Comparing changes in haematologic parameters occurring in patients included in randomized controlled trials of artesunate-amodiaquine vs single and combination treatments of uncomplicated falciparum in sub-Saharan Africa

<p>Abstract</p> <p>Background</p> <p>Artesunate-amodiaquine (AS&AQ) is a widely used artemisinin combination therapy (ACT) for falciparum malaria. A comprehensive appreciation of its effects on haematology <it>vs </it>other anti-malarials is needed in view of potential safety liabilities.</p> <p>Methods</p> <p>Individual-patient data analysis conducted on a database from seven randomized controlled trials conducted in sub-Saharan African comparing AS&AQ to reference treatments in uncomplicated falciparum malaria patients of all ages. Haematologic values (white cells total and neutrophil counts, haemoglobin/haematocrit, platelets) were analysed as both continuous and categorical variables for their occurrence, (severity grade 1-4) and changes during follow-up. Risks and trends were calculated using multivariate logistic random effect models.</p> <p>Results</p> <p>4,502 patients (72% < 5 years old), from 13 sites in nine countries with 28-day follow-up were treated with AS&AQ (45%) or a comparator (other forms of ACT accounted for 27%, other combination 12%, mono-therapies 16%). Pre-treatment leucopaenia (3%) and neutropaenia (6%) were infrequent; anaemia was common (39%). The treatment-emergent adverse events incidence (TEAE = condition not present or less severe pre-treatment) was 11% for neutropaenia, 6% for thrombocytopaenia with AS&AQ and not different from treatment groups; anaemia was higher with AS&AQ (20%) or other forms of ACT (22%) than in non-artemisinin groups (4%, <it>p </it>= 0.001). Multivariate analysis showed that the risk of anaemia, thrombocytopaenia, and leucopaenia decreased with follow-up time, while neutropaenia increased; the risk of anaemia and thrombocytopaenia increased with higher baseline parasitaemia and parasitological reappearance. White cells total count was not a good surrogate for neutropaenia. No systematic significant difference between treatments was detected. Older patients were at lower risks.</p> <p>Conclusion</p> <p>The effects of AS&AQ on haematologic parameters were not different from those of other anti-malarial treatments used in sub-Saharan Africa. This analysis provides the basis for a broader evaluation of haematology following anti-malarial treatment. Continuing monitoring of haematologic safety on larger databases is required.</p

Fixation of the Cemented Stem: Clinical Relevance of the Porosity and Thickness of the Cement Mantle

The aim of this review paper is to define the fixation of the cemented stem. Polymethyl methacrylate, otherwise known as “bone cement”, has been used in the fixation of hip implants since the early 1960s. Sir John Charnley, the pioneer of modern hip replacement, incorporated the use of cement in the development of low frictional torque hip arthroplasty. In this paper, the concepts of femoral stem design and fixation, clinical results, and advances in understanding of the optimal use of cement are reviewed. The purpose of this paper is to help understanding and discussions on the thickness and the porosity of the cement mantle in total hip arthroplasty. Cement does not act as an adhesive, as sometimes thought, but relies on an interlocking fit to provide mechanical stability at the cement–bone interface, while at the prosthesis– cement interface it achieves stability by optimizing the fit of the implant in the cement mantle, such as in a tapered femoral stem

Basic Science Considerations in Primary Total Hip Replacement Arthroplasty

Total Hip Replacement is one of the most common operations performed in the developed world today. An increasingly ageing population means that the numbers of people undergoing this operation is set to rise. There are a numerous number of prosthesis on the market and it is often difficult to choose between them. It is therefore necessary to have a good understanding of the basic scientific principles in Total Hip Replacement and the evidence base underpinning them. This paper reviews the relevant anatomical and biomechanical principles in THA. It goes on to elaborate on the structural properties of materials used in modern implants and looks at the evidence base for different types of fixation including cemented and uncemented components. Modern bearing surfaces are discussed in addition to the scientific basis of various surface engineering modifications in THA prostheses. The basic science considerations in component alignment and abductor tension are also discussed. A brief discussion on modular and custom designs of THR is also included. This article reviews basic science concepts and the rationale underpinning the use of the femoral and acetabular component in total hip replacement

Determinants of director compensation in two-tier systems: evidence from German panel data

Building on a unique panel data set of German Prime Standard companies for the period 2005-2008, this paper investigates the influencing factors of both director compensation levels and structure, i.e. the probability of performance-based compensation. Drawing on agency theory arguments and previous literature, we analyze a comprehensive group of determinants, including detailed corporate performance, ownership and board characteristics. While controlling for unobserved heterogeneity, we find director compensation to be set in ways consistent with optimal contracting theory. I.e. compensation is systematically structured to mitigate agency conflicts and to encourage effective monitoring. Thus, our results indicate that similar types of agency conflicts exist in the German two-tier setting

Medial Unicompartmental Knee Replacement Using the "Oxford Uni" Meniscal Bearing Knee

Medial unicompartmental knee replacement (UKR) has many advantages over total replacement (TKR) including better function and less morbidity. However, the long-term failure rates of fixed-bearing UKR are high because of polyethylene wear, lack of sophisticated instrumentation and imprecise patient selection. The fully congruent mobile bearing of the Oxford UKR exhibits minimal polyethylene wear and failure from this cause does not occur. The instrumentation allows precise implantation to restore isometric function to the ligaments. During its 20 years development, the limits of usefulness of the implant have been established and found to include about one in four knees requiring replacement for osteoarthritis. In an independent series, using these criteria, the 15 year survival was 94% (CI 86% to 100%). Since 1998, the Phase 3 implant has been used with modified instruments through a small incision, avoiding damage to the extensor mechanism. Patients now recover about three times faster than after TKR, and regain much better flexion (mean 135°). The current evidence supports that the minimally invasive Oxford UKR should be seriously considered as primary treatment and discussed with the patient presenting with anteromedial compartment osteoarthritis provided the correct indication and the appropriate surgical expertise is available