Membrane type 1 matrix metalloproteinase is a crucial promoter of synovial invasion in human rheumatoid arthritis

Objective

A hallmark of rheumatoid arthritis (RA) is invasion of the synovial pannus into cartilage, and this process requires degradation of the collagen matrix. The aim of this study was to explore the role of one of the collagen‐degrading matrix metalloproteinases (MMPs), membrane type 1 MMP (MT1‐MMP), in synovial pannus invasiveness.

Methods

The expression and localization of MT1‐MMP in human RA pannus were investigated by Western blot analysis of primary synovial cells and immunohistochemical analysis of RA joint specimens. The functional role of MT1‐MMP was analyzed by 3‐dimensional (3‐D) collagen invasion assays and a cartilage invasion assay in the presence or absence of tissue inhibitor of metalloproteinases 1 (TIMP‐1), TIMP‐2, or GM6001. The effect of adenoviral expression of a dominant‐negative MT1‐MMP construct lacking a catalytic domain was also examined.

Results

MT1‐MMP was highly expressed at the pannus–cartilage junction in RA joints. Freshly isolated rheumatoid synovial tissue and isolated RA synovial fibroblasts invaded into a 3‐D collagen matrix in an MT1‐MMP–dependent manner. Invasion was blocked by TIMP‐2 and GM6001 but not by TIMP‐1. Invasion was also inhibited by the overexpression of a dominant‐negative MT1‐MMP, which inhibits collagenolytic activity and proMMP‐2 activation by MT1‐MMP on the cell surface. Synovial fibroblasts also invaded into cartilage in an MT1‐MMP–dependent manner. This process was further enhanced by removing aggrecan from the cartilage matrix.

Conclusion

MT1‐MMP serves as an essential collagen‐degrading proteinase during pannus invasion in human RA. Specific inhibition of MT1‐MMP–dependent invasion may represent a novel therapeutic strategy for RA.

     

Consenting futures: professional views on social, clinical and ethical aspects of information feedback to embryo donors in human embryonic stem cell research

This paper reports from an ongoing multidisciplinary, ethnographic study that is exploring the views, values and practices (the ethical frameworks) drawn on by professional staff in assisted conception units and stem cell laboratories in relation to embryo donation for research purposes, particularly human embryonic stem cell (hESC) research, in the UK. We focus here on the connection between possible incidental findings and the circumstances in which embryos are donated for hESC research, and report some of the uncertainties and dilemmas of our staff participants. We explore the views of our study participants in relation to two themes: (1) rights to information and anticipating how donors might be informed about future research findings and (2) occupational work goals and trust.     

Investigating the relationship between drug distribution in solid lipid matrices and dissolution behaviour using raman spectroscopy and mapping

In this study, in situ and mapping Raman spectroscopic measurements were used to investigate the physical structure of solid lipid extrudates and relate the structure to dissolution behaviour. Theophylline anhydrate was extruded with tripalmitin, with and without the water‐soluble polymer, polyethylene glycol 10000. Raman mapping of the extrudate cores revealed that drug particles of diverse size were dispersed in a continuous lipid phase with or without polyethylene glycol. At the surface, there was evidence of more mixing between the components. Previous characterisation by other methods suggested that the extrudate surface is covered predominantly by lipid, and the Raman mapping suggested that such a layer is in general less than a few micrometres thick. Nevertheless, the lipid layer dramatically reduced the drug dissolution rate. The extrudate cores were also mapped after a period of dissolution testing, and there was no evidence of a uniformly receding drug boundary in the extrudates during drug release. In situ Raman spectroscopy analysis during dissolution testing revealed that the drug distribution in the extrudate affected the formation of theophylline monohydrate. However, the drug release rate was primarily determined directly by drug distribution, with the solid‐state behaviour of the drug having a smaller influence. © 2009 Wiley‐Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 1464–1475, 2010     

Food allergy information resources for consumers, industry and regulators

Through the EU-funded InformAll project a stakeholder consultation was conducted to solicit the views of different stakeholders (allergic consumers, health professionals, retailers, manufacturers, caterers, regulators and risk assessors, and the general public) regarding what information about food allergy is required by these stakeholders. The outcomes of this consultation are presented both generally and specifically from the potential perspectives of different stakeholders. The development of reliable credible resources aimed to begin to meet the needs identified is described, including a database of allergenic food materials which uniquely combines refereed information on the clinical aspects of food allergies with details of individual allergens and web portal with other credible internet resources.     

Do public access defibrillation (PAD) programmes lead to an increase of patients surviving to discharge from hospital following out of hospital cardiac arrest?--a literature review

OBJECTIVE: To ascertain the evidence for effectiveness of Public Access Defibrillation Programmes using any level of first responder. DATA SOURCES: Structured searches were made of Medline, Cinahl, Embase, and 'All EBM reviews' (CDSR, ACP Journal Club, DARE, CCTR). No limits were set on the searches in terms of date, publication type or language. Limited hand searches were carried out and colleagues approached for potential papers. REVIEW METHODS: All 491 results were 'hand searched' for suitability. Potential papers for inclusion were further reviewed by access to abstracts or full text if necessary. The final papers for review were assessed using a recognised checklist. RESULTS: Of a total of 491 results from all databases removal of repeats and papers that did not answer the question led to 22 papers being further reviewed. Of these 19 were excluded and a final three were assessed and reviewed. Of the three papers two were randomised controlled trials (one with cross over design) and one was a non-randomised controlled cross over trial. Two of the papers assessed the use of level one responders and one level two responders. Odds ratios for the trials using level one responders were 1.3 and 1.6. The relative risk (of survival) for the trial using level two responders was 2.0. However all three trials had wide confidence intervals. CONCLUSION: The use of level one responders probably carries a slight benefit for patients in OOHCA. The use of level two responders may lead to a greater benefit but only for a small section of the population suffering OOHCA. Emphasis must also be placed on the improvement of ambulance response times and bystander CPR rates.     

Implementation of multifactorial interventions for fall and fracture prevention

Over 60% of falls experienced by older people result from multiple aetiological factors. Preventing falls in individual patients requires the identification and treatment of these interacting factors. Multifactorial interventions have been successful in some, but not all, fall prevention trials. Preventing falls in populations requires selection of the population most likely to benefit, and selection of the particular interventions shown to have been effective in this group. The implementation of preventive measures has been low despite strong evidence that fall and fractures can be reduced. Misconceptions about the potential for prevention in old age, the time to effect improvement, resource issues and the nature of the interventions contribute to the low uptake. An improved system of delivery of proven preventive measures is needed.     

Prognosis of patients taking selective serotonin reuptake inhibitors before coronary artery bypass grafting

Depression is increasingly recognized as an independent prognostic risk factor in patients with coronary artery disease and coronary artery bypass grafting (CABG). The use of selective serotonin reuptake inhibitors (SSRIs) for depression in patients with cardiac disease is becoming more prevalent. We examined the long-term outcomes of patients on SSRIs before CABG. We prospectively examined collected data in the Duke Databank for Cardiovascular Disease from January 1, 1999 to December 31, 2003. The median and maximum follow-up periods were 3 and 6 years, respectively. We screened patients who underwent CABG (n = 5,364) and excluded those who underwent simultaneous CABG and valvular surgery (n = 570). SSRI antidepressants included fluoxetine, fluvoxamine, paroxetine, sertraline, citalopram, escitalopram, venlafaxine, and clomipramine, and their use was determined from the inpatient pharmacy records during the index hospitalization. Outcomes included event-free survival from all-cause mortality, rehospitalization, and a composite end point of all-cause mortality or rehospitalization. Of 4,794 CABG-only patients, 246 (5.1%) took SSRIs before CABG. The SSRI group had a higher prevalence of diabetes, hypercholesterolemia, hypertension, cerebrovascular disease, peripheral vascular disease, and previous cardiovascular intervention. After adjustment for baseline differences, patients on SSRIs before CABG had increased risks of mortality, rehospitalization, and the composite end point (hazard ratio 1.61, 95% confidence interval 1.17 to 2.21, p = 0.003; hazard ratio 1.52, 95% confidence interval 1.30 to 1.77, p <0.0001; and hazard ratio 1.46, 95% confidence interval 1.26 to 1.70, p <0.0001, respectively). In conclusion, SSRI use before CABG was associated with a higher risk of long-term post-CABG mortality and rehospitalization. The explanation behind these findings requires further research.