96 results on '"Isaac Ruiz"'
Search Results
2. A real-world experience of SARS-CoV-2 infection in a tertiary referral centre of Montréal: Unexpected low prevalence and low mortality
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Geneviève Huard, Victor Ferreira, Bernard Willems, Florence Correal, Denis Marleau, Marc Bilodeau, Catherine Vincent, Isaac Ruiz, Julien Bissonnette, Alexandre Mathieu, Daniel Corsilli, Claire Fournier, Jean-Pierre Villeneuve, Hélène Castel, Jeanne-Marie Giard, Dominic Martel, and Daphna Fenyves
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medicine.medical_specialty ,Cirrhosis ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Tertiary referral centre ,medicine.medical_treatment ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,General Medicine ,Liver transplantation ,Chronic liver disease ,medicine.disease ,respiratory tract diseases ,Internal medicine ,medicine ,In patient ,business - Abstract
BACKGROUND: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in patients with chronic liver disease (CLD) and liver transplant (LT) recipients remains a concern. The aim of this study was to report the impact of coronavirus disease 2019 (COVID-19) infection among patients at the tertiary health care centre Centre hospitalier de l’Université de Montréal (CHUM) during the first wave of the SARS-CoV-2 pandemic. METHODS: This real-world, retrospective cohort included all patients admitted to our liver unit and/or seen as an outpatient with CLD with or without cirrhosis and/or LT recipients who tested positive to SARS-CoV-2 infection. Cases were considered positive as defined by the detection of SARS-CoV-2 by reverse-transcription polymerase chain reaction (RT-PCR) on nasopharyngeal swabs. RESULTS: Between April 1 and July 31, 2020, 5,637 were admitted to our liver unit and/or seen as outpatient. Among them, 42 were positive for SARS-CoV-2. Twenty-two patients had CLD without cirrhosis while 16 patients had cirrhosis at the time of the infection (13, 2, and 1 with Child–Pugh A, B, and C scores, respectively). Four were LT recipients. Overall, 15 of 42 patients (35.7%) were hospitalized; among them, 7 of 42 (16.7%) required respiratory support and 4 of 42 (9.5%) were transferred to the intensive care unit. Only 4 of 42 (9.5%) patients died: 2 with CLD without cirrhosis and 2 with CLD with cirrhosis. Overall survival was 90.5%. CONCLUSION: This real-world study demonstrates an unexpectedly low prevalence and low mortality in the context of SARS-CoV-2 infection among patients with CLD with or without cirrhosis and LT recipients.
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- 2021
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3. Macrophage autophagy protects against hepatocellular carcinogenesis in mice
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Anthony, Deust, Marie-Noële, Chobert, Vanessa, Demontant, Guillaume, Gricourt, Timothé, Denaës, Allan, Thiolat, Isaac, Ruiz, Christophe, Rodriguez, Jean-Michel, Pawlotsky, and Fatima, Teixeira-Clerc
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Mice, Knockout ,Mice ,Carcinoma, Hepatocellular ,Liver ,Gene Expression Profiling ,Macrophages ,Science ,Liver Neoplasms ,Autophagy ,Animals ,Medicine - Abstract
Autophagy is a lysosomal degradation pathway of cellular components that regulates macrophage properties. Macrophages are critically involved in tumor growth, metastasis, angiogenesis and immune suppression. Here, we investigated whether macrophage autophagy may protect against hepatocellular carcinoma (HCC). Experiments were performed in mice with deletion of the autophagy gene Atg5 in the myeloid lineage (ATG5Mye−/− mice) and their wild-type (WT) littermates. As compared to WT, ATG5Mye−/− mice were more susceptible to diethylnitrosamine (DEN)-induced hepatocarcinogenesis, as shown by enhanced tumor number and volume. Moreover, DEN-treated ATG5Mye−/− mice exhibited compromised immune cell recruitment and activation in the liver, suggesting that macrophage autophagy invalidation altered the antitumoral immune response. RNA sequencing showed that autophagy-deficient macrophages sorted from DEN mice are characterized by an enhanced expression of immunosuppressive markers. In vitro studies demonstrated that hepatoma cells impair the autophagy flux of macrophages and stimulate their expression of programmed cell death-ligand 1 (PD-L1), a major regulator of the immune checkpoint. Moreover, pharmacological activation of autophagy reduces hepatoma cell-induced PD-L1 expression in cultured macrophages while inhibition of autophagy further increases PD-L1 expression suggesting that autophagy invalidation in macrophages induces an immunosuppressive phenotype. These results uncover macrophage autophagy as a novel protective pathway regulating liver carcinogenesis.
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- 2021
4. Nano-scale aluminium interaction in synthetic hydrated calcium silicate gel studied by 29Si MAS-NMR
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Alberto Isaac Ruiz, Encarnación Reyes, Cristina Argiz, Miguel Angel de la Rubia, and Amparo Moragues
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Mechanics of Materials ,Ceramics and Composites ,Industrial and Manufacturing Engineering - Published
- 2022
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5. Non-invasive diagnosis and follow-up of chronic infection with Hepatitis C Virus
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Stéphane Chevaliez, Sarah Shili-Masmoudi, Lucile Moga, Isaac Ruiz, Nathalie Ganne-Carrié, Albert Tran, M. Bourlière, Christophe Bureau, Victor de Lédinghen, Alain Luciani, Hôpital l'Archet, Centre Hospitalier Universitaire de Nice (CHU Nice), Hôpital Haut-Lévêque [CHU Bordeaux], CHU Bordeaux [Bordeaux], Bordeaux Research In Translational Oncology [Bordeaux] (BaRITOn), Université de Bordeaux (UB)-CHU Bordeaux [Bordeaux]-Institut National de la Santé et de la Recherche Médicale (INSERM), Hôpital Beaujon [AP-HP], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Hôpital Henri Mondor, Institut Mondor de Recherche Biomédicale (IMRB), Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR10-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Hôpital Avicenne [AP-HP], Université Sorbonne Paris Nord, Hôpital Rangueil, CHU Toulouse [Toulouse], Hôpital Saint-Joseph [Marseille], Sciences Economiques et Sociales de la Santé & Traitement de l'Information Médicale (SESSTIM - U1252 INSERM - Aix Marseille Univ - UMR 259 IRD), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Centre Hospitalier Universitaire de Toulouse (CHU Toulouse), and Malbec, Odile
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Liver Cirrhosis ,HBsAg ,medicine.medical_specialty ,Hepatitis C virus ,[SDV]Life Sciences [q-bio] ,Hepacivirus ,medicine.disease_cause ,Gastroenterology ,Virus ,Fibrosis ,Internal medicine ,medicine ,Humans ,Hepatology ,business.industry ,Liver Diseases ,virus diseases ,Hepatitis C, Chronic ,medicine.disease ,Hepatitis C ,digestive system diseases ,[SDV] Life Sciences [q-bio] ,Chronic infection ,Liver ,HBeAg ,Hepatocellular carcinoma ,Elasticity Imaging Techniques ,Portal hypertension ,Persistent Infection ,business ,Follow-Up Studies - Abstract
Diagnosis of chronic hepatitis B virus (HBV) infection, initial staging of infection and monitoring of treated and untreated patients are mainly based on clinical, biological and imaging criteria allowing a complete non-invasive management for the majority of patients. Along to the conventional virological tools, rapid diagnostic tests and blotting paper tests for HBV DNA are validated alternatives. After diagnosis, the initial work-up should include HIV, HCV and HDV serologies, HBeAg status, and HBsAg and HBV DNA quantification. Assessment of severity (inflammation and fibrosis) is based on ALT serum levels and non-invasive evaluation of liver fibrosis by elastography or blood tests, which must be interpreted cautiously using specific cut-offs and taking into account ALT levels. Taken together, these parameters allow disease classification and treatment decision. Decision of hepatocellular carcinoma screening by ultra-sound every six months may be difficult in non-cirrhotic patients and the use of risk-scores such as PAGE-B is encouraged. Chronic HBV infection often has a dynamic and often unpredictable profile and regular monitoring is mandatory. In untreated patients, regular (3-12 months) follow-up should include ALT and HBV DNA serum levels. Periodical HBsAg quantification and non-invasive evaluation of liver fibrosis may refine disease outcome and prognosis. In treated patients, checking efficacy is mainly based on HBV DNA negativity. In patients with advanced fibrosis, evolution of liver stiffness can be useful for portal hypertension evaluation, but its improvement should not be considered to stop hepatocellular carcinoma screening. Finally, new parameters (HBV RNA, HBcrAg) are promising but their use is still restricted for research.
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- 2022
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6. Detection of High Energy Ionizing Radiation using Deeply Depleted Graphene-Oxide-Semiconductor Junctions
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Isaac Ruiz, Gyorgy Vizkelethy, Anthony E. McDonald, Stephen W. Howell, Paul M. Thelen, Michael D. Goldflam, and Thomas E. Beechem
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Condensed Matter - Materials Science ,Condensed Matter - Mesoscale and Nanoscale Physics ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,General Physics and Astronomy ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences - Abstract
Graphene's linear bandstructure and two-dimensional density of states provide an implicit advantage for sensing charge. Here, these advantages are leveraged in a deeply depleted graphene-oxide-semiconductor (D2GOS) junction detector architecture to sense carriers created by ionizing radiation. Specifically, the room temperature response of the silicon-based D2GOS junction is analyzed during irradiation with 20 MeV Si4+ ions. Detection was demonstrated for doses ranging from 12-1200 ions with device functionality maintained with no substantive degradation. To understand the device response, D2GOS pixels were characterized post-irradiation via a combination of electrical characterization, Raman spectroscopy, and photocurrent mapping. This combined characterization methodology underscores the lack of discernible damage caused by irradiation to the graphene while highlighting the nature of interactions between the incident ions and the silicon absorber., Comment: 15 pages, 4 figures
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- 2022
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7. Hepatic evaluation of patients with telomeropathies
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Olivia Portolese, Isaac Ruiz, Julien Bissonnette, Julian Hercun, Helene Castel, Bernard Willems, Marc Bilodeau, Jeanne-Marie Giard, Catherine Vincent, Ziad Hassoun, Geneviève Soucy, Bich Ngoc Nguyen, Basil Nasir, Pasquel Ferraro, Julie Morisset, Charles Poirier, and Genevieve Huard
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Hepatology - Published
- 2022
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8. Small-Molecule Inhibitors of Cyclophilins Block Opening of the Mitochondrial Permeability Transition Pore and Protect Mice From Hepatic Ischemia/Reperfusion Injury
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Muriel Gelin, Fred Allemand, Cong Trung Nguyen, Mathieu Panel, Abdelhakim Ahmed-Belkacem, Bijan Ghaleh, Rozenn Brillet, Isaac Ruiz, Julien Calderaro, Fouad Lafdil, Jean-François Guichou, Fatima Teixeira-Clerc, Didier Morin, Jean-Michel Pawlotsky, Institut Mondor de Recherche Biomédicale (IMRB), Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR10-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Centre de Biochimie Structurale [Montpellier] (CBS), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), morin, didier, and Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Santé et de la Recherche Médicale (INSERM)
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Male ,0301 basic medicine ,Isomerase activity ,[SDV.MHEP.CHI] Life Sciences [q-bio]/Human health and pathology/Surgery ,Ischemia ,Mitochondria, Liver ,[SDV.MHEP.CHI]Life Sciences [q-bio]/Human health and pathology/Surgery ,Pharmacology ,Mitochondrion ,Mitochondrial Membrane Transport Proteins ,Mouse model ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,Animals ,Humans ,Calcium Signaling ,Enzyme Inhibitors ,Inner mitochondrial membrane ,Cells, Cultured ,Mice, Knockout ,Hepatology ,Mitochondrial Permeability Transition Pore ,Chemistry ,Liver Diseases ,MPTP ,Gastroenterology ,PPIF ,[SDV.MHEP.HEG]Life Sciences [q-bio]/Human health and pathology/Hépatology and Gastroenterology ,medicine.disease ,[SDV.MHEP.HEG] Life Sciences [q-bio]/Human health and pathology/Hépatology and Gastroenterology ,3. Good health ,PPIase activity ,Mice, Inbred C57BL ,Disease Models, Animal ,030104 developmental biology ,Liver ,Mitochondrial permeability transition pore ,Cytoprotection ,[SDV.SP.PHARMA] Life Sciences [q-bio]/Pharmaceutical sciences/Pharmacology ,Reperfusion Injury ,[SDV.SP.PHARMA]Life Sciences [q-bio]/Pharmaceutical sciences/Pharmacology ,030211 gastroenterology & hepatology ,Drug ,Mitochondrial Swelling ,Reperfusion injury ,Cyclophilin D ,Signal Transduction - Abstract
International audience; Background & Aims: Hepatic ischemia-reperfusion injury is a complication of liver surgery that involves mitochondrial dysfunction resulting from mitochondrial permeability transition pore (mPTP) opening. Cyclophilin D (PPIF or CypD) is a peptidyl-prolyl cis-trans isomerase that regulates mPTP opening in the inner mitochondrial membrane. We investigated whether and how recently created small-molecule inhibitors of CypD prevent opening of the mPTP in hepatocytes and the resulting effects in cell models and livers of mice undergoing ischemia/reperfusion injuryMethods: We measured the activity of 9 small-molecule inhibitors of cyclophilins in an assay of CypD activity. The effects of the small-molecule CypD inhibitors or vehicle on mPTP opening were assessed by measuring mitochondrial swelling and calcium retention in isolated liver mitochondria from C57BL/6J (wild-type) and Ppif–/– (CypD knockout) mice and in primary mouse and human hepatocytes by fluorescence microscopy. We induced ischemia/reperfusion injury in livers of mice given a small-molecule CypD inhibitor or vehicle before and during reperfusion and collected samples of blood and liver for histologic analysis.Results: The compounds inhibited peptidyl-prolyl isomerase activity (half maximal inhibitory concentration values, 0.2–16.2 μmol/L) and, as a result, calcium-induced mitochondrial swelling, by preventing mPTP opening (half maximal inhibitory concentration values, 1.4–132 μmol/L) in a concentration-dependent manner. The most potent inhibitor (C31) bound CypD with high affinity and inhibited swelling in mitochondria from livers of wild-type and Ppif–/– mice (indicating an additional, CypD-independent effect on mPTP opening) and in primary human and mouse hepatocytes. Administration of C31 in mice with ischemia/reperfusion injury before and during reperfusion restored hepatic calcium retention capacity and oxidative phosphorylation parameters and reduced liver damage compared with vehicle.Conclusions:Recently created small-molecule inhibitors of CypD reduced calcium-induced swelling in mitochondria from mouse and human liver tissues. Administration of these compounds to mice during ischemia/reperfusion restored hepatic calcium retention capacity and oxidative phosphorylation parameters and reduced liver damage. These compounds might be developed to protect patients from ischemia/reperfusion injury after liver surgery or for other hepatic or nonhepatic disorders related to abnormal mPTP opening.
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- 2019
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9. Interface Defect Engineering for Improved Graphene-Oxide-Semiconductor Junction Photodetectors
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Sean W. Smith, Raktim Sarma, Stephen W. Howell, Joshua Shank, Peter Dickens, Thomas E. Beechem, Elizabeth A. Paisley, Bruce L. Draper, Isaac Ruiz, and Michael Goldflam
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Materials science ,business.industry ,Graphene ,Interface (computing) ,Detector ,Oxide ,Photodetector ,Defect engineering ,Charge (physics) ,Photodetection ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Optoelectronics ,General Materials Science ,business - Abstract
The deeply depleted graphene-oxide-semiconductor (D2GOS) junction detector provides an effective architecture for photodetection, enabling direct readout of photogenerated charge. Because of an inh...
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- 2019
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10. One-year outcome of patients with cirrhosis who developed spontaneous bacterial empyema: A cohort study
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José Miguel Jiménez-Gutiérrez, Antonio Olivas-Martinez, Ignacio García-Juárez, and Isaac Ruiz
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Liver Cirrhosis ,medicine.medical_specialty ,Cirrhosis ,business.industry ,medicine.medical_treatment ,Gastroenterology ,Retrospective cohort study ,Liver transplantation ,Middle Aged ,medicine.disease ,Severity of Illness Index ,Empyema ,Cohort Studies ,End Stage Liver Disease ,Spontaneous bacterial peritonitis ,Model for End-Stage Liver Disease ,Internal medicine ,medicine ,Humans ,business ,Survival rate ,Cohort study ,Retrospective Studies - Abstract
Background & aims Spontaneous bacterial empyema (SBE) is defined as the spontaneous infection of hepatic hydrothorax. It is a rare infectious complication of portal hypertension in cirrhotic patients. The aim of this study was to evaluate the outcomes in patients diagnosed with SBE compared to cirrhotic patients without this complication. Methods We performed a retrospective cohort study of cirrhotic patients from a tertiary care center. The primary outcome was time to death or liver transplantation within one year after diagnosis of infection. We integrated three groups: patients with SBE (Group A), patients with spontaneous bacterial peritonitis (SBP, Group B), and cirrhotic patients without SBP/SBE (Group C), matched by age, MELD-Na score, and year of infection. Outcome was analyzed using a Cox regression model adjusting for cardiovascular risk factors and MELD-Na. Results Between January 1999 and February 2019, 4829 patients with cirrhosis were identified. Among them, 73 (1.5%) had a HH of whom 22 (30.1%) were diagnosed with SBE. Median age of the patients with SBE was 58 years (IQR 52-64), 11 patients (50%) were men, median Child Pugh score was 10 (IQR 8-11) and median MELD-Na was 21 (IQR 15-27). TFS was 9.1% (2/22), vs 41% (18/44) vs 52.2% (23/44) in Group A, B and C, respectively (log rank test p Conclusion Our results suggest that patients with SBE had a lower one-year survival rate. Patients who develop SBE should have prompt referral for transplant evaluation. SBE might emerge as new indication that could benefit from MELD exception points. This article is protected by copyright. All rights reserved.
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- 2021
11. Abdominal Skin Injury due to Non-Target Embolization of Hepatocellular Carcinoma Vascularized by the Internal Mammary Artery
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Isaac, Ruiz, Nadine S, Maalouf, Ahmed, Bentridi, Ricardo, Holderbaum do Amaral, Damien, Olivié, Pierre, Perreault, Daphna, Fenyves, Ashley, Hill, and Louis, Bouchard
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Carcinoma, Hepatocellular ,Liver Neoplasms ,Humans ,Chemoembolization, Therapeutic ,Mammary Arteries ,Embolization, Therapeutic ,Skin - Published
- 2021
12. A Phenyl-Pyrrolidine Derivative Reveals a Dual Inhibition Mechanism of Myocardial Mitochondrial Permeability Transition Pore, Which Is Limited by Its Myocardial Distribution
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Jean-François Guichou, Bijan Ghaleh, Mathieu Panel, Isaac Ruiz, Jean-Michel Pawlotsky, Didier Morin, Abdelhakim Ahmed-Belkacem, Institut Mondor de Recherche Biomédicale (IMRB), and Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR10-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)
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0301 basic medicine ,Male ,Pyrrolidines ,[SDV]Life Sciences [q-bio] ,Pharmacology ,Mitochondrion ,Mitochondria, Heart ,03 medical and health sciences ,chemistry.chemical_compound ,Mice ,0302 clinical medicine ,Cytosol ,In vivo ,Animals ,Heart metabolism ,Cyclophilin ,ComputingMilieux_MISCELLANEOUS ,Cardioprotection ,Mitochondrial Permeability Transition Pore ,MPTP ,Myocardium ,Biological Transport ,Heart ,Mice, Inbred C57BL ,030104 developmental biology ,chemistry ,Mitochondrial permeability transition pore ,cardiovascular system ,Molecular Medicine ,030217 neurology & neurosurgery ,Ex vivo - Abstract
Mitochondrial permeability transition pore (mPTP) opening is a key event in cell death during myocardial ischemia reperfusion. Inhibition of its modulator cyclophilin D (CypD) by cyclosporine A (CsA) reduces ischemia-reperfusion injury. The use of cyclosporine A in this indication is debated; however, targeting mPTP remains a major goal to achieve. We investigated the protective effects of a new original small-molecule cyclophilin inhibitor C31, which was specifically designed to target CypD. CypD peptidylprolyl cis-trans isomerase (PPIase) activity was assessed by the standard chemotrypsin-coupled assay. The effects of C31 on mPTP opening were investigated in isolated mouse cardiac mitochondria by measuring mitochondrial swelling and calcium retention capacity (CRC) in rat H9C2 cardiomyoblasts and in adult mouse cardiomyocytes by fluorescence microscopy in isolated perfused mouse hearts and ex vivo after drug infusion in mice. C31 potently inhibited CypD PPIase activity and mitochondrial swelling. C31 was more effective at increasing mitochondrial CRC than CsA and was still able to increase CRC in Ppif−/− (CypD-inactivated) cardiac mitochondria. C31 delayed both mPTP opening and cell death in cardiomyocytes subjected to hypoxia reoxygenation. However, high concentrations of both drugs were necessary to reduce mPTP opening in isolated perfused hearts, and neither CsA nor C31 inhibited mPTP opening in heart after in vivo infusion, underlying the importance of myocardial drug distribution for cardioprotection. C31 is an original inhibitor of mPTP opening involving both CypD-dependent and -independent mechanisms. It constitutes a promising new cytoprotective agent. Optimization of its pharmacokinetic properties is now required prior to its use against cardiac ischemia-reperfusion injury. SIGNIFICANCE STATEMENT This study demonstrates that the new cyclophilin inhibitor C31 potently inhibits cardiac mitochondrial permeability transition pore (mPTP) opening in vitro and ex vivo. The dual mechanism of action of C31 allows the prevention of mPTP opening beyond cyclophilin D inhibition. Further development of the compound might bring promising drug candidates for cardioprotection. However, the lack of effect of both C31 and cyclosporine A after systemic administration demonstrates the difficulties of targeting myocardial mitochondria in vivo and should be taken into account in cardioprotective strategies.
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- 2021
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13. Interpretation of the Modification of the C-S-H Structures When Aluminium is Incorporated: 29si Mas-Rmn
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Alberto Isaac Ruiz Soto, Encarnación Reyes, Cristina Argiz, Miguel Angel de la Rubia, and Amparo Moragues
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History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2021
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14. Outcomes following SARS-CoV-2 infection in liver transplant recipients: an international registry study
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Eleanor Barnes, Isaac Ruiz, Alfred S. Barritt, Matthew J. Armstrong, Hannes Hagström, Ponni V. Perumalswami, Costica Aloman, Renumathy Dhanasekaran, Erica J. Brenner, Nneka N. Ufere, Andrew M. Moon, James Kennedy, Carolyn Mercer, Aileen Marshall, Tamsin Cargill, Gwilym J. Webb, Steven Masson, Maria Andreea Catana, Thomas Marjot, Jonathan Cook, Sarang Thaker, and Ignacio García-Juárez
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medicine.medical_specialty ,Hepatology ,business.industry ,medicine.medical_treatment ,Gastroenterology ,Liver transplantation ,medicine.disease ,Intensive care unit ,Comorbidity ,law.invention ,Transplantation ,03 medical and health sciences ,0302 clinical medicine ,law ,030220 oncology & carcinogenesis ,Intensive care ,Internal medicine ,Cohort ,medicine ,030211 gastroenterology & hepatology ,business ,Survival analysis ,Cohort study - Abstract
Background Despite concerns that patients with liver transplants might be at increased risk of adverse outcomes from COVID-19 because of coexisting comorbidities and use of immunosuppressants, the effect of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection on this patient group remains unclear. We aimed to assess the clinical outcomes in these patients. Methods In this multicentre cohort study, we collected data on patients with laboratory-confirmed SARS-CoV-2 infection, who were older than 18 years, who had previously received a liver transplant, and for whom data had been submitted by clinicians to one of two international registries (COVID-Hep and SECURE-Cirrhosis) at the end of the patient's disease course. Patients without a known hospitalisation status or mortality outcome were excluded. For comparison, data from a contemporaneous cohort of consecutive patients with SARS-CoV-2 infection who had not received a liver transplant were collected from the electronic patient records of the Oxford University Hospitals National Health Service Foundation Trust. We compared the cohorts with regard to several outcomes (including death, hospitalisation, intensive care unit [ICU] admission, requirement for intensive care, and need for invasive ventilation). A propensity score-matched analysis was done to test for an association between liver transplant and death. Findings Between March 25 and June 26, 2020, data were collected for 151 adult liver transplant recipients from 18 countries (median age 60 years [IQR 47–66], 102 [68%] men, 49 [32%] women) and 627 patients who had not undergone liver transplantation (median age 73 years [44–84], 329 [52%] men, 298 [48%] women). The groups did not differ with regard to the proportion of patients hospitalised (124 [82%] patients in the liver transplant cohort vs 474 [76%] in the comparison cohort, p=0·106), or who required intensive care (47 [31%] vs 185 [30%], p=0·837). However, ICU admission (43 [28%] vs 52 [8%], p Interpretation Liver transplantation was not independently associated with death, whereas increased age and presence of comorbidities were. Factors other than transplantation should be preferentially considered in relation to physical distancing and provision of medical care for patients with liver transplants during the COVID-19 pandemic. Funding European Association for the Study of the Liver, US National Institutes of Health, UK National Institute for Health Research.
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- 2020
15. Enhancing Graphene Plasmonic Device Performance via its Dielectric Environment
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Amun Jarzembski, Isaac Ruiz, Aleem Siddiqui, Thomas E. Beechem, and Michael Goldflam
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Materials science ,Phonon ,business.industry ,Graphene ,Infrared ,Physics::Optics ,General Physics and Astronomy ,Dielectric ,law.invention ,law ,Dispersion (optics) ,Spectral width ,Physics::Atomic and Molecular Clusters ,Optoelectronics ,Reflection coefficient ,business ,Plasmon - Abstract
Graphene plasmons provide a compelling avenue toward chip-scale dynamic tuning of infrared light. Dynamic tunability emerges through controlled alterations in the optical properties of the system defining graphene's plasmonic dispersion. Typically, electrostatic induced alterations of the carrier concentration in graphene working in conjunction with mobility have been considered the primary factors dictating plasmonic tunability. We find here that the surrounding dielectric environment also plays a primary role, dictating not just the energy of the graphene plasmon but so too the magnitude of its tuning and spectral width. To arrive at this conclusion, poles in the imaginary component of the reflection coefficient are used to efficiently survey the effect of the surrounding dielectric on the tuning of the graphene plasmon. By investigating several common polar materials, optical phonons (i.e., the Reststrahlen band) of the dielectric substrate are shown to appreciably affect not only the plasmon's spectral location but its tunability, and its resonance shape as well. In particular, tunability is maximized when the resonances are spectrally distant from the Reststrahlen band, whereas sharp resonances (i.e., high-$Q$) are achievable at the band's edge. These observations both underscore the necessity of viewing the dielectric environment in aggregate when considering the plasmonic response derived from two-dimensional materials and provide heuristics to design dynamically tunable graphene-based infrared devices.
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- 2020
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16. Data-Driven Inference of COVID-19 Clinical Prognosis
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Dagoberto Pulido, Isaac Ruiz, Joaquin Salas, and Omar Montoya
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Artificial neural network ,Computer science ,business.industry ,Inference ,Construct (python library) ,Machine learning ,computer.software_genre ,Data-driven ,Random forest ,Support vector machine ,Relevance (information retrieval) ,Artificial intelligence ,Risk assessment ,business ,computer - Abstract
Knowing the most likely clinical prognosis for a patient infected with SARS-Cov-2 could offer guidelines for tracking their medical evolution, improving attention, and assigning resources. Aiming to assess a patient’s status quantitatively, we explore the analysis of existing clinical information using data-driven methods. Our goal is to extract the characteristics distinguishing between those COVID-19 patients that improve and those who die. In our approach, we select the relevant features using the algorithm of Boruta, a wrapper framework that takes input from classifiers generating relevance assessment of the predictors. Using the extracted features, we train machine learning classifiers, including Random Forests, Support Vector Machine, Extreme Gradient Boosting, and Neural Networks. We assess the performance of the classifiers using Precision-Recall and ROC analysis, establishing the ranges at which risk assessment permits effective decision-making. Our research highlights that local regions present unique sets of essential features, that it is possible to construct effective classifiers based on clinical data, and that an ensemble of classifiers results in the best performing discriminant.
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- 2020
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17. Frequent Antiviral Treatment Failures in Patients Infected With Hepatitis C Virus Genotype 4, Subtype 4r
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Slim Fourati, Christophe Hézode, Christophe Rodriguez, Isaac Ruiz, Stéphane Chevaliez, Jean-Michel Pawlotsky, Alexandre Soulier, and Lila Poiteau
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Adult ,Male ,0301 basic medicine ,Ledipasvir ,Daclatasvir ,Genotype ,Sofosbuvir ,Hepatitis C virus ,Population ,Genome, Viral ,Hepacivirus ,medicine.disease_cause ,Antiviral Agents ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,Humans ,Treatment Failure ,education ,NS5A ,NS5B ,Aged ,Aged, 80 and over ,education.field_of_study ,Hepatology ,business.industry ,Middle Aged ,Hepatitis C ,Virology ,030104 developmental biology ,chemistry ,Female ,030211 gastroenterology & hepatology ,business ,medicine.drug - Abstract
Hepatitis C virus (HCV) genotype 4 is highly heterogeneous. HCV subtype 4r has been suggested to be less responsive to direct-acting antiviral (DAA) drug treatment than other genotype 4 subtypes. Among 537 DAA-treated patients who experienced a virological failure (VF) in France between 2015 and 2018, 121 (22.5%) were infected with genotype 4 and 27 of them (22.3%) with subtype 4r; subtype 4r was thus over-represented as compared to its prevalence in the French general population. Population sequencing of the nonstructural protein (NS) 3, NS5A, and NS5B genes was performed in all subtype 4r patients at treatment failure and in 6 at baseline, whereas full-length HCV genome sequencing was performed in two baseline and three treatment failure samples by means of an original shotgun metagenomics method based on deep sequencing. At treatment failure, all subtype 4r patients harbored two to three dominant NS5A resistance-associated substitutions (RASs), including at least L28A/C/I/M/V and L30R. Among 13 patients exposed to sofosbuvir and an NS5A inhibitor (daclatasvir, ledipasvir, or velpatasvir), 5 (38.5%) also harbored NS5B S282C/T RASs at treatment failure. An additional patient harbored S282C/T RASs at treatment failure by deep sequencing. Prevalence of S282C/T RASs at treatment failure was significantly higher in patients infected with genotype 4r than with other genotypes, including other subtypes of genotype 4. Conclusion: The lower rates of sustained virological response in patients infected with subtype 4r are related to the frequent preexistence at treatment baseline and subsequent selection by DAA treatment of both NS5A and NS5B S282 RASs. Our study suggests that these patients should be identified and receive a triple DAA combination regimen as first-line treatment.
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- 2019
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18. Importance of Evaluating Cardiovascular Risk and Hepatic Fibrosis in Patients With Newly Diagnosed Nonalcoholic Fatty Liver Disease
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Alain Sanchez-Rodriguez, Maria Emilia Mendizabal-Rodriguez, Javier Abad, Natalie Madeline Atkinson-Ginsburg, Jonathan Salazar-Segovia, Kassandra Oliva, Ricardo Garcia-Buen Abad, María Cristina Moreno-Del Castillo, Alberto Ríos-Zertuche Caceres, Isaac Ruiz, Jose Ramon Mena-Ramirez, Esteban de Icaza del Río, Joey Piccolo, Jonathan Aguirre-Valadez, and Ignacio García-Juárez
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Adult ,Liver Cirrhosis ,Male ,medicine.medical_specialty ,Cirrhosis ,Disease ,Risk Assessment ,Asymptomatic ,Gastroenterology ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Non-alcoholic Fatty Liver Disease ,Internal medicine ,Nonalcoholic fatty liver disease ,Prevalence ,medicine ,Humans ,Mexico ,Aged ,Cause of death ,Aged, 80 and over ,Hepatology ,business.industry ,Middle Aged ,medicine.disease ,digestive system diseases ,Cardiovascular Diseases ,030220 oncology & carcinogenesis ,Hepatocellular carcinoma ,Female ,030211 gastroenterology & hepatology ,Metabolic syndrome ,medicine.symptom ,Hepatic fibrosis ,business - Abstract
Nonalcoholic fatty liver disease (NAFLD) is a well-recognized health problem, with an estimated worldwide prevalence of 25%.1 It is associated with metabolic syndrome (MetSx) and complications such as cirrhosis and hepatocellular carcinoma. However, the main cause of death in patients with NAFLD is derived from cardiovascular disease, and outcome seems to be determined by the degree of hepatic fibrosis.2 The prevalence of NAFLD and associated cardiovascular risk factors in asymptomatic patients in Mexico are poorly documented, despite having one of the highest rates of obesity and metabolic syndrome worldwide.3.
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- 2019
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19. Beneficial Effect of Tacrolimus… Cyclosporin A, Still up for Discussion!
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Isaac Ruiz
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2019-20 coronavirus outbreak ,Hepatology ,Coronavirus disease 2019 (COVID-19) ,business.industry ,medicine.medical_treatment ,Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) ,Gastroenterology ,Liver transplantation ,Virology ,Tacrolimus ,Calcineurin ,Cyclosporin a ,Correspondence ,medicine ,business - Published
- 2021
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20. Cirrhosis etiology trends in developing countries: Transition from infectious to metabolic conditions. Report from a multicentric cohort in central Mexico
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Alex Gonzalez-Chagolla, Antonio Olivas-Martinez, Jesus Ruiz-Manriquez, Maximiliano Servín-Rojas, Eric Kauffman-Ortega, Luis Carlos Chávez-García, Oscar Juárez-León, Jacqueline Cordova-Gallardo, Juan Daniel Díaz-García, Maria Sarai Gonzalez-Huezo, Guadalupe Milanés-Lizarraga, Victor M Paez-Zayas, Mauricio Castillo-Barradas, Orestes de Jesús Cobos-Quevedo, Francisco Isaí García-Juárez, José Alberto Romero-Lozanía, Liz Toapanta-Yanchapaxi, Juan Francisco Sánchez-Avila, José Alonso Avila-Rojo, Aliberth Bonilla-Salas, Michelle Dirthurbide-Hernández, Isaac Ruiz, Ana K. Valenzuela-Vidales, and Ignacio García-Juárez
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Hepatitis C Virus ,Liver transplantation ,Cirrhosis ,Hepatocellular carcinoma ,MAFLD ,Public aspects of medicine ,RA1-1270 ,Alcohol liver disease - Abstract
Summary: Background: Cirrhosis is a public health threat associated with high mortality. Alcoholic Liver Disease (ALD) is the leading cause in Latin America and Metabolic Associated Fatty Liver Disease (MAFLD) in western countries. In Mexico, ALD and chronic Hepatitis C Virus infection (HCV) were the most frequent aetiologies during the past decades. We aimed to describe the trends in the aetiologies of cirrhosis in a middle-income country. Methods: We performed a retrospective cohort study including patients diagnosed with cirrhosis between 2000 and 2019 from six different tertiary care hospitals in central Mexico. We collected information regarding cirrhosis etiology, year of diagnosis, hepatocellular carcinoma development, liver transplantation, and death. We illustrated the change in the tendencies of cirrhosis aetiologies by displaying the proportional incidence of each etiology over time stratified by age and gender, and we compared these proportions over time using chi square tests. Findings: Overall, 4,584 patients were included. In 2019, MAFLD was the most frequent cirrhosis etiology (30%), followed by ALD (24%) and HCV (23%). During the study period, MAFLD became the leading etiology, ALD remained second, and HCV passed from first to fourth. When analysed by gender, ALD was the leading etiology for men and MAFLD for women. The annual incidence of HCC was 3·84 cases/100 persons-year, the median survival after diagnosis was 12·1 years, and seven percent underwent LT. Interpretation: Increased alcohol consumption and the obesity epidemic have caused a transition in the aetiologies of cirrhosis in Mexico. Public health policies must be tailored accordingly to mitigate the burden of alcohol and metabolic conditions in developing countries. Funding: None.
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- 2022
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21. Interleukins‐17 and 27 promote liver regeneration by sequentially inducing progenitor cell expansion and differentiation
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Bin Gao, Isaac Ruiz, Arthur Brouillet, Adrien Guillot, Fouad Lafdil, Imène Gasmi, Julien Calderaro, Yeni Ait-Ahmed, Sophie Lotersztajn, and Jean-Michel Pawlotsky
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0301 basic medicine ,Cell type ,Hepatology ,Interleukin ,Inflammation ,Original Articles ,Biology ,Liver regeneration ,Cell biology ,Pathogenesis ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,medicine ,Original Article ,030211 gastroenterology & hepatology ,medicine.symptom ,Progenitor cell ,Receptor ,G alpha subunit - Abstract
Liver progenitor cells (LPCs)/ductular reactions (DRs) are associated with inflammation and implicated in the pathogenesis of chronic liver diseases. However, how inflammation regulates LPCs/DRs remains largely unknown. Identification of inflammatory processes that involve LPC activation and expansion represent a key step in understanding the pathogenesis of liver diseases. In the current study, we found that diverse types of chronic liver diseases are associated with elevation of infiltrated interleukin (IL)-17-positive (+) cells and cytokeratin 19 (CK19)+ LPCs, and both cell types colocalized and their numbers positively correlated with each other. The role of IL-17 in the induction of LPCs was examined in a mouse model fed a choline-deficient and ethionine-supplemented (CDE) diet. Feeding of wild-type mice with the CDE diet markedly elevated CK19+Ki67+ proliferating LPCs and hepatic inflammation. Disruption of the IL-17 gene or IL-27 receptor, alpha subunit (WSX-1) gene abolished CDE diet-induced LPC expansion and inflammation. In vitro treatment with IL-17 promoted proliferation of bipotential murine oval liver cells (a liver progenitor cell line) and markedly up-regulated IL-27 expression in macrophages. Treatment with IL-27 favored the differentiation of bipotential murine oval liver cells and freshly isolated LPCs into hepatocytes. Conclusion: The current data provide evidence for a collaborative role between IL-17 and IL-27 in promoting LPC expansion and differentiation, respectively, thereby contributing to liver regeneration. (Hepatology Communications 2018;2:329-343).
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- 2018
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22. 'You want to be fooled': Exploring Semiotics, Polysemy, and Strategic Ambiguity in Christopher Nolan Films
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Isaac Ruiz
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Film semiotics ,media_common.quotation_subject ,Philosophy ,Semiotics ,Ambiguity ,Polysemy ,Linguistics ,media_common - Published
- 2019
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23. Depleted Graphene-Oxide-Semiconductor Junctions for High Energy Radiation Detection
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Gyorgy Vizkelethy, Stephen W. Howell, Paul Thelen, Joshua Shank, Isaac Ruiz, Michael Goldflam, and Thomas E. Beechem
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Materials science ,Silicon ,Graphene ,business.industry ,chemistry.chemical_element ,Electron ,Substrate (electronics) ,Radiation ,law.invention ,Semiconductor ,chemistry ,Depletion region ,law ,Optoelectronics ,business ,Visible spectrum - Abstract
The deeply depleted graphene-oxide-semiconductor junction $(\mathrm{D}^{2}\mathrm{GOS})$ architecture has been shown to be a highly sensitive light detector [1]. In this architecture, photogenerated charge in the depletion region of the semiconductor is separated and then directly readout by an adjacent graphene layer similarly to a photoFET. Although detection of (electrons and light) radiation using graphene has been previously demonstrated, only limited work has been conducted on other types of ionizing radiation detection with graphene [2]–[3]. In this work we demonstrate advances made in high energy (2 & 20 MeV), heavy ion (Si+) detection using the $\mathrm{D}^{2}\mathrm{GOS}$ junction, leveraging our previous experience and fabrication improvements for visible light detection using a silicon absorber substrate.
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- 2019
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24. Sofosbuvir-Daclatasvir-Simeprevir Plus Ribavirin in Direct-Acting Antiviral–Experienced Patients With Hepatitis C
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Giovanna Scoazec, Isaac Ruiz, Alexandre Soulier, Ariane Mallat, Anne Varaut, Murielle François, Françoise Roudot-Thoraval, Christophe Hézode, Slim Fourati, Stéphane Chevaliez, and Jean-Michel Pawlotsky
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0301 basic medicine ,Microbiology (medical) ,Simeprevir ,medicine.medical_specialty ,Daclatasvir ,Sofosbuvir ,business.industry ,Ribavirin ,030106 microbiology ,Hepatitis C ,medicine.disease ,Gastroenterology ,Virological response ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Infectious Diseases ,chemistry ,Internal medicine ,medicine ,030211 gastroenterology & hepatology ,Adverse effect ,business ,Direct acting ,medicine.drug - Abstract
We assessed the broadly used, off-label combination of sofosbuvir, daclatasvir, simeprevir, and ribavirin in direct-acting antiviral-experienced patients, as recommended in current guidelines despite scarce data. After 24 weeks' treatment, sustained virological response 12 weeks after the end of treatment was achieved in 6 patients (60%). Two cirrhotic patients relapsed and 2 discontinued treatment due to serious adverse events.
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- 2017
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25. Chemical vapor deposition of partially oxidized graphene
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Zafer Mutlu, K. Andre Mkhoyan, Ryan J. Wu, Robert Ionescu, Cengiz S. Ozkan, Sina Shahrezaei, Selcuk Temiz, Isaac Ruiz, and Mihrimah Ozkan
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Materials science ,Graphene ,General Chemical Engineering ,Analytical chemistry ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,Chemical vapor deposition ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,law.invention ,symbols.namesake ,Carbon film ,X-ray photoelectron spectroscopy ,Electron diffraction ,chemistry ,law ,symbols ,Graphite ,0210 nano-technology ,Raman spectroscopy ,Carbon - Abstract
Herein, we report on chemical vapor deposition (CVD) of partially oxidized graphene (POG) films on electropolished polycrystalline copper foils at relatively low temperature under near-atmospheric pressure. The structural, chemical, and electronic properties of the films are studied in detail using several spectroscopic and microscopic techniques. The content of carbon and oxygen in the films is identified by chemical mapping at near-atomic scale. Electron diffraction patterns of the films possess clear diffraction spots with a six-fold pattern that is consistent with the hexagonal lattice. The fine structure of the carbon K-edge signal in STEM-EELS spectra of the films is distinguishable from that of graphene and graphite. The presence of oxygen in the films is further supported by a clear oxygen K-edge. Raman spectroscopy and XPS results provide direct evidence for a lower degree of oxidation. The work function of the films is found to be much higher than that of graphene, using UPS measurements.
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- 2017
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26. Hepatocellular carcinoma: French Intergroup Clinical Practice Guidelines for diagnosis, treatment and follow-up (SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, AFEF, SIAD, SFR/FRI)
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Jean Claude Barbare, Philippe Merle, Thomas Aparicio, Janick Selves, Valérie Boige, Olivier Bouché, Isaac Ruiz, Karim Boudjema, Boris Guiu, Thomas Decaens, Jean-Frédéric Blanc, Antoine Hollebecque, Anne Sophie Baumann, François Dewaele, Gaël S. Roth, Audrey Debaillon-Vesque, Olivier Farges, Barbara Dauvois, Mohamed Bouattour, and Gilles Créhange
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medicine.medical_specialty ,Hepatology ,medicine.diagnostic_test ,business.industry ,General surgery ,medicine.medical_treatment ,Gastroenterology ,Evidence-based medicine ,Milan criteria ,Liver transplantation ,medicine.disease ,Systemic therapy ,digestive system diseases ,03 medical and health sciences ,0302 clinical medicine ,030220 oncology & carcinogenesis ,Hepatocellular carcinoma ,Biopsy ,medicine ,030211 gastroenterology & hepatology ,Liver function ,business ,Pathological - Abstract
Introduction This document is a summary of the French Intergroup guidelines regarding the management of hepatocellular carcinoma (HCC) published in March 2019. Method It is a collaborative work under the auspices of most of the French medical societies involved in the management of HCC. It is based on the previous guidelines published in 2017. Recommendations are graded in 3 categories according to the level of evidence of data found in the literature. Results The diagnosis and staging of HCC is essentially based on clinical, biological and imaging features. A pathological analysis obtained by a biopsy of tumoral and non-tumoral liver is recommended. HCCs can be divided into 2 groups, taking into account not only the tumor stage, but also liver function. HCCs accessible to curative treatments are tumors that are in Milan criteria or with an AFP score ≤ 2, mainly treated by surgical resection, local ablation or liver transplantation. Intermediate and advanced HCCs with no liver insufficiency, accessible only to palliative treatments, benefit from TACE, SIRT or systemic therapy according to the presence or absence of macrovascular invasion or extrahepatic spread. Conclusion Such recommendations are in permanent optimization and each individual case must be discussed in a multidisciplinary expert board.
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- 2021
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27. Macrophage autophagy protects against hepatocellular carcinoma by modulation of the hepatic immune microenvironment
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Anthony Deust, Marie-Noële Chobert, Isaac Ruiz, Jean-Michel Pawlotsky, and Fatima Teixeira-Clerc
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Hepatology - Published
- 2020
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28. Monolithically fabricated tunable long-wave infrared detectors based on dynamic graphene metasurfaces
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Clark Kadlec, J.T. Olesberg, Patrick Sean Finnegan, Jin K. Kim, M. B. Sinclair, Stephen W. Howell, Isaac Ruiz, T. R. Fortune, S. D. Hawkins, Thomas E. Beechem, Evan M. Anderson, Joel R. Wendt, Michael Goldflam, Anna Tauke-Pedretti, Eric A. Shaner, Preston T. Webster, John F. Klem, David W. Peters, and W. T. Coon
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010302 applied physics ,Materials science ,Physics and Astronomy (miscellaneous) ,Pixel ,Physics::Instrumentation and Detectors ,Graphene ,business.industry ,Superlattice ,Detector ,Physics::Optics ,Hyperspectral imaging ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,law.invention ,law ,0103 physical sciences ,Transmittance ,Optoelectronics ,Infrared detector ,0210 nano-technology ,business ,Plasmon - Abstract
Here, the design, fabrication, and characterization of an actively tunable long-wave infrared detector, made possible through direct integration of a graphene-enabled metasurface with a conventional type-II superlattice infrared detector, are reported. This structure allows for post-fabrication tuning of the detector spectral response through voltage-induced modification of the carrier density within graphene and, therefore, its plasmonic response. These changes modify the transmittance through the metasurface, which is fabricated monolithically atop the detector, allowing for spectral control of light reaching the detector. Importantly, this structure provides a fabrication-controlled alignment of the metasurface filter to the detector pixel and is entirely solid-state. Using single pixel devices, relative changes in the spectral response exceeding 8% have been realized. These proof-of-concept devices present a path toward solid-state hyperspectral imaging with independent pixel-to-pixel spectral control through a voltage-actuated dynamic response.
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- 2020
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29. Desarrollo de la competencia pragmática en inglés a través de fichas pedagógicas :una propuesta didáctica comunicativa
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JOSUE ISAAC RUIZ LOPEZ and MARIA LUISA TREJO SIRVENT
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Pragmática (Lingüística) [UNAMX] ,Competencia comunicativa [UNAMX] ,5701 [cti] ,Inglés - Estudio y enseñanza [UNAMX] ,4 [cti] ,57 [cti] ,570111 [cti] - Abstract
Esta investigación surge a través de mis vivencias y experiencias como estudiante y profesor de inglés como lengua extranjera. Esto debido a que, durante mi aprendizaje de la lengua inglesa, las clases se enfocaban en desarrollar, en la mayoría de ellas, la competencia lingüística; sin tomar en cuenta la competencia pragmática.
- Published
- 2018
30. Reflectance modulation from a metasurface coupled to intersubband transitions in semiconductor quantum wells using quantum tunneling (Conference Presentation)
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Michael B. Sinclair, Joel R. Wendt, Peide D. Ye, Stephen W. Howell, Salvatore Campione, Jinhyun Noh, Igal Brener, M.D. Lange, Michael C. Wanke, Loan Le, Raktim Sarma, Joshua Shank, Isaac Ruiz, and Michael Goldflam
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Electron density ,Materials science ,Condensed Matter::Other ,business.industry ,Doping ,Physics::Optics ,Heterojunction ,Electron ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Dipole ,Optical modulator ,Polariton ,Optoelectronics ,business ,Quantum tunnelling - Abstract
Coupling of metasurfaces to intersubband transitions (ISTs) in semiconductor quantum wells (QWs) has been extensively studied for various applications ranging from generating giant nonlinear optical response to designing tunable metasurfaces for applications such as ultrafast spatial optical modulators and voltage tunable filters. In this work, we experimentally demonstrate a fundamentally new approach of actively controlling the coupling of ISTs in QWs to a metasurface for voltage tuning its optical response. Unlike previous approaches, we use voltage-controlled quantum tunneling to control the carrier concentration in the QWs for turning on/off the ISTs. We design a multi-quantum well structure consisting of four undoped InGaAs wells with AlInAs barriers grown on top of a highly doped InGaAs layer that acts as an electron reservoir. The heterostructure is optimized such that the first IST in all the wells is at 11µm. A complementary gold metasurface with dipole resonances at 11µm is fabricated on top of the QW structure. We designed the heterostructure such that by applying a bias of 1V, the energy bands of all the QWs get aligned simultaneously, leading to the occupation of the ground state of all the QWs via quantum tunneling of the electrons from the electron reservoir. The ISTs which were turned off due to negligible electron density gets turned on at 1V, and this leads to coupling between the ISTs and the dipoles resonances of the metasurface. The voltage induced coupling leads to reflectance modulation which we confirmed experimentally by rapid scan double modulation FTIR measurements.
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- 2018
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31. Voltage tuning of reflectance from a strongly coupled metasurface-semiconductor hybrid structure (Conference Presentation)
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Michael B. Sinclair, Joel R. Wendt, Peide D. Ye, Stephen W. Howell, Jinhyun Noh, Michael Goldflam, Isaac Ruiz, Joshua Shank, Sean W. Smith, Ganapathi S. Subramania, Raktim Sarma, Salvatore Campione, and Igal Brener
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Ionized impurity scattering ,Amplitude modulation ,Materials science ,Semiconductor ,business.industry ,Doping ,Gate dielectric ,Polariton ,Optoelectronics ,Biasing ,business ,Plasmon - Abstract
Metasurfaces have been investigated for various applications ranging from beam steering, focusing, to polarization conversion. Along with passive metasurfaces, significant efforts are also being made to design metasurfaces with tunable optical response. Among various approaches, voltage tuning is of particular interest because it creates the possibility of integration with electronics. In this work, we demonstrate voltage tuning of reflectance from a complementary metasurface strongly coupled to an epsilon-near-zero (ENZ) mode in an ultrathin semiconductor layer. Our approach involves electrically controlling the carrier concentration of the ENZ layer to modulate the polaritonic coupling between the dipole resonances of the metasurface and the ENZ mode for modulating the reflectance of the metasurface. The hybrid structure we fabricate is similar to MOSCAP configuration where the complementary metasurface offers a continuous gold top layer for biasing and positive/negative bias to the metasurface leads to accumulation/depletion of carriers in the ENZ layer beneath it. We optimized our structure by using InGaAs as the ENZ material because of its high mobility and low effective mass. This allowed us to reduce the doping requirement and thereby reduce the ionized impurity scattering as well as the reverse bias required to deplete the ENZ layer. For low leakage and efficient modulation of carrier density, we used Hafnia as the gate dielectric. We further added a reflecting backplane below the ENZ layer to enhance the interaction and by applying bias, we achieved spectral shifts of 500 nm and amplitude modulation of 11% of one of the polariton branches at 14 µm.
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- 2018
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32. Retreatment with sofosbuvir and simeprevir of patients with hepatitis C virus genotype 1 or 4 who previously failed a daclatasvir‐containing regimen
- Author
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Magali Bouvier-Alias, Ariane Mallat, Isaac Ruiz, Françoise Roudot-Thoraval, Alexandre Soulier, Stéphane Chevaliez, Jean-Michel Pawlotsky, Giovanna Scoazec, Anne Varaut, Cyrille Feray, and Christophe Hézode
- Subjects
Male ,0301 basic medicine ,Simeprevir ,medicine.medical_specialty ,Pyrrolidines ,Daclatasvir ,Sustained Virologic Response ,Sofosbuvir ,Hepatitis C virus ,Pilot Projects ,medicine.disease_cause ,Antiviral Agents ,Gastroenterology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Pegylated interferon ,Internal medicine ,medicine ,Humans ,Treatment Failure ,NS5A ,Hepatology ,business.industry ,Ribavirin ,Imidazoles ,Valine ,Hepatitis C, Chronic ,Middle Aged ,Surgery ,030104 developmental biology ,chemistry ,Asunaprevir ,Drug Therapy, Combination ,Female ,030211 gastroenterology & hepatology ,Carbamates ,business ,medicine.drug - Abstract
UNLABELLED Failure to achieve sustained virological response (SVR) with hepatitis C virus (HCV) direct-acting antiviral-based regimens is commonly associated with emergence of resistance-associated variants (RAVs). To avoid cross-resistance, recent guidelines recommend that patients who have failed on nonstructural protein 5A (NS5A) inhibitors should be retreated with sofosbuvir (SOF; NS5B inhibitor) combined with simeprevir (SIM; protease inhibitor [PI]); however, supporting evidence is lacking. This "real-world" study comprised patients who had failed to achieve SVR on previous NS5A-based therapy with daclatasvir (DCV) plus pegylated interferon (Peg-IFN) and ribavirin (RBV), with (n = 3) or without (n = 13) asunaprevir (ASV; PI). All 16 patients were retreated for 12 weeks with SOF plus SIM, without RBV. Antiviral efficacy was evaluated using the primary endpoint of SVR12 (SVR 12 weeks post-treatment); on-treatment response was also assessed. Patients (N = 16; 13 male; mean age: 54 years [range, 43-73]) were chronically infected with HCV genotype (GT) 1 (1a, n = 11; 1b, n = 3) or 4 (n = 2); they had advanced fibrosis or compensated cirrhosis (FibroScan, 9.6-70 kPa; cirrhosis, n = 9); median baseline HCV-RNA level was 1.38 × 10(6) IU/mL. No patient discontinued treatment because of adverse events or virological failure. All patients achieved HCV RNA below lower limit of quantification (
- Published
- 2016
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33. Characterization of the Anti-Hepatitis C Virus Activity of New Nonpeptidic Small-Molecule Cyclophilin Inhibitors with the Potential for Broad Anti- Flaviviridae Activity
- Author
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Slim Fourati, Muriel Gelin, Quentin Nevers, Rozenn Brillet, Camille Baudesson, Patrice Bruscella, Isaac Ruiz, Maxime Chazal, Flora Donati, Nolwenn Jouvenet, Laurent Softic, Jean-François Guichou, Abdelhakim Ahmed-Belkacem, Nazim Ahnou, Jean-Michel Pawlotsky, Institut Mondor de Recherche Biomédicale (IMRB), Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR10-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Centre National de Référence Virus des hépatites B, C et Delta, Institut National de la Transfusion Sanguine [Paris] (INTS)-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Génomique virale et vaccination, Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS), Centre de Biochimie Structurale [Montpellier] (CBS), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de la Santé et de la Recherche Médicale (INSERM), Q.N. received a predoctoral fellowship grant from the French Ministry for Research. I.R. received predoctoral fellowship grants from the National Agency for Research on AIDS and Viral Hepatitis (ANRS) and the Mexican National Council on Science and Technology (CONACYT). This work was partly supported by French Infrastructure for Integrated Structural Biology (FRISBI) grant ANR-10-INBS-05., We are grateful to Nathalie Pardigon (Institut Pasteur, France), Cécile Khou (Institut Pasteur, France), and Justine Basset (Institut Pasteur, France) for their help with WNV and JEV experiments. We are grateful to Charles M. Rice (Rockefeller University, New York, NY, USA), Ralf Bartenschlager (University of Heidelberg, Germany), Jens Bukh (University of Copenhagen, Denmark), and Takaji Wakita (National Institute for Infectious Diseases, Tokyo, Japan) for kindly providing plasmids., ANR-10-INBS-0005,FRISBI,Infrastructure Française pour la Biologie Structurale Intégrée(2010), Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), and Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
0301 basic medicine ,hepatitis C virus ,Hepatitis C virus ,broad-spectrum antiviral activity ,small molecule ,Hepacivirus ,Viral Nonstructural Proteins ,medicine.disease_cause ,Virus Replication ,Virus ,resistance ,03 medical and health sciences ,Flaviviridae ,Cyclophilin A ,Drug Resistance, Viral ,antiviral agents ,medicine ,Humans ,Pharmacology (medical) ,NS5A ,Cyclophilin ,Pharmacology ,Alisporivir ,biology ,cyclophilin inhibitors ,biology.organism_classification ,Virology ,Small molecule ,Hepatitis C ,3. Good health ,030104 developmental biology ,Infectious Diseases ,Amino Acid Substitution ,[SDV.MP.VIR]Life Sciences [q-bio]/Microbiology and Parasitology/Virology ,Cyclosporine - Abstract
Although members of the Flaviviridae display high incidence, morbidity, and mortality rates, the development of specific antiviral drugs for each virus is unlikely. Cyclophilins, a family of host peptidyl-prolyl cis-trans isomerases (PPIases), play a pivotal role in the life cycles of many viruses and therefore represent an attractive target for broad-spectrum antiviral development. We report here the pangenotypic anti-hepatitis C virus (HCV) activity of a small-molecule cyclophilin inhibitor (SMCypI). Mechanistic and modeling studies revealed that the SMCypI bound to cyclophilin A in competition with cyclosporine (CsA), inhibited its PPIase activity, and disrupted the CypA-nonstructural protein 5A (NS5A) interaction. Resistance selection showed that the lead SMCypI hardly selected amino acid substitutions conferring low-level or no resistance in vitro . Interestingly, the SMCypI selected D320E and Y321H substitutions, located in domain II of the NS5A protein. These substitutions were previously associated with low-level resistance to cyclophilin inhibitors such as alisporivir. Finally, the SMCypI inhibited the replication of other members of the Flaviviridae family with higher 50% effective concentrations (EC 50 s) than for HCV. Thus, because of its chemical plasticity and simplicity of synthesis, our new family of SMCypIs represents a promising new class of drugs with the potential for broad-spectrum anti- Flaviviridae activity as well as an invaluable tool to explore the role of cyclophilins in viral life cycles.
- Published
- 2018
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34. Improved functionality of graphene and carbon nanotube hybrid foam architecture by UV-ozone treatment
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Isaac Ruiz, Ilkeun Lee, Wei Wang, Cengiz S. Ozkan, Francisco Zaera, and Mihrimah Ozkan
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Supercapacitor ,Ozone ,Materials science ,Graphene ,chemistry.chemical_element ,Nanotechnology ,Carbon nanotube ,Electrolyte ,Surface energy ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Electrode ,General Materials Science ,Carbon - Abstract
Optimization of the electrode/electrolyte double-layer interface is a key factor for improving electrode performance of aqueous electrolyte based supercapacitors (SCs). Here, we report the improved functionality of carbon materials via a non-invasive, high-throughput, and inexpensive UV generated ozone (UV-ozone) treatment. This process allows precise tuning of the graphene and carbon nanotube hybrid foam (GM) transitionally from ultrahydrophobic to hydrophilic within 60 s. The continuous tuning of surface energy can be controlled by simply varying the UV-ozone exposure time, while the ozone-oxidized carbon nanostructure maintains its integrity. Symmetric SCs based on the UV-ozone treated GM foam demonstrated enhanced rate performance. This technique can be readily applied to other CVD-grown carbonaceous materials by taking advantage of its ease of processing, low cost, scalability, and controllability.
- Published
- 2015
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35. Graphene-Insulator-Semiconductor Junction for Hybrid Photodetection Modalities
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Isaac Ruiz, Stephen W. Howell, Jeffrey B. Martin, Thomas E. Beechem, Richard K. Harrison, Nicholas Martinez, Paul Davids, Michael Goldflam, and Sean W. Smith
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0301 basic medicine ,Materials science ,Silicon ,lcsh:Medicine ,chemistry.chemical_element ,Insulator (electricity) ,02 engineering and technology ,Photodetection ,Article ,law.invention ,03 medical and health sciences ,law ,lcsh:Science ,Multidisciplinary ,business.industry ,Graphene ,lcsh:R ,Detector ,Transistor ,021001 nanoscience & nanotechnology ,030104 developmental biology ,Semiconductor ,chemistry ,Optoelectronics ,lcsh:Q ,0210 nano-technology ,business ,Visible spectrum - Abstract
A sensitive optical detector is presented based on a deeply depleted graphene-insulator-semiconducting (D2GIS) junction, which offers the possibility of simultaneously leveraging the advantages of both charge integration and localized amplification. Direct read-out and built-in amplification are accomplished via photogating of a graphene field-effect transistor (GFET) by carriers generated within a deeply depleted low-doped silicon substrate. Analogous to a depleted metal-oxide-semiconducting junction, photo-generated charge collects in the potential well that forms at the semiconductor/insulator interface and induces charges of opposite polarity within the graphene film modifying its conductivity. This device enables simultaneous photo-induced charge integration with continuous “on detector” readout through use of graphene. The resulting devices exhibit responsivities as high as 2,500 A/W (25,000 S/W) for visible wavelengths and a dynamic range of 30 dB. As both the graphene and device principles are transferrable to arbitrary semiconductor absorbers, D2GIS devices offer a high-performance paradigm for imaging across the electromagnetic spectrum.
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- 2017
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36. Viral kinetics analysis and virological characterization of treatment failures in patients with chronic hepatitis C treated with sofosbuvir and an NS5A inhibitor
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A. Varaut, M. Francois, J. Guedj, Lila Poiteau, Alexandre Soulier, Thi Huyen Tram Nguyen, Stéphane Chevaliez, Jean-Michel Pawlotsky, G. Scoazec, Christophe Hézode, A. Mallat, Isaac Ruiz, Slim Fourati, and F. Roudot-Thoraval
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0301 basic medicine ,Male ,Pyrrolidines ,Sofosbuvir ,Sustained Virologic Response ,Hepacivirus ,Viral Nonstructural Proteins ,Gastroenterology ,Cohort Studies ,chemistry.chemical_compound ,0302 clinical medicine ,Medicine ,Pharmacology (medical) ,Treatment Failure ,Aged, 80 and over ,Standard treatment ,Imidazoles ,virus diseases ,Valine ,Middle Aged ,Viral Load ,Cohort ,030211 gastroenterology & hepatology ,Drug Therapy, Combination ,Female ,Uridine Monophosphate ,medicine.drug ,Ledipasvir ,Adult ,medicine.medical_specialty ,Daclatasvir ,Genotype ,Antiviral Agents ,03 medical and health sciences ,Internal medicine ,Humans ,In patient ,NS5A ,Aged ,Fluorenes ,Hepatology ,business.industry ,Hepatitis C, Chronic ,digestive system diseases ,Clinical trial ,Kinetics ,030104 developmental biology ,chemistry ,Benzimidazoles ,Carbamates ,business - Abstract
BACKGROUND The combination of sofosbuvir (SOF) plus an NS5A inhibitor for 12 weeks is highly efficacious in patients with chronic hepatitis C. As the costs of generic production of sofosbuvir and NS5A inhibitor are rapidly decreasing, the combination of these DAAs will be the standard treatment in most low- to middle-income countries in the future. AIM To identify key predictors of response that can be used to tailor treatment decisions. METHODS A cohort of 216 consecutive patients infected with HCV genotype 1 (1a: n = 57; 1b: n = 77), 2 (n = 4), 3 (n = 33) or 4 (n = 44) were treated with sofosbuvir (SOF) + daclatasvir (n = 176) or SOF + ledipasvir (n = 40) for 12 weeks. The viral kinetics was analysed using the biphasic model and the cure boundary was used to predict time to clear HCV. RESULTS The overall SVR rate was high (94.4%; n = 204), regardless of the time to viral suppression or low-level viraemia at the end of treatment. The model-based predicted HCV RNA levels at the end of treatment could not differentiate patients who did from those who did not achieve SVR. The presence of NS5A resistance-associated substitutions [position 28 (OR = 70.3, P
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- 2017
37. Dual-band tunable graphene-based filter
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Michael Goldflam, Stephen W. Howell, Isaac Ruiz, and Thomas E. Beechem
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Materials science ,business.industry ,Graphene ,Physics::Optics ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,law.invention ,010309 optics ,Filter (video) ,law ,Logic gate ,0103 physical sciences ,Hardware_INTEGRATEDCIRCUITS ,Optoelectronics ,Multi-band device ,0210 nano-technology ,business ,Optical filter ,Graphene nanoribbons ,Plasmon ,Infrared cut-off filter - Abstract
We have demonstrated a scalable dual-band tunable infrared filter based on gating of a continuous graphene layer. The measured and modeled response of the device are in good agreement.
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- 2017
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38. Silicon Oxide Contamination of Graphene Sheets Synthesized on Copper Substrates via Chemical Vapor Deposition
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Cengiz S. Ozkan, Isaac Ruiz, Wei Wang, Mihrimah Ozkan, and Aaron George
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Materials science ,Graphene ,Scanning electron microscope ,Inorganic chemistry ,chemistry.chemical_element ,General Medicine ,Chemical vapor deposition ,Copper ,Silicate ,law.invention ,chemistry.chemical_compound ,symbols.namesake ,chemistry ,Chemical engineering ,law ,symbols ,Silicon oxide ,Raman spectroscopy ,FOIL method - Abstract
Silicate particle formation on Cu foil during the synthesis of graphene by the commonly used thermal chemical vapor deposition inside of a quartz tube was studied and characterized. The formation of these particles was shown to form simultaneously alongside graphene layers. It is argued that the phase transition of quartz at 573 � C allows copper and hydrocarbon to diffuse into the quartz tube, which in turn causes silicate to precipitate onto the copper foil during the CVD process. Scanning electron microscopy was used to image the contamination and its evolution during prolonged growth times, and energy dispersive X-ray spectroscopy is utilized to identify and trace the potential source of the contamination. Raman spectroscopy and mapping was utilized to demonstrate the negative effects the contamination has on the graphene’s quality and uniformity by showing an increase in
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- 2014
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39. Synthesis of Atomically Thin <tex-math>${\bf MoS}_{\bf 2}$</tex-math> Triangles and Hexagrams and Their Electrical Transport Properties
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Mihrimah Ozkan, Wei Wang, Darshana Wickramaratne, Lauro Zavala, Isaac Ruiz, Mahesh R. Neupane, Roger K. Lake, Cengiz S. Ozkan, Zafer Mutlu, Robert Ionescu, Yu Chai, and Zachary Favors
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Electron mobility ,Photoluminescence ,Materials science ,Scanning electron microscope ,Analytical chemistry ,Chemical vapor deposition ,Computer Science Applications ,Molybdenum trioxide ,symbols.namesake ,chemistry.chemical_compound ,chemistry ,Monolayer ,symbols ,Electrical and Electronic Engineering ,Raman spectroscopy ,Molybdenum disulfide - Abstract
Atomically thin molybdenum disulfide (MoS 2 ) triangles and hexagrams were prepared by a two-step growth ambient pressure chemical vapor deposition (APCVD) process. Molybdenum Trioxide (MoO 3 ) nanobelts, a few microns in length and width, were prepared using a hydrothermal technique and utilized as the starting material. High temperature treatment of the MoO 3 nanobelts followed by a rigorous sulfurization via APCVD processing provided different morphologies of MoS 2 monolayers and bilayer (BL) sheets. Triangle and hexagram morphologies were characterized using Raman spectroscopy, photoluminescence (PL) measurements, scanning electron microscopy and atomic force microscopy (AFM). The regrowth step in the CVD process was proven to be ideal in enlarging the grain size. PL and Raman spectroscopy and AFM results confirmed the presence of monolayer and BL regions in the regrowth growth process. Triangle and hexagram domains are observed to be cooperatively nucleating and coalescing together to form large-area layers. Furthermore, the electrical transport properties of the synthesized MoS 2 layers were studied. Electron mobility based on back gated field effect transistors was measured to be approximately 0.02 cm 2 /V. S.
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- 2014
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40. Inch Scale High Throughput Metrology of Graphene and Graphene Oxide
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Isaac Ruiz, Zafer Mutlu, Cengiz S. Ozkan, Dennis Pleskot, Jeffrey Bell, and Mihrimah Ozkan
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chemistry.chemical_compound ,Materials science ,chemistry ,Scale (ratio) ,Graphene ,law ,Oxide ,Nanotechnology ,Throughput (business) ,Metrology ,law.invention - Published
- 2014
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41. Silicon Decorated Cone Shaped Carbon Nanotube Clusters for Lithium Ion Battery Anodes
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Johnny Wang, Cengiz S. Ozkan, Kazi Ahmed, Mihrimah Ozkan, Aaron George, John Butler, Isaac Ruiz, Hamed Hosseini Bay, and Wei Wang
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Amorphous silicon ,Materials science ,Silicon ,Graphene ,chemistry.chemical_element ,Nanotechnology ,General Chemistry ,Carbon nanotube ,Chemical vapor deposition ,Sputter deposition ,Lithium-ion battery ,law.invention ,Biomaterials ,chemistry.chemical_compound ,chemistry ,law ,General Materials Science ,Lithium ,Biotechnology - Abstract
In this work, we report the synthesis of an three-dimensional (3D) cone-shape CNT clusters (CCC) via chemical vapor deposition (CVD) with subsequent inductively coupled plasma (ICP) treatment. An innovative silicon decorated cone-shape CNT clusters (SCCC) is prepared by simply depositing amorphous silicon onto CCC via magnetron sputtering. The seamless connection between silicon decorated CNT cones and graphene facilitates the charge transfer in the system and suggests a binder-free technique of preparing lithium ion battery (LIB) anodes. Lithium ion batteries based on this novel 3D SCCC architecture demonstrates high reversible capacity of 1954 mAh g(-1) and excellent cycling stability (1200 mAh g(-1) capacity with ≈ 100% coulombic efficiency after 230 cycles).
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- 2014
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42. Characteristics and retreatment of HCV DAA failure patients: Real-life experience
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Christophe Hézode, Lila Poiteau, M. Francois, Slim Fourati, A. Varaut, Alexandre Soulier, F. Donati, S. Giovanna, Isaac Ruiz, C. Stephane, A. Mallat, M. Wlassow, and J.-M. Pawlotsky
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Hepatology - Published
- 2018
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43. Proof-of-concept of full-length genome sequencing as diagnostic tool of acute viral hepatitis
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Slim Fourati, Christophe Hézode, Vanessa Demontant, J.-M. Pawlotsky, Frédéric Le Gal, Emmanuel Gordien, C. Stephane, A.L. Bouter, Isaac Ruiz, Christophe Rodriguez, Hélène Regnault, and G. Gricourt
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Hepatology ,Proof of concept ,medicine ,Computational biology ,Biology ,Viral hepatitis ,medicine.disease ,Full length genome - Published
- 2018
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44. Feasibility and Reliability of a Physical Fitness Test Battery in Individuals with Down Syndrome
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Isaac Ruiz-Gavilán, Francisco Javier Alcántara-Cordero, Antonio Manuel Sánchez-López, R. Cabeza-Ruiz, and Universidad de Sevilla. Departamento de Teoría e Historia de la Educación y Pedagogía Social
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Male ,030506 rehabilitation ,Down syndrome ,Health, Toxicology and Mutagenesis ,Physical fitness ,lcsh:Medicine ,Timed Up and Go test ,Factibilidad ,Body Mass Index ,0302 clinical medicine ,Medicine ,Postural Balance ,Psychometry ,Hand Strength ,Middle Aged ,Ejercicio físico ,Test (assessment) ,Cardiorespiratory Fitness ,Time and Motion Studies ,Psicometría ,Female ,Waist Circumference ,0305 other medical science ,Adult ,medicine.medical_specialty ,Waist ,Physical exercise ,Article ,Young Adult ,03 medical and health sciences ,Physical medicine and rehabilitation ,Humans ,Disabled Persons ,Exercise ,Physical Therapy Modalities ,reliability ,business.industry ,lcsh:R ,Public Health, Environmental and Occupational Health ,Reproducibility of Results ,Cardiorespiratory fitness ,Cross-Sectional Studies ,Síndrome de Down ,psychometry ,Exercise Test ,Quality of Life ,physical fitness ,Feasibility Studies ,business ,Body mass index ,030217 neurology & neurosurgery ,feasibility - Abstract
Background: Down syndrome (DS) is a genetic disorder that occurs because of an abnormal division between cells that results in an extra copy of chromosome 21. Some studies show that physical exercise in people with DS increases some cognitive capacities, such as memory, and improves the quality of life. Aim: The main aim of this study was to perform an analysis of the reliability and feasibility of the SAMU-Disability Fitness (DISFIT) battery in adults with DS. Methods: A cross-sectional study with a test&ndash, retest design was performed in a maximum interval of 2 weeks in 37 subjects (11 women and 26 men) aged between 21 and 58 years old with DS. Eight field-based fitness tests were proposed to assess the physical fitness (PF) of adults with DS: Body Mass Index (BMI), Waist Circumference (WC), the Timed Up and Go test (TUG), the Deep Trunk Flexibility test (DTF), the Hand Grip test (HG), the Timed Stand Test (TST), the 30-s Sit-Up (SUP) and the 6-Min Walk Test (6MWT). Results: The intra-class correlation coefficient (ICC) in all the tests was good and high (>, 0.80), except for the 6MWT, whose reliability was fair. Conclusion: The SAMU-DISFIT battery is a reliable and feasible physical fitness battery which has been created with the purpose of establishing tests which measure the four basic components of PF (flexibility, cardiorespiratory fitness, musculoskeletal fitness and motor fitness) in adults with DS.
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- 2019
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45. Hybrid carbon nanotube and graphene nanostructures for lithium ion battery anodes
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Isaac Ruiz, Cengiz S. Ozkan, Shirui Guo, Hamed Hosseini Bay, Wei Wang, Mihrimah Ozkan, and Zachary Favors
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Materials science ,Renewable Energy, Sustainability and the Environment ,Graphene ,chemistry.chemical_element ,Nanotechnology ,Carbon nanotube ,Chemical vapor deposition ,Lithium-ion battery ,Anode ,law.invention ,chemistry ,Potential applications of carbon nanotubes ,law ,Electrode ,General Materials Science ,Lithium ,Electrical and Electronic Engineering - Abstract
We report on an innovative approach to fabricate lithium ion battery anodes based on optimized growth of hybrid carbon nanotube (CNT) and graphene nanostructures directly on copper foil substrates by an ambient pressure chemical vapor deposition process. Seamlessly connected graphene and CNT pillars provide a relatively strong active material-current collector integrity, which facilitates charge transfer in the system. This innovative architecture provides a binder-free technique for preparing electrodes for lithium ion batteries.
- Published
- 2014
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46. Oxygen etching of thick MoS2 films
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Cengiz S. Ozkan, Lauro Zavala, Robert Ionescu, Kazi Ahmed, Mihri Ozkan, Zafer Mutlu, Isaac Ruiz, Andre Mkhoyan, Zachary Favors, Ryan J. Wu, Chueh Liu, Jong Seok Jeong, and Aaron George
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Materials science ,fungi ,technology, industry, and agriculture ,Metals and Alloys ,Mineralogy ,chemistry.chemical_element ,macromolecular substances ,General Chemistry ,Oxygen ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,stomatognathic system ,chemistry ,Etching (microfabrication) ,Materials Chemistry ,Ceramics and Composites ,Basal plane ,Dry etching ,Composite material ,Oxygen annealing - Abstract
Oxygen annealing of thick MoS2 films results in randomly oriented and controllable triangular etched shapes, forming pits with uniform etching angles. These etching morphologies differ across the sample based on the defect sites situated on the basal plane surface, forming numerous features in different bulk sample thicknesses.
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- 2014
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47. Three Dimentional Graphene-CNTs Foam Architectures for Electrochemical Capacitors
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Shirui Guo, Cengiz S. Ozkan, Isaac Ruiz, Mihrimah Ozkan, and Wei Wang
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Capacitor ,Materials science ,law ,Graphene ,Nanotechnology ,Electrochemistry ,law.invention - Abstract
Electrochemical capacitors are promising alternative energy storage systems dueto their relatively fast rate of energy storage and delivery. We describe a simple andscalable method to grow three-dimensional (3D) graphene/multi-wall carbon nanotubes(MWNTs) hybrid nanostructure on industrially used foamed metal foils (nickel foam) viaa one-step ambient pressure chemical vapor deposition (APCVD). The as-growngraphene/MWNTs carbon nanostructure foam demonstrates a homogeneous and denselypacked hierarchical nanostructure and possesses a high surface area which can bepotentially used for the electrodes of energy storage devices such as supercapacitors andbattery. Symmetrical electrochemical double-layer capacitors (EDLCs) ofgraphene/MWNTs nanostructures shows a high specific capacitance of 286 F g-1 whichleads to an energy density of 39.72 Wh kg-1 and a superior power density of up to 154.67kW kg-1. Moreover, the capacitance retention of ~100% after 11000 charge-dischargecycles demonstrates the high stability of the material for electrodes of supercapacitor.These merits enable the innovative 3D hierarchical graphene/MWNTs foam to serve asEDLC electrodes, resulting in energy storage devices with high stability and powerdensity.
- Published
- 2013
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48. Three dimensional few layer graphene and carbon nanotube foam architectures for high fidelity supercapacitors
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Isaac Ruiz, Shirui Guo, Cengiz S. Ozkan, Krassimir N. Bozhilov, Miroslav Penchev, Dong Yan, Wei Wang, and Mihrimah Ozkan
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Supercapacitor ,Materials science ,Renewable Energy, Sustainability and the Environment ,Graphene ,Graphene foam ,Nanotechnology ,Metal foam ,Carbon nanotube ,Capacitance ,Energy storage ,law.invention ,Capacitor ,law ,General Materials Science ,Electrical and Electronic Engineering - Abstract
Supercapacitors are promising alternative energy storage systems due to their relatively fastrate of energy storage and delivery. We describe a simple and scalable method to fabricatethree-dimensional (3D) few-layer graphene/multi-walled carbon nanotube (MWNT) hybridnanostructures on industrial grade metal foam foils (nickel foam) via a one-step ambientpressure chemical vapor deposition (APCVD) process. The as-grown few-layer graphene/MWNTnanocarbon foams are in the form of a homogeneous and densely packed hierarchicalnanostructures and possess a very large surface area of 743 m 2 g 1 . Symmetrical electro-chemical double-layer capacitors (EDLCs) of 3D hybrid hierarchical few-layer graphene/MWNTnanostructures show a high specific capacitance of 286 F g 1 which leads to an energy density of39.72 Wh kg 1 and a superior power density of up to 154.67 kW kg . Moreover, the capacitanceretention of 99.34% after 85000 charge–discharge cycles demonstrates the very high stability ofthe electrode architectures for supercapacitors. These merits enable the innovative 3Dhierarchical few-layer graphene/MWNT foam to serve as high performance EDLC electrodes,resulting in energy storage devices with very high stability and power density.& 2012 Elsevier Ltd. All rights reserved.2211-2855/$-see front matter & 2012 Elsevier Ltd. All rights reserved.http://dx.doi.org/10.1016/j.nanoen.2012.10.001
- Published
- 2013
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49. Liver transplantation in the most severely ill cirrhotic patients: A multicenter study in acute-on-chronic liver failure grade 3
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Sébastien Dharancy, Astrid Herrerro, Gilles Lebuffe, Eleonora De Martin, Philippe Mathurin, Julien Labreuche, Philippe Ichai, Samir Jaber, Teresa Antonini, Isaac Ruiz, Eric Levesque, Didier Samuel, Alain Duhamel, Georges-Philippe Pageaux, Emmanuel Boleslawski, Alexandre Louvet, Faouzi Saliba, Eric Kipnis, Florent Artru, Guillaume Lassailly, José Ursic-Bedoya, Audrey Coilly, Eric Vibert, and Centre Hospitalier Régional Universitaire [Montpellier] (CHRU Montpellier)
- Subjects
Liver Cirrhosis ,Male ,medicine.medical_specialty ,Cirrhosis ,Time Factors ,Critical Care ,[SDV]Life Sciences [q-bio] ,medicine.medical_treatment ,Liver transplantation ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,law ,Intensive care ,Internal medicine ,medicine ,Humans ,Intensive care unit ,Referral and Consultation ,Survival analysis ,Retrospective Studies ,Hepatology ,business.industry ,Organ dysfunction ,Acute-On-Chronic Liver Failure ,Retrospective cohort study ,Middle Aged ,medicine.disease ,Prognosis ,Survival Analysis ,Surgery ,Liver Transplantation ,Multi-organ dysfunction ,Transplantation ,030220 oncology & carcinogenesis ,Case-Control Studies ,030211 gastroenterology & hepatology ,Female ,France ,medicine.symptom ,business - Abstract
International audience; BACKGROUND & AIMS: Liver transplantation (LT) for the most severely ill patients with cirrhosis, with multiple organ dysfunction (accurately assessed by the acute-on-chronic liver failure [ACLF] classification) remains controversial. We aimed to report the results of LT in patients with ACLF grade 3 and to compare these patients to non-transplanted patients with cirrhosis and multiple organ dysfunction as well as to patients transplanted with lower ACLF grade. METHODS: All patients with ACLF-3 transplanted in three liver intensive care units (ICUs) were retrospectively included. Each patient with ACLF-3 was matched to a) non-transplanted patients hospitalized in the ICU with multiple organ dysfunction, or b) control patients transplanted with each of the lower ACLF grades (three groups). RESULTS: Seventy-three patients were included. These severely ill patients were transplanted following management to stabilize their condition with a median of nine days after admission (progression of mean organ failure from 4.03 to 3.67, p=0.009). One-year survival of transplanted patients with ACLF-3 was higher than that of non-transplanted controls: 83.9 vs. 7.9%, p\textless0.0001. This high survival rate was not different from that of matched control patients with no ACLF (90%), ACLF-1 (82.3%) or ACLF-2 (86.2%). However, a higher rate of complications was observed (100 vs. 51.2 vs. 76.5 vs. 74.3%, respectively), with a longer hospital stay. The notion of a "transplantation window" is discussed. CONCLUSIONS: LT strongly influences the survival of patients with cirrhosis and ACLF-3 with a 1-year survival similar to that of patients with a lower grade of ACLF. A rapid decision-making process is needed because of the short "transplantation window" suggesting that patients with ACLF-3 should be rapidly referred to a specific liver ICU. Lay summary: Liver transplantation improves survival of patients with very severe cirrhosis. These patients must be carefully monitored and managed in a specialized unit. The decision to transplant a patient must be quick to avoid a high risk of mortality.
- Published
- 2016
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50. Exploration of Two-Dimensional Materials for Remote Sensing Applications
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Jessica Depoy, Shiyuan Gao, Michael L. Thomas, Isaac Ruiz, James A. Bartz, and Stephen W. Howell
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Computer science ,Remote sensing application ,Remote sensing - Published
- 2016
- Full Text
- View/download PDF
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