Abacavir pharmacokinetics in African children living with HIV: A pooled analysis describing the effects of age, malnutrition and common concomitant medications

AIMS: Abacavir is part of WHO-recommended regimens to treat HIV in children under 15 years of age. In a pooled analysis across four studies, we describe abacavir population pharmacokinetics to investigate the influence of age, concomitant medications, malnutrition and formulation. METHODS: A total of 230 HIV-infected African children were included, with median (range) age of 2.1 (0.1-12.8) years and weight of 9.8 (2.5-30.0) kg. The population pharmacokinetics of abacavir was described using nonlinear mixed-effects modelling. RESULTS: Abacavir pharmacokinetics was best described by a two-compartment model with first-order elimination, and absorption described by transit compartments. Clearance was predicted around 54% of its mature value at birth and 90% at 10 months. The estimated typical clearance at steady state was 10.7 L/h in a child weighing 9.8 kg co-treated with lopinavir/ritonavir, and was 12% higher in children receiving efavirenz. During co-administration of rifampicin-based antituberculosis treatment and super-boosted lopinavir in a 1:1 ratio with ritonavir, abacavir exposure decreased by 29.4%. Malnourished children living with HIV had higher abacavir exposure initially, but this effect waned with nutritional rehabilitation. An additional 18.4% reduction in clearance after the first abacavir dose was described, suggesting induction of clearance with time on lopinavir/ritonavir-based therapy. Finally, absorption of the fixed dose combination tablet was 24% slower than the abacavir liquid formulation. CONCLUSION: In this pooled analysis we found that children on lopinavir/ritonavir or efavirenz had similar abacavir exposures, while concomitant TB treatment and super-boosted lopinavir gave significantly reduced abacavir concentrations

Towards Regional Scale Stormwater Flood Management Strategies through Rapid Preliminary Intervention Screening

This is the final version. Available on open access from MDPI via the DOI in this recordData Availability Statement: Data underpinning this study is available upon reasonable request through contacting the authors.his paper presents the advantages and opportunities for rapid preliminary intervention screening to enhance inclusion of green infrastructures in regional scale stormwater management. Stormwater flooding is widely recognised as a significant and worsening natural hazard across the globe; however, current management approaches aimed at the site scale do not adequately explore opportunities for integrated management at the regional scale at which decisions are made. This research addresses this gap through supporting the development of stormwater management strategies, including green infrastructure, at a regional scale. This is achieved through upscaling a modelling approach using a spatially explicit inundation model (CADDIES) coupled with an economic model of inundation loss (OpenProFIA) to support widescale evaluation of green infrastructure during the informative early-stage development of stormwater management strategies. This novel regional scale approach is demonstrated across a case study of the San Francisco Bay Area, spanning 8300 sq km. The main opportunity from this regional approach is to identify spatial and temporal trends which are used to inform regional planning and direct future detailed modelling efforts. The study highlights several limitations of the new method, suggesting it should be applied as part of a suite of landscape management approaches; however, highlights that it has the potential to complement existing stormwater management toolkitsNatural Capital ProjectEngineering and Physical Sciences Research Council (EPSRC)Natural Environment Research Council (NERC)Betty and Gordon Moore FoundationNanyang Technological University and National Research Foundation, Prime Minister’s Office, SingaporeEngineering School, Universidad de Buenos Aire

Slab segmentation controls the interplate slip motion in the SW Hellenic subduction: New insight from the 2008Mw 6.8 Methoni interplate earthquake

We present an integrated approach of the seismic structure and activity along the offshore SW Hellenic subduction from combined observations of marine and land seismic stations. Our imaging of the slab top topography from teleseismic receiver function analysis at ocean bottom seismometers supports a trenchward continuation of the along-dip slab faults beneath the Peloponnesus. We further show that their morphostructural control accounts for the backstepping of the thrust contact of the Mediterranean Ridge accretionary wedge over the upper plate. Local seismic activity offshore SW Peloponnesus constrained by ocean bottom seismometer observations reveals a correlation with specific features of the forearc: the Matapan Troughs. We study the Mw6.8 14.02.2008 interplate earthquake offshore SW Peloponnesus and show that its nucleation, rupture zone, and aftershocks sequence are confined to one slab panel between two adjacent along-dip faults and are thus controlled by not only the offshore slab top segmentation but also the upper plate sea-bottom morphology

Optimizing Research to Speed Up Availability of Pediatric Antiretroviral Drugs and Formulations

Globally 1.8 million children are living with human immunodeficiency virus (HIV), yet only 51% of those eligible actually start treatment. Research and development (R&D) for pediatric antiretrovirals (ARVs) is a lengthy process and lags considerably behind drug development in adults. Providing safe, effective, and well-tolerated drugs for children remains critical to ensuring scale-up globally. We review current approaches to R&D for pediatric ARVs and suggest innovations to enable simplified, faster, and more comprehensive strategies to develop optimal formulations. Several approaches could be adopted, including focusing on a limited number of prioritized formulations and strengthening existing partnerships to ensure that pediatric investigation plans are developed early in the drug development process. Simplified and more efficient mechanisms to undertake R&D need to be put in place, and financing mechanisms must be made more sustainable. Lessons learned from HIV should be shared to support progress in developing pediatric formulations for other diseases, including tuberculosis and viral hepatitis

Clinical relevance of nine transcriptional molecular markers for the diagnosis of head and neck squamous cell carcinoma in tissue and saliva rinse

<p>Abstract</p> <p>Background</p> <p>Analysis of 23 published transcriptome studies allowed us to identify nine genes displaying frequent alterations in HNSCC (<it>FN1, MMP1, PLAU, SPARC</it>, <it>IL1RN, KRT4, KRT13, MAL</it>, and <it>TGM3</it>). We aimed to independently confirm these dysregulations and to identify potential relationships with clinical data for diagnostic, staging and prognostic purposes either at the tissue level or in saliva rinse.</p> <p>Methods</p> <p>For a period of two years, we systematically collected tumor tissue, normal matched mucosa and saliva of patients diagnosed with primary untreated HNSCC. Expression levels of the nine genes of interest were measured by RT-qPCR in tumor and healthy matched mucosa from 46 patients. <it>MMP1 </it>expression level was measured by RT-qPCR in the salivary rinse of 51 HNSCC patients and 18 control cases.</p> <p>Results</p> <p>Dysregulation of the nine genes was confirmed by the Wilcoxon test. <it>IL1RN, MAL </it>and <it>MMP1 </it>were the most efficient diagnostic markers of HNSCC, with ROC AUC > 0.95 and both sensitivity and specificity above 91%. No clinically relevant correlation was found between gene expression level in tumor and T stage, N stage, tumor grade, global survival or disease-free survival. Our preliminary results suggests that with 100% specificity, <it>MMP1 </it>detection in saliva rinse is potentially useful for non invasive diagnosis of HNSCC of the oral cavity or oropharynx, but technical improvement is needed since sensitivity was only 20%.</p> <p>Conclusion</p> <p><it>IL1RN, MAL </it>and <it>MMP1 </it>are prospective tumor diagnostic markers for HNSCC. <it>MMP1 </it>overexpression is the most promising marker, and its detection could help identify tumor cells in tissue or saliva.</p

AIDS-defining events and deaths in HIV-infected children and adolescents on antiretrovirals: a 14-year study in Thailand

BACKGROUND: Data are scarce on the long-term clinical outcomes of perinatally HIV-infected children and adolescents receiving antiretroviral therapy (ART) in low/middle-income countries. We assessed the incidence of mortality before (early) and after (late) 6-month of ART and of the composite outcome of new/recurrent AIDS-defining-event or death >6 months after ART start (late AIDS/death) and their associated factors. METHODS: Study population was perinatally HIV-infected children (≤18 years) initiating ART within the Program for HIV Prevention and Treatment observational cohort (NCT00433030). Factors associated with late AIDS/death were assessed using competing risk regression models accounting for loss-to-follow-up, and included baseline and time-updated variables. RESULTS: Among 619 children, "early" mortality incidence was 99 deaths per 1000-PYFU (95%CI; 69-142) and "late" mortality 6 per 1000-PYFU (95%CI; 4-9). Of the 553 children alive >6 months after ART initiation, median age at ART initiation was 6.4 years, CD4% 8.2% and HIV-RNA 5.1 log10 copies/mL. 38 (7%) children developed late AIDS/death after median time of 3.3 years: 24 died and 24 experienced new/recurrent AIDS-defining-events (10 subsequently died). Factors independently associated with late AIDS/death were: current age ≥13 years (adjusted sub-distribution hazard-ratio 4.9; 95%CI; 2.4-10.1), HIV-RNA always ≥400 copies/mL (12.3; 4.0-37.6), BMI-z-score always <-2 SD (13.7; 3.4-55.7), and hemoglobin <8g/dL at least once (4.6; 2.0-10.5). CONCLUSIONS: After the initial 6 months of ART, being an adolescent, persistent viremia, poor nutritional status and severe anemia were associated with poor clinical outcomes. This supports the need for novel interventions that target children, particularly adolescents with poor growth and uncontrolled viremia