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Dive into the research topics where Juan I. Arenas is active.

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Featured researches published by Juan I. Arenas.


The Journal of Infectious Diseases | 2004

Hepatitis C Virus Quasi-Species Dynamics Predict Progression of Fibrosis after Liver Transplantation

Juan I. Arenas; Juan F. Gallegos-Orozco; Tomasz Laskus; Jeff Wilkinson; Amer Khatib; Carlos G. Fasola; Debra Adair; Marek Radkowski; Karen V. Kibler; Marek Nowicki; David D. Douglas; James W. Williams; George J. Netto; David C. Mulligan; Goran B. Klintmalm; Jorge Rakela; Hugo E. Vargas

BACKGROUND The dynamics of hepatitis C virus (HCV) quasi species in the E2 region may correlate with the course of infection after orthotopic liver transplantation (OLT). METHODS Thirty-four patients who underwent transplantation for HCV-related cirrhosis were studied. Serum and liver samples were available before OLT and at 1 week, 4 months, and 1 year after OLT. Patients were divided into group 1 (Knodell/Ishak fibrosis stage [FS] at 1 year, <2) and group 2 (FS at 1 year, > or =2). Complexity was estimated by the number of bands in a single-strand conformational polymorphism assay, whereas diversity was measured by Shannon entropy (SE) and median mobility shift (MMS) values derived from the heteroduplex mobility assay. Diversity dynamics were measured at transmission (before OLT vs. 1 week after OLT) and after OLT (1 week after OLT vs. 1 year after OLT). RESULTS Complexity was higher in group 1 patients than in group 2 patients before OLT (P<.02) and at 1 week after OLT (P<.04). Diversity decreased in group 1 at transmission, as measured by either SE (P<.01) or MMS (P<.04). However, diversity increased in this group after OLT, as measured by SE (P<.03) or MMS (P<.02). FS at 1 year after OLT correlated with transmission changes, as measured by SE (r=0.642, P<.0001) and MMS (r=0.443, P<.04), and with post-OLT changes (for SE: r=-0.583, P<.01; for MMS: r=-0.536, P<.01). CONCLUSIONS HCV complexity and diversity in the E2 region correlated with the severity of recurrence of HCV infection after OLT. Increased diversity of quasi species at transmission correlated with a higher FS at 1 year. However, increased diversity of quasi species in the post-OLT period correlated with a lower FS at 1 year. The dynamics of HCV quasi species in patients who undergo transplantation are predictive of outcome.


Hepatology | 2017

Treatment of hepatitis C virus infection in patients with cirrhosis and predictive value of model for end‐stage liver disease: Analysis of data from the Hepa‐C registry

Carlos Fernández Carrillo; S. Lens; Elba Llop; J.M. Pascasio; Javier Crespo; Juan I. Arenas; Inmaculada Fernández; Carme Baliellas; J.A. Carrión; Manuel de la Mata; Maria Buti; Lluis Castells; Agustín Albillos; Manuel Romero; Juan Turnes; Clara Pons; José María Moreno‐Planas; José Javier Moreno‐Palomares; Conrado M. Fernández-Rodríguez; Javier García-Samaniego; Martín Prieto; Miguel Fernández Bermejo; Javier Salmerón; Ester Badia; Magdalena Salcedo; José Ignacio Herrero; Rafael Granados; Michel Blé; Zoe Mariño; Jose Luis Calleja

Direct‐acting antiviral agents (DAAs) are highly effective and well tolerated in patients with chronic hepatitis C virus infection, including those with compensated cirrhosis. However, fewer data are available in patients with more advanced liver disease. Our retrospective, noninterventional, national, multicenter study in patients from the Spanish Hepa‐C registry investigated the effectiveness and safety of interferon‐free DAA regimens in patients with advanced liver disease, including those with decompensated cirrhosis, in routine practice (all currently approved regimens were registered). Patients transplanted during treatment or within 12 weeks of completing treatment were excluded. Among 843 patients with cirrhosis (Child‐Turcotte‐Pugh [CTP] class A, n = 564; CTP class B/C, n = 175), 90% achieved sustained virologic response 12 weeks after treatment (SVR12). Significant differences in SVR12 and relapse rates were observed between CTP class A and CTP class B/C patients (94% versus 78%, and 4% versus 14%, respectively; both P < 0.001). Serious adverse events (SAEs) were more common in CTP class B/C versus CTP class A patients (50% versus 12%, respectively; P < 0.001). Incident decompensation was the most common serious adverse event (7% overall). Death rate during the study period was 16/843 (2%), significantly higher among CTP class B/C versus CTP class A patients (6.4% versus 0.9%; P < 0.001). Baseline Model for End‐Stage Liver Disease (MELD) score alone (cut‐off 18) was the best predictor of survival. Conclusion: Patients with decompensated cirrhosis receiving DAAs present lower response rates and experience more SAEs. In this setting, a MELD score ≥18 may help clinicians to identify those patients with a higher risk of complications and to individualize treatment decisions. (Hepatology 2017;65:1810‐1822).


Clinical Gastroenterology and Hepatology | 2017

Real-World Effectiveness and Safety of Oral Combination Antiviral Therapy for Hepatitis C Virus Genotype 4 Infection

Javier Crespo; Jose Luis Calleja; Inmaculada Fernández; Begoña Sacristán; Belén Ruiz-Antorán; Javier Ampuero; Marta Hernández-Conde; J. García-Samaniego; F. Gea; Maria Buti; J. Cabezas; Sabela Lens; Rosa Maria Morillas; J.R. Salcines; J.M. Pascasio; Juan Turnes; Federico Sáez-Royuela; Juan I. Arenas; Diego Rincón; Martín Prieto; F. Jorquera; Juan José Sánchez Ruano; C.A. Navascués; Esther Molina; Adolfo Gallego Moya; José María Moreno-Planas; Silvia Montoliu; Miguel A. Serra; R.J. Andrade; Conrado Fernández

&NA; Patients with hepatitis C virus (HCV) genotype 4 infection are poorly represented in clinical trials of second‐generation direct‐acting antiviral agents (DAAs). More data are needed to help guide treatment decisions. We investigated the effectiveness and safety of DAAs in patients with genotype 4 infection in routine practice. In this cohort study, HCV genotype 4‐infected patients treated with ombitasvir/paritaprevir/ritonavir (OMV/PTVr) + ribavirin (RBV) (n=122) or ledipasvir/sofosbuvir (LDV/SOF) ± RBV (n=130) included in a national database were identified and prospectively followed up. Demographic, clinical and virologic data and serious adverse events (SAEs) were analyzed. Differences between treatment groups mean that data cannot be compared directly. Overall sustained virologic response at Week 12 post treatment (SVR12) was 96.2% with OMV/PTVr+RBV and 95.4% with LDV/SOF±RBV. In cirrhotic patients, SVR12 was 91.2% with OMV/PTVr+RBV and 93.2% with LDV/SOF±RBV. There was no significant difference in SVR12 according to degree of fibrosis in either treatment group (P = .243 and P = .244, respectively). On multivariate analysis, baseline albumin <3.5 g/dL (OMV/PTVr) and bilirubin >2 mg/dL (both cohorts) were significantly associated with failure to achieve SVR (P < .05). Rates of SAEs and SAE‐associated discontinuation were 5.7% and 2.5%, respectively, in the OMV/PTVr subcohort and 4.6% and 0.8%, respectively, in the LDV/SOF subcohort. DAA‐based regimens returned high rates of SVR12, comparable to limited data from clinical trials, in cirrhotic and non‐cirrhotic HCV genotype 4 patients managed in a realworld setting. Safety profiles of both regimens were good and comparable to those reported for other HCV genotypes.


Journal of Viral Hepatitis | 2006

Selection of different 5′ untranslated region hepatitis C virus variants during post-transfusion and post-transplantation infection

Juan F. Gallegos-Orozco; Juan I. Arenas; Hugo E. Vargas; Karen V. Kibler; Jeffrey Wilkinson; Marek Nowicki; Marek Radkowski; J. Nasseri; Jorge Rakela; Tomasz Laskus

Summary.  Background:  Hepatitis C virus (HCV) translation is initiated in a cap‐independent manner by an internal ribosome entry site (IRES) located within the 5′ untranslated region (5′UTR). Sequence changes in this region could affect translation efficiency and presumably viral replication.


Clinics in Liver Disease | 2003

The use of virologically compromised organs in liver transplantation

Hector Rodriguez-Luna; Juan I. Arenas; Hugo E. Vargas

The present organ donor crisis has led to accepted use of organs from donors infected with hepatitis C virus (HCV) and hepatitis B virus (HBV). Although capable of transmitting disease, these grafts offer opportunities to expand the donor pool for certain populations. Anti-HBc positive grafts can be used if care is taken to provide prophylaxis. Good quality grafts from HCV+ donors may be used in recipients who are themselves HCV+ with good outcomes.


Gastroenterología y Hepatología | 2017

Original ArticleThe ART-SCORE is not an effective tool for optimizing patient selection for DEB-TACE retreatment. A multicentre Spanish studyEl ART-SCORE no es una herramienta eficaz para optimizar la selección de pacientes para el tratamiento con DEB-TACE. Estudio multicéntrico español

Maria Pipa-Muñiz; Lluis Castells; Sonia Pascual; Javier Fernández-Castroagudín; Iratxe Díez-Miranda; Javier Irurzun; Roberto Díaz-Beveridge; María Senosiaín; Juan I. Arenas; Manuel de la Mata; Juan Turnes; María Isabel Monge-Romero; Daniel Pérez-Enguix; Javier Bustamante-Schneider; Nora Otegui; Esther Molina-Pérez; José Eduardo Rodríguez-Menéndez; María Varela

Introduction The appropriate selection of hepatocellular carcinoma (HCC) patients who are eligible for transarterial chemoembolization (TACE) remains a challenge. The ART score has recently been proposed as a method of identifying patients who are eligible or not for a second TACE procedure.


Liver Transplantation | 2003

The use of hepatitis C-infected grafts in liver transplantation

Juan I. Arenas; Hugo E. Vargas; Jorge Rakela


Gastroenterology Clinics of North America | 2004

Hepatitis C virus antiviral therapy in patients with cirrhosis

Juan I. Arenas; Hugo E. Vargas


Hepatology | 2003

769 Rejection treatment modifies HCV quasispecies evolution after liver transplantation

Juan I. Arenas; Tomasz Laskus; Jeff Wilkinson; Juan F. Gallegos; Carlos G. Fasola; Debra Adair; Marek Radowski; Karen V. Kibler; David D. Douglas; James E. Williams; George J. Netto; David C. Mulligan; Goran B. Klintmalm; Jorge Rakela; Hugo E. Vargas


Liver Transplantation | 2002

Is D‐penicillamine useful in fulminat Wilson's disease?

Jorge Rakela; Hugo E. Vargas; Juan I. Arenas

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Juan Turnes

University of Barcelona

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Marek Radkowski

Medical University of Warsaw

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J.M. Pascasio

Spanish National Research Council

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