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1.
Front Immunol ; 15: 1334236, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38444847

RESUMO

Introduction: Initiation of antiretroviral treatment (ART) in patients early after HIV-infection and long-term suppression leads to low or undetectable levels of HIV RNA and cell-associated (CA) HIV DNA and RNA. Both CA-DNA and CA-RNA, overestimate the size of the HIV reservoir but CA-RNA as well as p24/cell-free viral RNA can be indicators of residual viral replication. This study describes HIV RNA amounts and levels of cytokines/soluble markers in 40 well-suppressed adolescents who initiated ART early in life and investigated which viral markers may be informative as endpoints in cure clinical trials within this population. Methods: Forty adolescents perinatally infected with HIV on suppressive ART for >5 years were enrolled in the CARMA study. HIV DNA and total or unspliced CA-RNA in PBMCs were analyzed by qPCR/RT-qPCR and dPCR/RT-dPCR. Cell-free HIV was determined using an ultrasensitive viral load (US-VL) assay. Plasma markers and p24 were analyzed by digital ELISA and correlations between total and unspliced HIV RNA and clinical markers, including age at ART, Western Blot score, levels of cytokines/inflammation markers or HIV CA-DNA, were tested. Results: CA-RNA was detected in two thirds of the participants and was comparable in RT-qPCR and RT-dPCR. Adolescents with undetectable CA-RNA showed significantly lower HIV DNA compared to individuals with detectable CA-RNA. Undetectable unspliced CA-RNA was positively associated with age at ART initiation and Western Blot score. We found that a higher concentration of TNF-α was predictive of higher CA-DNA and CA-RNA. Other clinical characteristics like US-VL, time to suppression, or percent CD4+ T-lymphocytes were not predictive of the CA-RNA in this cross-sectional study. Conclusions: Low CA-DNA after long-term suppressive ART is associated with lower CA-RNA, in concordance with other reports. Patients with low CA-RNA levels in combination with low CA-DNA and low Western Blot scores should be further investigated to characterize candidates for treatment interruption trials. Unspliced CA-RNA warrants further investigation as a marker that can be prioritized in paediatric clinical trials where the sample volume can be a significant limitation.


Assuntos
Ácidos Nucleicos Livres , Infecções por HIV , Humanos , Adolescente , Criança , Estudos Transversais , RNA , Antirretrovirais/uso terapêutico , Citocinas , Infecções por HIV/tratamento farmacológico , DNA
2.
Can Med Educ J ; 14(4): 35-46, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37719396

RESUMO

Background: Training future doctors in the skills of evidence-based medicine (EBM) is clearly important. Journal club (JCs) are well-recognized educational interventions for teaching EBM. In contrast to postgraduate medical education, JCs use in undergraduate medical education (UME) has not been adequately explored. We conducted a realist review of the effectiveness of JCs in UME to unpack the underlying mechanisms by which the intervention works (or fails) in teaching EBM. Methods: The scope of review was the evaluation of the effectiveness of JCs in UME settings. We searched major bibliographic databases - MEDLINE, Embase, ERIC, PSYCInfo, CINAHL, Scopus, and Web of Science and found fifteen articles eligible for inclusion. Data was extracted aided by a modified Kirkpatrick framework and presented in evidence tables. Themes and chains of inference were identified, and finally, we formulated new hypotheses on how and why JC intervention works. Results: Mandatory vs. voluntary JC did not differentially impact attendance of JC in UME settings though JC duration beyond two hours decreased attendees' self-reported satisfaction. Coupling lectures to JCs positively impacts knowledge gain and retention. Coupled Mentorship or using critical appraisal worksheets helped the achievement of manuscript writing skills and a positive attitude towards EBM. Conclusions: Journal clubs are effective interventions to teach EBM in UME settings and are well-received by learners. They improve specific learning outcomes of knowledge gain and retention, skills of manuscript writing and critical appraisal. However, we found no evidence that these translates to the practice of EBM nor impacts patient outcomes.


Contexte: Il est important que les compétences enseignées aux futurs médecins soient conformes à l'approche de la médecine fondée sur les données probantes (MFDP) et les clubs de lecture (CL) sont reconnus comme une intervention pédagogique en ce sens. Le recours aux CL dans la formation prédoctorale a été peu étudié, contrairement à la place qu'ils occupent au postdoctorat. Nous avons effectué une revue réaliste de l'efficacité des CL dans la formation de premier cycle pour décortiquer les mécanismes sous-jacents qui déterminent la réussite ou l'échec de cette méthode pédagogique en ce qui a trait à l'enseignement de la MFDP. Méthodes: La revue visait l'évaluation de l'efficacité des CL dans la formation médicale prédoctroale. Nous avons effectué des recherches dans les principales banques de données bibliographiques ­ MEDLINE, Embase, ERIC, PSYCInfo, CINAHL, Scopus et Web of Science ­ et avons trouvé quinze articles répondant à nos critères d'inclusion. Nous avons utilisé le modèle modifié de Kirkpatrick pour la collecte de données, que nous avons présentées sous forme de tableaux de preuves. Nous avons dégagé des thèmes et élaboré des chaînes d'inférences, puis formulé de nouvelles hypothèses sur le comment et le pourquoi de l'efficacité des CL. Résultats: Le caractère obligatoire ou facultatif de l'activité n'a pas eu d'effet différentiel sur la participation des étudiants de premier cycle aux CL, mais leur satisfaction autodéclarée diminuait lorsque la durée de la séance dépassait deux heures. En revanche, le fait de conjuguer les CL à des conférences a eu un effet positif sur l'acquisition et la rétention des connaissances et le fait de les conjuguer au mentorat ou à l'utilisation de feuilles d'évaluation critique a contribué à l'acquisition de compétences en rédaction et à l'adoption par les étudiants d'une attitude positive à l'égard de la MFDP. Conclusions: Les clubs de lecture constituent un moyen efficace et bien accueilli par les apprenants pour enseigner la MFDP au prédoctorat. Ils améliorent les résultats d'apprentissage spécifiques sur le plan de l'acquisition et de la rétention des connaissances, ainsi que les compétences en matière de rédaction et d'évaluation critique. Toutefois, nous n'avons trouvé aucune indication que ces effets puissent se répercuter dans la pratique de la MFDP ou dans les résultats pour les patients.


Assuntos
Educação de Graduação em Medicina , Educação Médica , Humanos , Estudantes , Bases de Dados Bibliográficas , Medicina Baseada em Evidências
3.
Viruses ; 15(9)2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37766218

RESUMO

Modern HIV-1 treatment effectively suppresses viral amplification in people living with HIV. However, the persistence of HIV-1 DNA as proviruses integrated into the human genome remains the main barrier to achieving a cure. Next-generation sequencing (NGS) offers increased sensitivity for characterising archived drug resistance mutations (DRMs) in HIV-1 DNA for improved treatment options. In this study, we present an ultra-sensitive targeted PCR assay coupled with NGS and a robust pipeline to characterise HIV-1 DNA DRMs from buffy coat samples. Our evaluation supports the use of this assay for Pan-HIV-1 analyses with reliable detection of DRMs across the HIV-1 Pol region. We propose this assay as a new valuable tool for monitoring archived HIV-1 drug resistance in virologically suppressed individuals, especially in clinical trials investigating novel therapeutic approaches.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , HIV-1/genética , Infecções por HIV/tratamento farmacológico , Genótipo , Farmacorresistência Viral/genética , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Antirretrovirais/uso terapêutico , Mutação , Sequenciamento de Nucleotídeos em Larga Escala
5.
J Am Heart Assoc ; 11(19): e025914, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36073649

RESUMO

Background A recent randomized trial, the MICHELLE trial, demonstrated improved posthospital outcomes with a 35-day course of prophylactic rivaroxaban for patients hospitalized with COVID-19 at high risk of venous thromboembolism. We explored how often these findings may apply to an unselected clinical population of patients hospitalized with COVID-19. Methods and Results Using a 35-hospital retrospective cohort of patients hospitalized between March 7, 2020, and January 23, 2021, with COVID-19 (MI-COVID19 database), we quantified the percentage of hospitalized patients with COVID-19 who would be eligible for rivaroxaban at discharge per MICHELLE trial criteria and report clinical event rates. The main clinical outcome was derived from the MICHELLE trial and included a composite of symptomatic venous thromboembolism, pulmonary embolus-related death, nonhemorrhagic stroke, and cardiovascular death at 35 days. Multiple sensitivity analyses tested different eligibility and exclusion criteria definitions to determine the effect on eligibility for postdischarge anticoagulation prophylaxis. Of 2016 patients hospitalized with COVID-19 who survived to discharge and did not have another indication for anticoagulation, 25.9% (n=523) would be eligible for postdischarge thromboprophylaxis per the MICHELLE trial criteria (range, 2.9%-39.4% on sensitivity analysis). Of the 416 who had discharge anticoagulant data collected, only 13.2% (55/416) were actually prescribed a new anticoagulant at discharge. Of patients eligible for rivaroxaban per the MICHELLE trial, the composite clinical outcome occurred in 1.2% (6/519); similar outcome rates were 5.7% and 0.63% in the MICHELLE trial's control (no anticoagulation) and intervention (rivaroxaban) groups, respectively. Symptomatic venous thromboembolism events and all-cause mortality were 6.2% (32/519) and 5.66% in the MI-COVID19 and MICHELLE trial control cohorts, respectively. Conclusions Across 35 hospitals in Michigan, ≈1 in 4 patients hospitalized with COVID-19 would qualify for posthospital thromboprophylaxis. With only 13% of patients actually receiving postdischarge prophylaxis, there is a potential opportunity for improvement in care.


Assuntos
COVID-19 , Tromboembolia Venosa , Assistência ao Convalescente , Anticoagulantes/uso terapêutico , COVID-19/complicações , Humanos , Alta do Paciente , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Rivaroxabana/uso terapêutico , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle
6.
J Am Acad Child Adolesc Psychiatry ; 61(4): 495-507, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34597773

RESUMO

OBJECTIVE: A lack of universal definitions for response and remission in pediatric obsessive-compulsive disorder (OCD) has hampered the comparability of results across trials. To address this problem, we conducted an individual participant data diagnostic test accuracy meta-analysis to evaluate the discriminative ability of the Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) in determining response and remission. We also aimed to generate empirically derived cutoffs on the CY-BOCS for these outcomes. METHOD: A systematic review of PubMed, PsycINFO, Embase and CENTRAL identified 5,401 references; 42 randomized controlled clinical trials were considered eligible, and 21 provided data for inclusion (N = 1,234). Scores of ≤2 in the Clinical Global Impressions Improvement and Severity scales were chosen to define response and remission, respectively. A 2-stage, random-effects meta-analysis model was established. The area under the curve (AUC) and the Youden Index were computed to indicate the discriminative ability of the CY-BOCS and to guide for the optimal cutoff, respectively. RESULTS: The CY-BOCS had sufficient discriminative ability to determine response (AUC = 0.89) and remission (AUC = 0.92). The optimal cutoff for response was a ≥35% reduction from baseline to posttreatment (sensitivity = 83.9, 95% CI = 83.7-84.1; specificity = 81.7, 95% CI = 81.5-81.9). The optimal cutoff for remission was a posttreatment raw score of ≤12 (sensitivity = 82.0, 95% CI = 81.8-82.2; specificity = 84.6, 95% CI = 84.4-84.8). CONCLUSION: Meta-analysis identified empirically optimal cutoffs on the CY-BOCS to determine response and remission in pediatric OCD randomized controlled clinical trials. Systematic adoption of standardized operational definitions for response and remission will improve comparability across trials for pediatric OCD.


Assuntos
Transtorno Obsessivo-Compulsivo , Criança , Humanos , Transtorno Obsessivo-Compulsivo/diagnóstico , Transtorno Obsessivo-Compulsivo/tratamento farmacológico , Projetos de Pesquisa
7.
BMC Plant Biol ; 21(1): 316, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215204

RESUMO

BACKGROUND: Ergot, caused by the fungal pathogen Claviceps purpurea, infects the female flowers of a range of cereal crops, including wheat. To understand the interaction between C. purpurea and hexaploid wheat we undertook an extensive examination of the reprogramming of the wheat transcriptome in response to C. purpurea infection through floral tissues (i.e. the stigma, transmitting and base ovule tissues of the ovary) and over time. RESULTS: C. purpurea hyphae were observed to have grown into and down the stigma at 24 h (H) after inoculation. By 48H hyphae had grown through the transmitting tissue into the base, while by 72H hyphae had surrounded the ovule. By 5 days (D) the ovule had been replaced by fungal tissue. Differential gene expression was first observed at 1H in the stigma tissue. Many of the wheat genes differentially transcribed in response to C. purpurea infection were associated with plant hormones and included the ethylene (ET), auxin, cytokinin, gibberellic acid (GA), salicylic acid and jasmonic acid (JA) biosynthetic and signaling pathways. Hormone-associated genes were first detected in the stigma and base tissues at 24H, but not in the transmitting tissue. Genes associated with GA and JA pathways were seen in the stigma at 24H, while JA and ET-associated genes were identified in the base at 24H. In addition, several defence-related genes were differential expressed in response to C. purpurea infection, including antifungal proteins, endocytosis/exocytosis-related proteins, NBS-LRR class proteins, genes involved in programmed cell death, receptor protein kinases and transcription factors. Of particular interest was the identification of differential expression of wheat genes in the base tissue well before the appearance of fungal hyphae, suggesting that a mobile signal, either pathogen or plant-derived, is delivered to the base prior to colonisation. CONCLUSIONS: Multiple host hormone biosynthesis and signalling pathways were significantly perturbed from an early stage in the wheat - C. purpurea interaction. Differential gene expression at the base of the ovary, ahead of arrival of the pathogen, indicated the potential presence of a long-distance signal modifying host gene expression.


Assuntos
Claviceps/fisiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Transcriptoma/genética , Triticum/genética , Triticum/microbiologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Reguladores de Crescimento de Plantas/farmacologia , RNA-Seq , Fatores de Tempo , Triticum/efeitos dos fármacos
8.
Wellcome Open Res ; 6: 9, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34095506

RESUMO

The ongoing pandemic of SARS-CoV-2 calls for rapid and cost-effective methods to accurately identify infected individuals. The vast majority of patient samples is assessed for viral RNA presence by RT-qPCR. Our biomedical research institute, in collaboration between partner hospitals and an accredited clinical diagnostic laboratory, established a diagnostic testing pipeline that has reported on more than 252,000 RT-qPCR results since its commencement at the beginning of April 2020. However, due to ongoing demand and competition for critical resources, alternative testing strategies were sought. In this work, we present a clinically-validated procedure for high-throughput SARS-CoV-2 detection by RT-LAMP in 25 minutes that is robust, reliable, repeatable, sensitive, specific, and inexpensive.

9.
JAMA Netw Open ; 4(6): e2111788, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34115129

RESUMO

Importance: Venous thromboembolism (VTE) is a common complication of COVID-19. It is not well understood how hospitals have managed VTE prevention and the effect of prevention strategies on mortality. Objective: To characterize frequency, variation across hospitals, and change over time in VTE prophylaxis and treatment-dose anticoagulation in patients hospitalized for COVID-19, as well as the association of anticoagulation strategies with in-hospital and 60-day mortality. Design, Setting, and Participants: This cohort study of adults hospitalized with COVID-19 used a pseudorandom sample from 30 US hospitals in the state of Michigan participating in a collaborative quality initiative. Data analyzed were from patients hospitalized between March 7, 2020, and June 17, 2020. Data were analyzed through March 2021. Exposures: Nonadherence to VTE prophylaxis (defined as missing ≥2 days of VTE prophylaxis) and receipt of treatment-dose or prophylactic-dose anticoagulants vs no anticoagulation during hospitalization. Main Outcomes and Measures: The effect of nonadherence and anticoagulation strategies on in-hospital and 60-day mortality was assessed using multinomial logit models with inverse probability of treatment weighting. Results: Of a total 1351 patients with COVID-19 included (median [IQR] age, 64 [52-75] years; 47.7% women, 48.9% Black patients), only 18 (1.3%) had a confirmed VTE, and 219 (16.2%) received treatment-dose anticoagulation. Use of treatment-dose anticoagulation without imaging ranged from 0% to 29% across hospitals and increased over time (adjusted odds ratio [aOR], 1.46; 95% CI, 1.31-1.61 per week). Of 1127 patients who ever received anticoagulation, 392 (34.8%) missed 2 or more days of prophylaxis. Missed prophylaxis varied from 11% to 61% across hospitals and decreased markedly over time (aOR, 0.89; 95% CI, 0.82-0.97 per week). VTE nonadherence was associated with higher 60-day (adjusted hazard ratio [aHR], 1.31; 95% CI, 1.03-1.67) but not in-hospital mortality (aHR, 0.97; 95% CI, 0.91-1.03). Receiving any dose of anticoagulation (vs no anticoagulation) was associated with lower in-hospital mortality (only prophylactic dose: aHR, 0.36; 95% CI, 0.26-0.52; any treatment dose: aHR, 0.38; 95% CI, 0.25-0.58). However, only the prophylactic dose of anticoagulation remained associated with lower mortality at 60 days (prophylactic dose: aHR, 0.71; 95% CI, 0.51-0.90; treatment dose: aHR, 0.92; 95% CI, 0.63-1.35). Conclusions and Relevance: This large, multicenter cohort of patients hospitalized with COVID-19, found evidence of rapid dissemination and implementation of anticoagulation strategies, including use of treatment-dose anticoagulation. As only prophylactic-dose anticoagulation was associated with lower 60-day mortality, prophylactic dosing strategies may be optimal for patients hospitalized with COVID-19.


Assuntos
Anticoagulantes/uso terapêutico , COVID-19/complicações , Hospitalização/tendências , SARS-CoV-2 , Tromboembolia Venosa/prevenção & controle , Idoso , COVID-19/epidemiologia , Feminino , Mortalidade Hospitalar/tendências , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia
10.
Lancet Infect Dis ; 21(9): 1246-1256, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33857406

RESUMO

BACKGROUND: Emergence of variants with specific mutations in key epitopes in the spike protein of SARS-CoV-2 raises concerns pertinent to mass vaccination campaigns and use of monoclonal antibodies. We aimed to describe the emergence of the B.1.1.7 variant of concern (VOC), including virological characteristics and clinical severity in contemporaneous patients with and without the variant. METHODS: In this cohort study, samples positive for SARS-CoV-2 on PCR that were collected from Nov 9, 2020, for patients acutely admitted to one of two hospitals on or before Dec 20, 2020, in London, UK, were sequenced and analysed for the presence of VOC-defining mutations. We fitted Poisson regression models to investigate the association between B.1.1.7 infection and severe disease (defined as point 6 or higher on the WHO ordinal scale within 14 days of symptoms or positive test) and death within 28 days of a positive test and did supplementary genomic analyses in a cohort of chronically shedding patients and in a cohort of remdesivir-treated patients. Viral load was compared by proxy, using PCR cycle threshold values and sequencing read depths. FINDINGS: Of 496 patients with samples positive for SARS-CoV-2 on PCR and who met inclusion criteria, 341 had samples that could be sequenced. 198 (58%) of 341 had B.1.1.7 infection and 143 (42%) had non-B.1.1.7 infection. We found no evidence of an association between severe disease and death and lineage (B.1.1.7 vs non-B.1.1.7) in unadjusted analyses (prevalence ratio [PR] 0·97 [95% CI 0·72-1·31]), or in analyses adjusted for hospital, sex, age, comorbidities, and ethnicity (adjusted PR 1·02 [0·76-1·38]). We detected no B.1.1.7 VOC-defining mutations in 123 chronically shedding immunocompromised patients or in 32 remdesivir-treated patients. Viral load by proxy was higher in B.1.1.7 samples than in non-B.1.1.7 samples, as measured by cycle threshold value (mean 28·8 [SD 4·7] vs 32·0 [4·8]; p=0·0085) and genomic read depth (1280 [1004] vs 831 [682]; p=0·0011). INTERPRETATION: Emerging evidence exists of increased transmissibility of B.1.1.7, and we found increased virus load by proxy for B.1.1.7 in our data. We did not identify an association of the variant with severe disease in this hospitalised cohort. FUNDING: University College London Hospitals NHS Trust, University College London/University College London Hospitals NIHR Biomedical Research Centre, Engineering and Physical Sciences Research Council.


Assuntos
COVID-19/virologia , Genoma Viral , SARS-CoV-2/genética , Índice de Gravidade de Doença , Sequenciamento Completo do Genoma , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Londres , Masculino , Pessoa de Meia-Idade , Filogenia , Reino Unido , Carga Viral , Eliminação de Partículas Virais
11.
Mayo Clin Proc ; 96(5): 1342-1355, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33741131

RESUMO

The widespread use of complementary products poses a challenge to clinicians in the perioperative period and may increase perioperative risk. Because dietary supplements are regulated differently from traditional pharmaceuticals and guidance is often lacking, the Society for Perioperative Assessment and Quality Improvement convened a group of experts to review available literature and create a set of consensus recommendations for the perioperative management of these supplements. Using a modified Delphi method, the authors developed recommendations for perioperative management of 83 dietary supplements. We have made our recommendations to discontinue or continue a dietary supplement based on the principle that without a demonstrated benefit, or with a demonstrated lack of harm, there is little downside in temporarily discontinuing an herbal supplement before surgery. Discussion with patients in the preoperative visit is a crucial time to educate patients as well as gather vital information. Patients should be specifically asked about use of dietary supplements and cannabinoids, as many will not volunteer this information. The preoperative clinic visit provides the best opportunity to educate patients about the perioperative management of various supplements as this visit is typically scheduled at least 2 weeks before the planned procedure.


Assuntos
Suplementos Nutricionais , Complicações Intraoperatórias/prevenção & controle , Complicações Pós-Operatórias/prevenção & controle , Cuidados Pré-Operatórios/normas , Técnica Delphi , Suplementos Nutricionais/efeitos adversos , Humanos , Complicações Intraoperatórias/etiologia , Complicações Pós-Operatórias/etiologia , Cuidados Pré-Operatórios/métodos , Melhoria de Qualidade
12.
Nature ; 591(7850): 451-457, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33561864

RESUMO

All coronaviruses known to have recently emerged as human pathogens probably originated in bats1. Here we use a single experimental platform based on immunodeficient mice implanted with human lung tissue (hereafter, human lung-only mice (LoM)) to demonstrate the efficient in vivo replication of severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), as well as two endogenous SARS-like bat coronaviruses that show potential for emergence as human pathogens. Virus replication in this model occurs in bona fide human lung tissue and does not require any type of adaptation of the virus or the host. Our results indicate that bats contain endogenous coronaviruses that are capable of direct transmission to humans. Our detailed analysis of in vivo infection with SARS-CoV-2 in human lung tissue from LoM showed a predominant infection of human lung epithelial cells, including type-2 pneumocytes that are present in alveoli and ciliated airway cells. Acute infection with SARS-CoV-2 was highly cytopathic and induced a robust and sustained type-I interferon and inflammatory cytokine and chemokine response. Finally, we evaluated a therapeutic and pre-exposure prophylaxis strategy for SARS-CoV-2 infection. Our results show that therapeutic and prophylactic administration of EIDD-2801-an oral broad-spectrum antiviral agent that is currently in phase II/III clinical trials-markedly inhibited SARS-CoV-2 replication in vivo, and thus has considerable potential for the prevention and treatment of COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19/prevenção & controle , Citidina/análogos & derivados , Hidroxilaminas/administração & dosagem , Hidroxilaminas/uso terapêutico , Administração Oral , Células Epiteliais Alveolares/imunologia , Células Epiteliais Alveolares/patologia , Células Epiteliais Alveolares/virologia , Animais , COVID-19/imunologia , Quimioprevenção , Quirópteros/virologia , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Citidina/administração & dosagem , Citidina/uso terapêutico , Citocinas/imunologia , Células Epiteliais/virologia , Feminino , Xenoenxertos , Humanos , Imunidade Inata , Interferon Tipo I/imunologia , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Transplante de Pulmão , Masculino , Camundongos , Profilaxia Pós-Exposição , Profilaxia Pré-Exposição , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Replicação Viral
13.
Nat Commun ; 11(1): 5545, 2020 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-33139718

RESUMO

During development, cells gain positional information through the interpretation of dynamic morphogen gradients. A proposed mechanism for interpreting opposing morphogen gradients is mutual inhibition of downstream transcription factors, but isolating the role of this specific motif within a natural network remains a challenge. Here, we engineer a synthetic morphogen-induced mutual inhibition circuit in E. coli populations and show that mutual inhibition alone is sufficient to produce stable domains of gene expression in response to dynamic morphogen gradients, provided the spatial average of the morphogens falls within the region of bistability at the single cell level. When we add sender devices, the resulting patterning circuit produces theoretically predicted self-organised gene expression domains in response to a single gradient. We develop computational models of our synthetic circuits parameterised to timecourse fluorescence data, providing both a theoretical and experimental framework for engineering morphogen-induced spatial patterning in cell populations.


Assuntos
Escherichia coli/citologia , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/genética , Simulação por Computador , Regulação Bacteriana da Expressão Gênica , Redes Reguladoras de Genes , Modelos Biológicos , Biologia Sintética , Fatores de Transcrição
14.
Bull Math Biol ; 82(10): 136, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-33057872

RESUMO

Reaction-diffusion processes across layered media arise in several scientific domains such as pattern-forming E. coli on agar substrates, epidermal-mesenchymal coupling in development, and symmetry-breaking in cell polarization. We develop a modeling framework for bilayer reaction-diffusion systems and relate it to a range of existing models. We derive conditions for diffusion-driven instability of a spatially homogeneous equilibrium analogous to the classical conditions for a Turing instability in the simplest nontrivial setting where one domain has a standard reaction-diffusion system, and the other permits only diffusion. Due to the transverse coupling between these two regions, standard techniques for computing eigenfunctions of the Laplacian cannot be applied, and so we propose an alternative method to compute the dispersion relation directly. We compare instability conditions with full numerical simulations to demonstrate impacts of the geometry and coupling parameters on patterning, and explore various experimentally relevant asymptotic regimes. In the regime where the first domain is suitably thin, we recover a simple modulation of the standard Turing conditions, and find that often the broad impact of the diffusion-only domain is to reduce the ability of the system to form patterns. We also demonstrate complex impacts of this coupling on pattern formation. For instance, we exhibit non-monotonicity of pattern-forming instabilities with respect to geometric and coupling parameters, and highlight an instability from a nontrivial interaction between kinetics in one domain and diffusion in the other. These results are valuable for informing design choices in applications such as synthetic engineering of Turing patterns, but also for understanding the role of stratified media in modulating pattern-forming processes in developmental biology and beyond.


Assuntos
Modelos Biológicos , Animais , Biologia do Desenvolvimento , Difusão , Escherichia coli , Humanos , Cinética , Conceitos Matemáticos
15.
Res Sq ; 2020 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-32995766

RESUMO

All known recently emerged human coronaviruses likely originated in bats. Here, we used a single experimental platform based on human lung-only mice (LoM) to demonstrate efficient in vivo replication of all recently emerged human coronaviruses (SARS-CoV, MERS-CoV, SARS-CoV-2) and two highly relevant endogenous pre-pandemic SARS-like bat coronaviruses. Virus replication in this model occurs in bona fide human lung tissue and does not require any type of adaptation of the virus or the host. Our results indicate that bats harbor endogenous coronaviruses capable of direct transmission into humans. Further detailed analysis of pandemic SARS-CoV-2 in vivo infection of LoM human lung tissue showed predominant infection of human lung epithelial cells, including type II pneumocytes present in alveoli and ciliated airway cells. Acute SARS-CoV-2 infection was highly cytopathic and induced a robust and sustained Type I interferon and inflammatory cytokine/chemokine response. Finally, we evaluated a pre-exposure prophylaxis strategy for coronavirus infection. Our results show that prophylactic administration of EIDD-2801, an oral broad spectrum antiviral currently in phase II clinical trials for the treatment of COVID-19, dramatically prevented SARS-CoV-2 infection in vivo and thus has significant potential for the prevention and treatment of COVID-19.

17.
Front Psychiatry ; 11: 564, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32670106

RESUMO

Movement, behavioral, and neuropsychiatric disorders in children have been linked to infections and a group of anti-neuronal autoantibodies, implying dopamine receptor-mediated encephalitis within the basal ganglia. The purpose of this study was to determine if anti-neuronal biomarkers, when used as a group, confirmed the acute disease in Sydenham chorea (SC) and pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections (PANDAS). IgG autoantibodies against four neuronal autoantigens (tubulin, lysoganglioside GM1, and dopamine receptors D1 and D2) were detected in SC sera (N=8), sera and/or cerebrospinal fluid (CSF) from two groups of PANDAS cases (N=25 first group and N=35 second group), sera from Tourette's syndrome (N=18), obsessive-compulsive disorder (N=25), attention deficit hyperactivity disorder (N=18), and healthy controls (N=28) by direct enzyme-linked immunosorbent assay (ELISA). IgG specific for neuronal autoantigens was significantly elevated during the acute symptomatic phase, and the activity of calcium/calmodulin-dependent protein kinase II (CaMKII) pathway was significantly elevated in human neuronal cells. Five assays confirmed the disease in SC and in two groups of children with PANDAS. In 35 acute onset PANDAS patients, 32 sera (91.4%) were positive for one or more of the anti-neuronal autoantibodies compared with 9 of 28 healthy controls (32.1%, p<0.0001). Importantly, CSF of 32 (91.4%) PANDAS patients had one or more detectable anti-neuronal autoantibody titers and CaMKII activation. Among healthy control subjects with elevated serum autoantibody titers for individual antigens, none (0%) were positively associated with elevated positive CaMKII activation, which was a striking contrast to the sera of PANDAS subjects, who had 76-89% positive association with elevated individual autoantibody titers and positive CaMKII activity. At 6 months follow-up, symptoms improved for more than 80% of PANDAS subjects, and serum autoantibody titers also significantly decreased. Results reported herein and previously published studies in our laboratory suggest the antibody biomarkers may be a useful adjunct to clinical diagnosis of SC, PANDAS, and related disorders and are the first known group of autoantibodies detecting dopamine receptor-mediated encephalitis in children.

19.
Am J Med ; 133 Suppl 1: 1-27, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32362349

RESUMO

Hospitalized patients with acute medical illnesses are at risk for venous thromboembolism (VTE) during and after a hospital stay. Risk factors include physical immobilization and underlying pathophysiologic processes that activate the coagulation pathway and are still present after discharge. Strategies for optimal pharmacologic VTE thromboprophylaxis are evolving, and recommendations for VTE prophylaxis can be further refined to protect high-risk patients after hospital discharge. An early study of extended VTE prophylaxis with a parenteral agent in medically ill patients yielded inconclusive results with regard to efficacy and bleeding. In the Acute Medically Ill VTE Prevention with Extended Duration Betrixaban (APEX) trial, extended use of betrixaban halved symptomatic VTE, decreased hospital readmission, and reduced stroke and major adverse cardiovascular events compared with standard enoxaparin prophylaxis. Based on findings from APEX, the Food and Drug Administration approved betrixaban in 2017 for extended VTE prophylaxis in acute medically ill patients. In the Reducing Post-Discharge Venous Thrombo-Embolism Risk (MARINER) study, extended use of rivaroxaban halved symptomatic VTE in high-risk medical patients compared with placebo. In 2019, rivaroxaban was approved for extended thromboprophylaxis in high-risk medical patients, thus making available a new strategy for in-hospital and post-discharge VTE prevention. To address the critical unmet need for VTE prophylaxis in medically ill patients at the time of hospital discharge, the North American Thrombosis Forum (NATF) is launching the Anticoagulation Action Initiative, a comprehensive consensus document that provides practical guidance and straightforward, patient-centered recommendations for VTE prevention during hospitalization and after discharge.


Assuntos
Anticoagulantes/uso terapêutico , Tromboembolia Venosa/prevenção & controle , Adulto , Idoso , Benzamidas/uso terapêutico , Hospitalização , Humanos , Adesão à Medicação , Pessoa de Meia-Idade , Alta do Paciente , Guias de Prática Clínica como Assunto , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Piridonas/uso terapêutico , Medição de Risco , Fatores de Risco , Rivaroxabana/uso terapêutico , Tromboembolia Venosa/etiologia
20.
Lancet HIV ; 7(5): e340-e347, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32169158

RESUMO

BACKGROUND: The London patient (participant 36 in the IciStem cohort) underwent allogeneic stem-cell transplantation with cells that did not express CCR5 (CCR5Δ32/Δ32); remission was reported at 18 months after analytical treatment interruption (ATI). Here, we present longer term data for this patient (up to 30 months after ATI), including sampling from diverse HIV-1 reservoir sites. METHODS: We used ultrasensitive viral load assays of plasma, semen, and cerebrospinal fluid (CSF) samples to detect HIV-1 RNA. In gut biopsy samples and lymph-node tissue, cell-copy number and total HIV-1 DNA levels were quantified in multiple replicates, using droplet digital PCR (ddPCR) and quantitative real-time PCR. We also analysed the presence of intact proviral DNA using multiplex ddPCR targeting the packaging signal (ψ) and envelope (env). We did intracellular cytokine staining to measure HIV-1-specific T-cell responses. We used low-sensitive and low-avidity antibody assays to measure the humoral response to HIV-1. We predicted the probability of rebound using a mathematical model and inference approach. FINDINGS: HIV-1 viral load in plasma remained undetectable in the London patient up to 30 months (last tested on March 4, 2020), using an assay with a detection limit of 1 copy per mL. The patient's CD4 count was 430 cells per µL (23·5% of total T cells) at 28 months. A very low-level positive signal for HIV-1 DNA was recorded in peripheral CD4 memory cells at 28 months. The viral load in semen was undetectable in both plasma (lower limit of detection [LLD] <12 copies per mL) and cells (LLD 10 copies per 106 cells) at 21 months. CSF was within normal parameters at 25 months, with HIV-1 RNA below the detection limit (LLD 1 copy per mL). HIV-1 DNA by ddPCR was negative in rectum, caecum, and sigmoid colon and terminal ileum tissue samples at 22 months. Lymph-node tissue from axilla was positive for the long-terminal repeat (33 copies per 106 cells) and env (26·1 copies per 106 cells), negative for ψ and integrase, and negative by the intact proviral DNA assay, at 27 months. HIV-1-specific CD4 and CD8 T-cell responses have remained absent at 27 months. Low-avidity Env antibodies have continued to decline. Mathematical modelling suggests that the probability of remission for life (cure) is 98% in the context of 80% donor chimerism in total HIV target cells and greater than 99% probability of remission for life with 90% donor chimerism. INTERPRETATION: The London patient has been in HIV-1 remission for 30 months with no detectable replication-competent virus in blood, CSF, intestinal tissue, or lymphoid tissue. Donor chimerism has been maintained at 99% in peripheral T cells. We propose that these findings represent HIV-1 cure. FUNDING: Wellcome Trust and amfAR (American Foundation for AIDS Research).


Assuntos
Infecções por HIV/terapia , HIV-1 , Transplante de Células-Tronco Hematopoéticas , Receptores CCR5/metabolismo , Aloenxertos , Seguimentos , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Sêmen/virologia , Resultado do Tratamento , Carga Viral
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