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ID PMID Title PublicationDate abstract
9099991 Analysis of expression of an alternative La (SS-B) cDNA and localization of the encoded N- 1997 Mar 27 A deletion of an (A)-residue was detected in a cDNA encoding for the nuclear autoantigen La/SS-B. The cDNA was recently isolated from a cDNA library made from peripheral blood lymphocytes of a patient with primary Sjögren's Syndrome. The region, where the deletion occurred, represents a hot spot region in the La gene(s). It leads to a frame shift mutation and a premature stop codon eleven amino acids downstream of the deletion site within one of the protease sensitive regions of the La protein. In spite of the frame shift mutation expression of full length La protein occurred efficiently in E. coli. Full length La protein was also made in SF9 cells infected with recombinant baculoviruses, although the efficiency of full length protein production was less. Two major peptides with molecular weights of 29 kDa and 25 kDa were made. The size of these peptides was similar to the known proteolytic degradation products of La protein. The N-terminal 29 kDa fragment containing the RNP consensus sequence located in the cytoplasm. The 25 kDa C-terminal fragment containing the nuclear location signal entered in the nucleus and associated with nuclear speckles. In conclusion, the ability to (i) enter, (ii) remain in the nucleus and (iii) assemble with nuclear speckles resides in the C-terminal domain of La protein and does not depend on the N-terminal RNP-consensus motif.
8993025 TCR in Fas-sensitive T cells from labial salivary glands of patients with Sjögren's syndr 1997 Jan 15 Apoptosis is found in labial salivary glands of patients with Sjogren's syndrome (SS). To analyze the pathogenesis of apoptosis in labial salivary glands of SS patients, we examined the expression of Fas Ag and Fas ligand (FasL) and TCR on T cells susceptible to anti-Fas mAbs (CH-11). Fas Ag is expressed on epithelial cells and mononuclear cells in the salivary glands as observed by an immunohistochemical method. FasL is over-expressed specifically on T cells infiltrating into the labial salivary glands as seen by an reverse transcription-PCR method. These results suggest that apoptosis in SS lips is mediated by a Fas/FasL pathway. PCR single-strand conformation polymorphism (SSCP) clearly demonstrated that more than 40% of the T cells accumulated in labial salivary glands are deleted by incubation with CH-11 for 24 h in vitro, indicating that these expanded cells are Fas sensitive. junctional sequence analysis showed that the same conserved amino acid motifs (LAGG, RLA, SLG, QGPG, PGG, GGE, RGR, KPG, AGD, and MLG) in complementarity determining region 3 (CDR3) are found in Fas-sensitive T cell clones, whereas they are not detected in Fas-resistant clones, suggesting that Fas-sensitive T cells recognize restricted T cell epitopes on autoantigens. In conclusion, the findings suggest that Fas-sensitive T cells in labial salivary glands of SS patients are generated by Ag stimulation and might function as autoreactive T cells.
11592385 Triptolide, a novel diterpenoid triepoxide from Tripterygium wilfordii Hook. f., suppresse 2001 Sep OBJECTIVE: Various extracts of the Chinese herbal remedy Tripterygium wilfordii Hook. f. (TWHF) have been reported to be therapeutically efficacious in rheumatoid arthritis (RA) in China, but their mechanism of action remains unclear. We investigated the effect of triptolide, a diterpenoid triepoxide from TWHF, on the production of pro-matrix metalloproteinase 1 (proMMP-1; or procollagenase 1 or pro-interstitial collagenase 1), proMMP-3 (or prostromelysin 1), tissue inhibitors of metalloproteinases (TIMPs), and proinflammatory cytokines in human synovial fibroblasts and J774A.1 mouse macrophages. METHODS: Human synovial fibroblasts and mouse macrophages were cultured with interleukin-1alpha (IL-1alpha) or lipopolysaccharide (LPS) in the presence or absence of triptolide. The production of proMMPs 1 and 3, TIMPs 1 and 2, cyclooxygenase 1 (COX-1) and COX-2, prostaglandin E2 (PGE2), IL-1beta, and IL-6 was assayed by Western blot analysis and enzyme-linked immunosorbent assay. Gene expression of proMMPs 1 and 3, TIMPs 1 and 2, COX-1 and COX-2, IL-1alpha, IL-1beta, tumor necrosis factor alpha (TNFalpha), and IL-6 was also monitored by Northern blot analysis and reverse transcriptase-polymerase chain reaction. RESULTS: Triptolide suppressed the IL-1alpha-induced production of proMMPs 1 and 3 and decreased their messenger RNA levels in human synovial fibroblasts. In contrast, the IL-1alpha-induced gene expression and production of TIMPs 1 and 2 were further augmented by triptolide in the synovial cells. Triptolide also inhibited the IL-1alpha-induced production of PGE2 by selectively suppressing the gene expression and production of COX-2, but not those of COX-1. In addition, triptolide suppressed the LPS-induced production of PGE2 in mouse macrophages. Furthermore, the gene expression of IL-1alpha, IL-1beta, TNFalpha, and IL-6, as well as the production of IL-1beta and IL-6, were inhibited by triptolide in the LPS-treated mouse macrophages. CONCLUSION: We have demonstrated for the first time that the therapeutic effects of TWHF in RA are due in part to the novel chondroprotective effect of triptolide via the direct suppression of the production of proMMPs 1 and 3 and the simultaneous up-regulation of TIMPs in IL-1-treated synovial fibroblasts. Triptolide's interference with gene expression of proinflammatory cytokines and its known inhibitory effects on PGE2 production are also probably very effective.
11792123 CD40 ligation induces macrophage IL-10 and TNF-alpha production: differential use of the P 2001 Nov 21 Interleukin 10 (IL-10) is an anti-inflammatory cytokine produced in the rheumatoid arthritis (RA) joint by macrophages/monocytes and infiltrating peripheral blood derived lymphocytes. Recent data suggest a role for physical cell-to-cell interactions in the production of IL-10. In this report, we have investigated the signalling mechanisms involved in IL-10 production by peripheral blood-derived macrophages upon interaction with fixed CD40L transfectants. IL-10 and tumour necrosis factor alpha (TNF-alpha) are produced by macrophage colony-stimulating factor (M-CSF)-primed monocytes/macrophages in response to CD40 ligation. The utilization of the inhibitors, wortmannin and LY294002, demonstrated a role for phosphatidylinositol 3-kinase (PI3K) whereas rapamycin demonstrated p70 S6-kinase (p70S6K) involvement in the production of IL-10 by these monocytes. The production of TNF-alpha was enhanced by wortmannin and LY294002, suggesting negative regulation by PI3K; however, it was dependent on p70S6K suggesting a PI3K-independent mechanism of p70S6K activation. One alternative pathway that activates p70S6K independently of PI3K and also differentiates between IL-10 and TNF-alpha is the p42/44 mitogen-activated protein kinase (MAPK), which regulates TNF-alpha production in a PI3K-independent manner. These observations suggest that CD40 ligation induces macrophage IL-10 and TNF-alpha production, the mechanism of which is p70S6K-dependent yet bifurcates at the level of PI3K and p42/44 MAPK.
11719548 Paracrine interactions of chondrocytes and macrophages in cartilage degradation: articular 2001 Nov Cells of the monocyte/macrophage lineage are involved in the development of inflammatory joint diseases such as rheumatoid arthritis. This disease is characterized by cartilage degradation and synovial membrane inflammation with a progressive loss of joint function. The pathological processes are still not well understood. Therefore it would be interesting to develop a suitable experimental in vitro model system for defined studies of monocyte/macrophage and chondrocyte interactions at the molecular level. For that purpose we cocultured chondrocytes from adult human articular cartilage with human monocytes and macrophages for defined periods of time in agarose without addition of serum. We performed zymographic and western blot analysis of culture medium, completed by quantitative RT-PCR of each chondrocyte, monocyte and macrophage RNA, respectively. The reliability of the newly established coculture systems is confirmed by causing a clear decrease of intact aggrecan in the coculture medium plus concurrent appearance of additional smaller fragments and a reduction of chondrocyte aggrecan and collagen II gene expression in the presence of monocytes. In culture medium from cocultures we detected active forms of the matrix metalloproteinases MMP-1, MMP-3 and MMP-9 accompanied by induction of gene expression of MMP-1, membrane type 1 MMP (MT1-MMP) and tissue inhibitor of metalloproteinase 2 (TIMP-2) in chondrocytes. No gene expression of MMP-9 was detectable in chondrocytes, the enzyme was solely expressed in monocytes and macrophages and was downregulated in the presence of chondrocytes. Our results suggest that MMP-9 protein in coculture medium originated from monocytes and macrophages but activation required chondrocyte-derived factors. Because addition of plasmin, a partial activator of pro-MMP-3 and pro-MMP-1, enhanced the activation of pro-MMP-9 and pro-MMP-1 in cocultures but not in monocultured macrophages, and the presence of MMP-3 inhibitor II prevented pro-MMP-9 activation, we assumed a stepwise activation process of pro-MMP-9 that is dependent on the presence of at least MMP-3 and possibly also MMP-1.
11418660 The Sushi domain of soluble IL-15 receptor alpha is essential for binding IL-15 and inhibi 2001 Jul 1 IL-15 is a pleiotropic cytokine that plays important roles in both innate and adaptive immunity. It is associated with a range of immunopathology, including rheumatoid arthritis and allograft rejection. IL-15 functions through the trimeric IL-15R complex, which consists of a high affinity binding alpha-chain and the common IL-2R beta- and gamma-chains. Characterization of IL-15/IL-15R interactions may facilitate the development of improved IL-15 antagonists for therapeutic interventions. We previously constructed soluble murine IL-15Ralpha (sIL-15Ralpha) by deleting the cytoplasmic and transmembrane domains. To localize the functional domain of IL-15Ralpha, we have now constructed various truncated versions of sIL-15Ralpha. The shortest region retaining IL-15 binding activity is a 65-aa sequence spanning the Sushi domain of IL-15Ralpha. Sushi domains, common motifs in protein-protein interactions, contain four cysteines forming two disulfide bonds in a 1-3 and 2-4 pattern. Amino acid substitution of the first or fourth cysteine in sIL-15Ralpha completely abolished its IL-15 binding activity. This also abrogated the ability of sIL-15Ralpha to neutralize IL-15-induced proinflammatory cytokine production and anti-apoptotic response in vitro. Furthermore, the mutant sIL-15Ralpha lost its ability to inhibit carrageenan-induced local inflammation and allogenic cell-induced T cell proliferation and cytokine production in vivo. Thus, the Sushi domain is critical for the functional activity of sIL-15Ralpha.
11345523 Involvement of T-lymphocytes in periodontal disease and in direct and indirect induction o 2001 Periodontal disease is a peripheral infection involving species of gram-negative organisms. T-lymphocytes can be found in the dense inflammatory infiltrate in this disease. CD4+ and CD8+ T-cells are present in periodontal lesions, as are memory/activated T-lymphocytes. In addition, Th1- and Th2-type T-lymphocytes and their associated cytokines with a subtle polarization to Th1 may be present. Th1-type T-cells up-regulate the production of pro-inflammatory cytokines IL-1 and TNF-alpha, which can induce bone resorption indirectly by promoting differentiation of osteoclast precursors and subsequently by activating osteoclasts. Such osteoclast differentiation is dependent on stimulation of osteoprotegerin ligand (OPG-L) production by osteoblastic cells. By contrast, activated T-cells, by virtue of direct production and expression of OPG-L, can directly promote osteoclast differentiation. OPG-L appears to be predominantly expressed on Th1-type cells. The direct and indirect T-cell involvement in periodontal bone resorption appears to be dependent on the degree of Th1-type T-cell recruitment into inflamed gingival tissues. This T-cell recruitment is regulated by adhesion molecules and chemokines/chemokine receptors. The adhesion molecules involved include alpha4 and alpha6 integrins, LFA-1, and ICAM-1. The Th1-type T-cells preferentially express CCR5 and CXCR3, which are found prominently in diseased gingivae. By contrast, little CCR4, expressed by Th2-type T-cells, can be detected. Also, the chemokine ligands RANTES, MIP1-alpha (both CCR5), and IP-10 (CXCR3 ligand) were elevated in inflamed periodontal tissues. The T-cell features in diseased periodontal tissues can be compared with those in rheumatoid arthritis, wherein bone resorption often attributed to Th1-type T-cell involvement has also been demonstrated.
11214480 [What do we know today about diaminodiphenylsulfone?]. 2000 Jul INTRODUCTION: Diaminodiphenylsulfone or dapsone is a chemical analogue of sulfapyridine, synthesized in 1908. Dapsone is a bacteriostatic agent that proved to be efficient in treating leprosy and malaria, but today it is used in treating dermatologic noninfectious inflammatory diseases. PHARMACOLOGY: Dapsone is orally used in a dose of 50-400 mg per day in treatment of dermatologic diseases, and also in a dose of 50-100 mg per day in leprosy treatment. Dapsone is mainly eliminated from the body by urine and smaller part by faeces. Pharmacological interaction was reported when it is used with rifampicin and probenecid. MECHANISM OF ACTION: The bacteriostatic effect of dapsone is well known. It involves inhibition of folic acid synthesis in susceptible organisms. The anti-inflammatory effect of dapsone, which proves to be efficient in treating noninfectious inflammatory diseases, has not been explained completely yet. There are some pieces of evidence that anti-inflammatory action is not connected with its antibacteriological action. CLINICAL USE: Based on previous studies about therapy efficiency of dapsone in treating some diseases, there are two groups of diseases: the group responding well to dapsone (leprosy, malaria, DH, linear IgA-dermatosis, erythema elevatum diutinum, bullous systemic lupus erythematosus) and a group responding with average good response to dapsone (pyoderma gangrenosum, bullous and cicatricial pemphigoid, acne conglobata, discoid cutaneous lupus erythematosus, subcorneal pustulosis dermatosis, granuloma faciale, rheumatoid arthritis, polychondritis, leucocytoclastic vasculitis). ADVERSE EFFECTS: Adverse effects depend on the dose and they rarely occur at doses less than 100 mg per day. They are mainly shown on skin, nervous system, digestive system, hepatobiliary system, and kidney and hematologic system. The most important adverse effects are hemolytic anaemia and methemoglobinemia. Hemolysis usually occurs at doses of 200 mg and more per day. In patients with glucose-6-phosphate dehydrogenase deficiency, hemolysis may be provoked by a dose less than 50 mg per day. For prevention, before using dapsone in therapy, clinical examination with history, blood parameters, liver and renal parameters and determination of glucose-6-phosphate dehydrogenase level are recommended. CONCLUSION: The use of dapsone is absolutely indicated in DH treatment and erythema elevatum diutinum. Because of anti-inflammatory effects, dapsone can also be used in treating other inflammatory noninfectious dermatoses when one should take care about "therapy efficiency/adverse effect" balance using the correct dose, monitoring relevant clinical and laboratory parameters and educating patients.
11197350 Design and synthesis of a multivalent homing device for targeting to murine CD22. 2001 Jan CD22 is a cell-surface glycoprotein uniquely located on mature B-cells and B-cell derived tumour cells. Current evidence suggests that binding of endogenous ligands to CD22 leads to modulation of B-cell activation by antigen. Incidentally, however, B-cell activation may derail. and lead to an undesired immune response, for example in cases of allergy, rheumatoid arthritis and Crohn's disease. In this situation, synthetic high-affinity ligands for CD22 may be of therapeutic value as inhibitors of B-cell activation. Recent studies have revealed that natural ligands for CD22 contain the trisaccharide NeuAc alpha-2,6-Lac as the basic binding motif. In addition, it has been demonstrated that binding to CD22 is strongly enhanced by multivalent presentation of the basic binding motif (cluster effect). In this paper. the stepwise development of a novel multivalent high-affinity ligand for CD22 is described. In the first stage, a series of monovalent NeuAc alpha-2,6-Glc(Y)X type binding motifs was prepared, and their affinity for murine CD22 was monitored, to obtain more insight into the effect of separate structure elements on ligand recognition. In the second stage, we prepared a trivalent cluster, based on the monovalent motif that displayed the highest affinity for CD22, NeuAc alpha-2,6-GlcNBzNO2OMe (7). This cluster, TRIS(NeuAc alpha-2,6-GlcNBzNO2)3 (52), displayed a more than 58-fold higher affinity for CD22 than the reference structure NeuAc alpha-2,6-LacOMe (10). To our knowledge, the cluster 52 is one of the most potent antagonists for CD22 yet synthesised.
11012616 Antigen-induced IL-17 response in the peripheral blood mononuclear cells (PBMC) of healthy 2000 Oct IL-17 is a T cell cytokine with a complex and important role in the immune system. It has been detected in rheumatoid arthritis (RA) synovial membrane and found to stimulate the production of the proinflammatory cytokines IL-6, IL-8, tumour necrosis factor-alpha (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in vitro. To date, there are few data available on the agents that stimulate IL-17 production. We therefore investigated the in vitro IL-17 response to a variety of mitogens and antigens, and compared the IL-17 response to interferon-gamma (IFN-gamma), IL-4, IL-10 and TNF-alpha. In this study we used a type-0 antigen, tetanus toxoid (TT), a type-1 antigen, PPD from Mycobacterium tuberculosis, a potential type-2 rye grass (RG) antigen (Lol I) and an autoantigen SS.B (La), to stimulate PBMC from healthy controls. Cytokine mRNA was measured using semiquantitative reverse transcriptase-polymerase chain reaction and cytokine protein measured using specific ELISA techniques, while the frequency of IL-17-producing T cells was determined by flow cytometry. The mitogens concanavalin A, phytohaemagglutinin and phorbol myristate acetate/ionomycin induced a significant increase in IL-17, with the highest levels being produced by anti-CD3/anti-CD28 stimulation. The antigens TT and PPD significantly increased IL-17 mRNA expression over time, but failed to have such an effect at the protein level. IL-17 protein was also detectable in both antigen-specific (TT, SS. B) and non-specific T cell clones, but at levels lower than IFN-gamma. IL-17 production did not correlate with either the type-1 cytokine IFN-gamma or TNF-alpha or the type-2 cytokine IL-4 or IL-10 at either the mRNA or protein level.
10796384 Analgesia and non-aspirin, non-steroidal anti-inflammatory drugs for osteoarthritis of the 2000 OBJECTIVES: To review all randomized trials of analgesics and anti-inflammatory therapy in osteoarthritis (OA) of the hip. To determine which non-steroidal, anti-inflammatory drug (NSAID) is the most effective, and which NSAID is the most toxic. SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Group's trials register, the Cochrane Controlled Trials Register and Medline up to August 1994. Reference lists of all trials were also manually searched. SELECTION CRITERIA: All randomized controlled trials comparing non-steroidal anti-inflammatory drugs (NSAIDs) and/or analgesics in patients with Osteoarthritis. The trials selected for inclusion were identified by one reviewer (TT) and rechecked by a second (MH). DATA COLLECTION AND ANALYSIS: Qualitative assessments were performed using a quality scoring system designed for NSAID trials in rheumatoid arthritis. Both the design and analysis aspects of the trials were evaluated, each aspect being rated on a scale of 0 to 8. A quantitative method, which calculates the ratio of improvement produced by one NSAID to that produced by another, was used to rate the relative efficacy of different NSAIDs with respect to pain relief. Toxicity comparisons were made according to the reviewer findings. All quality assessments were carried out independently by two reviewers (TT, BS). All data abstraction was carried out by one reviewer (TT) and rechecked by two other reviewers (BS, GW). A consensus was reached on discrepancies. MAIN RESULTS: Forty-three trials were identified, and of these, 39 evaluated NSAIDs, while four evaluated only analgesics. The median design and analysis scores were two and four respectively. Six NSAIDs were included in at least five trials. Of these, indomethacin was rated more effective in five of its seven comparisons, but more toxic in seven of 12 comparisons. Only five of the 29 (17%) NSAID comparisons found statistically significant differences in efficacy. Of the 43 RCTs identified only 17 had statistical data available for future pooling for this meta-analysis. In the case where data was missing, authors of the trials will be contacted for inclusion of data in future reviews. REVIEWER'S CONCLUSIONS: NSAID trials in patients with OA of the hip appear to be weakened by the lack of standardization of case definition of OA, and also by the lack of standardization of outcome assessments. No clear recommendations for the choice of specific NSAID therapy in hip OA can be offered at this time based on this analysis.
10791956 Induction of secreted type IIA phospholipase A2 gene transcription by interleukin-1beta. R 2000 Jul 28 Secreted type IIA phospholipase A(2), which is involved in arachidonic acid release, is abundantly produced by chondrocytes and secreted in the synovial fluids of patients affected by rheumatoid arthritis. Transfection experiments showed that interleukin-1beta stimulates the phospholipase A(2) [-1614; +20] promoter activity by 6-7-fold and that the [-210; -176] fragment is critical for this stimulation. CAAT enhancer-binding protein (C/EBP) beta and C/EBPdelta transcription factors bind to this element as shown by bandshift experiments. Interleukin-1beta increased the levels of C/EBPdelta mRNA as soon as 2 h and up to 24 h without affecting those of C/EBPbeta. Higher amounts of C/EBPdelta proteins correlate with the stimulation of C/EBPdelta mRNA. Mutations or 5' deletions in the upstream [-247; -210] region reduced by 2-fold the basal and interleukin-1beta-stimulated transcription activities. Two types of factors bind to overlapping sequences on this fragment: NF1-like proteins and the glucocorticoid receptor. The glucocorticoid receptor is responsible for a moderate stimulation of the promoter activity by dexamethasone and may interact with C/EBP factors to achieve a full transcription activity in basal conditions and in the presence of interleukin-1beta. A [-114; -85] proximal regulatory element forms three complexes in bandshift experiments, the slowest mobility one involving the Sp1 zinc finger factor. Mutation of this sequence reduced to 2-fold the stimulation of the promoter activity by interleukin-1beta or the C/EBP factors. Induction of the transcription of secreted type IIA phospholipase A(2) gene by interleukin-1beta in chondrocytes absolutely requires C/EBPbeta and C/EBPdelta factors but does not involve NF-kappaB.
10546612 Smoking and joint replacement: resource consumption and short-term outcome. 1999 Oct Smoking has been shown to increase morbidity and mortality in surgical procedures. Microvascular and trauma surgeons have documented the adverse effect of smoking in the healing of skin flaps and increased complication rates in the treatment of nonunions. In addition, spine surgeons have shown the adverse effects of smoking in fusion rates. The objective of this study was to assess the effects of smoking on the incidence of short term complications, resource consumption, and length of hospital stay of patients undergoing arthroplasty of the hip and knee. Two hundred two patients who underwent joint replacement surgery were evaluated. A smoking history was assessed for all patients. The number of packs multiplied by the number of years as a smoker were calculated. Operative and anesthesia time and medical severity of illness were documented on all patients. Short term outcome was assessed using hospital charges, length of stay, inhospital consults, and the presence and number of complications during the acute hospitalization. One hundred forty-one primary and 61 revision procedures were done. The mean age of the patients was 66.07 years. Sixty-one percent of the patients had osteoarthritis, 3.9% had rheumatoid arthritis, 4.9% had osteonecrosis, 28% had a failed total knee or hip arthroplasty and 2% had a periprosthetic fracture. There were 25 patients who smoked and 177 patients who did not smoke. For patients who currently smoke, the mean number of packs of cigarettes smoked per day multiplied by the number of years as a smoker was 28.3. The average length of stay in the hospital was 5.1 days and the average hospital charges were $31,315. Patients who smoked were younger and had fewer comorbidities than patients who did not smoke. However, patients who smoked were found to have statistically longer surgical time and higher charges adjusted for age, procedure, and surgeon than patients who did not smoke. Patients who smoked also had longer anesthesia times. A history of smoking is obtained easily on all patients. Preoperative screening for nicotine use can predict operative time and health resource consumption. The exact reasons why patients who smoked had higher hospital charges remain elusive. Probable reasons include higher degree of operative complexity (orthopaedic severity of illness). In addition patients who smoked previously also had better short term outcome than patients who currently smoke. This indicates the importance of smoking abstinence before joint replacement surgery and other surgical procedures. Regardless of the exact causes, it is more expensive to treat patients who smoke. Contracting for orthopaedic care should include a history of smoking.
9775196 [Aetiologic features of osteoporosis in male patients aged less than 50 years: study of 28 1998 Jul PURPOSE: To study the aetiologic factors of osteoporosis (OP) in young male patients, we conducted a retrospective study of male osteoporosis observed in our department during the past 20 years. METHODS: Patients included in the study were over 16 years of age and had a fracture or a decreased bone mineral density with a T score (assessed at the spine or at the spine and femoral neck) below -2.5 SD. The age and circumstances of diagnosis, serum and 24-hour urinary calcium and phosphorus investigations, hormonal measurements (including parathyroid hormone, thyroid hormones, cortisol and testosterone), bone biopsy and the final diagnosis were analyzed. RESULTS: One hundred and nineteen patients responded to the defined diagnosis criteria. Twenty-eight were less than 50 years of age (group I or young male osteoporosis). Data were compared with those of 30 patients more than 50 years of age (group II). In group I, an aetiology was found in 17 out of 28 cases (60.7%) (secondary osteoporosis: OP II), while 11 out of 28 patients (39.3%) had primary or idiopathic osteoporosis (OP I). In group II, the frequency of OP I was 19 out of 30 cases (63.3%) and 11 out of 30 patients (36.6%) had OP II. However, the frequency of OP II did not differ significantly between the two groups (P = 0.11). The aetiology in group I was either hypogonadism (6 out of 17), alcoholism (2 out of 17), mastocytosis (2 out of 17), primary biliary cirrhosis (1 out of 17), osteogenesis imperfecta (1 out of 17), idiopathic hypercalciuria (1 out of 17), corticosteroid treatment (1 out of 17) or ankylosing spondylitis (1 out of 17). Multiple causes were found in 5 out of 17 cases. The causes of osteoporosis in group II included hypogonadism (2 out of 11), alcoholism (2 out of 11), idiopathic hypercalciuria (2 out of 11), glucocorticosteroid therapy (6 out of 11) and rheumatoid arthritis (1 out of 11). CONCLUSIONS: Our results were compared to those of the various series reported in the literature which, though focusing on male osteoporosis, often included elderly patients. To determine whether osteoporosis in young male is more often OP II, further prospective studies are required.
9667596 Neuronal molecular mimicry in immune-mediated neurologic disease. 1998 Jul Molecular mimicry is implicated in the pathogenesis of autoimmune diseases such as diabetes mellitus, rheumatoid arthritis, and multiple sclerosis (MS). Cellular and antibody-mediated immune responses to shared viral-host antigens have been associated with the development of disease in these patients. Patients infected with human T-lymphotropic virus type I (HTLV-I) develop HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), an immune-mediated disorder of the central nervous system (CNS) that resembles some forms of MS. Damage to neuronal processes in the CNS of HAM/TSP patients is associated with an activated cellular and antibody-mediated immune response. In this study, IgG isolated from HAM/TSP patients was immunoreactive with uninfected neurons and this reactivity was HTLV-I specific. HAM/TSP IgG stained uninfected neurons in human CNS and cell lines but not nonneuronal cells. Neuronal western blots showed IgG reactivity with a single 33-kd band in all HAM/TSP patients tested. By contrast, no neuron-specific IgG reactivity could be demonstrated from HTLV-I seronegative controls and, more important, from HTLV-I seropositive, neurologically asymptomatic individuals. Both immunocytochemical staining and western blot reactivity were abolished by preincubating HAM/TSP IgG with HTLV-I protein lysate but not by control proteins. Staining of CNS tissue by a monoclonal antibody to HTLV-I tax (an immunodominant HTLV-I antigen) mimicked HAM/TSP IgG immunoreactivity. There was no staining by control antibodies. Absorption of HAM/TSP IgG with recombinant HTLV-I tax protein or preincubation of CNS tissue with the monoclonal antibody to HTLV-I tax abrogated the immunocytochemical and western blot reactivity of HAM/TSP IgG. Furthermore, in situ human IgG localized to neurons in HAM/TSP brain but not in normal brain. These data indicate that HAM/TSP patients develop an antibody response that targets uninfected neurons, yet reactivity is blocked by HTLV-I, suggesting viral-specific autoimmune reactivity to the CNS, the damaged target organ in HAM/TSP.
9543089 Leflunomide, a novel immunomodulating agent, prevents the development of allergic sensitiz 1998 Mar BACKGROUND: Leflunomide is a new anti-inflammatory and immunomodulating agent which is showing promise in several immune disorders, especially rheumatoid arthritis. Its activity profile suggests it may be of use in modulating allergic sensitization. OBJECTIVE: To investigate the effectiveness of leflunomide in preventing the development of allergic sensitization. METHODS: Fifty-three brown Norway rats were sensitized by intraperitoneal injection of ovalbumin and adjuvant (ricin) on day 0. To determine the ability of leflunomide to inhibit primary allergic sensitization six rats were treated with A77 1726, the active metabolite of leflunomide, from day 0 through day 5, six were treated from day 5 through day 10, and nine rats acted as controls. On day 14, ovalbumin-specific serum antibody levels and the magnitude of the early-phase airway response (EAR) after inhalation allergen challenge were assessed. To determine the ability of acute topical treatment with leflunomide to inhibit mast cell degranulation, three groups of five animals received either vehicle, 100 microg A77 1726, or 1000 g A77 1726 60 min prior to aerosol allergen challenge. To determine the effects of leflunomide treatment in vivo on mast cell function in vitro, mast cells were obtained by bronchoalveolar lavage from 17 rats (nine treated with leflunomide and eight controls). Allergen-specific and non-specific degranulation (48/80 induced) were studied. RESULTS: In the leflunomide treated rats both ovalbumin-specific IgE and IgG levels were significantly reduced, and the increases in lung resistance and lung elastance were essentially abolished, compared to those of the control group. Non significant differences were found in any of the parameters between the two leflunomide treated groups. Topical pre-treatment with leflunomide did not prevent the allergen-induced EAR. Treatment with leflunomide in vivo prevented allergen-induced mast cell degranulation in vitro because the mast cells lacked IgE on their surface. Non allergen-specific degranulation was normal and allergen-induced degranulation could be restored by passive sensitization. CONCLUSIONS: These data suggests that leflunomide can prevent primary allergic sensitization and prevent allergen-induced EAR by inhibiting production of allergen-specific IgE antibodies. Further studies in atopic conditions are warranted.
9292809 The prevalence of rheumatic diseases in a Filipino urban population: a WHO-ILAR COPCORD St 1997 Sep OBJECTIVE: To determine the point prevalence of musculoskeletal complaints and rheumatic diseases in a Filipino urban community. METHODS: A descriptive cross-sectional 2 phase survey was conducted in an urban community in Metropolitan manila. Phase I (screening) used face-to-face interviews, while phase II (examination) involved case identification of the rheumatic diseases. We sampled 670 households (3065 adults) using a multistage cluster sampling method. A pilot study was conducted to pretest the questionnaire for cross-cultural adaptation and validation, field procedures, sampling design, and data management plan. Standardized translated COPCORD questionnaires (blind translation and blind back-translation) were administered by trained interviewers. Two weeks after Phase I, Phase II was conducted at local health centers. The COPCORD questionnaire screened the number of cases with musculoskeletal complaints. Identification of cases with rheumatic disease was based on American College of Rheumatology (ACR) criteria. RESULTS: Respondents completed 3006 questionnaires (phase I response rate 98%). Of these 489 respondents had musculoskeletal complaints. Functional disability was reported in 25% among these respondents. We examined 353 (phase II response rate 72%), revealing 294 with rheumatic conditions. In 26 persons there were no abnormalities, while 32 had nonrheumatic conditions at examination. The most common rheumatic diseases were osteoarthritis (OA) (n = 124) and soft tissue rheumatism (n = 115). CONCLUSION: The prevalence of musculoskeletal complaints was 16.3% (95% CI 8.6-24.0) of the adult population in a FIlipino urban community. The total prevalence of rheumatic disease is 9.8% (95% CI 8.2-11.4). The prevalence of OA was 4.1% (95% CI 3.3-4.9) and soft tissue rheumatism 3.8% (95% CI 2.9-4.8). The prevalence of rheumatoid arthritis, 0.17% (95% CI 0-9.36), was notably low compared to the prevalence in other developing countries.
11795518 A new function of green tea: prevention of lifestyle-related diseases. 2001 Apr In the normal human life span, there occur lifestyle-related diseases that may be preventable with nontoxic agents. This paper deals with the preventive activity of green tea in some lifestyle-related diseases. Green tea is one of the most practical cancer preventives, as we have shown in various in vitro and in vivo experiments, along with epidemiological studies. Among various biological effects of green tea, we have focused on its inhibitory effect on TNF-alpha gene expression mediated through inhibition of NF-kappaB and AP-1 activation. Based on our recent results with TNF-alpha-deficient mice, TNF-alpha is an endogenous tumor promoter. TNF-alpha is also known to be a central mediator in chronic inflammatory diseases such as rheumatoid arthritis and multiple sclerosis. We therefore hypothesized that green tea might be a preventive agent for chronic inflammatory diseases. To test this hypothesis, TNF-alpha transgenic mice, which overexpress TNF-alpha only in the lungs, were examined. The TNF-alpha transgenic mouse is an animal model of human idiopathic pulmonary fibrosis which also frequently develops lung cancer. Expressions of TNF-alpha and IL-6 were inhibited in the lungs of these mice after treatment with green tea in drinking water for 4 months. In addition, judging from the results of a prospective cohort study in Saitama Prefecture, Japan, green tea helps to prevent cardiovascular disease. In this study, a decreased relative risk of death from cardiovascular disease was found for people consuming over 10 cups of green tea a day, and green tea also had life-prolonging effects on cumulative survival. These data suggest that green tea has preventive effects on both chronic inflammatory diseases and lifestyle-related diseases (including cardiovascular disease and cancer), resulting in prolongation of life span.
11732639 The Ca2+-activated K+ channel of intermediate conductance: a molecular target for novel tr 2001 Dec This review discusses the Ca2+-activated K+ channels of intermediate conductance (IK channels), and their historical discovery in erythrocytes, their classical biophysical characteristics, physiological function, molecular biology as well as their role as possible molecular targets for pharmacological intervention in various diseases. The first described Ca2+-activated K+ channel ever - the so-called Gard6s channel from human erythrocytes--is an IK channel. The "I" denominates the intermediate conductance that distinguishes the IK channels from the related Ca2+-activated K+ channels of small (SK) or large (BK) conductance. The recent cloning of the human IK channel gene (KCNN4) enabled a detailed mapping of the expression in various tissues. IK channel expression is found predominantly in cells of the blood, in epithelia and endothelia. An important physiological role of IK channels is to set the membrane potential at fairly negative values and thereby to build up large electrical gradients for the passive transport of ions such as Cl- efflux driving water and Na+ secretion from epithelia, and Ca2+ influx controlling T-lymphocyte proliferation. The molecular cloning of IK and SK channels has revealed that both channels gain their Ca2+-sensitivity from tightly bound calmodulin (CaM). The IK channel is potently blocked by the scorpion toxin charybdotoxin (ChTx) and the antimycotic clotrimazole (CLT). CLT has been in clinical trials for the treatment of sickle cell disease, diarrhea and ameliorates the symptoms of rheumatoid arthritis. However, inhibition of cytochrome P450 enzymes by CLT limits its therapeutic value, but new drug candidates are entering the stage. It is discussed whether pharmacological modulation of IK channels may be beneficial in sickle cell anemia, cystic fibrosis, secretory diarrhea, craft-versus-host disease and autoimmune diseases.
11705350 Targeting tumor necrosis factor alpha. New drugs used to modulate inflammatory diseases. 2001 Oct Since its discovery, the understanding of the roles for TNF-alpha in human biology and disease has grown. Receptors for TNF are found on virtually all cell types, and many physiologic processes seem to be altered by TNF-alpha. The understanding of how TNF-alpha is involved in the pathophysiology of diseases, such as inflammatory diseases, has allowed the development of new drugs that can interfere with excess TNF-alpha and thus has allowed novel therapies for rheumatoid arthritis and Crohn's disease. As the role of TNF-alpha in other diseases becomes better understood, such TNF-alpha-modulating drugs may find further applications. In the skin, TNF-alpha is prominent cytokine that seems to be important in allergic and irritant contact dermatitis and inflammatory skin conditions. Modulating TNF-alpha activity in the skin may provide therapeutic benefits for a variety of skin conditions (Table 4). Tumor necrosis factor-alpha levels are elevated in skin lesions of psoriasis. A few reports have already suggested that etanercept and infliximab may offer a therapeutic effect in patients with psoriasis. Clinical studies evaluating the true efficacy of these drugs in psoriasis are under way. Specifically, the authors and others are involved in a double-blind, placebo-controlled study to assess the efficacy of etanercept for psoriasis. Thalidomide has been used off-label with some success to treat a number of dermatologic diseases, including several inflammatory skin conditions. Etanercept and infliximab might perhaps prove efficacious for inflammatory skin conditions as well. Finally, it is possible that drugs targeting TNF-alpha may have yet-unrecognized serious side effects. Because TNF-alpha seems to be a central cytokine in UVR-induced apoptosis, the chronic use of TNF-alpha-altering drugs might increase the risk for skin cancers. Tumor necrosis factor-alpha also plays some role in cutaneous wound healing; the effect these drugs might have on this process is also unknown at this time. Certainly, much is already [table: see text] known about TNF-alpha and how it plays many central roles. This understanding has allowed the development of useful new drugs for intractable disease. As the understanding of TNF-alpha and other cytokine biology increases, so will the number of potential therapeutic agents.