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Open Access
Computed tomography perfusion assessment of poor neurological outcome in comatose cardiac arrest patients (CANCCAP): a prospective study
(BMC, 2025-05-23) Shankar, Jai; Alcock, Susan; Wiens, Evan; Ayroso, Marco; Park, JaeYeon; Singh, Navjit; Blackwood, Benjamin ; Trivedi, Reva; Marin, Roman; Sinha, Namita; Trivedi, Anurag; Kirkpatrick, Iain; Essig, Marco; Schaffer, Stephen
Abstract Background Computed tomography perfusion (CTP) of the brain, are increasingly being employed for the assessment of critically ill patients admitted to intensive care units (ICU), including comatose cardiac arrest patients (CCAP). The purpose of our study was to validate the use of CTP in predicting in-hospital mortality in CCAPs. Method This prospective cohort study enrolled newly admitted adult CCAP, with an out of hospital cardiac arrest (OHCA) and were scheduled for admission to the ICU for further management. Just before ICU admission, CCAP underwent a routine CT scan of the head and CTP of whole head. The treating physicians remained blinded to the CTP results and all patients received standard management. The CTP maps were evaluated to determine a binary outcome of non-survivable brain injury (NSBI), by two independent neuroradiologists, blinded to each other’s assessment and to the clinical history of the patients. Results A total of 91 patients were enrolled and 90 (Male-78; mean age-62 years) were included in the final analysis. One patient declined consent. Of these, 42 individuals (47%) had in-hospital mortality. Patients with in-hospital mortality were older; had higher levels of creatinine, blood urea nitrogen, blood CO2 and lower pH, carbonate, and heart rate. In multivariate analysis, PCI was independently associated with reduction in-hospital mortality. CTP demonstrated exceptionally high specificity (100%; 95% CI 92–100%) and positive predictive value (100%; 95%CI 6.3–100%) for the prediction of NSBI. For CTP, Bennet’s S-score showed excellent agreement between the two readers (s = 0.82–0.95). Conclusion CTP was safe and demonstrated very high specificity and positive predictive value and may be used as an additional diagnostic tool for identifying patients at high risk of in-hospital mortality.
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Open Access
Erroneous calibration of esophageal pressure in case of airway closure
(BMC, 2025-05-02) Docci, Mattia; Beloncle, Francois; Lesimple, Arnaud; Piraino, Thomas; Raimondi Cominesi, Davide; Restivo, Andrea; Sousa, Mayson L. A.; Rezoagli, Emanuele; Mercat, Alain; Richard, Jean-Christophe; Brochard, Laurent
Abstract Airway closure results in a lack of communication between proximal and distal airways unless the airway pressure (Paw) overcomes the airway opening pressure (AOP). This has been described in patients undergoing mechanical ventilation with acute respiratory distress syndrome, obesity, hydrostatic pulmonary edema and during cardiopulmonary resuscitation. In these categories of patients, esophageal pressure (Pes) can guide the personalization of mechanical ventilation and calibration of the esophageal balloon is necessary to obtain reliable Pes measurements. The impact of airway closure has never been envisaged. This study investigated the impact of airway closure on the calibration of the esophageal balloon by the ∆Paw/∆Pes following a positive pressure occlusion test during passive mechanical ventilation. The calibration test was performed in twelve human cadavers with airway closure at end-expiration at different levels of positive end-expiratory pressure (PEEP) and at end-inspiration. The ∆Paw/∆Pes measured at end-expiration and at end-inspiration were significantly different when total PEEP was lower than AOP (estimated means 0.42 [0.40; 0.44] vs. 0.95 [0.92; 0.97], P < 0.001), while this difference was not observed when total PEEP was higher than AOP (estimated means 0.99 [0.92; 1.05] vs. 0.99 [0.92; 1.06], P = 0.854). These results were corroborated by observations during esophageal balloon calibration in two patients requiring Pes monitoring for clinical management. In case of airway closure, compression of the chest is not fully transmitted to the airways. This can lead to a conspicuous underestimation of the ∆Paw/∆Pes and poor reliability of this monitoring technique when the test takes place below AOP. Our results favor a positive pressure occlusion test performed during an end-inspiratory occlusion as the new standard of operative procedures for positioning and calibrating the esophageal balloon.
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Open Access
Genome mining of Leptographium wingfieldii, an invasive species in Canadian forests, and related taxa in the order Ophiostomatales for the characterization of secondary metabolites and ribozymes
(2025-05-06) Zubaer, Abdullah; Court, Deborah (Microbiology); Domaratzki, Mike (Computer Science); Smith, David R. (Western University); Hausner, Georg; Tremblay-Savard, Olivier
Leptographium wingfieldii is an invasive fungal species in Canadian forests which was originally isolated in Europe (France and Greece). Leptographium wingfieldii and other fungi in the order Ophiostomatales (Ascomycota) are vectored by arthropods, and they can be either pathogenic to tree species or cause blue stain on sapwood in conifer (and hardwood) species. These fungi are ecologically and economically significant due to their impact on forest ecosystems and lumber industry. Whole genome sequences were obtained from Leptographium wingfieldii and related fungi (including Leptographium procerum, Leptographium terebrantis, Grosmannia aureum, Ophiostoma minus, and Ophiostoma piliferum). The mitochondrial genomes of these fungi were assembled and found to contain autocatalytic group I and group II introns, intron-encoded homing endonucleases along with intron-encoded reverse transcriptase enzymes that have applications in genome editing. These elements contribute toward the genetic diversity observed among the mitochondrial genomes studied. The study provided information to generate a mitochondrial intron landscape, identified complex intron arrangements, and demonstrated the correlation of mitogenome expansion with the number of introns. The whole genome sequence data were also analyzed with regards to the presence of nuclear genome encoded biosynthetic gene clusters (BGCs). This effort identified the presence of 205 BGCs categorized into PKS I, PKS III, NRPS, RiPPS, Terpenes, and hybrid types and these could be sources for potential antimicrobials and industrially important chemical compounds. The study provides a platform for downstream biochemical characterization and heterologous expression of the identified genetic elements, facilitating their functional annotation and explore their potential for industrial applications.
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Open Access
Diagnosis of in-hospital mortality using admission CT perfusion in severe traumatic brain injury patients (ACT-TBI study)
(BMC, 2025-05-01) Shankar, Jai; Alcock, Susan; Leeies, Murdoch; Ayroso, Marco; Unrau, Sarah; Park, JaeYeon; Blackwood, Benjamin ; Trivedi, Reva; Marin, Roman; Raja, Muhammed; Sinha, Namita; Trivedi, Anurag; Essig, Marco; Martin, Douglas; Grierson, Robert; Zeiler, Frederick A.
Abstract Background Severe traumatic brain injury (TBI) stands as the leading cause of post-injury hospitalization, disability, and mortality globally. Imaging serves as a cornerstone in the assessment of patients with severe TBI and CT Perfusion (CTP) has emerged as an early prognostic tool. Our study aims to validate CTP features of non-survivable brain injury, upon hospital admission to characterize in-hospital mortality, through a well-powered prospective cohort study. Methods In a prospective cohort study, adult patients with severe TBI were recruited to undergo whole head CTP at the time of their first imaging. Interpretation of the CTP images were conducted by two independent neuroradiologists (JS and ME), blinded to clinical results and each other’s assessment. Non-survivable brain injury was defined as a matched decrease of cerebral blood flow (CBF) and cerebral blood volume (CBV) in the brainstem. The results of CTP were not disclosed to the clinical team providing patient care, and the patients received standard institutional management. The primary outcome was a binary outcome of in-hospital mortality. The primary validity analysis involved calculating sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for features of non-survivable brain injury on admission CTP compared to in-hospital mortality, along with 95% confidence intervals. Results Out of the 201 patients initially enrolled in the study, 195 patients (mean age 42.9 years; Male- 160, 82%) were included in the final analysis. Among the participants, a total of 55 patients (28.2%) died during their hospital stay. The odds ratio (OR) was highest for the presence of intracranial hemorrhage (ICH) (OR-20.25; 95% CI- 7.08–71.80, p < 0.001) and gun shot wound (GSW) (OR-22.67; 95% CI- 3.66–257.5, p = 0.003), which were independently associated with in-hospital mortality. With every decade of age, there was 1.77 times of (95% CI- 1.37–2.36, p < 0.001) higher odds of in-hospital mortality. Of the 55 patients with in-hospital mortality, 17 (31%) met the criteria of non-survival brain injury on the CTP at the time of hospital admission. Both CTP and CT-angiogram (CTA)A had 100% specificity and PPV. The highest sensitivity of 33% and NPV of 80% was seen with non-survivable criteria of CTP. As a result, this variable exhibited the highest accuracy of 82% with an area under the curve (AUC) of 0.67. The inter-rater reliability for CTP ranged from poor (kappa = 0.07) to fair (kappa = 0.44), indicating variability in agreement between raters. In contrast, the inter-rater reliability for CTA scales ranged from fair (kappa = 0.39) to substantial (kappa = 0.79), suggesting more consistent agreement among raters. CTP was found to be safe as no patients experience any complications associated with CTP. Conclusion CTP features of non-survivable brain injury showed very high specificity and positive predictive value for diagnosing in-hospital mortality in patients with severe TBI.
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Open Access
Functional work disability from the perspectives of persons with systemic lupus erythematosus: a qualitative thematic analysis
(BMC, 2025-05-26) Nowrouzi-Kia, Behdin; Howe, Aaron S.; Li, Anson; Tan, Jeremy; Saade-Cleves, Natalia; Jules, Kevon; Sadek, Malak; Bani-Fatemi, Ali; Avina-Zubieta, Antonio; Fox, Mary T.; Shaw, William; Haaland, Derek; Pope, Janet; Fortin, Paul R.; Bingham, Kathleen S.; Peschken, Christine; Reynolds, Jennifer; Ivory, Catherine; Gladman, Dafna D.; Urowitz, Murray B.; Sanchez-Guerrero, Jorge; Lim, Lily S. H.; Keeling, Stephanie; Katz, Patti; Kavkan, Mahta; Bonilla, Dennisse; Nielsen, Wils; Touma, Zahi
Abstract Background Systemic lupus erythematosus (SLE) disease symptoms that can significantly restrict work ability and work participation resulting in reduced mental well-being. This study investigates the significant impact of work participation and disability on the mental wellbeing, health-related quality of life, and disease-related outcomes in individuals with SLE. Methods With the objective of creating an SLE-related functional profile rooted in work disability (WD) prevention, 46 SLE patients were purposively recruited from Canadian medical centres. Through semi-structured interviews guided by a WD prevention framework, factors associated with WD and lived experiences of SLE-related WD were qualitatively explored. Braun and Clarke’s six-stage inductive thematic analysis was used to organize the data. Results Most participants experienced some form of work disability across their employment history related to their clinical manifestations of SLE, including hospitalizations, physical limitations, fatigue, and neurocognitive symptoms (e.g. brain fog). Thematic analysis revealed three key themes: (a) the influence of illness experience on work, (b) the stigmatization of illness disclosure, and (c) the availability of workplace resources/accommodations. Participants emphasized the desirability of work with reduced physical and mental demands, increased personal control, and workplace flexibility to prevent WD. Conclusion The study underscores the need for a collaborative, multi-component, and multidisciplinary intervention targeting psychosocial and workplace factors to establish a goal-oriented preventative framework, potentially improving WD outcomes in SLE individuals.
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Open Access
Contextual factors related to aging determine force-based manipulation dosage: a prospective cross-sectional study
(BMC, 2025-05-21) Maiers, Michele J.; Sundin, Alexander R.; Oster, Ryan J.; Kreul, Steven; Malone, Quinn; Passmore, Steven R.
Abstract Background Contextual factors influence clinicians’ delivery of force-based manipulation (FBM), like spinal manipulative therapy (SMT). It is particularly important to discern how contextual factors interact with therapeutic forces delivered to an older adult population, to minimize risk and identify ideal dosage. This study aimed to determine whether contextual factors pertaining to aging result in the modulation of kinetic and kinematic parameters used by experienced clinicians when delivering SMT. Methods Participants were randomly presented with a series of 12 AI-generated patient vignettes, featuring both visual and auditory content and representing varying age-related contextual factors. Factors included chronological (35-, 65- and 85-year-old), pathological (“healthy” vs degenerative spine), and felt (perceived as “young” vs. “old”) age. Participants delivered SMT to a human analogue manikin based on each vignette, presented six times in randomized order. Kinetic and kinematic parameters were collected and analyzed for differences between “young” and “old” contextual factors of age, using a 3-way repeated measures ANOVA model. Results Sixteen licensed chiropractors (8 female, 8 male) participated, with an average age of 45.4 (SD = 9.7, range 34–64) years and 18.3 (SD = 10.8, range 5–39) years of experience. A main effect in peak force was found for both chronological (F(2,30) = 26.18; p <.001, ηp2 = 0.636) and pathological age (F(1,15) = 11.58; p =.004, ηp2 = 0.436), following a stepwise progression of decreased force with increased age and with pathology. No statistically significant differences were found in peak force based on felt age, or in time to peak force for any factor. A main effect was found for chronological age with peak acceleration (F(2,20) = 9.50; p <.001, ηp2 = 0.487) and peak velocity (F(2,20) = 7.20; p =.004, ηp2 = 0.419), but not for pathological or felt age. There was a significant difference in time to peak velocity for felt age (F(1,10) = 12.23; p =.006, ηp2 = 0.550), with a shorter time to peak velocity in response to vignettes with older felt age. Conclusion Contextual factors of aging modulated certain kinetic and kinematic characteristics when delivering SMT. This provides evidence that practitioners differentially discern aspects of aging to inform how they deliver FBM dosage. Future research is needed to identify ideal kinetic and kinematic characteristics based on considerations of aging.
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Open Access
Rural community-based participatory research with families of people who use drugs: key considerations from a multi-provincial research partnership
(BMC, 2025-05-30) Mathias, Holly; Duff, Elsie; Schulz, Petra; Auger, Sarah; Gravel-Ouellette, Antoinette; Lockhart, Teresa; McCorriston, Willi; McCrindle, Jenn; Mirza, Nyal; Pijl, Em; Savard, Tyla; Hyshka, Elaine
Abstract Background North America continues to contend with an unregulated drug crisis that is impacting communities of all sizes. Community-based participatory research that meaningfully engages people who use drugs, families, and their wider communities is one way of advancing social justice and improving population health. As more community-academic partnerships are formed in this space, some organizations have launched guidelines and considerations for engaging in community-based participatory research (CBPR). However, to our knowledge, none provide guidance for engaging in CBPR with people who use drugs and their families in rural settings. Main body This paper presents insights gained from our experiences collaborating to conduct CBPR with families providing unpaid support for people who use drugs in rural Canada. Key considerations are thematically organized in four sections: Dreaming (Building the team and setting a vision), Designing (Key definitions, budget and ethical consideration), Doing (Bringing research to life), and Disseminating (Moving research into action). Conclusions By building on existing principles and guidelines for working with PWUD and their families, these considerations will be a valuable resource for other partnerships seeking to engage in community-based participatory substance use research in rural settings.
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Open Access
Evaluation of physical and antioxidant properties of pigmented barley tortillas
(2025-04-24) Hatzir, Tomer; Badea, Ana (Food and Human Nutritional Sciences); Sorenson, John (Chemistry); Beta, Trust
Barley contains bioactive compounds like β-glucan and polyphenols that promote health. Food processing, while necessary, can change barley's physical properties and adversely affect polyphenols' antioxidant activity through heat and the food matrix. Thus, identifying compounds post-production, including new chemical structures, is essential. Five barley genotypes (CDC Rattan, CDC McGwire, Roseland, HB21147, and HB21148) produced tortillas at varying pH levels (1, 3, 5, 7). Their texture and physical properties were assessed. Identification and quantification were achieved through high-performance liquid chromatography (HPLC) with standards. Assays on the acidified ethanol extract measured the total phenolic and anthocyanin content, along with antioxidant properties, which were evaluated via in vitro and ex vivo methods. CDC Rattan tortillas decreased in thickness significantly between pH 1 and 7. At pH 5, extensibility was lower, with the hardest texture across genotypes. HB21148 recorded the highest total phenolic (14.0±1.2 mg gallic acid equivalent/g) and total anthocyanin content (313.9±33.4 cyanidin-3-glucoside equivalent/kg) among raw forms. Catechin was most concentrated in HB21148, followed by HB21147. Roseland exhibited the highest trans-cinnamic acid (13.5±0.5 mg/kg). Gentisic acid appeared only at pH 5 in genotypes with high β-glucan, HB21147 and CDC Rattan. Antioxidant activities were similar at pH 3 and 7 per the FRAP assay. HB21147 and Roseland showed parallel activity across pH levels with the ABTS method. Caco-2 cell tests found CDC Rattan enriched with anthocyanins resulted in significantly higher CAA (cellular antioxidant activity) than HB21148 at 200 μg/ml. The study suggests pH 3 optimizes antioxidant properties with minimal texture impact, potentially through new compounds involving β-glucan and polyphenols. These insights may aid in developing food products that integrate natural bioactive compounds for health benefits.
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Open Access
An Evaluation of Handheld Ultrasonography in Comparison to MRI for the Diagnosis of Temporomandibular Joint Disorders
(2025-10-11) Brown, Meagan; Todescan, Reynaldo; Bhullar, Raj; Shah, Adnan; Elgazzar, Reda; Dale, Catherine; Shah, Adnan; Elgazzar, Reda; Dale , Catherine
MRI is the gold standard of imaging modalities for the diagnoses of internal derangement (ID) of the Temporomandibular Joint (TMJ). MRI scans are non-invasive, use non-ionizing radiation, and provide valuable information on the position and morphology of joints, tissues and bony structures. MRI has disadvantages and patients with severe TMJ pain may find it difficult to complete a full TMJ scan series. The heavy demand for MRI utilization and resulting wait times prolong the interval between initial consultation and diagnosis. MRI is also expensive, inconvenient, and contraindicated in patients with certain metallic implants (Orhan & Aksoy, 2019). For these reasons, the author believes that finding an alternative diagnostic device for ID that is convenient and reliable is of critical importance. There is a limited body of encouraging evidence demonstrating that mobile ultrasound sonography (mUS), can act as a diagnostic adjunct to MRI for assessment of Temporomandibular Joint Disorders (TMD’s), including ID and Degenerative Joint Disease (DJD). The use of mUS has no known contraindications, is readily accessible, comparatively inexpensive, and requires no special preparation (Orhan & Aksoy, 2019). The purpose of this paper is to summarize the findings of original research into the Accuracy of handheld ultrasound sonography (HHU), in comparison to MRI, for the diagnoses of patients with TMD. The scans focussed on Anterior Disk Displacement (ADD) without reduction (ADDwoR), ADD with reduction (ADDwR) and arthritic changes (OA). Using a 95% CI and 5% p-value, when diagnosing ADDwoR, HHU was found to have a Sensitivity of 96.77%, Specificity of 100%, PPV of 100%, and NPV of 90%. When diagnosing ADDwR, Sensitivity was 76.50%, Specificity 100%, PPV 100%, and NPV 85.20%. The perfect Specificity means HHU is good at identifying patients that have a normal disc-condyle relationship and do not have ADD, while the perfect PPV means a high likelihood the tested patient has ADD. Results indicate that HHU is a highly Specific test, with no false negatives, and an acceptable Sensitive test, with few false positives. HHU, in conjunction with questionnaires and clinical examination, shows promise as a first line imaging modality and screen for MRI referral.
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Open Access
Examining inequalities in sugar sweetened beverage consumption using the 2004 and 2015 Canadian Community Health Surveys
(2025-04-29) Kidson, Mya; Lacroix, Emilie (Food and Human Nutritional Sciences); Shooshtari, Shahin (Community Health Sciences); Riediger, Natalie
Background: Sugar-sweetened beverages (SSBs) are associated with type 2 diabetes and other metabolic disorders, and as such, have become a popular health policy target. Reduction strategies include excise taxation, health education, and restrictions on the sale and marketing of SSBs in schools and public settings. Despite endorsement by health organizations and researchers, there is concern that these policies will not reduce health inequities for marginalized groups that consume SSB at higher frequencies and amounts. It is critical to examine changes in inequalities in SSB intake over time and in response to SSB policies. To examine inequalities in SSB intake, we are particularly interested in examining the association between smoking and SSB consumption. Objectives: Manuscript 1.0 aims to examine the associations between smoking and SSB consumption in 2004 and 2015. Manuscript 2.0 aims to examine the associations between relative income deprivation score and SSB consumption, comparing between 2004 and 2015. Methods: The 2004 and 2015 Canadian Community Health Surveys (CCHS) were used, which include representative samples of the Canadian population and detailed dietary data collected through 24-hour dietary recalls. Descriptive and analytical statistics were carried out to achieve the listed objectives, including developing logistic and linear regression models to determine the influence of predictors, such as relative income deprivation score (RID) and smoking, on binary SSB consumption and SSB-derived sugar amount. Results: Current smoking is associated with higher odds of SSB consumption (aOR: 1.86 [95% CI, 1.29, 2.68]), but not with SSB-derived sugar intake (Coeff: 0.10 [95% CI, -0.03, 0.23]), after adjusting for confounders. RID based on sex and province was not associated with SSB consumption in 2004 and 2015. Indigenous individuals had higher odds of consuming SSBs compared to non-Indigenous individuals (2004 OR = 2.65 [95% CI, 1.35, 5.20]), and 2015 (OR = 2.77 [95% CI, 1.39, 5.54]) with no significant change over time. There was no significant association between food insecurity and SSB consumption. Conclusion: Current smoking is associated with SSB intake, pointing to potential shared behavioural and socio-economic drivers. Persisting inequalities in SSB consumption between Indigenous and non-Indigenous populations emphasize the need for more equitable public health policies.