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ID PMID Title PublicationDate abstract
17359944 Celecoxib inhibits Na+ currents in rat dorsal root ganglion neurons. 2007 May 7 Celecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor used in the treatment of osteoarthritis and rheumatoid arthritis with fewer gastrointestinal toxicities compared to traditional non-steroidal anti-inflammatory drugs. Voltage-gated Na(+) channels in primary sensory neurons play an important role in the pathogenesis of various pain conditions. We examined the effects of celecoxib on tetrodotoxin-sensitive (TTX-S) and tetrodotoxin-resistant (TTX-R) Na(+) currents in acutely dissociated rat dorsal root ganglion neurons. Celecoxib suppressed both currents in dose- and frequency-dependent manner. The apparent dissociation constants (K(d)) for TTX-S and TTX-R Na(+) currents measured at 0 mV from a holding potential of -80 mV were estimated to be 5.6 and 19.5 microM, respectively. Celecoxib slightly slowed inactivation kinetics of TTX-S Na(+) current, but made it much faster in TTX-R Na(+) current. Celecoxib shifted the activation voltage of TTX-S Na(+) current to a depolarizing direction, but not that of TTX-R Na(+) current. Celecoxib caused a hyperpolarizing shift of the steady-state inactivation curve in both Na(+) currents to a great extent. In addition celecoxib reduced the maximal availability of both Na(+) channels. Thus celecoxib appears to bind to both inactivated and resting Na(+) channels. Celecoxib slowed the recovery of both Na(+) channels from inactivation. All these effects combined would suppress the excitability of sensory neurons. Thus, beside COX-2 inhibition, the Na(+) channel inhibition is considered to contribute to celecoxib analgesia.
17263339 Detection of protein biomarkers using RNA aptamer microarrays and enzymatically amplified 2007 Feb 1 A methodology for the detection of protein biomarkers at picomolar concentrations that utilizes surface plasmon resonance imaging (SPRI) measurements of RNA aptamer microarrays is developed. The adsorption of proteins onto the RNA microarray is detected by the formation of a surface aptamer-protein-antibody complex. The SPRI response signal is then amplified using a localized precipitation reaction catalyzed by the enzyme horseradish peroxidase that is conjugated to the antibody. This enzymatically amplified SPRI methodology is first characterized by the detection of human thrombin at a concentration of 500 fM; the appropriate thrombin aptamer for the sandwich assay is identified from a microarray of three potential thrombin aptamer candidates. The SPRI method is then used to detect the protein vascular endothelial growth factor (VEGF) at a biologically relevant concentration of 1 pM. VEGF is a signaling protein that has been used as a serum biomarker for rheumatoid arthritis, breast cancer, lung cancer, and colorectal cancer and is also associated with age-related macular degeneration.
16885894 [Severe chloroquine- and hydroxychloroquine-induced retinopathy]. 2006 Jun INTRODUCTION: Antimalarial drug-induced retinopathy was first described in the 1950s. Irreversible retinal damage still occurs 50 years later, despite knowledge of the phenomenon. This raises several questions: How aware are physicians of this problem and do they inform their patients? What efficient prevention strategies should be advocated and what are the legal aspects? We present four cases of severe chloroquine- and hydroxychloroquine-induced retinopathy to try to understand what led to these situations. CASE REPORTS: The fist case, a male patient born in 1956, had chloroquine therapy for lupus initiated in 1987, at a dose ranging from 3 to 6 mg/kg per day. In 1992, no toxicity was clinically or electrophysiologically noted. In 1997, macular abnormalities were diagnosed; chloroquine treatment was nevertheless continued. In 2002, the electroretinogram and central visual field examinations were abnormal. Chloroquine treatment was discontinued. In 2005, abnormalities of full-field and multifocal electroretinograms, electro-oculogram, color vision, and visual field confirmed the maculopathy. The second case, a female patient, born in 1956, had chloroquine therapy for rheumatoid arthritis beginning in 1993, at a dose of 5 mg/kg per day. In 1999, 2000, and 2001, electroretinograms were reported as normal. Clinical maculopathy occurred in 2003 and treatment was continued. In January 2004, the central visual field was found abnormal; treatment was discontinued in July 2004. The third case, a female patient born in 1931, had chloroquine therapy for malaria prevention initiated in 1975, at a dose of 1.7 mg/kg per day. No exams were performed after 1983. In 2001, she complained of a left unilateral vision loss. Bilateral maculopathy was clinically found, and confirmed by full-field and multifocal electroretinograms. The fourth case, a female patient born in 1944, had hydroxychloroquine therapy for lupus initiated in 1982 at a dose of 6.9 mg/kg per day. In 2000 and 2002, full-field electroretinograms were reported as normal despite low amplitudes. In 2004, clinical examination was normal, whereas electroretinogram, electro-oculogram, color vision, and central visual field examinations proved severe damage; the treatment was discontinued. DISCUSSION: Retinal damage in these cases was caused by several factors. Treatment was not stopped despite clinically obvious maculopathy in cases 1 and 2. In case 3, no ophthalmologic examinations were performed between 1983 and 2001. In case 4, despite a high cumulative dose, therapy was not discontinued, as also seen in cases 1 and 2, in which ophthalmologic monitoring was not increased. Higher doses than the maximal recommended daily dose occurred in cases 1, 2, and 4. CONCLUSION: Antimalarial drug therapy still requires intensive monitoring to avoid severe retinal damage that can lead to legal blindness. Appropriate examinations should be performed regularly in order to decide whether to taper or stop when damage is still mild, preclinical, or reversible.
16881868 Anti-inflammatory activity of a pteridine derivative (4AZA2096) alleviates TNBS-induced co 2006 Aug Elevated production of tumor necrosis factor (TNF) plays a central role in the pathogenesis of many inflammatory diseases, such as rheumatoid arthritis and Crohn's disease. Naturally occurring pteridine analogs have been reported to have potent immunomodulatory activity, especially on TNF production. The aim of this study is to identify small molecule TNF inhibitiors derived from pteridine and to prove their in vivo efficacy in an inflammatory model. A focused chemical library based on the pteridine scaffold was screened in vitro on lipopolysaccharide (LPS)-induced TNF production in peripheral blood mononuclear cells (PBMC). One synthetic pteridine analog (4AZA2096), shown to have strong inhibitory activity, was selected and tested for its efficacy to treat trinitrobenzenesulfonate (TNBS)-induced colitis in mice, a model of Crohn's disease. Colitis was induced by rectal administration of 1 mg TNBS in 50% ethanol after presensitization via the skin. The synthetic pteridine analog 4AZA2096 was shown to potently inhibit LPS-induced TNF production in vitro. Colitic mice treated with 4AZA2096 orally (20 mg/kg/day) recovered more rapidly and, histologically, had a reduction of inflammatory lesions, less edema, a reduction of goblet cell loss, and reduced wall thickness. Cell infiltration in the colon, especially infiltration of neutrophils, as shown by myeloperoxidase (MPO) activity, was reduced in 4AZA2096-treated animals. Intralesional TNF production was lower in mice of the treated groups, whereas interleukin-18 (IL-18) and interferon-gamma (IFN-gamma) mRNA were not affected. Treatment had no effect on anti-TNBS antibody production, arguing against generalized immunosuppression. In conclusion, we identified a pteridine derivative, 4AZA2096, with strong inhibitory activity on TNF production and a remission- inducing effect in TNBS colitis, supporting further preclinical and clinical development of this novel TNF inhibitor for treatment of inflammatory diseases.
19068145 All-trans retinoic acid suppresses interleukin-6 expression in interleukin-1-stimulated sy 2008 INTRODUCTION: Interleukin-6 (IL-6) is thought to play a pathogenic role in rheumatoid arthritis and synovium is a major source of IL-6 release. We investigated the ability of retinoids to suppress IL-6 expression in IL-1-stimulated synovial fibroblasts, with special care to the contribution of retinoic acid receptor (RAR) and retinoid X receptor (RXR) subtypes, and the implication of the mitogen-activated protein kinase (MAPK) pathway. METHODS: RAR-alpha, -beta, and -gamma and RXR-alpha, -beta, and -gamma levels were determined by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) or Western blot in rat synovial fibroblasts stimulated with 10 ng/mL of IL-1beta. Stimulated levels of IL-6 were assessed by RT-qPCR or immunoassays in the presence or absence of 1 microM all-trans retinoic acid (ATRA) (RAR agonist) or 0.3 microM BMS-649 (RXR agonist). The contribution of RAR subtypes was checked with selective agonists or small interfering RNAs. The effect of ATRA on upstream MAPK (p38 MAPK, c-Jun N-terminal kinase [JNK], and extracellularly regulated kinase 1/2 [ERK1/2]) was assessed by Western blot, and the contribution of the ERK1/2 pathway to the activation of pro-inflammatory transcription factors was studied by TransAm assays. RESULTS: Synovial fibroblasts expressed all RAR and RXR subtypes except RXR-gamma. In IL-1-stimulated cells, ATRA, but not BMS-649, reduced IL-6 expression whereas selective RAR agonists were inactive. The inhibitory effect of ATRA on IL-6 was not affected by the silencing of RAR subtypes. ATRA also reduced the phosphorylation of ERK1/2, but not of p38 MAPK or of JNK. The suppressive effect of ATRA on the activation of activator protein-1 (AP-1) and nuclear factor-IL-6 (NF-IL-6) was reproduced by the MEK1 (mitogen-activated protein extracellularly regulated kinase kinase 1) inhibitor PD-98059, whereas ATRA and PD-98059 had no effect on NF-kappaB activation. CONCLUSIONS: Among RAR and RXR agonists, only ATRA inhibited IL-1-induced IL-6 expression in rat synovial fibroblasts by inhibiting ERK1/2 pathway and subsequent activation of AP-1 and NF-IL-6 independently of RAR.
17546624 Interleukin-4 antagonizes oncostatin M and transforming growth factor beta-induced respons 2008 Feb 1 Oncostatin M (OSM) stimulates cartilage degradation in rheumatoid arthritis (RA) by inducing matrix metalloproteinases (MMPs) and aggrecanases (ADAMTS; a disintegrin and metalloproteinase with thrombospondin motif). Transforming growth factor beta (TGF-beta1) induces cartilage repair in joints but in excessive amounts, promotes inflammation. OSM and TGF-beta1 also induce tissue inhibitor of metalloproteinase-3 (TIMP-3), an important natural inhibitor of MMPs, aggrecanases, and tumor necrosis factor alpha converting enzyme (TACE), the principal proteases involved in arthritic inflammation and cartilage degradation. We studied cartilage protective mechanisms of the antiinflammatory cytokine, interleukin-4 (IL-4). IL-4 strongly (MMP-13 and TIMP-3) or minimally (ADAMTS-4) suppressed OSM-induced gene expression in chondrocytes. IL-4 did not affect OSM-stimulated phosphorylation of extracellular signal-regulated kinases (ERKs), protein 38 (p38), c-Jun N-terminal kinase (JNK) and Stat1. Lack of additional suppression with their inhibitors suggested that MMP-13, ADAMTS-4, and TIMP-3 inhibition was independent of these mediators. IL-4 also downregulated TGF-beta1-induced TIMP-3 gene expression, Smad2, and JNK phosphorylation. Additional suppression of TIMP-3 RNA by JNK inhibitor suggests JNK implication. The cartilage protective effects of IL-4 in animal models of arthritis may be due to its inhibition of MMPs and ADAMTS-4 expression. However, suppression of TIMP-3 suggests caution for using IL-4 as a cartilage protective therapy.
16519819 Analysis of polymorphisms in 16 genes in type 1 diabetes that have been associated with ot 2006 Mar 6 BACKGROUND: The identification of the HLA class II, insulin (INS), CTLA-4 and PTPN22 genes as determinants of type 1 diabetes (T1D) susceptibility indicates that fine tuning of the immune system is centrally involved in disease development. Some genes have been shown to affect several immune-mediated diseases. Therefore, we tested the hypothesis that alleles of susceptibility genes previously associated with other immune-mediated diseases might perturb immune homeostasis, and hence also associate with predisposition to T1D. METHODS: We resequenced and genotyped tag single nucleotide polymorphisms (SNPs) from two genes, CRP and FCER1B, and genotyped 27 disease-associated polymorphisms from thirteen gene regions, namely FCRL3, CFH, SLC9A3R1, PADI4, RUNX1, SPINK5, IL1RN, IL1RA, CARD15, IBD5-locus (including SLC22A4), LAG3, ADAM33 and NFKB1. These genes have been associated previously with susceptibility to a range of immune-mediated diseases including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), Graves' disease (GD), psoriasis, psoriatic arthritis (PA), atopy, asthma, Crohn disease and multiple sclerosis (MS). Our T1D collections are divided into three sample subsets, consisting of set 1 families (up to 754 families), set 2 families (up to 743 families), and a case-control collection (ranging from 1,500 to 4,400 cases and 1,500 to 4,600 controls). Each SNP was genotyped in one or more of these subsets. Our study typically had approximately 80% statistical power for a minor allele frequency (MAF) >5% and odds ratios (OR) of 1.5 with the type 1 error rate, alpha = 0.05. RESULTS: We found no evidence of association with T1D at most of the loci studied 0.02

16846524 Autoantibodies against the replication protein A complex in systemic lupus erythematosus a 2006 Replication protein A (RPA), a heterotrimer with subunits of molecular masses 70, 32, and 14 kDa, is a single-stranded-DNA-binding factor involved in DNA replication, repair, and recombination. There have been only three reported cases of anti-RPA in systemic lupus erythematosus (SLE) and Sjögren syndrome (SjS). This study sought to clarify the clinical significance of autoantibodies against RPA. Sera from 1,119 patients enrolled during the period 2000 to 2005 were screened by immunoprecipitation (IP) of 35S-labeled K562 cell extract. Antigen-capture ELISA with anti-RPA32 mAb, immunofluorescent antinuclear antibodies (ANA) and western blot analysis with purified RPA were also performed. Our results show that nine sera immunoprecipitated the RPA70-RPA32-RPA14 complex and all were strongly positive by ELISA (titers 1:62,500 to 1:312,500). No additional sera were positive by ELISA and subsequently confirmed by IP or western blotting. All sera showed fine speckled/homogeneous nuclear staining. Anti-RPA was found in 1.4% (4/276) of SLE and 2.5% (1/40) of SjS sera, but not in rheumatoid arthritis (0/35), systemic sclerosis (0/47), or polymyositis/dermatomyositis (0/43). Eight of nine patients were female and there was no racial predilection. Other positive patients had interstitial lung disease, autoimmune thyroiditis/hepatitis C virus/pernicious anemia, or an unknown diagnosis. Autoantibody specificities found in up to 40% of SLE and other diseases, such as anti-nRNP, anti-Sm, anti-Ro, and anti-La, were unusual in anti-RPA-positive sera. Only one of nine had anti-Ro, and zero of nine had anti-nRNP, anti-Sm, anti-La, or anti-ribosomal P antibodies. In summary, high titers of anti-RPA antibodies were found in nine patients (1.4% of SLE and other diseases). Other autoantibodies found in SLE were rare in this subset, suggesting that patients with anti-RPA may form a unique clinical and immunological subset.
18509540 Effective detection of human leukocyte antigen risk alleles in celiac disease using tag si 2008 May 28 BACKGROUND: The HLA genes, located in the MHC region on chromosome 6p21.3, play an important role in many autoimmune disorders, such as celiac disease (CD), type 1 diabetes (T1D), rheumatoid arthritis, multiple sclerosis, psoriasis and others. Known HLA variants that confer risk to CD, for example, include DQA1*05/DQB1*02 (DQ2.5) and DQA1*03/DQB1*0302 (DQ8). To diagnose the majority of CD patients and to study disease susceptibility and progression, typing these strongly associated HLA risk factors is of utmost importance. However, current genotyping methods for HLA risk factors involve many reactions, and are complicated and expensive. We sought a simple experimental approach using tagging SNPs that predict the CD-associated HLA risk factors. METHODOLOGY: Our tagging approach exploits linkage disequilibrium between single nucleotide polymorphism (SNPs) and the CD-associated HLA risk factors DQ2.5 and DQ8 that indicate direct risk, and DQA1*0201/DQB1*0202 (DQ2.2) and DQA1*0505/DQB1*0301 (DQ7) that attribute to the risk of DQ2.5 to CD. To evaluate the predictive power of this approach, we performed an empirical comparison of the predicted DQ types, based on these six tag SNPs, with those executed with current validated laboratory typing methods of the HLA-DQA1 and -DQB1 genes in three large cohorts. The results were validated in three European celiac populations. CONCLUSION: Using this method, only six SNPs were needed to predict the risk types carried by >95% of CD patients. We determined that for this tagging approach the sensitivity was >0.991, specificity >0.996 and the predictive value >0.948. Our results show that this tag SNP method is very accurate and provides an excellent basis for population screening for CD. This method is broadly applicable in European populations.
18465055 Higher prevalence of gastrointestinal symptoms among patients with rheumatic disorders. 2008 May INTRODUCTION: Chronic disorders, such as rheumatic disorders, are associated with increased gastrointestinal (GI) complaints. Medications may be a contributory factor. This study assessed the prevalence of GI symptoms among patients followed-up in a rheumatology clinic. METHODS: Enquiries about GI, psychological and psychosomatic symptoms (headache, insomnia, anxiety, backache and depression) were made from patients. Non-related visitors served as the control group. The underlying disorders were rheumatoid arthritis (RA, 37 percent), systemic lupus erythromatosus (SLE, 23 percent) and others (40 percent). RESULTS: The symptom prevalence of the following complaints were: reduced appetite (10.2 percent), nausea (20.2 percent), vomiting (10.7 percent), dysphagia (7.3 percent), odynophagia (5.1 percent), early satiety (27.5 percent), heartburn (15.2 percent), dyspepsia (44.6 percent), abdominal bloating (20.8 percent) and irregular bowel habit (6.7 percent). There were no differences between the various rheumatic disorders (RA/SLE and RA/others) except for more heartburn in SLE compared to others (p-value is less than 0.05). There was no significant difference between nonsteroidal anti-inflammatory drug (NSAID) users and non-users. Patients on medications with GI (disease modifying/steroid/NSAIDs) adverse effects, experienced a higher rate of early satiety (odds-ratio [OR] 3.5, 95 percent confidence interval [CI] 1.4-8.9) and dyspepsia (OR 2.1, 95 percent CI 1.2-4.3). Compared to the control group, patients had more GI symptoms (all p-values are less than 0.05) except for irregular bowel habits. Patients also experienced more anxiety (OR 2.1, 95 percent CI 1.1-2.4) and backache (OR 2.6, 95 percent CI 1.6-4.2), and had significantly higher symptom clustering (more than two symptoms) compared to the controls (p-value is less than 0.001). CONCLUSION: GI symptoms are common among patients with rheumatic disorders. Medications alone do not account for the high prevalence, suggesting that the underlying conditions predispose to GI symptoms.
18292575 Etk/BMX, a Btk family tyrosine kinase, and Mal contribute to the cross-talk between MyD88 2008 Mar 1 MyD88 and focal adhesion kinase (FAK) are key adaptors involved in signaling downstream of TLR2, TLR4, and integrin alpha5beta1, linking pathogen-associated molecule detection to the initiation of proinflammatory response. The MyD88 and integrin pathways are interlinked, but the mechanism of this cross-talk is not yet understood. In this study we addressed the involvement of Etk, which belongs to the Tec family of tyrosine kinases, in the cross-talk between the integrin/FAK and the MyD88 pathways in fibroblast-like synoviocytes (FLS) and in IL-6 synthesis. Using small interfering RNA blockade, we report that Etk plays a major role in LPS- and protein I/II (a model activator of FAK)-dependent IL-6 release by activated FLS. Etk is associated with MyD88, FAK, and Mal as shown by coimmunoprecipitation. Interestingly, knockdown of Mal appreciably inhibited IL-6 synthesis in response to LPS and protein I/II. Our results also indicate that LPS and protein I/II induced phosphorylation of Etk and Mal in rheumatoid arthritis FLS via a FAK-dependent pathway. In conclusion, our data provide support that, in FLS, Etk and Mal are implicated in the cross-talk between FAK and MyD88 and that their being brought into play is clearly dependent on FAK.
17988193 Osteopontin small interfering RNA protects mice from fulminant hepatitis. 2007 Dec Osteopontin (OPN) has been implicated in various helper T cell type 1 immunity-mediated diseases including rheumatoid arthritis (RA), multiple sclerosis (MS), Crohn's disease, and fulminant hepatitis. Increased expression of OPN has been detected in pathological foci of these diseases. RA and fulminant hepatitis have been successfully treated by administration of neutralizing anti-OPN antibody in mice. Antibody treatment may elicit side effects including allergic reactions against heterologous antibody proteins, thus necessitating humanization of antibody. To provide alternative means to neutralize OPN function, in this study we explored the possibility of using OPN small interfering RNA (siRNA) to silence OPN gene expression. In vitro, OPN siRNA efficiently silenced the expression of both exogenous and endogenous OPN gene. After hydrodynamic intravenous injection of OPN siRNA, OPN siRNA was efficiently delivered to the liver, which resulted in the efficient silencing of OPN gene expression in liver. In a murine model of concanavalin A (ConA)-induced fulminant hepatitis, OPN expression was elevated in liver and severe hepatic necrosis was induced. Importantly, after OPN siRNA treatment, the OPN expression level in liver was significantly reduced and liver tissue injury was ameliorated, as reflected by the significant reduction of serum alanine aminotransferase levels and almost normal liver histology. Thus, this study indicates that OPN siRNA delivery has therapeutic potential in various inflammatory diseases in which OPN play a critical role by silencing OPN gene expression in vivo.
20641847 (111)In-Tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-Glu-[cyclo(Arg-Gly-Asp-D-Phe- 2004 Integrins are a family of heterodimeric glycoproteins on cell surfaces that mediate diverse biological events involving cell–cell and cell–matrix interactions (1). Integrins consist of an α and a β subunit and are important for cell adhesion and signal transduction. The α(v)β(3) integrin is the most prominent receptor affecting tumor growth, tumor invasiveness, metastasis, tumor-induced angiogenesis, inflammation, osteoporosis, and rheumatoid arthritis (2-7). Expression of the α(v)β(3) integrin is strong on tumor cells and activated endothelial cells, whereas expression is weak on resting endothelial cells and most normal tissues. Antagonists of α(v)β(3) are being studied as antitumor and antiangiogenic agents, and the agonists of α(v)β(3) are being studied as angiogenic agents for coronary angiogenesis (6, 8, 9). Extracellular matrix proteins (vitronectin, fibrinogen, laminin, and collagen) contain a tripeptide sequence consisting of Arg-Gly-Asp (RGD), which binds to a variety of integrins, including α(v)β(3). Various radiolabeled antagonists have been introduced for imaging of tumors and tumor angiogenesis (10). Most cyclic RGD peptides are composed of five amino acids. Haubner et al. (11) reported that various cyclic RGD peptides exhibit selective inhibition of binding to α(v)β(3) (inhibition concentration (IC(50)), 7–40 nM) but not to integrins α(v)β(5) (IC(50), 600–4,000 nM) or α(IIb)β(3) (IC(50), 700–5,000 nM). Various radiolabeled cyclic RGD peptides have been found to have high accumulation in tumors in nude mice (12). Janssen et al. (13) reported the development of (111)In-tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid-Glu-[cyclo(Arg-Gly-Asp-D-Phe-Lys)](2) ((111)In-DOTA-E-[c(RGDfK)](2)) for imaging α(v)β(3) receptors in nude mice bearing ovarian carcinoma tumors.
20641670 (99m)Tc-Hydrazinonicotinic acid-Glu-{Glu-[cyclo(Arg-Gly-Asp-D-Phe-Lys)](2)}(2). 2004 Integrins are a family of heterodimeric glycoproteins on cell surfaces that mediate diverse biological events involving cell-cell and cell-matrix interactions (1). Integrins consist of an α and a β subunit and are important for cell adhesion and signal transduction. α(v)β(3) integrin is the most prominent receptor affecting tumor growth, tumor invasiveness, metastasis, tumor-induced angiogenesis, inflammation, osteoporosis, and rheumatoid arthritis (2-7). Expression of α(v)β(3) integrin is strong on tumor cells and activated endothelial cells, whereas expression is weak on resting endothelial cells and most normal tissues. α(v)β(3) antagonists are being studied as antitumor and antiangiogenic agents and the agonists as angiogenic agents for coronary angiogenesis (6, 8, 9). Extracellular matrix proteins (vitronectin, fibrinogen, laminin, and collagen) contain a tripeptide sequence consisting of Arg-Gly-Asp (RGD), which binds to a variety of integrins, including α(v)β(3). Various radiolabeled antagonists have been introduced for imaging of tumors and tumor angiogenesis (10). Most of the cyclic RGD peptides are composed of five amino acids. Haubner et al. (11) reported that various cyclic RGD peptides exhibit selective inhibition of binding to α(v)β(3) (IC(50), 7-40 nM) but not to α(v)β(5) (IC(50), 600-4,000 nM) or α(IIb)β(3) (IC(50), 700-5,000 nM) integrins. Various radiolabeled cyclic RGD peptides have been found to have high accumulation in tumors in nude mice (12). Hydrazinonicotinic acid (HYNIC) is a coupling agent for (99m)Tc labeling of peptides that can achieve high specific activities without affecting receptor-binding ability of the amino acid sequence. Liu et al. (13) reported the success of radiolabeling cylco(Arg-Gly-Asp-D-Phe-Lys) (c(RGDfK)) tetramer linked by glutamic acid that was conjugated with HYNIC. Trisodium triphenylphosphine-3,3’,3’’-trisulfonate (TPPTS) and tris(hydroxymethyl)-methylglycine (tricine) were used as coligands. (99m)Tc-HYNIC-E{E[c(RGDfK)](2)}(2)(tricine)(TPPTS) showed high tumor accumulation in nude mice bearing human tumor xenografts.
17640966 Activation of interleukin-1 signaling cascades in normal and osteoarthritic articular cart 2007 Sep Interleukin (IL)-1 is one of the most important catabolic cytokines in rheumatoid arthritis. In this study, we were interested in whether we could identify IL-1 expression and activity within normal and osteoarthritic cartilage. mRNA expression of IL-1beta and of one of its major target genes, IL-6, was observed at very low levels in normal cartilage, whereas only a minor up-regulation of these cytokines was noted in osteoarthritic cartilage, suggesting that IL-1 signaling is not a major event in osteoarthritis. However, immunolocalization of central mediators involved in IL-1 signaling pathways [38-kd protein kinases, phospho (P)-38-kd protein kinases, extracellular signal-regulated kinase 1/2, P-extracellular signal-regulated kinase 1/2, c-Jun NH(2)-terminal kinase 1/2, P-c-Jun NH(2)-terminal kinase 1/2, and nuclear factor kappaB] showed that the four IL-1 signaling cascades are functional in normal and osteoarthritic articular chondrocytes. In vivo, we found that IL-1 expression and signaling mechanisms were detectible in the upper zones of normal cartilage, whereas these observations were more pronounced in the upper portions of osteoarthritic cartilage. Given these expression and distribution patterns, our data support two roles for IL-1 in the pathophysiology of articular cartilage. First, chondrocytes in the upper zone of osteoarthritic articular cartilage seem to activate catabolic signaling pathways that may be in response to diffusion of external IL-1 from the synovial fluid. Second, IL-1 seems to be involved in normal cartilage tissue homeostasis as shown by identification of baseline expression patterns and signaling cascade activation.
17395661 Renal involvement in systemic amyloidosis--an Italian retrospective study on epidemiologic 2007 Jun BACKGROUND: Few data are available on epidemiology and clinical picture of renal involvement in different forms of systemic amyloidosis. METHODS: Patients with biopsy-proven systemic amyloidosis diagnosed in Italy between January 1995 and December 2000 were selected from 49 Nephrology and Internal Medicine Units provided they showed signs characteristic of renal involvement. Clinical and laboratory information were collected by using a specific data form for diagnosis integrated by a questionnaire on diagnostic tools. Collected data were matched both with the Italian Registry of Renal Biopsies (IRRB) and the Registry of the Italian Society of Amyloidosis (SIA) in order to approximate the incidence of the disease. RESULTS: Of all patients, 373 were finally selected throughout Italy with an estimated mean incidence of renal amyloidosis of 2.1 per million population (p.m.p.) per year. Of those, 237 were affected from AL (primary) amyloidosis, 104 from AA (secondary) amyloidosis and 6 from AF (heredofamilial) forms. In 26 cases the type of amyloidosis remained undetermined. Among patients with AL, 36 presented an associated multiple myeloma (MM). Rheumatoid arthritis (RA) was the commonest underlying disease in AA. Median age ranged between 63 and 65 years in all groups. Males were prevalent in AL and females in AA. The main clinical features of renal involvement were represented by nephrotic syndrome and renal failure observed in 59 and 54% of cases, respectively. The presence of a lambda light chain, either in serum or urine was significantly associated to a more elevated urinary protein loss and to a reduced renal function. Patients with AA showed a worse renal function at presentation than patients with AL, possibly due to a late diagnosis and/or referral to nephrology units. Diagnosis was obtained by renal biopsy in 315 cases, by abdominal fat tissue (AFT) aspiration/biopsy in 156 patients and by other organ biopsies in 47 patients. Characterization of deposits was extremely variable among referring centres. CONCLUSIONS: Our results point to an increased incidence of renal amyloidosis observed in Italy over the period 1996-2000 with AL as the prevalent type. Characterization of amyloid deposits still remains the major diagnostic challenge of the disease. The institution of networks dedicated to rare diseases is strongly recommended in order to effectively afford this challenge.
17077019 [The abnormality of FcgammaRIIB1-mediated signaling and the hyperactivity of B cells from 2006 Nov AIM: To evaluate the effect of FcgammaRIIB(1) (CD32) representative self-inhibitory adjustive mechanism of B cells on pathogenesis of systemic lupus erythematosus (SLE) by observing the expression characteristic and functional state of molecules on the surface of B cells from SLE patients. METHODS: The peripheral blood mononuclear cells (PBMC) were prepared by density gradient centrifugation, and the B cells were isolated from PBMC by magnetic activated cell sorting (MACS). The fluxes of intracytoplasmic calcium ([Ca(2+)](i)) of B cells activated by different activators were measured by fluorescence spectrophotometric method. The IgG production by B cells cultured with activators was assayed by ELISA. The expression levels of CD32, CD19, and IgM on the surface of B cells were measured by flow cytometry. RESULTS: (1)After B cells were stimulated with goat anti-human mu chain F(ab')(2) fragments and whole IgG respectively, the ratio of [Ca(2+)](i) response by F(ab')(2) fragments to whole IgG was significantly lower in SLE B cells compared to rheumatoid arthritis (RA)(P<0.05) or normal (P<0.01) B cells. (2)The ratio of total IgG production by B cells cultured with staphylococcal protein A (SPA) to SPA plus IgG anti-mu chain was significantly lower in SLE patients compared to RA patients or normal individuals (P<0.05). (3)There was no obvious difference in the expression of CD19, CD32, and IgM on the surface of B cells from SLE, RA patients and normal individuals (P>0.05). CONCLUSION: The inhibitory signaling abnormality of CD32 possibly contributes to the mechanism of hyperactivity of human SLE B cells.
16984135 Delivery of the p38 MAPkinase inhibitor SB202190 to angiogenic endothelial cells: developm 2006 Sep Endothelial cells play an important role in inflammatory disorders, as they control the recruitment of leukocytes into inflamed tissue and the formation of new blood vessels. Activation of p38MAP kinase results in the production of proinflammatory cytokines and the expression of adhesion molecules. P38MAP kinase inhibitors are therefore considered important candidates for the treatment of inflammatory disorders. In the present study, we propose a novel strategy to counteract these processes by delivery of the p38MAP kinase inhibitor SB202190 into angiogenic endothelial cells. A drug-targeting conjugate was developed by conjugation of SB202190 to human serum albumin (HSA) using a novel platinum-based linker. Specificity for angiogenic endothelial cells was introduced by conjugation of cyclic RGD-peptides via bifunctional polyethylene glycol linkers. The final products contained an average of nine SB202190 and six RGDPEG groups per albumin. The platinum-based linker displayed high stability in buffers and culture medium, but released SB202190 slowly upon competition with sulfur-containing ligands like glutathione. RGDPEG-SB-HSA bound to alpha(v3)-integrin expressing endothelial cells (human umbilical cord vein endothelial cells) with low nanomolar affinity and was subsequently internalized. When HUVEC were treated with TNF to induce inflammatory events, pretreatment with RGDPEG-SB-HSA partially inhibited proinflammatory gene expression (IL-8, E-selectin; 30% inhibition) and secretion of cytokines (IL-8, 34% inhibition). We conclude that the developed RGDPEG-SB-HSA conjugates provide a novel means to counteract inflammation disorders such as rheumatoid arthritis.
16918914 Stochastic search gene suggestion: a Bayesian hierarchical model for gene mapping. 2006 Jun Mapping the genes for a complex disease, such as diabetes or rheumatoid arthritis (RA), involves finding multiple genetic loci that may contribute to the onset of the disease. Pairwise testing of the loci leads to the problem of multiple testing. Looking at haplotypes, or linear sets of loci, avoids multiple tests but results in a contingency table with sparse counts, especially when using marker loci with multiple alleles. We propose a hierarchical Bayesian model for case-parent triad data that uses a conditional logistic regression likelihood to model the probability of transmission to a diseased child. We define hierarchical prior distributions on the allele main effects to model the genetic dependencies present in the human leukocyte antigen (HLA) region of chromosome 6. First, we add a hierarchical level for model selection that accounts for both locus and allele selection. This allows us to cast the problem of identifying genetic loci relevant to the disease into a problem of Bayesian variable selection. Second, we attempt to include linkage disequilibrium as a covariance structure in the prior for model coefficients. We evaluate the performance of the procedure with some simulated examples and then apply our procedure to identifying genetic markers in the HLA region that influence risk for RA. Our software is available on the website http://www.epigenetic.org/Linkage/ssgs-public/.
19203472 Evolution of nonsteroidal anti-inflammatory drugs (NSAIDs): cyclooxygenase (COX) inhibitio 2008 Sep 20 PURPOSE: NSAIDs constitute an important class of drugs with therapeutic applications that have spanned several centuries. Treatment of inflammatory conditions such as rheumatoid arthritis (RA) and osteoarthritis (OA) starting from the classic drug aspirin to the recent rise and fall of selective COX-2 inhibitors has provided an enthralling evolution. Efforts to discover an ultimate magic bullet to treat inflammation continues to be an important drug design challenge. This review traces the origins of NSAIDs, their mechanism of action at the molecular level such as cyclooxygenase (COX) inhibition, development of selective COX-2 inhibitors, their adverse cardiovascular effects, and some recent developments targeted to the design of effective anti-inflammatory agents with reduced side effects. METHODS: Literature data is presented describing important discoveries pertaining to the sequential development of classical NSAIDs and then selective COX-2 inhibitors, their mechanism of action, the structural basis for COX inhibition, and recent discoveries. RESULTS: A brief history of the development of NSAIDs and the market withdrawal of selective COX-2 inhibitors is explained, followed by the description of prostaglandin biosynthesis, COX isoforms, structure and function. The structural basis for COX-1 and COX-2 inhibition is described along with methods used to evaluate COX-1/COX-2 inhibition. This is followed by a section that encompasses the major chemical classes of selective COX-2 inhibitors. The final section describes briefly some of the recent advances toward developing effective anti-inflammatory agents such as nitric oxide donor NO-NSAIDs, dual COX/LOX inhibitors and anti-TNF therapy. CONCLUSIONS: A great deal of progress has been made toward developing novel anti-inflammatory agents. In spite of the tremendous advances in the last decade, the design and development of a safe, effective and economical therapy for treating inflammatory conditions still presents a major challenge.