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1.
Virology ; 600: 110269, 2024 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-39437533

RESUMEN

Infectious bursal disease virus (IBDV) causes a major immunosuppressive disease of chickens. As part of ongoing epidemiological surveillance for IBDV, the hypervariable region (HVR) of the VP2 capsid gene encoded by segment A, and a region of the VP1 polymerase gene, encoded by segment B, were sequenced from 20 IBDV-positive bursal samples obtained in 2020 and 2021, from 16 commercial British broiler farms. Birds had received a live IBDV vaccine at 17-22 days of age, and samples were obtained at 25-55 days of age. Of the 16 farms, none contained very virulent (vv) strains, one contained a classical virulent strain, two contained vaccine strains, and five contained sequences of reassortant strains with a vv segment A and a non-vv segment B belonging to genogroup A3B1. In eight of the farms, we identified the sequences of both genogroup A3B1 reassortant strains and vaccine strains in the same samples. Therefore, the majority of the farms (13/16 (81%)) contained genogroup A3B1 reassortant viruses. Of the flocks containing reassortant strains, 5/13 (38%) had HVR mutations Q219L, G254D, D279N, and N280T, consistent with a recently described Western European clade, but the rest had other mutations or no mutations, demonstrating that multiple clades were present in the samples. Taken together, vv strains were not detected, but reassortant strains predominated in the farms, which belonged to different clades, and were frequently found together with vaccine strains.

2.
J Virol ; 98(9): e0124024, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39087765

RESUMEN

Science is humanity's best insurance against threats from nature, but it is a fragile enterprise that must be nourished and protected. The preponderance of scientific evidence indicates a natural origin for SARS-CoV-2. Yet, the theory that SARS-CoV-2 was engineered in and escaped from a lab dominates media attention, even in the absence of strong evidence. We discuss how the resulting anti-science movement puts the research community, scientific research, and pandemic preparedness at risk.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/virología , COVID-19/transmisión , Pandemias , Animales
3.
BMC Palliat Care ; 23(1): 172, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39010021

RESUMEN

BACKGROUND: Patients receiving palliative care are often on complex medication regimes to manage their symptoms and comorbidities and at high risk of medication-related problems. The aim of this cross-sectional study was to evaluate the involvement of a pharmacist to an existing community specialist palliative care telehealth service on patients' medication management. METHOD: The specialist palliative care pharmacist attended two palliative care telehealth sessions per week over a six-month period (October 2020 to March 2021). Attendance was allocated based on funding received. Data collected from the medication management reviews included prevalence of polypharmacy, number of inappropriate medication according to the Screening Tool of Older Persons Prescriptions in Frail adults with limited life expectancy criteria (STOPP/FRAIL) and recommendations on deprescribing, symptom control and medication management. RESULTS: In total 95 patients participated in the pharmaceutical telehealth service with a mean age of 75.2 years (SD 10.67). Whilst 81 (85.3%) patients had a cancer diagnosis, 14 (14.7%) had a non-cancer diagnosis. At referral, 84 (88.4%, SD 4.57) patients were taking ≥ 5 medications with 51 (53.7%, SD 5.03) taking ≥ 10 medications. According to STOPP/FRAIL criteria, 142 potentially inappropriate medications were taken by 54 (56.8%) patients, with a mean of 2.6 (SD 1.16) inappropriate medications per person. Overall, 142 recommendations were accepted from the pharmaceutical medication management review including 49 (34.5%) related to deprescribing, 20 (14.0%) to medication-related problems, 35 (24.7%) to symptom management and 38 (26.8%) to medication administration. CONCLUSION: This study provided evidence regarding the value of including a pharmacist in palliative care telehealth services. Input from the pharmacist resulted in improved symptom management of community palliative care patients and their overall medication management.


Asunto(s)
Cuidados Paliativos , Farmacéuticos , Telemedicina , Humanos , Estudios Transversales , Cuidados Paliativos/métodos , Cuidados Paliativos/normas , Anciano , Telemedicina/normas , Femenino , Masculino , Anciano de 80 o más Años , Administración del Tratamiento Farmacológico/normas , Polifarmacia , Persona de Mediana Edad
4.
Age Ageing ; 53(4)2024 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-38594928

RESUMEN

BACKGROUND: Emergency department (ED) clinicians are more frequently providing care, including end-of-life care, to older people. OBJECTIVES: To estimate the need for ED end-of-life care for people aged ≥65 years, describe characteristics of those dying within 48 hours of ED presentation and compare those dying in ED with those dying elsewhere. METHODS: We conducted a retrospective cohort study analysing data from 177 hospitals in Australia and New Zealand. Data on older people presenting to ED from January to December 2018, and those who died within 48 hours of ED presentation, were analysed using simple descriptive statistics and univariate logistic regression. RESULTS: From participating hospitals in Australia or New Zealand, 10,921 deaths in older people occurred. The 48-hour mortality rate was 6.43 per 1,000 ED presentations (95% confidence interval: 6.31-6.56). Just over a quarter (n = 3,067, 28.1%) died in ED. About one-quarter of the cohort (n = 2,887, 26.4%) was triaged into less urgent triage categories. Factors with an increased risk of dying in ED included age 65-74 years, ambulance arrival, most urgent triage categories, principal diagnosis of circulatory system disorder, and not identifying as an Aboriginal or Torres Strait Islander person. Of the 7,677 older people admitted, half (n = 3,836, 50.0%) had an encounter for palliative care prior to, or during, this presentation. CONCLUSIONS: Our findings provide insight into the challenges of recognising the dying older patient and differentiating those appropriate for end-of-life care. We support recommendations for national advanced care planning registers and suggest a review of triage systems with an older person-focused lens.


Asunto(s)
Servicio de Urgencia en Hospital , Hospitalización , Anciano , Humanos , Australia/epidemiología , Nueva Zelanda/epidemiología , Estudios Retrospectivos
5.
Aust Health Rev ; 48: 201-206, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38467110

RESUMEN

There is an urgent and unmet need for specialist palliative care services in residential aged care. The Specialist Palliative Care in Aged Care (SPACE) Project aimed to improve palliative and end-of-life care for older people living in residential aged care facilities in Queensland. A representative working group developed a series of service principles around palliative care practice in aged care (comprehensive resident-focused care, streamlined service, and capacity building). Funding was allocated by population to the health services in Queensland to adapt and implement models of care aligned with these principles. SPACE successfully implemented a variety of decentralised models of care across Queensland. The critical elements for the success of SPACE were the use of an expert working group to define the core innovation, networking and implementation support from the central project team and community of practice, and adaptable models of care led by local facilitators. Lessons learned from this real-world case study could be adopted to guide and ensure the successful implementation and sustainability of future complex interventions in healthcare settings, both nationally and internationally.


Asunto(s)
Cuidados Paliativos , Cuidado Terminal , Humanos , Anciano , Queensland , Atención a la Salud
7.
J Virol ; 98(1): e0179123, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38168672

RESUMEN

In the United States (US), biosafety and biosecurity oversight of research on viruses is being reappraised. Safety in virology research is paramount and oversight frameworks should be reviewed periodically. Changes should be made with care, however, to avoid impeding science that is essential for rapidly reducing and responding to pandemic threats as well as addressing more common challenges caused by infectious diseases. Decades of research uniquely positioned the US to be able to respond to the COVID-19 crisis with astounding speed, delivering life-saving vaccines within a year of identifying the virus. We should embolden and empower this strength, which is a vital part of protecting the health, economy, and security of US citizens. Herein, we offer our perspectives on priorities for revised rules governing virology research in the US.


Asunto(s)
Investigación Biomédica , Contención de Riesgos Biológicos , Virología , Humanos , COVID-19 , Estados Unidos , Virus , Investigación Biomédica/normas
8.
Emerg Med Australas ; 36(1): 13-23, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37914673

RESUMEN

OBJECTIVES: To describe the characteristics of, and care provided to, older people who died within 48 h of ED presentation. METHODS: A descriptive retrospective cohort study of people 65 years and older presenting to two EDs in Queensland, Australia, between April 2018 and March 2019. Data from electronic medical records were collected and analysed. RESULTS: Two hundred and ninety-five older people who died within 48 h of ED presentation were included. Nearly all arrived by ambulance (92%, n = 272) and 36% (n = 106) were from aged care facilities. Three-quarters (75%, n = 222) were triaged into the most urgent triage categories (i.e. Australasian Triage Scale; ATS 1/2). Fewer than half were previously independent with mobility (38%, n = 111) and activities of daily living (43%, n = 128). Sixty-one per cent (n = 181) had a pre-existing healthcare directive. Twenty-two per cent (n = 66) died in ED, most commonly due to pneumonia, intracerebral haemorrhage, cardiac arrest and/or sepsis. Over half had one or more ED visits (52%, n = 154) and/or hospital admissions (52%, n = 152) 6 months prior. CONCLUSIONS: Identification of patients at end-of-life (EoL) is not always straightforward; consider recent reduction in independence and recent ED visits/hospital admissions. System-based strategies that span pre-hospital, ED and in-patient care are recommended to facilitate EoL pathway implementation and care continuity.


Asunto(s)
Actividades Cotidianas , Cuidado Terminal , Humanos , Anciano , Estudios Retrospectivos , Servicio de Urgencia en Hospital , Muerte
9.
J Med Microbiol ; 72(10)2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37801020

RESUMEN

Avian reoviruses (ARVs) have a significant economic impact on the poultry industry, affecting commercial and backyard flocks. Spread feco-orally, or vertically, many do not cause morbidity, but pathogenic strains can contribute to several diseases, including tenosynovitis/arthritis, which is clinically the most significant. The last decade has seen a surge in cases in the US, and due to ongoing evolution, seven genotypic clusters have now been identified. Control efforts include strict biosecurity and vaccination with commercial and autogenous vaccines. Research priorities include improving understanding of pathogenesis and developing new vaccines guided by ongoing molecular and serologic surveillance.


Asunto(s)
Orthoreovirus Aviar , Enfermedades de las Aves de Corral , Infecciones por Reoviridae , Animales , Orthoreovirus Aviar/genética , Pollos , Enfermedades de las Aves de Corral/prevención & control , Infecciones por Reoviridae/veterinaria , Infecciones por Reoviridae/epidemiología , Filogenia
10.
Front Immunol ; 14: 1197746, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37744374

RESUMEN

Introduction: Infectious Bursal Disease Virus (IBDV) causes immunosuppression in chickens. While B-cell destruction is the main cause of humoral immunosuppression, bursal T cells from IBDV-infected birds have been reported to inhibit the mitogenic response of splenocytes, indicating that some T cell subsets in the infected bursa have immunomodulatory activities. CD4+CD25+TGFß+ cells have been recently described in chickens that have immunoregulatory properties and play a role in the pathogenesis of Marek's Disease Virus. Methods: To evaluate if CD4+CD25+TGFß+ cells infiltrated the bursa of Fabricius (BF) following IBDV infection, and influenced the outcome of infection, birds were inoculated at either 2 days or 2 weeks of age with vaccine strain (228E), classic field strain (F52/70), or PBS (mock), and bursal cell populations were quantified by flow cytometry. Results: Both 228E and F52/70 led to atrophy of the BF, a significant reduction of Bu1+-B cells, and a significant increase in CD4+ and CD8α+ T cells in the BF, but only F52/70 caused suppression of immune responses to a test antigen in younger birds, and clinical signs in older birds. Virus was cleared from the BF more rapidly in younger birds than older birds. An infiltration of CD4+CD25+T cells into the BF, and elevated expression of bursal TGFß-1+ mRNA was observed at all time points following infection, irrespective of the strain or age of the birds, but CD4+TGFß+cells and CD4+CD25+TGFß+ cells only appeared in the BF at 28 dpi in younger birds. In older birds, CD4+TGFß+ cells and CD4+CD25+TGFß+ cells were present at earlier time points, from 7dpi following 228E infection, and from 14 and 28 dpi following F52/70 infection, respectively. Discussion: Our data suggest that an earlier infiltration of CD4+TGFß+ cells into the BF correlated with a delayed clearance of virus. However, the influx of CD4+TGFß+ cells and CD4+CD25+TGFß+ into the BF did not correlate with increased pathogenicity, or immunosuppression.


Asunto(s)
Virus de la Enfermedad Infecciosa de la Bolsa , Animales , Bolsa de Fabricio , Pollos , Terapia de Inmunosupresión , Factor de Crecimiento Transformador beta
11.
J Gen Virol ; 104(8)2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37589541

RESUMEN

Viruses emerging from wildlife can cause outbreaks in humans and domesticated animals. Predicting the emergence of future pathogens and mitigating their impacts requires an understanding of what shapes virus diversity and dynamics in wildlife reservoirs. In order to better understand coronavirus ecology in wild species, we sampled birds within a coastal freshwater lagoon habitat across 5 years, focussing on a large population of mute swans (Cygnus olor) and the diverse species that they interact with. We discovered and characterised the full genome of a divergent gammacoronavirus belonging to the Goose coronavirus CB17 species. We investigated the genetic diversity and dynamics of this gammacoronavirus using untargeted metagenomic sequencing of 223 faecal samples from swans of known age and sex, and RT-PCR screening of 1632 additional bird samples. The virus circulated persistently within the bird community; virus prevalence in mute swans exhibited seasonal variations, but did not change with swan age-class or epidemiological year. One whole genome was fully characterised, and revealed that the virus originated from a recombination event involving an undescribed gammacoronavirus species. Multiple lineages of this gammacoronavirus co-circulated within our study population. Viruses from this species have recently been detected in aquatic birds from both the Anatidae and Rallidae families, implying that host species habitat sharing may be important in shaping virus host range. As the host range of the Goose coronavirus CB17 species is not limited to geese, we propose that this species name should be updated to 'Waterbird gammacoronavirus 1'. Non-invasive sampling of bird coronaviruses may provide a tractable model system for understanding the evolutionary and cross-species dynamics of coronaviruses.


Asunto(s)
Anseriformes , Infecciones por Coronavirus , Coronavirus , Gammacoronavirus , Humanos , Animales , Gammacoronavirus/genética , Coronavirus/genética , Brotes de Enfermedades , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/veterinaria , Animales Salvajes , Variación Genética , Recombinación Genética
12.
Int J Mol Sci ; 24(10)2023 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-37239817

RESUMEN

The use of infectious bursal disease virus (IBDV) reverse genetics to engineer tagged reporter viruses has revealed that the virus factories (VFs) of the Birnaviridae family are biomolecular condensates that show properties consistent with liquid-liquid phase separation (LLPS). Although the VFs are not bound by membranes, it is currently thought that viral protein 3 (VP3) initially nucleates the formation of the VF on the cytoplasmic leaflet of early endosomal membranes, and likely drives LLPS. In addition to VP3, IBDV VFs contain VP1 (the viral polymerase) and the dsRNA genome, and they are the sites of de novo viral RNA synthesis. Cellular proteins are also recruited to the VFs, which are likely to provide an optimal environment for viral replication; the VFs grow due to the synthesis of the viral components, the recruitment of other proteins, and the coalescence of multiple VFs in the cytoplasm. Here, we review what is currently known about the formation, properties, composition, and processes of these structures. Many open questions remain regarding the biophysical nature of the VFs, as well as the roles they play in replication, translation, virion assembly, viral genome partitioning, and in modulating cellular processes.


Asunto(s)
Birnaviridae , Virus de la Enfermedad Infecciosa de la Bolsa , Birnaviridae/metabolismo , Compartimentos de Replicación Viral , Línea Celular , Replicación Viral , Proteínas Virales/genética , Proteínas Virales/metabolismo , Vesículas Transportadoras/metabolismo , Proteínas Estructurales Virales/metabolismo
13.
Curr Protoc ; 3(1): e639, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36622206

RESUMEN

Infectious bursal disease virus (IBDV) is a major threat to the productivity of the poultry industry due to morbidity, mortality, and immunosuppression that exacerbates secondary infections and reduces the efficacy of vaccination programs. Field strains of IBDV have a preferred tropism for chicken B cells, the majority of which reside in the bursa of Fabricius (BF). IBDV adaptation to adherent cell culture is associated with mutations altering amino acids in the hypervariable region (HVR) of the capsid protein, which affects immunogenicity and virulence. Until recently, this has limited both the application of reverse genetics systems for engineering molecular clones, and the use of in vitro neutralization assays, to cell-culture-adapted strains of IBDV. Here, we describe the rescue of molecular clones of IBDV containing the HVR from diverse field strains, along with a neutralization assay to quantify antibody responses against the rescued viruses, both using chicken B cells. These methods are readily adaptable to any laboratory with molecular biology expertise and negate the need to obtain wild-type strains. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol 1: A chicken B-cell rescue system for IBDV Basic Protocol 2: A chicken B-cell neutralization assay for IBDV.


Asunto(s)
Infecciones por Birnaviridae , Virus de la Enfermedad Infecciosa de la Bolsa , Animales , Pollos/genética , Virus de la Enfermedad Infecciosa de la Bolsa/genética , Genética Inversa , Infecciones por Birnaviridae/veterinaria , Bolsa de Fabricio
14.
J Virol ; 97(2): e0008923, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36700640

RESUMEN

Viruses have brought humanity many challenges: respiratory infection, cancer, neurological impairment and immunosuppression to name a few. Virology research over the last 60+ years has responded to reduce this disease burden with vaccines and antivirals. Despite this long history, the COVID-19 pandemic has brought unprecedented attention to the field of virology. Some of this attention is focused on concern about the safe conduct of research with human pathogens. A small but vocal group of individuals has seized upon these concerns - conflating legitimate questions about safely conducting virus-related research with uncertainties over the origins of SARS-CoV-2. The result has fueled public confusion and, in many instances, ill-informed condemnation of virology. With this article, we seek to promote a return to rational discourse. We explain the use of gain-of-function approaches in science, discuss the possible origins of SARS-CoV-2 and outline current regulatory structures that provide oversight for virological research in the United States. By offering our expertise, we - a broad group of working virologists - seek to aid policy makers in navigating these controversial issues. Balanced, evidence-based discourse is essential to addressing public concern while maintaining and expanding much-needed research in virology.


Asunto(s)
Investigación , Virología , Virosis , Humanos , COVID-19/prevención & control , Difusión de la Información , Pandemias/prevención & control , Formulación de Políticas , Investigación/normas , Investigación/tendencias , SARS-CoV-2 , Virología/normas , Virología/tendencias , Virosis/prevención & control , Virosis/virología , Virus
15.
mBio ; 14(1): e0018823, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36700642

RESUMEN

Viruses have brought humanity many challenges: respiratory infection, cancer, neurological impairment and immunosuppression to name a few. Virology research over the last 60+ years has responded to reduce this disease burden with vaccines and antivirals. Despite this long history, the COVID-19 pandemic has brought unprecedented attention to the field of virology. Some of this attention is focused on concern about the safe conduct of research with human pathogens. A small but vocal group of individuals has seized upon these concerns - conflating legitimate questions about safely conducting virus-related research with uncertainties over the origins of SARS-CoV-2. The result has fueled public confusion and, in many instances, ill-informed condemnation of virology. With this article, we seek to promote a return to rational discourse. We explain the use of gain-of-function approaches in science, discuss the possible origins of SARS-CoV-2 and outline current regulatory structures that provide oversight for virological research in the United States. By offering our expertise, we - a broad group of working virologists - seek to aid policy makers in navigating these controversial issues. Balanced, evidence-based discourse is essential to addressing public concern while maintaining and expanding much-needed research in virology.


Asunto(s)
COVID-19 , Infecciones del Sistema Respiratorio , Virus , Humanos , COVID-19/prevención & control , SARS-CoV-2 , Pandemias/prevención & control , Virus/genética
16.
mSphere ; 8(2): e0003423, 2023 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-36700653

RESUMEN

Viruses have brought humanity many challenges: respiratory infection, cancer, neurological impairment and immunosuppression to name a few. Virology research over the last 60+ years has responded to reduce this disease burden with vaccines and antivirals. Despite this long history, the COVID-19 pandemic has brought unprecedented attention to the field of virology. Some of this attention is focused on concern about the safe conduct of research with human pathogens. A small but vocal group of individuals has seized upon these concerns - conflating legitimate questions about safely conducting virus-related research with uncertainties over the origins of SARS-CoV-2. The result has fueled public confusion and, in many instances, ill-informed condemnation of virology. With this article, we seek to promote a return to rational discourse. We explain the use of gain-of-function approaches in science, discuss the possible origins of SARS-CoV-2 and outline current regulatory structures that provide oversight for virological research in the United States. By offering our expertise, we - a broad group of working virologists - seek to aid policy makers in navigating these controversial issues. Balanced, evidence-based discourse is essential to addressing public concern while maintaining and expanding much-needed research in virology.


Asunto(s)
COVID-19 , Virus , Humanos , COVID-19/prevención & control , SARS-CoV-2 , Pandemias/prevención & control , Antivirales
17.
J Virol ; 96(18): e0125522, 2022 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-36069547

RESUMEN

Eight infectious bursal disease virus (IBDV) genogroups have been identified based on the sequence of the capsid hypervariable region (HVR) (A1 to A8). Given reported vaccine failures, there is a need to evaluate the ability of vaccines to neutralize the different genogroups. To address this, we used a reverse genetics system and the chicken B-cell line DT40 to rescue a panel of chimeric IBDVs and perform neutralization assays. Chimeric viruses had the backbone of a lab-adapted strain (PBG98) and the HVRs from diverse field strains as follows: classical F52-70 (A1), U.S. variant Del-E (A2), Chinese variant SHG19 (A2), very virulent UK661 (A3), M04/09 distinct (A4), Italian ITA-04 (A6), and Australian variant Vic-01/94 (A8). Rescued viruses showed no substitutions at amino acid positions 253, 284, or 330, previously found to be associated with cell-culture adaptation. Sera from chickens inoculated with wild-type (wt) (F52-70) or vaccine (228E) A1 strains had the highest mean virus neutralization (VN) titers against the A1 virus (log2 15.4 and 12.7) and the lowest against A2 viruses (log2 7.4 to 7.9; P = 0.0001 to 0.0274), consistent with A1 viruses being most antigenically distant from A2 strains, which correlated with the extent of differences in the predicted HVR structure. VN titers against the other genogroups ranged from log2 9.3 to 13.3, and A1 strains were likely more closely antigenically related to genogroups A3 and A4 than A6 and A8. Our data are consistent with field observations and validate the new method, which can be used to screen future vaccine candidates for breadth of neutralizing antibodies and evaluate the antigenic relatedness of different genogroups. IMPORTANCE There is a need to evaluate the ability of vaccines to neutralize diverse IBDV genogroups and to better understand the relationship between HVR sequence, structure, and antigenicity. Here, we used a chicken B-cell line to rescue a panel of chimeric IBDVs with the HVR from seven diverse IBDV field strains and to conduct neutralization assays and protein modeling. We evaluated the ability of sera from vaccinated or infected birds to neutralize the different genogroups. Our novel chicken B-cell rescue system and neutralization assay can be used to screen IBDV vaccine candidates, platforms, and regimens for the breadth of neutralizing antibody responses elicited, evaluate the antigenic relatedness of diverse IBDV strains, and when coupled with structural modeling, elucidate immunodominant and conserved epitopes to strategically design novel IBDV vaccines in the future.


Asunto(s)
Anticuerpos Neutralizantes , Infecciones por Birnaviridae , Virus de la Enfermedad Infecciosa de la Bolsa , Enfermedades de las Aves de Corral , Animales , Australia , Infecciones por Birnaviridae/inmunología , Infecciones por Birnaviridae/virología , Pollos , Epítopos , Genotipo , Enfermedades de las Aves de Corral/inmunología
18.
J Virol ; 96(6): e0202421, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35138130

RESUMEN

To gain more information about the nature of Birnaviridae virus factories (VFs), we used a recombinant infectious bursal disease virus (IBDV) expressing split-GFP11 tagged to the polymerase (VP1) that we have previously shown is a marker for VFs in infected cells expressing GFP1-10. We found that VFs colocalized with 5-ethynyl uridine in the presence of actinomycin, demonstrating they contained newly synthesized viral RNA, and VFs were visible in infected cells that were fixed and permeabilized with digitonin, demonstrating that they were not membrane bound. Fluorescence recovery after photobleaching (FRAP) a region of interest within the VFs occurred rapidly, recovering from approximately 25% to 87% the original intensity over 146 s, and VFs were dissolved by 1,6-hexanediol treatment, demonstrating they showed properties consistent with liquid-liquid phase separation. There was a lower colocalization of the VF GFP signal with the capsid protein VP2 (Manders' coefficient [MC] 0.6), compared to VP3 (MC, 0.9), which prompted us to investigate the VF ultrastructure by transmission electron microscopy (TEM). In infected cells, paracrystalline arrays (PAs) of virions were observed in the cytoplasm, as well as discrete electron dense regions. Using correlative light and electron microscopy (CLEM), we observed that the electron dense regions correlated with the GFP signal of the VFs, which were distinct from the PAs. In summary, Birnaviridae VFs contain newly synthesized viral RNA, are not bound by a membrane, show properties consistent with liquid-liquid phase separation, and are distinct from the PAs observed by TEM. IMPORTANCE Members of the Birnaviridae infect birds, fish and insects, and are responsible for diseases of significant economic importance to the poultry industry and aquaculture. Despite their importance, how they replicate in cells remains poorly understood. Here, we show that the Birnaviridae virus factories are not membrane bound, demonstrate properties consistent with liquid-liquid phase separation, and are distinct from the paracrystalline arrays of virions observed by transmission electron microscopy, enhancing our fundamental knowledge of virus replication that could be used to develop strategies to control disease, or optimize their therapeutic application.


Asunto(s)
Infecciones por Birnaviridae , Birnaviridae , Virus de la Enfermedad Infecciosa de la Bolsa , Enfermedades de las Aves de Corral , Compartimentos de Replicación Viral , Replicación Viral , Animales , Birnaviridae/fisiología , Línea Celular , Pollos/genética , Virus de la Enfermedad Infecciosa de la Bolsa/fisiología , Microscopía Electrónica , ARN Viral/genética , Proteínas Estructurales Virales/metabolismo , Virión/metabolismo
19.
Viruses ; 15(1)2022 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-36680169

RESUMEN

Infectious bursal disease virus (IBDV) vaccines do not induce sterilizing immunity, and vaccinated birds can become infected with field strains. Vaccine-induced immune selection pressure drives the evolution of antigenic drift variants that accumulate amino acid changes in the hypervariable region (HVR) of the VP2 capsid, which may lead to vaccine failures. However, there is a lack of information regarding how quickly mutations arise, and the relative contribution different residues make to immune escape. To model IBDV antigenic drift in vitro, we serially passaged a classical field strain belonging to genogroup A1 (F52/70) ten times, in triplicate, in the immortalized chicken B cell line, DT40, in the presence of sub-neutralizing concentrations of sera from birds inoculated with IBDV vaccine strain 2512, to generate escape mutants. This assay simulated a situation where classical strains may infect birds that have suboptimal vaccine-induced antibody responses. We then sequenced the HVR of the VP2 capsid at passage (P) 5 and 10 and compared the sequences to the parental virus (P0), and to the virus passaged in the presence of negative control chicken serum that lacked IBDV antibodies. Two escape mutants at P10 had the same mutations, D279Y and G281R, and a third had mutations S251I and D279N. Furthermore, at P5, the D279Y mutation was detectable, but the G281R mutation was not, indicating the mutations arose with different kinetics.


Asunto(s)
Infecciones por Birnaviridae , Virus de la Enfermedad Infecciosa de la Bolsa , Enfermedades de las Aves de Corral , Vacunas Virales , Animales , Virus de la Enfermedad Infecciosa de la Bolsa/genética , Deriva y Cambio Antigénico , Pollos , Proteínas de la Cápside/genética
20.
J Telemed Telecare ; 27(10): 625-630, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34726990

RESUMEN

Telepalliative care services enable clinicians to provide essential palliation services to people with a life-limiting illness in or closer to home. This study aims to explore the costs, service activity and staff experiences resulting from the introduction of telehealth in a community palliative care service in Queensland, Australia. Pre- and post-activity and cost data from the 2016-2017 and 2019-2020 financial years were examined and staff members interviewed. Accounting for inflation and standard wage increases, the labour costs before and after the addition of telehealth were approximately equal. There were small variations in non-labour costs, but these were not directly attributable to the expansion of the telehealth services. Overall, the service activity increased by 189% for standard doctor and nurse consultations, due to the increased efficiency of telehealth compared to the previous outreach (travel) model. Thematic analysis of the staff interview data generated an overarching theme of Increased Job Satisfaction which staff attributed to the patient-centred nature of the telepalliative care service, the increased peer support and increased professional development. Compared with the traditional in-person service, the new telehealth-supported model resulted in equivalent costs, greater efficiency by allowing palliative care to reach more patients and improved staff job satisfaction.


Asunto(s)
Servicios de Salud Comunitaria , Cuidados Paliativos , Telemedicina , Australia , Humanos , Satisfacción en el Trabajo , Queensland
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