Characterization of binary mixtures consisting of cross-linked high amylose starch and hydroxypropylmethylcellulose used in the preparation of controlled release tablets

Cross-linked amylose starch (CLA), hydroxypropylmethylcellulose (HPMC), and HPMC/CLA matrices were prepared by direct compression. HPMC was used to slow down the enzymatic degradation of CLA matrices. CLA was either granulated alone and mixed with HPMC or cogranulated with the latter. Compaction characteristics of the powder, hydration and mechanical properties of the resulting matrices, as well as the release profiles of three model drugs were investigated. The results showed that wet granulation of CLA in the presence of 10% HPMC improved significantly the flow properties of the powder without compromising its compactibility. Both CLA and HPMC deformed mainly by plastic flow (yield pressures are 75 and 124 MPa, respectively), but CLA exhibited a stronger elastic component (elastic recoveries are 18.4 and 11.5%, respectively). The values of yield pressure increased linearly with the concentration of HPMC. The addition of HPMC to CLA slightly decreased the resistance to consolidation but the crushing force of the final compacts was found to be proportional to the HPMC concentration. Mechanical studies on swollen matrices revealed that CLA formed a stronger gel than HPMC or CLA/HPMC mixture, and swelling and erosion of the tablets increased with HPMC content and incubation time. The in vitro release kinetics of three model drugs (pseudeoephedrine sulfate, sodium diclofenac, and prednisone) showed a clear effect of drug solubility and presence of alpha-amylase in the dissolution medium on the release rate. The addition of HPMC to CLA protected the tablets against alpha-amylase hydrolysis and reduced the release rate of prednisone and sodium diclofenac. The release of pseudoephedrine sulfate was fast and independent of HPMC and occurred mainly by diffusion.     

Zoonotic focus of plague, Algeria

After an outbreak of human plague, 95 Xenopsylla cheopis fleas from Algeria were tested for Yersinia pestis with PCR methods. Nine fleas were definitively confirmed to be infected with Y. pestis biovar orientalis. Our results demonstrate the persistence of a zoonotic focus of Y. pestis in Algeria.     

Sustaining GAVI-supported vaccine introductions in resource-poor countries

Since 2000, GAVI provided essential support for an unprecedented increase in the use of hepatitis B (HepB) and Haemophilus influenzae (Hib) containing vaccines in resource poor countries. This increase was supported with significant funding from international donors, intended to be time-limited. To assess the sustainability of this important expansion of the global access to vaccines, we reviewed supply chains, financial resources for procurement and decision-making in countries that introduced hepatitis B or Hib vaccines with GAVI support. During the period studied, the types of vaccine products supplied fluctuated rapidly in relationship with the number of suppliers and availability of more combination products. The price of the cheaper vaccines decreased while that of pentavalent DTwP-HepB-Hib remained stable. In average, vaccine introduction was associated with an increase of national programs budget, with new vaccines representing more than half of that increase, while the part of GAVI contributions to the budget went from 25% to 46%. Less than 20% of the vaccine introductions were decided by a national advisory body. Strengthening supply chains, adjusting funding schemes and increasing national ownership will be key to the sustained use of hepatitis B and Hib vaccines and the eventual addition of other important vaccines where they are the most needed.     

Cutaneous penetration of bisphenol A in pig skin

Bisphenol A (BPA) is an endocrine disruptor with weak estrogenic activity, used in epoxy resin and polycarbonate plastic. Human exposure may occur by contamination from food or food-contact material and by occupational scenarios. Occupational health hazards may be associated with allergic contact dermatitis (ACD) secondary to BPA exposure. Most ACD occurs in workers handling BPA products, such as plastic-product workers, and those exposed to epoxy adhesive tapes, foams, and dental products. The present study examined in vitro cutaneous penetration of BPA through pig skin, using a Franz cell. After 2, 5, and 10 h of exposure, total BPA skin content was 3, 6.9, and 11.4% of the applied dose, respectively. BPA remained essentially on the skin surface and penetration mainly accumulated in the dermis. As the pig skin model is a reliable predictor of percutaneous penetration in humans, these findings may be reassuring for workers in contact with BPA-based products.     

Indigence and access to health care in sub‐Saharan Africa

Access to health care services for the poor and indigent is hampered by current policies of health care financing in sub‐Saharan Africa. This paper reviews the issue as it is discussed in the international literature. No real strategies seem to exist for covering the health care of the indigent. Frequently, definitions of poverty and indigence are imprecise, the assessment of indigence is difficult for conceptual and technical reasons, and, therefore, the actual extent of indigence in Africa is not well known. Explicit policies rarely exist, and systematic evaluation of experiences is scarce. Results in terms of adequately identifying the indigent, and of mechanisms to improve indigents' access to health care, are rather deceiving. Policies to reduce poverty, and improve indigents' access to health care, seem to pursue strategies of depoliticizing the issue of social injustice and inequities. The problem is treated in a ‘technical’ manner, identifying and implementing ‘operational’ measures of social assistance. This approach, however, cannot resolve the problem of social exclusion, and, consequently, the problem of excluding large parts of African populations from modern health care. Therefore, this approach has to be integrated into a more ‘political’ approach which is interested in the process of impoverishment, and which addresses the macro‐economic and social causes of poverty and inequity. Copyright © 1999 John Wiley & Sons, Ltd.     

Effects of esmolol on systemic and pulmonary hemodynamics and on oxygenation in pigs with hypodynamic endotoxin shock

Purpose  

The aim of this experimental study is to investigate cardiovascular tolerance of blockade of beta-adrenergic receptors in an endotoxin model.     

Cross-cultural comparison of mental illness stigma and help-seeking attitudes: a multinational population-based study from 16 Arab countries and 10,036 individuals

Social Psychiatry and Psychiatric Epidemiology - There is evidence that culture deeply affects beliefs about mental illnesses' causes, treatment, and help-seeking. We aimed to explore and...     

Prognostic value of miR-16 expression in childhood acute lymphoblastic leukemia relationships to normal and malignant lymphocyte proliferation

miR-16, a miRNA involved in cell proliferation and apoptosis regulation, may interfere with either oncogenic or tumor-suppressor pathways and is implicated in leukemogenesis. We then explored its expression in 93 childhood acute lymphoblastic leukemia (ALL) cases. A high miR-16 expression was associated with hyperleukocytosis and poor cytogenetic groups. In the whole group and in B-cell ALLs, disease-free survival (DFS) was significantly shorter for miR-16 above quartile 75. In T-cell ALLs, for both DFS and overall survival, a significant trend was found with a survival shortening from the lowest to the highest miR-16 levels. miR-16 expression neither significantly correlated with normal and malignant lymphocyte proliferation nor varied according to lymphocyte differentiation. The prognostic value of miR-16 in childhood ALL highlighted the complexity of miR-16 functions.