Accurate gravity anomaly interpolation: a case-study in cameroon, central africa

Many treatments in geodesy and geophysics require regularly gridded gravity anomalies. The gridding of gravity data needs interpolation. For the predicted data to be accurate, the smoothest type ofgravity anomaly should be used along with the most indicated prediction method. This paper presents the comparison of various prediction methods applied on different types of gravity anomalies andconsidering the relative geological complexity of the study area. Many algorithms are tested and the suitability of each type of anomaly and each prediction method discussed in a case-study in Cameroon (Central Africa), using a set of 43,000 gravity data points to determine the must accurate prediction technique

Safety and efficacy of oral fexinidazole in children with gambiense human African trypanosomiasis: a multicentre, single-arm, open-label, phase 2-3 trial

BACKGROUND: Fexinidazole has been reported as an effective oral monotherapy against non-severe gambiense human African trypanosomiasis in a recent trial in adults. We aimed to assess the safety and efficacy of fexinidazole in children across all disease stages of gambiense human African trypanosomiasis. METHODS: We did a multicentre, single-arm, open-label, phase 2-3 trial at eight district hospitals in the Democratic Republic of the Congo. We recruited children with a Karnofsky score of more than 50, those aged 6 years to younger than 15 years, weighing 20 kg or more, and with confirmed gambiense human African trypanosomiasis (any stage). Children weighing 20 kg or more and less than 35 kg received oral fexinidazole of 1200 mg (two x 600 mg tablets) once per day for 4 days (days 1-4) followed by 600 mg (one x 600 mg tablet) once per day for 6 days (days 5-10). Children weighing 35 kg or more received oral fexinidazole of 1800 mg (three x 600 mg tablets) once per day for 4 days (days 1-4), followed by 1200 mg (two x 600 mg tablets) once per day for 6 days (days 5-10). The primary endpoint was fexinidazole treatment success rate 12 months after end of treatment. A rate greater than 80% was deemed acceptable and a target value of 92% was aimed for. Safety was assessed through routine monitoring. This study is completed and registered with ClinicalTrials.gov, number NCT02184689. FINDINGS: Between May 3, 2014, and Nov 22, 2016, we screened a total of 130 paediatric patients, of whom 125 (96%) received at least one dose of fexinidazole. All 125 patients (69 [55%] patients with stage 1, 19 [15%] with early stage 2, and 37 [30%] with late stage 2 gambiense human African trypanosomiasis) completed the 10-day treatment. Treatment success rate at 12 months was 97.6% (95% CI 93.1-99.5; 122 of 125 patients). The primary endpoint was met and the targeted value of 92% was exceeded. Treatment success at 12 months was elevated across all disease stages: 98.6% (95% CI 92.2-99.9; 68 of 69 patients) in stage 1, 94.7% (74.0-99.9; 18 of 19 patients) in early stage 2, and 97.3% (85.8-99.9; 36 of 37 patients) in late stage 2 gambiense human African trypanosomiasis. No new safety issues were observed beyond those found in adult trials. Overall, 116 (93%) of 125 patients reported 586 treatment-emergent adverse events, mainly mild or moderate. The most frequently reported treatment-emergent adverse events of interest during hospital admission were vomiting (86 [69%] of 125) and headache (41 [33%]). Seven (6%) of 125 patients had severe malaria, which was often accompanied by anaemia that was unrelated to fexinidazole. One patient died following dyspnoea and injury due to traumatic aggression 172 days after end of treatment, which was considered unrelated to fexinidazole or gambiense human African trypanosomiasis. INTERPRETATION: Oral fexinidazole is a safe and effective first-line treatment option across all gambiense human African trypanosomiasis disease stages in paediatric patients. FUNDING: Through the Drugs for Neglected Diseases initiative: the Bill & Melinda Gates Foundation (USA), the Republic and Canton of Geneva (Switzerland), the Dutch Ministry of Foreign Affairs (Netherlands), the Norwegian Agency for Development Cooperation (Norway), the Federal Ministry of Education and Research through KfW (Germany), the Brian Mercer Charitable Trust (UK), and other private foundations and individuals from the human African trypanosomiasis campaign. TRANSLATION: For the French translation of the abstract see Supplementary Materials section

Estimating gravity field and quasi-geoid in Cameroon (CGM20)

In this paper, the computation of the new gravimetric quasi-geoid of Cameroon based on some recent global geopotential models and a detailed Digital Terrain Model (DTM) of the area is presented. Besides gravity data supplied by the Bureau Gravim´etrique International (BGI) new data have been collected by the National Institute of Cartography (NIC) of Cameroon and used in the computation. Three different quasi-geoid models have been obtained based on three different global models, namely GOCE-dir5, EGM2008 and XGM2019e_2159. The wellknown remove-compute-restore technique has been applied and Fast Collocation has been used for estimating the residual quasi-geoid component from gridded gravity data. The comparisons with Global Navigation Satellite System/levelling (GNSS/levelling) data distributed over the Cameroon territory show that some improvements have been obtained either with respect to the global model solutions and to previous local estimates computed in the past

Efficacy and safety of pafuramidine versus pentamidine maleate for treatment of first stage sleeping sickness in a randomized, comparator-controlled, international phase 3 clinical trial

Sleeping sickness (human African trypanosomiasis [HAT]) is a neglected tropical disease with limited treatment options that currently require parenteral administration. In previous studies, orally administered pafuramidine was well tolerated in healthy patients (for up to 21 days) and stage 1 HAT patients (for up to 10 days), and demonstrated efficacy comparable to pentamidine.; This was a Phase 3, multi-center, randomized, open-label, parallel-group, active control study where 273 male and female patients with first stage Trypanosoma brucei gambiense HAT were treated at six sites: one trypanosomiasis reference center in Angola, one hospital in South Sudan, and four hospitals in the Democratic Republic of the Congo between August 2005 and September 2009 to support the registration of pafuramidine for treatment of first stage HAT in collaboration with the United States Food and Drug Administration. Patients were treated with either 100 mg of pafuramidine orally twice a day for 10 days or 4 mg/kg pentamidine intramuscularly once daily for 7 days to assess the efficacy and safety of pafuramidine versus pentamidine. Pregnant and lactating women as well as adolescents were included. The primary efficacy endpoint was the combined rate of clinical and parasitological cure at 12 months. The primary safety outcome was the frequency and severity of adverse events. The study was registered on the International Clinical Trials Registry Platform at www.clinicaltrials.gov with the number ISRCTN85534673.; The overall cure rate at 12 months was 89% in the pafuramidine group and 95% in the pentamidine group; pafuramidine was non-inferior to pentamidine as the upper bound of the 95% confidence interval did not exceed 15%. The safety profile of pafuramidine was superior to pentamidine; however, 3 patients in the pafuramidine group had glomerulonephritis or nephropathy approximately 8 weeks post-treatment. Two of these events were judged as possibly related to pafuramidine. Despite good tolerability observed in preceding studies, the development program for pafuramidine was discontinued due to delayed post-treatment toxicity