cells, Cultured , Cytokines/metabolism , Diabetic Ketoacidosis/pathology , Endothelial Cells/pathology , Inflammation/metabolism , Inflammation/pathology , Leukocytes/pathology , Male , Mice
6.
Pediatr Crit Care Med ; 12(3): 319-24, 2011 May.
Article in English | MEDLINE | ID: mdl-20625342

ABSTRACT

OBJECTIVES: 1) To determine the levels of glial fibrillary acidic protein (GFAP) in both cerebrospinal fluid and serum; 2) to determine whether serum GFAP levels correlate with functional outcome; and 3) to determine whether therapeutic hypothermia, as compared with normothermia, alters serum GFAP levels in children with severe traumatic brain injury (TBI). DESIGN: Laboratory-based analyses; postrandomized, controlled trial. SETTING: Four Canadian pediatric intensive care units and a university-affiliated laboratory. PATIENTS: Twenty-seven children, aged 2-17 yrs, with severe TBI (Glasgow Coma Scale score of ≤ 8). INTERVENTIONS: Hypothermia therapy (32.5°C) for 24 hrs with cooling started within 8 hrs of injury and rewarming at a rate of 0.5°C every 2 hrs or normothermia (37.0°C). MEASUREMENTS AND MAIN RESULTS: GFAP was measured in cerebrospinal fluid and serum, using enzyme-linked immunosorbent assay. Levels of GFAP were maximal on day 1 post-TBI, with cerebrospinal fluid GFAP (15.5 ± 6.1 ng/mL) 25-fold higher than serum GFAP (0.6 ± 0.2 ng/mL). Cerebrospinal fluid GFAP normalized by day 7, whereas serum GFAP decreased gradually to reach a steady state by day 10. Serum GFAP measured on day 1 correlated with Pediatric Cerebral Performance Category scores determined at 6 months post-TBI (ρ = 0.527; p = .008) but failed to correlate with the injury scoring on admission, physiologic variables, or indices of injury measured on computerized tomography imaging. The areas under the receiver operating characteristic curves for pediatric intensive care unit day 1 serum GFAP in determining good outcome were 0.80 (pediatric cerebral performance category, 1-2; normal-mild disability) and 0.91 (pediatric cerebral performance category, 1-3; normal-moderate disability). For a serum GFAP cutoff level of 0.6 ng/mL, sensitivity and specificity were 88% to 90% and 43% to 71%, respectively. Serum GFAP levels were similar among children randomized to either therapeutic hypothermia or normothermia. CONCLUSIONS: GFAP was markedly elevated in cerebrospinal fluid and serum in children after severe TBI and serum GFAP measured on pediatric intensive care unit day 1 correlated with functional outcome at 6 months. Hypothermia therapy did not alter serum GFAP levels compared with normothermia after severe TBI in children. Serum GFAP concentration, together with other biomarkers, may have prognostic value after TBI in children.


Subject(s)
Brain Injuries/physiopathology , Glial Fibrillary Acidic Protein/cerebrospinal fluid , Adolescent , Brain Injuries/cerebrospinal fluid , Brain Injuries/metabolism , Child , Child, Preschool , Glasgow Coma Scale , Humans , Trauma Severity Indices
7.
Pediatr Res ; 61(3): 301-6, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17314687

ABSTRACT

Cerebral edema in diabetic ketoacidosis (DKA-CE) occurs primarily in children and can develop during DKA therapy. The treatment factors contributing to DKA-CE remain elusive. Our objectives were to characterize an age-appropriate DKA mouse model and to determine which DKA therapies contribute to DKA-CE. Juvenile mice were briefly fed a high-fat diet and injected with two pancreatic beta-cell toxins: streptozocin and alloxan. Severe insulin and leptin deficiencies associated with hyperosmolar ketoacidosis rapidly developed, indicating DKA. DKA mice were treated with re-hydration +/- insulin and brain water content (BWC) measured as an indicator of DKA-CE. As expected, glucose and beta-OH-butyrate corrected in DKA mice that received rehydration and insulin. BWC significantly increased above control levels only in DKA mice that received combined insulin and bicarbonate therapy, indicating the development of DKA-CE. Microscopically, DKA-CE brains had perineuronal and perivascular edema, with microvacuolation in the white matter tracts. These results indicate that insulin-deficient juvenile mice develop biochemical changes that are similar to those of DKA in children. Increased BWC was observed only in DKA mice that received combined insulin and bicarbonate therapy, suggesting that rapid systemic alkalinization in the presence of insulin may contribute to DKA-CE.


Subject(s)
Bicarbonates/toxicity , Brain Edema/etiology , Diabetic Ketoacidosis/complications , Diabetic Ketoacidosis/drug therapy , Insulin/toxicity , Animals , Bicarbonates/administration & dosage , Bicarbonates/therapeutic use , Brain Edema/pathology , Brain Edema/prevention & control , Child , Diabetes Mellitus, Experimental/complications , Disease Models, Animal , Drug Interactions , Humans , Insulin/administration & dosage , Insulin/therapeutic use , Male , Mice , Mice, Inbred C57BL
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