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  1. Article ; Online: Bayesian survival analysis for early detection of treatment effects in phase 3 clinical trials

    Lucie Biard / Anne Bergeron / Vincent Lévy / Sylvie Chevret

    Contemporary Clinical Trials Communications, Vol 21, Iss , Pp 100709- (2021)

    2021  

    Abstract: Despite appealing characteristics for the clinical trials setting, Bayesian inference methods remain scarcely used, especially in randomized controlled clinical trials (RCT). This is particularly true when dealing with a survival endpoint, likely due to ... ...

    Abstract Despite appealing characteristics for the clinical trials setting, Bayesian inference methods remain scarcely used, especially in randomized controlled clinical trials (RCT). This is particularly true when dealing with a survival endpoint, likely due to the additional complexities to model specifications. We propose to use Bayesian inference to estimate the treatment effect in this setting, using a proportional hazards (PH) model for right-censored data. Implementation of such an estimation process is illustrated on two working examples from cancer RCTs, the ALLOZITHRO and the CLL7-SA trials, both originally analyzed using a frequentist approach. In these two different settings, we show that Bayesian sequential analyses can provide early insight on treatment effect in RCTs. Relying on posterior distributions and predictive posterior probabilities, we find that Bayesian sequential analyses of the ALLOZITHRO trial, which was terminated early due to an unanticipated deleterious effect of the intervention on survival, allow quantifying early that the treatment effect was opposite to what was expected. Then, incorporating historical data in the sequential analyses of the CLL7-SA trial would have allowed the treatment effect to be closer to the protocol hypothesis. These post-hoc results give grounds to advocate for a wider use of Bayesian approaches in RCTs, including those with right-censored endpoints, as informative decision tools.
    Keywords Bayesian inference ; Censored data ; Historical data ; Clinical trial ; Medicine (General) ; R5-920
    Subject code 310
    Language English
    Publishing date 2021-03-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Identification of the Axis β-Catenin–BTK in the Dynamic Adhesion of Chronic Lymphocytic Leukemia Cells to Their Microenvironment

    Imane Mihoub / Tareck Rharass / Souhaïl Ouriemmi / Antonin Oudar / Laure Aubard / Valérie Gratio / Gregory Lazarian / Jordan Ferreira / Elisabetta Dondi / Florence Cymbalista / Vincent Levy / Fanny Baran-Marszak / Nadine Varin-Blank / Dominique Ledoux / Christine Le Roy / Laura Gardano

    International Journal of Molecular Sciences, Vol 24, Iss 24, p

    2023  Volume 17623

    Abstract: In the microenvironment, cell interactions are established between different cell types to regulate their migration, survival and activation. β-Catenin is a multifunctional protein that stabilizes cell–cell interactions and regulates cell survival ... ...

    Abstract In the microenvironment, cell interactions are established between different cell types to regulate their migration, survival and activation. β-Catenin is a multifunctional protein that stabilizes cell–cell interactions and regulates cell survival through its transcriptional activity. We used chronic lymphocytic leukemia (CLL) cells as a cellular model to study the role of β-catenin in regulating the adhesion of tumor cells to their microenvironment, which is necessary for tumor cell survival and accumulation. When co-cultured with a stromal cell line (HS-5), a fraction of the CLL cells adhere to stromal cells in a dynamic fashion regulated by the different levels of β-catenin expression. In non-adherent cells, β-catenin is stabilized in the cytosol and translocates into the nucleus, increasing the expression of cyclin D1. In adherent cells, the level of cytosolic β-catenin is low but membrane β-catenin helps to stabilize the adhesion of CLL to stromal cells. Indeed, the overexpression of β-catenin enhances the interaction of CLL with HS-5 cells, suggesting that this protein behaves as a regulator of cell adhesion to the stromal component and of the transcriptional regulation of cell survival. Inhibitors that block the stabilization of β-catenin alter this equilibrium and effectively disrupt the support that CLL cells receive from the cross-talk with the stroma.
    Keywords β-catenin ; microenvironment ; CLL ; BTK ; stromal cells ; Biology (General) ; QH301-705.5 ; Chemistry ; QD1-999
    Subject code 570
    Language English
    Publishing date 2023-12-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Cytokines, chemokines and growth factors profile in human aqueous humor in idiopathic uveitis.

    Marie-Hélène Errera / Ana Pratas / Sylvain Fisson / Thomas Manicom / Marouane Boubaya / Neila Sedira / Emmanuel Héron / Lilia Merabet / Alfred Kobal / Vincent Levy / Jean-Michel Warnet / Christine Chaumeil / Françoise Brignole-Baudouin / José-Alain Sahel / Pablo Goldschmidt / Bahram Bodaghi / Coralie Bloch-Queyrat

    PLoS ONE, Vol 17, Iss 1, p e

    2022  Volume 0254972

    Abstract: To investigate which cytokines, chemokines and growth factors are involved in the immunopathogenesis of idiopathic uveitis, and whether cytokine profiles are associated with. Serum and aqueous humor (AH) samples of 75 patients with idiopathic uveitis ... ...

    Abstract To investigate which cytokines, chemokines and growth factors are involved in the immunopathogenesis of idiopathic uveitis, and whether cytokine profiles are associated with. Serum and aqueous humor (AH) samples of 75 patients with idiopathic uveitis were analyzed by multiplex immunoassay. Infectious controls consisted of 16 patients with ocular toxoplasmosis all confirmed by intraocular fluid analyses. Noninfectious controls consisted of 7 patients with Behçet disease related uveitis and 15 patients with sarcoidosis related uveitis. The control group consisted of AH and serum samples from 47 noninflammatory control patients with age-related cataract. In each sample, 27 immune mediators ± IL-21 and IL-23 were measured. In idiopathic uveitis, 13 of the 29 mediators, including most proinflammatory and vascular mediators such as IL-6, IL-8, IL-12, G-CSF, GM-CSF, MCP-1, IP-10, TNF-α and VEGF, were significantly elevated in the aqueous humor when compared to all controls. Moreover, IL-17, IP-10, and IL-21, were significantly elevated in the serum when compared to all controls. We clustered 4 subgroups of idiopathic uveitis using a statistical analysis of hierarchical unsupervised classification, characterized by the order of magnitude of concentrations of intraocular cytokines. The pathogenesis of idiopathic uveitis is characterized by the presence of predominantly proinflammatory cytokines and chemokines and vascular endothelial growth factor with high expression levels as compared to other causes of uveitis. There are indications for obvious Th-1/ IL21-Th17 pathways but also IL9-Th9 and increased IFN-γ-inducing cytokine (IL12) and IFN-γ-inducible CXC chemokine (IP-10). The combined data suggest that immune mediator expression is different among idiopathic uveitis. This study suggests various clusters among the idiopathic uveitis group rather than one specific uveitis entity.
    Keywords Medicine ; R ; Science ; Q
    Subject code 610
    Language English
    Publishing date 2022-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Cytokines, chemokines and growth factors profile in human aqueous humor in idiopathic uveitis

    Marie-Hélène Errera / Ana Pratas / Sylvain Fisson / Thomas Manicom / Marouane Boubaya / Neila Sedira / Emmanuel Héron / Lilia Merabet / Alfred Kobal / Vincent Levy / Jean-Michel Warnet / Christine Chaumeil / Françoise Brignole-Baudouin / José-Alain Sahel / Pablo Goldschmidt / Bahram Bodaghi / Coralie Bloch-Queyrat

    PLoS ONE, Vol 17, Iss

    2022  Volume 1

    Abstract: To investigate which cytokines, chemokines and growth factors are involved in the immunopathogenesis of idiopathic uveitis, and whether cytokine profiles are associated with. Serum and aqueous humor (AH) samples of 75 patients with idiopathic uveitis ... ...

    Abstract To investigate which cytokines, chemokines and growth factors are involved in the immunopathogenesis of idiopathic uveitis, and whether cytokine profiles are associated with. Serum and aqueous humor (AH) samples of 75 patients with idiopathic uveitis were analyzed by multiplex immunoassay. Infectious controls consisted of 16 patients with ocular toxoplasmosis all confirmed by intraocular fluid analyses. Noninfectious controls consisted of 7 patients with Behçet disease related uveitis and 15 patients with sarcoidosis related uveitis. The control group consisted of AH and serum samples from 47 noninflammatory control patients with age-related cataract. In each sample, 27 immune mediators ± IL-21 and IL-23 were measured. In idiopathic uveitis, 13 of the 29 mediators, including most proinflammatory and vascular mediators such as IL-6, IL-8, IL-12, G-CSF, GM-CSF, MCP-1, IP-10, TNF-α and VEGF, were significantly elevated in the aqueous humor when compared to all controls. Moreover, IL-17, IP-10, and IL-21, were significantly elevated in the serum when compared to all controls. We clustered 4 subgroups of idiopathic uveitis using a statistical analysis of hierarchical unsupervised classification, characterized by the order of magnitude of concentrations of intraocular cytokines. The pathogenesis of idiopathic uveitis is characterized by the presence of predominantly proinflammatory cytokines and chemokines and vascular endothelial growth factor with high expression levels as compared to other causes of uveitis. There are indications for obvious Th-1/ IL21-Th17 pathways but also IL9-Th9 and increased IFN-γ-inducing cytokine (IL12) and IFN-γ-inducible CXC chemokine (IP-10). The combined data suggest that immune mediator expression is different among idiopathic uveitis. This study suggests various clusters among the idiopathic uveitis group rather than one specific uveitis entity.
    Keywords Medicine ; R ; Science ; Q
    Subject code 610
    Language English
    Publishing date 2022-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Effect of chemoprevention by low-dose aspirin of new or recurrent colorectal adenomas in patients with Lynch syndrome (AAS-Lynch)

    Adil Soualy / David Deutsch / Mourad Benallaoua / Amal Ait-Omar / Florence Mary / Sabine Helfen / Marouane Boubaya / Vincent Levy / Robert Benamouzig / the AAS-Lynch group

    Trials, Vol 21, Iss 1, Pp 1-

    study protocol for a multicenter, double-blind, placebo-controlled randomized controlled trial

    2020  Volume 8

    Abstract: Abstract Lynch syndrome (LS) is the most common cause of inherited colorectal cancer (CRC) and confers a high lifetime risk of CRC estimated to be up to 60%. Colonoscopy is recommended every 2 years in LS patients above the 20–25-year-old age bracket, ... ...

    Abstract Abstract Lynch syndrome (LS) is the most common cause of inherited colorectal cancer (CRC) and confers a high lifetime risk of CRC estimated to be up to 60%. Colonoscopy is recommended every 2 years in LS patients above the 20–25-year-old age bracket, and every year when colonic neoplasia has been detected. Efficient chemoprevention has the potential to represent a cost-effective intervention in these high-risk patients and could allow a delay in colonoscopy surveillance. Several epidemiological studies have shown that regular use of low dose aspirin is associated with a 20 to 30% reduction in the risk of sporadic colonic adenomas and colorectal cancer regardless of family risk. However, in recent large randomized trials in specific populations, aspirin use showed no protection for colorectal cancer. A prospective randomized CAPP-2 trial evaluated the effect of aspirin use in LS patients. The primary analysis of this trial showed no significant decrease in CRC in LS patients under daily aspirin. However, a preplanned secondary analysis after an extended follow-up showed a significant reduced risk of CRC in the aspirin group in the per-protocol analysis. The real effect and clinical benefit of aspirin are still to be consolidated in this population. The AAS-Lynch trial—a prospective, multicentric, double-blind, placebo-controlled, randomized clinical trial—was designed to investigate if daily aspirin therapy, at a dose of 100 or 300 mg, would decrease the occurrence or recurrence of colorectal adenomas in patients under 75 years of age, compared with placebo. Trial registration ClinicalTrials.gov NCT02813824 . Registered on 27 June 2016. The trial was prospectively registered.
    Keywords Medicine (General) ; R5-920
    Subject code 610
    Language English
    Publishing date 2020-09-01T00:00:00Z
    Publisher BMC
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article: Un cas d'infection pulmonaire à Mycobacterium shimoïdei à Madagascar.

    Auregan, G / Ramaroson, F / Génin, C / Vincent Lévy-Frébault, V

    Bulletin de la Societe de pathologie exotique (1990)

    1997  Volume 90, Issue 2, Page(s) 75–77

    Abstract: In 1980, a 32 years-old Madagascan female developed a pulmonary tuberculosis, bacteriologically confirmed. She cured with right apical cavitary sequellae. In 1989, she presented haemoptysis again. Antituberculous treatment was adopted without ... ...

    Title translation A case of Mycobacterium shimoïdei lung infection in Madagascar.
    Abstract In 1980, a 32 years-old Madagascan female developed a pulmonary tuberculosis, bacteriologically confirmed. She cured with right apical cavitary sequellae. In 1989, she presented haemoptysis again. Antituberculous treatment was adopted without bacteriological confirmation and did not improve clinical symptoms. In 1991 and 1992 cultures from sputa and bronchi aspiration yielded acid-fast bacilli identified as Mycobacterium shimoïdei. M. tuberculosis could not be detected. The patient died during treatment. This case is the fourth one in the literature. Whereas previous cases have been reported in Europe, Australia, Asia, this new case shows M. shimoïdei is also present in Africa.
    MeSH term(s) Adult ; Australia ; Bronchi/microbiology ; Europe ; Fatal Outcome ; Female ; Hemoptysis/diagnosis ; Humans ; Japan ; Madagascar ; Mycobacterium Infections, Nontuberculous/diagnosis ; Nontuberculous Mycobacteria/isolation & purification ; Sputum/microbiology ; Tuberculosis, Pulmonary/diagnosis ; Tuberculosis, Pulmonary/microbiology
    Language French
    Publishing date 1997
    Publishing country France
    Document type Case Reports ; English Abstract ; Journal Article
    ZDB-ID 419158-4
    ISSN 1961-9049 ; 0037-9085
    ISSN (online) 1961-9049
    ISSN 0037-9085
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article: Pulsed field gel electrophoresis of representatives of Mycobacterium tuberculosis and Mycobacterium bovis BCG strains.

    Varnerot, A / Clément, F / Gheorghiu, M / Vincent-Lévy-Frébault, V

    FEMS microbiology letters

    1992  Volume 77, Issue 1-3, Page(s) 155–160

    Abstract: Using field inversion gel electrophoresis (FIGE), different Mycobacterium tuberculosis strains, such as phage prototypes, exhibit different DNA restriction patterns which are easy to compare. Virulent and avirulent variants of M. tuberculosis H37, as ... ...

    Abstract Using field inversion gel electrophoresis (FIGE), different Mycobacterium tuberculosis strains, such as phage prototypes, exhibit different DNA restriction patterns which are easy to compare. Virulent and avirulent variants of M. tuberculosis H37, as well as daughter strains of M. bovis BCG, display characteristic DNA profiles. BCG strains isolated from suppurative adenitis following vaccination of French patients showed patterns identical to the BCG Pasteur strain used for vaccination. These results demonstrate that FIGE of DNA restriction fragments generated by DraI represents a suitable technique for the analysis of mycobacteria at a genomic level. The DraI profiles allow the differentiation and precise identification of the BCG Pasteur, Glaxo, Russian and Japanese strains.
    MeSH term(s) DNA, Bacterial/genetics ; DNA, Bacterial/isolation & purification ; Deoxyribonucleases, Type II Site-Specific ; Electrophoresis, Gel, Pulsed-Field ; Humans ; Mycobacterium bovis/genetics ; Mycobacterium tuberculosis/genetics ; Mycobacterium tuberculosis/isolation & purification ; Mycobacterium tuberculosis/pathogenicity ; Species Specificity ; Tuberculosis/microbiology ; Virulence/genetics
    Chemical Substances DNA, Bacterial ; Deoxyribonucleases, Type II Site-Specific (EC 3.1.21.4) ; TTTAAA -specific type II deoxyribonucleases (EC 3.1.21.4)
    Language English
    Publishing date 1992-11-01
    Publishing country England
    Document type Comparative Study ; Journal Article
    ZDB-ID 752343-9
    ISSN 1574-6968 ; 0378-1097
    ISSN (online) 1574-6968
    ISSN 0378-1097
    DOI 10.1016/0378-1097(92)90148-h
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Evaluation of nonradioactive DNA probes for identification of mycobacteria.

    Lebrun, L / Espinasse, F / Poveda, J D / Vincent-Levy-Frebault, V

    Journal of clinical microbiology

    1992  Volume 30, Issue 9, Page(s) 2476–2478

    Abstract: Commercial chemiluminescent DNA probes (Accuprobe; Gen-Probe, San Diego, Calif.) for the identification of Mycobacterium tuberculosis (MTB) complex, M. avium complex (MAC), M. gordonae, and M. kansasii were evaluated with 134 clinical isolates. These ... ...

    Abstract Commercial chemiluminescent DNA probes (Accuprobe; Gen-Probe, San Diego, Calif.) for the identification of Mycobacterium tuberculosis (MTB) complex, M. avium complex (MAC), M. gordonae, and M. kansasii were evaluated with 134 clinical isolates. These included 36 MTB complex, 40 MAC, 27 M. gordonae, 9 M. kansasii, and 22 Mycobacterium spp. The specificity was 100% for the four probes. The sensitivity was 100% for the MTB complex and M. gordonae probes and 95.2% for the MAC probe. Five of the nine M. kansasii isolates tested were not detected with the probe.
    MeSH term(s) DNA Probes ; Evaluation Studies as Topic ; False Negative Reactions ; Luminescent Measurements ; Mycobacterium/classification ; Mycobacterium/genetics ; Mycobacterium/isolation & purification ; Sensitivity and Specificity
    Chemical Substances DNA Probes
    Language English
    Publishing date 1992-09
    Publishing country United States
    Document type Comparative Study ; Journal Article
    ZDB-ID 390499-4
    ISSN 1098-660X ; 0095-1137
    ISSN (online) 1098-660X
    ISSN 0095-1137
    DOI 10.1128/jcm.30.9.2476-2478.1992
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Restriction fragment length polymorphism analysis using IS6110 as an epidemiological marker in tuberculosis.

    Otal, I / Martín, C / Vincent-Lévy-Frebault, V / Thierry, D / Gicquel, B

    Journal of clinical microbiology

    1991  Volume 29, Issue 6, Page(s) 1252–1254

    Abstract: The mycobacterial insertion sequence IS6110 has been shown to be present in multiple copies in the chromosome of Mycobacterium tuberculosis. IS6110 restriction fragment length polymorphism analysis of strains isolated from patients who developed ... ...

    Abstract The mycobacterial insertion sequence IS6110 has been shown to be present in multiple copies in the chromosome of Mycobacterium tuberculosis. IS6110 restriction fragment length polymorphism analysis of strains isolated from patients who developed tuberculosis showed identical patterns over a 2- to 3-year period. In contrast, a high degree of polymorphism was observed between strains of the M. tuberculosis complex isolated from different patients. This study demonstrates that the presence of IS6110 does not induce in vivo major genomic rearrangements over a 2- to 3-year period and confirms its use as a valuable epidemiological marker in tuberculosis.
    MeSH term(s) Base Sequence ; DNA Transposable Elements ; DNA, Bacterial/genetics ; Genetic Markers ; Humans ; Molecular Sequence Data ; Mycobacterium tuberculosis/genetics ; Mycobacterium tuberculosis/isolation & purification ; Polymorphism, Restriction Fragment Length ; Tuberculosis/epidemiology ; Tuberculosis/microbiology
    Chemical Substances DNA Transposable Elements ; DNA, Bacterial ; Genetic Markers
    Language English
    Publishing date 1991-06
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 390499-4
    ISSN 1098-660X ; 0095-1137
    ISSN (online) 1098-660X
    ISSN 0095-1137
    DOI 10.1128/jcm.29.6.1252-1254.1991
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: The genes coding for the antigen 85 complexes of Mycobacterium tuberculosis and Mycobacterium bovis BCG are members of a gene family: cloning, sequence determination, and genomic organization of the gene coding for antigen 85-C of M. tuberculosis.

    Content, J / de la Cuvellerie, A / De Wit, L / Vincent-Levy-Frébault, V / Ooms, J / De Bruyn, J

    Infection and immunity

    1991  Volume 59, Issue 9, Page(s) 3205–3212

    Abstract: A gene encoding the 33-kDa secreted protein of Mycobacterium tuberculosis (antigen 85-C) was isolated and sequenced. The corresponding DNA sequence contains a 1,020-bp coding region. The deduced amino acid sequence corresponds to a 340-residue protein ... ...

    Abstract A gene encoding the 33-kDa secreted protein of Mycobacterium tuberculosis (antigen 85-C) was isolated and sequenced. The corresponding DNA sequence contains a 1,020-bp coding region. The deduced amino acid sequence corresponds to a 340-residue protein consisting of a 46-amino-acid signal peptide and a 294-amino-acid mature protein. Comparison with previously described genes for the 30-kDa antigen (the alpha antigen of M. bovis BCG, also called antigen 85-B) and the 32-kDa antigens from M. bovis BCG and M. tuberculosis (antigens 85-A) indicates that the three genes share considerable sequence homology (70.8 to 77.5%) but may also code for distinctive epitopes. Strong differences among the three sequences are clearly visible upstream and downstream from the region coding for the mature proteins. The three genes have been detected in the genome of M. bovis BCG by Southern blot hybridization with three type-specific probes. Furthermore, hybridization of large DNA fragments (100 to 1,000 kbp) from M. tuberculosis separated by pulsed-field gel electrophoresis showed that the three genes coding for the antigen 85 complex are not clustered within the bacterial genome.
    MeSH term(s) Amino Acid Sequence ; Antigens, Bacterial/genetics ; Base Sequence ; Blotting, Southern ; DNA, Bacterial/genetics ; Electrophoresis, Polyacrylamide Gel ; Epitopes/immunology ; Molecular Sequence Data ; Mycobacterium bovis/genetics ; Mycobacterium bovis/immunology ; Mycobacterium tuberculosis/genetics ; Mycobacterium tuberculosis/immunology ; Nucleic Acid Hybridization ; Polymerase Chain Reaction ; Protein Sorting Signals/genetics ; Sequence Homology, Nucleic Acid
    Chemical Substances Antigens, Bacterial ; DNA, Bacterial ; Epitopes ; Protein Sorting Signals
    Language English
    Publishing date 1991-09
    Publishing country United States
    Document type Comparative Study ; Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 218698-6
    ISSN 1098-5522 ; 0019-9567
    ISSN (online) 1098-5522
    ISSN 0019-9567
    DOI 10.1128/iai.59.9.3205-3212.1991
    Database MEDical Literature Analysis and Retrieval System OnLINE

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