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ID PMID Title PublicationDate abstract
20563618 Report of 12 cases of ankylosing spondylitis patients treated with Tripterygium wilfordii. 2010 Sep OBJECTIVE: Description of the clinical response of 12 consecutive cases of disease-active ankylosing spondylitis (AS) treated with the herbal medicine Tripterygium wilfordii Hook f (TwHf; lei gong teng, thunder god vine), which has been reported in controlled studies to be effective in rheumatoid arthritis (RA). METHODS: The clinical status of 12 patients with active AS who were started on 60 mgday(-1) of a commercial tablet preparation of TwHf extract. were monitored at weeks 1, 3, and 6. RESULTS: Compared to baseline, there was significant improvement in mean values of physician assessment, Bath ankylosing spondylitis disease activity index (BASDAI), Bath ankylosing spondylitis functional index (BASFI), and Bath ankylosing spondylitis global score (BAS-G) at weeks 3 and 6, with no changes in liver enzymes or complete blood count (CBC). CONCLUSION: A placebo-controlled double-blind study for Tripterygium is warranted. Until then, this particular report should be considered as case reports and not an endorsement of the use of Tripterygium in clinical practice.
20551958 Skin cancers associated with autoimmune conditions among elderly adults. 2010 Jun 29 BACKGROUND: Immunosuppression is a risk factor for certain skin cancers. Autoimmune conditions can involve the skin, and may involve immunosuppressive therapies. METHODS: We conducted a population-based case-control study among elderly US adults using Surveillance, Epidemiology, and End Results-Medicare-linked data of 44,613 skin cancer cases and 178,452 frequency-matched controls. Medicare claims identified autoimmune conditions. Adjusted odds ratios (ORs) compared prevalence in cases and controls. RESULTS: The most frequent autoimmune condition was rheumatoid arthritis (2.29%), which was associated with slightly increased risk of Merkel cell carcinoma (N=1977; OR (95%CI): 1.39 (1.10-1.74)). Risk of cutaneous non-Hodgkin's lymphoma (N=2652) was increased with psoriasis (OR (95%CI): 3.20 (2.62-3.92)). Risk of Kaposi's sarcoma (N=773) was elevated with ulcerative colitis (OR (95%CI): 2.76 (1.42-5.39)), and risk of other sarcomas (N=1324) was elevated with Graves disease (2.62 (1.30-5.31)). CONCLUSIONS: These findings suggest that immune disturbances in the skin, arising from autoimmune conditions or their treatment, promote development of skin cancer.
20551624 Coupling vascular and myocardial inflammatory injury into a common phenotype of cardiovasc 2011 The rising epidemic of cardiovascular (CV) disease is fuelled by obesity, hypertension and diabetes and, independently and cumulatively, by an aging population. Extensive research identified immunoinflammatory mechanisms as key drivers in the initiation and progression of the disease, from early asymptomatic stages of vascular and myocardial injury leading to the clinically manifest dysfunction and remodeling in advanced stages. Underlying processes include endothelial dysfunction and extracellular matrix restructuration leading to increased vascular stiffness, as well as myocardial remodeling with dilatation and wall thinning. In this, overproduction of tumor necrosis factor-α, amongst others, contributes to generalized CV injury and dysfunction. Moreover, recent insights into the involvement of innate and adaptive immunity in atherosclerosis have shed light on many interesting parallels with chronic systemic inflammatory conditions, such as rheumatoid arthritis, with aggravated inflammation-induced vascular and myocardial injury. Besides, chronologic age has been identified as a potent, independent risk for reduced CV capacity and a plethora of heart diseases, with other modifiable risk factors acting as accelerators. We discuss the available evidence and propose that characterization of inflammatory CV responses might reveal a distinctive CV inflammatory phenotype. A comprehensive noninvasive bio-signature, comprising immunomic biomarkers and integrated noninvasive imaging, may serve as a potential tool in the early diagnosis and prognostication of CV risk.
20502007 Targeting sphingosine 1-phosphate (S1P) levels and S1P receptor functions for therapeutic 2010 Sphingosine 1-phosphate (S1P) is an important regulator of many different immune functions including lymphocyte circulation, antigen presentation, and T cell development. It stimulates five G protein-coupled receptors designated S1P(1-5), which are also expressed by immune cells. S1P receptors couple to different heterotrimeric G proteins including G alpha i, q, and 12/13, and elicit cellular signalling events by activating the small GTPases Rac and Rho and protein kinases Akt, ERK, and JNK, and by inducing cellular calcium flux and inhibiting cAMP accumulation, amongst others. S1P is the exit signal for lymphocytes leaving lymphoid organs and present in blood and lymph at high nanomolar concentrations due to the S1P-producing activity of sphingosine kinases (SK). The S1P-degrading enzyme S1P-lyase maintains low amounts of S1P in lymphoid organs. Disrupting this concentration difference by S1P receptor agonists and antagonists like FTY720, SEW2871, and VPC23019, by an anti-S1P antibody, or by inhibiting the S1P-lyase has therapeutic potential for autoimmune diseases like multiple sclerosis (MS) and rheumatoid arthritis and for many other disorders like cancer, fibrosis, inflammation, macular degeneration, diabetic retinopathy, and glaucoma. This report aims to provide a brief overview of concepts, approaches, pharmaceutical compounds, and targets that are currently used to modulate S1P-driven immune functions.
20493895 The zebrafish as an in vivo model system for glucocorticoid resistance. 2010 Dec Glucocorticoids regulate a wide range of systems in vertebrate organisms, and their effects are mediated by the glucocorticoid receptor (GR). The responsiveness to glucocorticoids differs largely between individuals. Resistance to glucocorticoids is an important medical problem, since it limits the efficacy of glucocorticoids when they are used to treat immune-related diseases like asthma and rheumatoid arthritis. Glucocorticoid resistance also contributes to the pathogenesis of other diseases, like major depression because of the decreased negative feedback on the hypothalamic pituitary adrenal axis. In this review, we present the zebrafish as an excellent in vivo model system to study glucocorticoid resistance. First, the zebrafish is the only non-primate animal model in which a beta-isoform of GR occurs, which is a splice variant with dominant-negative activity. Zebrafish are easily genetically modified, so the expression of GRbeta can be varied, creating an in vivo model for GRbeta-induced glucocorticoid resistance. Second, by performing a forward-genetic screen using the glucocorticoid-induced decrease in POMC expression in the pituitary gland as a readout, several zebrafish mutants have been obtained which appear to be resistant to glucocorticoid treatment. We present here two types of in vivo models for studying glucocorticoid resistance, that will be used to study the molecular mechanism of glucocorticoid signaling and resistance. Finally these models will be used to screen for small molecules that can alleviate glucocorticoid resistance.
20399900 Modulation of inflammation by chondroitin sulfate. 2010 Jun OBJECTIVE AND METHODS: To evaluate the immune-modulator effect of chondroitin sulfate (CS) by means of the review of the literature. RESULTS: Inflammatory reactions are primarily originated by infectious agents, immune reactions and by sterile tissue lesions that activate membrane receptors by means of pathogen-associated molecular patterns, tissue breakdown products and cytokines. The activation of membrane receptors triggers the phosphorylation of mitogen activated protein kinases and of the nuclear factor kappaB (NF-kappaB). The binding of NF-kappaB to the promoter of target genes enhances the expression of pro-inflammatory cytokines, inducible nitric oxide synthase, cyclooxygenase 2, phospholipase A2, and matrix metalloproteases, proteins that contribute to tissue damage and to the inflammatory reaction. The activation of NF-kappaB has a key role in the immune homeostasis and the inflammatory response and therefore, in the pathogenesis of numerous diseases. Chondroitin sulfate (CS) is able to diminish NF-kappaB activation and nuclear translocation in chondrocytes and synovial membrane, effects that may explain the benefits of CS in osteoarthritis. In addition, systemic CS reduces NF-kappaB nuclear translocation in macrophages and hepatocytes, raising the hypothesis that CS might be of benefit to treat other diseases with a strong inflammatory component. There is preliminary evidence in humans that CS improves moderate to severe psoriasis. Moreover, experimental and clinical data suggest that CS might be a useful therapeutic agent in diseases such as inflammatory bowel diseases, atherosclerosis, Parkinson's and Alzheimer's diseases, multiple sclerosis, amyotrophic lateral sclerosis, rheumatoid arthritis and systemic lupus erythematosus. DISCUSSION: These results urge for double blinded placebo-controlled trials to confirm the utility of CS in diseases with immune and inflammatory components.
20350657 CD20 as a target for therapeutic type I and II monoclonal antibodies. 2010 Apr The last decade has seen the monoclonal antibody (mAb), rituximab, transform clinical management of many non-Hodgkin lymphomas and more recently provide new opportunities for controlling autoimmune conditions, such as rheumatoid arthritis. Although not yet fully determined, the explanation for this success appears to lie with the inherent properties of its target, CD20, which allow rituximab to recruit potent cytotoxic effectors with unusual efficiency. In this review we detail the properties of CD20 that make it such an effective therapeutic target and describe how different mAbs change the membrane distribution and internalization of CD20 and have distinct modes of cytotoxic activity.
20018019 Two-stage joint selection method to identify candidate markers from genome-wide associatio 2009 Dec 15 The interaction among multiple genes and environmental factors can affect an individual's susceptibility to disease. Some genes may not show strong marginal associations when they affect disease risk through interactions with other genes. As a result, these genes may not be identified by single-marker methods that are widely used in genome-wide association studies. To explore this possibility in real data, we carried out a two-stage model selection procedure of joint single-nucleotide polymorphism (SNP) analysis to detect genes associated with rheumatoid arthritis (RA) using Genetic Analysis Workshop 16 genome-wide association study data. In the first stage, the genetic markers were screened through an exhaustive two-dimensional search, through which promising SNP and SNP pairs were identified. Then, LASSO was used to choose putative SNPs from the candidates identified in the first stage. We then use the RA data collected by the Wellcome Trust Case Control Consortium to validate the putative genetic factors. Balancing computational load and statistical power, this method detects joint effects that may fail to emerge from single-marker analysis. Based on our proposed approach, we not only replicated the identification of important RA risk genes, but also found novel genes and their epistatic effects on RA. To our knowledge, this is the first two-dimensional scan based analysis for a real genome-wide association study.
19963349 Coordination of tolerogenic immune responses by the commensal microbiota. 2010 May All mammals are born ignorant to the existence of micro-organisms. Soon after birth, however, every mammal begins a lifelong association with a multitude of microbes that lay residence on the skin, mouth, vaginal mucosa and gastrointestinal (GI) tract. Approximately 500-1000 different species of microbes have highly evolved to occupy these bodily niches, with the highest density and diversity occurring within the intestine. These organisms play a vital role in mammalian nutrient breakdown and provide resistance to colonization by pathogenic micro-organisms. More recently, however, studies have demonstrated that the microbiota can have a profound and long-lasting effect on the development of our immune system both inside and outside the intestine. While our immune system has evolved to recognize and eradicate foreign entities, it tolerates the symbiotic micro-organisms of the intestine. How and why this tolerance occurs has remained unclear. Here we present evidence that the commensal microbes of the intestine actively induce tolerant responses from the host that coordinate healthy immune responses. Potentially, disruption of this dialogue between the host and microbe can lead to the development of autoimmune diseases such as inflammatory bowel disease (IBD), rheumatoid arthritis (RA), or Type I diabetes (TID). As a wealth of publications have focused on the impact of the microbiota on intestinal immune responses and IBD, this chapter will focus on the extra-intestinal impacts of the microbiota from development to disease and integrate the known mechanisms by which the microbiota is able to actively communicate with its host to promote health.
19963203 [Early surgery in patients with native valve endocarditis]. 2010 Feb Between January 1990 and December 2006, 93 patients with infective endocarditis on native valves were operated in the active phase of the disease. The average age of our patients was 32 years with a male ascendancy. The causal heart disorder was found in 89 % of the cases, dominated by rheumatoid arthritis. The germ in cause was isolated in 52.6 % of the cases. The operative indication was hemodynamic in 29 cases, infectious in nine cases, mixed in 29 cases and embolic in 26 cases. The average operating delay was of 13 days with regard to the beginning of the antibiotic treatment. We realized a valvular aortic replacement at 32 patients with reconstruction of the ring in six cases, a valvular mitral replacement at 29 patients, a mitroaortic replacement at 21 patients, a reconstructive mitral surgery in nine cases, a valvular tricuspid replacement in one case and a reconstructive tricuspid surgery in one case. The early mortality was 13 %. The follow-up was 89 % with an average recession of 3.1 years and a late mortality of 5 %. The aim of this study is to analyze the immediate and late results of the surgery of infective endocarditis in the active phase and to bring to light the prognostic factors of mortality.
19953004 Thiazolidinediones inhibit TNF-alpha-mediated osteoclast differentiation of RAW264.7 macro 2010 Jun TNF-alpha plays critical roles in bone-resorbing diseases, such as rheumatoid arthritis. Recent evidence suggests that thiazolidinediones (TZDs), which are peroxisome proliferator-activated receptor gamma agonists, have anti-inflammatory effects. The aim of this study was to evaluate the effect of TZDs on the TNF-alpha-mediated osteoclastogenesis of osteoclast precursor cells. TNF-alpha treatment of RAW264.7 murine macrophages or mouse bone marrow cells induced significant multinuclear osteoclast formation, and these differentiated osteoclast cells possessed bone-resorbing activity. The TZD drugs, rosiglitazone and pioglitazone, significantly inhibited TNF-alpha-induced osteoclast differentiation from both cell types and subsequent bone resorption. Reverse transcriptase-polymerase chain reaction, reporter gene assays, and Western blot results revealed that TZD treatment significantly suppressed NFATc1 expression. Moreover, GW9662 (a peroxisome proliferator-activated receptor gamma antagonist) prevented the inhibitory effect of TZDs on NFATc1 expression and osteoclast differentiation. In summary, our results demonstrate that TZDs inhibit TNF-alpha-mediated osteoclast differentiation by downregulation of NFATc1 expression. This observation increases the therapeutic applications of TZDs in inflammatory bone-resorbing diseases.
19906240 Clinical features associated with glucocorticoid receptor polymorphisms. An overview. 2009 Oct The glucocorticoid receptor (GR) is crucial for the effects of glucocorticoids (GCs). Several polymorphisms of the GR are associated with altered sensitivity to GCs. For the ER22/23EK polymorphism, a relative GC resistance has been demonstrated. In vivo, this was suggested by a smaller response to a dexamethasone suppression test (DST), whereas in vitro experiments showed a diminished transactivational activity. The associated features of ER22/23EK carriers consist of favorable metabolic and body compositional conditions. In elderly subjects this polymorphism was associated with longevity and decreased risk of dementia. Interestingly, recent studies also showed an increased risk of major depression. In contrast, the N363S polymorphism was reported to be associated with an enhanced sensitivity to GCs, as was demonstrated by a DST. This polymorphism has also been associated with increased body mass index (BMI) and LDL-cholesterol levels, as well as increased risk of cardiovascular disease. However, additional studies yielded conflicting results, showing no associations with being overweight. The BclI polymorphism is also associated with increased GC sensitivity. In addition, associations with increased abdominal fat mass, Crohn's disease and, remarkably, major depression have been reported. Another GR polymorphism, located in exon 9beta, is associated with increased expression and stabilization of the dominant negative splice variant GR-beta. Carriers of this polymorphism displayed a relative GC resistance in vitro as evidenced by diminished transrepressional activity, which is important for the immune system and inflammation. Associations have been found with increased inflammatory parameters, cardiovascular disease, and rheumatoid arthritis. In this article, studies concerning these clinically relevant GR variants are discussed.
19898558 S100A8/A9: a mediator of severe asthma pathogenesis and morbidity? 2009 Oct Nearly 12% of children and 6% of adults in Canada have been diagnosed with asthma. Although in most patients symptoms are controlled by inhaled steroids, a subpopulation (approximately 10%) characterized by excessive airway neutrophilia, is refractory to treatment; these patients exhibit severe disease, and account for more than 50% of asthma health care costs. These numbers underscore the need to better understand the biology of severe asthma and identify pro-asthma mediators released by cells, such as neutrophils, that are unresponsive to common steroid therapy. This review focuses on a unique protein complex consisting of S100A8 and S100A9. These subunits belong to the large Ca2+-binding S100 protein family and are some of the most abundant proteins in neutrophils and macrophages. S100A8/A9 is a damage-associated molecular pattern (DAMP) protein complex released in abundance in rheumatoid arthritis, inflammatory bowel disease, and cancer, but there are no definitive studies on its role in inflammation and obstructive airways disease. Two receptors for S100A8/A9, the multiligand receptor for advanced glycation end products (RAGE) and Toll-like receptor 4 (TLR4), are expressed in lung. TLR4 is linked with innate immunity that programs local airway inflammation, and RAGE participates in mediating fibroproliferative remodeling in idiopathic pulmonary fibrosis. S100A8/A9 can induce cell proliferation, or apoptosis, inflammation, collagen synthesis, and cell migration. We hypothesize that this capacity suggests S100A8/A9 could underpin chronic airway inflammation and airway remodeling in asthma by inducing effector responses of resident and infiltrating airway cells. This review highlights some key issues related to this hypothesis and provides a template for future research.
19892301 Prevention of strongyloides hyperinfection syndrome: a rheumatological point of view. 2009 Dec BACKGROUND: Strongyloides stercoralis (S.stercoralis) is a parasite that infects humans and in conditions of immunodeficiency may disseminate, causing the potentially fatal strongyloides hyperinfection syndrome (SHS). The aim of this review was to investigate the literature evidence on the prophylaxis of SHS in immunosuppressed patients with rheumatological disorders. MATERIAL AND METHODS: The MEDLINE database (from 1966 to 2008) was searched using the following terms: "strongyloidiasis", "disseminated strongyloidiasis", "Strongyloides stercoralis", "Strongyloides stercoralis dissemination", "strongyloides hyperinfection syndrome", "treatment", "prophylaxis", "prevention", "immunocompromised", "immunodepression", "immunosuppressed", "immunosuppression", "corticosteroids", "glucocorticoids", "lupus erythematosus", "rheumatoid arthritis", "rheumatic diseases". A search of the therapeutic studies using the same set of terms was carried out. RESULTS: No study on the prophylaxis of SHS restricted to rheumatic immunosuppressed patients was identified. However, two articles have been published on the prophylaxis of strongyloidiasis in other immunosuppressed patients. Additionally, 13 studies dealing with different therapeutical options for strongyloidiasis were identified and presented. CONCLUSIONS: Since there is no evidence on the prophylaxis of SHS in immunosuppressed rheumatic patients, the suggested regimen for that prophylaxis may rely on the results obtained from therapeutical studies. Ivermectin has the best safety profile, lower cost and best efficacy and should be the drug of choice for the prophylaxis of SHS in such patients. Although a definitive prophylactic regimen has not been defined, the option for 200 microg/kg/day for 2 days, repeated within 2 weeks, seems to be a reasonable approach. Such regimen should be repeated every 6 months in case of persisting immunosuppression in permanent residents of endemic areas.
19799026 [The comparison of the three anti-dsDNA antibody detecting test]. 2009 Feb OBJECTIVE: To compare the three Anti-dsDNA antibody detecting test (IIF, ELISA, Farr) with 200 serum samples to evaluate which one has higher sensitivity and specificity. METHODS: 200 serum samples including 120 serum samples of SLE, 20 serum samples of rheumatoid arthritis, 20 serum samples of MCTD, 20 serum samples of SS, 20 serum samples of PSS and 50 serum samples of healthy measured by IIF, Farr and ELISA. RESULTS: Detection the Anti-dsDNA antibody of the serum sample with the methods of IIF, ELISA and Farr. The positive percentage of Anti-dsDNA in SLE is 25%, 32% and 32%, while in RA is 0, 0 and 0; in PSS is 0, 0 and 5%; in SS is 0, 0 and 0; in healthy is 0, 0 and 0. CONCLUSION: Detection the Anti-dsDNA antibody with two method in the same time, especially with IIF and ELISA, will heighten the positive rate than with single method and will be helpful for the diagnosis of SLE.
19775099 Design, synthesis, biological evaluation, and NMR studies of a new series of arylsulfones 2009 Oct 22 Overexpression of macrophage elastase (MMP-12), a member of the matrix metalloproteinases family, can be linked to tissue remodeling and degradation in some inflammatory processes, such as chronic obstructive pulmonary disease (COPD), emphysema, rheumatoid arthritis (RA), and atherosclerosis. On this basis, MMP-12 can be considered an attractive target for studying selective inhibitors that are useful in the development of new therapies for COPD and other inflammatory diseases. We report herein the design, synthesis, and in vitro evaluation of a new series of compounds, possessing an arylsulfonyl scaffold, for their potential as selective inhibitors of MMP-12. The best compound in the series showed an IC50 value of 0.2 nM, with good selectivity over MMP-1 and MMP-14. A docking study was carried out on this compound in order to investigate its binding interactions with MMP-12, and NMR studies on the complex with the MMP-12 catalytic domain were able to validate the proposed binding mode.
19773191 Interferons and autoimmune disorders. 2009 Oct Interferons are ubiquitous cytokines produced by all mononuclear cell types in response to infection by a DNA or RNA virus. There are three major classes of interferons: type I or nonimmune interferons consist chiefly of interferons alpha produced by leukocytes and of interferon beta produced by fibroblasts, although there are several other less important variants; type II or immune interferon is interferon gamma, which is mainly produced by NK cells and T cells; and type III consists of the lambda interferons. Each type is characterized by a specific receptor and signal transduction pathway. Toll-like receptors (TLRs) on the cell membrane and endosomes recognize viruses and other microorganisms. Binding of DNA or RNA to endosomal TLRs generates a signal whose transduction pathways lead to molecules capable of binding to genes for various interferons, interleukin-1, and TNFalpha. Interferons can stimulate or inhibit up to 300 different genes encoding proteins involved in antiviral defense mechanisms, inflammation, adaptive immunity, angiogenesis, and other processes. The properties of interferons are used to treat a number of viral infections (e.g., hepatitis B and hepatitis C), inflammatory diseases (interferon beta for multiple sclerosis and interferon gamma for systemic sclerosis), and malignancies. Overactivation of the interferon pathways has been demonstrated in patients with systemic lupus erythematosus. The result is a characteristic pattern of mRNA expression known as the interferon signature. Interferon overactivation is related to inadequate clearance of apoptotic particles with accumulation of apoptosis products (DNA-CpG motifs and U-RNA). Similar abnormalities have been found in patients with primary Sjögren's syndrome, systemic sclerosis, and polymyositis, as well as in some cases of rheumatoid arthritis. Immunomodulation strategies designed to decrease interferon overactivity are being evaluated in patients with systemic lupus erythematosus.
19604125 Interleukin-1 beta targeted therapy for type 2 diabetes. 2009 Sep Since having been cloned in 1984, IL-1beta has been the subject of over 22,000 citations in Pubmed, among them over 800 reviews. This is because of its numerous effects. IL-1beta is a regulator of the body's inflammatory response and is produced after infection, injury, and antigenic challenge. It plays a role in various diseases, including autoimmune diseases such as rheumatoid arthritis, inflammatory bowel diseases and type 1 diabetes, as well as in diseases associated with metabolic syndrome such as atherosclerosis, chronic heart failure and type 2 diabetes. Macrophage are the primary source of IL-1, but epidermal, epithelial, lymphoid and vascular tissues also synthesize IL-1. IL-1beta production and secretion have also been reported from pancreatic islets. Insulin-producing beta-cells within pancreatic islets are specifically prone to IL-beta-induced destruction and loss of function. Macrophage-derived IL-1beta production in insulin-sensitive organs, leads to progression of inflammation and induction of insulin resistance in obesity. We summarize the mechanisms involved in inflammation and specifically the IL-1beta signals that lead to the progression of insulin resistance and diabetes. We highlight recent clinical studies and experiments in animals and isolated islets using IL-1beta as a potential target for the therapy of type 2 diabetes.
19601878 Platelet activating factor/platelet activating factor receptor pathway as a potential ther 2009 Jul Platelet activating factor (PAF) is a phospholipid mediator of inflammation that is released early in inflammation by a variety of cell types. PAF acts largely by binding to its receptor, PAF-R, a G-protein coupled receptor found on a variety of cells, including cells of the immune system. PAF has been implicated in the pathogenesis of asthma and allergic conditions, but its role in autoimmune conditions has been less extensively investigated. Here, we review the accumulating evidence for the role of PAF/PAF-R pathway in autoimmune diseases. We describe studies showing up-regulation of PAF-R in inflammatory bowel disease, rheumatoid arthritis and multiple sclerosis and review the evidence from the use of PAF-R antagonists. We describe results of experimental models of inflammatory diseases that point to a role for PAF/PAF-R pathway including those using PAF-R antagonists and those employing PAF-R knockout mice and knockout mice for cytosolic phospholipase2. Recent experiments from our laboratory show that PAF/PAF-R pathway may influence T cell responses and favour the Th17 phenotype (in which T cells produce tissue destructive proinflammatory cytokine IL-17). The PAF/PAF-R pathway is a promising target for pharmacological intervention in autoimmune diseases.
19582368 Stiffness in total knee arthroplasty. 2009 Sep Stiffness is a relatively uncommon complication after total knee arthroplasty. It has been defined as a painful limitation in the range of movement (ROM). Its pathogenesis is still unclear even if some risk factors have been identified. Patient-related conditions may be difficult to treat. Preoperative ROM is the most important risk factor, but an association with diabetes, reflex sympathetic dystrophy, and general pathologies such as juvenile rheumatoid arthritis and ankylosing spondylitis has been demonstrated. Moreover, previous surgery may be an additional cause of an ROM limitation. Postoperative factors include infections, arthrofibrosis, heterotrophic ossifications, and incorrect rehabilitation protocol. Infections represent a challenging problem for the orthopaedic surgeon, and treatment may require long periods of antibiotics administration. However, it is widely accepted that an aggressive rehabilitation protocol is mandatory for a proper ROM recovery and to avoid the onset of arthrofibrosis and heterotrophic ossifications. Finally, surgery-related factors represent the most common cause of stiffness; they include errors in soft-tissue balancing, component malpositioning, and incorrect component sizing. Although closed manipulation, arthroscopic and open arthrolysis have been proposed, they may lead to unpredictable results and incomplete ROM recovery. Revision surgery must be proposed in the case of well-documented surgical errors. These operations are technically demanding and may be associated with high risk of complications; therefore they should be accurately planned and properly performed.