51 research outputs found

    Régulation de la synthétase des acides gras par l'insuline et la T3 : mise en évidence de l'action génomique et non génomique de la T3

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    La synthĂ©tase des acides gras (FAS) est une enzyme clef de la lipogenĂšse hĂ©patique responsable de la synthĂšse des acides gras saturĂ©s Ă  longue chaĂźne. Cette enzyme est rĂ©gulĂ©e au niveau transcriptionel par les nutriments et les hormones. Ainsi, le glucose, l'insuline et la T3 augmentent son activitĂ© alors que les acides gras Ă  moyennes chĂźnes (MCFAs), les acides gras poly-insaturĂ©s (PUFAs) et le glucagon la diminuent. Dans des cellules hĂ©patiques, nous avons mis en Ă©vidence que la T3 et l'insuline Ă©taient capables d'activer de façon synergique l'activitĂ© enzymatique et le niveau d'expression des ARNm de la FAS (14 fois). L'analyse du promoteur a permis de dĂ©montrer que cette activation Ă©tait aussi transcriptionnelle. Par la suite l'Ă©lĂ©ment de rĂ©ponse Ă  la T3 (TRE) a Ă©tĂ© localisĂ© dans la rĂ©gion promotrice du gĂšne FAS. Ce TRE fixe un hĂ©tĂ©rodimĂšre TR/RXR en absence d'hormone et cette fixation est augmentĂ©e en prĂ©sence d'insuline et/ou de T3. L'utilisation de H7, un inhibiteur gĂ©nĂ©ral des serines/thrĂ©onines kinases, nous a permis de mettre en Ă©vidence que des mĂ©canismes de phosphorylation sont impliquĂ©s dans la rĂ©gulation transcriptionelle de la FAS par ces deux hormones. En fait, nous avons dĂ©montrĂ© que la voie de signalisation cellulaire PI3-Kinase/\ud ERK1/2-MAPK est impliquĂ©e dans la rĂ©gulation de la FAS par la T3 via le TRE. De plus, nous avons aussi mis en Ă©vidence un effet de l'insuline sur ce TRE qui impliquerait la mĂȘme voie de signalisation ainsi qu'une voie qui pourrait aussi impliquer Akt. Les mĂȘmes effets non gĂ©nomiques de la T3 et de l'insuline sont aussi observĂ©s au niveau d'un TRE consensus de type DR4. En conclusion, nos rĂ©sultats suggĂšrent que la T3 rĂ©gule la transcription par un mĂ©canisme d'action Ă  la fois gĂ©nomique et non gĂ©nomique impliquant la voie PI3-Kinse/MAPK et que l'insuline est aussi capable de cibler ce TRE par des voies de signalisation spĂ©cifiques. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : FAS, T3, Insuline, PI3-Kinase, Erk1/2-MAPK

    Impact of comprehensive geriatric assessment on survival, function, and nutritional status in elderly patients with head and neck cancer: protocol for a multicentre randomised controlled trial (EGeSOR)

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    BACKGROUND: Survival is poorer in elderly patients with head and neck squamous cell carcinomas [HNSCCs] than in younger patients. Possible explanations include a contribution of co-morbidities to mortality, frequent refusal of standard therapy, and the use of suboptimal treatments due to concern about toxicities. The Comprehensive Geriatric Assessment [CGA] is a multidimensional assessment of general health that can help to customise treatment and follow-up plans. The CGA has been proven effective in several health settings but has not been evaluated in randomised studies of patients with cancer. Our aim here was to assess the impact of the CGA on overall survival, function, and nutritional status of elderly patients with HNSCC. METHODS/DESIGN: EGeSOR is an open-label, multicentre, randomised, controlled, parallel-group trial in patients aged 70 years or older and receiving standard care for HNSCC. The intervention includes four components: the CGA conducted by a geriatrician before cancer treatment, participation of the same geriatrician in cancer treatment selection, a standardised geriatric therapeutic intervention designed by the same geriatrician; and geriatric follow-up for 24 months. The primary endpoint, assessed after 6 months, is a composite criterion including death, functional impairment [Activities of Daily Living score decrease ≄2], and weight loss ≄10%. Secondary endpoints include progression-free survival, unscheduled admissions, quality of life, treatment toxicities, costs, and completion of the planned cancer treatment. A centralised online system is used to perform 1:1 randomisation with a minimisation algorithm for centre, age, T and N stages, and tumour site [oral, oropharyngeal, hypopharyngeal, or laryngeal]. The estimated sample size is 704 patients, who are being recruited by 14 centres in 9 French cities. DISCUSSION: EGeSOR is the first randomised trial of the CGA in elderly cancer patients. We expect the CGA to have direct clinical benefits on the management of elderly patients with HNSCC. If this expectation is fulfilled, the trial may lead to modifications of the management model for elderly patients with cancer. TRIAL REGISTRATION: Trial registration: NCT0202506

    Safety and efficacy of protease inhibitors to treat hepatitis C after liver transplantation: A multicenter experience

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    Background & Aims: Protease inhibitors (PI) with peginterferon/ ribavirin have significantly improved SVR rates in HCV G1 patients. Their use to treat HCV recurrence after liver transplantation (LT) is a challenge. Methods: This cohort study included 37 liver transplant recipients (male, 92%, age 57 ± 11 years), treated with boceprevir (n = 18) or telaprevir (n = 19). The indication for therapy was HCV recurrence (fibrosis stage PF2 (n = 31, 83%) or fibrosing cholestatic hepatitis (n = 6, 16%). Results: Eighteen patients were treatment-naive, five were relapsers and fourteen were non-responders to dual therapy after LT. Twenty-two patients received cyclosporine and fifteen tacrolimus. After 12 weeks of PI therapy, a complete virological response was obtained in 89% of patients treated with boceprevir, and 58% with telaprevir (p = 0.06). The end of treatment virological response rate was 72% (13/18) in the boceprevir group and 40% (4/10) in the telaprevir group (p = 0.125). A sustained virological response 12 weeks after treatment discontinuation was observed in 20% (1/5) and 71% (5/7) of patients in the telaprevir and boceprevir groups, respectively (p = 0.24). Treatment was discontinued in sixteen patients (treatment failures (n = 11), adverse events (n = 5)). Infections occurred in ten patients (27%), with three fatal outcomes (8%). The most common adverse effect was anemia (n = 34, 92%), treated with erythropoietin and/ or a ribavirin dose reduction; thirteen patients (35%) received red blood cell transfusions. The cyclosporine dose was reduced by 1.8 ± 1.1-fold and 3.4 ± 1.0-fold with boceprevir and telaprevir, respectively. The tacrolimus dose was reduced by 5.2 ± 1.5-fold with boceprevir and 23.8 ± 18.2-fold with telaprevir. Conclusions: Our results suggest that triple therapy is effective in LT recipients, particularly those experiencing a severe recurrence. The occurrence of anemia and drug-drug interactions, and the risk of infections require close monitoring.

    Sofosbuvir-based antiviral therapy in hepatitis C virus patients with severe renal failure

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    IF 4.470International audienceBackgroundChronic hepatitis C virus (HCV) infection is the most common chronic liver disease in patients with end-stage renal disease (ESRD). Over the last few years, second-generation direct-acting antivirals have been revolutionary in the treatment of hepatitis C, and sofosbuvir (SOF) is the backbone of most modern treatment strategies. Since SOF is eliminated through the kidney, the aim of this multicentre retrospective study was to assess its antiviral efficacy and safety in HCV-infected patients with severe renal failure [including haemodialysis (HD) patients].MethodsFifty patients (36 males, mean age ± standard deviation 60.5 ± 7.5 years) with chronic HCV infection (G1: 28/56%, cirrhosis: 27/54%) and severe renal failure [i.e. MDRD estimated glomerular filtration rate (eGFR) <35 mL/min], including 35 on HD, were enrolled. Antiviral treatment consisted of SOF/ribavirin (RBV) (n = 7), SOF/RBV/pegylated interferon (n = 2), SOF/daclatasvir ± RBV (n = 30) or SOF/simeprevir ± RBV (n = 11) for 12 or 24 weeks. A reduced dose of SOF (400 mg three times a week or 400 mg every other day) was given to all HD patients. Initial dose of RBV (n = 12) ranged from 400 to 4200 mg/week.ResultsOn an intent-to-treat-based analysis, sustained virological response rate was 86% at 12 weeks. During therapy, haemoglobin levels were not significantly modified, but recombinant erythropoietin (rEPO) dose significantly increased in patients treated with RBV. Two patients (4%) required blood transfusion. No patient had treatment discontinuation due to side effects. Dose of RBV was reduced in two patients (16.7%) during antiviral therapy. Dose of SOF was reduced in two non-HD patients because of side effects. In non-HD patients, median eGFR was not significantly modified during treatment.ConclusionsOur results strongly suggest that SOF-based antiviral therapy, with a reduced dose of SOF, is safe and effective for the treatment of HCV patients with ESRD, including HD patients

    Determinants of high-grade anal intraepithelial lesions in HIV-positive men having sex with men

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    International audienceObjective - To assess determinants for histologically proven high-grade anal intraepithelial lesions (hHSIL) in HIV-positive men who have sex with men (MSM), a population at high-risk of HPV-related anal cancer. Design - APACHES is a prospective study of anal HPV and related-lesions in 513 HIV-positive MSM aged at least 35 years in six centres across France. Methods - At baseline, participants underwent high-resolution anoscopy (HRA) with biopsy of suspicious lesions, preceded by anal swabs for liquid-based cytology, p16/Ki67 immunostaining, and HPV DNA. hHSIL diagnosis was established by histopathological review panel consensus, and determinants assessed by logistic regression. Results - Baseline hHSIL prevalence was 10.4% and did not differ significantly by age, sexual behaviour or HIV/immunodeficiency markers. hHSIL prevalence was significantly elevated in participants who smoked (ORadj = 2.6, 95% CI 1.3-5.5) or who, in concurrent anal swabs, had ASCUS/LSIL (3.6, 95% CI 1.4-9.3) or ASC-H/HSIL (22.2, 95% CI 6.8-72.6) cytologic abnormalities, p16/Ki67 dual positivity (3.4, 95% CI 1.5-7.5), or non-HPV16 HR (13.0, 95% CI 1.7-102), but most notably, HPV16 (46.3, 95% CI 6.1-355) infection. Previous diagnosis of low-grade (2.3, 95% CI 1.0-5.4) or high-grade (3.8, 95% CI 1.5-9.9) anal lesion also conveyed higher hHSIL risk. After controlling for patient-specific determinants, there remained significant centre-specific effects, most clearly in higher risk groups (HPV16-positive participants: 31.3% hHSIL in centres A-D versus 5.1% in centres E and F, P < 0.01). Conclusion - Anal cytology and HPV16 infection are potentially useful determinants of hHSIL risk in HIV-positive MSM, but HIV/immunodeficiency-related variables appear not to be. Controlling for patient-specific hHSIL determinants highlights variability in HRA practice across diverse clinical settings and the need for better standardization of this difficult procedure

    Patterns of Hepatitis C Virus Transmission in Human Immunodeficiency Virus (HIV)–infected and HIV-negative Men Who Have Sex With Men

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    Abstract Background Sexually transmitted acute hepatitis C virus (HCV) infections (AHIs) have been mainly described in human immunodeficiency virus (HIV)–infected men who have sex with men (MSM). Cases in HIV-negative MSM are scarce. We describe the epidemic of AHI in HIV-infected and HIV-negative MSM in Lyon, France. Methods All cases of AHI diagnosed in MSM in Lyon University Hospital from 2014 to 2017 were included. AHI incidence was determined in HIV-infected and in preexposure prophylaxis (PrEP)–using MSM. Transmission clusters were identified by construction of phylogenetic trees based on HCV NS5B (genotype 1a/4d) or NS5A (genotype 3a) Sanger sequencing. Results From 2014 to 2017, 108 AHIs (80 first infections, 28 reinfections) were reported in 96 MSM (HIV-infected, 72; HIV-negative, 24). AHI incidence rose from 1.1/100 person-years (95 confidence interval [CI], 0.7–1.7) in 2014 to 2.4/100 person-years (95 CI, 1.1–2.6) in 2017 in HIV-infected MSM (P = .05) and from 0.3/100 person-years (95 CI, 0.06–1.0) in 2016 to 3.4/100 person-years (95 CI, 2.0–5.5) in 2017 in PrEP users (P < .001). Eleven clusters were identified. All clusters included HIV-infected MSM; 6 also included HIV-negative MSM. All clusters started with ≄1 HIV-infected MSM. Risk factor distribution varied among clusters. Conclusions AHI incidence increased in both HIV-infected and HIV-negative MSM. Cluster analysis suggests initial transmission from HIV-infected to HIV-negative MSM through chemsex and traumatic sexual practices, leading to mixed patterns of transmission regardless of HIV status and no overlap with the general population

    Cumulative detection of anal high-grade squamous intraepithelial lesions over two-year follow-up in men who have sex with men living with HIV in France

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    International audienceWe assessed cumulative detection and determinants of anal high-grade squamous intraepithelial lesions (HSIL) in men who have sex with men living with HIV who underwent three visits over two years, with cytology and high-resolution anoscopy (HRA), within the ANRS-EP57-APACHES study. Cumulative HSIL detection was 33% (134/410), of which 48% were detected at baseline. HSIL detection varied considerably by center (13-51%). Strongest HSIL determinants were baseline HPV16 (adjusted odds ratio [aOR] 8.2; 95% confidence interval [95%CI] 3.6-18.9), and p16/Ki67 (aOR 4.6; 95%CI 2.3-9.1). Repeat annual cytology and HRA improved HSIL detection but did not fully compensate between-center heterogeneity

    Microsporidiosis after liver transplantation: A French nationwide retrospective study

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    International audienceBackground: Microsporidiosis has been largely reported in patients with acquired immunodeficiency syndrome, but emerged as a cause of persistent diarrhea in solid organ transplant patients.Methods: Through the French Microsporidiosis Network and the Groupe français de recherche en greffe de foie, we collected all microsporidiosis cases identified in liver transplant patients between 1995 and 2020 in France.Results: We identified 24 liver transplant recipients with microsporidiosis. Sex ratio was balanced and median age was 58.8 (3.5-83.5) years (there were 4 children). Microsporidiosis occurred at a median time of 3.9 (0.1-18.9) years post-transplant. Median duration of diarrhea before diagnosis was 22 days (12-45). Therapeutic care included immunosuppressive therapy changes in 20 patients, as follows: stop cyclosporine or tacrolimus (n = 2), dose reduction of cyclosporine or tacrolimus (n = 12), stop MMF (n = 5), and dose reduction of corticosteroids (n = 1). In addition, 15 patients received specific therapy against microsporidiosis: fumagillin (n = 11) or albendazole (n = 4). Median duration of treatment was 14 days (8-45 days). Finally, 7 patients had immunosuppressive treatment tapering only. Microsporidiosis was complicated by renal failure in 15 patients, requiring dialysis in one case. Two patients had infection relapse. No patient presented proven rejection within the 3 months after microsporidiosis. None of the patients died within the 3 months after microsporidiosis.Conclusions: Microsporidiosis is a very rare infection after liver transplantation but can induce severe dehydration and renal failure. Therefore, it must be systematically sought in any case of persistent diarrhea after first line screening of frequent infectious causes
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