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ID PMID Title PublicationDate abstract
16802369 Salivary gland epithelial cells: a new source of the immunoregulatory hormone adiponectin. 2006 Jul OBJECTIVE: Adiponectin is an adipocytokine that displays insulin-sensitizing and immunoregulatory properties. Adipocyte development in association with fibrosis is frequently detected in primary Sjögren's syndrome lesions, connoting a healing process. The aim of this study was to examine the expression of adiponectin in minor salivary gland biopsy specimens obtained from patients with primary SS and controls. METHODS: The expression of adiponectin in minor salivary gland biopsy specimens and in long-term-cultured non-neoplastic salivary gland epithelial cell (SGEC) lines obtained from patients with primary SS and control subjects was examined, using immunohistochemistry and immunoblotting, respectively. The expression of adiponectin, adiponectin receptor 1 (AdipoR1), and AdipoR2 messenger RNA (mRNA) by SGECs was investigated by reverse transcription-polymerase chain reaction. RESULTS: Immunohistochemical analysis for adiponectin revealed positive staining of adipocytes from primary SS lesions as well as ductal epithelial cells from both patients with primary SS and controls. All of the SGEC lines tested were shown to express adiponectin, AdipoR1, and AdipoR2 mRNA, whereas adiponectin protein expression was detected by immunoblotting in SGECs from patients with primary SS but not in those from controls. The analysis of concentrated culture supernatants also revealed increased adiponectin expression by SGECs from patients with SS compared with controls. CONCLUSION: Our findings provide novel evidence that adiponectin is produced by SGECs. The high constitutive expression of adiponectin by SGECs from patients with primary SS is likely attributable to aberrant activation of these cells. Although the significance of adiponectin expression remains unknown, it is possible that adiponectin functions in an autocrine manner, as suggested by concurrent expression of the relevant receptors.
15590764 Hydroxychloroquine therapy in patients with primary Sjögren's syndrome may improve saliva 2005 Apr OBJECTIVE: To determine whether (i) cholinesterase activity is increased in the saliva of patients with primary Sjogren's syndrome (pSS), (ii) increased levels of cholinesterase of lymphocyte origin could interfere with the secretory activity of submandibular acinar cells, and (iii) hydroxychloroquine at therapeutic doses could interfere with cholinesterase activity. METHODS: The Ellman method was used to determine the levels of salivary cholinesterase activity and the K(i) of both chloroquine and hydroxychloroquine for serum cholinesterase. The ability of lymphocyte cholinesterase to inhibit the acetylcholine (ACh)-evoked rise in [Ca(2+)](i) in mouse submandibular acinar cells was determined using fura-2 microfluorimetry. RESULTS: Patients with pSS had significantly higher levels of cholinesterase activity in both their unstimulated (P < 0.05) and stimulated saliva (P < 0.0001) compared with control subjects. Lymphocyte cholinesterase was capable of inhibiting the ACh-evoked rise in [Ca(2+)](i). The in vitro K(i) for hydroxychloroquine inhibition of cholinesterase was 0.38 +/- 1.4 microM. CONCLUSION: These data suggest that increased levels of cholinesterase present in the salivary glands of patients with pSS may contribute to glandular hypofunction and provide evidence that the therapeutic enhancement of salivary secretion in patients with pSS by hydroxychloroquine may be mediated by inhibition of glandular cholinesterase activity, although further in vivo investigation is needed.
16949042 Patients with inflammatory arthritic diseases harbor elevated serum and synovial fluid lev 2006 Oct 20 In K/BxN mice, anti-glucose-6-phosphate isomerase (G6PI) IgG antibodies (Abs) cause joint-specific inflammation and destruction. Anti-G6PI Abs are also present in humans with inflammatory arthritis, especially among patients with rheumatoid arthritis (RA). A contributing factor to the induction of such autoantibodies may be upregulated expression of the corresponding antigen G6PI in affected tissues and/or increased levels of G6PI in the circulation. To determine G6PI levels and the presence of free G6PI and/or G6PI-containing immune complexes in sera and synovial fluids (SF) of patients with different arthritides, serum and SF obtained concomitantly from 91 clinically well-defined arthritis patients were assessed in a blinded manner for G6PI enzymatic assay and for G6PI protein concentration by ELISA. Sera and SF from patients with immune-based inflammatory arthritis contained significantly higher levels of G6PI enzymatic activity compared to sera or SF from patients with non-immune-based inflammatory arthritis or healthy controls. In addition, significantly higher levels of total G6PI protein concentration (including both enzymatically active and inactive forms) were present in sera of RA patients vs. those with other immune-based or non-immune-based inflammatory arthritis.G6PI in sera and SF were present both as G6PI-containing immune complexes and as free G6PI, with the majority of free G6PI existing as tetramers with lesser amounts of dimers and monomers. Levels of G6PI enzymatic activity in the sera of most immune-based inflammatory arthritis patients are elevated and may reflect ongoing inflammation and cell destruction. The high serum levels of enzymatically inactive forms of G6PI in RA relative to those in other arthritic diseases are partially due to G6PI-containing immune complexes, a portion of which also contains C1q. Overall, our study supports the notion that elevated G6PI levels present in patients with immune-based inflammatory arthritis may contribute to elevated levels of anti-G6PI Abs and G6PI/anti-G6PI immune complexes. This, in turn, may trigger production of proinflammatory cytokines and perpetuate the inflammatory process.
16166849 FDG PET-CT demonstration of Sjogren's sialoadenitis. 2005 Oct We report the positron emission tomography-computed axial tomography (PET-CT) appearance of the inflammatory involvement of the salivary glands of a 69-year-old female with a history of lymphoma and known primary Sjogren's syndrome. Hybrid PET-CT was performed 5 months after completion of chemotherapy using a Siemens Biograph scanner (Knoxville, TN) 45 minutes after intravenous administration of 15 mCi of F-18 fluorodeoxyglucose (FDG). CT transmission scan was obtained for attenuation correction. PET-CT demonstrated no evidence of hypermetabolic nodal disease but showed symmetric intensely hypermetabolic submandibular and parotid salivary glands.
15967078 Recent advances in the management of ocular complications of Sjögren's syndrome. 2005 Jul Sjögren's syndrome (SS) is an autoimmune disorder, the principal ocular manifestation of which is decreased tear production leading to chronic irritation and damage to the corneal and conjunctival epithelium. The most important advance in the treatment of ocular manifestations of SS is the introduction of topical anti-inflammatory agents such as cyclosporine A, which increases tear production and decreases symptoms without any significant side effect. Stimulators of tear secretion, both topical, such as diquafosol, and systemic, such as pilocarpine and cevimeline, are also effective, although they have been associated with frequent side effects. Topical use of autologous serum is another new and effective form of treatment, but problems in the preparations prevent their widespread use. Additionally, nonpharmacologic treatments, such as insertion of punctal plugs, are beneficial in the dry eye of SS, whereas several other modalities, such as anti-CD4 monoclonal antibody eye drops and gene transfer, are still in experimental phases.
17040883 [Acute polyarthritis during a parvovirus B19 primary infection]. 2006 Sep Parvovirus B19 classically causes erythema infectiosum in children, febrile arthralgia or acute erythroblastopenia in adult. The clinical spectrum of adult primary infection is sometimes misleading. We report an observation of an acute rheumatoid-like arthritis following primary parvovirus B19 infection in a 42-year-old woman.
16563174 A promoter haplotype of the interleukin-18 gene is associated with juvenile idiopathic art 2006 Recently, we reported that genetic polymorphisms within the human IL18 gene were associated with disease susceptibility to adult-onset Still's disease (AOSD), which is characterized by extraordinarily high serum levels of IL-18. Because high serum IL-18 induction has also been observed in the systemic type of juvenile idiopathic arthritis (JIA), we investigated whether similar genetic skewing is present in this disease. Three haplotypes, S01, S02, and S03, composed of 13 genetic polymorphisms covering two distinct promoter regions, were determined for 33 JIA patients, including 17 with systemic JIA, 10 with polyarthritis, and 6 with oligoarthritis. Haplotypes were also analyzed for 28 AOSD patients, 164 rheumatoid arthritis (RA) patients, 102 patients with collagen diseases, and 173 healthy control subjects. The frequency of individuals carrying a diplotype configuration (a combination of two haplotypes) of S01/S01 was significantly higher in the JIA patients, including all subgroups, than in the healthy controls (P = 0.0045, Fischer exact probability test; odds ratio (OR) = 3.55, 95% confidence interval (CI) = 1.55-8.14). In patients with systemic JIA, its frequency did not differ statistically from that of normal controls. Nevertheless, it is possible that haplotype S01 is associated with the phenotype of high IL-18 production in systemic JIA because the patients carrying S01/S01 showed significantly higher serum IL-18 levels compared with patients with other diplotype configurations (P = 0.017, Mann-Whitney U test). We confirmed that the frequency of the diplotype configuration of S01/S01 was significantly higher in AOSD patients than in healthy control subjects (P = 0.011, OR = 3.45, 95% CI = 1.42-8.36). Furthermore, the RA patients were also more predisposed to have S01/S01 (P = 0.018, OR = 2.00, 95% CI = 1.14-3.50) than the healthy control subjects, whereas the patients with collagen diseases did not. In summary, the diplotype configuration of S01/S01 was associated with susceptibility to JIA as well as AOSD and RA, and linked to significantly higher IL-18 production in systemic JIA. Possession of the diplotype configuration of S01/S01 would be one of the genetic risk factors for susceptibility to arthritis in the Japanese population.
16951943 Tumour necrosis factor alpha promoter polymorphisms and etanercept therapy in juvenile idi 2007 Feb The objective of this study was to investigate the influence of TNF-alpha promoter alleles on clinical response to etanercept therapy in JIA. TNF-alpha promoter polymorphisms at positions -163, -238, -244, -308, -376 were determined in 137 JIA patients treated with etanercept for at least 3 months. A PCR fragment of about 500 bp of the TNF gene promoter was amplified. Polymorphisms were detected by a single sequencing procedure. Patients with the genotype -308GG achieved an ACR-JRA 30 response at month 6 more frequently than patients with the genotype -308GA or AA. This was already notable at month 3 of therapy. This difference in the total patient group is attributable to the JIA subgroup with rheumatoid factor negative polyarthritis. In this subgroup, patients with the -308GG genotype achieved an ACR-JRA 30 response more frequently than those with the -308GA or AA genotype (84 vs. 33% at months three, P < 0.01, 93 vs. 67% at months six, P < 0.05). There was no influence of the -238 TNF-alpha promoter alleles on clinical response. The rare alleles at position -376 or at positions -163 and -244 were too infrequent. There is an association between TNF gene promoter polymorphisms and response to etanercept in rheumatoid factor negative polyarticular JIA.
15627075 Diagnosis and treatment of psoriatic arthritis. 2005 Jan Psoriatic arthritis is a chronic, heterogeneous disease whose pathogenesis is unknown, although genetic, environmental, and immunologic factors play major roles. Psoriatic arthritis can follow an aggressive clinical course, and differentiating it from other arthropathies is sometimes difficult. Diagnosis of psoriatic arthritis is based on history, physical examination, the usual absence of rheumatoid factor, and characteristic radiographic features. At least 40% of patients with psoriatic arthritis develop radiographically detectable joint destruction; therefore, proper diagnosis and early treatment can have a significant impact on disease course and outcome. Understanding the pathogenesis of psoriatic disease has led to the use of several biologic agents that work by modulating T-cell signaling or by inhibiting key cytokines involved in inflammation, such as tumor necrosis factor (TNF). TNF inhibitors have demonstrated excellent efficacy in resolving skin and joint disease in patients with psoriatic arthritis and have been shown to be safe agents in various inflammatory disorders. This article reviews the diagnostic and treatment challenges of psoriatic arthritis as they relate to pathogenesis and burden of disease. LEARNING OBJECTIVE: At the conclusion of this learning activity, participants should have acquired a more comprehensive knowledge of our current understanding of the classification, clinical presentation, etiology, pathophysiology, differential diagnosis, and treatment of psoriatic arthritis.
16095110 Inhibition of glycinamide ribonucleotide formyltransferase results in selective inhibition 2005 Jul OBJECTIVE: To determine the effects of a glycinamide ribonucleotide formyltransferase (GARFT) inhibitor on macrophage inflammatory processes and in vivo in rat adjuvant arthritis. METHODS: GARFT inhibitors, LY309886 (6S-2',5'-thienyl-5, 10-dideazatetrahydrofolic acid) and LY329201 (R)-N-[[5-[2-(2-amino-1,4,5,6,7,8-hexahydro-4-oxopyrido[2,3-d]pyrimidin-6-yl)ethyl]-2-thienyl]carbonyl]-L-glutamatic acid disodium salt, were investigated in vitro and ex vivo on primary murine peritoneal macrophages and in the RAW macrophage cell line for both purine depletion and inhibition of LPS induced monokine secretion. In vivo efficacy following GARFT inhibition was evaluated in modified rat adjuvant arthritis. RESULTS: LY309886 inhibited purine biosynthesis in the RAW cell line with an EC50 of 90 nM, an effect readily reversible with exogenous hypoxanthine. LY309886 and LY329201 also inhibited LPS induced TNF alpha and MIP1 alpha in these cells and in primary macrophages. A similar effect could be demonstrated ex vivo with mice dosed for two days with 3 mg/kg of LY329201. LY329201 as well as methotrexate demonstrated a dose dependent reduction in both paw and spleen weight and improved joint histology following 2 weeks of dosing in a rat adjuvant arthritis study. CONCLUSION: These results suggest that GARFT inhibitors should be tested in the treatment of rheumatoid arthritis by considering their mechanism of action, here successfully tested on activated macrophages.
15899053 Intra-articular injections of high-molecular-weight hyaluronic acid have biphasic effects 2005 To assess the potential use of hyaluronic acid (HA) as adjuvant therapy in rheumatoid arthritis, the anti-inflammatory and chondroprotective effects of HA were analysed in experimental rat antigen-induced arthritis (AIA). Lewis rats with AIA were subjected to short-term (days 1 and 8, n = 10) or long-term (days 1, 8, 15 and 22, n = 10) intra-articular treatment with microbially manufactured, high-molecular-weight HA (molecular weight, 1.7 x 10(6) Da; 0.5 mg/dose). In both tests, 10 buffer-treated AIA rats served as arthritic controls and six healthy animals served as normal controls. Arthritis was monitored by weekly assessment of joint swelling and histological evaluation in the short-term test (day 8) and in the long-term test (day 29). Safranin O staining was employed to detect proteoglycan loss from the epiphyseal growth plate and the articular cartilage of the arthritic knee joint. Serum levels of IL-6, tumour necrosis factor alpha and glycosaminoglycans were measured by ELISA/kit systems (days 8 and 29). HA treatment did not significantly influence AIA in the short-term test (days 1 and 8) but did suppress early chronic AIA (day 15, P < 0.05); however, HA treatment tended to aggravate chronic AIA in the long-term test (day 29). HA completely prevented proteoglycan loss from the epiphyseal growth plate and articular cartilage on day 8, but induced proteoglycan loss from the epiphyseal growth plate on day 29. Similarly, HA inhibited the histological signs of acute inflammation and cartilage damage in the short-term test, but augmented acute and chronic inflammation as well as cartilage damage in the long-term test. Serum levels of IL-6, tumour necrosis factor alpha, and glycosaminoglycans were not influenced by HA. Local therapeutic effects of HA in AIA are clearly biphasic, with inhibition of inflammation and cartilage damage in the early chronic phase but with promotion of joint swelling, inflammation and cartilage damage in the late chronic phase.
16257179 Naive transgenic T cells expressing cartilage proteoglycan-specific TCR induce arthritis u 2005 Nov Proteoglycan (PG)-induced arthritis (PGIA), a murine model for rheumatoid arthritis (RA), is driven by antigen (PG)-specific T and B cell activation. In order to analyze the pathogenic role of antigen-specific T cells in the development of autoimmune arthritis, we have generated a transgenic (Tg) mouse. The CD4(+) T cells of this TCR-5/4E8-Tg line express a functional T cell receptor (TCR) composed of the Valpha1.1 and Vbeta4 chains with specificity for the dominant arthritogenic T cell epitope of human cartilage PG. Adoptive transfer of naive TCR-5/4E8-Tg cells induced arthritis with severe clinical symptoms in syngeneic immunodeficient BALB/c.RAG2(-/-) mice. In vivo activation of TCR-5/4E8-Tg CD4(+)Vbeta4(+) cells with cartilage PG seemed to be critical for arthritis induction. Arthritis never developed after transfer of naive wild-type cells. The arthritis was characterized as a chronic progressive disease with intermittent spontaneous exacerbations and remissions. Inflamed joints showed extensive cartilage damage and bone erosions leading to massive ankylosis in peripheral joints. These PG epitope-specific TCR-5/4E8-Tg mice can be valuable research tools for studying antigen-driven T cell regulation in arthritis, and migration of T cells to the joints. In addition the model may be used for the development of immune modulating strategies in T cell-mediated autoimmune diseases.
16574227 Somatic mutations and activation-induced cytidine deaminase (AID) expression in establishe 2007 Jan Epstein-Barr virus (EBV) transforms human peripheral B cells into lymphoblastoid cell lines (LCLs), allowing the production of specific antibody-secreting cell lines. We and others have previously found that in contrast to peripheral blood B cells, EBV-transformed lymphoblastoid cell lines express the activation-induced cytidine deaminase (AID) gene. The opposite is true for the germinal center-specific BCL6 gene: it is expressed in adult peripheral blood B cells and is no longer expressed in LCLs. The present work extends our findings and shows that whereas AID expression is rapidly induced following EBV infection, BCL6 expression is gradually down-regulated and is fully extinguished in already established LCLs. The question of whether AID activation induces the process of somatic hypermutation (SHM) was investigated in adult-derived LCLs. It was found that the VH gene from the rheumatoid factor-producing RF LCL (derived from a rheumatoid arthritis patient), accumulated somatic point mutations in culture. Overall, nine unique mutations have accumulated in the rearranged VH gene since the generation of the RF cell line. Four additional intraclonal mutations were found among 10 cellular clones of the RF cells. One out of the four was in CDR1 and could be correlated with loss of antigen-binding activity in three out of the 10 clones. Altogether, these 13 mutations were preferentially targeted to the DGYW motifs and showed preference for CG nucleotides, indicating that they were AID-mediated. By contrast, mutations were not detected among 3700-4000 nucleotides each of the Vlambda, Cmu and GAPDH genes derived from the same RF cell cultures and the cellular clones. Our results thus show that AID may generate point mutations in the rearranged Ig VH during in vitro cell culture of adult-LCLs and that these mutations may be responsible, at least in part, for the known instability and occasional loss of antigen-binding activity of antibody-secreting LCLs.
16944157 Alpha-lipoic acid suppresses the development of collagen-induced arthritis and protects ag 2007 Jan OBJECTIVE: To test the ability of alpha-lipoic acid (LA) to attenuate the development of collagen-induced arthritis (CIA) in mice. METHODS: Mice were divided into three groups and treated with intraperitoneal administration of LA (10 or 100 mg/kg) or placebo. Clinical, histologic, and biochemical parameters were assessed. Human synovial fibroblasts and peripheral blood mononuclear cells were cocultured in various concentrations of LA to evaluate the effects on osteoclastogenesis. RESULTS: LA was associated with a dose-dependent reduction of CIA, as well as preventing bone erosion and destructive changes. Intracellular reactive oxygen species in lymphocytes obtained from inguinal lymph nodes, which was significantly higher in CIA than control mice, was significantly reduced in CIA by LA. The concentrations of TNF-alpha, IL-1beta, and IL-6 in the paws, and synovial NF-kappaB binding, all of which were markedly higher in CIA than control mice, were reduced by treatment with LA. In addition, LA inhibited the formation of human osteoclasts in vitro. CONCLUSION: Amelioration of joint disease by LA was associated with reduction in oxidative stress, as well as inhibition of inflammatory cytokine activation and NF-kappaB DNA binding activity. Moreover, LA inhibited bone destruction in vivo and osteoclastogenesis in vitro. Collectively, these results indicate that LA may be a new adjunctive therapy for rheumatoid arthritis.
16651620 p21Cip1 is required for the development of monocytes and their response to serum transfer- 2006 May One of the central functions of cyclin-dependent kinase inhibitors, such as p21, p27, or p16, is to prevent entry into the cell cycle. However, the question remains as to whether they have other functions in the cell. We previously demonstrated that overexpression of p21 in fibroblasts isolated from patients with rheumatoid arthritis decreases the production of pro-inflammatory molecules. Overexpression of p21 has been also shown to reduce the development of experimental arthritis in mice and rats. To explore the role of endogenous p21 in the development of arthritis, we induced arthritis in p21(-/-) mice using the K/BxN serum transfer model of arthritis. Mice deficient in p21 were more resistant to serum transfer-induced arthritis (K/BxN) than wild-type (wt) control mice. Fewer macrophages were detected in p21(-/-) as compared to wt joints following transfer of K/BxN serum. Chemotaxis assays of bone marrow-derived macrophages from p21(-/-) and wt mice revealed no difference in migration. However, there was a substantial decrease in inflammatory monocytes circulating in peripheral blood and in monocyte precursors in bone marrow of p21(-/-) mice as compared to wt mice. Adoptive transfer of wt bone marrow-derived macrophages into p21(-/-) mice restored the sensitivity to serum transfer-induced arthritis. These data suggest a novel role for p21 in regulating the development and/or differentiation of monocytic populations that are crucial for the induction of inflammatory arthritis.
15764839 Mechanisms of analgesic action of neurotropin on chronic pain in adjuvant-induced arthriti 2005 Mar Neurotropin((R)), a non-protein extract from the inflamed skin of rabbits inoculated with vaccinia virus, has been clinically used as an analgesic drug for treatment of chronic pain. In this study, we investigated the analgesic mechanisms of Neurotropin in the adjuvant-induced arthritic rat, a chronic pain model with inflammation. Neurotropin caused dose-dependent inhibition of hyperalgesia in the adjuvant-induced arthritic rat after single intravenous (10 - 100 NU/kg) and oral (30 - 200 NU/kg) administration. The analgesic effect of Neurotropin (intravenous 100 NU/kg and oral 200 NU/kg) was significantly inhibited by intrathecal injections of the alpha(2)-adrenoceptor antagonist yohimbine (30 nmol/animal) and the selective 5-HT(3) serotonin receptor antagonist MDL72222 (30 nmol/animal), and slightly inhibited by the non-selective serotonin receptor antagonist methysergide (100 nmol/animal). The results suggest that the analgesic action of Neurotropin is at least in part due to the enhancement of noradrenergic and serotonergic descending pain inhibitory pathways. Neurotropin may be useful for the clinical management of chronic pain diseases such as a rheumatoid arthritis and osteoarthritis.
15693852 Autoimmune hepatitis in primary Sjogren's syndrome: pathological study of the livers and l 2005 Feb Although primary Sjogren's syndrome (pSS) is an autoimmune exocrinopathy, the involvement of liver has been reported. Because no study focusing on autoimmune hepatitis (AIH) in pSS has been published, the purpose of the present study was to perform a clinical and histological examination of the liver, focusing on AIH, in 17 pSS patients. The patients had liver enzyme abnormalities without hepatitis virus infection. In all cases, biopsied livers were examined, and in 10 cases biopsied labial salivary glands were also examined histologically. Based on the authors' diagnostic criteria for AIH in pSS, the liver diseases consisted of AIH (eight cases, 47%), primary biliary cirrhosis (PBC; six cases, 35%), non-specified chronic hepatitis (two cases, 12%) and acute hepatitis (one case, 6%). Lymphoplasmacytic infiltrate, with predominancy of CD3(+) T cells, was noted in both the liver and salivary glands in the patients with AIH. The patients with AIH with severe interface hepatitis had a good response to immunosuppressive therapy. The comparison of liver histology between the PBC with pSS group and the PBC without pSS group showed that the incidence of lymphoid non-suppurative cholangitis was higher in PBC with pSS. In conclusion, the present study offers new information on the relatively common occurrence, diagnostic criteria and treatment effects of AIH in pSS.
16896287 Genomic progress in pediatric arthritis: recent work and future goals. 2006 Sep PURPOSE OF REVIEW: Pediatric arthritis is a heterogeneous group of chronic arthropathies that are influenced by complex genetic and perhaps environmental factors. Interacting genetic traits may one day be identified that provide the basis for predicting disease risk and other characteristics such as course, age of onset, and disease severity. The purpose of this review is to describe the recent progress towards identifying the multiple genes related to pediatric arthritis and understand how they relate to each other and to disease pathology. RECENT FINDINGS: Candidate gene studies are by far the most widely reported type of genetic studies to date for juvenile arthritis with only one genome-wide screen for juvenile rheumatoid/idiopathic arthritis published. Particular attention is paid to studies of candidate genes with potential immunological roles and those associated with other forms of autoimmunity. SUMMARY: Genomic studies may perhaps one day provide information to allow future classification systems of childhood arthritis to include molecular biomarkers as a complement to clinical observations, as well as understand how these genes or proteins relate to each other and to disease pathogenesis.
16207327 Local hyperemia to heating is impaired in secondary Raynaud's phenomenon. 2005 Accurate and sensitive measurement techniques are a key issue in the quantification of the microvascular and endothelial dysfunction in systemic sclerosis (SSc). Thermal hyperemia comprises two separate mechanisms: an initial peak that is axon reflex mediated; and a sustained plateau phase that is nitric oxide dependent. The main objective of our study was to test whether thermal hyperemia in patients with SSc differed from that in patients with primary Raynaud's phenomenon (RP) and healthy controls. In a first study, we enrolled 20 patients suffering from SSc, 20 patients with primary RP and 20 healthy volunteers. All subjects were in a fasting state. Post-occlusive hyperemia, 0.4 mg sublingual nitroglycerin challenge and thermal hyperemia were performed using laser Doppler flowmetry on the distal pad of the third left finger. In a second study, thermal hyperemia was performed in 10 patients with rheumatoid arthritis and 10 patients with primary RP. The thermal hyperemia was dramatically altered in terms of amplitude and kinetics in patients with SSc. Whereas 19 healthy volunteers and 18 patients with primary RP exhibited the classic response, including an initial peak within the first 10 minutes followed by a nadir and a second peak, this occurred only in four of the SSc patients (p < 0.0001). The 10 minutes thermal peak was 43.4 (23.2 to 63), 42.6 (31 to 80.7) and 27 (14.7 to 51.4) mV/mm Hg in the healthy volunteers, primary RP and SSc groups, respectively (p = 0.01), while the 44 degrees C thermal peak was 43.1 (21.3 to 62.1), 42.6 (31.6 to 74.3) and 25.4 (15 to 52.4) mV/mm Hg, respectively (p = 0.01). Thermal hyperemia was more sensitive and specific than post-occlusive hyperhemia for differentiating SSc from primary RP. In patients with rheumatoid arthritis, thermal hyperemia was also altered in terms of amplitude. Thermal hyperemia is dramatically altered in patients with secondary RP in comparison with subjects with primary RP. Further studies are required to determine the mechanisms of this altered response, and whether it may provide additional information in a clinical setting.
16176933 Amelioration of experimental arthritis by a calpain-inhibitory compound: regulation of cyt 2005 Oct Calpain, a calcium-dependent cysteine proteinase, has been reported to participate in the pathophysiology of rheumatoid arthritis (RA). The aim of this study is to investigate the therapeutic efficacy of calpain-inhibitory compounds in an animal model of RA and to clarify the underlying mechanisms in vivo and in vitro. Arthritis was induced in BALB/c mice with anti-type II collagen mAbs and LPS, and the mice were treated intra-peritoneally with a high dose (9 mg kg(-1) per day) or low dose (3 mg kg(-1) per day) of E-64-d (a membrane-permeable cysteine proteinase inhibitor) or control diluent. As a result, a high dose of E-64-d significantly alleviated the clinical arthritis and the histopathological findings, compared with the control diluent, although a low dose of E-64-d did not have a significant effect. Next, we evaluated the effects of E-64-d on cytokine mRNA expression at the inflamed joints by quantitative reverse transcription-PCR. High dose of E-64-d significantly decreased IL-6 and IL-1beta mRNA levels at the inflamed joints. The regulatory effects of E-64-d on cytokine production were also confirmed in vitro, using a synovial cell line (E11) and crude synoviocytes derived from RA patients. These results suggest the key roles of calpain in the pathophysiology of arthritis and that calpain-inhibitory compounds might be applicable to the treatment of arthritic diseases such as RA.