Small-molecule G-quadruplex stabilizers reveal a novel pathway of autophagy regulation in neurons

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High doses of favipiravir in two men survivors of Ebola virus disease carrying Ebola virus in semen in Guinea

BACKGROUND: Persistence of Ebola virus (EBOV) in semen remains of deep concern, as sexual transmission of EBOV seems plausible up to 6 months after acute phase of Ebola virus disease (EVD). Favipiravir, a broad spectrum antiviral product, has been evaluated in reducing EVD mortality in Guinea in 2014-2015 in the JIKI trial, the pharmacokinetic results of which suggest that an increase of dose might be necessary to achieve a therapeutically relevant exposure. In FORCE trial, we aimed at evaluating the tolerance and activity of high doses of favipiravir in male EVD survivors with EBOV RNA detection in semen in Guinea. CASE: In 2016, we launched a phase IIa open-labeled multicenter dose escalation study. Male survivors of EVD with EBOV RT-PCR positive on semen received a loading dose of 2400 mg BID of favipiravir on day 1 then a maintenance dose of 1800 mg BID from day 2-14. The primary outcome was the tolerance, assessed daily during period treatment and up to day 90. Unfortunately only two participants were included and the trial was stopped for lack of recruitment. No clinical adverse event of grade 3/4 was reported for both patients. One patient experienced a grade 3 hypocalcemia at day 10 and 14. CONCLUSIONS: High doses of favipiravir were well tolerated in these two participants. Better characterized tolerance and pharmacokinetics of high doses of favipiravir are of utmost importance considering that favipiravir is a candidate treatment for a variety of emerging severe viral diseases with poor prognosis

Evaluation by simulation of clinical trial designs for evaluation of treatment during a viral haemorrhagic fever outbreak

International audienceBackground: Viral haemorrhagic fevers are characterized by irregular outbreaks with high mortality rate. Difficulties arise when implementing therapeutic trials in this context. The outbreak duration is hard to predict and can be short compared to delays of trial launch and number of subject needed (NSN) recruitment. Our objectives were to compare, using clinical trial simulation, different trial designs for experimental treatment evaluation in various outbreak scenarios.Methods: Four type of designs were compared: fixed or group-sequential, each being single- or two-arm. The primary outcome was 14-day survival rate. For single-arm designs, results were compared to a pre-trial historical survival rate pH. Treatments efficacy was evaluated by one-sided tests of proportion (fixed designs) and Whitehead triangular tests (group-sequential designs) with type-I-error = 0.025. Both survival rates in the control arm pC and survival rate differences Δ (including 0) varied. Three specific cases were considered: "standard" (fixed pC, reaching NSN for fixed designs and maximum sample size NMax for group-sequential designs); "changing with time" (increased pC over time); "stopping of recruitment" (epidemic ends). We calculated the proportion of simulated trials showing treatment efficacy, with K = 93,639 simulated trials to get a type-I-error PI95% of [0.024;0.026].Results: Under H0 (Δ = 0), for the "standard" case, the type-I-error was maintained regardless of trial designs. For "changing with time" case, when pC > pH, type-I-error was inflated, and when pC < pH it decreased. Wrong conclusions were more often observed for single-arm designs due to an increase of Δ over time. Under H1 (Δ = + 0.2), for the "standard" case, the power was similar between single- and two-arm designs when pC = pH. For "stopping of recruitment" case, single-arm performed better than two-arm designs, and fixed designs reported higher power than group-sequential designs. A web R-Shiny application was developed.Conclusions: At an outbreak beginning, group-sequential two-arm trials should be preferred, as the infected cases number increases allowing to conduct a strong randomized control trial. Group-sequential designs allow early termination of trials in cases of harmful experimental treatment. After the epidemic peak, fixed single-arm design should be preferred, as the cases number decreases but this assumes a high level of confidence on the pre-trial historical survival rate

Regulation of autophagy by DNA G-quadruplexes

International audienceGuanine-rich DNA strands can form secondary structures known as G-quadruplexes (G4-DNA). G4-DNA is important for the regulation of replication and transcription. We recently showed that the expression of Atg7, a gene that is critical for macroautophagy/autophagy, is controlled by G4-DNA in neurons. We demonstrated that the transcription factor SUB1/PC4 and the G4-DNA-specific antibody HF2 bind to a putative G4-DNA motif located in the Atg7 gene. Stabilizing G4-DNA with the G4-ligand pyridostatin (PDS) downregulates Atg7 expression in neurons. Here, we further investigated how G4-DNA in the Atg7 gene is stabilized by PDS. We show that PDS can form 1:1 and 2:1 complexes with the Atg7's G4. We also demonstrate that PDS downregulates the ATG7 protein and the expression of Atg7 in astrocytes as well as in neurons. Together with our previous findings, these data establish a novel G4-DNA-associated mechanism of autophagy regulation at a transcriptional level in neurons and astrocytes

SARS-COV-2 excretion and maternal-fetal transmission: Virological data of French prospective multi-center cohort study COVIPREG during the first wave

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High heart rate at admission as a predictive factor of mortality in hospitalized patients with Lassa fever: An observational cohort study in Sierra Leone

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High-risk exposure without personal protective equipment and infection with SARS-CoV-2 in healthcare workers: results of the CoV-CONTACT prospective cohort

Posté sur Medrxiv le 18 septembre 2020Objective:We aimed to estimate the risk of infection in Healthcare workers (HCWs) following a high-risk exposure without personal protective equipment (PPE). Methods:We conducted a prospective cohort in HCW s who had a high-risk exposure to SARS-CoV-2-infected subject without PPE. Daily symptoms were self-reported for 30 days, nasopharyngeal swabs for SARS-CoV-2 RT-PCR were performed at inclusion and at days 3, 5, 7 and 12, SARS-CoV-2 serology was assessed at inclusion and at day 30. Confirmed infection was defined by positive RT-PCR or seroconversion, and possible infection by one general and one specific symptom for two consecutive days. Results:Between February 5th and May 30th, 2020, 154 HCWs were enrolled within 14 days following one high-risk exposure to either a hospital patient (70/154; 46.1%) and/or a colleague (95/154; 62.5%). At day 30, 2 5.0% had a confirmed infection (37/148; 95% CI, 18.4 %; 32.9%), and 43.9% (65/148; 95%CI, 35.9%; 52.3 %) had a confirmed or possible infection. Factors independently associated with confirmed or possible SARS-CoV-2 infection were being a pharmacist or administrative assistant rather than being from medical staff (adjusted OR (aOR)=3.8, CI95%=1 .3; 11.2, p=0.01) , and exposure to a SARS-CoV-2-inf ected patient rather than exposure to a SARS-CoV-2-infected colleague (a OR=2 .6, CI95%=1.2; 5.9, p=0.02). Among the 26 HCWs with a SARS-CoV-2-positive nasopharyngeal swab, 7 (26.9 %) had no symptom at the time of the RT-PCR positivity. Conclusions:The proportion of HCWs with confirmed or possible SARS-CoV-2 infection was high. There were less occurrences of high-risk exposure with patients than with colleagues, but those were associated with an increased risk of infection

Prospective external validation of a new non‐invasive test for the diagnosis of non‐alcoholic steatohepatitis in patients with type 2 diabetes

International audienceBackgroundOne of the unmet needs in patients with type 2 diabetes mellitus (T2DM) is the prediction of non-alcoholic liver disease by non-invasive blood tests, for each of the three main histological features, fibrosis, non-alcoholic steatohepatitis (NASH) and steatosis.AimsTo validate externally the performances of a recent panel, Nash-FibroTest, for the assessment of the severity of fibrosis stages, NASH grades and steatosis grades.MethodsWe prospectively analysed 272 patients with T2DM. Standard definitions of stages and grades were used, and analyses were centralised and blinded. The performances of the FibroTest, NashTest-2 and SteatoTest-2 were assessed using the Obuchowski measure (OM), the main outcome recommended as a summary measure of accuracy includeing all pairwise stages and grades comparisons, which is not provided par the extensively used binary area under the ROC curve.ResultsThe diagnostic performance of each component of the panel was significant. OM (SE; significance) of the FibroTest, the NashTest-2 and the SteatoTest-2 was 0.862 (0.012; P < 0.001), 0.827 (0.015; P < 0.001) and 0.794 (0.020; P < 0.01), respectively. For ballooning and lobular inflammation, OM was 0.794 (0.021; P < 0.001) and 0.821 (0.017; P < 0.001), respectively. In a post hoc analysis the FibroTest outperformed VCTE by 4.1% (2.5-6.5; P < 0.001) for reliability, with a non-significant difference for OM for fibrosis staging, 0.859 (0.012) for FibroTest vs 0.870 (0.009) for VCTE.ConclusionsFrom a single blood sample, the panel provides non-invasive diagnosis of the stages of fibrosis, and the grades of NASH and steatosis in patients with T2DM

High Prevalence of NASH and Advanced Fibrosis in Type 2 Diabetes: A Prospective Study of 330 Outpatients Undergoing Liver Biopsies for Elevated ALT, Using a Low Threshold

   OBJECTIVE Most people with type 2 diabetes (T2DM) and nonalcoholic steatohepatitis (NASH) or advanced fibrosis remain undiagnosed, resulting in missed opportunities for early intervention. This multicenter prospective study aimed at assessing the yield of using routinely available data for identifying these patients. RESEARCH DESIGN AND METHODS A total of 713 outpatients with T2DM, screened in four diabetology clinics for nonalcoholic fatty liver disease (NAFLD) according to American Diabetes Association criteria, were referred to hepatologists for further work-up (FIB-4 and vibration controlled transient elastography (VCTE)). A liver biopsy was proposed when ALT levels were persistently >20 IU/L in females or >30 IU/L in males, in the absence of other liver disease. RESULTS Liver biopsies were performed in 360 patients and considered adequate for reading after central review in 330 (median age 59 years, male 63%, BMI 32 kg/m2, HbA1C 7.5 %). Prevalence of NASH, advanced fibrosis, and cirrhosis were 58%, 38%, and 10%, respectively. Liver lesions were independently associated with the components of metabolic syndrome, but not with the micro- and macrovascular complications of T2DM. Models based on routinely available data with or without VCTE had good accuracy to predict advanced fibrosis (AUROC 0.84 and 0.77, correctly classified 59% and 45%, respectively) and NASH (AUROC 0.82 and 0.81, 44% and 42%, respectively).  CONCLUSIONS Despite the use of a low ALT threshold, prevalence of NASH (58%) or advanced fibrosis (38%) was high. Routinely available data had a high yield in identifying T2DM patients with advanced fibrosis and/or NASH requiring further liver assessment.</p