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1.
PLoS Comput Biol ; 17(7): e1009183, 2021 07.
Article in English | MEDLINE | ID: mdl-34260589

ABSTRACT

Coronavirus disease 2019 (COVID-19) is an acute infection of the respiratory tract that emerged in December 2019 in Wuhan, China. It was quickly established that both the symptoms and the disease severity may vary from one case to another and several strains of SARS-CoV-2 have been identified. To gain a better understanding of the wide variety of SARS-CoV-2 strains and their associated symptoms, thousands of SARS-CoV-2 genomes have been sequenced in dozens of countries. In this article, we introduce COVIDomic, a multi-omics online platform designed to facilitate the analysis and interpretation of the large amount of health data collected from patients with COVID-19. The COVIDomic platform provides a comprehensive set of bioinformatic tools for the multi-modal metatranscriptomic data analysis of COVID-19 patients to determine the origin of the coronavirus strain and the expected severity of the disease. An integrative analytical workflow, which includes microbial pathogens community analysis, COVID-19 genetic epidemiology and patient stratification, allows to analyze the presence of the most common microbial organisms, their antibiotic resistance, the severity of the infection and the set of the most probable geographical locations from which the studied strain could have originated. The online platform integrates a user friendly interface which allows easy visualization of the results. We envision this tool will not only have immediate implications for management of the ongoing COVID-19 pandemic, but will also improve our readiness to respond to other infectious outbreaks.


Subject(s)
COVID-19/epidemiology , Cloud Computing , Computational Biology/methods , User-Computer Interface , COVID-19/genetics , COVID-19/physiopathology , COVID-19/virology , Humans , Risk Factors , SARS-CoV-2/genetics , Severity of Illness Index
2.
CMAJ Open ; 7(3): E546-E561, 2019.
Article in English | MEDLINE | ID: mdl-31484650

ABSTRACT

BACKGROUND: A massive hemorrhage protocol (MHP) enables rapid delivery of blood components in a patient who is exsanguinating pending definitive hemorrhage control, but there is variability in MHP implementation rates, content and compliance owing to challenges presented by infrequent activation, variable team performance and patient acuity. The goal of this project was to identify the key evidence-based principles and quality indicators required to develop a standardized regional MHP. METHODS: A modified Delphi consensus technique was performed in the spring and summer of 2018. Panellists used survey links to independently review and rate (on a 7-point Likert scale) 43 statements and 8 quality indicators drafted by a steering committee composed of transfusion medicine specialists and technologists, and trauma physicians. External stakeholder input from all hospitals in Ontario was sought. RESULTS: Three rounds were held with 36 experts from diverse clinical backgrounds. Consensus was reached for 42 statements and 8 quality indicators. Additional modifications from external stakeholders were incorporated to form the foundation for the proposed MHP. INTERPRETATION: This MHP template will provide the basis for the design of an MHP toolkit, including specific recommendations for pediatric and obstetrical patients, and for hospitals with limited availability of blood components or means to achieve definitive hemorrhage control. We believe that harmonization of MHPs in our region will simplify training, increase uptake of evidence-based interventions, enhance communication, improve patient comfort and safety, and, ultimately, improve patient outcomes.

3.
Injury ; 50(1): 46-53, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30449459

ABSTRACT

BACKGROUND: Massive hemorrhage protocols (MHP) are critical to standardized delivery of timely, safe, and resource-effective coordinated care for patients with life-threatening bleeding. METHODS: A standardized MHP survey was sent to all hospitals (n = 150) in Ontario with a transfusion service. This study aim was to determine the proportion of hospitals with an MHP and assess for variability. RESULTS: The overall survey completion rate was 133 of 150 hospitals (89%) (remaining 17 providing negative affirmation that they did not have an MHP). An MHP was in place at 97 of 150 (65%) hospitals (60% of small (<5000 red cell units/year) vs. 91% of medium/large). A total of 10 different names of protocols were reported, with "Massive Transfusion Protocol" (68%) predominating. Activation criteria were present in 82 of 97 (85%); commonly activated based on volume of blood loss (70%). Blood work was drawn at the discretion of the physician (37%) or at predefined intervals (31%; majority every 60 min). Common routine laboratory tests performed were CBC (87%) and INR (84%). Fibrinogen testing was available at 88 (66%) of 133 reporting hospitals and part of the standard testing at 73 of 97 (75%) hospitals with an MHP. Median targets of hemostatic resuscitations, stated in the protocol at 49% of hospitals with an MHP, were: platelets >50 × 109/L, INR < 1.8, fibrinogen >1.5 g/L, and hemoglobin >70 g/L. Protocol required patient temperature monitoring in 65% and specified a reversal plan for patients on anticoagulants in 59%. At 36% of sites all patients are initially managed with O RhD negative blood. Overall, 61% of sites issue blood in predefined packs (vs. on demand). Hemostatic agents in protocols included: tranexamic acid (70%), prothombin complex concentrate (14%), fibrinogen concentrate (13%), and recombinant FVIIa (4%). Quality metrics were tracked in 32% of hospitals. CONCLUSIONS: A third of hospitals lack formal MHPs, with the majority lacking in smaller hospitals. The survey results indicate that there is marked variability in all key aspects of the reported MHPs. This may be due to differences in hospital resources and personnel, lack of supporting evidence to dictate requirements, and differences in knowledge base of the individuals involved in protocol setting.


Subject(s)
Blood Transfusion/statistics & numerical data , Hemorrhage/therapy , Resuscitation , Wounds and Injuries/therapy , Clinical Protocols , Health Care Surveys , Hemorrhage/mortality , Hemorrhage/prevention & control , Hemostatics , Humans , Ontario/epidemiology , Practice Guidelines as Topic , Resuscitation/methods , Resuscitation/statistics & numerical data , Wounds and Injuries/mortality
4.
Nurs Child Young People ; 27(10): 26-31, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26654027

ABSTRACT

Statutory guidance for promoting the health and wellbeing of looked after children stipulates that children and young people in the care system should receive health assessments on entry to care, and thereafter at six-monthly intervals for children aged under five and annually for those aged five to 18 years. Heart of England NHS Foundation Trust works in partnership with the local authority and clinical commissioners to meet the needs of local looked after children. It was found that many of these children and young people were refusing to have health assessments. This longitudinal study identified blocks to engagement, and explored alternative strategies to build compliance and participation. Findings have demonstrated that using a multi-agency and child-centred approach is effective in engaging 'hard to reach' children and young people.


Subject(s)
Community-Institutional Relations , Adolescent , Child , Child Health Services/organization & administration , Child, Preschool , England , Health Priorities , Humans , State Medicine
5.
Biophys J ; 109(5): 1038-48, 2015 Sep 01.
Article in English | MEDLINE | ID: mdl-26331261

ABSTRACT

We provide the first direct experimental comparison, to our knowledge, between the internal dynamics of calcitonin-gene-related peptide (CGRP) and amylin (islet amyloid polypeptide, IAPP), two intrinsically disordered proteins of the calcitonin peptide family. Our end-to-end contact formation measurements reveal that in aqueous solution (i.e., in the absence of structure-inducing organic solvents) CGRP preferentially populates conformations with short end-to-end distances. However, the end-to-end distance of CGRP is larger than that of IAPP. We find that electrostatic interactions can account for such a difference. At variance with previous reports on the secondary structure of CGRP, we find that the end-to-end distance of the peptide increases with decreasing pH and salt concentration, due to Coulomb repulsion by charged residues. Interestingly, our data show that the reconfiguration dynamics of CGRP is significantly slower than that of human IAPP in water but not in denaturant, providing experimental evidence for roughness in the energy landscape, or internal friction, in these peptides. The data reported here provide both structural and dynamical information that can be used to validate results from molecular simulations of calcitonin family peptides in aqueous solution.


Subject(s)
Calcitonin Gene-Related Peptide/chemistry , Calcitonin Gene-Related Peptide/metabolism , Intrinsically Disordered Proteins/chemistry , Intrinsically Disordered Proteins/metabolism , Islet Amyloid Polypeptide/chemistry , Islet Amyloid Polypeptide/metabolism , Amino Acid Sequence , Humans , Models, Molecular , Molecular Sequence Data , Protein Conformation , Static Electricity
6.
Biophys J ; 105(7): 1661-9, 2013 Oct 01.
Article in English | MEDLINE | ID: mdl-24094407

ABSTRACT

We report for the first time, to our knowledge, that the N-terminal loop (N_loop) of amylin (islet amyloid polypeptide (IAPP) residues 1-8) forms extremely long and stable non-ß-sheet fibers in solution under the same conditions in which human amylin (hIAPP) forms amyloid fibers. This observation applies to the cyclic, oxidized form of the N_loop but not to the linear, reduced form, which does not form fibers. Our findings indicate a potential role of direct N_loop-N_loop interactions in hIAPP aggregation, which has not been previously explored, with important implications for the mechanism of hIAPP amyloid fiber formation, the inhibitory action of IAPP variants, and the competition between ordered and disordered aggregation in peptides of the calcitonin peptide family.


Subject(s)
Islet Amyloid Polypeptide/chemistry , Polymerization , Amino Acid Motifs , Amino Acid Sequence , Animals , Humans , Islet Amyloid Polypeptide/metabolism , Molecular Dynamics Simulation , Molecular Sequence Data , Protein Structure, Tertiary , Rats
7.
Phys Biol ; 9(6): 065001, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23196865

ABSTRACT

AFM images show that chromatin reconstituted on methylated DNA (meDNA) is compacted when imaged under water. Chromatin reconstituted on unmethylated DNA is less compacted and less sensitive to hydration. These differences must reflect changes in the physical properties of DNA on methylation, but prior studies have not revealed large differences between methylated and unmethylated DNA. Quasi-elastic light scattering studies of solutions of methylated and unmethylated DNA support this view. In contrast, AFM images of molecules at a water/solid interface yield a persistence length that nearly doubles (to 92.5 ± 4 nm) when 9% of the total DNA is methylated. This increase in persistence length is accompanied by a decrease in contour length, suggesting that a significant fraction of the meDNA changes into the stiffer A form as the more hydrophobic meDNA is dehydrated at the interface. This suggests a simple mechanism for gene silencing as the stiffer meDNA is more difficult to remove from nucleosomes.


Subject(s)
DNA Methylation , DNA/chemistry , DNA/genetics , Gene Silencing , DNA/ultrastructure , Humans , Hydrophobic and Hydrophilic Interactions , Microscopy, Atomic Force , Nucleosomes/chemistry , Nucleosomes/genetics , Nucleosomes/ultrastructure , Promoter Regions, Genetic , Telomerase/genetics
8.
J Biomed Opt ; 16(7): 078003, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21806295

ABSTRACT

We report experimental results on the inactivation of encephalomyocarditis virus, M13 bacteriophage, and Salmonella typhimurium by a visible femtosecond laser. Our results suggest that inactivation of virus and bacterium by a visible femtosecond laser involves completely different mechanisms. Inactivation of viruses by a visible femtosecond laser involves the breaking of hydrogen∕hydrophobic bonds or the separation of the weak protein links in the protein shell of a viral particle. In contrast, inactivation of bacteria is related to the damage of their DNAs due to irradiation of a visible femtosecond laser. Possible mechanisms for the inactivation of viruses and bacteria are discussed.


Subject(s)
Bacteriophage M13/radiation effects , Encephalomyocarditis virus/radiation effects , Lasers, Solid-State/therapeutic use , Salmonella typhimurium/radiation effects , Animals , Cattle , Circular Dichroism , DNA, Viral/radiation effects , Microscopy, Atomic Force , Microscopy, Fluorescence, Multiphoton , Serum Albumin, Bovine/chemistry , Serum Albumin, Bovine/radiation effects , Spectrometry, Fluorescence , Spectrum Analysis, Raman , Virion/radiation effects
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