1. |
- Kattge, Jens, et al.
(författare)
-
TRY plant trait database - enhanced coverage and open access
- 2020
-
Ingår i: Global Change Biology. - : Wiley-Blackwell. - 1354-1013 .- 1365-2486. ; 26:1, s. 119-188
-
Tidskriftsartikel (refereegranskat)abstract
- Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives.
|
|
2. |
|
|
3. |
|
|
4. |
|
|
5. |
|
|
6. |
|
|
7. |
- Nash, S, et al.
(författare)
-
Combined HIV Adolescent Prevention Study (CHAPS): comparison of HIV pre-exposure prophylaxis regimens for adolescents in sub-Saharan Africa-study protocol for a mixed-methods study including a randomised controlled trial
- 2020
-
Ingår i: Trials. - : Springer Science and Business Media LLC. - 1745-6215. ; 21:1, s. 900-
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundHIV remains a major public health issue, especially in Eastern and Southern Africa. Pre-exposure prophylaxis is highly effective when adhered to, but its effectiveness is limited by cost, user acceptability and uptake. The cost of a non-inferiority phase III trial is likely to be prohibitive, and thus, it is essential to select the best possible drug, dose and schedule in advance. The aim of this study, the Combined HIV Adolescent PrEP and Prevention Study (CHAPS), is to investigate the drug, dose and schedule of pre-exposure prophylaxis (PrEP) required for the protection against HIV and the acceptability of PrEP amongst young people in sub-Saharan Africa, and hence to inform the choice of intervention for future phase III PrEP studies and to improve strategies for PrEP implementation.MethodsWe propose a mixed-methods study amongst young people aged 13–24 years. The first component consists of qualitative research to identify the barriers and motivators towards the uptake of PrEP amongst young people in South Africa, Uganda and Zimbabwe. The second component is a randomised clinical trial (ClinicalTrials.gov NCT03986970, June 2019) using a novel ex vivo HIV challenge method to investigate the optimal PrEP treatment (FTC-TDF vs FTC-TAF), dose and schedule. We will recruit 144 amongst HIV-negative uncircumcised men aged 13–24 years from voluntary male medical circumcision clinics in two sites (South Africa and Uganda) and randomise them into one of nine arms. One group will receive no PrEP prior to surgery; the other arms will receive either FTC-TDF or FTC-TAF, over 1 or 2 days, and with the final dose given either 6 or 20 h prior to surgery. We will conduct an ex vivo HIV challenge on their resected foreskin tissue.DiscussionThis study will provide both qualitative and quantitative results to help decide the optimum drug, dose and schedule for a future phase III trial of PrEP. The study will also provide crucial information on successful strategies for providing PrEP to young people in sub-Saharan Africa.Trial registrationClinicalTrials.govNCT03986970. Registered on 14 June 2019
|
|
8. |
- Bjugård Nyberg, Henrik, 1984-, et al.
(författare)
-
Population Pharmacokinetics and Dosing of Ethionamide in Children with Tuberculosis
- 2020
-
Ingår i: Antimicrobial Agents and Chemotherapy. - : American Society for Microbiology. - 0066-4804 .- 1098-6596. ; 64:3
-
Tidskriftsartikel (refereegranskat)abstract
- Ethionamide has proven efficacy against both drug-susceptible and some drug-resistant strains of Mycobacterium tuberculosis. Limited information on its pharmacokinetics in children is available, and current doses are extrapolated from weight-based adult doses. Pediatric doses based on more robust evidence are expected to improve antituberculosis treatment, especially in small children. In this analysis, ethionamide concentrations in children from 2 observational clinical studies conducted in Cape Town, South Africa, were pooled. All children received ethionamide once daily at a weight-based dose of approximately 20 mg/kg of body weight (range, 10.4 to 25.3 mg/kg) in combination with other first- or second-line antituberculosis medications and with antiretroviral therapy in cases of HIV coinfection. Pharmacokinetic parameters were estimated using nonlinear mixed-effects modeling. The MDR-PK1 study contributed data for 110 children on treatment for multidrug-resistant tuberculosis, while the DATiC study contributed data for 9 children treated for drug-susceptible tuberculosis. The median age of the children in the studies combined was 2.6 years (range, 0.23 to 15 years), and the median weight was 12.5 kg (range, 2.5 to 66 kg). A one-compartment, transit absorption model with first-order elimination best described ethionamide pharmacokinetics in children. Allometric scaling of clearance (typical value, 8.88 liters/h), the volume of distribution (typical value, 21.4 liters), and maturation of clearance and absorption improved the model fit. HIV coinfection decreased the ethionamide bioavailability by 22%, rifampin coadministration increased clearance by 16%, and ethionamide administration by use of a nasogastric tube increased the rate, but the not extent, of absorption. The developed model was used to predict pediatric doses achieving the same drug exposure achieved in 50- to 70-kg adults receiving 750-mg once-daily dosing. Based on model predictions, we recommend a weight-banded pediatric dosing scheme using scored 125-mg tablets.
|
|
9. |
- Gafar, Fajri, et al.
(författare)
-
Global estimates and determinants of antituberculosis drug pharmacokinetics in children and adolescents : a systematic review and individual patient data meta-analysis
- 2023
-
Ingår i: European Respiratory Journal. - : European Respiratory Society. - 0903-1936 .- 1399-3003. ; 61:3
-
Forskningsöversikt (refereegranskat)abstract
- Background Suboptimal exposure to antituberculosis (anti-TB) drugs has been associated with unfavourable treatment outcomes. We aimed to investigate estimates and determinants of first-line anti-TB drug pharmacokinetics in children and adolescents at a global level.Methods We systematically searched MEDLINE, Embase and Web of Science (1990–2021) for pharmacokinetic studies of first-line anti-TB drugs in children and adolescents. Individual patient data were obtained from authors of eligible studies. Summary estimates of total/extrapolated area under the plasma concentration–time curve from 0 to 24 h post-dose (AUC0–24) and peak plasma concentration (Cmax) were assessed with random-effects models, normalised with current World Health Organization-recommended paediatric doses. Determinants of AUC0–24 and Cmax were assessed with linear mixed-effects models.Results Of 55 eligible studies, individual patient data were available for 39 (71%), including 1628 participants from 12 countries. Geometric means of steady-state AUC0–24 were summarised for isoniazid (18.7 (95% CI 15.5–22.6) h·mg·L−1), rifampicin (34.4 (95% CI 29.4–40.3) h·mg·L−1), pyrazinamide (375.0 (95% CI 339.9–413.7) h·mg·L−1) and ethambutol (8.0 (95% CI 6.4–10.0) h·mg·L−1). Our multivariate models indicated that younger age (especially <2 years) and HIV-positive status were associated with lower AUC0–24 for all first-line anti-TB drugs, while severe malnutrition was associated with lower AUC0–24 for isoniazid and pyrazinamide. N-acetyltransferase 2 rapid acetylators had lower isoniazid AUC0–24 and slow acetylators had higher isoniazid AUC0–24 than intermediate acetylators. Determinants of Cmax were generally similar to those for AUC0–24.Conclusions This study provides the most comprehensive estimates of plasma exposures to first-line anti-TB drugs in children and adolescents. Key determinants of drug exposures were identified. These may be relevant for population-specific dose adjustment or individualised therapeutic drug monitoring.
|
|
10. |
|
|