Barriers and facilitators for physical activity in rheumatic and musculoskeletal disease: a European-based survey.

Physical activity (PA) is a key strategy for improving symptoms in people with rheumatic and musculoskeletal diseases (RMDs). The aim of this study was to investigate and rank the importance of known barriers and facilitators for engaging in PA, from the perspective of people living with RMD. Five hundred thirty-three people with RMD responded to a survey (nine questions) disseminated by the People with Arthritis and Rheumatism (PARE) network of the European Alliance of Associations for Rheumatology (EULAR). The survey required participants to rank - based on their perceived importance - known PA barriers and facilitators from the literature, and specifically RMD symptoms as well as healthcare and community factors that may affect PA participation. Of the participants, 58% reported rheumatoid arthritis as their primary diagnosis, 89% were female, and 59% were between 51 and 70 years of age. Overall, participants reported fatigue (61.4%), pain (53.6%) and painful/swollen joints (50.6%) as the highest ranked barriers for engaging in PA. Conversely, less fatigue (66.8%) and pain (63.6%), and being able to do daily activities more easy (56.3%) were identified as the most important facilitators to PA. Three literature identified PA barriers, i.e., general health (78.8%), fitness (75.3%) and mental health (68.1%), were also ranked as being the most important for PA engagement. Symptoms of RMDs, such as pain and fatigue, seem to be considered the predominant barriers to PA by people with RMD; the same barriers are also the ones that they want to improve through increasing PA, suggesting a bi-directional relationship between these factors. Key Points • Symptoms of rheumatic and musculoskeletal disease (RMD) are the predominant barriers for lack of physical activity engagement. • RMD symptoms are the factors that people with RMDs want to improve when engaging in PA. • The barriers that stop people living with RMDs to do more PA are the ones that can be significantly improved through PA engagement.

The effects of exercise on cardiovascular disease risk factors and cardiovascular physiology in rheumatoid arthritis.

Cardiovascular disease (CVD) morbidity and mortality is highly prevalent in patients with rheumatoid arthritis (RA) with debilitating effects for the individual as well as significant healthcare impact. Current evidence demonstrates that engaging in aerobic and resistance exercise (i.e. structured physical activity) can significantly improve patient-reported and clinical index-assessed outcomes in RA. In addition to this, engagement in exercise programmes improves, in a dose-dependent manner, the risk of developing CVD as well as CVD symptoms and outcomes. The present narrative review uses evidence from systematic reviews and meta-analyses as well as controlled trials, to synthesize the current state-of-the-art on the potential effects of aerobic and resistance exercise on CVD risk factors as well as on cardiac and vascular function and structure in people with RA. Where there is a lack of evidence in RA to explain potential mechanisms, relevant studies from the general population are also discussed and linked to RA.

Negative affectivity predicts decreased pain tolerance during low-grade inflammation in healthy women.

INTRODUCTION: Experimental animal studies provided evidence for a synergistic effect of immunological and psychological stressors on subsequent sickness behaviours. Up to now, little corroborating evidence for such synergy exists for humans, in whom it may provide a mechanism leading to the expression of functional somatic symptoms. The aim of the present study was to determine an interaction between stress(-vulnerability) and an immunological activation on experimental pain sensitivity, i.e., pressure pain threshold and tolerance in healthy humans. METHODS: In healthy female participants (n=25, mean age 22.3 years), negative affectivity (NA) and experienced stress were assessed by questionnaire before receiving a Salmonella typhi vaccine or saline control in a randomized blinded cross-over design. Pressure pain threshold was assessed at the lower back and calves and pain tolerance was assessed at the thumbnail, before and six hours after each injection. RESULTS: Vaccination induced leukocytosis (+100%) and increased serum IL-6 (+670%). NA predicted decreased pain tolerance after vaccination (ß=-.57, p=.007), but not after placebo (ß=.25, p=.26). Post-hoc analyses also demonstrated an association with administration order. DISCUSSION: NA moderated the effects of inflammation on pain tolerance. This finding is consistent with a synergistic model whereby inflammation may lower the threshold for pain reporting in individuals with increased vulnerability for somatic symptom reporting.

Predictors of asymmetric dimethylarginine levels in patients with rheumatoid arthritis: the role of insulin resistance.

OBJECTIVE: To determine whether demographic, inflammatory, and metabolic factors predict elevated asymmetric dimethylarginine (ADMA) levels in rheumatoid arthritis (RA). METHOD: A total of 67 RA patients [mean age 56 ± 12 years, median disease duration 8 (3-15) years] were assessed. Routine biochemistry tests, lipid profile, glycaemic profile [glucose, insulin, homeostasis model assessment (HOMA), quantitative insulin sensitivity check index (QUICKI)], and inflammatory markers were measured in all patients. ADMA levels were measured by enzyme-linked immunosorbent assay (ELISA). Regression analyses were performed to identify predictors of ADMA in RA. RESULTS: Regression analysis revealed that HOMA (ß = 0.149, p = 0.003) was an independent predictor of ADMA in RA. From the drug factors, anti-hypertensive medication use was associated with lower ADMA levels (ß = -0.081, p = 0.004). ADMA was not associated with RA disease-related parameters or any of the other cardiovascular risk factors that were assessed. CONCLUSIONS: HOMA, a strong indicator of insulin resistance, seems to be the main predictor of elevated ADMA levels in RA patients; ADMA may reflect an important pathway linking abnormal insulin metabolism with endothelial dysfunction in RA.

Lack of association between asymmetric dimethylarginine and in vivo microvascular and macrovascular endothelial function in patients with rheumatoid arthritis.

OBJECTIVES: The aim of the present study was to investigate if assymetric dimethylarginine (ADMA) is increased in patients with rheumatoid arthritis (RA) compared to healthy controls and to examine associations between ADMA, RA disease activity and in vivo assessments of microvascular and macrovascular endothelial function. METHODS: Sixty-seven RA patients (age [mean ± standard deviation]: 56 ± 12 years, disease duration median [25th-75th percentile]: 8 [3-15] years, 48 women) and 29 healthy controls (age [mean ± standard deviation]: 42 ± 12, 21 women) underwent assessments of microvascular endothelial function (Laser Doppler imaging with iontophoresis of acetylcholine and sodium-nitroprusside), and macrovascular endothelial function (flow-mediated dilatation and glyceryl-trinitrate-mediated dilatation) as well as arterial stiffness. ADMA levels were measured in contemporary specimens using an immunoassay ELISA kit. RESULTS: ADMA levels were significantly higher (p=0.004) in RA patients compared with healthy controls after adjustment for age (difference=0.088, 95% confidence interval 0.029-0.147). ADMA levels did not correlate with demographic or disease characteristics. No correlation was found between ADMA and microvascular and macrovascular endothelial function or with arterial stiffness. CONCLUSIONS: ADMA levels are increased in patients with RA but there was no significant correlation with in vivo assessments of endothelial function. Further studies are needed to unfold the pathophysiological role of nitric oxide/ADMA pathway derangement in endothelial dysfunction and cardiovascular risk in RA.

Regulatory considerations in application of encapsulated cell therapies.

The encapsulation of tissue in semi-permeable membranes is a technology with high potential and in due time several new therapies based on this technology will be tested in clinical trials. Recent, new legislation requires that these investigational medicinal products used in clinical trials Phase I must be produced according to Good Manufacturing Practice (GMP). Consequently, the activities of GMP are expanding to the field of research and researchers might need to change developed protocols in order to meet GMP legislation. This chapters gives an overview of the overall guidelines covering GMP and more specific guidelines dealing with cell based therapies and gene therapy.

Rheumatoid arthritis, cardiovascular disease and physical exercise: a systematic review.

This systematic review investigates the effectiveness of exercise interventions in improving disease-related characteristics in patients with rheumatoid arthritis (RA). It also provides suggestions for exercise programmes suitable for improving the cardiovascular profile of RA patients and proposes areas for future research in the field. Six databases (Medline, Cochrane Library, CINAHL, Google Scholar, EMBASE and PEDro) were searched to identify publications from 1974 to December 2006 regarding RA and exercise interventions. The quality of the studies included was determined by using the Jadad scale. Initial searches identified 1342 articles from which 40 met the inclusion criteria. No studies were found investigating exercise interventions in relation to cardiovascular disease in RA. There is strong evidence suggesting that exercise from low to high intensity of various modes is effective in improving disease-related characteristics and functional ability in RA patients. Future studies are required to investigate the effects of exercise in improving the cardiovascular status of this patient population.

Closed system generation of dendritic cells from a single blood volume for clinical application in immunotherapy.

Dendritic cells (DC) used for clinical trials should be processed on a large scale conforming to current good manufacturing practice (cGMP) guidelines. The aim of this study was to develop a protocol for clinical grade generation of immature DC in a closed-system. Aphereses were performed with the Cobe Spectra continuous flow cell separator and material was derived from one volume of blood processed. Optimisation of a 3-phase collection autoPBSC technique significantly improved the quality of the initial mononuclear cell (MNC) product. Monocytes were then enriched from MNC by immunomagnetic depletion of CD19+ B cells and CD2+ T cells and partial depletion of NK cells using the Isolex 300I Magnetic cell selector. The quality of the initial mononuclear cell product was found to determine the outcome of monocyte enrichment. Enriched monocytes were cultured in Opticyte gas-permeable containers using CellGro serum-free medium supplemented with GM-CSF and IL-4 to generate immature DC. A seeding concentration of 1 x 10(6) was found optimal in terms of DC phenotype expression, monocyte percentage in culture, and cell viability. The differentiation pattern favours day 7 for harvest of immature DC. DC recovery, viability, as well as phenotype expression after cryopreservation of immature DC was considered in this study. DC were induced to maturation and evaluated in FACS analysis for phenotype expression and proliferation assays. Mature DC were able to generate an allogeneic T-cell response as well as an anti-CMV response as detected by proliferation assays. These data indicate that the described large-scale GMP-compatible system results in the generation of stable DC derived from one volume of blood processed, which are qualitatively and quantitatively sufficient for clinical application in immunotherapeutic protocols.

Increased C reactive protein in response to acute stress in patients with rheumatoid arthritis.

OBJECTIVE: To assess the effects of acute stress on inflammatory, haemostatic, rheological, and haemodynamic activity in patients with rheumatoid arthritis (RA) in comparison with patients with osteoarthritis (OA). METHODS: 21 patients with RA and 10 with OA underwent a brief mental stress task while standing. Inflammatory, haemostatic, rheological, and haemodynamic variables were measured at baseline, during the task, and at recovery. RESULTS: At baseline, erythrocyte sedimentation rate and fibrinogen were higher in RA than OA. White blood cell count, fibrinogen, blood pressure, and pulse rate increased, whereas prothrombin time and plasma volume decreased during the task in both patient groups. The stress task increased C reactive protein (CRP) only in patients with RA, and more specifically in those patients with RA with high disease activity. CONCLUSIONS: The increase in the inflammatory marker CRP, which was specific to patients with RA, combined with the haemostatic, rheological, and haemodynamic reactions to the stress task, over and above the already high baseline levels, could underlie the increased risk for myocardial infarction in this vulnerable patient group.

Association between macrophage activation and function of micro-encapsulated rat islets.

AIMS/HYPOTHESIS: Survival of microencapsulated islet grafts is limited, even when inflammatory reactions against the capsules are restricted to a small portion of less than 10%. METHODS: This study investigates both in vivo in rat recipients and in vitro whether cellular overgrowth on this minority of the capsules contributes to limitations in the functional survival of the 90% of the encapsulated islets which remain free of any cellular overgrowth. RESULTS: In successful rat recipients of an allogenic microencapsulated islet graft we found that the vast majority of cells in the capsular overgrowth were activated ED-1 and ED-2 positive macrophages which were found in numbers of approximately 1500 per capsule. Co-culture of encapsulated islets with 1500 (nr8383) rat-macrophages per capsule showed that the activation of macrophages was caused by islet-derived bioactive factors since TNF-alpha and IL-1beta secretion by macrophages was induced by islet-containing capsules and not by empty capsules. This activation of macrophages was associated with a decrease in function of the encapsulated islets as evidenced by a quantitatively reduced (35%) insulin response in static incubation and a slower response in perifusion. CONCLUSION/INTERPRETATION: Present research aims to design strategies for the temporary inhibition of macrophage activation since macrophages are predominantly present in the first two months after implantation. These strategies will serve as a pertinent basis for future clinical application of microencapsulated islets.

Dendritic cells present an intracellular viral antigen derived from apoptotic cells and induce a T-cell response.

We investigated if dendritic cells (DCs) were able to present intracellularly located antigens derived from apoptotic cells to T cells, thereby inducing a CD4+ and a CD8+ response. A transfected cell line with the cytomegalovirus-derived protein pp65 was triggered to go into apoptosis by ultraviolet B (UVB) irradiation, and after the uptake of apoptotic cells by DC, the activation and proliferation of T cells were determined. We found that DC efficiently phagocytosed apoptotic cells and induced a CD4+ and a CD8+ T-cell response specific for the viral protein pp65. This mechanism can be useful for vaccination studies to induce an antiviral immune response.

Monitoring DNA/poly-L-lysine polyplex formation with time-resolved multiangle laser light scattering.

Nonviral DNA complexes show promise as alternative and attractive gene delivery vectors for treating genetic diseases. Nonviral DNA complexes are typically formed by combining DNA with various condensing/complexing agents such as lipids, polyelectrolytes, polymers, polypeptides, and surfactants in solution. DNA/poly-L-lysine polyplex formation kinetics are probed by time-resolved multiangle laser light scattering (TR-MALLS), which yields the time evolution of the supramolecular complex mass and geometric size. Primary polyplexes whose geometric size is smaller than individual DNA molecules in solution are formed very rapidly upon mixing DNA and poly-L-lysine. Over time, these primary polyplexes aggregate into larger structures whose ultimate size is determined primarily by the relative concentrations of DNA and poly-L-lysine. This final polyplex size varies with the DNA/poly-L-lysine mass ratio in a non-monotonic fashion, with the maximum polyplex size occurring at a DNA/poly-L-lysine mass ratio of approximately two to three (charge ratio near unity). The utility of TR-MALLS for monitoring the temporal evolution of DNA loading and supramolecular complex size growth (mean square radius and molar mass) throughout the DNA/poly-L-lysine polyplex formation process is demonstrated. The polyplex DNA loading and size, both geometric and molar mass, are key to understanding the transfection process and for developing optimal gene therapy vectors.

Vesicle size distributions measured by flow field-flow fractionation coupled with multiangle light scattering.

The separation method, flow field-flow fractionation (flow FFF), is coupled on-line with multiangle laser light scattering (MALLS) for simultaneous measurement of the size and concentration of vesicles eluting continuously from the fractionator. These size and concentration data, gathered as a function of elution time, may be used to construct both number- and mass-weighted vesicle size distributions. Unlike most competing, noninvasive methods, this flow FFF/MALLS technique enables measurement of vesicle size distributions without a separate refractive index detector, calibration using particle size standards, or prior assumptions about the shape of the size distribution. Experimentally measured size distributions of vesicles formed by extrusion and detergent removal are non-Gaussian and are fit well by the Weibull distribution. Flow FFF/MALLS reveals that both the extrusion and detergent dialysis vesicle formation methods can yield nearly size monodisperse populations with standard deviations of approximately 8% about the mean diameter. In contrast to the rather low resolution of dynamic light scattering in analyzing bimodal systems, flow FFF/MALLS is shown to resolve vesicle subpopulations that differ by much less than a factor of two in mean size.

I. Study of protein aggregation due to heat denaturation: A structural approach using circular dichroism spectroscopy, nuclear magnetic resonance, and static light scattering.

The objective of this study was to investigate the relationship between oxidized RNase A protein structure and the occurrence of protein aggregation using several spectroscopic techniques. Circular dichroism spectroscopy (CD) measurements taken at small temperature intervals were used to determine the protein's melting temperature, Tm, of approximately 65 degrees C in deionized water. A more detailed examination of the protein structure was undertaken at several temperatures around Tm using near- and far-UV CD and one-dimensional nuclear magnetic resonance (NMR) measurements. These measurements revealed the presence of folded structures at 55 degrees C and below, while denatured structures appeared at 65 degrees C and above. Concurrent static light scattering (SLS) measurements, employed to detect the presence of RNase A aggregates, showed that RNase A aggregation was observed at 65 degrees C and above, when much of the protein was denatured. Subsequent NMR time-course data demonstrated that aggregates forming at 75 degrees C and pH 7.8 were indeed derived from heat-denatured protein. However, aggregation was also detected at 55 degrees C when the spectroscopic data suggested the protein was present predominantly in the folded configuration. In contrast, heat denaturation did not lead to RNase A aggregation in a very acidic environment. We attribute this phenomenon to the effect of charge-charge repulsion between the highly protonated RNase A molecules in very acidic pH.

II. Electrostatic effect in the aggregation of heat-denatured RNase A and implications for protein additive design.

In the previous study (part I), heat-denatured RNase A aggregation was shown to depend on the solution pH. Interestingly, at pH 3.0, the protein did not aggregate even when exposed to 75 degrees C for 24 h. In this study, electrostatic repulsion was shown to be responsible for the absence of aggregates at that pH. While RNase A aggregation was prevented at the extremely acidic pH, this is not an environment conducive to maintaining protein function in general. Therefore, attempts were made to confer electrostatic repulsion near neutral pH. In this study, heat-denatured RNase A was mixed with charged polymers at pH 7.8 in an attempt to provide the protein with excess surface cations or anions. At 75 degrees C, SDS and dextran sulfate were successful in preventing RNase A aggregation, whereas their cationic, nonionic, and zwitterionic analogs did not do so. We believe that the SO3- groups present in both additives transformed the protein into polyanionic species, and this may have provided a sufficient level of electrostatic repulsion at pH 7.8 and 75 degrees C to prevent aggregation from proceeding.

Proliferative T cell responses to four human cytomegalovirus-specific proteins in healthy subjects and solid organ transplant recipients.

It is still poorly understood which of the cytomegalovirus (CMV)-induced proteins are important for the host's cellular immunity during active infection and for establishing latency. To answer this question, in vitro proliferative T cell responses to four recombinant CMV proteins were compared and compared with responses to CMV-infected fibroblasts in immunocompetent healthy CMV-seropositive subjects and immunocompromised organ transplant recipients. The proteins studied were the lower matrix protein pp65 (ppUL83), the DNA-binding protein p52 (ppUL44), and the two immediate-early proteins IE1 (UL123) and IE2 (UL122). In healthy persons, pp65 was the most important protein with respect to its ability to induce a proliferative T cell response. In transplant recipients, severe suppression of the responses to these CMV proteins was found. This finding may be clinically relevant in view of the occurrence and course of CMV infection in these patients.

Comparative immunoblot analysis with ten different, partially overlapping recombinant fusion proteins derived from five different cytomegalovirus proteins.

Ten fusion proteins derived from five various CMV encoded proteins were used for the detection of specific antibody response by immunoblot technique in sera from renal transplant recipients. The fusion proteins were derived from the following CMV specific proteins: the assembly protein ppUL80a with an apparent molecular weight of 38 kD, ppUL99 (MW of 28 kD), the basic phosphoprotein ppUL32 (MW of 150 kD), the lower matrix protein ppUL83 (65 kD), and the DNA binding protein ppUL44 (MW of 52 kD). Some fragments overlapped and responses to these recombinant proteins were compared. Antibody responses appeared to be predominately directed at fusion proteins of ppUL32, the basic phosphoprotein and at ppUL44, the major DNA binding protein. Some differences were found in the responses to these partly overlapping fusion proteins. In addition, an IgM response mainly present in primary infections to fusion proteins XP1 and G2, again representing ppUL32 and ppUL44, was found.

Humoral immune response against human cytomegalovirus (HCMV)-specific proteins after HCMV infection in lung transplantation as detected with recombinant and naturally occurring proteins.

The humoral immune response to four intracellularly located cytomegalovirus (CMV) proteins was studied in 15 lung transplant recipients experiencing active CMV infections. Five patients had primary infections, and 10 had secondary infections. Antibodies of the immunoglobulin M (IgM) and IgG classes were measured in an enzyme-linked immunosorbent assay (ELISA) system in which procaryotically expressed recombinant proteins were used as a substrate and also in a monoclonal antibody-based capture ELISA which uses naturally occurring proteins as a substrate. The proteins investigated were the lower matrix protein pp65 (ppUL83), the major DNA-binding protein p52 (ppUL44), and the two immediate early proteins IE1 and IE2 (different splicing products of UL123). Higher levels of antibodies were found to pp65 and especially to p52 than to the immediate early antigens. Antibody levels detected in the recombinant protein-based ELISAs were generally lower than antibody responses detected with the matching antigen capture ELISA. Moreover, some patients appeared to have antibodies mainly to epitopes present on naturally occurring proteins. The antibody responses detected in both assays were related to the viral load during infection as assessed by the CMV antigenemia test, which is a quantitative marker for CMV load. It was found that although epitopes on naturally occurring proteins induce higher antibody responses and responses in more patients, antibodies directed to epitopes present on the recombinant proteins were inversely related to the viral load during a CMV infection. Therefore, antibodies to epitopes on the recombinant proteins might be more clinically relevant in this group of lung transplant recipients.