Patellofemoral joint arthroplasty: patient selection,surgical technique and outcomes

Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome.     

IgE-mediated regulation of IL-10 and type I IFN enhances rhinovirus-induced Th2 differentiation by primary human monocytes

Rhinovirus (RV) infections are linked to the development and exacerbation of allergic diseases including allergic asthma. IgE, another contributor to atopic disease pathogenesis, has been shown to regulate DC antiviral functions and influence T cell priming by monocytes. We previously demonstrated that IgE-mediated stimulation of monocytes alters multiple cellular functions including cytokine secretion, phagocytosis, and influenza-induced Th1 development. In this study, we investigate the effects of IgE-mediated stimulation on monocyte-driven, RV-induced T cell development utilizing primary human monocyte-T cell co-cultures. We demonstrate that IgE crosslinking of RV-exposed monocytes enhances monocyte-driven Th2 differentiation. This increase in RV-induced Th2 development was regulated by IgE-mediated inhibition of virus-induced type I IFN and induction of IL-10. These findings suggest an additional mechanism by which two clinically significant risk factors for allergic disease exacerbations—IgE-mediated stimulation and rhinovirus infection—may synergistically promote Th2 differentiation and allergic inflammation.     

Association of psychological and physiological measures of stress in health‐care professionals during an 8‐week mindfulness meditation program: mindfulness in practice

Work stress, burnout, and diminished empathy are prevalent issues for health‐care professionals. Mindfulness meditation (MM) is one commonly used strategy to manage stress. Measuring salivary cortisol allows for the assessment of serum cortisol level, a known stress level indicator. This study evaluated the association of subject‐reported stress symptoms and salivary cortisol in health‐care professionals, in an 8‐week MM program, with data collected prospectively at baseline and 8 weeks after program completion. Questionnaires [Profile of Mood States—Short Form (POMS‐SF), Maslach Burnout Inventory (MBI), and Interpersonal Reactivity Index (IRI)] measured mood, burnout and empathy. A paired t‐test between groups for pre/post‐salivary cortisol yielded no significant change. The POMS‐SF was most sensitive to change (mean increase 12.4; p = 0.020). Emotional exhaustion, measured in the MBI, was also affected by MM (mean decrease 4.54; p = 0.001). Changes in empathy may not have been captured due to either absence of effect of MM on empathy, subject number or scale sensitivity. Baseline and 8‐week correlations between salivary cortisol and survey results, and correlations between changes in these measures, were weak and not statistically significant. Nevertheless, psychometric results present a strong case for additional clinical trials of MM to reduce stress for health‐care professionals. Copyright © 2005 John Wiley & Sons, Ltd.     

Treatment of refractoriness to platelet transfusion by protein A column therapy

Ten thrombocytopenic patients (platelets < 10–24 × 10(9)/L) who were refractory to platelet transfusion were investigated for their responsiveness to staphylococcal protein A column therapy. Nine patients had previously been treated with steroids, intravenous immune globulin, and/or other forms of immunosuppressive therapy without improvement in their transfusion response. All patients were receiving multiple platelet transfusions without achieving 1-hour corrected count increments (CCIs) > or = 7500. Eight patients had antibodies that reacted with platelets and were directed against HLA class I antigens, ABO antigens, and/or platelet-specific alloantigens. Plasma (500-2000 mL) from each patient was passed over a protein A silica gel column and then returned to the patient. Patients received from 1 to 14 treatments. A positive response to protein A therapy was defined as at least a doubling of the pretreatment platelet count and/or two successive 10- to 120-minute posttransfusion CCIs > or = 7500. Following plasma treatments, 6 of 10 patients responded with daily platelet counts that averaged 48 +/− 11 × 10(9) per L as compared with counts of 16 +/− 7 × 10(9) per L (p < 0.0005) before treatment. Posttransfusion CCI values determined in four of these patients averaged 2480 +/− 810 and 10,010 +/− 3540 (p < 0.005) before and after treatment, respectively. In contrast, among the four unresponsive patients, platelet counts averaged 10 +/− 9 and 13 +/− 10 × 10(9) per L (p = NS), respectively, while posttransfusion CCIs were 700 +/− 1410 and 1520 +/− 2460 (p = NS), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)