Investigations of urinary alpha-1 acid glycoprotein

The primary objective of this thesis was to investigate the mechanisms of post-exercise and altitude-induced proteinuria by measuring urinary alpha-1 acid glycoprotein (a1-AGP), a sensitive marker of glomerular leak. Following a review of literature providing the rationale for urinalysis of a1-AGP (Chapters 1 and 2), initial experimental chapters outlined the development and validation of a novel immunoturbidimetric assay for low-concentration a1-AGP (Chapter 3), as well as, the application and analysis completed to establish a normative reference range from collected samples and a systematic literature review (Chapter 4). The novel immunoassay was further utilised to evaluate the contribution of hypoxia to post-exercise and altitude-induced a1-AGP excretion, combining data from field- and chamber-based studies (Chapters 5 and 6). The final experimental chapter (Chapter 7) examined a1-AGP excretion during ascent to high altitude, but without an acute exercise stimulus. The synthesis of the thesis findings and discussion of future directions (Chapter 8) highlighted that profound systemic hypoxaemia did not influence the degree of post-exercise proteinuria, which was more attributable to exercise intensity, however, nocturnal oxygenation during ascent did influence altitude-induced a1-AGP excretion. Collectively, this thesis advances techniques for the urinalysis of a1-AGP and increases understanding of the causes of post-exercise and altitude-induced proteinuria

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Post-exercise urinary alpha-1 acid glycoprotein is not dependent on hypoxia

Proteinuria is a transient physiological phenomenon that occurs with a range of physical activities and during ascent to altitude. Exercise intensity appears to dictate the magnitude of postexercise proteinuria; however, evidence also indicates the possible contributions from exercise-induced hypoxemia or reoxygenation. Using an environmental hypoxic chamber, this crossover-designed study aimed to evaluate urinary alpha-1 acid glycoprotein (α1-AGP) excretion pre/postexercise performed in hypoxia (HYP) and normoxia (NOR). Sixteen individuals underwent experimental sessions in normoxia (NOR, 20.9% O(2)) and hypoxia (HYP, 12.0% O(2)). Sessions began with a 2-h priming period before completing a graded maximal exercise test (GXT) on a cycle ergometer, which was followed by continuation of exposure for an additional 2 h. Physiological responses (i.e., blood pressure, heart rate, and peripheral oxygenation), Lake Louise Scores (LLSs), and urine specimens (analyzed for albumin and α1-AGP) were collected pre- and postexercise (after 30, 60, and 120 min). Peak power output was significantly reduced in HYP (193 ± 45 W) compared with NOR (249 ± 59 W, P 0.05). Changes in urinary α1-AGP from pre- to post-30 min were not related to physiological responses or performance outcomes observed during GXT in NOR or HYP. Despite profound systemic hypoxemia with maximal exercise in hypoxia, postexercise α1-AGP excretion was not elevated above the levels observed following normoxic exercise. NEW & NOTEWORTHY By superimposing hypoxic exposure and maximal exercise, we were able to investigate the impact of hypoxia on postexercise proteinuria. Urinalysis for α1-AGP (via particle-enhanced immunoturbidimetry) in specimens collected pre-/postexercise enabled the sensitive detection of altered glomerular permeability. Data indicated that exercise intensity, rather than the degree of exercise-induced hypoxemia, determines postexercise proteinuria

At the Heart of It All: Emotions of Consequence for the Conceptualization of Caregiver-Reported Outcomes in the Context of Colorectal Cancer

Colorectal cancer (CRC) can be demanding for primary caregivers; yet, there is insufficient evidence describing the caregiver-reported outcomes (CROs) that matter most to caregivers. CROs refer to caregivers’ assessments of their own health status as a result of supporting a patient. The study purpose was to describe the emotions that were most impactful to caregivers of patients with CRC, and how the importance caregivers attribute to these emotions changed from diagnosis throughout treatment. Guided by qualitative Interpretive Description, we analyzed 25 caregiver and 37 CRC patient interviews, either as individuals or as caregiver-patient dyads (six interviews), using inductive coding and constant comparative techniques. We found that the emotional aspect of caring for a patient with CRC was at the heart of caregiving. Caregiver experiences that engendered emotions of consequence included: (1) facing the patient’s life-changing diagnosis and an uncertain future, (2) needing to be with the patient throughout the never-ending nightmare of treatment, (3) bearing witness to patient suffering, (4) being worn down by unrelenting caregiver responsibilities, (5) navigating their relationship, and (6) enduring unwanted change. The broad range of emotions important to caregivers contributes to comprehensive foundational evidence for future conceptualization and the use of CROs.Applied Science, Faculty ofPharmaceutical Sciences, Faculty ofAlumniNursing, School ofReviewedFacultyResearcherOthe

To share or not to share: communication of caregiver-reported outcomes when a patient has colorectal cancer

Background The importance of patient-centered measurement in cancer care has led to recognition of the potential for caregiver-reported outcomes to improve caregiver, patient and healthcare system outcomes. Yet, there is limited evidence to inform caregiver-reported outcome implementation. Our purpose was to generate evidence to inform the meaningful and constructive integration of caregiver-reported outcomes into cancer care to benefit caregivers, including exploration of the question of the extent to which these assessments should be shared with patients. We focused on caregivers of patients with colorectal cancer (CRC) because CRC is common, and associated caregiving can be complex. Results From our Interpretive Description analysis of qualitative interview data from 78 participants (25 caregivers, 37 patients, and 16 healthcare providers [HCPs]), we identified contrasting perspectives about the sharing of caregiver-reported outcome assessments with patients with CRC. Those who preferred open communication with both the patient and caregiver present considered this essential for supporting the caregiver. The participants who preferred private communication without the patient, cited concern about caregiver- and patient-burden and guilt. Recognizing these perspectives, HCPs described strategies used to navigate sensitivities inherent in preferences for open versus private communication. Conclusions The integration of caregiver-reported outcomes into cancer care will require careful consideration of caregiver and patient preferences regarding the communication of caregiver assessments to prevent additional burden.Applied Science, Faculty ofMedicine, Faculty ofPharmaceutical Sciences, Faculty ofNon UBCMedicine, Department ofNursing, School ofReviewedFacultyResearche

An Overview of Cancer in the First 315,000 <i>All of Us</i> Participants

Introduction: The NIH All of Us Research Program will have the scale and scope to enable research for a wide range of diseases, including cancer. The program’s focus on diversity and inclusion promises a better understanding of the unequal burden of cancer. Preliminary cancer ascertainment in the All of Us cohort from two data sources (self-reported versus electronic health records (EHR)) is considered. Materials and methods: This work was performed on data collected from the All of Us Research Program’s 315,297 enrolled participants to date using the Researcher Workbench, where approved researchers can access and analyze All of Us data on cancer and other diseases. Cancer case ascertainment was performed using data from EHR and self-reported surveys across key factors. Distribution of cancer types and concordance of data sources by cancer site and demographics is analyzed. Results and discussion: Data collected from 315,297 participants resulted in 13,298 cancer cases detected in the survey (in 89,261 participants), 23,520 cancer cases detected in the EHR (in 203,813 participants), and 7,123 cancer cases detected across both sources (in 62,497 participants). Key differences in survey completion by race/ethnicity impacted the makeup of cohorts when compared to cancer in the EHR and national NCI SEER data. Conclusions: This study provides key insight into cancer detection in the All of Us Research Program and points to the existing strengths and limitations of All of Us as a platform for cancer research now and in the future.</p

An Overview of Cancer in the First 315,000 All of Us Participants.

IntroductionThe NIH All of Us Research Program will have the scale and scope to enable research for a wide range of diseases, including cancer. The program's focus on diversity and inclusion promises a better understanding of the unequal burden of cancer. Preliminary cancer ascertainment in the All of Us cohort from two data sources (self-reported versus electronic health records (EHR)) is considered.Materials and methodsThis work was performed on data collected from the All of Us Research Program's 315,297 enrolled participants to date using the Researcher Workbench, where approved researchers can access and analyze All of Us data on cancer and other diseases. Cancer case ascertainment was performed using data from EHR and self-reported surveys across key factors. Distribution of cancer types and concordance of data sources by cancer site and demographics is analyzed.Results and discussionData collected from 315,297 participants resulted in 13,298 cancer cases detected in the survey (in 89,261 participants), 23,520 cancer cases detected in the EHR (in 203,813 participants), and 7,123 cancer cases detected across both sources (in 62,497 participants). Key differences in survey completion by race/ethnicity impacted the makeup of cohorts when compared to cancer in the EHR and national NCI SEER data.ConclusionsThis study provides key insight into cancer detection in the All of Us Research Program and points to the existing strengths and limitations of All of Us as a platform for cancer research now and in the future

An Overview of Cancer in the First 315,000 All of Us Participants.

IntroductionThe NIH All of Us Research Program will have the scale and scope to enable research for a wide range of diseases, including cancer. The program's focus on diversity and inclusion promises a better understanding of the unequal burden of cancer. Preliminary cancer ascertainment in the All of Us cohort from two data sources (self-reported versus electronic health records (EHR)) is considered.Materials and methodsThis work was performed on data collected from the All of Us Research Program's 315,297 enrolled participants to date using the Researcher Workbench, where approved researchers can access and analyze All of Us data on cancer and other diseases. Cancer case ascertainment was performed using data from EHR and self-reported surveys across key factors. Distribution of cancer types and concordance of data sources by cancer site and demographics is analyzed.Results and discussionData collected from 315,297 participants resulted in 13,298 cancer cases detected in the survey (in 89,261 participants), 23,520 cancer cases detected in the EHR (in 203,813 participants), and 7,123 cancer cases detected across both sources (in 62,497 participants). Key differences in survey completion by race/ethnicity impacted the makeup of cohorts when compared to cancer in the EHR and national NCI SEER data.ConclusionsThis study provides key insight into cancer detection in the All of Us Research Program and points to the existing strengths and limitations of All of Us as a platform for cancer research now and in the future

Retrotransposons Are the Major Contributors to the Expansion of the Drosophila ananassae Muller F Element

The discordance between genome size and the complexity of eukaryotes can partly be attributed to differences in repeat density. The Muller F element (∼5.2 Mb) is the smallest chromosome in Drosophila melanogaster, but it is substantially larger (>18.7 Mb) in D. ananassae. To identify the major contributors to the expansion of the F element and to assess their impact, we improved the genome sequence and annotated the genes in a 1.4-Mb region of the D. ananassae F element, and a 1.7-Mb region from the D element for comparison. We find that transposons (particularly LTR and LINE retrotransposons) are major contributors to this expansion (78.6%), while Wolbachia sequences integrated into the D. ananassae genome are minor contributors (0.02%). Both D. melanogaster and D. ananassae F-element genes exhibit distinct characteristics compared to D-element genes (e.g., larger coding spans, larger introns, more coding exons, and lower codon bias), but these differences are exaggerated in D. ananassae. Compared to D. melanogaster, the codon bias observed in D. ananassae F-element genes can primarily be attributed to mutational biases instead of selection. The 5′ ends of F-element genes in both species are enriched in dimethylation of lysine 4 on histone 3 (H3K4me2), while the coding spans are enriched in H3K9me2. Despite differences in repeat density and gene characteristics, D. ananassae F-element genes show a similar range of expression levels compared to genes in euchromatic domains. This study improves our understanding of how transposons can affect genome size and how genes can function within highly repetitive domains