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1.
Front Vet Sci ; 11: 1384858, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38496315
2.
J Neurovirol ; 30(1): 39-51, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38172412

RESUMO

Sarbecoviruses such as SARS and SARS-CoV-2 have been responsible for two major outbreaks in humans, the latter resulting in a global pandemic. While sarbecoviruses primarily cause an acute respiratory infection, they have been shown to infect the nervous system. However, mechanisms of sarbecovirus neuroinvasion and neuropathogenesis remain unclear. In this study, we examined the infectivity and trans-synaptic transmission potential of the sarbecoviruses SARS and SARS-CoV-2 in human stem cell-derived neural model systems. We demonstrated limited ability of sarbecoviruses to infect and replicate in human stem cell-derived neurons. Furthermore, we demonstrated an inability of sarbecoviruses to transmit between synaptically connected human stem cell-derived neurons. Finally, we determined an absence of SARS-CoV-2 infection in olfactory neurons in experimentally infected ferrets. Collectively, this study indicates that sarbecoviruses exhibit low potential to infect human stem cell-derived neurons, lack an ability to infect ferret olfactory neurons, and lack an inbuilt molecular mechanism to utilise retrograde axonal trafficking and trans-synaptic transmission to spread within the human nervous system.


Assuntos
Axônios , COVID-19 , Furões , SARS-CoV-2 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Humanos , SARS-CoV-2/patogenicidade , SARS-CoV-2/fisiologia , Animais , COVID-19/virologia , COVID-19/transmissão , Axônios/virologia , Furões/virologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/patogenicidade , Neurônios/virologia , Replicação Viral , Chlorocebus aethiops , Células-Tronco Neurais/virologia , Células Vero
3.
Viruses ; 15(12)2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-38140648

RESUMO

Henipaviruses are zoonotic viruses, including some highly pathogenic and capable of serious disease and high fatality rates in both animals and humans. Hendra virus and Nipah virus are the most notable henipaviruses, resulting in significant outbreaks across South Asia, South-East Asia, and Australia. Pteropid fruit bats have been identified as key zoonotic reservoirs; however, the increased discovery of henipaviruses outside the geographic distribution of Pteropid fruit bats and the detection of novel henipa-like viruses in other species such as the shrew, rat, and opossum suggest that Pteropid bats are not the sole reservoir for henipaviruses. In this review, we provide an update on henipavirus spillover events and describe the recent detection of novel unclassified henipaviruses, with a strong focus on the shrew and its emerging role as a key host of henipaviruses.


Assuntos
Quirópteros , Vírus Hendra , Infecções por Henipavirus , Vírus Nipah , Humanos , Animais , Ratos , Infecções por Henipavirus/epidemiologia , Infecções por Henipavirus/veterinária , Musaranhos
4.
Trials ; 24(1): 506, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553645

RESUMO

BACKGROUND: Clinical equipoise, also defined as the uncertainty principle, is considered essential when recruiting subjects to a clinical trial. However, equipoise is threatened when clinicians are influenced by their own preferences. Little research has investigated equipoise in the context of trial recruitment. METHODS: This cross-sectional survey sought clinicians' views (operationalised as 11 statements relating to treatments offered in a trial of a psychological intervention for young people) about equipoise and individual treatment preferences in the context of moral justification for recruiting young people at risk of self-harm or suicide to a randomised controlled trial (RCT) to evaluate the Youth Culturally Adapted Manual Assisted Psychological Intervention (Y-CMAP) in Pakistan. We compared the views of clinicians involved in Y-CMAP RCT recruitment to those of a sample of clinicians not involved in trial recruitment but treating similar patients, comparing their sociodemographic characteristics and the proportions of those in each group agreeing with each statement. RESULTS: There was a response rate of 96% (75/78). Findings showed that, during trial recruitment and before the RCT results were known, the majority of all responding clinicians (73.3%) considered Y-CMAP to be an effective treatment for young people at risk of self-harm or suicide. Although there was an acknowledgement of individual preferences for the intervention, there was near consensus (90%) on the need to conduct an RCT for reaching an evidence-based decision. However, there were no significant differences in the proportion of recruiting clinicians reporting a treatment preference for Y-CMAP than non-recruiting clinicians (31 (88.6%) versus 36 (90%), p = 0.566). A significantly higher proportion of non-recruiting clinicians (87.5%) as compared to (48.5%) in the trial (p = 0.000) stated that there may be other treatments that may be equally good for the patients, seemingly undermining a preference for the intervention. Those reporting a treatment preference also acknowledged that there was nothing on which this preference was based, however confident they felt about them, thus accepting clinical equipoise as ethical justification for conducting the RCT. There was a significant group difference in views that treatment overall is better as a result of young patients' participation in the Y-CMAP trial (p = 0.015) (i.e. more clinicians not involved in the trial agreed with this statement). Similarly, more clinicians not involved in the trial agreed on the perceived availability of other treatment options that were good for young people at risk of self-harm (p < 0.05). CONCLUSIONS: The paper highlights that clinicians in Pakistan accept the notion of clinical equipoise as an ethical justification for patient participation in RCTs. The need for conducting RCTs to generate evidence base and to reduce bias was considered important by the clinical community.


Assuntos
Comportamento Autodestrutivo , Adolescente , Humanos , Paquistão , Seleção de Pacientes , Incerteza , Resultado do Tratamento , Comportamento Autodestrutivo/diagnóstico , Comportamento Autodestrutivo/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
Virology ; 587: 109856, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37541184

RESUMO

Hendra virus (HeV) and Nipah virus (NiV) are henipaviruses that can cause fatal encephalitis in humans. Many animal models have been used to study henipavirus pathogenesis. In the mouse, HeV infection has previously shown that intranasal challenge can lead to neurological infection, however mice similarly challenged with NiV show no evidence of virus infecting the brain. We generated recombinant HeV (rHeV) and NiV (rNiV) where selected proteins were switched to examine their role in neuroinvasion in the mouse. These viruses displayed similar growth kinetics when compared to wildtype in vitro. In the mouse, infection outcomes with recombinant virus did not differ to infection outcomes of wildtype viruses. Virus was detected in the brain of 5/30 rHeV-challenged mice, but not rNiV-challenged mice. To confirm the permissiveness of mouse neurons to these viruses, primary mouse neurons were successfully infected in vitro, suggesting that other pathobiological factors contribute to the differences in disease outcomes in mice.

6.
PLOS Glob Public Health ; 3(3): e0001250, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36962987

RESUMO

This aim of this scoping review is to map what is known about perceived coercion, perceived pressures and procedural justice within the context of the general population's experience of 'lockdowns' imposed by governments worldwide in response to the increased transmission of COVID-19. Arksey & O'Malley's (2005) framework for conducting scoping reviews was chosen. A sensitive search strategy was devised and conducted using PubMed, Scopus, and Web of Science using the following search terms: (adherence OR acceptance OR agreement OR trust OR distrust OR compliance OR willing*) OR (perceived coerc* OR percept* coerc* OR pressure OR force OR influence OR control OR threat OR justice) AND (lockdown) AND (COVID OR SARS-CoV-2 OR COVID-19). The database search initially produced 41,628 articles to screen. A total of 40 articles were included in this review and the following five themes were identified from the studies: perceived acceptability and willingness to adhere to lockdown; perceived control during lockdown; perceived pressures arising from lockdown; perceived threat of sanction from others and the procedural (in)justice of lockdown. Our synthesis suggests that i) individuals experienced an initial willingness and tolerance of lockdown that lessened over time as perceptions of personal control decreased; ii) that social influences may pressure individuals to follow or break lockdown rules; and iii) that justifiability and proportionality together with individuals' perceptions of harm from COVID-19 may impact the extent to which individuals adhere to lockdown. Furthermore, the review found an absence of information regarding specific individual characteristics and circumstances that increase the likelihood of experiencing perceived coercion and its related constructs and highlights a need for a better understanding of the cultural and socioeconomic factors affecting perceptions of, and adherence to, lockdown.

7.
Dev World Bioeth ; 23(3): 242-251, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35944158

RESUMO

The COVID-19 pandemic has reinforced the critical role of ethics and community engagement in designing and conducting clinical research during infectious disease outbreaks where no vaccine or treatment already exists. In reviewing current practices across Africa, we distinguish between three distinct roles for community engagement in clinical research that are often conflated: 1) the importance of community engagement for identifying and honouring cultural sensitivities; 2) the importance of recognising the socio-political context in which the research is proposed; and 3) the importance of understanding what is in the interest of communities recruited to research according to their own views and values. By making these distinctions, we show that current practice of clinical research could draw on anthropology in ways which are sometimes unnecessary to solicit local cultural values, overlook the importance of socio-political contexts and wider societal structures within which it works, potentially serving to reinforce unjust political or social regimes, and threaten to cast doubt on the trustworthiness of the research. We argue that more discerning anthropological engagement as well as wider collaboration with other social scientists and those working in the humanities is urgently needed to improve the ethics of current biomedical and pharmaceutical research practice in Africa.


Assuntos
COVID-19 , Pandemias , Humanos , África , Antropologia , Surtos de Doenças , Pandemias/prevenção & controle , Ensaios Clínicos como Assunto
8.
J Virol Methods ; 298: 114287, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34530012

RESUMO

Henipaviruses, Hendra (HeV) and Nipah (NiV), are highly pathogenic zoonotic agents that pose a serious health risk to human life, and as such are restricted to physical containment 4 (PC4) laboratories. For further analysis of virus-infected biological specimens, it is necessary to ensure absolute inactivation of any infectious virus present before removal from the PC4 laboratory. To evaluate the inactivation of HeV and NiV within infected samples, two chemical inactivation methods were assessed. Henipavirus-infected cell monolayers treated with 4 % paraformaldehyde (PFA) showed the complete inactivation of infectious virus, with an inactivation period of 15 min resulting in more than 8-log decrease in infectious titre. NiV-infected tissue samples treated with 10 % neutral-buffered formalin (NBF) showed a complete reduction of infectious virus in 7/8 ferret organs incubated for 24 h, with the remaining tissue demonstrating complete virus inactivation after 48 h. The chemical inactivation methods described herein evaluated two simple methods of henipavirus inactivation, resulting in the complete inactivation of infectious virus - an essential requirement for the safe removal and handling of biological samples from the PC4 laboratory.


Assuntos
Vírus Hendra , Infecções por Henipavirus , Henipavirus , Vírus Nipah , Animais , Contenção de Riscos Biológicos , Furões , Infecções por Henipavirus/prevenção & controle , Infecções por Henipavirus/veterinária , Humanos , Laboratórios , Vírus Nipah/fisiologia
10.
BMC Med Ethics ; 22(1): 47, 2021 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902560

RESUMO

Efforts to build research capacity and capability in low and middle income countries (LMIC) has progressed over the last three decades, yet it confronts many challenges including issues with communicating or even negotiating across different cultures. Implementing global research requires a broader understanding of community engagement and participatory research approaches. There is a considerable amount of guidance available on community engagement in clinical trials, especially for studies for HIV/AIDS, even culturally specific codes for recruiting vulnerable populations such as the San or Maori people. However, the same cannot be said for implementing research in global health. In an effort to build on this work, the Pakistan Institute of Living and Learning and University College London in the UK sought to better understand differences in beliefs, values and norms of local communities in Pakistan. In particular, they have sought to help researchers from high income countries (HIC) understand how their values are perceived and understood by the local indigenous researchers in Pakistan. To achieve this end, a group discussion was organised with indigenous researchers at Pakistan Institute of Living and Learning. The discussion will ultimately help inform the development of a cultural protocol for researchers from HIC engaging with communities in LMIC. This discussion revealed five common themes; (1) religious principles and rules, (2) differing concepts of and moral emphasis on autonomy and privacy, (3) importance of respect and trust; (4) cultural differences (etiquette); (5) custom and tradition (gift giving and hospitality). Based on the above themes, we present a preliminary cultural analysis to raise awareness and to prepare researchers from HIC conducting cross cultural research in Pakistan. This is likely to be particularly relevant in collectivistic cultures where social interconnectedness, family and community is valued above individual autonomy and the self is not considered central to moral thinking. In certain cultures, HIC ideas of individual autonomy, the notion of informed consent may be regarded as a collective family decision. In addition, there may still be acceptance of traditional professional roles such as 'doctor knows best', while respect and privacy may have very different meanings.


Assuntos
Bioética , Pesquisa Participativa Baseada na Comunidade/ética , Cultura , Saúde Global , Pesquisadores/ética , Participação da Comunidade , Humanos , Consentimento Livre e Esclarecido , Londres , Paquistão , Confiança
13.
Lancet Infect Dis ; 19(12): e444-e451, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31451421

RESUMO

Antimicrobial resistance is one of the most important threats to global health security. A range of Gram-negative bacteria associated with high morbidity and mortality are now resistant to almost all available antibiotics. In this context of urgency to develop novel drugs, new antibiotics for multidrug-resistant Gram-negative bacteria (namely, ceftazidime-avibactam, plazomicin, and meropenem-vaborbactam) have been approved by regulatory authorities based on non-inferiority trials that provided no direct evidence of their efficacy against multidrug-resistant bacteria such as Enterobacteriaceae spp, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Burkholderia cepacia, and Acinetobacter baumannii. The use of non-inferiority and superiority trials, and selection of appropriate and optimal study designs, remains a major challenge in the development, registration, and post-marketing implementation of new antibiotics. Using an example of the development process of ceftazidime-avibactam, we propose a strategy for a new research framework based on adaptive randomised clinical trials. The operational research strategy has the aim of assessing the efficacy of new antibiotics in special groups of patients, such as those infected with multidrug-resistant bacteria, who were not included in earlier phase studies, and for whom it is important to establish an appropriate standard of care.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Humanos , Testes de Sensibilidade Microbiana , Vigilância de Produtos Comercializados , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
BMJ Case Rep ; 12(1)2019 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-30700464

RESUMO

We present a first case of synovial sarcoma in an HIV-positive pregnant woman. This 28-year-old woman was diagnosed with synovial sarcoma, a high-grade malignant soft tissue sarcoma, involving her left thigh during the first trimester of her pregnancy. She underwent surgical treatment in the form of hip disarticulation at 30 weeks' gestation. She was subsequently delivered by emergency caesarean section (CS) at 34 weeks' gestation when she presented with wound sepsis and a scan revealed static growth in a small for gestational age fetus. Prompt diagnosis and treatment of this aggressive tumour is important and should involve a multidisciplinary approach, with a balanced consideration of the maternal and fetal outcomes.


Assuntos
Infecções por HIV/complicações , Complicações Neoplásicas na Gravidez/diagnóstico , Sarcoma Sinovial/complicações , Sarcoma Sinovial/diagnóstico , Adulto , Cesárea , Diagnóstico Diferencial , Feminino , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Gravidez , Complicações Neoplásicas na Gravidez/cirurgia , Sarcoma Sinovial/cirurgia , Coxa da Perna/diagnóstico por imagem , Coxa da Perna/cirurgia
16.
Am J Bioeth ; 18(10): 35-42, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30339070

RESUMO

As the usual regulatory framework did not fit well during the last Ebola outbreak, innovative thinking still needed. In the absence of an outbreak, randomised controlled trials of clinical efficacy in humans cannot be done, while during an outbreak such trials will continue to face significant practical, philosophical, and ethical challenges. This article argues that researchers should also test the safety and effectiveness of novel vaccines in wild apes by employing a pluralistic approach to evidence. There are three reasons to test vaccines in wild populations of apes: i) protect apes; ii) reduce Ebola transmission from wild animals to humans; and iii) accelerate vaccine development and licensing for humans. Data obtained from studies of vaccines among wild apes and chimpanzees may even be considered sufficient for licensing new vaccines for humans. This strategy will serve to benefit both wild apes and humans.


Assuntos
Pesquisa Biomédica/ética , Controle de Doenças Transmissíveis/métodos , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Vacinas contra Ebola/administração & dosagem , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/veterinária , Zoonoses/prevenção & controle , Animais , Animais Selvagens/virologia , Doenças dos Símios Antropoides/virologia , Surtos de Doenças/ética , Monitoramento Epidemiológico/veterinária , Revisão Ética , Ética em Pesquisa , Gorilla gorilla/virologia , Doença pelo Vírus Ebola/tratamento farmacológico , Doença pelo Vírus Ebola/imunologia , Humanos , Saúde Pública , Vacinação/ética
18.
Trials ; 17(1): 431, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27590594

RESUMO

BACKGROUND: Randomised controlled trials (RCTs) often fail to recruit sufficient participants, despite altruism being cited as their motivation. Previous investigations of factors influencing participation decisions have been methodologically limited. This study evaluated how women weigh up different motivations after initially expressing altruism, and explored their understanding of a trial and its alternatives. The trial was the 'Quality of Life after Mastectomy and Breast Reconstruction' (QUEST) trial. METHODS: Thirty-nine women participated in qualitative interviews 1 month post-surgery. Twenty-seven women (10 trial decliners and 17 acceptors) who spontaneously mentioned 'altruism' were selected for thematic analysis. Verbatim transcripts were coded independently by two researchers. Participants' motivations to accept or decline randomisation were cross-referenced with their understanding of the QUEST trials and the process of randomisation. RESULTS: The seven emerging themes were: (1) altruism expressed by acceptors and decliners; (2) overriding personal needs in decliners; (3) pure altruism in acceptors; (4) 'hypothetical altruism' amongst acceptors; (5) weak altruism amongst acceptors; (6) conditional altruism amongst acceptors; and (7) sense of duty to participate. Poor understanding of the trial rationale and its implications was also evident. CONCLUSIONS: Altruism was a motivating factor for participation in the QUEST randomised controlled trials where the main outcomes comprised quality of life and allocated treatments comprised established surgical procedures. Women's decisions were influenced by their understanding of the trial. Both acceptors and decliners of the trial expressed 'altruism', but most acceptors lacked an obvious treatment preference, hoped for personal benefits regarding a treatment allocation, or did not articulate complete understanding of the trial. TRIAL REGISTRATION: QUEST A, ISRCTN38846532 ; Date assigned 6 January 2010. QUEST B, ISRCTN92581226 ; Date assigned 6 January 2010.


Assuntos
Altruísmo , Neoplasias da Mama/cirurgia , Ensaios Clínicos como Assunto , Consentimento Livre e Esclarecido , Mamoplastia , Mastectomia , Aceitação pelo Paciente de Cuidados de Saúde , Sujeitos da Pesquisa/psicologia , Adulto , Neoplasias da Mama/patologia , Neoplasias da Mama/psicologia , Compreensão , Feminino , Humanos , Entrevistas como Assunto , Mamoplastia/efeitos adversos , Mamoplastia/psicologia , Mastectomia/efeitos adversos , Mastectomia/psicologia , Pessoa de Meia-Idade , Motivação , Pesquisa Qualitativa , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo , Resultado do Tratamento
19.
Trials ; 17: 166, 2016 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-27020947

RESUMO

BACKGROUND: There is growing interest in the ethics of cluster trials, but no literature on the uncertainties in defining communities in relation to the scientific notion of the cluster in collaborative biomedical research. METHODS: The views of participants in a community-based cluster randomised trial (CRT) in Mumbai, India, were solicited regarding their understanding and views on community. We conducted two focus group discussions with local residents and 20 semi-structured interviews with different respondent groups. On average, ten participants took part in each focus group, most of them women aged 18-55. We conducted semi-structured interviews with ten residents (nine women and one man) lasting approximately an hour each and seven individuals (five men and two women) identified by residents as local leaders or decision-makers. In addition, we interviewed two Municipal Corporators (locally elected government officials involved in urban planning and development) and one representative of a political party located in a slum community. RESULTS: Residents' sense of community largely matched the scientific notion of the cluster, defined by the investigators as a geographic area, but their perceived needs were not entirely met by the trial. CONCLUSION: We examined whether the possibility of a conceptual mismatch between 'clusters' and 'communities' is likely to have methodological implications for a study or to lead to potential social disharmony because of the research interventions, arguing that it is important to take social factors into account as well as statistical efficiency when choosing the size and type of clusters and designing a trial. One method of informing such a design would be to use existing forums for community engagement to explore individuals' primary sense of community or social group and, where possible, to fit clusters around them. TRIAL REGISTRATION: ISRCTN Register: ISRCTN56183183 Clinical Trials Registry of India: CTRI/2012/09/003004 .


Assuntos
Serviços de Saúde Comunitária , Relações Comunidade-Instituição , Conhecimentos, Atitudes e Prática em Saúde , Percepção , Áreas de Pobreza , Projetos de Pesquisa , Sujeitos da Pesquisa/psicologia , Adolescente , Adulto , Criança , Serviços de Saúde da Criança , Análise por Conglomerados , Feminino , Grupos Focais , Humanos , Índia , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Terapia Nutricional , Participação do Paciente , Serviços de Saúde da Mulher , Adulto Jovem
20.
Philos Trans A Math Phys Eng Sci ; 373(2042)2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25897085

RESUMO

Magnetic fields permeate the entire solar atmosphere weaving an extremely complex pattern on both local and global scales. In order to understand the nature of this tangled web of magnetic fields, its magnetic skeleton, which forms the boundaries between topologically distinct flux domains, may be determined. The magnetic skeleton consists of null points, separatrix surfaces, spines and separators. The skeleton is often used to clearly visualize key elements of the magnetic configuration, but parts of the skeleton are also locations where currents and waves may collect and dissipate. In this review, the nature of the magnetic skeleton on both global and local scales, over solar cycle time scales, is explained. The behaviour of wave pulses in the vicinity of both nulls and separators is discussed and so too is the formation of current layers and reconnection at the same features. Each of these processes leads to heating of the solar atmosphere, but collectively do they provide enough heat, spread over a wide enough area, to explain the energy losses throughout the solar atmosphere? Here, we consider this question for the three different solar regions: active regions, open-field regions and the quiet Sun. We find that the heating of active regions and open-field regions is highly unlikely to be due to reconnection or wave dissipation at topological features, but it is possible that these may play a role in the heating of the quiet Sun. In active regions, the absence of a complex topology may play an important role in allowing large energies to build up and then, subsequently, be explosively released in the form of a solar flare. Additionally, knowledge of the intricate boundaries of open-field regions (which the magnetic skeleton provides) could be very important in determining the main acceleration mechanism(s) of the solar wind.

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