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ID PMID Title PublicationDate abstract
10651658 Pharmacoepidemiology of non-steroidal anti-inflammatory drug use in Nottingham general pra 2000 Feb AIM: To investigate the pharmacoepidemiology of NSAID usage in Nottingham general practices. DESIGN: Questionnaire sent to 1137 consecutive recipients of an NSAID prescription from 21 doctors in six general practices with computerized records. Patient responses were subsequently linked to data held on the practice records. SETTING: General practices in and around Nottingham, selected to reflect local variations in number of partners, list size, geographical location, deprivation, prescribing burden and prescribing rate. SUBJECTS: Unselected patients receiving NSAIDs prescribed for all indications. MAIN OUTCOME MEASURES: Indication for treatment, differences in prescribing to different age groups, compliance and overall scheme drug exposure, drug effectiveness and tolerability, possible drug-related adverse events, patients' overall satisfaction with treatment and estimated costs of care. RESULTS: NSAIDs were used for a wide range of conditions and only a small number of patients had rheumatoid arthritis. The main drugs used were ibuprofen, diclofenac and naproxen. Patients making short-term use of NSAIDs had low compliance if they experienced adverse drug effects, whilst conversely in long-term users, those with high compliance reported more adverse drug effects. Calculated compliance did not vary with age although older patients (over 65 years) claimed in their questionnaires to be more compliant than younger patients. Half the patients reported good or complete symptom relief. Half of those questions (and two thirds of those with good or complete symptom relief) rated their NSAID as the best treatment they had received for their current condition. The frequency of gastrointestinal adverse events was higher in the young and the old, which correlated with the use of anti-ulcer drugs, and increased with the total number of medications used. CONCLUSIONS: NSAIDs are used for a wide-range of conditions. They give symptom relief to, and are perceived as effective by, most patients taking them.
10567385 Overexpression of cyclooxygenase-2 induces cell cycle arrest. Evidence for a prostaglandin 1999 Nov 26 The immediate-early gene cyclooxygenase 2 (Cox-2) is induced in a variety of hyperplastic pathological conditions, including rheumatoid arthritis and colorectal cancer. Although a causal role for Cox-2 has been proposed, mechanisms by which Cox-2 function contributes to the pathogenesis of hyperplastic disease are not well defined. We constructed a green fluorescent protein-tagged Cox-2 (Cox-2-GFP) to examine its effects on a variety of cell types upon overexpression. Subcellular localization and enzymatic and pharmacological properties of Cox-2-GFP polypeptide were indistinguishable from those of the wild-type Cox-2 polypeptide. Overexpression of the Cox-2-GFP or the Cox-2 polypeptide by transient transfection suppressed the population of cells in the S phase of the cell cycle, with a concomitant increase in G(0)/G(1) population. In contrast, transient overexpression of GFP had no effect on cell cycle distribution, whereas endoplasmic reticulum-retained GFP (GFP-KDEL) overexpression was associated with only a minor decrease of cells in S phase. Interestingly, neither NS-398 (a Cox-2-specific inhibitor) nor indomethacin could reverse the effect of Cox-2-GFP overexpression on cell cycle progression. Furthermore, two mutants of Cox-2, S516Q and S516M, which lack the cyclooxygenase activity, exhibited the same effect as Cox-2-GFP. The cell cycle effect of Cox-2-GFP was observed in ECV-304, NIH 3T3, COS-7, bovine microvascular endothelial cells, and human embryonic kidney 293 cells. These findings suggest that Cox-2 inhibits cell cycle progression in a variety of cell types by a novel mechanism that does not require the synthesis of prostaglandins.
10479650 Peroxisome proliferator-activated receptor activators target human endothelial cells to in 1999 Sep An early event in acute and chronic inflammation and associated diseases such as atherosclerosis and rheumatoid arthritis is the induced expression of specific adhesion molecules on the surface of endothelial cells (ECs), which subsequently bind leukocytes. Peroxisome proliferator-activated receptors (PPARs), members of the nuclear receptor superfamily of transcription factors, are activated by fatty acid metabolites, peroxisome proliferators, and thiazolidinediones and are now recognized as important mediators in the inflammatory response. Whether PPAR activators influence the inflammatory responses of ECs is unknown. We show that the PPAR activators 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)), Wyeth 14643, ciglitazone, and troglitazone, but not BRL 49653, partially inhibit the induced expression of vascular cell adhesion molecule-1 (VCAM-1), as measured by ELISA, and monocyte binding to human aortic endothelial cells (HAECs) activated by phorbol 12-myristate 13-acetate (PMA) or lipopolysaccharide. The "natural" PPAR activator 15d-PGJ(2) had the greatest potency and was the only tested molecule capable of partially inhibiting the induced expression of E-selectin and neutrophil-like HL60 cell binding to PMA-activated HAECs. Intracellular adhesion molecule-1 induction by PMA was unaffected by any of the molecules tested. Both PPAR-alpha and PPAR-gamma mRNAs were detected in HAECs by using reverse transcription-polymerase chain reaction and a ribonuclease protection assay; however, we have yet to determine which, if any, of the PPARs are mediating this process. These results suggest that certain PPAR activators may help limit chronic inflammation mediated by VCAM-1 and monocytes without affecting acute inflammation mediated by E-selectin and neutrophil binding.
10391542 Rates of revision knee replacement in Ontario, Canada. 1999 Jun BACKGROUND: The present study was designed to measure the longevity of knee replacements and to assess the determinants of revision knee replacements in order to enhance the potential for informed decision-making. METHODS: Data on all hospitalizations for knee replacement that occurred in Ontario, Canada, between April 1, 1984, and March 31, 1991, were acquired. To calculate the rates of revision knee replacement, two algorithms were developed: one distinguished primary knee replacements from revision knee replacements, and the second linked revision knee replacements to primary knee replacements. The Kaplan-Meier method was used to assess survivorship (absence of a revision) for primary knee replacement. A proportional-hazards regression model was estimated to assess the role of independent variables on the survival of primary knee replacements. RESULTS: During the period of the study, 7.0 percent (1301) of 18,530 knee replacements were classified as revisions. Significant differences were identified between hospitalizations for primary and revision knee replacements in terms of the patient and hospital characteristics. Patients who were more than fifty-five years old, lived in a rural area, or had a diagnosis of rheumatoid arthritis had a significantly (p < 0.05) longer duration before revision than did other patients. Primary knee replacements performed in a teaching or specialty hospital had a significantly (p < 0.05) shorter duration before revision than did those performed in a non-teaching hospital. The long-term rates of revision were uniformly low. Estimates of the proportion of knee replacements that would need to be revised within seven years ranged from a low of 4.3 percent, with use of the algorithm for the longest time to revision, to a high of 8.0 percent, with use of the algorithm for the shortest time to revision. CONCLUSIONS: Revision of a primary knee replacement was a rare event that depended on a patient's age, gender, and place of residence as well as on the hospital where the primary knee replacement was performed. Estimates of the rates of revision knee replacement after almost seven years ranged from a low of 4.3 percent to a high of 8.0 percent.
9824507 Cross-linking of the CAMPATH-1 antigen (CD52) mediates growth inhibition in human B- and T 1998 Nov The CAMPATH-1H (CD52) antigen is a 21 000-28 000 MW glycopeptide antigen that is highly expressed on T and B lymphocytes and is coupled to the membrane by a glycosylphosphatidylinositol (GPI) anchoring structure. The humanized CAMPATH-1H anti-CD52 antibody is extremely effective at mediating depletion of both normal and tumorigenic lymphocytes in vivo and has been used in clinical trials for lymphoid malignancy and rheumatoid arthritis. Cross-linking GPI-anchored molecules, including CD52, on the surface of T lymphocytes in the presence of phorbol 12-myristate 13-acetate or anti-CD3, results in cellular activation. In the present study we have investigated the functional effects of cross-linking CD52 on T and B tumour cell lines. Cross-linking CD52 on either a B-cell line, Wien 133, which expresses high levels of endogenous CD52 or Jurkat T cells transfected and selected to express high levels of CD52 resulted in growth inhibition. This effect showed slower kinetics and occurred in a lower percentage of cells than growth inhibition stimulated via T- or B-cell receptors. Growth inhibition of the Wien 133 line was followed by the induction of apoptosis, which appeared independent of the Fas/Fas L pathway. Wien 133 cells surviving anti-CD52 treatment were selected and cloned and found to have down-regulated CD52 expression, with a characteristic biphasic pattern of 10% CD52-positive, 90% negative by fluorescence-activated cell sorter analysis. Interestingly, surface expression of other GPI-linked molecules, such as CD59 and CD55, was also down-regulated, but other transmembrane molecules such as surface IgM, CD19, CD20, HLA-DR were unaffected. The present study and previous work show that this is due to a defect in the synthesis of mature GPI precursors. Separation of CD52-positive and negative populations in vitro resulted in a rapid redistribution to the mixed population. Injection of CD52-negative cells into nude mice to form a subcutaneous tumour resulted in a substantial increase in expression of CD52. These results suggest that the defect in the Wien 133 cells is reversible, although the molecular mechanism is not clear. These observations have relevance to the clinical situation as a similar GPI-negative phenotype has been reported to occur in lymphocytes following CAMPATH-1H treatment in vivo.
9158087 Characterization of T cells specific for an epitope of human 60-kD heat shock protein (hsp 1997 May BD is prevalent in the area of the Silk Route. It has been shown that hsp are involved in the T cell activation in patients with BD in the UK, where this disease has developed sporadically. We have thus examined whether the T cell response to the hsp-derived peptides may be induced in patients with BD in Japan, an east pole of the Silk Route. As with patients in the UK, the human 60-kD hsp peptide 336-351 also yielded vigorous proliferation of T cells in Japanese patients with BD, but neither in normal subjects nor in patients with rheumatoid arthritis (RA); there was significant association between proliferation by this peptide and the presence of ocular lesion, but not any other symptoms of BD. To clarify whether the peptide stimulates T cells as a polyclonal activator, a specific antigen or a superantigen-like substance, we analysed T cell receptor (TCR) usage of responding T cells by means of MoAbs specific for TCR Vbeta subfamily and polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP)-based technique. We found that T cells with certain TCR Vbeta subfamilies (including Vbeta5.2-3, 8, 13.6, 18, 21.3) were increased in circulation and responded to the hsp peptide in an antigen-specific fashion. In addition, TCR Vbeta gene-amplified products of freshly isolated T cells of patients with BD formed several bands in the PCR-SSCP analysis; some of them became prominent after stimulation with the peptide. This suggests that T cells in patients with this disease have already been expanded oligoclonally in vivo, which may be a result of stimulation by triggering antigens, including the hsp peptide. In addition, hsp peptide stimulation induced proinflammatory cytokine mRNA expression in peripheral blood mononuclear cells, including IL-8, tumour necrosis factor-alpha (TNF-alpha) and TNF-beta in eight out of eight patients studied. Taken together, the results suggest that hsp antigen may play a role in the pathogenesis of BD, not only in the area of the Silk Route, but also outside the Silk Route area.
9148769 Antibody selection against CD52 produces a paroxysmal nocturnal haemoglobinuria phenotype 1997 Mar 15 The CD52 antigen is a lymphocyte glycoprotein with an extremely short polypeptide backbone and a single N-linked glycan, and it is attached to the cell membrane by a glycosylphosphatidylinositol (GPI) anchor. Treatment of rheumatoid arthritis patients with CAMPATH-1H, a humanized monoclonal antibody against CD52, resulted, in a small number of cases, in the appearance and persistence of CD52-negative T cells. Similarly, CD52-negative B cells emerged following in vitro treatment of a CD52-positive human B cell line with CAMPATH-1H. Both the B and T CD52-negative cells were also found to be defective in surface expression of other GPI-anchored proteins. Biochemical analysis revealed a severe defect in the synthesis of a mature GPI precursor in both the B and T cell lines. Therefore the phenotype of these CD52-negative B and T cells closely resembles that of lymphocytes from patients with paroxysmal nocturnal haemoglobinuria (PNH), in which the first step of the GPI-biosynthetic pathway, i.e. synthesis of GlcNAc-phosphatidylinositol, is blocked. In all cases studied to date, this defect maps to a mutation of the phosphatidylinositolglycan class A (PIG-A) structural gene. We therefore amplified the PIG-A gene from both the GPI-negative B and T cells by PCR and determined the nucleotide sequence. No differences from the wild-type sequence were detected; therefore a classical PNH mutation cannot be responsible for the GPI-biosynthesis defect in these cell lines. Significantly, the GPI-negative phenotype of the B cells was reversible upon separation of the positive and negative cells, resulting in a redistribution to a mixed population with either CD52-positive or -negative cells, whereas populations of 100% CD52-negative T cells were stably maintained during culture. Therefore, whereas the GPI-biosynthesis deficiency in the T cell lines may be due to a mutation in another gene required by the GPI-biosynthetic pathway, the reversible nature of this block in the B cell lines suggests a less direct cause, possibly an alteration in a regulatory factor. Overall, these data demonstrate that the PNH phenotype can be generated without a mutation in the PIG-A structural gene, and thereby identify a novel mechanism for the development of GPI deficiency.
11555411 Associations of MHC class II alleles in Norwegian primary Sjögren's syndrome patients: im 2001 Oct Sjögren's syndrome (SS) is a chronic autoimmune disease characterized by dryness of the eyes and mouth. Currently, the highly polymorphic major histocompatibility complex (MHC) genes are the best documented genetic risk factor for the development of autoimmune disease. We examined the MHC class II alleles DRB1, DRB3, DRB4, DRB5, DQA1 and DQB1 in a group of Norwegian pSS patients and compared with a group of healthy controls. Because a number of studies have shown that some of the MHC class II alleles are not associated with the disease as a whole, but rather to the development of autoantibodies, anti-Ro52 autoantibodies in serum were measured and compared to MHC class II allele status. A clear association with pSS was detected for the DRB1*0301 and DRB3*0101 alleles, but these alleles were more closely associated with the presence of anti-Ro52 autoantibodies than with pSS itself. Moreover, the DQA1*0501 and DQB1*0201 alleles were only associated with the presence of anti-Ro52 autoantibodies. This study shows that the production of anti-Ro52 autoantibodies in pSS is associated with the DRB1*0301, DRB3*0101, DQA1*0501 and DQB1*0201 alleles which are in strong linkage disequilibrium.
9041943 In vitro apoptosis and expression of apoptosis-related molecules in lymphocytes from patie 1997 Feb OBJECTIVE: To analyze factors related to apoptosis in systemic lupus erythematosus (SLE) peripheral blood mononuclear cells (PBMC) and to compare the findings in SLE PBMC with those in normal donor PBMC or PBMC from patients with other autoimmune diseases. METHODS: PBMC from normal healthy donors or patients with SLE, mixed connective tissue disease (MCTD), rheumatoid arthritis (RA), or various vasculitides were isolated. The percentage of apoptosis after activation through different signaling pathways was quantified using propidium iodide staining. Protein expression of Fas/APO-1 or bcl-2, and messenger RNA (mRNA) expression of bcl-2, bcl-xL, bax, bak, Fas/APO-1, Fas ligand (Fas-L), c-myc, mad, or max were determined. RESULTS: We confirmed previous findings of increased numbers of apoptotic cells in SLE PBMC compared with normal donor cells after in vitro incubation. After activation of PBMC with CD28 monoclonal antibody plus phorbol myristate acetate (CD28 MAb/ PMA), staphylococcal enterotoxin B (SEB), or phytohemagglutinin (PHA), the percentage of apoptotic cells was unchanged (SEB) or diminished (CD28 MAb/PMA, PHA) in SLE cells, and the difference between normal donor and SLE cells was less pronounced. On the mRNA level, expression of apoptosis-related gene products did not differ between SLE cells and normal donor cells. Expression of Fas/APO-1 protein was increased in freshly isolated SLE T lymphocytes compared with normal donor T lymphocytes, whereas bcl-2 protein was up-regulated after a 3-day culture period. Cellular activation further increased bcl-2 protein levels, eliminating differences between normal donors and SLE patients. In RA cells, the percentage of apoptosis was similar to that in normal donor PBMC, whereas results using cells from patients with other autoimmune diseases (MCTD, Wegener's granulomatosis, Takayasu arteritis, polyarteritis nodosa) were comparable with those found using SLE PBMC. Addition of growth factors such as interleukin-2 (IL-2), IL-4, or IL-15 to culture medium decreased the percentage of in vitro apoptosis in both normal donor and SLE cells. CONCLUSION: Based on these data, we conclude that accelerated in vitro apoptosis and increased Fas/ APO-1 and bcl-2 protein expression in SLE are nonspecific for the disease, and might be explained at least in part by the increased in vivo activation levels of PBMC from patients with SLE, MCTD, or autoimmune vasculitides combined with in vitro incubation under "noninflammatory" conditions and growth factor withdrawal.
11689139 Rheumatologic manifestations of pediatric HIV infection. 2001 Oct In order to assess the frequency of rheumatologic manifestations at different stages of pediatric human immunodeficiency virus (HIV) infection, 26 HIV-infected children at any stage of infection, seen at the Children's AIDS Clinic of "La Raza" National Medical Center from January 1997 to December 1998, were studied. Rheumatologic manifestations were assessed following the criteria established by the American College of Rheumatology. Blood samples were taken for measuring CD4+ and CD8+ T cells, antinuclear antibodies (ANA), anticardiolipin (ACL) antibodies, and rheumatoid factor (RF). The results were compared to those of 25 HIV-negative children of similar ages. Rheumatologic manifestations were identified in 5 (19.2%) of 26 children. Two of whom were twin sisters with biphasic Raynaud's syndrome, and one had necrosing vasculitis of a finger, as well as lip necrosis and livedo reticularis. These patients were positive for ANA and ACL. One case each of knee arthalgias, vasculitis, and septic arthritis of the ankle were also seen. All of the rheumatologic manifestations were in advanced stages of HIV disease. These rheumatologic changes are similar to those reported for HIV-positive adults, and should be considered as part of the HIV acquired immune deficiency syndrome (AIDS) clinical spectrum in the pediatric population.
10805357 Anti-dsDNA antibodies in sarcoidosis. 2000 Apr BACKGROUND: Sarcoidosis is a chronic multisystem disorder characterized by an exaggerated cellular immune response to antigens with the production of various antibodies including rheumatoid factor and antinuclear antibodies (ANA). The prevalence and significance of antibodies to double-stranded DNA (anti-dsDNA) in sarcoid patients is unknown. The occurrence of anti-dsDNA antibodies is known to be a specific marker of systemic lupus erythematosus (SLE). Sarcoidosis can occur with SLE. It is unclear if anti-dsDNA antibodies in patients with sarcoidosis signify the eventual development of SLE. OBJECTIVES: To determine the prevalence of anti-dsDNA antibodies in patients with sarcoidosis in a university hospital and their significance in predicting the diagnosis of associated SLE. METHODS: In a retrospective study, 34 patient files with diagnosed sarcoidosis in a university hospital during a period of 15 years were reviewed for serological markers, including ANA, anti-dsDNA, and immunoglobulin and C3 levels. The occurrence of SLE in these patients also was evaluated. RESULTS: ANA were positive in 10 of 34 of the patients screened. Two patients with sarcoidosis had antibodies to dsDNA. C3 levels in these 34 patients were an average of 87.7 +/- 25.3 mg/100 mL, which is within the normal range. IgG immunoglobulin levels were an average of 2,206 +/- 999 mg/100 mL, which was above normal limits. The 2 patients who were positive for anti-dsDNA had normal C3 levels and SLE did not develop during a follow-up period of 10 to 15 years. CONCLUSIONS: Anti-dsDNA antibodies may occur in patients with sarcoidosis, but their presence does not predict the subsequent development of SLE.
10616004 Linked production of antibodies to mammalian DNA and to human polyomavirus large T antigen 1999 Dec OBJECTIVE: To test whether the presence of antibodies to human polyomavirus large T antigen, a viral DNA-binding protein essential for productive polyomavirus replication, correlates with the presence of antibodies to single-stranded DNA (ssDNA), double-stranded DNA (dsDNA), or the autologous TATA-binding protein (TBP). METHODS: Sera from patients with various diagnosed or suspected autoimmune syndromes were analyzed for the presence of antibodies to T antigen, DNA, or TATA-binding protein, and correlations were determined. Rheumatoid factor (RF) was studied as a control antibody. RESULTS: A highly significant correlation between antibodies to T antigen and antibodies to ssDNA or TATA-binding protein, but not between anti-T antigen antibodies and RF, was found in all patient groups. Of all sera that were positive for antibodies to dsDNA, 62% were positive for antibodies to T antigen (P<0.03). CONCLUSION: A non-self DNA-binding protein such as human polyomavirus large T antigen may render DNA immunogenic upon binding to nucleosomes when expressed in vivo. This is indicated by the strong correlation between antibodies to T antigen and antibodies to DNA or TBP and is consistent with a hapten-carrier model. This model implies cognate antigen-selective interaction of T antigen-specific T helper cells and DNA-specific B cells or B cells specific for other components of nucleosomes, consistent with the results of previous experiments.
9125246 Soluble oligonucleosomal complexes in synovial fluid from inflamed joints. 1997 Apr OBJECTIVE: To determine whether soluble oligonucleosomal DNA, typical of that released during apoptotic cell death, is present in synovial fluids from inflamed joints and, if so, whether it is present in sufficient concentrations to have pathophysiologic significance. METHODS: Fifty synovial fluid specimens from 46 patients were studied, 41 from joints with a variety of inflammatory disorders and 9 from osteoarthritic joints. DNA from freshly collected synovial fluid was isolated and quantitated by microfluorometry, and the oligonucleosomal fraction was measured by radiolabeling, gel electrophoresis, and autoradiography. Specific immunoprecipitation with monoclonal antihistone antibody, after DNA radiolabeling in whole synovial fluid, was used to detect histone binding. RESULTS: DNA with a typical oligonucleosomal ladder was observed in most specimens. The mean +/- SD oligonucleosomal DNA concentration was 14.1 +/- 18.5 microg/ml in synovial fluids from inflamed joints, considerably higher than that in osteoarthritic synovial fluids. Additionally, the DNA was shown to be complexed with histone, as would be expected. Control experiments were performed to show that the oligonucleosomal DNA was present in soluble form and did not arise due to in vitro artifact. The DNA concentrations were found to correlate significantly with the concentrations of synovial fluid leukocytes, most of which were neutrophils. CONCLUSION: Synovial fluids from inflamed joints contain oligonucleosomal DNA typical of that released during apoptotic cell death. The probable source is fluid-phase neutrophils undergoing apoptotic cell death, although this was not directly demonstrated. The concentrations are sufficient to have biologic activity similar to that shown in vitro, including lymphoproliferation and stimulation of interleukin-6 secretion. A mechanism by which oligonucleosomal DNA may contribute to perpetuation of rheumatoid synovitis is proposed. If it is generalizable to other sites of inflammation, as seems probable, similar oligonucleosomal DNA release accompanying inflammation may play a pathogenetic role in other disorders, including systemic lupus erythematosus.
11752512 Cytokine and immunogenetic profiles in Japanese patients with adult Still's disease. Assoc 2001 Dec OBJECTIVE: To determine cytokines and MHC class II alleles in Japanese patients with adult Still's disease (ASD) and clarify the association between those profiles and chronic articular disease. METHODS: Of 35 patients with ASD (13 men, 22 women, mean age at onset 34.0 yr), 17 (49%) had chronic arthritis (>6 months, chronic articular ASD) and 18 (51%) lacked chronic arthritis (systemic ASD). Cytokines and cytokine receptors in sera were measured by ELISA. Correlations of each cytokine with disease activity or C-reactive protein (CRP) were determined. MHC class II alleles were examined by polymerase chain reaction methods. RESULTS: In chronic articular ASD, female gender was more frequent and liver dysfunction and myalgia were rarer than in systemic ASD. In active disease, the white blood cell count was lower, but total IgG was greater in patients with chronic articular ASD than in those with systemic ASD. Tumour necrosis factor (TNF) alpha, soluble TNF receptor 2 and interleukin (IL)-18 were increased in both types of ASD, even in remission. Soluble IL-2 receptors, IL-4 and IL-18 levels were correlated with disease activity or CRP value only in chronic articular ASD. Interferon gamma and IL-8 remained increased only in chronic articular ASD, even when disease activity, including IL-6 and CRP, was low. DRB1*1501 (DR2) and DRB1*1201 (DR5) alleles were more frequent in chronic articular than in systemic ASD, whereas DQB1*0602 (DQ1) was frequently observed in both types of ASD. CONCLUSION: The present study suggests that ASD with chronic articular disease has distinct clinical, cytokine and immunogenetic profiles.
11409117 Low serum dehydroepiandrosterone sulfate in women with primary Sjögren's syndrome as an i 2001 Jun OBJECTIVE: To assess the hypothalamic-pituitary-adrenal (HPA) and thyroid axes in women with primary Sjögren's syndrome (pSS). METHODS: In 10 women with pSS and 10 age matched female controls, we evaluated serum dehydroepiandrosterone sulfate (DHEA-S), testosterone, androstenedione, follicle stimulating hormone, luteinizing hormone, thyroid stimulating hormone, prolactin, growth hormone, sex hormone binding globulin, cortisol, and adrenocorticotropin hormone (ACTH), in both basal condition and after stimulation with corticotropin releasing hormone, thyrotropin releasing hormone, and luteinizing hormone releasing hormone intravenously. Patients had not previously been treated with glucocorticoids. RESULTS: Patients with pSS had significantly lower basal mean DHEA-S values compared with healthy controls (2.4 +/- 0.4 vs 3.9 +/- 0.3 mumol/l; p < 0.05) and significantly lower DHEA-S values after stimulation. The cortisol/DHEA-S ratio in the patient group was higher than in controls (171 +/- 39 vs 76 +/- 5; p < 0.05). A correlation was found between basal ACTH and DHEA-S values in the patients (r = 0.650; p = 0.05). No correlation was seen between disease activity or age and the serum concentration of DHEA-S. The levels of other hormones both at baseline and after stimulation were similar in patients and controls. CONCLUSION: The results show that women with pSS have intact cortisol synthesis but decreased serum concentrations of DHEA-S and increased cortisol/DHEA-S ratio compared with healthy controls. The findings may reflect a constitutional or disease mediated influence on adrenal steroid synthesis. The thyroid axis and gonadotropin secretion were similar in patients and controls.
11085802 An investigation of interactions between the immune system and stimulus-secretion coupling 2000 Nov OBJECTIVES: To determine whether chronic exposure to lymphocyte-derived cytokines could inhibit the fluid secretory mechanism in salivary gland acinar cells and so account for the loss of gland function seen in the early stages of Sjögren's syndrome. METHODS: Mouse submandibular acinar cells maintained in primary culture were exposed to a profile of cytokines produced by concanavalin A-activated splenic lymphocytes in vitro for periods up to 72 h. Agonist-evoked changes in intracellular Ca(2+) were determined microfluorimetrically in both control and cytokine-treated cells. RESULTS: Acinar cells maintained in primary culture in the presence of cytokines for up to 72 h were able to mobilize intracellular calcium in response to stimulus by acetylcholine in an identical fashion to those maintained in primary culture in the absence of cytokines. Acute application of the conditioned medium produced by the activated lymphocytes had an antisecretory effect on acetylcholine-evoked Ca(2+) mobilization, which was found to be mediated by cholinesterase rather than by cytokines. CONCLUSION: Neither chronic nor acute exposure to the profile of cytokines released by concanavalin A-activated splenic lymphocytes interfered in any way with the second messenger cascade and fluid and electrolyte secretion in acinar cells. Our data suggest an alternative hypothesis, in which elevated levels of cholinesterase can metabolize acetylcholine released within the salivary glands and thus prevent fluid secretion.
9256310 Anti-endothelial cell antibodies in systemic autoimmune diseases: prevalence and clinical 1997 OBJECTIVE: To investigate the prevalence and characteristics of anti-endothelial cell antibodies (AECA) in a large cohort of patients with several well defined systemic autoimmune diseases, in order to determine their relationship with the clinical and laboratory features of these diseases. METHODS: Clinical and laboratory features of 216 consecutive Caucasian patients were prospectively studied. One hundred and seven patients had been diagnosed as having a primary systemic vasculitis-specifically, 39 had temporal arteritis (TA), 25 polyarteritis nodosa (PAN), 9 Wegener's granulomatosis (WG), and 34 Behcet's disease (BD)-, 90 patients had systemic lupus erythematosus (SLE), and 19 had a primary Sjogren's syndrome (SS). The AECA were determined by ELISA. RESULTS: One hundred and four (48%) patients with systemic autoimmune diseases were found to have a positive titre of AECA. Specifically, AECA were detected in 41 (38%) patients with a primary systemic vasculitis (13 (33%) with TA, 14 (56%) with PAN, 5 (56%) with WG and 9 (26%) with BD), in 58 (63%) patients with SLE, and in 5 (26%) patients with a primary SS. In patients with a primary systemic vasculitis, those with AECA were found to have an increased prevalence of disease activity (P < 0.05). In SLE patients, those with AECA were found to have an increased prevalence of vascular lesions (P < 0.05), lupus nephropathy (P < 0.05), and anticardiolipin antibodies (aCL) (P < 0.001). CONCLUSIONS: Patients with systemic autoimmune diseases have a high prevalence of AECA and they are associated with the presence of vascular lesions, nephropathy, and aCL in SLE, as well as with disease activity in several primary systemic vasculitis (TA, PAN, WG and BD).
11285317 Docosahexaenoic acid suppresses function of the CD28 costimulatory membrane receptor in pr 2001 Apr (n-3) polyunsaturated fatty acids (PUFA) have been widely documented to reduce inflammation in diseases such as rheumatoid arthritis. This study sought to elucidate the mechanism whereby (n-3) PUFA downregulate T-cell proliferation. We hypothesized that membrane incorporation of dietary PUFA would alter membrane structure and consequently membrane receptor function. Female C57BL/6 mice were fed for 14 d one of three diets containing arachidonic acid (AA), fish oil or docosahexaenoic acid (DHA) that varied in lipid composition only. Spleens were harvested and T cells ( approximately 90% purity) were activated with agonists that stimulated proliferation at the receptor level [anti-CD3 (alphaCD3)/anti-CD28 (alphaCD28)], intracellularly [phorbol-12-myristate-13-acetate (PMA)/ionomycin] or with a combined receptor/intracellular agonist (alphaCD3/PMA). Although there was no significant difference (P > 0.05) in proliferative response across dietary groups within each agonist set, interleukin (IL)-2 secretion was significantly reduced (P = 0.05) in cells from DHA-fed mice stimulated with alphaCD3/alphaCD28. In parallel in vitro experiments, Jurkat T cells were incubated with 50 micromol/L linoleic acid, AA, or DHA. Similar agonists sets were employed, and cells incubated with DHA and AA had a significantly reduced (P < 0.05) IL-2 secretion in three of the agonist sets. However, only when the CD28 receptor was stimulated was there a significant difference (P < 0.05) between DHA and AA. The results of this study suggest the involvement of the CD28 receptor in reducing IL-2 secretion in DHA-fed mice and DHA-incubated Jurkat cells and that purified T cells from DHA-fed mice require accessory cells to modulate proliferative suppression.
10870096 Additive effect of indomethacin and methotrexate on suppression of growth in rats. 1999 Nov The purpose of this study was to investigate the medium-term effects of methotrexate (MTX) and indomethacin on the growth of young rats. Four equal groups of Sprague-Dawley male rats (four animals in each group; mean+/-S.D. body weight, 183+/-13 g, in their rapid growth phase) were subjected to the following drug treatment: one group was given MTX (0.2 mg kg(-1) body weight) subcutaneously on every fourth day, another received indomethacin (2.5 mg kg(-1) body weight) subcutaneously daily and the third group was given both of these drugs (MTX on every fourth day and indomethacin daily). The fourth group was injected subcutaneously with physiological saline every day to serve as a control group. Total body weight, food and water consumption by animals in each group were monitored every second day for a period of 10 weeks. After this period, liver, spleen and kidneys were excised, weighed and analysed for MTX and dihydrofolate reductase activity. Compared with the groups, which received MTX alone, indomethacin alone, or physiological saline, mean increase (17+/-11 g) in body weight of rats was minimal in the group receiving both MTX and indomethacin. The difference was statistically significant (p=0.001) when the values of mean increase in body weight of rats in different treatment groups after a 10-week treatment were compared. The mean weights of liver and spleen in this group receiving both MTX and indomethacin were also found to be significantly less than the weights of these organs in the control group (p<0.01). There also appears to be a decline in food consumption in this group (p<0.05). This negative effect on growth of animals in this group appears to be not only due to decreased food consumption but also due to increased inhibition of de novo pathway of DNA synthesis. This is supported by increased accumulation of MTX and decreased dihydrofolate reductase activity in this group receiving both MTX and indomethacin, as compared with the group receiving MTX alone. The data indicate an additive effect of MTX and indomethacin on the suppression of growth in young rats, alluding to the notion that patients suffering from juvenile rheumatoid arthritis or acute lymphoblastic leukaemia receiving these two drugs concomitantly over a long period of time might be at a risk of experiencing short-term suppression of growth.
9587393 Bone marrow transplantation for autoimmune diseases. 1998 Bone marrow transplantation (BMT) is now becoming a powerful strategy for the treatment of patients with autoimmune diseases. Using various animal models for autoimmune diseases, we have previously found that allogeneic BMT (not autologous BMT) can be used to treat autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), immune thrombocytic purpura, insulin-dependent diabetes mellitus (IDDM), chronic glomerulonephritis, and certain types of non-insulin-dependent diabetes mellitus. In contrast, we have found that the transplantation of T-cell-depleted bone marrow cells or partially purified hemopoietic stem cells (HSCs) from autoimmune-prone mice to normal mice leads to the induction of autoimmune diseases in the recipients. These findings have recently been confirmed even in humans; autoimmune diseases such as RA, SLE, multiple sclerosis, and Crohn's disease were resolved after allogeneic BMT. However, there have recently been reports on the rapid recurrence or persistence of autoimmune diseases after autologous BMT. Conversely, the adoptive transfer of autoimmune diseases such as myasthenia gravis, IDDM and Graves' disease by allogeneic BMT from donors to recipients has been reported. Based on these findings, we have proposed that autoimmune disease is 'a stem cell disorder'. To clarify the differences between normal and abnormal HSCs, we have established a new method for purifying HSCs. Using this method, we purified HSCs from normal and autoimmune-prone mice and compared the former with the latter. We have found that a major histocompatibility complex (MHC) restriction exists between normal HSCs and stromal cells, whereas there is no MHC restriction between abnormal HSCs and stromal cells either in vivo or in vitro; abnormal HSCs proliferate even in allogeneic environments. Abnormal HSCs thus appear to be more resilient than normal HSCs. In humans, BMT across MHC barriers has had a low success rate as a consequence of (1) graft-versus-host disease (GVHD), (2) graft rejection and (3) incomplete recovery of T cell functions. However, we have found that such problems can be overcome in mice. GVHD can be prevented if T-cell-depleted bone marrow cells are used. Graft rejection can be prevented by bone grafts to recruit donor stromal cells, since, as we have found, an MHC restriction exists between HSCs and stromal cells. In addition, we have found that stromal cells migrate from the bone marrow to the thymus, where they become engaged in positive selection. Therefore, the bone grafting to recruit donor stromal cells leads to a complete recovery of T cell functions, since T cells, which are positively selected by donor stromal cells in the thymus, can cooperate with donor B cells and antigen-presenting cells. In humans, it is well known that the success rate of BMT in patients more than 45 years old is low. Recently, we have found that the low success rate is due to the aging of the thymus, and that BMT plus embryonal thymus grafts can be used to treat late-onset autoimmune diseases in MRL/+ mice. Based on these findings, we would like to suggest that the transplantation of the embryonal thymus in conjunction with BMT will become a valuable strategy for treating older patients with various intractable diseases, including autoimmune diseases. We believe that similar conditions (to permit successful allogeneic BMT) to those in mice will be realized in humans in the near future.