C-reactive protein mediates CD11b expression in monocytes through the non-receptor tyrosine kinase, Syk, and calcium mobilization but not through cytosolic peroxides

Objective: C-Reactive protein (CRP) can modulate integrin surface expression on monocytes following Fcγ receptor engagement. We have investigated the signal transduction events causing this phenotypic alteration. Methods: CRP-induced signalling events were examined in THP-1 and primary monocytes, measuring Syk phosphorylation by Western blotting, intracellular Ca2+ ([Ca2+]i) by Indo-1 fluorescence and surface expression of CD11b by flow cytometry. Cytosolic peroxides were determined by DCF fluorescence. Results: CRP induced phosphorylation of Syk and an increase in [Ca2+]i both of which were inhibitable by the Syk specific antagonist, piceatannol. Piceatannol also inhibited the CRP-induced increase in surface CD11b. In addition, pre-treatment of primary monoytes with the Ca2+ mobiliser, thapsigargin, increased CD11b expression; this effect was accentuated in the presence of CRP but was abolished in the presence of the [Ca2+]i chelator, BAPTA. CRP also increased cytosolic peroxide levels; this effect was attenuated by antioxidants (ascorbate, α-tocopherol), expression of surface CD11b not being inhibited by antioxidants alone. Conclusion: CRP induces CD11b expression in monocytes through a peroxide independent pathway involving both Syk phosphorylation and [Ca2+]i release. © Birkhäuser Verlag, 2005.

Objective grading of the anterior eye

Purpose. To convert objective image analysis of anterior ocular surfaces into recognisable clinical grades, in order to provide a more sensitive and reliable equivalent to current subjective grading methods; a prospective, randomized study correlating clinical grading with digital image assessment. Methods. The possible range of clinical presentations Of bulbar and palpebral hyperaemia, palpebral roughness and corneal staining were represented by 4 sets of 10 images. The images were displayed in random order and graded by 50 clinicians using both subjective CCLRU and Efron grading scales. Previously validated objective image analysis was performed 3 times oil each of the 40 images. Digital measures included edge-detection and relative-coloration components. Step-wise regression analysis determined correlations between the average subjective grade and the objective image analysis measures. Results. Average subjective grades Could be predicted by a combination of the objective image analysis components. These digital ``grades'' accounted for between 69%, (for Efron scale-graded palpebral redness) and 98% (for Efron scale-graded bulbar hyperaemia) of the subjective variance. Conclusions. The results indicate that clinicians may use a combination of vessel areas and overall hue in their judgment of clinical severity for certain conditions. Objective grading call take these aspects into account, and be used to predict an average ``objective grade'' to be used by a clinician in describing the anterior eye. These measures are more sensitive and reliable than subjective grading while still utilizing familiar terminology, and can be applied in research or practice to improve the detection, and monitoring of ocular surface changes.

Pro-inflammatory cytokines IL6, TNF-α, IL1β, procalcitonin, lipopolysaccharide binding protein and C-reactive protein in infective endocarditis

Objective: To evaluate the serum levels and diagnostic value of cytokines and acute phase proteins in patients with infective endocarditis (IE). Patients and methods: Serum samples from 63 patients diagnosed with IE and 71 control patients were analysed for the following markers: interleukin-6 (IL6), tumour necrosis factor-α (TNF-α), interleukin 1-β (IL1β), procalcitonin (PCT), lipopolysaccharide binding protein (LBP) and C-reactive protein (CRP). Results: Serum levels of IL6, IL1β and CRP were significantly elevated in patients with IE as compared to controls. PCT, TNF-α and LBP were not elevated. Conclusion: Serum CRP and IL6 are elevated in IE. IL 6 may aid in establishing the diagnosis. There was no correlation between IL 6 levels and CRP, causative microorganism, echocardiographic features or outcome. © 2007 The British Infection Society.

An evaluation of quinolone prescribing in a group of acute hospitals:Development of an objective measure of usage

Objectives: To develop an objective measure to enable hospital Trusts to compare their use of antibiotics. Design: Self-completion, postal questionnaire with telephone follow up. Sample: 4 hospital trusts in the English Midlands. Results: The survey showed that it was possible to collect data concerning the number of Defined Daily Doses (DDD's) of quinolone antibiotic dispensed per Finished Consultant Episode (FCE) in each Trust.. In the 4 trusts studied the mean DDD/FCE was 0.197 (range 0.117 to 0.258). This indicates that based on a typical course length of 5 days, 3.9% of patient episodes resulted in the prescription of a quinolone antibiotic. Antibiotic prescribing control measures in each Trust were found to be comparable. Conclusion: The measure will enable Trusts to objectively compare their usage of quinolone antibiotics and use this information to carry out clinical audit should differences be recorded. This is likely to be applicable to other groups of antibiotics.

The Role of protein kinase C modulation in the antiproliferative effects of bistratene A, bryostatin 1 and phorbol esters

PKC-mediated signalling pathways are important in cell growth and differentiation, and aberrations in these pathways are implicated in tumourigenesis. The objective of this project was to clarify the link between cell growth inhibition and PKC modulation.The PKC activators bryostatin 1 and 12-0-tetradecanoylphorbol-13-acetate (TPA) inhibited growth in A549 and MCF-7 adenocarcinoma cells with great potency, and induced HL-60 leukaemia cell differentiation. Bistratene A affected these cells similarly. Experiments were conducted to test the hypotheses that bistratene A exerts its effects via PKC modulation and that characteristics of cytostasis induced by bryostatin 1 and TPA depend upon PKC isozyme-specific events. After incubation of A549 cells with TPA or bistratene A, 2D phosphoprotein electrophoretograrns revealed three proteins phosphorylated by both agents. However, bistratene A was unable to induce the formation of cellular networks on the basement membrane substitute Matrigel, and staurosporine was unable to reverse bistratene A-induced [3H]thymidine uptake inhibition, unlike TPA. Bistratene A did not induce PKC translocation or downregulation, activate or inhibit A549 and MCF-7 cell cytosolic PKC or compete for phorbol ester receptors. Western blot analysis and hydroxylapatite chromatography identified PKC α, ε and ζ in these cells. Bistratene A was unable to activate any of these isoforms. Therefore the agent does not exert its antiproliferative effects by modulation of PKC activity. The abilities of bryostatin 1 and TPA (10nM-1μM) to induce PKC isoform translocation and downregulation were compared with antiproliferative effects. Both agents induced dose-dependent downregulation and translocation of PKC α and ε to particulate and nuclear cell fractions. PKC ζ was translocated to the particulate fraction by both agents in MCF-7 cells. The similarity of PKC isoform redistribution by these agents did not explain their divergent effects on cell growth, and the role of nuclear translocation of PKC in cytostasis was not confirmed by these studies. Alternative factors governing the characteristics of growth inhibition induced by these agents are discussed.

Objective methods for anterior ocular grading

This thesis set out to develop an objective analysis programme that correlates with subjective grades but has improved sensitivity and reliability in its measures so that the possibility of early detection and reliable monitoring of changes in anterior ocular surfaces (bulbar hyperaemia, palpebral redness, palpebral roughness and corneal straining) could be increased. The sensitivity of the program was 20x greater than subjective grading by optometrists. The reliability was found to be optimal (r=1.0) with subjective grading up to 144x more variable (r=0.08). Objective measures were used to create formulae for an overall ‘objective-grade’ (per surface) equivalent to those displayed by the CCLRU or Efron scales. The correlation between the formulated objective verses subjective grades was high, with adjusted r2 up to 0.96. Determination of baseline levels of objective grade were investigated over four age groups (5-85years n= 120) so that in practice a comparison against the ‘normal limits’ could be made. Differences for bulbar hyperaemia were found between the age groups (p<0.001), and also for palpebral redness and roughness (p<0.001). The objective formulae were then applied to the investigation of diurnal variation in order to account for any change that may affect the baseline. Increases in bulbar hyperaemia and palpebral redness were found between examinations in the morning and evening. Correlation factors were recommended. The program was then applied to clinical situations in the form of a contact lens trial and an investigation into iritis and keratoconus where it successfully recognised various surface changes. This programme could become a valuable tool, greatly improving the chances of early detection of anterior ocular abnormalities, and facilitating reliable monitoring of disease progression in clinical as well as research environments.

Constructing institutional change: emergence, contestation and convergence of business models in the field of Java application servers

How are innovative new business models established if organizations constantly compare themselves against existing criteria and expectations? The objective is to address this question from the perspective of innovators and their ability to redefine established expectations and evaluation criteria. The research questions ask whether there are discernible patterns of discursive action through which innovators theorize institutional change and what role such theorizations play for mobilizing support and realizing change projects. These questions are investigated through a case study on a critical area of enterprise computing software, Java application servers. In the present case, business practices and models were already well established among incumbents with critical market areas allocated to few dominant firms. Fringe players started experimenting with a new business approach of selling services around freely available opensource application servers. While most new players struggled, one new entrant succeeded in leading incumbents to adopt and compete on the new model. The case demonstrates that innovative and substantially new models and practices are established in organizational fields when innovators are able to refine expectations and evaluation criteria within an organisational field. The study addresses the theoretical paradox of embedded agency. Actors who are embedded in prevailing institutional logics and structures find it hard to perceive potentially disruptive opportunities that fall outside existing ways of doing things. Changing prevailing institutional logics and structures requires strategic and institutional work aimed at overcoming barriers to innovation. The study addresses this problem through the lens of (new) institutional theory. This discourse methodology traces the process through which innovators were able to establish a new social and business model in the field.

The development of an objective methodology to measure medication adherence to oral thiopurines in paediatric patients with acute lymphoblastic leukaemia - an exploratory study

Aims - To develop a method that prospectively assesses adherence rates in paediatric patients with acute lymphoblastic leukaemia (ALL) who are receiving the oral thiopurine treatment 6-mercaptopurine (6-MP). Methods - A total of 19 paediatric patients with ALL who were receiving 6-MP therapy were enrolled in this study. A new objective tool (hierarchical cluster analysis of drug metabolite concentrations) was explored as a novel approach to assess non-adherence to oral thiopurines, in combination with other objective measures (the pattern of variability in 6-thioguanine nucleotide erythrocyte concentrations and 6-thiouric acid plasma levels) and the subjective measure of self-reported adherence questionnaire. Results - Parents of five ALL patients (26.3%) reported at least one aspect of non-adherence, with the majority (80%) citing “carelessness at times about taking medication” as the primary reason for non-adherence followed by “forgetting to take the medication” (60%). Of these patients, three (15.8%) were considered non-adherent to medication according to the self-reported adherence questionnaire (scored ≥ 2). Four ALL patients (21.1%) had metabolite profiles indicative of non-adherence (persistently low levels of metabolites and/or metabolite levels clustered variably with time). Out of these four patients, two (50%) admitted non-adherence to therapy. Overall, when both methods were combined, five patients (26.3%) were considered non-adherent to medication, with higher age representing a risk factor for non-adherence (P < 0.05). Conclusions - The present study explored various ways to assess adherence rates to thiopurine medication in ALL patients and highlighted the importance of combining both objective and subjective measures as a better way to assess adherence to oral thiopurines.