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ID PMID Title PublicationDate abstract
20871631 A transforming Src mutant increases the bioavailability of EGFR ligands via stimulation of 2011 Feb 3 ADAM17 (a disintegrin and metalloproteinase 17, also referred to as TNFα converting enzyme or TACE) is a cell-surface metalloproteinase that regulates signaling via the epidermal growth factor receptor (EGFR) and has important roles in diseases such as cancer and rheumatoid arthritis. ADAM17 can be activated by stimulation of several tyrosine kinase receptors, raising questions about whether oncogenic tyrosine kinases could also enhance EGFR signaling and activation of extracellular signal-regulated kinase (ERK) via stimulation of ADAM17. The main goal of this study was to evaluate the role of Src in activating ADAM17. We provide evidence that a constitutively active transforming form of Src, the E378G mutant, as well as v-Src enhance ADAM17-mediated shedding of the EGFR ligand TGFα. Moreover, we demonstrate that constitutive shedding of TGFα can be reduced by inhibition of Src in several cell lines, including COS7, MCF7 (the human breast cancer cell line), PAE (a pig aortic endothelial cell line) and HaCaT (the human keratinocyte cell line) cells. Src(E378G)-stimulated shedding of TGFα is abolished in Adam17(-/-) cells, but can be rescued by wild-type (wt) ADAM17 and a mutant ADAM17 lacking its cytoplasmic domain. These findings demonstrate that ADAM17 is the principal TGFα sheddase that is activated by Src in a manner that does not require the cytoplasmic domain of ADAM17. Finally, we show that stimulation of ADAM17 by Src(E378G) leads to enhanced paracrine signaling via release of EGFR ligands into the culture supernatant. These results raise the possibility that activation of ADAM17 by oncogenic forms of Src can aid in promoting tumorigenesis by enhancing signaling via the EGFR and ERK in an autocrine and paracrine manner. Enhanced autocrine signaling could further activate tumor cells expressing oncogenic mutants of Src, whereas paracrine signaling could stimulate EGFR and ERK signaling in surrounding non-transformed cells such as stromal cells, thereby contributing to crosstalk between tumor cells and stromal cells.
20392289 Genetic associations in type I interferon related pathways with autoimmunity. 2010 Type I interferons play an outstanding role in innate and adaptive immunity by enhancing functions of dendritic cells, inducing differentiation of monocytes, promoting immunoglobulin class switching in B cells and stimulating effector functions of T cells. The increased production of IFNα/β by plasmacytoid dendritic cells could be responsible for not only efficient antiviral defence, but it also may be a pathological factor in the development of various autoimmune disorders. The first evidence of a genetic link between type I interferons and autoimmune diseases was the observation that elevated IFNα activity is frequently detected in the sera of patients with systemic lupus erythematosus, and that this trait shows high heritability and familial aggregation in their first-degree healthy relatives. To date, a number of genes involved in interferon signalling have been associated with various autoimmune diseases. Patients with systemic lupus erythematosus, Sjögren's syndrome, dermatomyositis, psoriasis, and a fraction of patients with rheumatoid arthritis display a specific expression pattern of interferon-dependent genes in their leukocytes, termed the interferon signature. Here, in an attempt to understand the role of type I interferons in the pathogenesis of autoimmunity, we review the recent advances in the genetics of autoimmune diseases focusing on the association of genes involved in type I interferon pathways.
19950109 MDR1a/1b gene silencing enhances drug sensitivity in rat fibroblast-like synoviocytes. 2010 Feb BACKGROUND: Drug resistance mediated by P-glycoprotein (P-gp) is one of the major reasons for the failure of rheumatoid arthritis (RA) therapy with disease modifying anti-rheumatic drugs and glucocorticoids. In the present study, we aimed to investigate the in vitro effectiveness of small interfering RNA (siRNA) to render rat fibroblast-like synoviocytes (FLS) susceptible to drugs. We also attempted the electroporation-mediated transfer of siRNA against multidrug resistance (MDR) genes into rat knee joints. METHODS: FLS were transfected with siRNAs corresponding to MDR1a and MDR1b genes. FLS were treated with dexamethasone (DEX) and lipopolysaccharide. The mRNA and protein levels of tumor necrosis factor-alpha, interleukin (IL)-6 and IL-1beta were measured. Both siRNAs were co-transduced into rat knee joints by an electroporation method and evaluated the target gene expressions in the synovium. RESULTS: Each siRNA could sequence-specifically reduce the target gene expression by over 70% and effectively suppressed P-gp expression and function in the FLS. Both gene expression and protein production of the inflammatory cytokines in the cells transfected with siRNA were reduced by a greater amount compared to in control cells. The in vivo electroporation-mediated transduction of siRNA could significantly inhibit the target gene expressions. CONCLUSIONS: MDR1a/1b gene silencing by siRNA could effectively inhibit P-gp in rat FLS, resulting in a significant enhancement of the anti-inflammatory effects of DEX. The in vivo siRNA transduction could successfully silence MDR gene expression in the rat synovium. These findings indicate that the siRNA targeting MDR gene could be a useful tool for treating refractory arthritis in RA.
19773265 Autologous hematopoietic stem cell transplantation for autoimmune diseases: an observation 2010 Feb BACKGROUND: Autologous hematopoietic stem cell transplantation has been used since 1996 for the treatment of severe autoimmune diseases refractory to approved therapies. We evaluated the long-term outcomes of these transplants and aimed to identify potential prognostic factors. DESIGN AND METHODS: In this observational study we analyzed all first autologous hematopoietic stem cell transplants for autoimmune diseases reported to the European Group for Blood and Marrow Transplantation (EBMT) registry between 1996-2007. The primary end-points for analysis were overall survival, progression-free survival and transplant-related mortality at 100 days. RESULTS: Nine hundred patients with autoimmune diseases (64% female; median age, 35 years) who underwent a first autologous hematopoietic stem cell transplant were included. The main diseases were multiple sclerosis (n=345), systemic sclerosis (n=175), systemic lupus erythematosus (n=85), rheumatoid arthritis (n=89), juvenile arthritis (n=65), and hematologic immune cytopenia (n=37). Among all patients, the 5-year survival was 85% and the progression-free survival 43%, although the rates varied widely according to the type of autoimmune disease. By multivariate analysis, the 100-day transplant-related mortality was associated with the transplant centers' experience (P=0.003) and type of autoimmune disease (P=0.03). No significant influence of transplant technique was identified. Age less than 35 years (P=0.004), transplantation after 2000 (P=0.0015) and diagnosis (P=0.0007) were associated with progression-free survival. CONCLUSIONS: This largest cohort studied worldwide shows that autologous hematopoietic stem cell transplantation can induce sustained remissions for more than 5 years in patients with severe autoimmune diseases refractory to conventional therapy. The type of autoimmune disease, rather than transplant technique, was the most relevant determinant of outcome. Results improved with time and were associated with the transplant centers' experience. These data support ongoing and planned phase III trials to evaluate the place of autologous hematopoietic stem cell transplantation in the treatment strategy for severe autoimmune diseases.
20222110 Suppression of skin and kidney disease by inhibition of spleen tyrosine kinase in lupus-pr 2010 Jul OBJECTIVE: Spleen tyrosine kinase (Syk) is involved in membrane-mediated signaling in various cells, including immune cells. It is overexpressed in T cells from patients with systemic lupus erythematosus (SLE), and its inhibition has been shown to improve T cell function as well as to improve disease manifestations in (NZB x NZW)F(1) lupus-prone mice and in patients with rheumatoid arthritis. While clinical trials examining Syk inhibition in patients with SLE are being considered, the aim of our experiments was to determine whether the therapeutic effects of Syk inhibition extend to other strains of lupus-prone mice and whether they result in improvement in skin disease and modification of established disease. METHODS: Female MRL/lpr or BAK/BAX mice were studied. Starting either at age 4 weeks (before disease) or at age 16 weeks (after established disease) and continuing for up to 16 weeks, mice were fed chow containing the Syk inhibitor R788 or control chow. RESULTS: We found that inhibition of Syk in MRL/lpr and BAK/BAX mice prevented the development of skin disease and significantly reduced established skin disease. Similarly, Syk inhibition reduced the size of the spleen and lymph nodes, suppressed the development of renal disease, and suppressed established renal disease. Discontinuation of treatment resulted in extended suppression of skin disease for at least 8 weeks and suppression of renal disease for 4 weeks. CONCLUSION: Syk inhibition suppresses the development of lupus skin and kidney disease in lupus-prone mice, suppresses established disease in lupus-prone mice, and may represent a valuable treatment for patients with SLE.
19877030 Tumor necrosis factor alpha and interleukin-1beta modulate calcium and nitric oxide signal 2009 Nov OBJECTIVE: Inflammatory diseases often coincide with reduced bone mass. Mechanoresponsive osteocytes regulate bone mass by maintaining the balance between bone formation and resorption. Despite its biologic significance, the effect of inflammation on osteocyte mechanoresponsiveness is not understood. To fill this gap, we investigated whether the inflammatory cytokines tumor necrosis factor alpha (TNFalpha) and interleukin-1beta (IL-1beta) modulate the osteocyte response to mechanical loading. METHODS: MLO-Y4 osteocytes were incubated with TNFalpha (0.5-30 ng/ml) or IL-1beta (0.1-10 ng/ml) for 30 minutes or 24 hours, or with calcium inhibitors for 30 minutes. Cells were subjected to mechanical loading by pulsatile fluid flow (mean +/- amplitude 0.7 +/- 0.3 Pa, 5 Hz), and the response was quantified by measuring nitric oxide (NO) production using Griess reagent and by measuring intracellular calcium concentration ([Ca(2+)](i)) using Fluo-4/AM. Focal adhesions and filamentous actin (F-actin) were visualized by immunostaining, and apoptosis was quantified by measuring caspase 3/7 activity. Cell-generated tractions were quantified using traction force microscopy, and cytoskeletal stiffness was quantified using optical magnetic twisting cytometry. RESULTS: Pulsatile fluid flow increased [Ca(2+)](i) within seconds (in 13% of cells) and NO production within 5 minutes (4.7-fold). TNFalpha and IL-1beta inhibited these responses. Calcium inhibitors decreased pulsatile fluid flow-induced NO production. TNFalpha and IL-1beta affected cytoskeletal stiffness, likely because 24 hours of incubation with TNFalpha and IL-1beta decreased the amount of F-actin. Incubation with IL-1beta for 24 hours stimulated osteocyte apoptosis. CONCLUSION: Our results suggest that TNFalpha and IL-1beta inhibit mechanical loading-induced NO production by osteocytes via abrogation of pulsatile fluid flow-stimulated [Ca(2+)](i), and that IL-1beta stimulates osteocyte apoptosis. Since both NO and osteocyte apoptosis affect osteoclasts, these findings provide a mechanism by which inflammatory cytokines might contribute to bone loss and consequently affect bone mass in rheumatoid arthritis.
20302641 B-lymphocyte stimulator/a proliferation-inducing ligand heterotrimers are elevated in the 2010 INTRODUCTION: B-lymphocyte stimulator (BLyS) and a proliferation-inducing ligand (APRIL) are members of the tumor necrosis factor (TNF) family that regulate B-cell maturation, survival, and function. They are overexpressed in a variety of autoimmune diseases and reportedly exist in vivo not only as homotrimers, but also as BLyS/APRIL heterotrimers. METHODS: A proprietary N-terminal trimerization domain was used to produce recombinant BLyS/APRIL heterotrimers. Heterotrimer biologic activity was compared with that of BLyS and APRIL in a 4-hour signaling assay by using transmembrane activator and CAML interactor (TACI)-transfected Jurkat cells and in a 4-day primary human B-cell proliferation assay. A bead-based immunoassay was developed to quantify native heterotrimers in human sera from healthy donors (n = 89) and patients with systemic lupus erythematosus (SLE; n = 89) or rheumatoid arthritis (RA; n = 30). Heterotrimer levels were compared with BLyS and APRIL homotrimer levels in a subset of these samples. RESULTS: The recombinant heterotrimers consisted mostly of one BLyS and two APRIL molecules. Heterotrimer signaling did not show any significant difference compared with APRIL in the TACI-Jurkat assay. Heterotrimers were less-potent inducers of B-cell proliferation than were homotrimeric BLyS or APRIL (EC(50), nMol/L: BLyS, 0.02; APRIL, 0.17; heterotrimers, 4.06). The soluble receptor fusion proteins atacicept and B-cell maturation antigen (BCMA)-immunoglobulin (Ig) neutralized the activity of BLyS, APRIL, and heterotrimers in both cellular assays, whereas B-cell activating factor belonging to the TNF family receptor (BAFF-R)-Ig neutralized only the activity of BLyS. In human sera, significantly more patients with SLE had detectable BLyS (67% versus 18%; P < 0.0001), APRIL (38% versus 3%; P < 0.0002), and heterotrimer (27% versus 8%; P = 0.0013) levels compared with healthy donors. Significantly more patients with RA had detectable APRIL, but not BLyS or heterotrimer, levels compared with healthy donors (83% versus 3%; P < 0.0001). Heterotrimer levels weakly correlated with BLyS, but not APRIL, levels. CONCLUSIONS: Recombinant BLyS/APRIL heterotrimers have biologic activity and are inhibited by atacicept and BCMA-Ig, but not by BAFF-R-Ig. A novel immunoassay demonstrated that native BLyS/APRIL heterotrimers, as well as BLyS and APRIL homotrimers, are elevated in patients with autoimmune diseases.
19644860 Delayed acquisition of somatic hypermutations in repopulated IGD+CD27+ memory B cell recep 2009 Aug OBJECTIVE: Transient B cell depletion by rituximab has been used with clinical efficacy in the treatment of patients with rheumatoid arthritis (RA). Previous studies of B cell repopulation have shown long-term numerical reduction in memory B cells. Non-class-switched IgD+CD27+ memory B cells, in particular, repopulate slowly. This study was undertaken to determine whether mutational acquisition in individual B cell receptors in repopulating class-switched and non-class-switched memory B cells is affected by rituximab. METHODS: Cells obtained from 16 RA patients, 4 healthy donors, and 3 patients who underwent allogeneic stem cell transplantation (ASCT) were analyzed using single B cell sorting followed by nested polymerase chain reaction and Ig V(H)3 sequencing. RESULTS: There was a delayed acquisition of mutations in Ig receptors of IgD+ memory B cells over a period of 6 years after a single course of rituximab. One year after rituximab treatment, 84% of single repopulating IgD+CD27+ B cells were unmutated, and no highly mutated Ig receptors were found (compared with 52% before therapy). Over time, increasing numbers of mutations were detected. Even 6 years after rituximab treatment, however, mutations in IgD+ memory B cells were still significantly reduced. In contrast, class-switched memory B cells repopulated with quantitatively normal mutations. In comparison, in patients undergoing ASCT, IgD+ memory cells repopulated earlier with higher mutations in Ig receptors. CONCLUSION: Our data suggest that IgD+ memory B cells are particularly susceptible to the effects of rituximab, with delayed acquisition of mutations in their Ig receptors still evident 6 years after a single course of rituximab. Our findings indicate that these cells have different requirements for mutational acquisition compared with class-switched memory B cells.
20799933 High mobility group box 1 potentiates the pro-inflammatory effects of interleukin-1β in o 2010 INTRODUCTION: High mobility group box 1 (HMGB1) is released by necrotic cells or secreted in response to inflammatory stimuli. Extracellular HMGB1 may act as a pro-inflammatory cytokine in rheumatoid arthritis. We have recently reported that HMGB1 is released by osteoarthritic synoviocytes after activation with interleukin-1beta (IL-1β) The present study investigated the role of HMGB1 in synovial inflammation in osteoarthritis (OA). METHODS: HMGB1 was determined in human synovium using immunohistochemistry, comparing normal to OA. OA synoviocytes were incubated with HMGB1 at 15 or 25 ng/ml in the absence or presence of IL-1β (10 ng/ml). Gene expression was analyzed by quantitative PCR and protein expression by Western Blot and ELISA. Matrix metalloproteinase (MMP) activity was studied by fluorometric procedures and nuclear factor (NF)-κB activation by transient transfection with a NF-κB-luciferase plasmid. RESULTS: In the normal synovium, HMGB1 was found in the synovial lining cells, sublining cells, and in the vascular wall cells. The distribution of HMGB1 in OA synovium was similar but the number of HMGB1 positive cells was higher and HMGB1 was also present in infiltrated cells. In normal synovial membrane cells, HMGB1 was found mostly in the nuclei, whereas in OA, HMGB1 was generally found mostly in the cytoplasm. In OA synoviocytes, HMGB1 alone at concentrations of 15 or 25 ng/ml did not affect the production of IL-6, IL-8, CCL2, CCL20, MMP-1 or MMP-3, but in the presence of IL-1β, a significant potentiation of protein and mRNA expression, as well as MMP activity was observed. HMGB1 also enhanced the phosphorylated ERK1/2 and p38 levels, with a lower effect on phosphorylated Akt. In contrast, JNK1/2 phosphorylation was not affected. In addition, HMGB1 at 25 ng/ml significantly potentiated NF-κB activation in the presence of IL-1β. CONCLUSIONS: Our results indicate that HMGB1 is overexpressed in OA synovium and mostly present in extracellular form. In OA synoviocytes, HMGB1 cooperates with IL-1β to amplify the inflammatory response leading to the production of a number of cytokines, chemokines and MMPs. Our data support a pro-inflammatory role for this protein contributing to synovitis and articular destruction in OA.
19846760 Mapping of multiple susceptibility variants within the MHC region for 7 immune-mediated di 2009 Nov 3 The human MHC represents the strongest susceptibility locus for autoimmune diseases. However, the identification of the true predisposing gene(s) has been handicapped by the strong linkage disequilibrium across the region. Furthermore, most studies to date have been limited to the examination of a subset of the HLA and non-HLA genes with a marker density and sample size insufficient for mapping all independent association signals. We genotyped a panel of 1,472 SNPs to capture the common genomic variation across the 3.44 megabase (Mb) classic MHC region in 10,576 DNA samples derived from patients with systemic lupus erythematosus, Crohn's disease, ulcerative colitis, rheumatoid arthritis, myasthenia gravis, selective IgA deficiency, multiple sclerosis, and appropriate control samples. We identified the primary association signals for each disease and performed conditional regression to identify independent secondary signals. The data demonstrate that MHC associations with autoimmune diseases result from complex, multilocus effects that span the entire region.
21161670 A T-cell-based enzyme-linked immunospot assay for tuberculosis screening in Chinese patien 2011 Sep Anti-tumour necrosis factor-α (TNF-α) therapy brought new hopes for treating rheumatic diseases but also increased the risk of infection, including mycobacterium tuberculosis (MTb). Conventional screening tools, such as tuberculin skin test (TST), lack sensitivity or specificity. Recently, T-SPOT.TB has been introduced to detect tuberculosis infection. Reports have proved its superior performance in detecting tuberculosis infection in various patient populations than the TST. To compare the value of a T-cell-based enzyme-linked immunospot assay (ELISPOT) T-SPOT.TB and conventional (TST) in screening and monitoring tuberculosis in patients with rheumatic diseases during infliximab therapy in China. Fifty-eight patients with various rheumatic diseases who received infliximab therapy were enrolled in the trial. Freshly isolated peripheral blood mononuclear cells were stimulated with MTb-specific antigens (ESAT-6 and CFP10), and IFN-γ-producing cells were counted. TST was performed with 1 TU PPD injected intradermally into the volar aspect of forearm. A cutaneous induration with diameter ≥5 mm was considered as positive TST, and an increment ≥5 mm of cutaneous induration was considered as TST conversion. TST and T-SPOT.TB test were carried out at baseline and repeated 12 months after infliximab therapy (if no active TB occurs) or at times when TB occurred. Moreover, all patients were initially evaluated for latent tuberculosis infection (LTBI) with clinical examination and chest radiograph. The McNemar test was used for TST and T-SPOT.TB concordance analysis. Cohen's kappa coefficient was used to assess strength of the agreement. Among the 58 patients evaluated, 25 (43.1%) had ankylosing spondylitis, 24 (41.4%) had rheumatoid arthritis, 4 (6.9%) had undifferentiated spondyloarthropathy, 3 (5.2%) had psoriatic arthritis and 2 (3.4%) had reactive arthritis. A total of 52 patients (89.7%) had previously received vaccination with Bacille Calmette-Guerin. All of the patients received either single or combination of disease modifying anti-rheumatic drug (DMARDs) therapy, and 16 (27.4%) had previously or presently received glucocorticoid therapy. Before infliximab therapy, 12 patients (20.7%) had positive and 46 (79.3%) had negative TST results, and only 1 (1.7%) had positive T-SPOT.TB. Among 51 patients completing the repeated TST and T-SPOT.TB assay, 7 patients (13.7%) had TST conversion and 4 (7.8%) had positive T-SPOT.TB results. Of 7 patients with TST conversion, 2 patients (28.6%) developed active TB and also had positive T-SPOT.TB results; of 44 patients with no TST conversion, 2 patients (4.5%) had positive T-SPOT.TB and 1 (2.3%) had active TB. If 5 mm was used as the cut-off value of TST, TST and T-SPOT.TB, had an agreement value of 68.6% with a kappa value of 0.166. If 10 mm was used as the cut-off value, the agreement between TST and T-SPOT.TB was 88.2% with a kappa value of 0.338. T-SPOT.TB was more specific than TST in detecting tuberculosis during infliximab therapy in China with high BCG vaccination and high prevalence of TB. It can be used as a reliable tool for TB monitoring during infliximab therapy in Chinese patients with rheumatic diseases. Finally, it is recommended to repeat the TST and T-SPOT.TB periodically during biological treatment.
21085612 HIV-1 induces DCIR expression in CD4+ T cells. 2010 Nov 11 The C-type lectin receptor DCIR, which has been shown very recently to act as an attachment factor for HIV-1 in dendritic cells, is expressed predominantly on antigen-presenting cells. However, this concept was recently challenged by the discovery that DCIR can also be detected in CD4(+) T cells found in the synovial tissue from rheumatoid arthritis (RA) patients. Given that RA and HIV-1 infections share common features such as a chronic inflammatory condition and polyclonal immune hyperactivation status, we hypothesized that HIV-1 could promote DCIR expression in CD4(+) T cells. We report here that HIV-1 drives DCIR expression in human primary CD4(+) T cells isolated from patients (from both aviremic/treated and viremic/treatment naive persons) and cells acutely infected in vitro (seen in both virus-infected and uninfected cells). Soluble factors produced by virus-infected cells are responsible for the noticed DCIR up-regulation on uninfected cells. Infection studies with Vpr- or Nef-deleted viruses revealed that these two viral genes are not contributing to the mechanism of DCIR induction that is seen following acute infection of CD4(+) T cells with HIV-1. Moreover, we report that DCIR is linked to caspase-dependent (induced by a mitochondria-mediated generation of free radicals) and -independent intrinsic apoptotic pathways (involving the death effector AIF). Finally, we demonstrate that the higher surface expression of DCIR in CD4(+) T cells is accompanied by an enhancement of virus attachment/entry, replication and transfer. This study shows for the first time that HIV-1 induces DCIR membrane expression in CD4(+) T cells, a process that might promote virus dissemination throughout the infected organism.
20938960 Increased amphiregulin expression as a biomarker of cholesteatoma activity. 2010 Nov OBJECTIVES/HYPOTHESIS: The purpose of this study was to evaluate human surgical specimens for cholesteatoma-associated changes in amphiregulin expression and determine potential relations to clinical disease variables. Amphiregulin, an epidermal growth factor receptor ligand, has functions in normal epithelial proliferation and aberrant neoplastic cell growth and is proinflammatory (e.g., rheumatoid arthritis, fibrosis) and active in hyperproliferative cutaneous conditions including psoriasis and wound healing. These known amphiregulin activities and the characteristic epithelial expansion and bone erosion of cholesteatoma pathophysiology prompted testing of the hypothesis that amphiregulin expression levels are altered in cholesteatoma and correlate to the disease state. STUDY DESIGN: Prospective experimental study, cross-sectional analysis. METHODS: Relative changes in amphiregulin gene expression were quantitated by real-time reverse-transcription polymerase chain reaction analyses of cholesteatoma epithelium compared to uninvolved control tissues from patients' postauricular and external auditory canal regions. Western immunoblot assays were performed for qualitative evaluation of amphiregulin protein expression. The t test and Fisher exact test were used for analysis. RESULTS: A statistically significant increase in amphiregulin gene expression was associated with cholesteatoma specimens compared to uninvolved postauricular skin (PAS) and external auditory canal (EAC) skin, P = .004 and P = .002, respectively. From comparisons of 60 sets of skin pairs, the mean ratio of amphiregulin RNA expression for cholesteatoma/PAS is 4.94 (standard error of the mean [SEM] = 1.53, n = 30) and for cholesteatoma/EAC is 7.70 (SEM = 1.57, n = 30). CONCLUSIONS: Amphiregulin is overexpressed in epithelial tissues of human cholesteatoma. Significant relationships were identified between increased amphiregulin expression levels and the extent of cholesteatoma migration and bone erosion. Our study results indicate amphiregulin is a potential biomarker of early cholesteatoma disease processes.
20696559 Modulation of the immune system by Boswellia serrata extracts and boswellic acids. 2010 Sep Extracts from the gum resin of Boswellia serrata and some of is constituents including boswellic acids affect the immune system in different ways. Among the various boswellic acids 11-keto-beta-boswellic acid (KBA) and acetyl-11-keto-beta-boswellic acid have been observed to be active. However, also other boswellic acids may exhibit actions in the immune system. In the humoral defence system a mixture of boswellic acis at higher doses reduced primary antibody titres; on the other hand lower doses enhanced secondary antibody titres following treatment with sheep erythrocytes. In the cellular defence boswellic acides appear to increase lymphocyte proliferation whereas higher concentrations are even inhibitory. Moreover, BAs increase phagocytosis of macrophages. BAs affect the cellular defence system by interaction with production/release of cytokines. Thus, BAs inhibit activation of NFkappaB which is a product of neutrophile granulocytes. Consequently a down regulation of TNF-alpha and decrease of IL-1, IL-2, IL-4, IL-6 and IFN-gamma, which are proinflammatory cytokines by BEs and BAs has been reported. Suppressions of the classic way of the complement system was found to be due to inhibition of the conversion of C3 into C3a and C3b. However, which of these pharmacological actions contribute to the therapeutic effects and which is finally the best dosage of a standardized extract needs further examination. And it is also a question whether or not a single BA will have the same therapeutic effect as a standardized extract. Among the mediators of inflammatory reaction, mast cell stabilisation has been described by a BE. Inhibition of prostaglandin synthesis appears to play only a minor role as far as the anti-inflammatory effect is concerned. On the other hand the inhibitory action of BAs on 5-LO leading to a decreased production of leukotrienes has received high attention by the scientific community since a variety of chronic inflammatory diseases is associatied with increased leukotriene activity. At the end of the cascade of events in the cellular immune system as far as it directs to various tissues of the body - i.e. autoimmune diseases - formation of oxygen radicals and proteases (for example elastase) play an important destructive role. Here, BEs as well as BAs have been found to be inhibitory. From the pharmacological properties of BEs and BAs it is not surprising that positive effects of BEs in some chronic inflammatory diseases including rheumatoid arthritis, bronchial asthma, osteoarthritis, ulcerative colitis and Crohn's disease have been reported.
20635054 Organising pneumonia - the experience of an outpatient clinic of a central hospital. 2010 May AIM: to characterise outpatients of a Portuguese central hospital diagnosed with organising pneumonia (OP) and compare results with current literature. METHODS: medical processes with diagnosis of OP were retrospectively studied as to demographics, aetiology, clinical and radiological features, average time until and date of diagnosis, laboratory and histological changes, treatment and relapse. Results - thirteen patients with a mean follow -up of 171.6 weeks (max 334 and min 28 weeks) were evaluated. Nine of these patients (70%) had cryptogenic OP (COP) while 30% had secondary OP (SOP), two with rheumatoid arthritis, one with dermatomyositis and another undergoing radiotherapy for breast cancer. Mean age was 55.6 (+ -15.3 years), 92% female, 77% were non -smokers. Average time until diagnosis was 77.2 weeks (min 3 and max 432 weeks). Symptoms at presentation were tiredness (92%), cough (85%), fever (65%), shortness of breath (54%), thoracic pain (23%) and weight loss (23%). At the time of diagnosis, the mean erythrocyte sedimentation rate was 70mm (max 170mm and min 16mm). C -reactive protein level was increased in eight patients. Significant leucocytosis was absent. Chest X -ray and chest CT scan showed bilateral distribution in 12 patients (92%). Consolidation with an air bronchogram was present in 12 patients and in four (31%), consolidation was migratory. Four patients (30%) underwent transbronchial pulmonary biopsy, all uncharacteristic and eight patients surgical pulmonary biopsy, four showed histological confirmation of SOP. Corticosteroids were started in 11 patients and average treatment was 61.6 weeks (16-288 weeks). 15% (2/13) had spontaneous resolution. Four patients (31%) relapsed, one of them five times. Two patients are dependent on a low dose of corticosteroids, one due to underlying disease and another due to multiple relapses. Therapy of relapse was corticosteroids alone in minimum effective dosage or associated to azathioprine or ciclosporin. DISCUSSION AND CONCLUSION: such a high incidence in females (92%) may be explained by the limited sample of patients. In 70% of the patients diagnosis were established by clinical and radiology criteria. Mean time to diagnosis was very variable which suggests that in some cases the disease was not diagnosed and treated as another interstitial lung disease or as recurrent pneumonia. Most patients (53.8%) had a favourable clinical course after treatment with corticosteroids with a very low number of relapses (30.8%), much lower than described by other authors (60%). Only in experienced centres should the diagnosis of OP established by clinical and radiological criteria.
20429914 ParallABEL: an R library for generalized parallelization of genome-wide association studie 2010 Apr 29 BACKGROUND: Genome-Wide Association (GWA) analysis is a powerful method for identifying loci associated with complex traits and drug response. Parts of GWA analyses, especially those involving thousands of individuals and consuming hours to months, will benefit from parallel computation. It is arduous acquiring the necessary programming skills to correctly partition and distribute data, control and monitor tasks on clustered computers, and merge output files. RESULTS: Most components of GWA analysis can be divided into four groups based on the types of input data and statistical outputs. The first group contains statistics computed for a particular Single Nucleotide Polymorphism (SNP), or trait, such as SNP characterization statistics or association test statistics. The input data of this group includes the SNPs/traits. The second group concerns statistics characterizing an individual in a study, for example, the summary statistics of genotype quality for each sample. The input data of this group includes individuals. The third group consists of pair-wise statistics derived from analyses between each pair of individuals in the study, for example genome-wide identity-by-state or genomic kinship analyses. The input data of this group includes pairs of SNPs/traits. The final group concerns pair-wise statistics derived for pairs of SNPs, such as the linkage disequilibrium characterisation. The input data of this group includes pairs of individuals. We developed the ParallABEL library, which utilizes the Rmpi library, to parallelize these four types of computations. ParallABEL library is not only aimed at GenABEL, but may also be employed to parallelize various GWA packages in R. The data set from the North American Rheumatoid Arthritis Consortium (NARAC) includes 2,062 individuals with 545,080, SNPs' genotyping, was used to measure ParallABEL performance. Almost perfect speed-up was achieved for many types of analyses. For example, the computing time for the identity-by-state matrix was linearly reduced from approximately eight hours to one hour when ParallABEL employed eight processors. CONCLUSIONS: Executing genome-wide association analysis using the ParallABEL library on a computer cluster is an effective way to boost performance, and simplify the parallelization of GWA studies. ParallABEL is a user-friendly parallelization of GenABEL.
20042802 Arterial and venous thromboembolic events during anti-TNF therapy: a study of 85 spontaneo 2009 BACKGROUND: Systemic inflammation such as rheumatoid arthritis (RA) and Crohn's disease (CD) may be responsible for vascular comorbidity. TNF-alpha blockade was expected to lower these comorbidities but several cases of arterial and venous thromboembolic events (TE) have been reported. OBJECTIVES: The aim of this work was to study retrospectively the main characteristics of spontaneously notified TNF-alpha blockers related TE over a 7-year period. METHODS: TE related to infliximab, etanercept and adalimumab spontaneously notified to the French adverse drug reporting system database between January 2000 and December 2006 were analyzed. Separate analysis of arterial TE and venous TE was performed. Risk factors for each category of TE were assessed with consensual criteria. RESULTS: 85 TE were analyzed, representing 4.5% of all the spontaneously notified adverse reactions of the 3 TNF-alpha blockers in the database. 42 were arterial events and 43 were venous events. The incidence was not significantly different between the 3 TNF-alpha blockers. Mean delay of TE onset after treatment initiation was 10.6 months. It was significantly shorter for etanercept (6.1 months, p=0.001) especially for venous TE (2.4 months). 16 among the 42 patients with arterial TE had 2 or more risk factors whereas 39 among the 43 patients with venous TE had no RF or only one. Most of patients (79/85) received concomitant systemic corticosteroids and/or methotrexate and/or COX-2 selective inhibitors. 23 patients had been investigated for autoimmunity, 13 had antinuclear and/or antiphospholipid antibodies. Main limitations of this study were underreporting and heterogeneous report contents. CONCLUSION: Despite its limitations, this study suggests that venous TE could be favoured by TNF-alpha blockers therapy since they occurred in patients with no or few risk factors for venous thrombosis. However, this needs to be more evaluated by controlled studies.
20039311 Osteoclast-specific Dicer gene deficiency suppresses osteoclastic bone resorption. 2010 Apr 1 Osteoclasts are unique cells that resorb bone, and are involved in not only bone remodeling but also pathological bone loss such as osteoporosis and rheumatoid arthritis. The regulation of osteoclasts is based on a number of molecules but full details of these molecules have not yet been understood. MicroRNAs are produced by Dicer cleavage an emerging regulatory system for cell and tissue function. Here, we examine the effects of Dicer deficiency in osteoclasts on osteoclastic activity and bone mass in vivo. We specifically knocked out Dicer in osteoclasts by crossing Dicer flox mice with cathepsin K-Cre knock-in mice. Dicer deficiency in osteoclasts decreased the number of osteoclasts (N.Oc/BS) and osteoclast surface (Oc.S/BS) in vivo. Intrinsically, Dicer deficiency in osteoclasts suppressed the levels of TRAP positive multinucleated cell development in culture and also reduced NFATc1 and TRAP gene expression. MicroRNA analysis indicated that expression of miR-155 was suppressed by RANKL treatment in Dicer deficient cells. Dicer deficiency in osteoclasts suppressed osteoblastic activity in vivo including mineral apposition rate (MAR) and bone formation rate (BFR) and also suppressed expression of genes encoding type I collagen, osteocalcin, Runx2, and Efnb2 in vivo. Dicer deficiency in osteoclasts increased the levels of bone mass indicating that the Dicer deficiency-induced osteoclastic suppression was dominant over Dicer deficiency-induced osteoblastic suppression. On the other hand, conditional Dicer deletion in osteoblasts by using 2.3 kb type I collagen-Cre did not affect bone mass. These results indicate that Dicer in osteoclasts controls activity of bone resorption in vivo.
20028802 Illness deception and work: incidence, manifestations and detection. 2010 Mar BACKGROUND: Illness deception (ID) may be difficult to detect. Objective techniques that improve a doctor's skills of detection will have benefits for the health economy. AIMS: To ascertain the incidence of ID in a general occupational medicine clinic, to give examples by way of case vignettes how it may manifest and to compare the variability of maximal grip strength measurements of patients with suspected simulated weakness of grip with controls. METHODS: Four hundred consecutive new patient referrals were examined by the author and those who met Diagnostic and Statistical Manual-IV criteria for factitious disorder (FD) or malingering identified. Those with suspected simulated weakness of grip were asked to perform three consecutive maximal grips with a Jamar hand dynamometer. One hundred normal subjects and 100 patients with rheumatoid arthritis (RA) of the hands were similarly tested. RESULTS: Thirty-two of 400 (8%) patients exhibited behaviour in keeping with ID (29 malingering and 3 FD). Cases included simulated hand-arm vibration syndrome, occupational asthma, deafness and weakness of a limb. The median and 90th percentile for coefficient of variation (CV) of three consecutive maximal grip strengths for normal subjects and patients with RA were 5.2, 10.5%; 5.4, 14.5% right and 4.5, 10.2%; 6.0, 14.4% left hand, respectively. The CV of the six patients who simulated weakness of grip was from 17.3 to 37.8%. CONCLUSIONS: ID is relatively common in occupational medical practice and multiform in its manifestations. Simulated weakness of grip should be suspected when consecutive declared maximal grip strengths are inexplicably submaximal for age and sex and highly variable in force.
20025587 Myocardial inflammation in autoimmune diseases: investigation by cardiovascular magnetic r 2009 Dec INTRODUCTION: Myocardial inflammation often coexists with different types of autoimmune diseases. Our aim was to investigate the presence of myocarditis in these patients by Cardiovascular Magnetic Resonance (CMR) and endomyocardial biopsy. PATIENTS-METHODS: Twenty patients, aged 20-55 yrs with autoimmune diseases and cardiac symptoms (3 with Takayasu's arteritis, 3 with systemic lupus erythematosus, 5 with rheumatoid arthritis, 7 with autoimmune thyroid disease and 2 with systemic sclerosis) and 20 patients with the same autoimmune diseases but without cardiac symptoms (controls) were studied. The presence of myocarditis and LV function were evaluated by CMR. Myocarditis was documented using T2-weighted (T2-W), T1-weighted (T1-W) before and after contrast media injection and late enhanced images. In 10 patients (positive for myocarditis by CMR with either low LVEF or recent increase in troponin), endomyocardial biopsy was also performed. Myocardial specimens were evaluated by histology and polymerase chain reaction techniques (PCR). RESULTS: Myocarditis was identified in 18/20 patients by CMR. In the T2-W images the signal ratio of myocardium to skeletal muscle was 1.89+/-0.25 (control values 1.57+/-0.13, p<0.05). From the T1-W images the relative myocardial enhancement was 11.31+/-11.18 (control values 3.09+/-0.05, p<0.05). Epicardial late gadolinium enhanced areas were identified in 18/20. In myocardial specimens, histology revealed inflammation in 5/10 (50%) and PCR documented viral or microbial genomes in 8/10 (80%). Positive histology and PCR were in agreement with 50% and 80% of positive CMR examinations, respectively. Herpes virus was identified in 3/10, Adeno in 1/10, Coxsackie B6 in 1/10, echo in 1/10, Parvo-B19 in 3/10, CMV in 1/10 and Chlamydia trachomatis in 8/10. CONCLUSIONS: Myocardial inflammation is a common finding in patients with autoimmune diseases and cardiac symptoms. The diagnosis can be confirmed by CMR, which is a noninvasive and reliable tool for the investigation of these patients.