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1.
Nature ; 619(7971): 811-818, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37407817

RESUMO

RNA viruses have evolved elaborate strategies to protect their genomes, including 5' capping. However, until now no RNA 5' cap has been identified for hepatitis C virus1,2 (HCV), which causes chronic infection, liver cirrhosis and cancer3. Here we demonstrate that the cellular metabolite flavin adenine dinucleotide (FAD) is used as a non-canonical initiating nucleotide by the viral RNA-dependent RNA polymerase, resulting in a 5'-FAD cap on the HCV RNA. The HCV FAD-capping frequency is around 75%, which is the highest observed for any RNA metabolite cap across all kingdoms of life4-8. FAD capping is conserved among HCV isolates for the replication-intermediate negative strand and partially for the positive strand. It is also observed in vivo on HCV RNA isolated from patient samples and from the liver and serum of a human liver chimeric mouse model. Furthermore, we show that 5'-FAD capping protects RNA from RIG-I mediated innate immune recognition but does not stabilize the HCV RNA. These results establish capping with cellular metabolites as a novel viral RNA-capping strategy, which could be used by other viruses and affect anti-viral treatment outcomes and persistence of infection.


Assuntos
Flavina-Adenina Dinucleotídeo , Hepacivirus , Capuzes de RNA , RNA Viral , Animais , Humanos , Camundongos , Quimera/virologia , Flavina-Adenina Dinucleotídeo/metabolismo , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/virologia , Reconhecimento da Imunidade Inata , Fígado/virologia , Estabilidade de RNA , RNA Viral/química , RNA Viral/genética , RNA Viral/imunologia , RNA Viral/metabolismo , RNA Polimerase Dependente de RNA/metabolismo , Replicação Viral/genética , Capuzes de RNA/metabolismo
2.
Nature ; 583(7814): 39-42, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32612222

RESUMO

The interiors of giant planets remain poorly understood. Even for the planets in the Solar System, difficulties in observation lead to large uncertainties in the properties of planetary cores. Exoplanets that have undergone rare evolutionary processes provide a route to understanding planetary interiors. Planets found in and near the typically barren hot-Neptune 'desert'1,2 (a region in mass-radius space that contains few planets) have proved to be particularly valuable in this regard. These planets include HD149026b3, which is thought to have an unusually massive core, and recent discoveries such as LTT9779b4 and NGTS-4b5, on which photoevaporation has removed a substantial part of their outer atmospheres. Here we report observations of the planet TOI-849b, which has a radius smaller than Neptune's but an anomalously large mass of [Formula: see text] Earth masses and a density of [Formula: see text] grams per cubic centimetre, similar to Earth's. Interior-structure models suggest that any gaseous envelope of pure hydrogen and helium consists of no more than [Formula: see text] per cent of the total planetary mass. The planet could have been a gas giant before undergoing extreme mass loss via thermal self-disruption or giant planet collisions, or it could have avoided substantial gas accretion, perhaps through gap opening or late formation6. Although photoevaporation rates cannot account for the mass loss required to reduce a Jupiter-like gas giant, they can remove a small (a few Earth masses) hydrogen and helium envelope on timescales of several billion years, implying that any remaining atmosphere on TOI-849b is likely to be enriched by water or other volatiles from the planetary interior. We conclude that TOI-849b is the remnant core of a giant planet.

3.
N Engl J Med ; 387(26): 2425-2435, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-36286254

RESUMO

BACKGROUND: Haloperidol is frequently used to treat delirium in patients in the intensive care unit (ICU), but evidence of its effect is limited. METHODS: In this multicenter, blinded, placebo-controlled trial, we randomly assigned adult patients with delirium who had been admitted to the ICU for an acute condition to receive intravenous haloperidol (2.5 mg 3 times daily plus 2.5 mg as needed up to a total maximum daily dose of 20 mg) or placebo. Haloperidol or placebo was administered in the ICU for as long as delirium continued and as needed for recurrences. The primary outcome was the number of days alive and out of the hospital at 90 days after randomization. RESULTS: A total of 1000 patients underwent randomization; 510 were assigned to the haloperidol group and 490 to the placebo group. Among these patients, 987 (98.7%) were included in the final analyses (501 in the haloperidol group and 486 in the placebo group). Primary outcome data were available for 963 patients (97.6%). At 90 days, the mean number of days alive and out of the hospital was 35.8 (95% confidence interval [CI], 32.9 to 38.6) in the haloperidol group and 32.9 (95% CI, 29.9 to 35.8) in the placebo group, with an adjusted mean difference of 2.9 days (95% CI, -1.2 to 7.0) (P = 0.22). Mortality at 90 days was 36.3% in the haloperidol group and 43.3% in the placebo group (adjusted absolute difference, -6.9 percentage points [95% CI, -13.0 to -0.6]). Serious adverse reactions occurred in 11 patients in the haloperidol group and in 9 patients in the placebo group. CONCLUSIONS: Among patients in the ICU with delirium, treatment with haloperidol did not lead to a significantly greater number of days alive and out of the hospital at 90 days than placebo. (Funded by Innovation Fund Denmark and others; AID-ICU ClinicalTrials.gov number, NCT03392376; EudraCT number, 2017-003829-15.).


Assuntos
Antipsicóticos , Delírio , Haloperidol , Adulto , Humanos , Antipsicóticos/efeitos adversos , Antipsicóticos/uso terapêutico , Cuidados Críticos , Delírio/tratamento farmacológico , Delírio/etiologia , Método Duplo-Cego , Haloperidol/efeitos adversos , Haloperidol/uso terapêutico , Unidades de Terapia Intensiva , Administração Intravenosa
4.
J Virol ; 97(4): e0181222, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-36971565

RESUMO

The lack of robust immunocompetent animal models for hepatitis C virus (HCV) impedes vaccine development and studies of immune responses. Norway rat hepacivirus (NrHV) infection in rats shares HCV-defining characteristics, including hepatotropism, chronicity, immune responses, and aspects of liver pathology. To exploit genetic variants and research tools, we previously adapted NrHV to prolonged infection in laboratory mice. Through intrahepatic RNA inoculation of molecular clones of the identified variants, we here characterized four mutations in the envelope proteins responsible for mouse adaptation, including one disrupting a glycosylation site. These mutations led to high-titer viremia, similar to that observed in rats. In 4-week-old mice, infection was cleared after around 5 weeks compared to 2 to 3 weeks for nonadapted virus. In contrast, the mutations led to persistent but attenuated infection in rats, and they partially reverted, accompanied by an increase in viremia. Attenuated infection in rat but not mouse hepatoma cells demonstrated that the characterized mutations were indeed mouse adaptive rather than generally adaptive across species and that species determinants and not immune interactions were responsible for attenuation in rats. Unlike persistent NrHV infection in rats, acute resolving infection in mice was not associated with the development of neutralizing antibodies. Finally, infection of scavenger receptor B-I (SR-BI) knockout mice suggested that adaptation to mouse SR-BI was not a primary function of the identified mutations. Rather, the virus may have adapted to lower dependency on SR-BI, thereby potentially surpassing species-specific differences. In conclusion, we identified specific determinants of NrHV mouse adaptation, suggesting species-specific interactions during entry. IMPORTANCE A prophylactic vaccine is required to achieve the World Health Organization's objective for hepatitis C virus elimination as a serious public health threat. However, the lack of robust immunocompetent animal models supporting hepatitis C virus infection impedes vaccine development as well as studies of immune responses and viral evasion. Hepatitis C virus-related hepaciviruses were discovered in a number of animal species and provide useful surrogate infection models. Norway rat hepacivirus is of particular interest, as it enables studies in rats, an immunocompetent and widely used small laboratory animal model. Its adaptation to robust infection also in laboratory mice provides access to a broader set of mouse genetic lines and comprehensive research tools. The presented mouse-adapted infectious clones will be of utility for reverse genetic studies, and the Norway rat hepacivirus mouse model will facilitate studies of hepacivirus infection for in-depth characterization of virus-host interactions, immune responses, and liver pathology.


Assuntos
Adaptação Fisiológica , Hepacivirus , Hepatite C , Adaptação Fisiológica/genética , Adaptação Fisiológica/imunologia , Hepacivirus/genética , Hepacivirus/imunologia , Viremia/imunologia , Viremia/virologia , Mutação , Animais , Camundongos , Ratos , Hepatite C/imunologia , Hepatite C/fisiopatologia , Hepatite C/virologia , Modelos Animais de Doenças , Hospedeiro Imunocomprometido , Linhagem Celular , Antígenos CD36/genética , Antígenos CD36/imunologia
5.
Acta Oncol ; 63: 56-61, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38404218

RESUMO

BACKGROUND AND PURPOSE: Proton therapy for breast cancer is usually given in free breathing (FB). With the use of deep inspiration breath-hold (DIBH) technique, the location of the heart is displaced inferiorly, away from the internal mammary nodes and, thus, the dose to the heart can potentially be reduced. The aim of this study was to explore the potential benefit of proton therapy in DIBH compared to FB for highly selected patients to reduce exposure of the heart and other organs at risk. We aimed at creating proton plans with delivery times feasible with treatment in DIBH. MATERIAL AND METHODS: Sixteen patients with left-sided breast cancer receiving loco-regional proton therapy were included. The FB and DIBH plans were created for each patient using spot-scanning proton therapy with 2-3 fields, robust and single field optimization. For the DIBH plans, minimum monitor unit per spot and spot spacing were increased to reduce treatment delivery time. RESULTS: All plans complied with target coverage constraints. The median mean heart dose was statistically significant reduced from 1.1 to 0.6 Gy relative biological effectiveness (RBE) by applying DIBH. No statistical significant difference was seen for mean dose and V17Gy RBE to the ipsilateral lung. The median treatment delivery time for the DIBH plans was reduced by 27% compared to the FB plans without compromising the plan quality. INTERPRETATION: The median absolute reduction in dose to the heart was limited. Proton treatment in DIBH may only be relevant for a subset of these patients with the largest reduction in heart exposure.


Assuntos
Neoplasias da Mama , Terapia com Prótons , Lesões por Radiação , Neoplasias Unilaterais da Mama , Humanos , Feminino , Neoplasias da Mama/radioterapia , Prótons , Dosagem Radioterapêutica , Suspensão da Respiração , Planejamento da Radioterapia Assistida por Computador/métodos , Coração , Neoplasias Unilaterais da Mama/radioterapia , Órgãos em Risco
6.
Nature ; 614(7949): 632-633, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36792896
7.
Acta Anaesthesiol Scand ; 68(1): 130-136, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37691474

RESUMO

BACKGROUND: Fluid overload is associated with increased mortality in intensive care unit (ICU) patients. The GODIF trial aims to assess the benefits and harms of fluid removal with furosemide versus placebo in stable adult patients with moderate to severe fluid overload in the ICU. This article describes the detailed statistical analysis plan for the primary results of the second version of the GODIF trial. METHODS: The GODIF trial is an international, multi-centre, randomised, stratified, blinded, parallel-group, pragmatic clinical trial, allocating 1000 adult ICU patients with moderate to severe fluid overload 1:1 to furosemide versus placebo. The primary outcome is days alive and out of hospital within 90 days post-randomisation. With a power of 90% and an alpha level of 5%, we may reject or detect an improvement of 8%. The primary analyses of all outcomes will be performed in the intention-to-treat population. For the primary outcome, the Kryger Jensen and Lange method will be used to compare the two treatment groups adjusted for stratification variables supplemented with sensitivity analyses in the per-protocol population and with further adjustments for prognostic variables. Secondary outcomes will be analysed with multiple linear regressions, logistic regressions or the Kryger Jensen and Lange method as suitable with adjustment for stratification variables. CONCLUSION: The GODIF trial data will increase the certainty about the effects of fluid removal using furosemide in adult ICU patients with fluid overload. TRIAL REGISTRATIONS: EudraCT identifier: 2019-004292-40 and ClinicalTrials.org: NCT04180397.


Assuntos
Furosemida , Desequilíbrio Hidroeletrolítico , Adulto , Humanos , Furosemida/uso terapêutico , Cuidados Críticos/métodos , Unidades de Terapia Intensiva , Resultado do Tratamento
8.
Hepatology ; 76(5): 1506-1519, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35445423

RESUMO

BACKGROUND AND AIMS: Lack of tractable immunocompetent animal models amenable to robust experimental challenge impedes vaccine efforts for HCV. Infection with rodent hepacivirus from Rattus norvegicus (RHV-rn1) in rats shares HCV-defining characteristics, including liver tropism, chronicity, and pathology. RHV in vitro cultivation would facilitate genetic studies on particle production, host factor interactions, and evaluation of antibody neutralization guiding HCV vaccine approaches. APPROACH AND RESULTS: We report an infectious reverse genetic cell culture system for RHV-rn1 using highly permissive rat hepatoma cells and adaptive mutations in the E2, NS4B, and NS5A viral proteins. Cell culture-derived RHV-rn1 particles (RHVcc) share hallmark biophysical characteristics of HCV and are infectious in mice and rats. Culture adaptive mutations attenuated RHVcc in immunocompetent rats, and the mutations reverted following prolonged infection, but not in severe combined immunodeficiency (SCID) mice, suggesting that adaptive immune pressure is a primary driver of reversion. Accordingly, sera from RHVcc-infected SCID mice or the early acute phase of immunocompetent mice and rats were infectious in culture. We further established an in vitro RHVcc neutralization assay, and observed neutralizing activity of rat sera specifically from the chronic phase of infection. Finally, we found that scavenger receptor class B type I promoted RHV-rn1 entry in vitro and in vivo. CONCLUSIONS: The RHV-rn1 infectious cell culture system enables studies of humoral immune responses against hepacivirus infection. Moreover, recapitulation of the entire RHV-rn1 infectious cycle in cell culture will facilitate reverse genetic studies and the exploration of tropism and virus-host interactions.


Assuntos
Hepacivirus , Hepatite C , Ratos , Camundongos , Animais , Hepacivirus/genética , Replicação Viral/genética , Anticorpos Anti-Hepatite C , Camundongos SCID , Proteínas Virais
9.
Scand J Med Sci Sports ; 33(12): 2585-2597, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37621063

RESUMO

BACKGROUND: Muscle strain injuries in the human calf muscles are frequent sports injuries with high recurrence. Potential structural and functional changes in the medial head of the musculus gastrocnemius (GM) and the associated aponeurosis are not well documented. PURPOSE: To test whether a GM muscle strain injury affects muscle fascicle length, pennation angle, and the morphology of the deep aponeurosis at rest and during muscle contraction long time after the injury. Additionally, electromyography (EMG) of the GM and the soleus muscle during a unilateral heel rise was measured in the injured and uninjured calf. METHODS: GM fascicle length, pennation angle, and aponeurosis thickness was analyzed on dynamic ultrasonography (US) recordings in 10 participants with a chronic calf strain. In addition, US images taken across the distal portion and mid-belly of the GM were analyzed at three different ankle positions. EMG recordings were obtained during a unilateral heel rise. RESULTS: The pennation angle of the injured distal GM was significantly larger compared to the uninjured GM in the contracted, but not the relaxed state. Pennation angle increased more in the injured compared to the uninjured GM during contraction. Fascicle length was shorter in the most distal portion of the injured GM. Fascicles at the distal portion of the injured GM showed a pronounced curvilinear shape as the muscle contracted and the aponeurosis was enlarged in the injured compared to the uninjured GM. The ratio between GM and soleus EMG activity showed a significantly higher relative soleus activity in the injured compared to the healthy calf. CONCLUSION: The greater change in pennation angle and curvilinear fascicle shape during contraction suggest that a long-term consequence after a muscle strain injury is that some muscle fibers at the distal GM are not actively engaged. The significantly enlarged aponeurosis indicates a substantial and long-lasting connective tissue involvement following strain injuries.


Assuntos
Aponeurose , Entorses e Distensões , Humanos , Aponeurose/diagnóstico por imagem , Músculo Esquelético/fisiologia , Eletromiografia , Fibras Musculares Esqueléticas , Contração Muscular/fisiologia , Ultrassonografia , Entorses e Distensões/diagnóstico por imagem
10.
Aging Ment Health ; 27(2): 343-349, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35232308

RESUMO

ObjectivesTo explore carers' experiences of everyday life impacted by people with dementia who attended a seven-week cognitive stimulation therapy (CST) group intervention.MethodsA systematic review of qualitative studies and qualitative mixed method studies was conducted. Eight databases were searched. The selected studies were screened and assessed for methodological quality using the Rayyan Qatar Computing Research Institute (QCRI) and Critical Appraisal Skills Programme Qualitative Checklist (CASP-QC). Three studies were included following an inductive content analysis.ResultsTwo themes were identified: 'Enrichment by enhanced communication' and 'Growth through positive emotional interaction'.ConclusionQualitative research on the impact of the CST group intervention on carers' everyday life with a person with dementia is scarce. Carers experienced feelings of enrichment due to improvement and equality in communication and a possible source of happiness. There was a sense of togetherness and reconnection through music and singing together as well as a sense of mutual growth, increased positive interaction, increased ability to socialize, and feelings of fondness when experiencing glimpses of the previous personality of the person with dementia. Nevertheless, knowledge about the impact of the CST group intervention on carers' personal everyday life is lacking and requires further research.


Assuntos
Cuidadores , Demência , Humanos , Cuidadores/psicologia , Demência/terapia , Demência/psicologia , Qualidade de Vida , Emoções , Cognição
11.
PLoS Pathog ; 16(7): e1008677, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32649726

RESUMO

Pegiviruses frequently cause persistent infection (as defined by >6 months), but unlike most other Flaviviridae members, no apparent clinical disease. Human pegivirus (HPgV, previously GBV-C) is detectable in 1-4% of healthy individuals and another 5-13% are seropositive. Some evidence for infection of bone marrow and spleen exists. Equine pegivirus 1 (EPgV-1) is not linked to disease, whereas another pegivirus, Theiler's disease-associated virus (TDAV), was identified in an outbreak of acute serum hepatitis (Theiler's disease) in horses. Although no subsequent reports link TDAV to disease, any association with hepatitis has not been formally examined. Here, we characterized EPgV-1 and TDAV tropism, sequence diversity, persistence and association with liver disease in horses. Among more than 20 tissue types, we consistently detected high viral loads only in serum, bone marrow and spleen, and viral RNA replication was consistently identified in bone marrow. PBMCs and lymph nodes, but not liver, were sporadically positive. To exclude potential effects of co-infecting agents in experimental infections, we constructed full-length consensus cDNA clones; this was enabled by determination of the complete viral genomes, including a novel TDAV 3' terminus. Clone derived RNA transcripts were used for direct intrasplenic inoculation of healthy horses. This led to productive infection detectable from week 2-3 and persisting beyond the 28 weeks of study. We did not observe any clinical signs of illness or elevation of circulating liver enzymes. The polyprotein consensus sequences did not change, suggesting that both clones were fully functional. To our knowledge, this is the first successful extrahepatic viral RNA launch and the first robust reverse genetics system for a pegivirus. In conclusion, equine pegiviruses are bone marrow tropic, cause persistent infection in horses, and are not associated with hepatitis. Based on these findings, it may be appropriate to rename the group of TDAV and related viruses as EPgV-2.


Assuntos
Medula Óssea/virologia , Infecções por Flavivirus/veterinária , Hepatite Viral Animal/virologia , Doenças dos Cavalos/virologia , Animais , Flaviviridae , Infecções por Flavivirus/virologia , Cavalos
12.
Hepatology ; 74(3): 1148-1163, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33713356

RESUMO

BACKGROUND AND AIMS: Equine hepacivirus (EqHV) is phylogenetically the closest relative of HCV and shares genome organization, hepatotropism, transient or persistent infection outcome, and the ability to cause hepatitis. Thus, EqHV studies are important to understand equine liver disease and further as an outbred surrogate animal model for HCV pathogenesis and protective immune responses. Here, we aimed to characterize the course of EqHV infection and associated protective immune responses. APPROACH AND RESULTS: Seven horses were experimentally inoculated with EqHV, monitored for 6 months, and rechallenged with the same and, subsequently, a heterologous EqHV. Clearance was the primary outcome (6 of 7) and was associated with subclinical hepatitis characterized by lymphocytic infiltrate and individual hepatocyte necrosis. Seroconversion was delayed and antibody titers waned slowly. Clearance of primary infection conferred nonsterilizing immunity, resulting in shortened duration of viremia after rechallenge. Peripheral blood mononuclear cell responses in horses were minimal, although EqHV-specific T cells were identified. Additionally, an interferon-stimulated gene signature was detected in the liver during EqHV infection, similar to acute HCV in humans. EqHV, as HCV, is stimulated by direct binding of the liver-specific microRNA (miR), miR-122. Interestingly, we found that EqHV infection sequesters enough miR-122 to functionally affect gene regulation in the liver. This RNA-based mechanism thus could have consequences for pathology. CONCLUSIONS: EqHV infection in horses typically has an acute resolving course, and the protective immune response lasts for at least a year and broadly attenuates subsequent infections. This could have important implications to achieve the primary goal of an HCV vaccine; to prevent chronicity while accepting acute resolving infection after virus exposure.


Assuntos
Regulação da Expressão Gênica , Hepacivirus/imunologia , Hepatite Viral Animal/imunologia , Fígado/imunologia , MicroRNAs/imunologia , Linfócitos T/imunologia , Animais , Progressão da Doença , Hepacivirus/metabolismo , Hepatite Viral Animal/genética , Cavalos , Fígado/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Transcriptoma
13.
Acta Anaesthesiol Scand ; 66(7): 898-903, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35580239

RESUMO

BACKGROUND: Delirium is highly prevalent in the intensive care unit (ICU) and is associated with high morbidity and mortality. The antipsychotic haloperidol is the most frequently used agent to treat delirium although this is not supported by solid evidence. The agents intervening against delirium in the intensive care unit (AID-ICU) trial investigates the effects of haloperidol versus placebo for the treatment of delirium in adult ICU patients. METHODS: This protocol describes the secondary, pre-planned Bayesian analyses of the primary and secondary outcomes up to day 90 of the AID-ICU trial. We will use Bayesian linear regression models for all count outcomes and Bayesian logistic regression models for all dichotomous outcomes. We will adjust for stratification variables (site and delirium subtype) and use weakly informative priors supplemented with sensitivity analyses using sceptical priors. We will present results as absolute differences (mean differences and risk differences) and relative differences (ratios of means and relative risks). Posteriors will be summarised using median values as point estimates and percentile-based 95% credibility intervals. Probabilities of any benefit/harm, clinically important benefit/harm and clinically unimportant differences will be presented for all outcomes. DISCUSSION: The results of this secondary, pre-planned Bayesian analysis will complement the primary frequentist analysis of the AID-ICU trial and facilitate a nuanced and probabilistic interpretation of the trial results.


Assuntos
Antipsicóticos , Delírio , Adulto , Antipsicóticos/uso terapêutico , Teorema de Bayes , Delírio/tratamento farmacológico , Haloperidol/uso terapêutico , Humanos , Unidades de Terapia Intensiva
14.
Nucleic Acids Res ; 48(10): 5555-5571, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32374844

RESUMO

Host microRNA (miRNA) dependency is a hallmark of the human pathogen hepatitis C virus (HCV) and was also described for the related pestiviruses, which are important livestock pathogens. The liver-specific miR-122 binds within the HCV 5' untranslated region (UTR), whereas the broadly expressed let-7 and miR-17 families bind two sites (S1 and S2, respectively) in the pestiviral 3' UTR. Here, we dissected the mechanism of miRNA dependency of the pestivirus bovine viral diarrhea virus (BVDV). Argonaute 2 (AGO2) and miR-17 binding were essential for viral replication, whereas let-7 binding was mainly required for full translational efficiency. Furthermore, using seed site randomized genomes and evolutionary selection experiments, we found that tropism could be redirected to different miRNAs. AGO cross-linking and immunoprecipitation (CLIP) experiments and miRNA antagonism demonstrated that these alternative variants bound and depended on the corresponding miRNAs. Interestingly, we also identified miRNA-independent variants that were obtained through acquisition of compensatory mutations near the genomic 3' terminus. Rescue experiments demonstrated that miRNA binding and 3' mutagenesis contribute to replication through mutually exclusive mechanisms. Altogether, our findings suggest that pestiviruses, although capable of miRNA-independent replication, took advantage of miRNAs as essential host factors, suggesting a favorable path during evolutionary adaptation.


Assuntos
Vírus da Diarreia Viral Bovina Tipo 1/genética , MicroRNAs/metabolismo , Regiões 3' não Traduzidas , Animais , Proteínas Argonautas/fisiologia , Vírus da Diarreia Viral Bovina Tipo 1/metabolismo , Vírus da Diarreia Viral Bovina Tipo 1/fisiologia , Cães , Evolução Molecular , Variação Genética , Células Madin Darby de Rim Canino , Biossíntese de Proteínas , Replicação Viral
15.
J Virol ; 93(19)2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31292246

RESUMO

Animal hepaciviruses represent promising surrogate models for hepatitis C virus (HCV), for which there are no efficient immunocompetent animal models. Experimental infection of laboratory rats with rodent hepacivirus isolated from feral Rattus norvegicus (RHV-rn1) mirrors key aspects of HCV infection in humans, including chronicity, hepatitis, and steatosis. Moreover, RHV has been adapted to infect immunocompetent laboratory mice. RHV in vitro systems have not been developed but would enable detailed studies of the virus life cycle crucial for designing animal experiments to model HCV infection. Here, we established efficient RHV-rn1 selectable subgenomic replicons with and without reporter genes. Rat and mouse liver-derived cells did not readily support the complete RHV life cycle, but replicon-containing cell clones could be selected with and without acquired mutations. Replication was significantly enhanced by mutations in NS4B and NS5A and in cell clones cured of replicon RNA. These mutations increased RHV replication of both mono- and bicistronic constructs, and CpG/UpA-dinucleotide optimization of reporter genes allowed replication. Using the replicon system, we show that the RHV-rn1 NS3-4A protease cleaves a human mitochondrial antiviral signaling protein reporter, providing a sensitive readout for virus replication. RHV-rn1 replication was inhibited by the HCV polymerase inhibitor sofosbuvir and high concentrations of HCV NS5A antivirals but not by NS3 protease inhibitors. The microRNA-122 antagonist miravirsen inhibited RHV-rn1 replication, demonstrating the importance of this HCV host factor for RHV. These novel RHV in vitro systems will be useful for studies of tropism, molecular virology, and characterization of virus-host interactions, thereby providing important complements to in vivo systems.IMPORTANCE A vaccine against hepatitis C virus (HCV) is crucial for global control of this important pathogen, which induces fatal human liver diseases. Vaccine development has been hampered by the lack of immunocompetent animal models. Discovery of rodent hepacivirus (RHV) enabled establishment of novel surrogate animal models. These allow robust infection and reverse genetic and immunization studies of laboratory animals, which develop HCV-like chronicity. Currently, there are no RHV in vitro systems available to study tropism and molecular virology. Here, we established the first culture systems for RHV, recapitulating the intracellular phase of the virus life cycle in vitro These replicon systems enabled identification of replication-enhancing mutations and selection of cells highly permissive to RHV replication, which allow study of virus-host interactions. HCV antivirals targeting NS5A, NS5B, and microRNA-122 efficiently inhibited RHV replication. Hence, several important aspects of HCV replication are shared by the rodent virus system, reinforcing its utility as an HCV model.


Assuntos
Hepacivirus/crescimento & desenvolvimento , Hepatite C Crônica/virologia , Hepatócitos/virologia , Modelos Biológicos , Replicação Viral , Animais , Antivirais/farmacologia , Hepacivirus/genética , Camundongos , Proteínas Mutantes/genética , Mutação , Ratos , Sofosbuvir/farmacologia , Proteínas não Estruturais Virais/genética
16.
Acta Anaesthesiol Scand ; 64(9): 1357-1364, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32592589

RESUMO

BACKGROUND: The AID-ICU trial aims to assess the benefits and harms of haloperidol for the treatment of delirium in acutely admitted, adult intensive care unit (ICU) patients. This paper describes the detailed statistical analysis plan for the primary publication of results from the AID-ICU trial. METHODS: The AID-ICU trial is an investigator-initiated, pragmatic, international, multicentre, randomized, blinded, parallel-group trial allocating 1000 adult ICU patients with manifest delirium 1:1 to haloperidol or placebo. The primary outcome measure is days alive and out of hospital within 90 days post-randomization. Secondary outcome measures are days alive without delirium or coma, serious adverse reactions (SARs) to haloperidol, use of escape medicine, days alive without mechanical ventilation, and mortality, health-related quality-of-life measures and cognitive function 1-year post-randomization. Statistical analysis will be conducted in accordance with the current pre-specified statistical analysis plan. One formal interim analysis will be performed. The primary outcome will be adjusted for stratification variables (site and delirium motor subtype) and compared between treatment groups using a likelihood ratio test described by Jensen et al A secondary analysis will be conducted with additional adjustment of the primary outcome for prognostic variables at baseline. The primary conclusion of the trial will be based on the intention-to-treat analysis of the primary outcome adjusted for stratification variables. CONCLUSION: The AID-ICU trial will provide important, high-quality data on the benefits and harms of treatment with haloperidol in acutely admitted, adult patients with manifest delirium in the ICU.


Assuntos
Delírio , Unidades de Terapia Intensiva , Adulto , Coma , Delírio/tratamento farmacológico , Haloperidol/uso terapêutico , Humanos , Respiração Artificial
17.
BMC Geriatr ; 20(1): 217, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32571229

RESUMO

BACKGROUND: Readmission is a serious and adverse event for elderly patients. Despite efforts, predicting the risk of readmission remains imprecise. The objective of this study is to examine if performance-based tests of daily activities can identify elderly patients at risk of readmission within 26 weeks after discharge from a short-stay unit in the emergency department. METHODS: The current study is an observational study based on data from 144 elderly patients included in a previous non-randomised controlled trial. Before discharge, patients were assessed for limitations in performing daily activities using three performance-based tests with predetermined cut-off values: the Assessment of Motor and Process Skills, Timed Up and Go and the 30s-Chair Stand Test. Outcome was risk of readmission within 26 weeks after discharge. RESULTS: Limitations in performing daily activities were associated with risk of readmission as measured by the Assessment of Motor and Process Skills motor scale (Crude OR = 4.38 [1.36; 14.12]), (Adjusted OR = 4.17 [1.18; 14.75]) and the 30s-Chair Stand Test (Adjusted OR = 3.36 [1.42; 7.93]). No significant associations were found in regards to other measures. CONCLUSION: The Assessment of Motor and Process Skills motor scale and the age, gender and comorbidity adjusted 30s-Chair Stand Test can identify elderly patients at increased risk of readmission after discharge from the emergency department. The results were limited by one-third of the patients did not perform the Assessment of Motor and Process Skills and the association between 30s-Chair Stand Test and risk of readmission were only positive when adjusted for age, gender and comorbidity.


Assuntos
Alta do Paciente , Readmissão do Paciente , Idoso , Serviço Hospitalar de Emergência , Humanos , Modalidades de Fisioterapia , Fatores de Risco
18.
Acta Anaesthesiol Scand ; 63(10): 1426-1433, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31350916

RESUMO

BACKGROUND: Delirium among patients in the intensive care unit (ICU) is a common condition associated with increased morbidity and mortality. Haloperidol is the most frequently used pharmacologic intervention, but its use is not supported by firm evidence. Therefore, we are conducting Agents Intervening against Delirium in the Intensive Care Unit (AID-ICU) trial to assess the benefits and harms of haloperidol for the treatment of ICU-acquired delirium. METHODS: AID-ICU is an investigator-initiated, pragmatic, international, randomised, blinded, parallel-group, trial allocating adult ICU patients with manifest delirium 1:1 to haloperidol or placebo. Trial participants will receive intravenous 2.5 mg haloperidol three times daily or matching placebo (isotonic saline 0.9%) if they are delirious. If needed, a maximum of 20 mg/daily haloperidol/placebo is given. An escape protocol, not including haloperidol, is part of the trial protocol. The primary outcome is days alive out of the hospital within 90 days post-randomisation. Secondary outcomes are number of days without delirium or coma, serious adverse reactions to haloperidol, usage of escape medication, number of days alive without mechanical ventilation; mortality, health-related quality-of-life and cognitive function at 1-year follow-up. A sample size of 1000 patients is required to detect a 7-day improvement or worsening of the mean days alive out of the hospital, type 1 error risk of 5% and power 90%. PERSPECTIVE: The AID-ICU trial is based on gold standard methodology applied to a large sample of clinically representative patients and will provide pivotal high-quality data on the benefits and harms of haloperidol for the treatment ICU-acquired delirium.


Assuntos
Delírio/tratamento farmacológico , Haloperidol/uso terapêutico , Unidades de Terapia Intensiva , Ensaios Clínicos Pragmáticos como Assunto , Humanos
19.
BMC Nephrol ; 19(1): 155, 2018 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-29966512

RESUMO

BACKGROUND: Although fatigue is common in dialysis patients, polypharmacy is seldom listed among its causes. In this report, we describe a dialysis patient who developed severe fatigue due to pharmacological interaction between two commonly prescribed drugs, phosphate binders and levothyroxine. CASE PRESENTATION: A 65-year old woman, on dialysis for 17 years, complained of fatigue (weight 54 Kg, height 1.55 m, BMI: 23 Kg/m2; malnutrition inflammation index: 10; Charlson index 9). She had been treated with lithium for about 20 years. A heavy smoker, she was obese and diabetic when young, but stopped treatment after weight loss. She had undergone thyroidectomy for papillary carcinoma, left hemicolectomy for colon adenocarcinoma, left quadrantectomy followed by radiotherapy for ductal mammary adenocarcinoma, subtotal parathyroidectomy for tertiary hyperparathyroidism. At the time of this report, she was on thrice-weekly hemodiafiltration (Daugirdas 2 Kt/V: 1.6-1.8). Her recent treatment included spironolactone, amlodipine, perindopril, valproate, lamotrigine, levothyroxine, vitamin D, calcium carbonate, sodium polystyrene and sevelamer. After she questioned her doctor about whether her fatigue might be the result of a drug interaction, levothyroxine interference was identified (TSH, previously normal, increased to 13.07 mU/L, after increasing sevelamer dose, and normalized after change of drug schedule). LITERATURE REVIEW: only 5 relevant papers on levothyroxine and phosphate binders on dialysis were found on Pubmed and EMBASE (out of 351 titles retrieved). Information was therefore inferred from studies in normal volunteers or in other diseases. DISCUSSION AND CONCLUSIONS: Our case differs from other reports on lower TSH at diagnosis, underlining the need for awareness of the importance of early diagnosis. Integrating the scant literature on dialysis patients with data available in the general population, some working conclusions can be reached: while all phosphate binders potentially interfere with levothyroxine absorption, interference seems to be highest for sevelamer; interference is limited but not excluded by increasing the intervals between drugs; morning fast is usually indicated but, when clashing with the timing of other drugs, a bedtime dose and liquid preparations may be indicated. In the absence of an agreed control schedule, our case supports close monitoring of TSH (1-3 months if unstable, twice-yearly in stable patients).


Assuntos
Hipotireoidismo/induzido quimicamente , Hipotireoidismo/metabolismo , Fosfatos/metabolismo , Polimedicação , Diálise Renal/efeitos adversos , Tiroxina/metabolismo , Idoso , Interações Medicamentosas/fisiologia , Feminino , Humanos , Hipotireoidismo/diagnóstico , Diálise Renal/tendências , Tiroxina/efeitos adversos , Tiroxina/uso terapêutico
20.
BMC Health Serv Res ; 18(1): 588, 2018 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-30055597

RESUMO

BACKGROUND: Limitations in performing daily activities and a incoherent discharge are risk factors for readmission of elderly patients after discharge from the emergency department. This paper describes the development and design of a complex intervention whose aim was to reduce the risk of readmission of elderly patients discharged from the emergency department. METHODS: The intervention was described using the Intervention Mapping approach. In step 1, a needs assessment was conducted to analyse causes of readmission. In steps 2 and 3, expected improvements in terms of intervention outcomes, performance objectives and change objectives were specified and linked to selected theory- and evidence-based methods. In step 4, the specific intervention components were developed; and in step 5, an implementation plan was described. Finally, in step 6, a plan for evaluating the effectiveness of the intervention was described. The intervention was informed by input from a literature search, informal interviews and an expert steering group. RESULTS: A three-phased theory- and evidence-based intervention was developed. The intervention consisted of 1) assessment of performance of daily activities, 2) defining a rehabilitation plan and 3) a follow-up home visit the day after discharge with focus on enhancing the patients' performance of daily activities. CONCLUSION: The intervention mapping protocol was found to be a useful method to describe and systemize this theory- and evidence-based intervention.


Assuntos
Serviço Hospitalar de Emergência/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Atividades Cotidianas , Idoso , Protocolos Clínicos , Dinamarca , Feminino , Implementação de Plano de Saúde , Humanos , Masculino , Terapia Ocupacional/métodos , Alta do Paciente/estatística & dados numéricos , Projetos Piloto , Fatores de Risco
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