Experience and Challenges from Clinical Trials with Malaria Vaccines in Africa.

Malaria vaccines are considered amongst the most important modalities for potential elimination of malaria disease and transmission. Research and development in this field has been an area of intense effort by many groups over the last few decades. Despite this, there is currently no licensed malaria vaccine. Researchers, clinical trialists and vaccine developers have been working on many approached to make malaria vaccine available.African research institutions have developed and demonstrated a great capacity to undertake clinical trials in accordance to the International Conference on Harmonization-Good Clinical Practice (ICH-GCP) standards in the last decade; particularly in the field of malaria vaccines and anti-malarial drugs. This capacity is a result of networking among African scientists in collaboration with other partners; this has traversed both clinical trials and malaria control programmes as part of the Global Malaria Action Plan (GMAP). GMAP outlined and support global strategies toward the elimination and eradication of malaria in many areas, translating in reduction in public health burden, especially for African children. In the sub-Saharan region the capacity to undertake more clinical trials remains small in comparison to the actual need.However, sustainability of the already developed capacity is essential and crucial for the evaluation of different interventions and diagnostic tools/strategies for other diseases like TB, HIV, neglected tropical diseases and non-communicable diseases. There is urgent need for innovative mechanisms for the sustainability and expansion of the capacity in clinical trials in sub-Saharan Africa as the catalyst for health improvement and maintained

Influence of nanodispersed hydrotalcite on polypropylene photooxidation

Nanocomposites containing hydrotalcite and prepared by melt compounding with poly- propylene were UV-light irradiated in artificial accelerated conditions representative of solar irradiation (k > 300 nm) at 60 °C in air. The chemical modifications resulting from photooxidation were followed by IR and UV–visible spectroscopies. The presence of hydrotalcite was shown to change the global rate of photooxidation of polypropylene by reducing the oxidation induction time and increasing the oxidation rate. The differences of the oxidation induction time disappeared after solvent extraction of the antioxidant. They were attributed to a quenching of the antioxidant activity resulting from a migration onto the filler surface induced by the preferential interaction with the polar hydrotalcite. Extracting the antioxidant did not change the oxidation rate at the permanent regime. The increase of the oxidation rate was attributed to transition metal ions, present as impurities in hydrotalcite, which can accelerate the oxidation of the polymer by various mechanisms including a catalysed decomposition of hydroperoxides

Photochemical stabilization of LLDPE/clay nanocomposites: towards durable nanocomposites

This article reports a study of the chemical modifications of LLDPE/nanoblend nanocomposites exposed to UV light in conditions of artificially accelerated ageing and natural weathering. Analysis by infrared spectroscopy of the chemical modifications produced by photoageing shows that the presence of an organo-clay leads to the decrease of the oxidation induction time of the polymer (LLDPE), which results in lower durability of the nanocomposites. Protection against photooxidation was tested with different kinds of UV stabilizers and with a metal deactivator. It is shown that the metal deactivator is very efficient in stabilizing the nanocomposite since it totally cancels the prodegradant effect of the organo-clay. This confirms the role played by iron impurities in natural clays. The use of a metal deactivator offers a new insight into the stabilization strategy for nanocomposites

Persistent use of Analgesic Medications in Mild-to-Moderate Alzheimer's Disease.: Persistent analgesic use in Alzheimer's disease

International audienceBACKGROUND AND OBJECTIVES: Previous studies have reported a lower use of analgesics in patients with Alzheimer's disease (AD) than in non-AD elderly. To date, no study has focused on persistent analgesic use in patients with mild-to-moderate AD. METHODS: The "Réseau sur la maladie d'Alzheimer Français" (REAL.FR) cohort study enrolled community-dwelling patients with mild-to-moderate AD. Persistent analgesic use was defined as the consumption of at least one analgesic drug during two consecutive visits (6 months). Associated factors were identified in a nested case-control study. RESULTS: In REAL.FR, 595 patients were present during at least two consecutive visits [mean age = 77.5 ± 6.8 years, mini-mental state examination (MMSE) = 20.1 ± 4.2]. Prevalence of persistent analgesic use was 13.1 % (95 % CI = 10.4-15.9). The incidence of persistent analgesic use was 5.9/100 patient-years (95 % CI = 5.2-6.6). Women (adjusted odds ratio [OR] = 3.1, 95 % CI = 1.2-8.1), patients with musculoskeletal disorders (OR = 3.4, 95 % CI = 1.6-7.3) and patients treated with numerous medications (OR = 3.0, 95 % CI = 1.5-5.8) were more likely to use analgesics persistently. Statistically significant associations were found with disease duration and disease progression but not with AD severity at baseline. CONCLUSIONS: Our results suggest a low use of analgesics in AD patients, which could vary with AD progression