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1.
EMBO Rep ; 25(2): 902-926, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38177924

RESUMEN

Viruses interact with numerous host factors to facilitate viral replication and to dampen antiviral defense mechanisms. We currently have a limited mechanistic understanding of how SARS-CoV-2 binds host factors and the functional role of these interactions. Here, we uncover a novel interaction between the viral NSP3 protein and the fragile X mental retardation proteins (FMRPs: FMR1, FXR1-2). SARS-CoV-2 NSP3 mutant viruses preventing FMRP binding have attenuated replication in vitro and reduced levels of viral antigen in lungs during the early stages of infection. We show that a unique peptide motif in NSP3 binds directly to the two central KH domains of FMRPs and that this interaction is disrupted by the I304N mutation found in a patient with fragile X syndrome. NSP3 binding to FMRPs disrupts their interaction with the stress granule component UBAP2L through direct competition with a peptide motif in UBAP2L to prevent FMRP incorporation into stress granules. Collectively, our results provide novel insight into how SARS-CoV-2 hijacks host cell proteins and provides molecular insight into the possible underlying molecular defects in fragile X syndrome.


Asunto(s)
COVID-19 , Síndrome del Cromosoma X Frágil , Humanos , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/metabolismo , Péptidos/metabolismo , Proteínas de Unión al ARN/genética , SARS-CoV-2
2.
J Hepatol ; 78(3): 604-613, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36410555

RESUMEN

BACKGROUND & AIMS: The evidence for hepatobiliary tumour surveillance in patients with primary sclerosing cholangitis (PSC) is scarce. In this study, we aimed to prospectively evaluate cholangiocarcinoma (CCA) surveillance with yearly MRI with cholangiopancreatography (MRI/MRCP) in a nationwide cohort. METHODS: In total, 512 patients with PSC from 11 Swedish hospitals were recruited. The study protocol included yearly clinical follow-ups, liver function tests and contrast-enhanced MRI/MRCP and carbohydrate antigen (CA) 19-9. Patients with severe/progressive bile duct changes on MRI/MRCP were further investigated with endoscopic retrograde cholangiopancreatography. Patients were followed for 5 years or until a diagnosis of CCA, liver transplantation (LT) and/or death. Risk factors associated with CCA were analysed with Cox regression. RESULTS: Eleven patients (2%) were diagnosed with CCA, and two (0.5%) with high-grade bile duct dysplasia. Severe/progressive bile duct changes on MRI/MRCP were detected in 122 patients (24%), of whom 10% had an underlying malignancy. The primary indication for LT (n = 54) was biliary dysplasia in nine patients (17%) and end-stage liver disease in 45 patients (83%), of whom three patients (7%) had unexpected malignancy in the explants. The median survival for patients with CCA was 13 months (3-22 months). Time to diagnosis of high-grade dysplasia and/or hepatobiliary malignancy was significantly associated with severe/progressive bile duct changes on MRI/MRCP (hazard ratio 10.50; 95% CI 2.49-44.31) and increased levels of CA19-9 (hazard ratio 1.00; 95% CI 1.00-1.01). CONCLUSION: In an unselected cohort of patients with PSC, yearly CA19-9 and MRI/MRCP surveillance followed by ERCP was ineffective in detecting cancer early enough to support long-term survival. Given the low occurrence of CCA, studies on individualised strategies for follow-up and improved diagnostic methods for PSC-related CCA are warranted. IMPACT AND IMPLICATIONS: A prospective nationwide 5-year study was conducted to evaluate yearly cholangiocarcinoma surveillance using MRI and CA19-9 in patients with primary sclerosing cholangitis. Only 2% of the patients were diagnosed with cholangiocarcinoma during follow-up and their prognosis remained poor despite surveillance. This surveillance strategy failed to detect cancer early enough to support long-term survival. Therefore, individualised strategies and improved diagnostic methods will be required to improve the early detection of cholangiocarcinoma in patients with primary sclerosing cholangitis.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Colangitis Esclerosante , Humanos , Colangitis Esclerosante/diagnóstico , Antígeno CA-19-9 , Estudios Prospectivos , Neoplasias de los Conductos Biliares/patología , Colangiocarcinoma/patología , Conductos Biliares Intrahepáticos/patología
3.
Liver Int ; 43(1): 127-138, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35535655

RESUMEN

BACKGROUND & AIMS: Evidence for the benefit of scheduled imaging for early detection of hepatobiliary malignancies in primary sclerosing cholangitis (PSC) is limited. We aimed to compare different follow-up strategies in PSC with the hypothesis that regular imaging improves survival. METHODS: We collected retrospective data from 2975 PSC patients from 27 centres. Patients were followed from the start of scheduled imaging or in case of clinical follow-up from 1 January 2000, until death or last clinical follow-up alive. The primary endpoint was all-cause mortality. RESULTS: A broad variety of different follow-up strategies were reported. All except one centre used regular imaging, ultrasound (US) and/or magnetic resonance imaging (MRI). Two centres used scheduled endoscopic retrograde cholangiopancreatography (ERCP) in addition to imaging for surveillance purposes. The overall HR (CI95%) for death, adjusted for sex, age and start year of follow-up, was 0.61 (0.47-0.80) for scheduled imaging with and without ERCP; 0.64 (0.48-0.86) for US/MRI and 0.53 (0.37-0.75) for follow-up strategies including scheduled ERCP. The lower risk of death remained for scheduled imaging with and without ERCP after adjustment for cholangiocarcinoma (CCA) or high-grade dysplasia as a time-dependent covariate, HR 0.57 (0.44-0.75). Hepatobiliary malignancy was diagnosed in 175 (5.9%) of the patients at 7.9 years of follow-up. Asymptomatic patients (25%) with CCA had better survival if scheduled imaging had been performed. CONCLUSIONS: Follow-up strategies vary considerably across centres. Scheduled imaging was associated with improved survival. Multiple factors may contribute to this result including early tumour detection and increased endoscopic treatment of asymptomatic benign biliary strictures.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Colangitis Esclerosante , Humanos , Colangitis Esclerosante/complicaciones , Colangitis Esclerosante/diagnóstico por imagen , Estudios Retrospectivos , Estudios de Seguimiento , Colangiocarcinoma/diagnóstico , Colangiopancreatografia Retrógrada Endoscópica , Conductos Biliares Intrahepáticos/patología , Neoplasias de los Conductos Biliares/diagnóstico
4.
Scand J Gastroenterol ; 58(1): 70-75, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35993428

RESUMEN

OBJECTIVES: Primary biliary cholangitis (PBC) is an autoimmune liver disease that may progress into liver cirrhosis. Ursodeoxycholic acid (UDCA) is known to prevent or delay the disease progression, but little is known about work incapacity in PBC patients. We aimed to compare clinical outcomes (transplantation-free survival; cirrhosis development) and sick leave in patients with PBC with and without UDCA therapy. METHODS: The medical records of 526 patients with PBC diagnosed from 2004 to 2016 were reviewed retrospectively. Sick leave data retrieved from the Swedish Social Insurance Agency were analysed for a sub-cohort of patients and matched controls. Cox regression was used for analysis of clinical outcomes. Logistic and conditional logistic regressions were used for sick leave analysis. RESULTS: A total of 10.6% of patients died and 3.4% received liver transplantation over a median follow-up time of 5.7 years. UDCA-untreated patients (HR 3.62 (95%CI 2.02-6.49)) and UDCA non-responders (HR 3.78 (95% CI 1.87-7.66)) had higher mortality or transplantation rates than UDCA responders. Patients with PBC had higher odds of sick leave (OR 2.50; 95% CI 1.69-3.70) than matched controls. Untreated patients were more likely to be on sick leave (OR 3.22; 95% CI 1.12-9.25) two years after diagnosis than UDCA responders. CONCLUSION: Both untreated patients and UDCA non-responders had lower liver transplantation-free survival rates than UDCA responders. Patients with PBC were more likely to be on sick leave compared to matched controls from the general population.


Asunto(s)
Cirrosis Hepática Biliar , Ácido Ursodesoxicólico , Humanos , Ácido Ursodesoxicólico/uso terapéutico , Cirrosis Hepática Biliar/tratamiento farmacológico , Estudios Retrospectivos , Colagogos y Coleréticos/uso terapéutico , Ausencia por Enfermedad , Suecia , Resultado del Tratamiento
5.
Euro Surveill ; 28(13)2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36995373

RESUMEN

BackgroundThe current SARS-CoV-2 pandemic has highlighted a need for easy and safe blood sampling in combination with accurate serological methodology. Venipuncture for testing is usually performed by trained staff at healthcare centres. Long travel distances to healthcare centres in rural regions may introduce a bias of testing towards relatively large communities with closer access. Rural regions are therefore often not represented in population-based data.AimThe aim of this retrospective cohort study was to develop and implement a strategy for at-home testing in a rural region of Sweden during spring 2021, and to evaluate its role to provide equal health care for its inhabitants.MethodsWe developed a sensitive method to measure antibodies to the S-protein of SARS-CoV-2 and optimised this assay for clinical use together with a strategy of at-home capillary blood sampling.ResultsWe demonstrated that our ELISA gave comparable results after analysis of capillary blood or serum from SARS-CoV-2-experienced individuals. We demonstrated stability of the assay under conditions that reflected temperature and humidity during winter or summer. By assessment of capillary blood samples from 4,122 individuals, we could show both feasibility of the strategy and that implementation shifted the geographical spread of testing in favour of rural areas.ConclusionImplementation of at-home sampling enabled citizens living in remote rural areas access to centralised and sensitive laboratory antibody tests. The strategy for testing used here could therefore enable disease control authorities to get rapid access to information concerning immunity to infectious diseases, even across vast geographical distance.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiología , Estudios Retrospectivos , Suecia/epidemiología , Prueba de COVID-19 , Anticuerpos Antivirales
6.
Liver Int ; 41(4): 754-763, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33219609

RESUMEN

BACKGROUND & AIMS: Non-alcoholic fatty liver disease (NAFLD) has been associated with multiple metabolic abnormalities. By applying a non-targeted metabolomics approach, we aimed at investigating whether serum metabolite profile that associates with NAFLD would differ in its association with NAFLD-related metabolic risk factors. METHODS & RESULTS: A total of 233 subjects (mean ± SD: 48.3 ± 9.3 years old; BMI: 43.1 ± 5.4 kg/m2 ; 64 male) undergoing bariatric surgery were studied. Of these participants, 164 with liver histology could be classified as normal liver (n = 79), simple steatosis (SS, n = 40) or non-alcoholic steatohepatitis (NASH, n = 45). Among the identified fasting serum metabolites with higher levels in those with NASH when compared to those with normal phenotype were the aromatic amino acids (AAAs: tryptophan, tyrosine and phenylalanine), the branched-chain amino acids (BCAAs: leucine and isoleucine), a phosphatidylcholine (PC(16:0/16:1)) and uridine (all FDRp < 0.05). Only tryptophan was significantly higher in those with NASH compared to those with SS (FDRp < 0.05). Only the AAAs tryptophan and tyrosine correlated positively with serum total and LDL cholesterol (FDRp < 0.1), and accordingly, with liver LDLR at mRNA expression level. In addition, tryptophan was the single AA associated with liver DNA methylation of CpG sites known to be differentially methylated in those with NASH. CONCLUSIONS: We found that serum levels of the NASH-related AAAs and BCAAs demonstrate divergent associations with serum lipids. The specific correlation of tryptophan with LDL-c may result from the molecular events affecting LDLR mRNA expression and NASH-associated methylation of genes in the liver.


Asunto(s)
Cirugía Bariátrica , Enfermedad del Hígado Graso no Alcohólico , Adulto , Aminoácidos de Cadena Ramificada , Humanos , Masculino , Persona de Mediana Edad , Fosfatidilcolinas
7.
J Gastroenterol Hepatol ; 36(4): 936-942, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32790935

RESUMEN

BACKGROUND AND AIM: The prevalence and clinical significance of extrahepatic autoimmune diseases (EHAIDs) have not been evaluated in a large cohort of primary biliary cholangitis (PBC). METHODS: The medical records of 1554 patients with PBC from 20 international centers were retrospectively reviewed. Development of decompensated cirrhosis (ascites, variceal bleeding, and/or hepatic encephalopathy) and hepatocellular carcinoma were considered clinical endpoints. RESULTS: A total of 35 different EHAIDs were diagnosed in 440 (28.3%) patients with PBC. Patients with EHAIDs were more often female (92.5% vs 86.1%, P < 0.001) and seropositive for anti-mitochondrial antibodies (88% vs 84%, P = 0.05) and antinuclear antibodies and/or smooth muscle antibodies (53.8% vs 43.6%, P = 0.005). At presentation, patients with EHAIDs had significantly lower levels of alkaline phosphatase (1.76 vs 1.98 × upper limit of normal [ULN], P = 0.006), aspartate aminotransferase (1.29 vs 1.50 × ULN, P < 0.001), and total bilirubin (0.53 vs 0.58 × ULN, P = 0.002). Patients with EHAIDs and without EHAIDs had similar rates of GLOBE high-risk status (12.3% vs 16.1%, P = 0.07) and Paris II response (71.4% vs 69.4%, P = 0.59). Overall, event-free survival was not different in patients with and without EHAIDs (90.8% vs 90.7%, P = 0.53, log rank). Coexistence of each autoimmune thyroid diseases (10.6%), Sjögren disease (8.3%), systemic sclerosis (2.9%), rheumatoid arthritis (2.7%), systemic lupus erythematosus (1.7%), celiac disease (1.7%), psoriasis (1.5%), and inflammatory bowel diseases (1.3%) did not influence the outcome. CONCLUSIONS: Our study confirms that EHAIDs are frequently diagnosed in patients with PBC. The presence of EHAIDs may influence the clinical phenotype of PBC at presentation but has no impact on PBC outcome.


Asunto(s)
Enfermedades Autoinmunes/epidemiología , Enfermedades Autoinmunes/etiología , Cirrosis Hepática Biliar/complicaciones , Fosfatasa Alcalina/sangre , Anticuerpos Antinucleares/sangre , Aspartato Aminotransferasas/sangre , Autoanticuerpos/sangre , Enfermedades Autoinmunes/diagnóstico , Enfermedades Autoinmunes/inmunología , Bilirrubina/sangre , Biomarcadores/sangre , Femenino , Humanos , Cirrosis Hepática Biliar/diagnóstico , Masculino , Mitocondrias/inmunología , Prevalencia , Pronóstico , Factores Sexuales
8.
Mol Cell Proteomics ; 18(12): 2401-2417, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31570497

RESUMEN

Novel tick-borne phleboviruses in the Phenuiviridae family, which are highly pathogenic in humans and all closely related to Uukuniemi virus (UUKV), have recently emerged on different continents. How phleboviruses assemble, bud, and exit cells remains largely elusive. Here, we performed high-resolution, label-free mass spectrometry analysis of UUKV immunoprecipitated from cell lysates and identified 39 cellular partners interacting with the viral envelope glycoproteins. The importance of these host factors for UUKV infection was validated by silencing each host factor by RNA interference. This revealed Golgi-specific brefeldin A-resistance guanine nucleotide exchange factor 1 (GBF1), a guanine nucleotide exchange factor resident in the Golgi, as a critical host factor required for the UUKV life cycle. An inhibitor of GBF1, Golgicide A, confirmed the role of the cellular factor in UUKV infection. We could pinpoint the GBF1 requirement to UUKV replication and particle assembly. When the investigation was extended to viruses from various positive and negative RNA viral families, we found that not only phleboviruses rely on GBF1 for infection, but also Flavi-, Corona-, Rhabdo-, and Togaviridae In contrast, silencing or blocking GBF1 did not abrogate infection by the human adenovirus serotype 5 and immunodeficiency retrovirus type 1, the replication of both requires nuclear steps. Together our results indicate that UUKV relies on GBF1 for viral replication, assembly and egress. This study also highlights the proviral activity of GBF1 in the infection by a broad range of important zoonotic RNA viruses.


Asunto(s)
Factores de Intercambio de Guanina Nucleótido/metabolismo , Virus Uukuniemi/fisiología , Animales , Antivirales/farmacología , Infecciones por Bunyaviridae/virología , Línea Celular Tumoral , Chlorocebus aethiops , Glicoproteínas/metabolismo , Interacciones Microbiota-Huesped , Humanos , Espectrometría de Masas , Proteómica , Piridinas/farmacología , Quinolinas/farmacología , Interferencia de ARN , Virus ARN/fisiología , Virus Uukuniemi/efectos de los fármacos , Células Vero , Proteínas del Envoltorio Viral/metabolismo , Liberación del Virus , Replicación Viral
9.
Clin Gastroenterol Hepatol ; 18(10): 2295-2304.e2, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32068151

RESUMEN

BACKGROUND & AIMS: Few patients with primary sclerosing cholangitis (PSC) and inflammatory bowel diseases (IBDs) are exposed to tumor necrosis factor (TNF) antagonists because of the often mild symptoms of IBD. We assessed the effects of anti-TNF agents on liver function in patients with PSC and IBD, and their efficacy in treatment of IBD. METHODS: We performed a retrospective analysis of 141 patients with PSC and IBD receiving treatment with anti-TNF agents (infliximab or adalimumab) at 20 sites (mostly tertiary-care centers) in Europe and North America. We collected data on the serum level of alkaline phosphatase (ALP). IBD response was defined as either endoscopic response or, if no endoscopic data were available, clinical response, as determined by the treating clinician or measurements of fecal calprotectin. Remission was defined more stringently as endoscopic mucosal healing. We used linear regression analysis to identify factors associated significantly with level of ALP during anti-TNF therapy. RESULTS: Anti-TNF treatment produced a response of IBD in 48% of patients and remission of IBD in 23%. There was no difference in PSC symptom frequency before or after drug exposure. The most common reasons for anti-TNF discontinuation were primary nonresponse of IBD (17%) and side effects (18%). At 3 months, infliximab-treated patients had a median reduction in serum level of ALP of 4% (interquartile range, reduction of 25% to increase of 19%) compared with a median 15% reduction in ALP in adalimumab-treated patients (interquartile range, reduction of 29% to reduction of 4%; P = .035). Factors associated with lower ALP were normal ALP at baseline (P < .01), treatment with adalimumab (P = .090), and treatment in Europe (P = .083). CONCLUSIONS: In a retrospective analysis of 141 patients with PSC and IBD, anti-TNF agents were moderately effective and were not associated with exacerbation of PSC symptoms or specific side effects. Prospective studies are needed to investigate the association between use of adalimumab and reduced serum levels of ALP further.


Asunto(s)
Colangitis Esclerosante , Enfermedades Inflamatorias del Intestino , Adalimumab/efectos adversos , Colangitis Esclerosante/tratamiento farmacológico , Humanos , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Infliximab/efectos adversos , Estudios Retrospectivos , Inhibidores del Factor de Necrosis Tumoral , Factor de Necrosis Tumoral alfa
10.
J Sleep Res ; 29(5): e12962, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-31828862

RESUMEN

The effects of driver sleepiness are often quantified as deteriorated driving performance, increased blink durations and high levels of subjective sleepiness. Driver sleepiness has also been associated with increasing levels of electroencephalogram (EEG) power, especially in the alpha range. The present exploratory study investigated a new measure of driver sleepiness, the EEG fixation-related lambda response. Thirty young male drivers (23.6 ± 1.7 years old) participated in a driving simulator experiment in which they drove on rural and suburban roads in simulated daylight versus darkness during both the daytime (full sleep) and night-time (sleep deprived). The results show lower lambda responses during night driving and with longer time on task, indicating that sleep deprivation and time on task cause a general decrement in cortical responsiveness to incoming visual stimuli. Levels of subjective sleepiness and line crossings were higher under the same conditions. Furthermore, results of a linear mixed-effects model showed that low lambda responses are associated with high subjective sleepiness and more line crossings. We suggest that the fixation-related lambda response can be used to investigate driving impairment induced by sleep deprivation while driving and that, after further refinement, it may be useful as an objective measure of driver sleepiness.


Asunto(s)
Conducción de Automóvil/psicología , Encéfalo/fisiopatología , Electroencefalografía/métodos , Somnolencia , Adulto , Femenino , Humanos , Masculino , Adulto Joven
11.
Am J Gastroenterol ; 114(7): 1101-1108, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31241547

RESUMEN

INTRODUCTION: Risk stratification based on biochemical variables is a useful tool for monitoring ursodeoxycholic acid (UDCA)-treated patients with primary biliary cholangitis (PBC). Several UDCA response criteria and scoring systems have been proposed for risk prediction in PBC, but these have not been validated in large external cohorts. METHODS: We performed a study on data of 1746 UDCA-treated patients with PBC from 25 centers in Europe, United States, and Canada. The prognostic performance of the risk scoring systems (GLOBE and UK-PBC) and the UDCA response criteria (Barcelona, Paris I, Paris II, Rotterdam, and Toronto) were evaluated. We regarded cirrhosis-related complications (ascites, variceal bleeding, and/or hepatic encephalopathy) as clinical end points. RESULTS: A total of 171 patients reached a clinical end point during a median 7 years (range 1-16 years) of follow-up. The 5-, 10- and 15-year adverse outcome-free survivals were 95%, 85%, and 77%. The GLOBE and UK-PBC scores predicted cirrhosis-related complications better than the UDCA response criteria. The hazard ratio (HR) for a 1 standard deviation increase was HR 5.05 (95% confidence interval (CI): 4.43-5.74, P < 0.001) for the GLOBE score and HR 3.39 (95% CI: 3.10-3.72, P < 0.001) for the UK-PBC score. Overall, the GLOBE and UK-PBC risk scores showed similar and excellent prognostic performance (C-statistic, 0.93; 95% CI: 0.91%-95% vs 0.94; 95% CI: 0.91%-0.96%). DISCUSSION: In our international, multicenter PBC cohort, the GLOBE and UK-PBC risk scoring systems were good predictors of future cirrhosis-related complications.


Asunto(s)
Colagogos y Coleréticos/uso terapéutico , Progresión de la Enfermedad , Cirrosis Hepática Biliar/diagnóstico , Cirrosis Hepática Biliar/tratamiento farmacológico , Ácido Ursodesoxicólico/uso terapéutico , Adulto , Factores de Edad , Estudios de Cohortes , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Internacionalidad , Estimación de Kaplan-Meier , Cirrosis Hepática Biliar/mortalidad , Cirrosis Hepática Biliar/patología , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Factores Sexuales , Análisis de Supervivencia , Resultado del Tratamiento
12.
J Virol ; 92(1)2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29046456

RESUMEN

Efficient antiviral immunity requires interference with virus replication at multiple layers targeting diverse steps in the viral life cycle. We describe here a novel flavivirus inhibition mechanism that results in interferon-mediated obstruction of tick-borne encephalitis virus particle assembly and involves release of malfunctioning membrane-associated capsid (C) particles. This mechanism is controlled by the activity of the interferon-induced protein viperin, a broad-spectrum antiviral interferon-stimulated gene. Through analysis of the viperin-interactome, we identified the Golgi brefeldin A-resistant guanine nucleotide exchange factor 1 (GBF1) as the cellular protein targeted by viperin. Viperin-induced antiviral activity, as well as C-particle release, was stimulated by GBF1 inhibition and knockdown and reduced by elevated levels of GBF1. Our results suggest that viperin targets flavivirus virulence by inducing the secretion of unproductive noninfectious virus particles via a GBF1-dependent mechanism. This as-yet-undescribed antiviral mechanism allows potential therapeutic intervention.IMPORTANCE The interferon response can target viral infection on almost every level; however, very little is known about the interference of flavivirus assembly. We show here that interferon, through the action of viperin, can disturb the assembly of tick-borne encephalitis virus. The viperin protein is highly induced after viral infection and exhibit broad-spectrum antiviral activity. However, the mechanism of action is still elusive and appears to vary between the different viruses, indicating that cellular targets utilized by several viruses might be involved. In this study, we show that viperin induces capsid particle release by interacting and inhibiting the function of the cellular protein Golgi brefeldin A-resistant guanine nucleotide exchange factor 1 (GBF1). GBF1 is a key protein in the cellular secretory pathway and is essential in the life cycle of many viruses, also targeted by viperin, implicating GBF1 as a novel putative drug target.


Asunto(s)
Infecciones por Flavivirus/metabolismo , Factores de Intercambio de Guanina Nucleótido/metabolismo , Interferón Tipo I/farmacología , Proteínas/metabolismo , Células A549 , Animales , Proteínas de la Cápside/metabolismo , Chlorocebus aethiops , Flavivirus/efectos de los fármacos , Flavivirus/patogenicidad , Infecciones por Flavivirus/tratamiento farmacológico , Infecciones por Flavivirus/virología , Regulación de la Expresión Génica , Factores de Intercambio de Guanina Nucleótido/genética , Células HEK293 , Células HeLa , Humanos , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH , Células Vero , Virulencia , Ensamble de Virus/efectos de los fármacos
13.
Scand J Gastroenterol ; 54(8): 1027-1032, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31389730

RESUMEN

Background and aims: Liver cirrhosis is a risk factor for hepatocellular carcinoma (HCC). While the HCC risk is thought to be highest in hepatitis B and hepatitis C, the risk in other cirrhosis etiologies is not fully established. Therefore, we aimed to study the risk and outcome of HCC in alcoholic cirrhosis compared to cirrhosis of other etiologies, in Sweden. Material and methods: We used population-based medical registries to identify patients diagnosed with cirrhosis in the Scania region in southern Sweden between 2001 and 2010. Medical records were reviewed to identify all HCC cases and to register clinical parameters. All patients were followed until death, emigration or December 2017. Results: The cohort comprised 1317 patients with cirrhosis. A total of 200 patient developed HCC, including 75 with prevalent HCC. The annual incidence of HCC after six months was 1.5% in alcoholic cirrhosis and 4.7% in hepatitis C cirrhosis. In alcoholic cirrhosis, 40 patients were diagnosed with HCC during follow-up, of which 15 patients fulfilled the Milan criteria and 10 received treatment, curative or palliative. The overall median survival after HCC diagnosis was 7.7 months, with 4.5, 11 and 9.3 months, in cirrhosis due to alcohol, hepatitis C or remaining causes, respectively. Conclusion: We find an annual incidence of HCC in alcoholic cirrhosis of 1.5% indicating need for surveillance in these patients. Survival after HCC diagnosis was worst in alcoholic cirrhosis due to more advanced stage at diagnosis with few patients eligible for treatment.


Asunto(s)
Carcinoma Hepatocelular/etiología , Hepatitis C Crónica/complicaciones , Cirrosis Hepática Alcohólica/complicaciones , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/etiología , Carcinoma Hepatocelular/epidemiología , Carcinoma Hepatocelular/mortalidad , Estudios de Cohortes , Femenino , Humanos , Incidencia , Neoplasias Hepáticas/epidemiología , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Sistema de Registros , Factores de Riesgo , Análisis de Supervivencia , Suecia/epidemiología
14.
J Dairy Sci ; 102(6): 5458-5465, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30954264

RESUMEN

The importance of rest and sleep is well established; we know, for example, that lack of sleep impairs immune function in rats and increases pain sensitivity in humans. However, little is known about sleep in dairy cows, but a lack of rest and sleep is discussed as a possible welfare problem in cattle. A first step toward a better understanding of sleep in dairy cows is to quantify the time cows spend awake and asleep in different stages of lactation. Using electrophysiological recordings on 7 occasions in wk -2, 2, 7, 13, 22, 37, and 45 in relation to calving, we investigated changes in rapid eye movement (REM) sleep time as well as non-rapid eye movement (NREM) sleep, drowsing, awake, and rumination in 19 dairy cows of the Swedish Red breed kept in single pens with ad libitum access to feed and water. The recordings on wk -2 and 45 were conducted during the dry period, and all others during lactation. The PROC MIXED procedure in SAS (SAS Institute Inc., Cary, NC) was used to test for significant differences in REM, NREM, drowsing, awake, and rumination between the different stages of lactation cycle. Pairwise comparisons between all recording occasions showed that total REM sleep duration was shorter for cows in wk 2 relative to calving compared with wk -2, and the number of REM sleep bouts were fewer in wk 2 compared with wk -2. The REM sleep was recorded during both the day (0500-2100 h) and night (2100-0500 h), but predominantly performed at night compared with daytime, and the bout duration was longer during nighttime compared with daytime. A tendency was observed for time spent in NREM sleep to be shorter in wk 2 relative to calving compared with wk -2. The duration spent drowsing was shorter for cows in wk 2 and 13 relative to calving compared with wk -2. We found no effect of stage of lactation cycle on the duration of awake or ruminating. Our study is the first to assess sleep distribution during a lactation cycle, and our results show that stage of lactation is important to consider when moving forward with sleep investigations in dairy cows. The shortest REM sleep duration was found for cows 2 wk after calving and longest 2 wk before calving, and the difference was due a higher number of REM sleep bouts in the recording 2 wk before calving. The REM sleep and rumination predominantly occurred at night but were recorded during both day and night.


Asunto(s)
Bovinos/fisiología , Lactancia/fisiología , Sueño REM/fisiología , Animales , Femenino , Factores de Tiempo
15.
Scand J Gastroenterol ; 53(4): 475-481, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29513096

RESUMEN

OBJECTIVES: Liver cirrhosis is characterized by a silent phase until decompensation, which is defined by onset of ascites, variceal bleeding, or encephalopathy. Although it is presumed that the survival of decompensated patients is the same regardless of when decompensation occurs, data to support this are scarce. We aimed to study the impact of time of decompensation on the clinical course and survival of patients with cirrhosis in a large population-based cohort. MATERIALS AND METHODS: We used medical registries to define a 10-year cohort of 1317 patients with incident liver cirrhosis in the Scania region of Sweden. Medical records were reviewed. Patients were followed until December 2011, and for death or transplantation until December 2014. RESULTS: In the cohort, 629 patients were decompensated at diagnosis, of which 505 had ascites and 44 variceal bleeding only. During follow-up, 228 patients developed ascites and 39 variceal bleeding as first complication. Patients with ascites as first complication showed worse survival than patients who had ascites at diagnosis. (5-year survival 33% vs. 15%, HR 1.60 (95% CI 1.34-1.90)). This difference persisted after adjustment for confounders, including hepatocellular cancer (HR 1.38 (95% CI 1.15-1.67)). Worse survival was also seen when bleeding from varices occurred during follow-up rather than at diagnosis. CONCLUSIONS: Our results provide evidence for an association between transplantation-free survival after decompensation and the time of decompensation in liver cirrhosis, with worse survival when decompensation occurs during follow-up, thus challenging the generally held, view that the survival after decompensation is independent of when decompensation occurs.


Asunto(s)
Carcinoma Hepatocelular/mortalidad , Várices Esofágicas y Gástricas/complicaciones , Cirrosis Hepática/complicaciones , Cirrosis Hepática/mortalidad , Neoplasias Hepáticas/mortalidad , Ascitis/etiología , Estudios de Cohortes , Femenino , Hemorragia Gastrointestinal/etiología , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia , Suecia/epidemiología , Factores de Tiempo
16.
Hum Mol Genet ; 24(13): 3792-813, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25861810

RESUMEN

Increased age, BMI and HbA1c levels are risk factors for several non-communicable diseases. However, the impact of these factors on the genome-wide DNA methylation pattern in human adipose tissue remains unknown. We analyzed the DNA methylation of ∼480 000 sites in human adipose tissue from 96 males and 94 females and related methylation to age, BMI and HbA1c. We also compared epigenetic signatures in adipose tissue and blood. Age was significantly associated with both altered DNA methylation and expression of 1050 genes (e.g. FHL2, NOX4 and PLG). Interestingly, many reported epigenetic biomarkers of aging in blood, including ELOVL2, FHL2, KLF14 and GLRA1, also showed significant correlations between adipose tissue DNA methylation and age in our study. The most significant association between age and adipose tissue DNA methylation was found upstream of ELOVL2. We identified 2825 genes (e.g. FTO, ITIH5, CCL18, MTCH2, IRS1 and SPP1) where both DNA methylation and expression correlated with BMI. Methylation at previously reported HIF3A sites correlated significantly with BMI in females only. HbA1c (range 28-46 mmol/mol) correlated significantly with the methylation of 711 sites, annotated to, for example, RAB37, TICAM1 and HLA-DPB1. Pathway analyses demonstrated that methylation levels associated with age and BMI are overrepresented among genes involved in cancer, type 2 diabetes and cardiovascular disease. Our results highlight the impact of age, BMI and HbA1c on epigenetic variation of candidate genes for obesity, type 2 diabetes and cancer in human adipose tissue. Importantly, we demonstrate that epigenetic biomarkers in blood can mirror age-related epigenetic signatures in target tissues for metabolic diseases such as adipose tissue.


Asunto(s)
Tejido Adiposo/metabolismo , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/genética , Hemoglobina Glucada/metabolismo , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Estudios de Cohortes , Islas de CpG , Metilación de ADN , Dinamarca , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Persona de Mediana Edad , Suecia , Población Blanca/genética , Adulto Joven
17.
BMC Med ; 15(1): 39, 2017 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-28222718

RESUMEN

BACKGROUND: Human skeletal muscle stem cells are important for muscle regeneration. However, the combined genome-wide DNA methylation and expression changes taking place during adult myogenesis have not been described in detail and novel myogenic factors may be discovered. Additionally, obesity is associated with low relative muscle mass and diminished metabolism. Epigenetic alterations taking place during myogenesis might contribute to these defects. METHODS: We used Infinium HumanMethylation450 BeadChip Kit (Illumina) and HumanHT-12 Expression BeadChip (Illumina) to analyze genome-wide DNA methylation and transcription before versus after differentiation of primary human myoblasts from 14 non-obese and 14 obese individuals. Functional follow-up experiments were performed using siRNA mediated gene silencing in primary human myoblasts and a transgenic mouse model. RESULTS: We observed genome-wide changes in DNA methylation and expression patterns during differentiation of primary human muscle stem cells (myoblasts). We identified epigenetic and transcriptional changes of myogenic transcription factors (MYOD1, MYOG, MYF5, MYF6, PAX7, MEF2A, MEF2C, and MEF2D), cell cycle regulators, metabolic enzymes and genes previously not linked to myogenesis, including IL32, metallothioneins, and pregnancy-specific beta-1-glycoproteins. Functional studies demonstrated IL-32 as a novel target that regulates human myogenesis, insulin sensitivity and ATP levels in muscle cells. Furthermore, IL32 transgenic mice had reduced insulin response and muscle weight. Remarkably, approximately 3.7 times more methylation changes (147,161 versus 39,572) were observed during differentiation of myoblasts from obese versus non-obese subjects. In accordance, DNMT1 expression increased during myogenesis only in obese subjects. Interestingly, numerous genes implicated in metabolic diseases and epigenetic regulation showed differential methylation and expression during differentiation only in obese subjects. CONCLUSIONS: Our study identifies IL-32 as a novel myogenic regulator, provides a comprehensive map of the dynamic epigenome during differentiation of human muscle stem cells and reveals abnormal epigenetic changes in obesity.


Asunto(s)
Músculo Esquelético/fisiología , Obesidad/genética , Obesidad/patología , Células Madre/fisiología , Animales , Diferenciación Celular/genética , Metilación de ADN , Epigénesis Genética , Humanos , Ratones , Persona de Mediana Edad , Desarrollo de Músculos , Músculo Esquelético/patología , Células Madre/patología
18.
PLoS Pathog ; 11(2): e1004657, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25674795

RESUMEN

Most adenoviruses attach to host cells by means of the protruding fiber protein that binds to host cells via the coxsackievirus and adenovirus receptor (CAR) protein. Human adenovirus type 52 (HAdV-52) is one of only three gastroenteritis-causing HAdVs that are equipped with two different fiber proteins, one long and one short. Here we show, by means of virion-cell binding and infection experiments, that HAdV-52 can also attach to host cells via CAR, but most of the binding depends on sialylated glycoproteins. Glycan microarray, flow cytometry, surface plasmon resonance and ELISA analyses reveal that the terminal knob domain of the long fiber (52LFK) binds to CAR, and the knob domain of the short fiber (52SFK) binds to sialylated glycoproteins. X-ray crystallographic analysis of 52SFK in complex with 2-O-methylated sialic acid combined with functional studies of knob mutants revealed a new sialic acid binding site compared to other, known adenovirus:glycan interactions. Our findings shed light on adenovirus biology and may help to improve targeting of adenovirus-based vectors for gene therapy.


Asunto(s)
Adenovirus Humanos , Proteína de la Membrana Similar al Receptor de Coxsackie y Adenovirus , Glicoproteínas , Proteínas Virales , Tropismo Viral/fisiología , Acoplamiento Viral , Adenovirus Humanos/química , Adenovirus Humanos/fisiología , Secuencia de Bases , Línea Celular , Proteína de la Membrana Similar al Receptor de Coxsackie y Adenovirus/química , Proteína de la Membrana Similar al Receptor de Coxsackie y Adenovirus/metabolismo , Cristalografía por Rayos X , Glicoproteínas/química , Glicoproteínas/metabolismo , Humanos , Datos de Secuencia Molecular , Proteínas Virales/química , Proteínas Virales/metabolismo
19.
Scand J Gastroenterol ; 52(9): 1022-1028, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28562110

RESUMEN

BACKGROUND: Epidemiological studies of autoimmune hepatitis (AIH) show varying figures on prevalence and incidence, and data on the long-term prognosis are scarce. Objective To investigate the epidemiology, long-term prognosis and causes of death in a Swedish AIH cohort. MATERIAL AND METHODS: Data collected from 634 AIH patients were matched to the Cause of Death Registry, and survival analyses were made. Prevalence and incidence were calculated for university hospitals with full coverage of cases and compared to the County of Västerbotten in Northern Sweden. RESULTS: AIH point prevalence was 17.3/100,000 inhabitants in 2009, and the yearly incidence 1990-2009 was 1.2/100,000 inhabitants and year. The time between diagnosis and end of follow-up, liver transplantation or death was in median 11.3 years (range 0-51.5 years). Men were diagnosed earlier (p < .001) and died younger than women (p = .002). No gender differences were found concerning transplant-free, overall survival and liver-related death. Cirrhosis at diagnosis was linked to an inferior survival (p < .001). Liver-related death was the most common cause of death (32.7%). The relative survival started to diverge from the general population 4 years after diagnosis but a distinct decline was not observed until after more than 10 years. CONCLUSIONS: Long-term survival was reduced in patients with AIH. No gender difference regarding prognosis was seen but men died younger, probably as a result of earlier onset of disease. Cirrhosis at diagnosis was a risk factor for poor prognosis and the overall risk of liver-related death was increased.


Asunto(s)
Hepatitis Autoinmune/complicaciones , Hepatitis Autoinmune/mortalidad , Cirrosis Hepática/mortalidad , Trasplante de Hígado , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Causas de Muerte , Niño , Preescolar , Femenino , Humanos , Incidencia , Lactante , Recién Nacido , Cirrosis Hepática/cirugía , Masculino , Persona de Mediana Edad , Prevalencia , Sistema de Registros , Estudios Retrospectivos , Factores de Riesgo , Distribución por Sexo , Análisis de Supervivencia , Suecia/epidemiología , Adulto Joven
20.
Scand J Gastroenterol ; 52(2): 159-165, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27650916

RESUMEN

BACKGROUND AND AIM: Moderate alcohol consumption has been associated with a lower risk of disease severity in non-alcoholic fatty liver disease (NAFLD). It is unclear if this reflects current or lifetime drinking, or can be attributed to confounders such as diet and exercise. We evaluated the impact of lifetime alcohol consumption on fibrosis severity in NAFLD. METHODS: We prospectively enrolled 120 subjects with biopsy-proven NAFLD and through detailed questionnaires examined lifetime alcohol consumption, diet and physical activity. Main outcome measures were odds ratios (OR) for fibrosis stage, calculated through ordinal regression after adjustment for body mass index, diabetes mellitus type 2, smoking and age at biopsy. A biomarker for recent alcohol consumption, phosphatidyl ethanol (PEth) was sampled. RESULTS: An increase in median weekly alcohol consumption to a maximum of 13 drinks per week was associated with lower fibrosis stage (adjusted OR for each incremental unit, 0.86; 95% CI, 0.76-0.97; p = .017). The lowest risk for fibrosis was found with the lowes`t odds seen in the top quartile of alcohol consumption (aOR 0.23; 95% CI 0.08-0.66; p = .006). Adding soft drink and coffee consumptions, and physical activity to the model did not change the estimates. Subjects with PEth ≥0.3 µmol/L had higher ORs for a higher fibrosis stage (aOR 2.77; 95% CI 1.01-7.59; p = .047). CONCLUSION: Lifetime alcohol consumption with up to 13 units per week is associated with lower fibrosis stage in NAFLD. Elevated PEth is associated with higher stages of fibrosis.


Asunto(s)
Consumo de Bebidas Alcohólicas , Cirrosis Hepática/patología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/patología , Adulto , Anciano , Biomarcadores/sangre , Ácidos Grasos/sangre , Femenino , Fibrosis , Glicerofosfolípidos/sangre , Humanos , Hígado/patología , Cirrosis Hepática/etiología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Prospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Encuestas y Cuestionarios , Suecia , Adulto Joven
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