Analysis of the Geological Controls and Kinematics of the Chgega Landslide (Mateur, Tunisia) Exploiting Photogrammetry and InSAR Technologies

Exploration of territories not previously analyzed by landslide experts provides interesting findings. The Chgega landslide, in northern Tunisia, represents a paradigmatic mass movement. It can be classified as a complex landslide, or more specifically as vast rock spreading that evolved into a block slide. It involves a great block of limestone—about 900 m long and 400 m wide—sliding over ductile clays and marls. The viscoplastic creep of the clays drives the landslide and creates, in its crown, a graben ~800 m long and ~120 m wide that breaks the summit of Chgega Mountain. Using Interferometric Synthetic Aperture Radar (InSAR) technologies, we demonstrate that this complex landslide is currently active and moreover shows progressive movement without clear episodic accelerations. The velocity of the limestone block is just above 2 mm/yr. The occurrence of gravity-induced joints indicates that the movement has an orientation towards 333◦ of azimuth on average, conditioned by the landscape around Chgega. These results were obtained through the analysis of a 3D model and a high-resolution orthoimage created from photographs acquired by an Uncrewed Aerial Vehicle (UAV). We may conclude that the landslide movement is determined by normal faults with directions N060◦E and N140–150◦E. This characterization of the Chgega landslide can serve as the basis for future studies about the origin of this slope movement. Furthermore, the data provided here may support the recognition of Chgega as a singular geological point that deserves to be declared a geosite.The work of J.P.G., P.R., J.V.P.-P., J.M.A., and G.B.-R. was supported by the “Ramón y Cajal” Programme (RYC-2017-23335) of the Spanish Ministry of Science, the project “MORPHOMED”-PID2019-107138RB-I00/SRA (State Research Agency/10.13039/501100011033) and the project “RADANDALUS” (P18-RT-3632), and B-RNM-305- UGR1818 of the FEDER/Junta de Andalucía-Consejería de Transformación Económica, Industria, Conocimiento y Universidades. The access to the Geohazard Exploitation Platform (GEP) of the European Space Agency (ESA) was provided by the Early Adopters Programme. The UAV campaign was carried out with the financial support of the company “Falck Group” (Italy). This study was supported by research projects CGL2015-67130-C2-1-R, Erasmus Mundus External Cooperation Window, and by Scientific Cooperation Agreement 0534 between the Office National des Mines (ONM), the Tunis el Manar University, and the Group for Relief and Active Processes Analysis (ARPA) from the University of Granad

Response to Pegylated Interferon in Chronic Hepatitis B, Effect of with and without Precore Mutant Stain: A Multicenter Tunisian Study

Background and Study Aims: To evaluate the effectiveness of pegylated interferon in patients with chronic hepatitis B infection in a real life setting.Patients and Methods: Fifteen hospitals in Tunisia were included in this study. Data from consecutively treated chronic hepatitis B (CHB) patients, who received pegylated interferon, were collected retrospectively. Baseline demographic and clinical data, on-treatment virological and serological responses and adverse events (AE) were recorded. Sustained virologic response (SVR) is defined as an hepatitis B virus (HBV) DNA concentration of less than 2,000 IU/mL six months after the completion of therapy.Results: A total of 351 CHB patients under peg interferon alfa-2a treatment were included in this multicenter, open label, non-interventional study.Thirty five HBeAg positive patients were identified (62% male, 23% advanced fibrosis). Six months after therapy, 24% had viral loads < 2000 IU/mL, 20% achieved HBeAg seroconversion and 5, 7% achieved HBs Ag loss.Three hundreds sixteen HBeAg negative patients were treated (72, 5% male, 24% advanced fibrosis). Six months post-treatment, 14 % had viral loads < 2000 IU/mL and 1, 2% achieved HBs Ag loss.Treatment was well tolerated in 92% of cases and was stopped in 5.2% of patients.In multivariate analysis, predictors of response to pegylated interferon were: age less than 50 years (P=0,04 IC [0,169-0,737]), precore mutant stain infection (p=0,04 IC [0,60-0,69]), a body mass index < 30kg/m2 (P=0,05 IC [0,225-0,320]), and a pre-treatment serum HBV DNA level <20000IU/ml (P=0,03 IC [1,316-2,225]).Conclusion: PEG-IFN therapy in chronic hepatitis B (CHB) is well tolerated and can achieve a good response especially if we select good responders

Variceal Band Ligation in the Prevention of Variceal Bleeding: A Multicenter Trial

Background/Aim: Variceal bleeding is a life-threatening complication of portal hypertension with a high probability of recurrence. Treatment to prevent first bleeding or rebleeding is mandatory. The study has been aimed at investigating the effectiveness of endoscopic band ligation in preventing upper gastrointestinal bleeding in patients with portal hypertension and to establish the clinical outcome of patients. Patients and Methods: We analyzed in a multicenter trial, the efficacy and side effects of endoscopic band ligation for the primary and secondary prophylaxis of esophageal variceal bleeding. We assigned 603 patients with portal hypertension who were hospitalized to receive treatment with endoscopic ligation. Sessions of ligation were repeated every two to three weeks until the varices were eradicated. The primary end point was recurrent bleeding. Results: The median follow-up period was 32 months. A total of 126 patients had recurrent bleeding. All episodes were related to portal hypertension and 79 to recurrent variceal bleeding. There were major complications in 51 patients (30 had bleeding esophageal ulcers). Seventy-eight patients died, 26 deaths were related to variceal bleeding and 1 to bleeding esophageal ulcers. Conclusions: A great improvement in the prevention of variceal bleeding has emerged over the last years. However, further therapeutic options that combine higher efficacy, better tolerance and fewer side effects are needed

Rare predicted loss-of-function variants of type I IFN immunity genes are associated with life-threatening COVID-19

BackgroundWe previously reported that impaired type I IFN activity, due to inborn errors of TLR3- and TLR7-dependent type I interferon (IFN) immunity or to autoantibodies against type I IFN, account for 15-20% of cases of life-threatening COVID-19 in unvaccinated patients. Therefore, the determinants of life-threatening COVID-19 remain to be identified in similar to 80% of cases.MethodsWe report here a genome-wide rare variant burden association analysis in 3269 unvaccinated patients with life-threatening COVID-19, and 1373 unvaccinated SARS-CoV-2-infected individuals without pneumonia. Among the 928 patients tested for autoantibodies against type I IFN, a quarter (234) were positive and were excluded.ResultsNo gene reached genome-wide significance. Under a recessive model, the most significant gene with at-risk variants was TLR7, with an OR of 27.68 (95%CI 1.5-528.7, P=1.1x10(-4)) for biochemically loss-of-function (bLOF) variants. We replicated the enrichment in rare predicted LOF (pLOF) variants at 13 influenza susceptibility loci involved in TLR3-dependent type I IFN immunity (OR=3.70[95%CI 1.3-8.2], P=2.1x10(-4)). This enrichment was further strengthened by (1) adding the recently reported TYK2 and TLR7 COVID-19 loci, particularly under a recessive model (OR=19.65[95%CI 2.1-2635.4], P=3.4x10(-3)), and (2) considering as pLOF branchpoint variants with potentially strong impacts on splicing among the 15 loci (OR=4.40[9%CI 2.3-8.4], P=7.7x10(-8)). Finally, the patients with pLOF/bLOF variants at these 15 loci were significantly younger (mean age [SD]=43.3 [20.3] years) than the other patients (56.0 [17.3] years; P=1.68x10(-5)).ConclusionsRare variants of TLR3- and TLR7-dependent type I IFN immunity genes can underlie life-threatening COVID-19, particularly with recessive inheritance, in patients under 60 years old