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ID PMID Title PublicationDate abstract
22542476 Emerging roles for TNIP1 in regulating post-receptor signaling. 2012 Jun A vast number of cellular processes and signaling pathways are regulated by various receptors, ranging from transmembrane to nuclear receptors. These receptor-mediated processes are modulated by a diverse set of regulatory proteins. TNFα-induced protein 3-interacting protein 1 is such a protein that inhibits both transduction by transmembrane receptors, such as TNFα-receptor, EGF-R, and TLR, and nuclear receptors' PPAR and RAR activity. These receptors play key roles in regulating inflammation and inflammatory diseases. A growing number of references have implicated TNIP1 through GWAS and expression studies in chronic inflammatory diseases such as psoriasis and rheumatoid arthritis, although TNIP1s exact role has yet been determined. In this review, we aim to integrate the current knowledge of TNIP1s functions with the diseases in which it has been associated to potentially elucidate the role this regulator has in promoting or alleviating these inflammatory diseases.
22533994 Coexistence of lichen sclerosus and morphea: a retrospective analysis of 472 patients with 2012 Dec BACKGROUND: The coexistence of lichen sclerosus (LiS) and localized scleroderma (LoS) has sporadically been reported in the literature. Recently, a prospective multicenter study demonstrated a surprisingly high percentage of genital LiS in patients with morphea. OBJECTIVE: The aim of this study was to determine the prevalence of LiS in a cohort of patients with LoS who presented at a tertiary referral medical center for connective tissue diseases in Germany. METHODS: We retrospectively evaluated the prevalence of genital and extragenital LiS in adult and pediatric patients with different subtypes of LoS. Secondary outcome measures included demographic characteristics and prevalence of other concomitant autoimmune diseases. RESULTS: Of the 472 patients (381 adults, 91 children; mean age: 46 years; range, 4-88 years; female to male ratio: 3.5:1 in adults and 8:1 in children) with LoS, 27 (5.7%) also presented with LiS (19 extragenital and 8 genital lesions). LiS exclusively occurred in patients with plaque-type (morphea) and generalized LoS. Twenty-six of the 27 (96.2%) patients with concomitant LoS and LiS were adults. Compared with LiS in the general population, LiS was significantly more frequent in LoS as indicated by an odds ratio of 18.1 (95% confidence interval 2.6-134.2; P < .0001). In all, 38 (8.1%) patients with LoS had other autoimmune disorders (most frequently Hashimoto thyroiditis, rheumatoid arthritis, and alopecia areata). LIMITATIONS: This was a retrospective study. CONCLUSIONS: This large retrospective analysis confirms recent reports of a high prevalence of LiS in patients with LoS. Based on these findings, patients with LoS, especially those with morphea, should be carefully screened for concomitant LiS, including inspection of the anogenital region.
22475265 De-risking bio-therapeutics for possible drug interactions using cryopreserved human hepat 2012 Sep 1 Inflammatory diseases such as rheumatoid arthritis and psoriasis are characterized by increases in circulating cytokines, which play an important role in modulation of the disease state. Several marketed bio-therapeutics target cytokines and act as effective treatment strategies. Previous in-vitro and in-vivo studies have suggested that cytokines may have both direct and indirect effects on drug metabolizing enzyme levels in the liver. Few studies have characterized models to evaluate the risk of potential drug interactions that might be mediated by changes in cytokine levels. In the present studies the potential of three cytokines (IL-2, IL-6 and TNF-α) to modulate gene expression and activity of the major human cytochrome P450 (CYP) enzymes (CYP1A2, 2B6, 2C9, 2C19, 2D6, and 3A4) in cryopreserved human hepatocytes (CHH) was investigated. Significant decreases in the activity of all 6 CYP isoforms occurred in hepatocytes incubated with TNF-α or IL-6 (17-85%; and 22-76% of untreated control values, respectively). TNF-α down-regulated the gene expression of CYP1A2, 2D6 and 3A4 only, whereas IL-6 down-regulated gene expression of all of the tested CYP isoforms except 2D6. IL-2 had only mild effects on CYP activity and mRNA levels of examined isoforms. In CHH exposed to TNF-α, changes in CYP activity were not always paralleled by gene expression alterations for three of the examined CYP isoforms. These studies highlight several potential pitfalls in using isolated human hepatocytes for determination of drug interactions by bio-therapeutics including lack of correlation of mRNA and activity measurements for some CYP isoforms when using single time point determinations, and appropriateness of the model for indirect acting cytokine and cytokine modulators.
22427596 Prevalence of asymptomatic and symptomatic meibomian gland dysfunction in the general popu 2012 May 4 PURPOSE: To describe epidemiologic characteristics of asymptomatic and symptomatic meibomian gland dysfunction (MGD) in a general adult population in northwestern Spain. METHODS: A total of 1155 subjects aged 40 years and older were selected by an age-stratified random sample procedure in O Salnés, Spain. A standardized symptoms questionnaire was administered and a comprehensive ophthalmic evaluation, which included ocular surface tests, was carried out. Absent, viscous, or waxy white secretion upon digital expression, lid margin telangiectasia or plugging of the meibomian gland orifices was considered evidence of MGD. The prevalence and associations of asymptomatic and symptomatic MGD, and their effects on the ocular surface, were investigated. RESULTS: From 937 eligible subjects, 619 (66.1%) participated (mean age [SD], 63.4 [14.5] years; range, 40-96; 37.0% males). The prevalence of asymptomatic MGD was 21.9% (95% confidence interval [CI], 18.8-25.3). This prevalence increased with age (P = 0.000) and was higher in males than in females (P = 0.003). The prevalence of symptomatic MGD was 8.6% (95% CI, 6.7-10.9). This prevalence also increased with age (P = 0.000) but was not associated with sex. Abnormal tear breakup time and fluorescein staining prevalence estimates were higher among asymptomatic subjects. After controlling for age and sex, asymptomatic MGD was associated with diabetes (adjusted odds ratio [OR(a)] 2.23) and cardiovascular disease (OR(a) 1.80), and symptomatic MGD with rosacea (OR(a) 3.50) and rheumatoid arthritis (OR(a) 16.50). CONCLUSIONS: Asymptomatic MGD is more common than symptomatic MGD. Symptomatology is not associated with secondary damage to the ocular surface. Some systemic diseases may lower whereas others may raise the risk of developing symptoms. Symptom-based approaches do not seem appropriate for MGD estimation.
22387034 Deficiency of serum concentration of 25-hydroxyvitamin D in psoriatic patients: a case-con 2012 Nov BACKGROUND: Some autoimmune conditions have been associated with reduced vitamin D levels, including systemic lupus erythematosus, rheumatoid arthritis, diabetes mellitus, and multiple sclerosis. OBJECTIVE: The main objective of this study was to analyze the 25-hydroxyvitamin D (OHD) status of patients with psoriasis in comparison with control subjects without this disease. METHODS: This case-control study included 86 patients (43 with psoriasis and 43 age- and sex-matched control subjects) from the outpatient clinic of our hospital dermatology department in Granada, Spain. All patients and control subjects were studied during one 4-week period to avoid seasonal variations in vitamin D levels. RESULTS: Serum 25-OHD levels were significantly lower in psoriatic patients than in control subjects even after adjusting for confounding factors in a multivariate analysis (odds ratio 2.89, 95% confidence interval 1.02-7.64, P < .03 for vitamin D insufficiency). Low 25-OHD levels were negatively associated with C-reactive protein (inflammatory activation marker) and body mass index in multiple linear regression analysis. Psoriatic patients with body mass index greater than or equal to 27 kg/m(2) had a higher risk of 25-OHD insufficiency (sensitivity of 82.3% and specificity of 51.7%). LIMITATIONS: Further studies with larger numbers of patients are required to analyze the pathogenic mechanisms underlying the relationship between 25-OHD deficiency and psoriasis. CONCLUSIONS: The 25-OHD values are significantly lower in psoriatic patients than in control subjects. Low 25-OHD levels are negatively associated with C-reactive protein, an inflammatory activation marker, and with obesity. Psoriatic patients with a body mass index of 27 or more are likely to have vitamin D insufficiency.
22348323 Triptolide in the treatment of psoriasis and other immune-mediated inflammatory diseases. 2012 Sep Apart from cancer chronic (auto)immune-mediated diseases are a major threat for patients and a challenge for physicians. These conditions include classic autoimmune diseases like systemic lupus erythematosus, systemic sclerosis and dermatomyositis and also immune-mediated inflammatory diseases such as rheumatoid arthritis and psoriasis. Traditional therapies for these conditions include unspecific immunosuppressants including steroids and cyclophosphamide, more specific compounds such as ciclosporin or other drugs which are thought to act as immunomodulators (fumarates and intravenous immunoglobulins). With increasing knowledge about the underlying pathomechanisms of the diseases, targeted biologic therapies mainly consisting of anti-cytokine or anti-cytokine receptor agents have been developed. The latter have led to a substantial improvement of the induction of long term remission but drug costs are high and are not affordable in all countries. In China an extract of the herb Tripterygium wilfordii Hook F. (TwHF) is frequently used to treat autoimmune and/or inflammatory diseases due to its favourable cost-benefit ratio. Triptolide has turned out to be the active substance of TwHF extracts and has been shown to exert potent anti-inflammatory and immunosuppressive effects in vitro and in vivo. There is increasing evidence for an immunomodulatory and partly immunosuppressive mechanism of action of triptolide. Thus, compounds such as triptolide or triptolide derivatives may have the potential to be developed as a new class of drugs for these diseases. In this review we summarize the published knowledge regarding clinical use, pharmacokinetics and the possible mode of action of triptolide in the treatment of inflammatory diseases with a particular focus on psoriasis.
22313294 3D-QSAR of novel phosphodiesterase-4 inhibitors by genetic function approximation. 2011 Nov Phosphodiesterase-4 (PDE 4) enzyme has emerged as an invaluable target for the treatment of asthma, chronic obstructive pulmonary disease and rheumatoid arthritis. These findings have generated widespread interest in PDE-4 inhibitors as a potential molecular target for the development of new anti-inflammatory drugs. A series of N-substituted cis-tetra- and cis-hexahydrophthalazinone derivatives have been reported as novel, selective PDE-4 inhibitors with potent anti-inflammatory activity. In order to gain further insights into the structural requirements of novel series of N-substituted cis-tetra and cis-hexahydrophthalazinone derivatives as PDE-4 inhibitors, a three-dimensional quantitative structure activity relationship (3D-QSAR) was performed using Genetic Function Approximation (GFA). The QSAR model was generated using a training set of 45 molecules and the predictive ability of the resulting each model was assessed using a test set of 9 molecules. The internal and external consistency of final QSAR model was 0.675 and 0.750 respectively. Analysis of results from the present QSAR study indicates that shape and structural descriptors strongly govern the PDE-4 enzyme inhibitory activity. This QSAR study highlights the structural features required for PDE-4 enzyme inhibition and may be useful for design of potent PDE-4 inhibitors.
22267327 Fibrinogen and factor XIII A-subunit genotypes interactively influence C-reactive protein 2012 Jul OBJECTIVE: Fibrinogen is a target of autoimmune reactions in rheumatoid arthritis (RA). Fibrin(ogen) derivatives are involved in inflammatory processes and the generation of a stable fibrin network is necessary for sufficient inflammation control. As the density and stability of fibrin networks depend on complex interactions between factor XIIIA (F13A) and fibrinogen genotypes, the authors studied whether these genotypes were related to C-reactive protein (CRP) levels during acute-phase reactions. METHODS: Association between α-fibrinogen (FGA), β-fibrinogen (FGB) and F13A genotypes with CRP levels was tested in two cohorts with longitudinal CRP measurements. Discovery and replication cohorts consisted of 288 RA (913 observations) and 636 non-RA patients (2541 observations), respectively. RESULTS: Genotype FGB -455G>A (rs1800790) was associated with CRP elevations (≥ 10 mg/l) in both cohorts (RA, OR per allele 0.69, p=0.0007/P(adj)<0.015; non-RA, OR 0.70, p=0.0004/p(adj)<0.02; combined, OR 0.69, p<10(-5)/p(adj)=0.001). Genotype F13A 34VV (rs5985) was conditional for the association of FGB -455G>A with CRP as indicated by a clear restriction on F13A 34VV individuals and a highly significant heterogeneity between F13A 34VV and F13A 34L genotypes (p<10(-5), p(adj)=0.001). In both cohorts, mean CRP levels significantly declined with ascending numbers of FGB -455A alleles. Genotype FGA T312A (rs6050) exhibited opposite effects on CRP compared with FGB -455G>A. Again, this relation was dependent on F13A V34L genotype. CONCLUSION: Novel genetic determinants of CRP completely unrelated to previously known CRP regulators were identified. Presumably, these haemostatic gene variants modulate inflammation by influencing fibrin crosslinking. These findings could give new perspectives on the genetic background of inflammation control.
22065367 Increased expression of the histamine H4 receptor subtype in hypertrophic differentiation 2012 Mar Histamine has been regarded as an inflammatory mediator of arthritic disorders. We have previously reported that the expression of histamine H(4) receptor (H(4)R) mRNA in synovial tissues was significantly higher in patients with osteoarthritis (OA) compared to those with rheumatoid arthritis. Chondrocyte hypertrophy and endochondral ossification are essential processes in pathologic disorders such as osteophyte formation during OA progression. In the present study, we examined the expression of H(4) R during differentiation into hypertrophic chondrocytes in the ATDC5 cells, a widely used in vitro model of chondrogenic differentiation. Quantitative reverse transcription polymerase chain reaction showed that the levels of histidine decarboxylase and H(4)R mRNA on ATDC5 cells were increased in a time-dependent manner during the culture period. By contrast, the expressions of H(1)R and H(2)R were not increased from day 7 onwards. The mRNA expression of the hypertrophic chondrocyte marker type X collagen (COL X) was increased markedly from 14 to 21. Immunocytochemical analysis indicated that H(4)R staining was strongly immunoreactive on the plasma membrane of ATDC5 cells. Flow cytometry showed increased expression of H(4)R and COL X protein in ATDC5 chondrocytes. Furthermore, the majority of the COL X-positive cells expressed H(4) R throughout the culture period. In summary, we showed for the first time that H(4)R is expressed in ATDC5 chondrocytes. Moreover, we found that most hypertrophic chondrocytes express H(4)R, suggesting that this receptor might be associated with the differentiation of chondrocytes into hypertrophic cells, which are abnormally observed in joint lesions in OA.
20013270 Non-Hodgkin's lymphoma following treatment with etanercept in ankylosing spondylitis. 2011 Dec Anti-TNF drugs may increase lymphoma risk in autoimmune rheumatic diseases, such as rheumatoid arthritis, but there have been no reports stating increased risk of lymphoma in ankylosing spondylitis (AS). Before 2 years, we had presented a case with AS developing Hodgkin's lymphoma following 6 months of etanercept treatment. Hereby, we present another case with AS developing non-Hodgkin's lymphoma (NHL), subsequent to 11 months of etanercept treatment. Pathological analysis revealed diffuse large B cell NHL. Although this is a report of a single case, cautious use of anti-TNF drugs is strongly recommended as they might cause lymphoma development even in AS.
19967775 Estrogen receptor β ligands: recent advances and biomedical applications. 2011 May Recent work elucidating the role that the estrogen receptor β (ERβ), a member of the nuclear receptor superfamily, plays in regulating various physiological functions has highlighted the potential of this receptor subtype as a therapeutic target for several pathologies. In fact, molecules that are able to selectively activate ERβ hold promise for the treatment of certain cancers, as well as endometriosis, inflammatory diseases including rheumatoid arthritis, and cardiovascular and CNS conditions. Nevertheless, ERβ remains a challenging target because its ligand-binding cavity is very similar to that present in ERα, and this makes it difficult to develop ligands having sufficient levels of ERβ selectivity for therapeutic use. Nevertheless, considerable advances have recently been made in developing both nonsteroidal and steroidal ERβ-selective agonists. These molecules constitute not only important tools to probe the biological effects of the selective stimulation of ERβ, but some of them appear to be agents with considerable therapeutic potential. This study provides a detailed review of selective ERβ ligands that have been developed recently. After a brief introduction to the structure and nature of the two ERs and the biology of ERβ and its isoforms, the ligands are classified on the basis of their structures and activities. Common pharmacophore elements are highlighted throughout the description of the various chemical classes analyzed, and these elements are presented in a concluding summary overview along with a discussion of potential therapeutic applications of these agents in biomedicine.
23264357 Serum soluble interleukin 7 receptor is strongly associated with lupus nephritis in patien 2013 Mar BACKGROUND: The soluble form of the interleukin 7 receptor (sIL-7R) is produced by fibroblasts after stimulation with proinflammatory cytokines. Increased sIL-7R serum and synovial fluid levels were recently demonstrated in patients with rheumatoid arthritis. OBJECTIVES: To investigate whether sIL-7R production is dysregulated in systemic lupus erythematosus (SLE), and whether this correlates with disease activity. METHODS: Serum and urine sIL-7R concentrations were measured by ELISA, and sIL-7R quantitative PCR (qPCR) studies were performed in peripheral blood mononuclear cells (PBMCs). IL-7R, tumour necrosis factor α (TNFα), IL-1β and IL-17 immunostainings were performed on kidney sections. RESULTS: sIL-7R concentrations were significantly higher in SLE sera than in controls, and correlated with SLE Disease Activity Index (SLEDAI) scores. Accordingly, serum sIL-7R levels were strongly raised in patients with nephritis. Moreover in patients with lupus nephritis, serum sIL-7R decreased upon treatment. sIL-7R gene expression in PBMCs was similar in patients with lupus nephritis and controls. By contrast, abundant perivascular IL-7R expression was seen in SLE kidney biopsy specimens, which was associated with expression of TNFα in the surrounding tissue. CONCLUSIONS: Our data indicate that sIL-7R is a marker of SLE disease activity, especially nephritis. In contrast to conventional disease activity markers, sIL-7R is not produced by immune cells, but might instead reflect activation of tissue cells in the target organ.
23122347 Impact of socioeconomic status on ionizing radiation exposure from medical imaging in chil 2012 Nov PURPOSE: To characterize cumulative radiation exposure from diagnostic imaging (CEDI) in pediatric patients and to investigate its relationship to patients' socioeconomic status and comorbid medical conditions. METHODS: A retrospective cohort study of >19,000 pediatric patients seen within the outpatient clinic system of an academic tertiary care urban medical center during the month of January 2006 was conducted to estimate CEDI from all procedures performed within 3 years of the index visit (until January 2009). Socioeconomic status was estimated from census tract geocoding. Comorbid medical conditions were identified from the electronic medical record. RESULTS: A total of 19,063 patients underwent imaging tests within the index month. The mean age was 8.9 ± 6.3 years. Most had private insurance (56%), with 36% receiving Medicaid and 8% private payers. Our population lived in census tracts in which 27 ± 16% of the population were below the federal poverty level with 62% living in areas in which 20% of residents were living below the poverty level. There were differences in CEDI (P < .0001) by age, insurance type, and percentage poverty in the census tract of residence but not among racial groups (P = .6508). The association between poverty and CEDI was generally explained by the 26 Elixhauser diagnoses, with the exception of rheumatoid arthritis. CONCLUSION: Patients living in areas of greater poverty were exposed over time to more radiation from diagnostic testing than those living in areas with lower percentages of residents living in poverty. This association was explained almost entirely by the presence of disease burden. No direct association was found between socioeconomic status and CEDI.
23115803 (64)Cu-Labeled DOTA-conjugated rituximab, a chimeric murine/human anti-CD20 monoclonal ant 2004 Rituximab is a chimeric murine/human monoclonal antibody (mAb) that targets the CD20 antigen (also known as membrane-spanning 4-domains, subfamily A, member 1, or MS4A1) and has been approved by the United States Food and Drug Administration for the treatment of non-Hodgkins lymphomas (NHL; diffused large-B cell, low-grade, or follicular types), rheumatoid arthritis, granulomatosis with polyangiitis (Wegener's granulomatosis) and microscopic polyangiitis. The exact mechanism of action of rituximab has been discussed by Maloney (1). Although much is known about the pathogenesis of the different forms of NHL at the molecular level, the prognosis for an individual suffering from this disease is based on the morphological and histological information obtained with invasive methods used on the patients (2). Therefore, the use of noninvasive procedures, such as imaging with radiolabeled agents, is an attractive option to screen for patients who can benefit the most from an anti-cancer treatment, and the same imaging technique(s) can be used to monitor and assess the efficacy of a treatment (3). In the clinic, positron emission tomography (PET) is commonly used to detect, stage, and monitor the treatment outcome for various cancers because this imaging modality has superior penetration and sensitivity and it is more quantitative compared with other imaging techniques such as single-photon emission computed tomography, magnetic resonance imaging, ultrasound, and optical imaging (4). In this regard, there is much effort devoted to the development of radiolabeled mAbs that can be used with PET for the targeted imaging of neoplasms that express specific antigens, such as the epidermal growth factor receptor (5) and the carcinoembryonic antigen (6). (64)Cu-Labeled rituximab ([(64)Cu]-DOTA-rituximab) was developed in an effort to generate a PET imaging agent that can be used to monitor the treatment of NHL (2). The biodistribution of [(64)Cu]-DOTA-rituximab was studied with PET in huCD20 transgenic mice, which mimic the human B-cell lymphoma tumors (obtained from Genentech Corporation, CA) (2).
22973890 Effects of a self-care promoting problem-based learning programme in people with rheumatic 2013 Jul AIM: To evaluate the effects of a self-care promoting problem-based learning programme for people with rheumatic diseases in terms of health-related quality of life, empowerment, and self-care ability. BACKGROUND: Individuals with rheumatoid arthritis express a great need for education and support in adapting to the disease, but the average qualities of studies about patient education interventions are not high. There is no evidence of long-term benefits of patient education. DESIGN: Randomized controlled trial. METHODS: A randomized controlled design was selected with test at baseline, 1-week and 6-month post-interventions after completed the 1-year programme. The tests consisted of validity and reliability tested instruments. The participants were randomly assigned in spring 2009 to either the experimental group (n = 54) or the control group (n = 148). The programme was running alongside the standard care the participants received at a rheumatology unit. Parametric and non-parametric tests were used in the analyses. RESULTS: The participants in the experimental group had statistically significant stronger empowerment after participation in the self-care promoting problem-based learning programme compared with the control group, at the 6-month post-intervention. Approximately, two-thirds of the participants in the experimental group stated that they had implemented lifestyle changes due to the programme. CONCLUSION: The self-care promoting problem-based learning programme enabled people with rheumatic diseases to improve their empowerment compared with the control group. It is important to continue to develop problem-based learning in patient education to find the very best way to use this pedagogical method in rheumatology care.
22919406 Rituximab-based treatment, HCV replication, and hepatic flares. 2012 Rituximab, a chimeric mouse-human monoclonal antibody directed to the CD20 antigen expressed on pre-B lymphocytes and mature lymphocytes, causes a profound B-cell depletion. Due to its peculiar characteristics, this drug has been used to treat oncohaematological diseases, B cell-related autoimmune diseases, rheumatoid arthritis, and, more recently, HCV-associated mixed cryoglobulinaemic vasculitis. Rituximab-based treatment, however, may induce an increased replication of several viruses such as hepatitis B virus, cytomegalovirus, varicella-zoster virus, echovirus, and parvovirus B19. Recent data suggest that rituximab-based chemotherapy induces an increase in HCV expression in hepatic cells, which may become a target for a cell-mediated immune reaction after the withdrawal of treatment and the restoration of the immune control. Only a few small studies have investigated the occurrence of HCV reactivation and an associated hepatic flare in patients with oncohaematological diseases receiving R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone). These studies suggest that the hepatic flares are frequently asymptomatic, but life-threatening liver failure occurs in nearly 10% of cases.
22806469 Altered posttranslational modification on U1 small nuclear ribonucleoprotein 68k in system 2012 Jul Anti-ribonucleoprotein (anti-RNP) antibodies are one of the representative autoantibodies detectable in patients with systemic lupus erythematosus (SLE) and mixed connective tissue disease (MCTD). Generally, posttranslational modifications (PTMs) on autoantigens are proposed to be involved in the production of autoantibodies. In this study, we tried to detect the alteration in PTMs on a U1 small nuclear RNP 68k subunit (U1-68k), a major antigen of anti-RNP antibodies. Peripheral blood mononuclear cells (PBMCs) were obtained from patients with MCTD, SLE, and rheumatoid arthritis (RA), and from healthy donors. U1-68ks in the PBMCs were detected by 2D Western blot (WB), where extracted nuclear proteins were separated by 2DE, followed by the detection of U1-68k using WB. More than 20 PTM isoforms were detected with different molecular weights of 65.0 , 66.5, and 68.0kDa, and different pIs between 6.0 and 8.5. Importantly, the relative intensity of the spot with 66.5 kDa and pI 7.5 was significantly increased in the MCTD and SLE groups compared to the RA and healthy groups. Further, this U1-68k isoform, in particular, in its RS domain, was found to have significantly decreased phosphorylation compared to the other isoforms. The PTM alternation may be one of the steps to generate the anti-RNP antibodies.
22741783 Synthesis and immunomodulation of human lymphocyte proliferation and cytokine (interferon- 2012 Sep Leflunomide is an immunomodulating drug that has been used clinically for the treatment of rheumatoid arthritis and other immune system disorders. As a continuation of our previous work, four novel analogues of leflunomide (6a, 6b, 7a and 7b) were synthesized; here, an imidazolyl group has replaced the isoxazolyl moiety, while the 4-trifluoromethylphenyl group has been retained. These analogues were synthesized and investigated in vitro for their immunomodulating activity by examining human lymphocyte proliferation and determining the cytokine interferon-γ concentrations in human lymphocyte cells. For this purpose, 5 x 10(4) human lymphocyte cells were incubated at 37°C in 5% CO(2) with phytohemagglutinin and one of the analogues (concentrations ranging from 1 to 100 mM), negative controls or cyclosporine (0.1 mM). The compounds' effects on lymphocyte proliferation and interferon-γ (IFN-γ) production were determined using an MTT assay and an ELISA, respectively. All compounds were found to have significant effects on both lymphocyte proliferation and IFN-γ production in comparison to the negative control. However, the compounds' effects were weaker than those of the positive control. Some differences among compounds 6a, 6b, 7a and 7b were seen on lymphocyte proliferation and cytokine production. Compound 6a (R=CH(3) containing a trifluoromethylaniline moiety) suppressed lymphocyte proliferation and IFN-γ production with a potency comparable to the positive control. Therefore, further studies to evaluate the compound's effects in clinical conditions are suggested.
22688774 Application of quartz crystal microbalance with dissipation monitoring technology for stud 2012 Poxviruses are one of the most complex of animal viruses and encode for over 150 proteins. The interactions of many of the poxviral-encoded proteins with host proteins, as well as with other proteins, such as transcription complexes, have been well characterized at the qualitative level. Some have also been characterized quantitatively by two hybrid systems and surface plasmon resonance approaches. Presented here is an alternative approach that can enable the understanding of complex interactions with multiple ligands. The example given is that of vaccinia virus complement control protein (VCP). The complement system forms the first line of defense against microorganisms and a failure to appropriately regulate it is implicated in many inflammatory disorders, such as traumatic brain injury, Alzheimer's disease (AD), and rheumatoid arthritis. The complement component C3 is central to the complement activation. Complement regulatory proteins, capable of binding to the central complement component C3, may therefore effectively be employed for the treatment and prevention of these disorders. There are many biochemical and/or immunoassays available to study the interaction of proteins with complement components. However, protocols for many of them are time consuming, and not all assays are useful for multiple screening. In addition, most of these assays may not give information regarding the nature of binding, the number of molecules interacting with the complement component C3, as well as kinetics of binding. Some of the assays may require labeling which may induce changes in protein confirmation. We report a protocol for an assay based on quartz crystal microbalance with dissipation monitoring (QCM-D) technology, which can effectively be employed to study poxviral proteins for their ability to interact with their ligand. A protocol was developed in our laboratories to study the interaction of VCP with the complement component C3 using Q-sense (D-300), equipment based on QCM-D technology. The protocol can also be used as a prototype for studying both proteins and small-sized compounds (for use as anti-poxvirals) for their ability to interact with and/or inhibit the activity of their ligands.
22533488 The potential role of synovial thrombomodulin in the pathophysiology of joint bleeds in ha 2012 Sep Haemophilic arthropathy (HA) is one of the main complications of recurrent bleeding episodes in patients with severe haemophilia. However, the precise reasons making joints the predilected site of bleeding in patients with haemophilia are not fully understood. The objective of this project was to study the potential effect of synovium-derived thrombomodulin (TM) on the pathophysiology of haemarthroses. The concentration of TM and tissue factor pathway inhibitor (TFPI) was measured in knee synovial fluid of patients with haemophilia and controls. We used these concentrations of TM and TFPI in a thrombin generation (TG) model to analyse their in vitro effects on coagulation in plasma of six male controls and six severe haemophiliacs. The expression of TM in synovial tissue was also studied in controls and haemophiliacs. Patients with HA had significantly higher synovial fluid TFPI and TM levels, with a mean of 47 ± 27 ng/mL (P = 0.033) and 56 ± 25 ng/mL (P = 0.031), respectively, compared to the control group which presented lower levels of synovial fluid TFPI (26 ± 9 ng/mL) and TM concentrations (39 ± 21 ng/mL). TG capacity was significantly reduced in the presence of TM 56 ng/mL (P = 0.02), concentration observed in the synovial fluid of patients with HA. The concomitant addition of TM 56 ng/mL and TFPI 47 ng/mL induced a highly significant inhibition of TG in the same samples (P = 0.008).No significant inhibition of TG capacity was observed in the presence of control synovial concentration of TM (P > 0.05). Our results showed increased TM levels in synovial fluid and dramatically impaired expression of TM on synovial cells, suggesting a massive release of TM into the synovial fluid induced by a concerted action of neutrophils and cytokines on synovial cells as previously described in patients with rheumatoid arthritis.