Rotavirus core shell protein sites that regulate intra-particle polymerase activity.

IMPORTANCE: Rotaviruses are important causes of severe gastroenteritis in young children. A characteristic feature of rotaviruses is that they copy ribonucleic acid (RNA) inside of the viral particle. In fact, the viral polymerase (VP1) only functions when it is connected to the viral inner core shell protein (VP2). Here, we employed a biochemical assay to identify which sites of VP2 are critical for regulating VP1 activity. Specifically, we engineered VP2 proteins to contain amino acid changes at structurally defined sites and assayed them for their capacity to support VP1 function in a test tube. Through this work, we were able to identify several VP2 residues that appeared to regulate the activity of the polymerase, positively and negatively. These results are important because they help explain how rotavirus synthesizes its RNA while inside of particles and they identify targets for the future rational design of drugs to prevent rotavirus disease.

Liquid Transmission Electron Microscopy for Probing Collagen Biomineralization.

Collagen biomineralization is fundamental to hard tissue assembly. While studied extensively, collagen mineralization processes are not fully understood, with the majority of theories derived from electron microscopy (EM) under static, dehydrated, or frozen conditions, unlike the liquid phase environment where mineralization occurs. Herein, novel liquid transmission EM (TEM) strategies are presented, in which collagen mineralization was explored in liquid for the first time via TEM. Custom thin-film enclosures were employed to visualize the mineralization of reconstituted collagen fibrils in a calcium phosphate and polyaspartic acid solution to promote intrafibrillar mineralization. TEM highlighted that at early time points precursor mineral particles attached to collagen and progressed to crystalline mineral platelets aligned with fibrils at later time points. This aligns with observations from other techniques and validates the liquid TEM approach. This work provides a new liquid imaging approach for exploring collagen biomineralization, advancing toward understanding disease pathogenesis and remineralization strategies for hard tissues.

Strategies to guide the successful implementation of deprescribing in community practice: Lessons learned from the front line.

Background: Sustainable implementation of new professional services into clinical practice can be difficult. In 2019, a population-wide initiative called SaferMedsNL was implemented across the province of Newfoundland and Labrador (NL), to promote appropriate medication use. Two evidence-based interventions were adapted to the context of NL to promote deprescribing of proton pump inhibitors and sedatives. The objective of this study was to identify and prioritize which actions supported the implementation of deprescribing in community practice for pharmacists, physicians and nurse practitioners across the province. Methods: Community pharmacists, physicians and nurse practitioners were invited to participate in virtual focus groups. Nominal Group Technique was used to elicit responses to the question: "What actions support the implementation of deprescribing into the daily workflow of your practice?" Participants prioritized actions within each group while thematic analysis permitted comparison across groups. Results: Five focus groups were held in fall 2020 involving pharmacists (n = 11), physicians (n = 7) and nurse practitioners (n = 4). Participants worked in rural (n = 10) and urban (n = 12) settings. The different groups agreed on what the top 5 actions were, with the top 5 receiving 68% of the scores: (1) providing patient education, (2) allocating time and resources, (3) building interprofessional collaboration and communication, (4) fostering patient relationships and (5) aligning with public awareness strategies. Conclusion: Pharmacists, physicians and nurse practitioners identified similar actions that supported implementing evidence-based deprescribing into routine clinical practice. Sharing these strategies may help others embed deprescribing into daily practice and assist the uptake of medication appropriateness initiatives by front-line providers. Can Pharm J (Ott) 2024;157:xx-xx.

Barriers and enablers to testing for hepatitis C virus infection in people who inject drugs - a scoping review of the qualitative evidence.

BACKGROUND: Injection drug use is the primary mode of transmission of hepatitis C virus (HCV) infection in the developed world and guidelines recommend screening individuals with current or history of injection drug use for HCV; however, the majority of those living with HCV in Canada are not aware of their positive status. This low level of HCV status awareness suggests that screening is not effective with current testing strategies. The aim of this review is to determine what barriers and enablers people who inject drugs (PWID) experience surrounding testing for HCV to help inform the development of an engaging testing strategy. METHODS: Comprehensive literature searches were conducted using Medline, Embase and CINAHL in February 2021. Included studies investigated the barriers and enablers to testing for HCV in PWID and the experiences of PWID in testing for HCV. Studies were included if they were qualitative or mixed-methods design, involved people with current injection drug use or those with a history of injecting drugs, and were written in the English language. Studies were compared and common themes were coded and analyzed. RESULTS: The literature search resulted in 1554 citations and ultimately nine studies were included. Common barriers included self-perception of low risk for HCV, fear of diagnosis, stigma associated with IV drug use and HCV, antipathy in relation to mainstream health care services, limited knowledge about HCV, lack of rapport with provider, lack of motivation or competing priority of drug use, and limited awareness of new treatment options. Common enablers to testing included increasing awareness of HCV testing and treatment and providing positive narratives around HCV care, positive rapport with provider, accessible testing options and individualized care. CONCLUSION: While there has been some qualitative research on barriers and enablers to testing for HCV in PWID more research is needed to focus on this research question as a primary objective in order to provide more understanding from the participant's perspective.

Structural Insights of the SARS-CoV-2 Nucleocapsid Protein: Implications for the Inner-workings of Rapid Antigen Tests.

The nucleocapsid (N) protein is an abundant component of SARS-CoV-2 and a key analyte for lateral-flow rapid antigen tests. Here, we present new structural insights for the SARS-CoV-2 N protein using cryo-electron microscopy (EM) and molecular modeling tools. Epitope mapping based on structural data supported host-immune interactions in the C-terminal portion of the protein, while other regions revealed protein-protein interaction sites. Complementary modeling results suggested that N protein structures from known variants of concern (VOC) are nearly 100% conserved at specific antibody-binding sites. Collectively, these results suggest that rapid tests that target the nucleocapsid C-terminal domain should have similar accuracy across all VOCs. In addition, our combined structural modeling workflow may guide the design of immune therapies to counter viral processes as we plan for future variants and pandemics.

Target users' acceptance of a pharmacist-led prescribing service for pre-exposure prophylaxis (PrEP) for human immunodeficiency virus (HIV).

Background: Pre-exposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) is a highly effective way to reduce virus transmission. There have been increasing calls to improve access to PrEP in Canada. One way to improve access is by having more prescribers available. The objective of this study was to determine target users' acceptance of a PrEP-prescribing service by pharmacists in Nova Scotia. Methods: A triangulation, mixed-methods study was conducted consisting of an online survey and qualitative interviews underpinned by the Theoretical Framework of Acceptability (TFA) constructs (affective attitude, burden, ethicality, intervention coherence, opportunity cost, perceived effectiveness and self-efficacy). Participants were those eligible for PrEP in Nova Scotia (men who have sex with men or transgender women, persons who inject drugs and HIV-negative individuals in serodiscordant relationships). Descriptive statistics and ordinal logistic regression were used to analyze survey data. Interview data were deductively coded according to each TFA construct and then inductively coded to determine themes within each construct. Results: A total of 148 responses were captured by the survey, and 15 participants were interviewed. Participants supported pharmacists' prescribing PrEP across all TFA constructs from both survey and interview data. Identified concerns related to pharmacists' abilities to order and view lab results, pharmacists' knowledge and skills for sexual health and the potential for experiencing stigma within pharmacy settings. Conclusion: A pharmacist-led PrEP-prescribing service is acceptable to eligible populations in Nova Scotia. The feasibility of PrEP prescribing by pharmacists should be pursued as an intervention to increase access to PrEP.

Community pharmacists' acceptance of prescribing pre-exposure prophylaxis (PrEP) for human immunodeficiency virus (HIV).

Background: Pre-exposure prophylaxis (PrEP) for human immunodeficiency virus (HIV) prevention is highly effective. Pharmacists can increase PrEP accessibility through pharmacist prescribing. This study aimed to determine pharmacists' acceptance of a pharmacist PrEP prescribing service in Nova Scotia. Methods: A triangulation mixed methods study consisting of an online survey and qualitative interviews was conducted with Nova Scotia community pharmacists. The survey questionnaire and qualitative interview guide were underpinned by the 7 constructs of the Theoretical Framework of Acceptability (affective attitude, burden, ethicality, opportunity costs, intervention coherence, perceived effectiveness and self-efficacy). Survey data were analyzed descriptively and with ordinal logistic regression to determine associations between variables. Interview transcripts were deductively coded according to the same constructs and then inductively coded to identify themes within each construct. Results: A total of 214 community pharmacists completed the survey, and 19 completed the interview. Pharmacists were positive about PrEP prescribing in the constructs of affective attitude (improved access), ethicality (benefits communities), intervention coherence (practice alignment) and self-efficacy (role). Pharmacists expressed concerns about burden (increased workload), opportunity costs (time to provide the service) and perceived effectiveness (education/training, public awareness, laboratory test ordering and reimbursement). Conclusion: A PrEP prescribing service has mixed acceptability to Nova Scotia pharmacists yet represents a model of service delivery to increase PrEP access to underserved populations. Future service development must consider pharmacists' workload, education and training as well as factors relating to laboratory test ordering and reimbursement.

High-Resolution Imaging of Human Cancer Proteins Using Microprocessor Materials.

Mutations in tumor suppressor genes, such as Tumor Protein 53 (TP53), are heavily implicated in aggressive cancers giving rise to gain- and loss-of-function phenotypes. While individual domains of the p53 protein have been studied extensively, structural information for full-length p53 remains incomplete. Functionalized microprocessor chips (microchips) with properties amenable to electron microscopy permitted us to visualize complete p53 assemblies for the first time. The new structures revealed p53 in an inactive dimeric state independent of DNA binding. Residues located at the protein-protein interface corresponded with modification sites in cancer-related hot spots. Changes in these regions may amplify the toxic effects of clinical mutations. Taken together, these results contribute advances in technology and imaging approaches to decode native protein models in different states of activation.

Automated Tools to Advance High-Resolution Imaging in Liquid.

Liquid-electron microscopy (EM), the room-temperature correlate to cryo-EM, is a rapidly growing field providing high-resolution insights of macromolecules in solution. Here, we describe how liquid-EM experiments can incorporate automated tools to propel the field to new heights. We demonstrate fresh workflows for specimen preparation, data collection, and computing processes to assess biological structures in liquid. Adeno-associated virus (AAV) and the SARS-CoV-2 nucleocapsid (N) were used as model systems to highlight the technical advances. These complexes were selected based on their major differences in size and natural symmetry. AAV is a highly symmetric, icosahedral assembly with a particle diameter of ~25 nm. At the other end of the spectrum, N protein is an asymmetric monomer or dimer with dimensions of approximately 5­7 nm, depending upon its oligomerization state. Equally important, both AAV and N protein are popular subjects in biomedical research due to their high value in vaccine development and therapeutic efforts against COVID-19. Overall, we demonstrate how automated practices in liquid-EM can be used to decode molecules of interest for human health and disease.

Complete Models of p53 Better Inform the Impact of Hotspot Mutations.

Mutations in tumor suppressor genes often lead to cancerous phenotypes. Current treatments leverage signaling pathways that are often compromised by disease-derived deficiencies in tumor suppressors. P53 falls into this category as genetic mutations lead to physical changes in the protein that impact multiple cellular pathways. Here, we show the first complete structural models of mutated p53 to reveal how hotspot mutations physically deviate from the wild-type protein. We employed a recently determined structure for the p53 monomer to map seven frequent clinical mutations using computational modeling approaches. Results showed that missense mutations often changed the conformational structure of p53 in the DNA-binding site along with its electrostatic surface charges. We posit these changes may amplify the toxic effects of these hotspot mutations by destabilizing an important zinc ion coordination region in p53 to impede proper DNA interactions. These results highlight the imperative need for new studies on patient-derived proteins that may assist in redesigning structure-informed targeted therapies.

Microchip-Based Structure Determination of Disease-Relevant p53.

The tumor suppressor protein TP53 (p53) plays a multifaceted role in all cells of the human body. Mutations in the TP53 gene are often involved in cancer induction and disease progression. Despite its important role in health and development, structural information for p53 remains incomplete. Here, we present a microchip-based technology to facilitate structural studies of p53 assemblies derived from human cancer cells. These devices do not introduce foreign sequences to the p53 gene and maintain naturally occurring post-translational modifications. Using cryo-electron microscopy, structures for the p53 monomer (∼50 kDa) and tetramer (∼200 kDa) were resolved to ∼4.8 and ∼7 Å, respectively. These structures revealed new insights for flexible regions of p53 along with biologically relevant ubiquitination sites. Collectively, the convergence of nanotechnology tools and structural imaging builds a strong framework to understand the oncogenic impact of p53 in human tissues.

Expanding access to HIV testing through Canadian community pharmacies: findings from the APPROACH study.

BACKGROUND: There is a need for acceptable and feasible HIV testing options to ensure people living with HIV know their status so they can access care. Pharmacist-provided HIV point-of-care testing (POCT) may overcome testing barriers, including privacy concerns, testing wait times, and improve accessibility. In the APPROACH study, we aimed to develop and assess an HIV POCT program in community pharmacies for future scale up and evaluation. This paper describes the program uptake, participant and pharmacist experiences, and implementation factors. METHODS: A pharmacist-provided HIV POCT program was offered in 4 pharmacies in two Canadian provinces. A mixed methods design incorporated self-report questionnaire data, participant telephone interviews, pharmacist focus groups, workload analysis, and situational analysis to assess the uptake, acceptability and feasibility of the HIV POCT program. RESULTS: Over the 6-month pilot, 123 HIV tests were performed. One new case of HIV was identified; this participant was linked with confirmatory testing and HIV care. Participants were predominantly male (76%), with a mean age of 35 years. This was the first HIV test for 27% participants, and 75% were at moderate to very high risk of undiagnosed HIV infection, by Denver HIV Risk Score. Questionnaires and telephone interviews showed participants were very satisfied with the program; 99% agreed HIV POCT should be routinely offered in pharmacies and 78% were willing to pay for the service. Participants felt the pharmacy was convenient, discreet, and that the pharmacist was supportive and provided education about how to reduce their future risk. Pharmacists felt prepared, confident, and expressed professional satisfaction with offering HIV POCT. Community and public health supports, clear linkage to care plans to refer participants with positive HIV POCT results, and provision of counselling tools were important enabling factors for the program. Pharmacist remuneration, integration with existing healthcare systems, and support for ongoing promotion of HIV POCT availability in pharmacies were identified as needs for future scale-up and sustainability. CONCLUSIONS: A successful model of pharmacy-based POCT, including linkage to care, was developed. Further research is needed to determine the effectiveness and cost-effectiveness of this approach in finding new diagnoses and linking them with care. TRIAL REGISTRATION: Retrospectively registered with clinicaltrials.gov (NCT03210701) on July 6, 2017.

Liquid-Cell Electron Tomography of Biological Systems.

Liquid-cell electron microscopy is a rapidly growing field in the imaging domain. While real-time observations are readily available to analyze materials and biological systems, these measurementshave been limited to the two-dimensional (2-D) image plane. Here, we introduce an exciting technical advance to image materials in 3-D while enclosed in liquid. The development of liquid-cell electron tomography permitted us to observe and quantify host-pathogen interactions in solution while contained in the vacuum system of the electron microscope. In doing so, we demonstrate new insights for the rules of engagement involving a unique bacteriophage and its host bacterium. A deeper analysis of the genetic content of the phage pathogens revealed structural features of the infectious units while introducing a new paradigm for host interactions. Overall, we demonstrate a technological opportunity to elevate research efforts for in situ imaging while providing a new level of dimensionality beyond the current state of the field.

Cryo-EM-On-a-Chip: Custom-Designed Substrates for the 3D Analysis of Macromolecules.

The fight against human disease requires a multidisciplinary scientific approach. Applying tools from seemingly unrelated areas, such as materials science and molecular biology, researchers can overcome long-standing challenges to improve knowledge of molecular pathologies. Here, custom-designed substrates composed of silicon nitride (SiN) are used to study the 3D attributes of tumor suppressor proteins that function in DNA repair events. New on-chip preparation strategies enable the isolation of native protein complexes from human cancer cells. Combined techniques of cryo-electron microscopy (EM) and molecular modeling reveal a new modified form of the p53 tumor suppressor present in aggressive glioblastoma multiforme cancer cells. Taken together, the findings provide a radical new design for cryo-EM substrates to evaluate the structures of disease-related macromolecules.

Characteristics and outcomes of antiretroviral-treated HIV-HBV co-infected patients in Canada?

BACKGROUND: Hepatitis B (HBV) and Human Immunodeficiency Virus (HIV) share common risk factors for exposure. Co-infected patients have an increased liver-related mortality risk and may have accelerated HIV progression. The epidemiology and demographic characteristics of HIV-HBV co-infection in Canada remain poorly defined. We compared the demographic and clinical characteristics and factors associated with advanced hepatic fibrosis between HIV and HIV-HBV co-infected patients. METHODS: A retrospective cohort analysis was conducted using data from the Canadian Observational Cohort (CANOC) Collaboration, including eight sites from British Columbia, Quebec, and Ontario. Eligible participants were HIV-infected patients who initiated combination ARV between January 1, 2000 and December 14, 2014. Demographic and clinical characteristics were compared between HIV-HBV co-infected and HIV-infected groups using chi-square or Fisher exact tests for categorical variables, and Wilcoxon's Rank Sum test for continuous variables. Liver fibrosis was estimated by the AST to Platelet Ratio Index (APRI). RESULTS: HBV status and APRI values were available for 2419 cohort participants. 199 (8%) were HBV co-infected. Compared to HIV-infected participants, HIV-HBV co-infected participants were more likely to use injection drugs (28% vs. 21%, p = 0.03) and be HCV-positive (31%, vs. 23%, p = 0.02). HIV-HBV co-infected participants had lower baseline CD4 T cell counts (188 cells/mm3, IQR: 120-360) compared to 235 cells/mm3 in HIV-infected participants (IQR: 85-294) (p = 0.0002) and higher baseline median APRI scores (0.50 vs. 0.37, p < 0.0001). This difference in APRI was no longer clinically significant at follow-up (0.32 vs. 0.30, p = 0.03). HIV-HBV co-infected participants had a higher mortality rate compared to HIV-infected participants (11% vs. 7%, p = 0.02). CONCLUSION: The prevalence, demographic and clinical characteristics of the HIV-HBV co-infected population in Canada is described. HIV-HBV co-infected patients have higher mortality, more advanced CD4 T cell depletion, and liver fibrosis that improves in conjunction with ARV therapy. The high prevalence of unknown HBV status demonstrates a need for increased screening among HIV-infected patients in Canada.

Patient satisfaction with chronic HIV care provided through an innovative pharmacist/nurse-managed clinic and a multidisciplinary clinic.

BACKGROUND: Pharmacist/nurse-led clinics are an established model for many chronic diseases but not yet for HIV. At our centre, patients with HIV are seen by a multidisciplinary team (physician, nurse, pharmacist, social worker) at least yearly. Some attend an HIV-specialist pharmacist/nurse clinic (or "nonphysician clinic," NPC) for alternate biannual visits. Our objective was to assess patient satisfaction with care received through both clinics. METHODS: The Patient Satisfaction Survey for HIV Ambulatory Care (assesses satisfaction with access to care, clinic visits and quality of care) was administered by telephone to adults who attended either clinic between January and July 2014. Descriptive statistics described patient characteristics and satisfaction scores. Fisher's exact test compared satisfaction scores between the NPC and multidisciplinary clinic (MDC). Multivariate logistic regression examined associations between overall satisfaction with care and clinic type and patient characteristics (e.g., age, disease duration). RESULTS: Respondents were very satisfied with the overall quality of HIV care in both the NPC and MDC (89% vs 93%, respectively, p = 0.6). Patients from both clinics expressed satisfaction with access to care, treatment plan input, their provider's knowledge of the newest developments in HIV care and explanation of medication side effects, with no significant differences noted. Significantly more MDC patients reported being asked about housing/finances, alcohol/drug use and whether they needed help disclosing their status. Patient characteristics were not significantly associated with satisfaction with overall quality of care. CONCLUSION: Patients are satisfied with both clinics, supporting NPC as an innovative model for chronic HIV care. Comparison of outcomes between clinics is needed to ensure high-quality care.