Activation of the cGAS-STING innate immune response in cells with deficient mitochondrial topoisomerase TOP1MT.

The recognition that cytosolic mitochondrial DNA (mtDNA) activates cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) innate immune signaling has unlocked novel disease mechanisms. Here, an uncharacterized variant predicted to affect TOP1MT function, P193L, was discovered in a family with multiple early onset autoimmune diseases, including Systemic Lupus Erythematosus (SLE). Although there was no previous genetic association between TOP1MT and autoimmune disease, the role of TOP1MT as a regulator of mtDNA led us to investigate whether TOP1MT could mediate the release of mtDNA to the cytosol, where it could then activate the cGAS-STING innate immune pathway known to be activated in SLE and other autoimmune diseases. Through analysis of cells with reduced TOP1MT expression, we show that loss of TOP1MT results in release of mtDNA to the cytosol, which activates the cGAS-STING pathway. We also characterized the P193L variant for its ability to rescue several TOP1MT functions when expressed in TOP1MT knockout cells. We show that the P193L variant is not fully functional, as its re-expression at high levels was unable to rescue mitochondrial respiration deficits, and only showed partial rescue for other functions, including repletion of mtDNA replication following depletion, nucleoid size, steady state mtDNA transcripts levels and mitochondrial morphology. Additionally, expression of P193L at endogenous levels was unable to rescue mtDNA release-mediated cGAS-STING signaling. Overall, we report a link between TOP1MT and mtDNA release leading to cGAS-STING activation. Moreover, we show that the P193L variant has partial loss of function that may contribute to autoimmune disease susceptibility via cGAS-STING mediated activation of the innate immune system.

LRRK2 and Rab10 coordinate macropinocytosis to mediate immunological responses in phagocytes.

Genetic variation in LRRK2 associates with the susceptibility to Parkinson's disease, Crohn's disease, and mycobacteria infection. High expression of LRRK2 and its substrate Rab10 occurs in phagocytic cells in the immune system. In mouse and human primary macrophages, dendritic cells, and microglia-like cells, we find that Rab10 specifically regulates a specialized form of endocytosis known as macropinocytosis, without affecting phagocytosis or clathrin-mediated endocytosis. LRRK2 phosphorylates cytoplasmic PI(3,4,5)P3-positive GTP-Rab10, before EEA1 and Rab5 recruitment to early macropinosomes occurs. Macropinosome cargo in macrophages includes CCR5, CD11b, and MHCII, and LRRK2-phosphorylation of Rab10 potently blocks EHBP1L1-mediated recycling tubules and cargo turnover. EHBP1L1 overexpression competitively inhibits LRRK2-phosphorylation of Rab10, mimicking the effects of LRRK2 kinase inhibition in promoting cargo recycling. Both Rab10 knockdown and LRRK2 kinase inhibition potently suppress the maturation of macropinosome-derived CCR5-loaded signaling endosomes that are critical for CCL5-induced immunological responses that include Akt activation and chemotaxis. These data support a novel signaling axis in the endolysosomal system whereby LRRK2-mediated Rab10 phosphorylation stalls vesicle fast recycling to promote PI3K-Akt immunological responses.

Exploring knowledge gaps and research needs in respiratory therapy: a qualitative description study.

Background: Respiratory therapists (RTs) are expected to stay updated on technology, treatments, research, and best practices to provide high-quality patient care. They must possess the skills to interpret, evaluate, and contribute to evidence-based practices. However, RTs often rely on research from other professions that may not fully address their specific needs, leading to insufficient guidance for their practice. Additionally, there has been no exploration of knowledge gaps and research needs from RTs' perspectives to enhance their practice and patient outcomes. The research questions guiding this study were: (i) what are the perceived practice-oriented knowledge gaps? and (ii) what are the necessary research priorities across the respiratory therapy profession according to experts in respiratory therapy? Methods: A qualitative description study was conducted using semi-structured focus groups with 40 expert RTs from seven areas of practice across Canada. Data was analyzed using qualitative content analysis. Results: We identified four major themes relating to what these experts perceive as the practice-oriented gaps and necessary research priorities across the respiratory therapy profession: 1) system-level impact of RTs, 2) optimizing respiratory therapy practices, 3) scholarship on the respiratory therapy profession and 4) respiratory therapy education. Discussion: The findings establish a fundamental understanding of the current gaps and the specific needs of RTs that require further investigation. Participants strongly emphasized the significance of research priorities that consider the breadth and depth of the respiratory therapy profession, which underscores the complex nature of respiratory therapy and its application in practice. Conclusion: The unique insights garnered from this study highlight the knowledge gaps and research needs specific to RTs. These findings pave the way for further exploration, discourse, and research aimed at understanding the specific contributions and requirements of RTs.

Identification of LRRK2 missense variants in the accelerating medicines partnership Parkinson's disease cohort.

Pathogenic missense variants in the leucine-rich repeat kinase 2 (LRRK2) gene have been identified through linkage analysis in familial Parkinson disease (PD). Subsequently, other missense variants with lower effect sizes on PD risk have emerged, as well as non-coding polymorphisms (e.g. rs76904798) enriched in PD cases in genome-wide association studies. Here we leverage recent whole-genome sequences from the Accelerating Medicines Partnership-Parkinson's Disease (AMP-PD) and the Genome Aggregation (gnomAD) databases to characterize novel missense variants in LRRK2 and explore their relationships with known pathogenic and PD-linked missense variants. Using a computational prediction tool that successfully classifies known pathogenic LRRK2 missense variants, we describe an online web-based resource that catalogs characteristics of over 1200 LRRK2 missense variants of unknown significance. Novel high-pathogenicity scoring variants, some identified exclusively in PD cases, tightly cluster within the ROC-COR-Kinase domains. Structure-function predictions support that some of these variants exert gain-of-function effects with respect to LRRK2 kinase activity. In AMP-PD participants, all p.R1441G carriers (N = 89) are also carriers of the more common PD-linked variant p.M1646T. In addition, nearly all carriers of the PD-linked p.N2081D missense variant are also carriers of the LRRK2 PD-risk variant rs76904798. These results provide a compendium of LRRK2 missense variants and how they associate with one another. While the pathogenic p.G2019S variant is by far the most frequent high-pathogenicity scoring variant, our results suggest that ultra-rare missense variants may have an important cumulative impact in increasing the number of individuals with LRRK2-linked PD.

The interplay between monocytes, α-synuclein and LRRK2 in Parkinson's disease.

The accumulation of aggregated α-synuclein in susceptible neurons in the brain, together with robust activation of nearby myeloid cells, are pathological hallmarks of Parkinson's disease (PD). While microglia represent the dominant type of myeloid cell in the brain, recent genetic and whole-transcriptomic studies have implicated another type of myeloid cell, bone-marrow derived monocytes, in disease risk and progression. Monocytes in circulation harbor high concentrations of the PD-linked enzyme leucine-rich repeat kinase 2 (LRRK2) and respond to both intracellular and extracellular aggregated α-synuclein with a variety of strong pro-inflammatory responses. This review highlights recent findings from studies that functionally characterize monocytes in PD patients, monocytes that infiltrate into cerebrospinal fluid, and emerging analyses of whole myeloid cell populations in the PD-affected brain that include monocyte populations. Central controversies discussed include the relative contribution of monocytes acting in the periphery from those that might engraft in the brain to modify disease risk and progression. We conclude that further investigation into monocyte pathways and responses in PD, especially the discovery of additional markers, transcriptomic signatures, and functional classifications, that better distinguish monocyte lineages and responses in the brain from other types of myeloid cells may reveal points for therapeutic intervention, as well as a better understanding of ongoing inflammation associated with PD.

Scholarly practice in healthcare professions: findings from a scoping review.

Scholarly practitioners are broadly defined as healthcare professionals that address critical practice problems using theory, scientific evidence, and practice-based knowledge. Though scholarly practice is included in most competency frameworks, it is unclear what scholarly practice is, how it develops and how it is operationalized in clinical practice. The aim of this review was to determine what is known about scholarly practice in healthcare professionals. We conducted a scoping review and searched MEDLINE, EMBASE, CINAHL from inception to May 2020. We included papers that explored, described, or defined scholarly practice, scholar or scholarly practitioner, and/or related concepts in healthcare professionals. We included a total of 90 papers. Thirty percent of papers contained an explicit definition of scholarly practice. Conceptualizations of scholarly practice were organized into three themes: the interdependent relationship between scholarship and practice; advancing the profession's field; and core to being a healthcare practitioner. Attributes of scholarly practitioners clustered around five themes: commitment to excellence in practice; collaborative nature; presence of virtuous characteristics; effective communication skills; and adaptive change ethos. No single unified definition of scholarly practice exists within the literature. The variability in terms used to describe scholarly practice suggests that it is an overarching concept rather than a definable entity. There are similarities between scholarly practitioners and knowledge brokers regarding attributes and how scholarly practice is operationalized. Individuals engaged in the teaching, research and/or assessment of scholarly practice should make explicit their definitions and expectations for healthcare professionals.

Dopaminergic neurodegeneration induced by Parkinson's disease-linked G2019S LRRK2 is dependent on kinase and GTPase activity.

Mutations in leucine-rich repeat kinase 2 (LRRK2) are the most common cause of late-onset, autosomal-dominant familial Parkinson's disease (PD). LRRK2 functions as both a kinase and GTPase, and PD-linked mutations are known to influence both enzymatic activities. While PD-linked LRRK2 mutations can commonly induce neuronal damage in culture models, the mechanisms underlying these pathogenic effects remain uncertain. Rodent models containing familial LRRK2 mutations often lack robust PD-like neurodegenerative phenotypes. Here, we develop a robust preclinical model of PD in adult rats induced by the brain delivery of recombinant adenoviral vectors with neuronal-specific expression of human LRRK2 harboring the most common G2019S mutation. In this model, G2019S LRRK2 induces the robust degeneration of substantia nigra dopaminergic neurons, a pathological hallmark of PD. Introduction of a stable kinase-inactive mutation or administration of the selective kinase inhibitor, PF-360, attenuates neurodegeneration induced by G2019S LRRK2. Neuroprotection provided by pharmacological kinase inhibition is mediated by an unusual mechanism involving the robust destabilization of human LRRK2 protein in the brain relative to endogenous LRRK2. Our study further demonstrates that G2019S LRRK2-induced dopaminergic neurodegeneration critically requires normal GTPase activity, as hypothesis-testing mutations that increase GTP hydrolysis or impair GTP-binding activity provide neuroprotection although via distinct mechanisms. Taken together, our data demonstrate that G2019S LRRK2 induces neurodegeneration in vivo via a mechanism that is dependent on kinase and GTPase activity. Our study provides a robust rodent preclinical model of LRRK2-linked PD and nominates kinase inhibition and modulation of GTPase activity as promising disease-modifying therapeutic targets.

What to Teach in Small Animal Veterinary Orthopedics: A Survey of Practicing Veterinarians to Inform Curriculum Development.

Competency-based veterinary education focuses on the knowledge and clinical skills required to generate a productive and confident practitioner. Accurate identification of clinically relevant core competencies enables academic institutions to prioritize which new and foundational information to cover in the limited time available. The goal of this study was to aggregate the opinions of veterinary practitioners about small animal core competencies in veterinary orthopedics. An online 20-question survey was distributed with questions regarding respondent demographics, education, practice type, caseload, involvement in orthopedic procedures, access to referral hospitals, frequency of orthopedic condition presentation and procedure performance, and proposed percent allocation of various orthopedic curriculum topics. Responses were included from 721 respondents, largely first-opinion veterinarians (81%, n = 580/721). The majority (58%; n = 418/721) of respondents performed less than 10% of the orthopedic surgeries themselves and, 37% (n = 266/721) reported never performing orthopedic surgery; of those performing surgeries, 78% (n = 354/455) performed less than six orthopedic procedures monthly. The five most common orthopedic conditions seen included: generalized osteoarthritis, patellar luxation, cranial cruciate ligament disease, hip dysplasia/arthritis, and muscle/tendon injuries. Median respondent scores for the percentage which a topic should comprise in an ideal orthopedic curriculum were 20% each for 'orthopedic exam' and for 'non-surgical orthopedic knowledge', 15% each for 'non-surgical orthopedic skills,' 'orthopedic imaging (radiographs),' and 'surgical orthopedic knowledge,' 10% for 'surgical orthopedic skills,' and 2% for 'advanced orthopedic imaging.' Based on these results, a curriculum focusing on the most clinically relevant orthopedic conditions with an emphasis on diagnosis establishment and non-surgical treatments is proposed.

Experimental Quantification of Halogen⋠⋠⋠Arene van der Waals Contacts.

Crystallographic and computational studies suggest the occurrence of favourable interactions between polarizable arenes and halogen atoms. However, the systematic experimental quantification of halogen⋅⋅⋅arene interactions in solution has been hindered by the large variance in the steric demands of the halogens. Here we have synthesized molecular balances to quantify halogen⋅⋅⋅arene contacts in 17 solvents and solvent mixtures using 1 H NMR spectroscopy. Calculations indicate that favourable halogen⋅⋅⋅arene interactions arise from London dispersion in the gas phase. In contrast, comparison of our experimental measurements with partitioned SAPT0 energies indicate that dispersion is sufficiently attenuated by the solvent that the halogen⋅⋅⋅arene interaction trend was instead aligned with increasing exchange repulsion as the halogen increased in size (ΔGX ⋅⋅⋅Ph =0 to +1.5 kJ mol-1 ). Halogen⋅⋅⋅arene contacts were slightly less disfavoured in solvents with higher solvophobicities and lower polarizabilities, but strikingly, were always less favoured than CH3 ⋅⋅⋅arene contacts (ΔGMe ⋅⋅⋅Ph =0 to -1.4 kJ mol-1 ).

Elevated Urinary Rab10 Phosphorylation in Idiopathic Parkinson Disease.

BACKGROUND: Pathogenic leucine-rich repeat kinase 2 LRRK2 mutations may increase LRRK2 kinase activity and Rab substrate phosphorylation. Genetic association studies link variation in LRRK2 to idiopathic Parkinson disease (iPD) risk. OBJECTIVES: Through measurements of the LRRK2 kinase substrate pT73-Rab10 in urinary extracellular vesicles, this study seeks to understand how LRRK2 kinase activity might change with iPD progression. METHODS: Using an immunoblotting approach validated in LRRK2 transgenic mice, the ratio of pT73-Rab10 to total Rab10 protein was measured in extracellular vesicles from a cross-section of G2019S LRRK2 mutation carriers (N = 45 participants) as well as 485 urine samples from a novel longitudinal cohort of iPD and controls (N = 85 participants). Generalized estimating equations were used to conduct analyses with commonly used clinical scales. RESULTS: Although the G2019S LRRK2 mutation did not increase pT73-Rab10 levels, the ratio of pT73-Rab10 to total Rab10 nominally increased over baseline in iPD urine vesicle samples with time, but did not increase in age-matched controls (1.34-fold vs. 1.05-fold, 95% confidence interval [CI], 0.004-0.56; P = 0.046; Welch's t test). Effect estimates adjusting for sex, age, disease duration, diagnosis, and baseline clinical scores identified increasing total Movement Disorder Society-Sponsored Revision of the Unified (MDS-UPDRS) scores (ß = 0.77; CI, 0.52-1.01; P = 0.0001) with each fold increase of pT73-Rab10 to total Rab10. Lower Montreal Cognitive Assessment (MoCA) score in iPD is also associated with increased pT73-Rab10. CONCLUSIONS: These results provide initial insights into peripheral LRRK2-dependent Rab phosphorylation, measured in biobanked urine, where higher levels of pT73-Rab10 are associated with worse disease progression. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson Movement Disorder Society.

Impact of restricted visitation policies during COVID-19 on critically ill adults, their families, critical care clinicians, and decision-makers: a qualitative interview study.

PURPOSE: During the first wave of the COVID-19 pandemic, restricted visitation policies were enacted at acute care facilities to reduce the spread of COVID-19 and conserve personal protective equipment. In this study, we aimed to describe the impact of restricted visitation policies on critically ill patients, families, critical care clinicians, and decision-makers; highlight the challenges faced in translating these policies into practice; and delineate strategies to mitigate their effects. METHOD: A qualitative description design was used. We conducted semistructured interviews with critically ill adult patients and their family members, critical care clinicians, and decision-makers (i.e., policy makers or enforcers) affected by restricted visitation policies. We transcribed semistructured interviews verbatim and analyzed the transcripts using inductive thematic analysis. RESULTS: Three patients, eight family members, 30 clinicians (13 physicians, 17 nurses from 23 Canadian intensive care units [ICUs]), and three decision-makers participated in interviews. Thematic analysis was used to identify five themes: 1) acceptance of restricted visitation (e.g., accepting with concerns); 2) impact of restricted visitation (e.g., ethical challenges, moral distress, patients dying alone, intensified workload); 3) trust in the healthcare system during the pandemic (e.g., mistrust of clinical team); 4) modes of communication (e.g., communication using virtual platforms); and 5) impact of policy implementation on clinical practice (e.g., frequent changes and inconsistent implementation). CONCLUSIONS: Restricted visitation policies across ICUs during the COVID-19 pandemic negatively affected critically ill patients and their families, critical care clinicians, and decision-makers.

RéSUMé: OBJECTIF: Au cours de la première vague de la pandémie de COVID-19, des politiques de visite restreintes ont été adoptées dans les établissements de soins aigus afin de réduire la propagation de la COVID-19 et d'économiser les équipements de protection individuelle. Dans cette étude, nous avons cherché à décrire l'impact des politiques de visite restreintes sur les patients gravement malades, les familles, les intensivistes et les décideurs, ainsi qu'à souligner les difficultés rencontrées dans la mise en pratique de ces politiques et à définir des stratégies pour en atténuer les effets. MéTHODE: Une méthodologie de description qualitative a été utilisée. Nous avons mené des entretiens semi-structurés avec des patients adultes gravement malades et les membres de leur famille, les intensivistes et les décideurs (c.-à-d. les stratèges ou les responsables de l'application de la loi) touchés par les politiques de visite restreintes. Nous avons transcrit textuellement les entretiens semi-structurés et analysé les transcriptions à l'aide d'une analyse thématique inductive. RéSULTATS: Trois patients, huit membres de leur famille, 30 cliniciens (13 médecins, 17 infirmières de 23 unités de soins intensifs canadiennes) et trois décideurs ont participé à ces entrevues. L'analyse thématique a été utilisée pour identifier cinq thèmes : 1) l'acceptation des visites restreintes (p. ex., accepter avec des préoccupations); 2) l'impact des visites restreintes (p. ex., défis éthiques, détresse morale, patients mourant seuls, charge de travail accrue); 3) la confiance dans le système de santé pendant la pandémie (p. ex., méfiance à l'égard de l'équipe clinique); 4) les modes de communication (p. ex., communication à l'aide de plateformes virtuelles); et 5) l'incidence de la mise en œuvre des politiques sur la pratique clinique (p. ex., changements fréquents et mise en œuvre incohérente). CONCLUSION: Les politiques de visite restreintes dans les unités de soins intensifs pendant la pandémie de COVID-19 ont eu un impact négatif sur les patients gravement malades et leurs familles, les intensivistes et les décideurs.

Evidence-informed consensus statements to guide COVID-19 patient visitation policies: results from a national stakeholder meeting.

PURPOSE: Hospital policies forbidding or limiting families from visiting relatives on the intensive care unit (ICU) has affected patients, families, healthcare professionals, and patient- and family-centered care (PFCC). We sought to refine evidence-informed consensus statements to guide the creation of ICU visitation policies during the current COVID-19 pandemic and future pandemics and to identify barriers and facilitators to their implementation and sustained uptake in Canadian ICUs. METHODS: We created consensus statements from 36 evidence-informed experiences (i.e., impacts on patients, families, healthcare professionals, and PFCC) and 63 evidence-informed strategies (i.e., ways to improve restricted visitation) identified during a modified Delphi process (described elsewhere). Over two half-day virtual meetings on 7 and 8 April 2021, 45 stakeholders (patients, families, researchers, clinicians, decision-makers) discussed and refined these consensus statements. Through qualitative descriptive content analysis, we evaluated the following points for 99 consensus statements: 1) their importance for improving restricted visitation policies; 2) suggested modifications to make them more applicable; and 3) facilitators and barriers to implementing these statements when creating ICU visitation policies. RESULTS: Through discussion, participants identified three areas for improvement: 1) clarity, 2) accessibility, and 3) feasibility. Stakeholders identified several implementation facilitators (clear, flexible, succinct, and prioritized statements available in multiple modes), barriers (perceived lack of flexibility, lack of partnership between government and hospital, change fatigue), and ways to measure and monitor their use (e.g., family satisfaction, qualitative interviews). CONCLUSIONS: Existing guidance on policies that disallowed or restricted visitation in intensive care units were confusing, hard to operationalize, and often lacked supporting evidence. Prioritized, succinct, and clear consensus statements allowing for local adaptability are necessary to guide the creation of ICU visitation policies and to optimize PFCC.

RéSUMé: OBJECTIF: Les politiques hospitalières interdisant ou limitant les visites des familles à des proches à l'unité de soins intensifs (USI) ont affecté les patients, les familles, les professionnels de la santé et les soins centrés sur le patient et la famille (SCPF). Nous avons cherché à affiner les déclarations de consensus fondées sur des données probantes afin de guider la création de politiques de visite aux soins intensifs pendant la pandémie actuelle de COVID-19 et les pandémies futures, et dans le but d'identifier les obstacles et les critères facilitants à leur mise en œuvre et à leur adoption répandue dans les unités de soins intensifs canadiennes. MéTHODE: Nous avons créé des déclarations de consensus à partir de 36 expériences fondées sur des données probantes (c.-à-d. impacts sur les patients, les familles, les professionnels de la santé et les SCPF) et 63 stratégies fondées sur des données probantes (c.-à-d. moyens d'améliorer les restrictions des visites) identifiées au cours d'un processus Delphi modifié (décrit ailleurs). Au cours de deux réunions virtuelles d'une demi-journée tenues les 7 et 8 avril 2021, 45 intervenants (patients, familles, chercheurs, cliniciens, décideurs) ont discuté et affiné ces déclarations de consensus. Grâce à une analyse descriptive qualitative du contenu, nous avons évalué les points suivants pour 99 déclarations de consensus : 1) leur importance pour l'amélioration des politiques de restriction des visites; 2) les modifications suggérées pour les rendre plus applicables; et 3) les critères facilitants et les obstacles à la mise en œuvre de ces déclarations lors de la création de politiques de visite aux soins intensifs. RéSULTATS: En discutant, les participants ont identifié trois domaines à améliorer : 1) la clarté, 2) l'accessibilité et 3) la faisabilité. Les intervenants ont identifié plusieurs critères facilitants à la mise en œuvre (énoncés clairs, flexibles, succincts et hiérarchisés disponibles dans plusieurs modes), des obstacles (manque perçu de flexibilité, manque de partenariat entre le gouvernement et l'hôpital, fatigue du changement) et des moyens de mesurer et de surveiller leur utilisation (p. ex., satisfaction des familles, entrevues qualitatives). CONCLUSION: Les directives existantes sur les politiques qui interdisaient ou limitaient les visites dans les unités de soins intensifs étaient déroutantes, difficiles à mettre en oeuvre et manquaient souvent de données probantes à l'appui. Des déclarations de consensus hiérarchisées, succinctes et claires permettant une adaptabilité locale sont nécessaires pour guider la création de politiques de visite en soins intensifs et pour optimiser les soins centrés sur le patient et la famille.

Exploration of Immersive Virtual Reality in Teaching Veterinary Orthopedics.

The COVID-19 pandemic has catalyzed the use of novel teaching modalities to enhance the provision of remote veterinary education. In this study, we describe the use of immersive virtual reality (iVR) as a teaching aid for veterinary medicine students during their orthopedics clinical rotation. Student sentiments were assessed using voluntary electronic surveys taken by veterinary students before and after the rotation. The most noteworthy benefits students reported were improved engagement with the course content, information retention, radiographic interpretation, and clinical reasoning skills. Obstacles encountered during the initial stages of the program included financial and temporal investment in equipment and content development, technical troubleshooting, and motion sickness. Though it is unlikely that iVR will ever fully replace hands-on learning experiences, it presents an educational opportunity to supplement traditional learning methods, motivate students, and fill information gaps. As iVR technology continues to evolve and improve, potential applications in the veterinary curriculum grow, making the modality's use progressively more advantageous. Although this study describes its application in an orthopedic setting, the versatility of the iVR modality lends the potential for it to be implemented in a number of clinical and didactic settings.

Heterogeneity in α-synuclein fibril activity correlates to disease phenotypes in Lewy body dementia.

α-Synuclein aggregation underlies pathological changes in Lewy body dementia. Recent studies highlight structural variabilities associated with α-synuclein aggregates in patient populations. Here, we develop a quantitative real-time quaking-induced conversion (qRT-QuIC) assay to measure permissive α-synuclein fibril-templating activity in tissues and cerebrospinal fluid (CSF). The assay is anchored through reference panels of stabilized ultra-short fibril particles. In humanized α-synuclein transgenic mice, qRT-QuIC identifies differential levels of fibril activity across the brain months before the deposition of phosphorylated α-synuclein in susceptible neurons. α-Synuclein fibril activity in cortical brain extracts from dementia with Lewy bodies (DLB) correlates with activity in matched ventricular CSF. Elevated α-synuclein fibril activity in CSF corresponds to reduced survival in DLB. α-Synuclein fibril particles amplified from cases with high fibril activity show superior templating in the formation of new inclusions in neurons relative to the same number of fibril particles amplified from DLB cases with low fibril activity. Our results highlight a previously unknown broad heterogeneity of fibril-templating activities in DLB that may contribute to disease phenotypes. We predict that quantitative assessments of fibril activities in CSF that correlate to fibril activities in brain tissue will help stratify patient populations as well as measure therapeutic responses to facilitate the development of α-synuclein-targeted therapeutics.

Age-associated insolubility of parkin in human midbrain is linked to redox balance and sequestration of reactive dopamine metabolites.

The mechanisms by which parkin protects the adult human brain from Parkinson disease remain incompletely understood. We hypothesized that parkin cysteines participate in redox reactions and that these are reflected in its posttranslational modifications. We found that in post mortem human brain, including in the Substantia nigra, parkin is largely insoluble after age 40 years; this transition is linked to its oxidation, such as at residues Cys95 and Cys253. In mice, oxidative stress induces posttranslational modifications of parkin cysteines that lower its solubility in vivo. Similarly, oxidation of recombinant parkin by hydrogen peroxide (H2O2) promotes its insolubility and aggregate formation, and in exchange leads to the reduction of H2O2. This thiol-based redox activity is diminished by parkin point mutants, e.g., p.C431F and p.G328E. In prkn-null mice, H2O2 levels are increased under oxidative stress conditions, such as acutely by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine toxin exposure or chronically due to a second, genetic hit; H2O2 levels are also significantly increased in parkin-deficient human brain. In dopamine toxicity studies, wild-type parkin, but not disease-linked mutants, protects human dopaminergic cells, in part through lowering H2O2. Parkin also neutralizes reactive, electrophilic dopamine metabolites via adduct formation, which occurs foremost at the primate-specific residue Cys95. Further, wild-type but not p.C95A-mutant parkin augments melanin formation in vitro. By probing sections of adult, human midbrain from control individuals with epitope-mapped, monoclonal antibodies, we found specific and robust parkin reactivity that co-localizes with neuromelanin pigment, frequently within LAMP-3/CD63+ lysosomes. We conclude that oxidative modifications of parkin cysteines are associated with protective outcomes, which include the reduction of H2O2, conjugation of reactive dopamine metabolites, sequestration of radicals within insoluble aggregates, and increased melanin formation. The loss of these complementary redox effects may augment oxidative stress during ageing in dopamine-producing cells of mutant PRKN allele carriers, thereby enhancing the risk of Parkinson's-linked neurodegeneration.

Genetic and Environmental Factors in Parkinson's Disease Converge on Immune Function and Inflammation.

Idiopathic Parkinson's disease (iPD) is a movement disorder characterized by the degeneration of dopaminergic neurons and aggregation of the protein α-synuclein. Patients with iPD vary in age of symptom onset, rate of progression, severity of motor and non-motor symptoms, and extent of central and peripheral inflammation. Genetic and environmental factors are believed to act synergistically in iPD pathogenesis. We propose that environmental factors (pesticides and infections) increase the risk for iPD via the immune system and that the role of PD risk genes in immune cells is worthy of investigation. This review highlights the major PD-relevant genes expressed in immune cells and key environmental factors that activate immune cells and, alone or in combination with other factors, may contribute to iPD pathogenesis. By reviewing these interactions, we seek to enable the future development of immunomodulatory approaches to prevent or delay onset of iPD. © 2020 International Parkinson and Movement Disorder Society.

Restricted visitation policies in acute care settings during the COVID-19 pandemic: a scoping review.

BACKGROUND: Restricted visitation policies in acute care settings because of the COVID-19 pandemic have negative consequences. The objective of this scoping review is to identify impacts of restricted visitation policies in acute care settings, and describe perspectives and mitigation approaches among patients, families, and healthcare professionals. METHODS: We searched Medline, Embase, PsycINFO, Healthstar, CINAHL, Cochrane Central Register of Controlled Trials on January 01/2021, unrestricted, for published primary research records reporting any study design. We included secondary (e.g., reviews) and non-research records (e.g., commentaries), and performed manual searches in web-based resources. We excluded records that did not report primary data. Two reviewers independently abstracted data in duplicate. RESULTS: Of 7810 citations, we included 155 records. Sixty-six records (43%) were primary research; 29 (44%) case reports or case series, and 26 (39%) cohort studies; 21 (14%) were literature reviews and 8 (5%) were expert recommendations; 54 (35%) were commentary, editorial, or opinion pieces. Restricted visitation policies impacted coping and daily function (n = 31, 20%) and mental health outcomes (n = 29, 19%) of patients, families, and healthcare professionals. Participants described a need for coping and support (n = 107, 69%), connection and communication (n = 107, 69%), and awareness of state of well-being (n = 101, 65%). Eighty-seven approaches to mitigate impact of restricted visitation were identified, targeting families (n = 61, 70%), patients (n = 51, 59%), and healthcare professionals (n = 40, 46%). CONCLUSIONS: Patients, families, and healthcare professionals were impacted by restricted visitation polices in acute care settings during COVID-19. The consequences of this approach on patients and families are understudied and warrant evaluation of approaches to mitigate their impact. Future pandemic policy development should include the perspectives of patients, families, and healthcare professionals. TRIAL REGISTRATION: The review was registered on PROSPERO (CRD42020221662) and a protocol peer-reviewed prior to data extraction.

An environmental scan of visitation policies in Canadian intensive care units during the first wave of the COVID-19 pandemic.

PURPOSE: In response to the rapid spread of SARS-CoV-2, hospitals in Canada enacted temporary visitor restrictions to limit the spread of COVID-19 and preserve personal protective equipment supplies. This study describes the extent, variation, and fluctuation of Canadian adult intensive care unit (ICU) visitation policies before and during the first wave of the COVID-19 pandemic. METHODS: We conducted an environmental scan of Canadian hospital visitation policies throughout the first wave of the pandemic. We conducted a two-phased study analyzing both quantitative and qualitative data. RESULTS: We collected 257 documents with reference to visitation policies (preCOVID, 101 [39%]; midCOVID, 71 [28%]; and lateCOVID, 85 [33%]). Of these 257 documents, 38 (15%) were ICU-specific and 70 (27%) referenced the ICU. Most policies during the midCOVID/lateCOVID pandemic period allowed no visitors with specific exceptions (e.g., end-of-life). Framework analysis revealed five overarching themes: 1) reasons for restricted visitation policies; 2) visitation policies and expectations; 3) exceptions to visitation policy; 4) patient and family-centred care; and 5) communication and transparency. CONCLUSIONS: During the first wave of the COVID-19 pandemic, most Canadian hospitals had public-facing visitor restriction policies with specific exception categories, most commonly for patients at end-of-life, patients requiring assistance, or COVID-19 positive patients (varying from not allowed to case-by-case). Further studies are needed to understand the consistency with which visitation policies were operationalized and how they may have impacted patient- and family-centred care.

RéSUMé: OBJECTIF: En réponse à la propagation rapide du SRAS-CoV-2, les hôpitaux du Canada ont adopté des restrictions temporaires pour les visites afin de limiter la propagation de la COVID-19 et de préserver les stocks d'équipements de protection individuelle. Cette étude décrit l'ampleur, les variations et fluctuations des politiques canadiennes concernant les visites aux unités de soins intensifs (USI) pour adultes avant et pendant la première vague de la pandémie de COVID-19. MéTHODE: Nous avons réalisé une étude de milieu des politiques hospitalières canadiennes concernant les visites tout au long de la première vague de la pandémie. Nous avons mené une étude en deux phases analysant des données quantitatives et qualitatives. RéSULTATS: Nous avons recueilli 257 documents faisant référence aux politiques de visites (pré-COVID, 101 [39 %]; mid-COVID, 71 [28 %]; et COVID-tardif, 85 [33 %]). Sur ces 257 documents, 38 (15 %) étaient spécifiques aux USI et 70 (27 %) faisaient référence aux USI. La plupart des politiques au cours de la période pandémique mid-COVID/COVID-tardif ne permettaient aucune visite sauf exception spécifique (p. ex., fin de vie). L'analyse du cadre a révélé cinq thèmes généraux : 1) les raisons des restrictions des politiques de visites; 2) les politiques et attentes en matière de visites; 3) les exceptions aux politiques de visites; 4) les soins aux patients et centrés sur la famille; et 5) la communication et la transparence. CONCLUSION: Au cours de la première vague de la pandémie de COVID-19, la plupart des hôpitaux canadiens avaient des politiques de restriction des visites s'appliquant au public avec des catégories d'exception spécifiques, le plus souvent pour les patients en fin de vie, les patients nécessitant de l'aide ou les patients COVID-positifs (variant d'une interdiction au cas par cas). D'autres études sont nécessaires pour comprendre l'uniformité avec laquelle les politiques de visites ont été mises en œuvre et comment elles ont pu avoir une incidence sur les soins centrés sur le patient et la famille.

Exploring the professionalization of respiratory therapy in Canada.

INTRODUCTION: A recurrent challenge facing respiratory therapists (RTs) is their legitimacy as professionals. RTs are often referred to as technologists, vocationalists, or technicians and must often justify their status as full professionals rather than "professional technicians". There is currently little exploration of what it means to be a profession and the process of professionalization in respiratory therapy. APPROACH: Drawing from sociological theory, the purpose of this paper is to discuss the professionalization of respiratory therapy in Canada using Andrew Abbott's theory, the "system of professions". We will use this theory as a lens to propose areas of consideration for professional development regarding two pervasive themes in the respiratory therapy community, RTs' specialized body of knowledge and professional autonomy. FINDINGS: Abstract knowledge is believed to be essential in the evolution from occupation to profession and is valuable to a profession in three ways: it can influence the profession's legitimacy, it can be used for conducting research, and it promotes higher education. RTs possess jurisdictional professional autonomy within Canada. The privilege of self-regulation allows RTs to act according to their knowledge and judgement without direct oversight from other professions. CONCLUSION: Based on Abbott's theoretical position, RTs can rightly justify their position as professionals. However, RTs need to acknowledge that professionalization is a dynamic and continuous process that requires creative changes to innovate within the profession and support future efforts to reinforce their position as professionals. Throughout this paper, we offer suggestions for how RTs can contribute to the ongoing professionalization of respiratory therapy.

The Respiratory Therapy Practice-Based Outcomes Initiative (RT-PBOI): Developing a framework to explore the value added by respiratory therapists to health care in Alberta.

BACKGROUND: There exists a political imperative to have access to data that meets the needs of health care administrators, governments, and funding bodies to support evidence-informed decision making. It is incumbent upon respiratory therapists to examine how they can deliver the highest-quality patient care, but also that they add value to health systems that ensure the benefits of health innovations are shared equitably among all members of our communities. PURPOSE: To explore the perceived value contributed by the respiratory therapy profession to health care and the health care system in the Province of Alberta at patient, team, and system levels. RESEARCH METHODS: An interpretive descriptive approach was adopted, including the formation of a description and exploration of possible associations, relationships, and patterns within a field of practice. CONCLUSIONS: The qualitative data analysis uncovered a framework that could inform research efforts of the respiratory therapy community in a way that contributes to the proposed mechanisms by which the profession generates value for the organization and patients. The RT-PBOI Conceptual Model identified five key concepts relating to the value contributed by respiratory therapists to health care: technical skills, practice across settings, strategic expertise, tools that leverage capacity, and growing value into the future.