Pharmacokinetics of prednisolone in children: an open-label, randomised, two-treatment cross-over trial investigating the bioequivalence of different prednisolone formulations in children with airway disease

Introduction: One in three Danish children under 3 years of age experience asthma-like symptoms, and one-third will later be diagnosed with asthma. Oral prednisolone is used in various formulations to treat acute asthma. However, the potential differences in bioequivalence between these formulations have never been examined in children despite interchangeable use in clinical practice. Methods and analysis: An open-label, randomised, two-treatment cross-over trial investigating the bioequivalence of different prednisolone formulations in children with airway disease. The included patients (6 months-11 years of age) are admitted to the Department of Paediatric and Adolescent Medicine Nordsjællands University Hospital, Hillerød, with asthma or asthma-like symptoms. The primary objective is to assess the bioequivalence between different prednisolone formulations herein area under the concentration time curve, Cmax and Tmax using saliva samples. The secondary objectives are to evaluate tolerability (five-point face scale), adverse events and severity of the disease. If the patient has an intravenous access for other purposes, the saliva samples will be validated with plasma samples. A total of 66 evaluable patients are needed according to European Medicines Agency Guideline on bioequivalence. Ethics and dissemination: Traditional pharmacokinetic trials are burdensome due to the extent of blood samples necessary to capture the time-dependant drug profile. Saliva sampling is far more acceptable for paediatric patients. In addition, this trial adheres to standard dosing strategies. No additional venepunctures are performed, and no additional prednisolone doses are administered. Guidelines for paediatric bioequivalence trials are warranted

Co-existence challenges in small-scale farming when farmers share and save seeds

Gene flow by means of pollen and seeds in maize influences local, regional and global maize biodiversity. Developing countries are centers of diversity for maize and preserve seeds also in informal seed systems. Particularly in poor communities, seed saving and sharing often co-occur with farming on small fields. We present preliminary investigations from a small-scale maize farming community, in Chongwe, Zambia, to illustrate the significance of seed saving and sharing for patterns of gene flow. The potential introduction of genetically modified (GM) plants brings in new dimensions of challenges for farmers e.g. related to: i) co-existence of GM and non-GM varieties; ii) potential infringement of intellectual property rights; and iii) trans-boundary movement of products to countries that do not accept certain GM products. Small-scale farming is vulnerable to cross-contamination due to limited separation between fields. If transgenes are introduced into small-scale agricultural contexts, uncontrolled diffusion and further spread seems unavoidable. Removal of transgenes as well as the regulatory implications of transgenes would require control of innumerable small informal seed stores kept by farmers

Does Perception of Usefulness of Arthroscopic Simulators Differ with Levels of Experience?

Some commercial simulators are available for training basic arthroscopic skills. However, it is unclear if these simulators allow training for their intended purposes and whether the perception of usefulness relates to level of experience. We addressed the following questions: (1) Do commercial simulators have construct (times to perform tasks) and face validity (realism), and (2) is the perception of usefulness (educational value and user-friendliness) related to level of experience? We evaluated two commercially available virtual reality simulators (Simulators A and B) and recruited 11 and nine novices (no arthroscopies), four and four intermediates (one to 59 arthroscopies), and seven and nine experts (> 60 arthroscopies) to test the devices. To assess construct validity, we recorded the median time per experience group for each of five repetitions of one identical navigation task. To assess face validity, we used a questionnaire to judge up to three simulator characteristic tasks; the questionnaire asked about the realism, perception of educational value, and perception of user-friendliness. We observed partial construct validity for Simulators A and B and considered face validity satisfactory for both simulators for simulating the outer appearance and human joint, but barely satisfactory for the instruments. Simulators A and B had equal educational value according to the participants. User-friendliness was judged better for Simulator B although both were graded satisfactory. The perception of usefulness did not differ with level of experience. Our observations suggest training on either simulator is reasonable preparation for real-life arthroscopy, although there is room for improvement for both simulators. These simulators provide training in surgical skills without compromising patient safet