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1.
Vet Res ; 55(1): 62, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750594

RESUMO

The first case of CWD in a Norwegian red deer was detected by a routine ELISA test and confirmed by western blotting and immunohistochemistry in the brain stem of the animal. Two different western blotting tests were conducted independently in two different laboratories, showing that the red deer glycoprofile was different from the Norwegian CWD reindeer and CWD moose and from North American CWD. The isolate showed nevertheless features similar to the classical BSE (BSE-C) strain. Furthermore, BSE-C could not be excluded based on the PrPSc immunohistochemistry staining in the brainstem and the absence of detectable PrPSc in the lymphoid tissues. Because of the known ability of BSE-C to cross species barriers as well as its zoonotic potential, the CWD red deer isolate was submitted to the EURL Strain Typing Expert Group (STEG) as a BSE-C suspect for further investigation. In addition, different strain typing in vivo and in vitro strategies aiming at identifying the BSE-C strain in the red deer isolate were performed independently in three research groups and BSE-C was not found in it. These results suggest that the Norwegian CWD red deer case was infected with a previously unknown CWD type and further investigation is needed to determine the characteristics of this potential new CWD strain.


Assuntos
Cervos , Encefalopatia Espongiforme Bovina , Doença de Emaciação Crônica , Animais , Noruega , Western Blotting/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Príons/metabolismo , Bovinos , Imuno-Histoquímica/veterinária , Proteínas PrPSc/metabolismo
2.
Open Forum Infect Dis ; 11(2): ofae073, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38390463

RESUMO

Background: Longitudinal data on the detectability of monkeypox virus (MPXV) genetic material in different specimen types are scarce. Methods: We describe MPXV-specific polymerase chain reaction (PCR) results from adults with confirmed mpox infection from Toronto, Canada, including a cohort undergoing weekly collection of specimens from multiple anatomic sites until 1 week after skin lesions had fully healed. We quantified the time from symptom onset to resolution of detectable viral DNA (computed tomography [Ct] ≥ 35) by modeling exponential decay in Ct value as a function of illness day for each site, censoring at the time of tecovirimat initiation. Results: Among 64 men who have sex with men, the median (interquartile range [IQR]) age was 39 (32.75-45.25) years, and 49% had HIV. Twenty received tecovirimat. Viral DNA was detectable (Ct < 35) at baseline in 74% of genital/buttock/perianal skin swabs, 56% of other skin swabs, 44% of rectal swabs, 37% of throat swabs, 27% of urine, 26% of nasopharyngeal swabs, and 8% of semen samples. The median time to resolution of detectable DNA (IQR) was longest for genital/buttock/perianal skin and other skin swabs at 30.0 (23.0-47.9) and 22.4 (16.6-29.4) days, respectively, and shortest for nasopharyngeal swabs and semen at 0 (0-12.1) and 0 (0-0) days, respectively. We did not observe an effect of tecovirimat on the rate of decay in viral DNA detectability in any specimen type (all P > .05). Conclusions: MPXV DNA detectability varies by specimen type and persists for over 3-4 weeks in skin specimens. The rate of decay did not differ by tecovirimat use in this nonrandomized study.

3.
Can Med Educ J ; 14(5): 110-112, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-38045086

RESUMO

We developed a pharmacist-led one-month teaching rotation for medical residents to learn HIV pharmacotherapy. The postgraduate-year-3 residents found this interprofessional learning experience extremely valuable to their future practice in HIV care. The overarching concept of this rotation was for the medical trainee to "become-the-pharmacist," learning to recognize, prevent, and manage drug-related issues in HIV patients. To support medical training in other highly specialized pharmacotherapeutic areas we suggest considering a pharmacist-led interprofessional learning experience.


Nous avons développé un stage d'enseignement sur la pharmacothérapie du VIH guidé par un pharmacien pour les résidents en médecine de troisième année. Ces derniers ont trouvé cette expérience d'apprentissage interprofessionnel extrêmement enrichissante pour leur pratique future en lien avec le traitement du VIH. Le concept au cœur de ce stage d'une durée d'un mois était de mettre les apprenants dans la peau du pharmacien pour qu'ils apprennent à reconnaître, à prévenir et à prendre en charge les problèmes liés à la prise de médicaments chez les patients séropositifs. Nous recommandons des opportunités d'apprentissage interprofessionnel mené par un pharmacien pour appuyer la formation médicale dans d'autres domaines hautement spécialisés de la pharmacothérapie.


Assuntos
Infecções por HIV , Internato e Residência , Humanos , Medicina de Família e Comunidade/educação , Farmacêuticos , Currículo , Infecções por HIV/tratamento farmacológico
4.
Methods Mol Biol ; 2702: 467-487, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37679636

RESUMO

Peptide phage display has historically been used to epitope map monoclonal antibodies. More recently, by coupling this method with next-generation sequencing (so-called next-generation phage display, NGPD) to mass screen peptide binding events, the methodology has been successfully applied to map polyclonal antibody responses to infection. This leads to the identification of panels of mimotopes that represent the pathogen's epitopes. One potential advantage of using such an approach is that the mimotopes can represent not just linear epitopes but also conformational epitopes or those produced from post-translational modifications of proteins or from other non-protein macromolecules. The mapping of such complex immunological recognition of a pathogen can inform novel serological assay development and vaccine design. Here, we provide detailed methods for the application of NGPD to identify panels of mimotopes that are recognized specifically by antibodies from individuals with a particular infection.


Assuntos
Formação de Anticorpos , Bacteriófagos , Humanos , Anticorpos Monoclonais , Técnicas de Visualização da Superfície Celular , Epitopos , Bacteriófagos/genética
5.
Sci Rep ; 13(1): 3452, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859422

RESUMO

Prion diseases are progressive neurodegenerative disorders with no effective therapeutics. The central event leading to the pathology in the diseases is the conversion of PrPC into PrPSc and its accumulation in the central nervous system. Previous studies demonstrated that recombinant PrP (rPrP) and PrP peptides can inhibit the formation of PrPSc. Here, the effectiveness of ovine rPrP mutants at codon 136 and peptides derived from this region were assessed for their ability to inhibit PrPSc replication, using protein misfolding cyclic amplification (PMCA). Based on a rPrP VRQ (rVRQ) genotype background (positions 136, 154 and 171) and mutations at position 136, the most effective inhibitors were V136R, V136K and V136P mutants, with IC50 values of 1 to 2 nM; activities much more potent than rVRQ (114 nM). rRRQ and rKRQ were also shown to effectively inhibit multiple ruminant prion amplification reactions that used distinct prion strain seeds and substrate PRNP genotypes. rRRQ, rKRQ and rPRQ were also shown to effectively protect Rov9 cells from scrapie infection when applied at 250 nM. The study demonstrates for the first time that the rPrP sequence can be mutated at sites known to be involved in prion disease susceptibility, to produce inhibitors with improved efficacy.


Assuntos
Príons , Scrapie , Ovinos , Animais , Proteínas Priônicas , Carneiro Doméstico , Potenciais de Ação
6.
Antibodies (Basel) ; 12(1)2023 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-36648891

RESUMO

Driven by necessity, the COVID-19 pandemic caused by SARS-CoV-2 has accelerated the development and implementation of new vaccine platforms and other viral therapeutics. Among these is the therapeutic use of antibodies including single-domain antibodies, in particular the camelid variable heavy-chain fragment (VHH). Such therapies can provide a critical interim intervention when vaccines have not yet been developed for an emerging virus. It is evident that an increasing number of different viruses are emerging and causing epidemics and pandemics with increasing frequency. It is therefore imperative that we capitalize on the experience and knowledge gained from combatting COVID-19 to be better prepared for the next pandemic.

7.
Methods Mol Biol ; 2591: 189-218, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36350550

RESUMO

Phage display (PD) is a powerful method and has been extensively used to generate monoclonal antibodies and identify epitopes, mimotopes, and protein interactions. More recently, the combination of next-generation sequencing (NGS) with PD (NGPD) has revolutionized the capabilities of the method by creating large data sets of sequences from affinity selection-based approaches (biopanning) otherwise challenging to obtain. NGPD can monitor motif enrichment, allow tracking of the selection process over consecutive rounds, and highlight unspecific binders. To tackle the wealth of data obtained, bioinformatics tools have been developed that allow for identifying specific binding sequences (binders) that can then be validated. Here, we provide a detailed account of the use of NGPD experiments to identify ubiquitin-specific protease peptide ligands.


Assuntos
Bacteriófagos , Biblioteca de Peptídeos , Ligantes , Peptídeos , Enzimas Desubiquitinantes
8.
Artigo em Inglês | MEDLINE | ID: mdl-36483375

RESUMO

Objective: To describe the evolution of respiratory antibiotic prescribing during the coronavirus disease 2019 (COVID-19) pandemic across 3 large hospitals that maintained antimicrobial stewardship services throughout the pandemic. Design: Retrospective interrupted time-series analysis. Setting: A multicenter study was conducted including medical and intensive care units (ICUs) from 3 hospitals within a Canadian epicenter for COVID-19. Methods: Interrupted time-series analysis was used to analyze rates of respiratory antibiotic utilization measured in days of therapy per 1,000 patient days (DOT/1,000 PD) in medical units and ICUs. Each of the first 3 waves of the pandemic were compared to the baseline. Results: Within the medical units, use of respiratory antibiotics increased during the first wave of the pandemic (rate ratio [RR], 1.76; 95% CI, 1.38-2.25) but returned to the baseline in waves 2 and 3 despite more COVID-19 admissions. In ICU, the use of respiratory antibiotics increased in wave 1 (RR, 1.30; 95% CI, 1.16-1.46) and wave 2 of the pandemic (RR, 1.21; 95% CI, 1.11-1.33) and returned to the baseline in the third wave, which had the most COVID-19 admissions. Conclusions: After an initial surge in respiratory antibiotic prescribing, we observed the normalization of prescribing trends at 3 large hospitals throughout the COVID-19 pandemic. This trend may have been due to the timely generation of new research and guidelines developed with frontline clinicians, allowing for the active application of new research to clinical practice.

9.
Patient Prefer Adherence ; 16: 2461-2472, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36090124

RESUMO

Purpose: Use of patient-reported outcomes assessments (PROs) can improve patient-provider communication and focus provider attention on current health issues. This analysis examines the association between suboptimal antiretroviral therapy (ART) adherence and factors obtained through PROs among people with HIV (PWH) at 2 North American outpatient clinics. Patients and Methods: Immediately before a clinic visit, PWH completed self-administered PROs. Unadjusted and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated from logistic regression models to identify sociodemographic and health-related factors (satisfaction with ART, difficulty meeting housing costs, depression, intimate partner violence, risk of malnutrition, smoking status, alcohol use, and substance use) associated with suboptimal adherence (defined as self-reporting <95% or <80% adherence). Multiple imputation was performed to account for missing data in the multivariate analyses. Results: Of 1632 PWH, 1239 (76%) responded to the adherence assessment; of these, 268 (22%) and 106 (9%) reported <95% and <80% adherence, respectively. Of 1580 PWH who responded, 354 (22%) were dissatisfied with their HIV medication. Of responding PWH, 19% reported moderate-to-severe depression, 23% indicated they were at risk of malnutrition, 34% were current smokers, and 62% reported substance use in the past 3 months. Dissatisfaction with ART was significantly associated with <95% and <80% adherence in the unadjusted analysis (unadjusted OR [95% CI], 3.38 [2.51-4.56] and 4.26 [2.82-6.42], respectively) and adjusted analysis (adjusted OR [95% CI], 2.76 [1.91-4.00] and 3.28 [1.95-5.52], respectively); significance remained after multiple imputation. In adjusted analyses, no risk of malnutrition was significantly associated with reduced odds of <95% adherence after multiple imputation (adjusted OR [95% CI], 0.714 [0.511-0.997]); no other factors were associated with <95% or <80% adherence. Conclusion: These results suggest that implementation of PROs evaluating treatment satisfaction may provide value to adherence management in routine HIV care.

10.
Mol Biotechnol ; 64(7): 791-803, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35107752

RESUMO

Phage display technology utilises peptide and antibody libraries with very high diversities to select ligands with specific binding properties. The production of such libraries can be labour intensive and technically challenging and whilst there are commercial sources of libraries, the exploitation of the resulting binders is constrained by ownership of the libraries. Here, a peptide library of ~ 1 × 109 variants for display on gene VIII was produced alongside three VHH antibody libraries with similar diversity, where 12mer, 16mer or 21mer CDR3s were introduced into the highly stable cAbBCII10 scaffold displayed on gene III. The cloning strategy used a simple whole-plasmid PCR method and type IIS restriction enzyme assembly that facilitate the seamless insertion of diversity into any suitable phage coat protein or antibody scaffold. This method reproducibly produced 1 × 109 variants from just 10 transformations and the four libraries had relatively low bias with 82 to 86% of all sequences present as single copies. The functionality of both peptide and antibody libraries were demonstrated by selection of ligands with specific binding properties by biopanning. The peptide library was used to epitope map a monoclonal antibody. The VHH libraries were pooled and used to select an antibody to recombinant human collagen type 1.


Assuntos
Bacteriófagos , Biblioteca de Peptídeos , Bacteriófagos/genética , Humanos , Ligantes , Peptídeos/genética , Plasmídeos/genética , Reação em Cadeia da Polimerase
11.
AIDS Behav ; 26(7): 2409-2424, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35064851

RESUMO

The PROgress study assessed the value and feasibility of implementing web-based patient-reported outcomes assessments (PROs) within routine HIV care at two North American outpatient clinics. People with HIV (PWH) completed PROs on a tablet computer in clinic before their routine care visit. Data collection included PROs from 1632 unique PWH, 596 chart reviews, 200 patient questionnaires, and 16 provider/staff questionnaires. During an initial setup phase involving 200 patients, PRO results were not delivered to providers; for all subsequent patients, providers received PRO results before the consultation. Chart review demonstrated that delivery of PRO results to providers improved patient-provider communication and increased the number of complex health and behavioral issues identified, recorded, and acted on, including suicidal ideation (88% with vs 38% without PRO feedback) and anxiety (54% with vs 24% without PRO feedback). In post-visit questionnaires, PWH (82%) and providers (82%) indicated that the PRO added value to the visit.


Assuntos
Infecções por HIV , Eletrônica , Infecções por HIV/tratamento farmacológico , Humanos , América do Norte , Medidas de Resultados Relatados pelo Paciente , Inquéritos e Questionários
12.
Clin Infect Dis ; 74(5): 846-853, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-34175944

RESUMO

BACKGROUND: We implemented an opt-out clinic-based intervention pairing syphilis tests with routine human immunodeficiency virus (HIV) viral load testing. The primary objective was to determine the degree to which this intervention increased the detection of early syphilis. METHODS: The Enhanced Syphilis Screening Among HIV-Positive Men (ESSAHM) Trial was a stepped wedge cluster-randomized controlled trial involving 4 urban HIV clinics in Ontario, Canada, from 2015 to 2017. The population was HIV-positive adult males. The intervention was standing orders for syphilis serological testing with viral loads, and control was usual practice. We obtained test results via linkage with the centralized provincial laboratory and defined cases using a standardized clinical worksheet and medical record review. We employed a generalized linear mixed model with a logit link to estimate odds ratios (ORs) and 95% confidence intervals (CIs) of the intervention. RESULTS: A total of 3895 men were followed over 7471 person-years. The mean number of syphilis tests increased from 0.53 to 2.02 tests per person per year. There were 217 new diagnoses of syphilis (control, 81; intervention, 136), for which 147 (68%) were cases of early syphilis (control, 61 [75%]; intervention, 86 [63%]). The annualized proportion with newly detected early syphilis increased from 0.009 to 0.032 with implementation of the intervention; the corresponding time-adjusted OR was 1.25 (95% CI, .71-2.20). CONCLUSIONS: The implementation of standing orders for syphilis testing with HIV viral loads was feasible and increased testing, yet produced less-than-expected increases in case detection compared to past uncontrolled pre-post trials. CLINICAL TRIALS REGISTRATION: NCT02019043.


Assuntos
Infecções por HIV , Sífilis , Adulto , HIV , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Programas de Rastreamento , Ontário/epidemiologia , Sífilis/diagnóstico , Sífilis/epidemiologia
13.
Int J STD AIDS ; 33(3): 247-256, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34293990

RESUMO

BACKGROUND: An optimal adherence to antiretroviral therapy (ART) is fundamental for suppression of HIV viral load and favourable treatment outcomes. Patient-reported outcomes (PROs) are effective tools for improving patient-provider communication and focusing providers' awareness on current health problems. The objectives of this analysis were (1) to determine the feasibility of implementing an electronic screening tool to measure PROs in a Canadian HIV clinic to obtain information on ART adherence and related factors and (2) to determine the factors related to sub-optimal adherence. METHODS: This implementation research with a convenience sample of 600 people living with HIV (PLWH) was conducted in a busy, academic, urban HIV clinic in Toronto, Canada. PLWH were approached to participate in PRO assessments just prior to their in-clinic appointments, including health-related domains such as mental health, housing, nutrition, financial stress and medication adherence, and responses were summarized on a single sheet available for providers to review. Feasibility of implementing PROs was assessed by quantifying response rate, completion rate, time taken and participation rate. Medication adherence was elicited by self-report of the percentage of prescribed HIV medications taken in the last month. Unadjusted and adjusted odds ratios were estimated from logistic regression models to identify factors associated with adherence of <95%. RESULTS: Of the 748 PLWH invited to participate, 692 (participation rate: 92.5%) completed the PRO assessments as standard of care in clinic. Of these, 600 consented to the use of their PRO results for research and were included in this analysis. The average response rate to the ART-related questions was 96.8% and mean completion rate was 95.5%. The median time taken to complete the assessment was 12.0 (IQR = 8.4-17.3) min, adjusted 8.7 (IQR = 7.2-10.8) min. 445 (74.9%) of participants were male, and 153 (26.2%) reported dissatisfaction with ART. 105 (19.7%) of the PLWH reported ART adherence of <95%. Multivariable logistic regression identified the following risk factors for sub-optimal adherence: dissatisfaction with ART (OR = 2.30, 95% CI 1.38-3.83), not having a family doctor or not visiting a family doctor in last year (OR = 1.69, 95% CI 1.02-2.79). CONCLUSION: Collecting self-reported health information from PLWH through PROs in a busy urban clinic was feasible and can provide relevant information to healthcare providers on issues related to adherence. This has a potential to help in individualizing ambulatory care.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Fármacos Anti-HIV/uso terapêutico , Canadá/epidemiologia , Eletrônica , Estudos de Viabilidade , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , Humanos , Masculino , Adesão à Medicação , Medidas de Resultados Relatados pelo Paciente
16.
Sci Rep ; 11(1): 11931, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099797

RESUMO

To understand the possible role of mixed-prion infections in disease presentation, the current study reports the co-infection of sheep with bovine spongiform encephalopathy (BSE) and scrapie. The bovine BSE agent was inoculated subcutaneously into sheep with ARQ/ARQ or VRQ/ARQ PRNP genotypes either at the same time as subcutaneous challenge with scrapie, or three months later. In addition, VRQ/VRQ sheep naturally infected with scrapie after being born into a scrapie-affected flock were challenged subcutaneously with BSE at eight or twenty one months-of-age. Sheep were analysed by incubation period/attack rate, and western blot of brain tissue determined the presence of BSE or scrapie-like PrPSc. Serial protein misfolding cyclic amplification (sPMCA) that can detect very low levels of BSE in the presence of an excess of scrapie agent was also applied to brain and lymphoreticular tissue. For VRQ/ARQ sheep challenged with mixed infections, scrapie-like incubation periods were produced, and no BSE agent was detected. However, whilst ARQ/ARQ sheep developed disease with BSE-like incubation periods, some animals had a dominant scrapie western blot phenotype in brain, but BSE was detected in these sheep by sPMCA. In addition, VRQ/VRQ animals challenged with BSE after natural exposure to scrapie had scrapie-like incubation periods and dominant scrapie PrPSc in brain, but one sheep had BSE detectable by sPMCA in the brain. Overall, the study demonstrates for the first time that for scrapie/BSE mixed infections, VRQ/ARQ sheep with experimental scrapie did not propagate BSE but VRQ/VRQ sheep with natural scrapie could propagate low levels of BSE, and whilst BSE readily propagated in ARQ/ARQ sheep it was not always the dominant PrPSc strain in brain tissue. Indeed, for several animals, a dominant scrapie biochemical phenotype in brain did not preclude the presence of BSE prion.


Assuntos
Doenças dos Bovinos/diagnóstico , Coinfecção/diagnóstico , Encefalopatia Espongiforme Bovina/diagnóstico , Scrapie/diagnóstico , Doenças dos Ovinos/diagnóstico , Animais , Encéfalo/metabolismo , Bovinos , Doenças dos Bovinos/metabolismo , Coinfecção/genética , Coinfecção/metabolismo , Encefalopatia Espongiforme Bovina/complicações , Encefalopatia Espongiforme Bovina/metabolismo , Genótipo , Fenótipo , Proteínas Priônicas/genética , Proteínas Priônicas/metabolismo , Scrapie/complicações , Scrapie/metabolismo , Ovinos , Doenças dos Ovinos/genética , Doenças dos Ovinos/metabolismo
17.
CMAJ ; 192(43): E1334-E1335, 2020 10 26.
Artigo em Francês | MEDLINE | ID: mdl-33106309
20.
Mol Biotechnol ; 61(11): 801-815, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31468301

RESUMO

Phage display antibody libraries have proven an invaluable resource for the isolation of diagnostic and potentially therapeutic antibodies, the latter usually being antibody fragments converted into IgG formats. Recent advances in the production of highly diverse and functional antibody libraries are considered here, including for Fabs, scFvs and nanobodies. These advances include codon optimisation during generation of CDR diversity, improved display levels using novel signal sequences, molecular chaperones and isomerases and the use of highly stable scaffolds with relatively high expression levels. In addition, novel strategies for the batch reformatting of scFv and Fab phagemid libraries, derived from phage panning, into IgG formats are described. These strategies allow the screening of antibodies in the end-use format, facilitating more efficient selection of potential therapeutics.


Assuntos
Técnicas de Visualização da Superfície Celular , Fragmentos Fab das Imunoglobulinas/genética , Anticorpos de Cadeia Única/genética , Animais , Afinidade de Anticorpos , Bacteriófagos , Camelidae/imunologia , Regiões Determinantes de Complementaridade/genética , Vetores Genéticos , Humanos , Imunoglobulina G/imunologia , Biblioteca de Peptídeos , Tubarões/imunologia
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