Induction of inflammatory cytokines and nitric oxide in J774.2 cells and murine macrophages by lipoteichoic acid and related cell wall antigens from Staphylococcus epidermidis

Staphylococcus epidermidis causes infections associated with medical devices including central venous catheters, orthopaedic prosthetic joints and artificial heart valves. This coagulase-negative Staphylococcus produces a conventional cellular lipoteichoic acid (LTA) and also releases a short-glycerophosphate-chain-length form of LTA (previously termed lipid S) into the medium during growth. The relative pro-inflammatory activities of cellular and short-chain-length exocellular LTA were investigated in comparison with peptidoglycan and wall teichoic acid from S. epidermidis and LPS from Escherichia coli O111. The ability of these components to stimulate the production of proinflammatory cytokines [interleukin (IL)-1β, IL-6 and tumour necrosis factor (TNF)-α] and nitric oxide was investigated in a murine macrophage-like cell line (J774.2), and in peritoneal and splenic macrophages. On a weight-for-weight basis the short-chain-length exocellular LTA was the most active of the S. epidermidis products, stimulating significant amounts of each of the inflammatory cytokines and nitric oxide, although it was approximately 100-fold less active than LPS from E. coli. By comparison the full-chain-length cellular LTA and peptidoglycan were less active and the wall teichoic acid had no activity. As an exocellular product potentially released from S. epidermidis biofilms, the short-chain-length exocellular LTA may act as the prime mediator of the host inflammatory response to device-related infection by this organism and act as the Gram-positive equivalent of LPS in Gram-negative sepsis. The understanding of the role of short-chain-length exocellular LTA in Gram-positive sepsis may lead to improved treatment strategies. © 2005 SGM.

Evaluation of the Heart of Birmingham teaching Primary Care Trust (HoBtPCT): My Choice Weight Management Programme:report commissioned by Heart of Birmingham teaching Primary Care Trust

This report details an evaluation of the My Choice Weight Management Programme undertaken by a research team from the School of Pharmacy at Aston University. The My Choice Weight Management Programme is delivered through community pharmacies and general practitioners (GPs) contracted to provide services by the Heart of Birmingham teaching Primary Care Trust. It is designed to support individuals who are ‘ready to change’ by enabling the individual to work with a trained healthcare worker (for example, a healthcare assistant, practice nurse or pharmacy assistant) to develop a care plan designed to enable the individual to lose 5-10% of their current weight. The Programme aims to reduce adult obesity levels; improve access to overweight and obesity management services in primary care; improve diet and nutrition; promote healthy weight and increased levels of physical activity in overweight or obese patients; and support patients to make lifestyle changes to enable them to lose weight. The Programme is available for obese patients over 18 years old who have a Body Mass Index (BMI) greater than 30 kg/m2 (greater than 25 kg/m2 in Asian patients) or greater than 28 kg/m2 (greater than 23.5 kg/m2 in Asian patients) in patients with co-morbidities (diabetes, high blood pressure, cardiovascular disease). Each participant attends weekly consultations over a twelve session period (the final iteration of these weekly sessions is referred to as ‘session twelve’ in this report). They are then offered up to three follow up appointments for up to six months at two monthly intervals (the final of these follow ups, taking place at approximately nine months post recruitment, is referred to as ‘session fifteen’ in this report). A review of the literature highlights the dearth of published research on the effectiveness of primary care- or community-based weight management interventions. This report may help to address this knowledge deficit. A total of 451 individuals were recruited on to the My Choice Weight Management Programme. More participants were recruited at GP surgeries (n=268) than at community pharmacies (n=183). In total, 204 participants (GP n=102; pharmacy n=102) attended session twelve and 82 participants (GP n=22; pharmacy 60) attended session fifteen. The unique demographic characteristics of My Choice Weight Management Programme participants – participants were recruited from areas with high levels of socioeconomic deprivation and over four-fifths of participants were from Black and Minority Ethnic groups; populations which are traditionally underserved by healthcare interventions – make the achievements of the Programme particularly notable. The mean weight loss at session 12 was 3.8 kg (equivalent to a reduction of 4.0% of initial weight) among GP surgery participants and 2.4 kg (2.8%) among pharmacy participants. At session 15 mean weight loss was 2.3 kg (2.2%) among GP surgery participants and 3.4 kg (4.0%) among pharmacy participants. The My Choice Weight Management Programme improved the general health status of participants between recruitment and session twelve as measured by the validated SF-12 questionnaire. While cost data is presented in this report, it is unclear which provider type delivered the Programme more cost-effectively. Attendance rates on the Programme were consistently better among pharmacy participants than among GP participants. The opinions of programme participants (both those who attended regularly and those who failed to attend as expected) and programme providers were explored via semi-structured interviews and, in the case of the participants, a selfcompletion postal questionnaire. These data suggest that the Programme was almost uniformly popular with both the deliverers of the Programme and participants on the Programme with 83% of questionnaire respondents indicating that they would be happy to recommend the Programme to other people looking to lose weight. Our recommendations, based on the evidence provided in this report, include: a. Any consideration of an extension to the study also giving comparable consideration to an extension of the Programme evaluation. The feasibility of assigning participants to a pharmacy provider or a GP provider via a central allocation system should also be examined. This would address imbalances in participant recruitment levels between provider type and allow for more accurate comparison of the effectiveness in the delivery of the Programme between GP surgeries and community pharmacies by increasing the homogeneity of participants at each type of site and increasing the number of Programme participants overall. b. Widespread dissemination of the findings from this review of the My Choice Weight Management Project should be undertaken through a variety of channels. c. Consideration of the inclusion of the following key aspects of the My Choice Weight Management Project in any extension to the Programme: i. The provision of training to staff in GP surgeries and community pharmacies responsible for delivery of the Programme prior to patient recruitment. ii. Maintaining the level of healthcare staff input to the Programme. iii. The regular schedule of appointments with Programme participants. iv. The provision of an increased variety of printed material. d. A simplification of the data collection method used by the Programme commissioners at the individual Programme delivery sites.

A biological-inspired support frame for an artificial cornea

Bilateral corneal blindness represents a quarter of the total blind, world-wide. The artificial cornea in assorted forms, was developed to replace opaque non-functional corneas and to return sight in otherwise hopeless cases that were not amenable to corneal grafts; believed to be 2% of corneal blind. Despite technological advances in materials design and tissue engineering no artificial cornea has provided absolute, long-term success. Formidable problems exist, due to a combination of unpredictable wound healing and unmanageable pathology. To have a solid guarantee of reliable success an artificial cornea must possess three attributes: an optical window to replace the opaque cornea; a strong, long term union to surrounding ocular tissue; and the ability to induce desired host responses. A unique artificial cornea possesses all three functional attributes- the Osteo-odonto-keratoprosthesis (OOKP). The OOKP has a high success rate and can survive for up to twenty years, but it is complicated both in structure and in surgical procedure; it is expensive and not universally available. The aim of this project was to develop a synthetic substitute for the OOKP, based upon key features of the tooth and bone structure. In doing so, surgical complexity and biological complications would be reduced. Analysis of the biological effectiveness of the OOKP showed that the structure of bone was the most crucial component for implant retention. An experimental semi-rigid hydroxyapatite framework was fabricated with a complex bone-like architecture, which could be fused to the optical window. The first method for making such a framework, was pressing and sintering of hydroxyapatite powders; however, it was not possible to fabricate a void architecture with the correct sizes and uniformity of pores. Ceramers were synthesised using alternative pore forming methods, providing for improved mechanical properties and stronger attachment to the plastic optical window. Naturally occurring skeletal structures closely match the structural features of all forms of natural bone. Synthetic casts were fabricated using the replamineform process, of desirable natural artifacts, such as coral and sponges. The final method of construction by-passed ceramic fabrication in favour of pre-formed coral derivatives and focused on methods for polymer infiltration, adhesion and fabrication. Prototypes were constructed and evaluated; a fully penetrative synthetic OOKP analogue was fabricated according to the dimensions of the OOKP. Fabrication of the cornea shaped OOKP synthetic analogue was also attempted.

Pulse oximetry screening for congenital heart defects in newborn infants:an evaluation of acceptability to mothers

Background: Introducing neonatal screening procedures may not be readily accepted by parents and may increase anxiety. The acceptability of pulse oximetry screening to parents has not been previously reported. Objective: To assess maternal acceptability of pulse oximetry screening for congenital heart defects and to identify factors predictive of participation in screening. Design and setting: A questionnaire was completed by a cross-sectional sample of mothers whose babies were recruited into the PulseOx Study which investigated the test accuracy of pulse oximetry screening. Participants: A total of 119 mothers of babies with false-positive (FP) results, 15 with true-positive and 679 with true-negative results following screening. Main outcome measures: Questionnaires included measures of satisfaction with screening, anxiety, depression and perceptions of test results. Results: Participants were predominantly satisfied with screening. The anxiety of mothers given FP results was not significantly higher than that of mothers given true-negative results (median score 32.7 vs 30.0, p=0.09). White British/Irish mothers were more likely to participate in screening, with a decline rate of 5%; other ethnic groups were more likely to decline with the largest increase in declining being for Black African mothers (21%, OR 4.6, 95% CI 3.8 to 5.5). White British mothers were also less anxious (p<0.001) and more satisfied (p<0.001) than those of other ethnicities Conclusions: Pulse oximetry screening was acceptable to mothers and FP results were not found to increase anxiety. Factors leading to differences in participation and satisfaction across ethnic groups need to be identified so that staff can support parents appropriately.

The formulation of artificial reference standards for use within the ELISPOT assay

Whether to assess the functionality of equipment or as a determinate for the accuracy of assays, reference standards are essential for the purposes of standardisation and validation. The ELISPOT assay, developed over thirty years ago, has emerged as a leading immunological assay in the development of novel vaccines for the assessment of efficacy. However, with its widespread use, there is a growing demand for a greater level of standardisation across different laboratories. One of the major difficulties in achieving this goal has been the lack of definitive reference standards. This is partly due to the ex vivo nature of the assay, which relies on cells being placed directly into the wells. Thus, the aim of this thesis was to produce an artificial reference standard using liposomes, for use within the assay. Liposomes are spherical bilayer vesicles with an enclosed aqueous compartment and therefore are models for biological membranes. Initial work examined pre-design considerations in order to produce an optimal formulation that would closely mimic the action of the cells ordinarily placed on the assay. Recognition of the structural differences between liposomes and cells led to the formulation of liposomes with increased density. This was achieved by using a synthesised cholesterol analogue. By incorporating this cholesterol analogue in liposomes, increased sedimentation rates were observed within the first few hours. The optimal liposome formulation from these studies was composed of 2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), cholesterol (Chol) and brominated cholesterol (Brchol) at a 16:4:12 µMol ratio, based on a significantly higher (p<0.01) sedimentation (as determined by a percentage transmission of 59 ± 5.9 % compared to the control formulation at 29 ± 12 % after four hours). By considering a range of liposome formulations ‘proof of principle’ for using liposomes as ELISPOT reference standards was shown; recombinant IFN? cytokine was successfully entrapped within vesicles of different lipid compositions, which were able to promote spot formation within the ELISPOT assay. Using optimised liposome formulations composed of phosphatidylcholine with or without cholesterol (16 µMol total lipid) further development was undertaken to produce an optimised, scalable protocol for the production of liposomes as reference standards. A linear increase in spot number by the manipulation of cytokine concentration and/or lipid concentrations was not possible, potentially due to the saturation that occurred within the base of wells. Investigations into storage of the formulations demonstrated the feasibility of freezing and lyophilisation with disaccharide cryoprotectants, but also highlighted the need for further protocol optimisation to achieve a robust reference standard upon storage. Finally, the transfer of small-scale production to a medium lab-scale batch (40 mL) demonstrated this was feasible within the laboratory using the optimised protocol.

Free radical reaction products and antioxidant capacity in beating heart coronary artery surgery compared to conventional bypass

Oxygen-derived free radicals are important agents of tissue injury during ischemia and reperfusion. The aim of this study was to investigate changes in protein and lipid oxidation and antioxidant status in beating heart coronary artery surgery and conventional bypass and to compare oxidative stress parameters between the two bypass methods. Serum lipid hydroperoxide, nitric oxide, protein carbonyl, nitrotyrosine, vitamin E, and β-carotene levels and total antioxidant capacity were measured in blood of 30 patients undergoing beating heart coronary artery surgery (OPCAB, off-pump coronary artery bypass grafting) and 12 patients undergoing conventional bypass (CABG, on-pump coronary artery bypass grafting). In the OPCAB group, nitric oxide and nitrotyrosine levels decreased after reperfusion. Similarly, β-carotene level and total antioxidant capacity also decreased after anesthesia and reperfusion. In the CABG group, nitric oxide and nitrotyrosine levels decreased after ischemia and reperfusion. However, protein carbonyl levels elevated after ischemia and reperfusion. Vitamin E, β-carotene, and total antioxidant capacity decreased after ischemia and reperfusion. Significantly decreased nitration and impaired antioxidant status were seen after reperfusion in both groups. Moreover, elevated protein carbonyls were found in the CABG group. The off-pump procedure is associated with lower degree of oxidative stress than on-pump coronary surgery. © 2011 Pleiades Publishing, Ltd.