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ID PMID Title PublicationDate abstract
1522214 Purification and partial sequencing of the nuclear autoantigen RA33 shows that it is indis 1992 Sep RA33 is a nuclear autoantigen with an apparent molecular mass of 33 kD. Autoantibodies against RA33 are found in about 30% of sera from RA patients, but only occasionally in sera from patients with other connective tissue diseases. To characterize RA33, the antigen was purified from HeLa cell nuclear extracts to more than 90% homogeneity by affinity chromatography on heparin-Sepharose and by chromatofocusing. Sequence analysis of five tryptic peptides revealed that their sequences matched corresponding sequences of the A2 protein of the heterogeneous nuclear ribonucleoprotein (hnRNP) complex. Furthermore, RA33 was shown to be present in the 40S hnRNP complex and to behave indistinguishably from A2 in binding to single stranded DNA. In summary, these data strongly indicate that RA33 and A2 are the same protein, and thus identify on a molecular level a new autoantigen.
1385104 Prorenin-renin axis in synovial fluid in patients with rheumatoid arthritis and osteoarthr 1992 Jun This study was undertaken 1) to determine whether or not renin is present in synovial fluid in patients with rheumatoid arthritis and osteoarthritis, and, if present, 2) to investigate whether it is synthesized in synovial fluid, or it is only transported from the circulation into the synovial cavity. The active renin concentration (indirect) was measured with angiotensin I radioimmunoassay kits. Inactive renin was converted into active renin with Sepharose-bound trypsin. Both active and inactive forms of renin were found in synovial fluid. They were significantly higher in patients with rheumatoid arthritis (n = 9) than in those with osteoarthritis (n = 16). In plasma, the concentration of inactive renin was significantly higher (P less than 0.001) in the former. Albumin, transferrin, alpha 2-macroglobulin, ceruloplasmin and immunoglobulins G and M were also found in synovial fluid. In each disease, a plot of the log ratio of synovial fluid to the serum concentration against the log molecular weight of each protein gave an approximately straight line curve, suggesting that these proteins are derived from the circulation and are transported into the synovial cavity. In contrast, the ratio of synovial fluid to plasma concentrations of active renin was significantly higher than that predicted on the basis of the above-mentioned interrelationships in both diseases, whereas the ratio of inactive renin was significantly lower. These findings suggest that 1) inactive and active renin are filtered into the synovial fluid from the circulation, and that 2) inactive renin is converted into the active form in the fluid.
7880194 Selective induction of IgM rheumatoid factors by CD14+ monocyte-lineage cells generated fr 1995 Mar OBJECTIVE: To determine the capacity of CD14+ monocyte-lineage cells induced from bone marrow of rheumatoid arthritis (RA) patients to stimulate the production of IgM rheumatoid factor (IgM-RF), in order to explore the functional abnormalities of CD14+ cells and gain insight into the mechanism of selective synthesis of IgM-RF in RA. METHODS: CD14+ cells were induced by granulocyte-macrophage colony-stimulating factor (GM-CSF) stimulation of CD14- cells purified from bone marrow cells obtained from 6 RA patients and 6 osteoarthritis (OA) patients. The production of IgM and IgM-RF was induced by stimulating B cells from normal healthy individuals with immobilized anti-CD3-activated autologous CD4+ T cells. The effects of CD14+ cells on the proportion of IgM-RF to total IgM produced by the normal B cells were assessed. RESULTS: CD14+ cells induced by GM-CSF stimulation of bone marrow CD14- cells from the 6 RA patients significantly enhanced the proportion of IgM-RF to total IgM produced by anti-CD3-activated CD4+ T cell-stimulated normal B cells (P < 0.05), whereas GM-CSF-induced CD14+ cells from the bone marrow of the 6 OA patients did not significantly affect IgM-RF production. CD14+ cells induced by GM-CSF obtained from different sites in the same RA patient on different occasions consistently enhanced the proportion of IgM-RF to IgM produced by B cells from different normal subjects. CONCLUSION: These results indicate that abnormal CD14+ monocytes stimulate RF-producing B cells to be ready to be activated by the signals delivered through noncognate T-B interactions with anti-CD3-activated T helper cells. Moreover, the data suggest that the accelerated generation of such functionally abnormal CD14+ cells from bone marrow precursors might play an important role in the pathogenesis of RA.
8702434 The CD69 activation pathway in rheumatoid arthritis synovial fluid T cells. 1996 Aug OBJECTIVE: To study the CD69 activation pathway in synovial fluid (SF) T lymphocytes from patients with rheumatoid arthritis (RA). METHODS: Peripheral blood mononuclear cells (PBMC) or SF mononuclear cells (SFMC) were used in proliferation assays with anti-CD69, anti-CD28, anti-CD3, phorbol myristate acetate (PMA), and/or recombinant interleukin-2 (IL-2). CD69+, CD69-, and resting SF T cells were also proliferated. CD25 expression and production of IL-2 after CD69 activation were assessed by flow cytometry and in a bioassay with the IL-2-dependent cell line CTLL-2. RESULTS: RA SFMC did not proliferate either in the presence of anti-CD69 monoclonal antibodies alone or with concomitant PMA activation, when compared with paired or control PBMC. Similar low proliferative responses via the CD3 or CD28 pathway with PMA were observed. This defective proliferation of RA SFMC after stimulation through the CD69 molecule was explained in part by a failure to express CD25 and to produce IL-2. SF CD69- T cells and resting SF T cells had higher rates of proliferation through the alternative costimulatory pathway CD28 than did SF CD69+ T cells or freshly isolated SF T cells. CONCLUSION: Freshly isolated SF T cells present a profound state of hyporesponsiveness through the CD69 and CD28 costimulatory pathways. This state appears to be dependent on the activation status of SF T cells, since CD69- and resting SF T cells showed recovery of the ability to proliferate through the CD28 activation pathway.
8182641 Prevalence of rheumatic diseases in Taiwan: a population study of urban, suburban, rural d 1994 Feb OBJECTIVE: To determine the prevalence of symptomatic rheumatic disease in rural, urban and suburban areas of Taiwan by a 2-staged population survey. METHODS: Nine thousand subjects over 20 years old were sampled proportional to age and sex for the area from 3 administrative areas in Taiwan. A pretested questionnaire to screen for potential rheumatic disorders and/or disability was administered in the communities by health workers. Subjects who screened positive were examined by a rheumatologist who assigned a final diagnosis based on established criteria. RESULTS: A total of 8998 persons over age 20 residing in Hen-San (rural area), Sien-Dien (suburban), and Cu-Tien (urban) were studied. Twenty-five percent (2272) of the population indicated rheumatic problems: 1124 of 2271 were evaluated by a rheumatologist with serological and radiological testing. The response rates were 49.7% in Hen-San, 50.7% in Sien-Dien and 48.5% on Cu-Tien. After age and sex adjustment, the prevalence of rheumatic symptoms in Hen-San, Sien-Dien, and Cu-Tien was 24.3, 18.4 and 26.3% respectively. It was significantly higher in rural Hen-San and urban Cu-Tien than in Sien-Dien. The prevalence of rheumatoid arthritis (RA) in Hen-San, Sien-Dien, and Cu-Tien was 0.26, 0.78, and 0.93%, osteoarthritis (OA) was 6.3, 5.8, 5.1%, ankylosing spondylitis (AS) was 0.54, 0.19, 0.4%, gout was 0.16, 0.67, 0.67%, respectively. The prevalence of RA in Sien-Dien and Cu-Tien was significantly higher than in Hen-San (p < 0.05) but were not statistically different for OA, AS and gout among those 3 sites. Only one case of systemic lupus erythematosus (SLE) was found in urban Cu-Tien for a prevalence of 0.033%. CONCLUSION: Our results suggest that the prevalence of RA and AS is similar to that reported in Caucasians. We could not confirm anecdotal reports that SLE was common or that it is more common than RA in people of Chinese ancestry. The prevalence of OA of the hip is comparatively uncommon in our population. The difference in prevalence of rheumatism, RA, OA and gout in these areas suggests areas of further study.
1370300 The susceptibility sequence to rheumatoid arthritis is a cross-reactive B cell epitope sha 1992 Jan Immunological responses to bacterial heat shock proteins have been implicated in the pathogenesis of arthritis in animals and humans. The predicted amino acid sequence of dnaJ, a heat shock protein from Escherichia coli, contains an 11-amino acid segment that is homologous to the third hypervariable region of the human histocompatibility antigen (HLA) DRB10401 (formerly known as HLA Dw4), the part of the molecule that carries susceptibility to rheumatoid arthritis. To test the biological significance of this finding, we expressed and purified recombinant dnaJ (rdnaJ), and determined its immunologic cross-reactivity with HLA DRB10401. A rabbit antipeptide antiserum raised against the sequence of the third hypervariable region of HLA DRB10401 specifically bound to 'dnaJ, thus confirming that a similar sequence is expressed on the bacterial protein. Of greater consequence, an antiserum to the 'dnaJ protein recognized not only a peptide from the third hypervariable region of HLA DRB10401, but also the intact HLA DRB10401 polypeptide. Furthermore, the antibody to 'dnaJ reacted with HLA DRB10401 homozygous B lymphoblasts, but not with HLA DRB11501, DRB10101, DRB10301, and DRB10701 (formerly known as HLA Dw2, DR 1, DR 3, and DR 7, in the same order) homozygous cells. These results demonstrate that exposure to a bacterial heat shock protein can elicit antibodies against the rheumatoid arthritis susceptibility sequence in the third hypervariable region of HLA DRB10401.
1334644 Bone resorption by cells isolated from rheumatoid synovium. 1992 Nov Cellular mechanisms accounting for the osteolysis of rheumatoid erosions are poorly understood. Cells were isolated and characterised from the synovium of 16 patients with rheumatoid arthritis (RA) and four patients with osteoarthritis and their ability to resorb bone was assessed using a scanning electron microscope bone resorption assay. Macrophages were the major cell type isolated from the synovium of patients with RA. These produced extensive roughening of the bone surface without resorption pit formation. This low grade type of bone resorption was not affected by systemic (calcitonin, parathyroid hormone, 1,25-dihydroxyvitamin D3) or local (interleukin 1, prostaglandin E2) factors influencing bone resorption. Macrophage mediated bone resorption differs qualitatively and quantitatively from that of osteoclasts but is likely to play an important part in the development of marginal erosions in RA.
1613741 Nonsteroidal antiinflammatory drugs: benefit/risk evaluation in rheumatic diseases. 1992 Jan Side effects of nonsteroidal antiinflammatory drug (NSAID) therapy are attributed to direct damage by the acidic compounds and to the secondary effects of prostaglandin inhibition. In general, gastrointestinal, skin and central nervous system effects predominate, followed by general adverse hepatic and renal events. Advanced age, female gender, history of gastrointestinal disorders and renal impairment increase the risk of NSAID induced side effects. Pharmacologic modifications that may help minimize side effects include lowered cyclooxygenase inhibitor activity, more stable plasma/tissue concentrations, decreased lipophilicity, avoidance of biliary excretion and renal excretion in inactive form. Prescribing NSAID according to their differing pharmacokinetic profiles may help maximize clinical efficacy and reduce side effects.
8894357 The effect of ranitidine on NSAID related dyspeptic symptoms with and without peptic ulcer 1996 Sep The efficacy of ranitidine in the treatment of NSAID-related dyspeptic symptoms with and without peptic ulcer disease (PUD) was investigated in 124 patients with rheumatoid arthritis (RA) and osteoarthritis (OA). The patients, who continued the use of NSAIDs were investigated by gastroduodenoscopy. Patients with PUD received open label ranitidine 150 mg b.i.d. and the patients without PUD were randomly allocated to receive ranitidine 150 mg b.i.d. or placebo for 4 weeks. PUD was found in 36 (26%) consecutive patients who presented with dyspeptic symptoms. Of these patients dyspeptic symptoms had disappeared in 8 (26%) of 31 evaluable patients and PUD was healed in 18 (56%) patients after 4 weeks of treatment. After 8 weeks of treatment PUD was healed in 27 (87%) patients. Of the remaining patients without PUD dyspeptic symptoms had disappeared in 24 (26%) of the ranitidine-treated patients which was significantly better (p < 0.02) than the 5 (6%) placebo-treated patients. The minor mucosal lesions found in this patient group improved to a similar extent in the ranitidine and placebo-treated patients although 1 placebo-treated patient deteriorated and 2 placebo-treated patients developed PUD during the 4 weeks of study. The results of this study show that oral ranitidine 150 mg b.i.d. is effective in the treatment of both dyspeptic symptoms and mucosal lesions in RA and OA patient who continue the use of NSAIDs.
1737625 Localized deposition of amyloid in articular cartilage. 1992 Jan The frequency, nature and tissue distribution of localized amyloid deposits in articular cartilage of young and elderly patients, with and without evidence of arthritic disease, was determined. Localized amyloid deposits in articular cartilage were not found in young patients with osteoarthritis of the hip or chondromalacia/osteoarthritis of the patella. However, in elderly patients with osteoarthritis of the hip, amyloid deposits were commonly found, although at no greater frequency than in elderly patients with no evidence of arthritis. Amyloid deposits were commonly present (in 95% of cases) in osteoarthritis of the knee joint and in the articular cartilage of all joints containing pyrophosphate deposits. Similar deposits of amyloid were also found in the articular cartilage of 40-45% of rheumatoid joints. These findings indicate that localized amyloid deposits in the articular cartilage are largely age-related and not due to specific pathological alterations affecting articular cartilage.
8982138 Increased degradation and altered tissue distribution of cartilage oligomeric matrix prote 1996 Nov We investigated the degradation and tissue distribution of cartilage oligomeric matrix protein in normal, osteoarthritic, and rheumatoid arthritic articular cartilage of the human knee. Cartilage was subjected to sequential extractions with buffers containing neutral salt, with EDTA, and finally with guanidine/HCl and then was analyzed by Western blotting with a polyclonal antiserum to human cartilage oligomeric matrix protein. Western blots of the nine neutral salt extracts from normal cartilage revealed mostly intact pentameric molecules of cartilage oligomeric matrix protein, in contrast to the 13 osteoarthritic and five rheumatoid arthritic cartilage samples that demonstrated marked degradation of cartilage oligomeric matrix protein as noted by a predominance of reduction-sensitive bands at approximately 150 kDa and nonreduction-sensitive bands in the 67-94 kDa range. The EDTA and guanidine/HCl extracts from all groups were similar and showed mostly intact molecules of cartilage oligomeric matrix protein, with smaller amounts of degraded cartilage oligomeric matrix protein identical to those resolved by the Western blots of the neutral salt extracts. Western blots of matched pairs of synovial fluid and cartilage extracts demonstrated cartilage oligomeric matrix protein fragments of the same molecular mass. Competitive enzyme-linked immunosorbent assay revealed significantly less cartilage oligomeric matrix protein in rheumatoid articular cartilage than in either normal or osteoarthritic cartilage. In contrast to normal cartilage, where cartilage oligomeric matrix protein was predominantly localized to the interterritorial matrix throughout all zones of the matrix, with increased staining in the deeper cartilaginous zones, the most intense staining in osteoarthritic cartilage was in the superficial zones of fibrillated cartilage, with little to no immunostaining in the midzones and relatively poor staining in the deeper cartilaginous zones. This distribution was the inverse of that for proteoglycans, as demonstrated by toluidine blue staining, where proteoglycans were depleted primarily from the superficial fibrillated cartilage. In mild to moderately affected rheumatoid cartilage, the tissue distribution of cartilage oligomeric matrix protein was similar to the distribution of proteoglycans, with relatively uniform staining of the interterritorial and territorial matrics. In more severely affected rheumatoid cartilage, the superficial zones demonstrated punctate immunostaining for cartilage oligomeric matrix protein in the interterritorial and territorial matrics, and staining was restricted to the territorial matrix in the deep cartilaginous zones. It is evident from this study that (a) noncollagenous proteins such as cartilage oligomeric matrix protein are greatly affected in arthritis, (b) degradation fragments released from the matrix into the synovial fluid reflect the processes occurring within the matrix, and (c) different zones of the articular cartilage are susceptible to degradation of cartilage oligomeric matrix protein in the different disease processes.
7518520 Soluble E-selectin is increased in inflammatory synovial fluid. 1994 Apr OBJECTIVE: To investigate the hypothesis that soluble E-selectin (sE-selectin) may be detected in synovial fluid (SF) and play a role in inflammatory arthritis. METHODS: We used a sandwich ELISA to measure sE-selectin in the SF of 58 patients with rheumatoid arthritis (RA), 9 with psoriatic arthritis (PsA), 30 with osteoarthritis (OA), 13 with gout, and 9 with calcium pyrophosphate dihydrate crystal deposition disease (CPPD). RESULTS: SF sE-selectin values in RA (mean 1.49 ng/ml, 0.18-3.90) and PsA (mean 1.36 ng/ml, 0.88-2.31) were significantly higher than those with OA (mean 0.83 ng/ml, 0.00-1.83), gout (mean 1.04 ng/ml, 0.11-3.42), or CPPD (mean 0.80 ng/ml, 0.20-1.47). Elevated SF sE-selectin was associated with elevated serum sE-selectin, erythrocyte sedimentation rate, and SF white blood cell count. CONCLUSION: Our findings suggest that endothelial cell activation and E-selectin may contribute to the development of inflammatory processes.
8356997 Safety experience with nabumetone versus diclofenac, naproxen, ibuprofen, and piroxicam in 1993 Aug 9 The comparative safety of nabumetone (1,000-2,000 mg/day) versus diclofenac (100-200 mg/day), naproxen (500-1,500 mg/day), piroxicam (10-20 mg/day), and ibuprofen (1,200-3,200 mg/day) was evaluated in a 12-week, randomized, open-label, multicenter study. Patients with osteoarthritis (OA) or rheumatoid arthritis (RA) were enrolled in a 3:1 ratio (nabumetone:one of the four comparator NSAIDs). The incidence of > or = 1 adverse event considered by the investigator to be related or probably related to therapy was similar in all groups. However, significantly (p < 0.02) more diclofenac-treated patients experienced abdominal pain and/or gastritis than nabumetone-treated patients. Naproxen-treated patients experienced significantly (p < 0.002) more dyspepsia as compared with patients treated with nabumetone or ibuprofen and significantly (p < or = 0.001) more nabumetone-treated patients experienced diarrhea than patients treated with naproxen, ibuprofen, or piroxicam. Ulcers occurred in one (0.03%) nabumetone-treated patient versus six (0.5%) patients treated with one of the comparator NSAIDs (p = 0.001). A decrease in hemoglobin > or = 1.5 g/dL occurred in fewer nabumetone-treated patients than in patients treated with diclofenac (p < 0.04), ibuprofen (p < or = 0.04), or piroxicam (p = 0.055). Finally, a similar percentage of patients in all treatment groups withdrew from the study because of adverse events related or probably related to treatment. More (p < 0.001) diclofenac-treated patients withdrew because of elevated hepatic transaminases than patients treated with the other agents. Withdrawal because of gastritis was also noted for more diclofenac-treated patients than nabumetone-treated patients (p < 0.04). In conclusion, nabumetone was demonstrated to be at least as safe as diclofenac, piroxicam, ibuprofen, and naproxen as related to subjective complaints, such as dyspepsia or gastritis. However, more serious events, such as ulcers or meaningful decreases in hemoglobin, seem to occur less often with nabumetone.
8730110 Cloning of collagenase 3 from the synovial membrane and its expression in rheumatoid arthr 1996 Apr OBJECTIVE: To analyze synovial membrane of patients with rheumatoid arthritis (RA) for the expression of unknown matrix metalloproteinases (MMP). METHODS: Degenerate oligonucleotides corresponding to highly conserved regions of the MMP gene family and the rapid amplification of cDNA ends (RACE) method have been used to search for new members of this gene family. MMP gene expression has been characterized by Northern blot analysis. RESULTS: We cloned a MMP cDNA from the synovial membrane that is completely identical to the recently published collagenase 3 cDNA derived from a human breast cancer cDNA library (Freije, et al: J Biol Chem 1994;269:16766-73). Collagenase 3 is expressed in parallel with interstitial collagenase and stromelysin 1 in RA and osteoarthritis (OA). Collagenase 3 gene expression was not detected in several normal human tissues. CONCLUSION: The expression of collagenase 3 in the synovial membrane in RA and OA suggests its involvement in articular tissue degradation.
8445045 Cytokine profile in systemic lupus erythematosus, rheumatoid arthritis, and other rheumati 1993 Jan We investigated serum levels of interleukin-6 (IL-6), interferon-gamma (IFN-gamma), and tumor necrosis factor alpha (TNF alpha) from patients with systemic lupus erythematosus (SLE) and its various clinical manifestations of disease and from patients with rheumatoid arthritis (RA) and other rheumatic diseases. The serum levels of IL-6 and IFN-gamma were highly elevated from patients with SLE associated with lymphadenopathy (LN) or nephrotic syndrome (NS). On the contrary, the serum levels of TNF alpha were elevated from most patients with SLE associated with thrombocytopenia (TP). However, serum levels of TNF alpha were in the normal range from patients with SLE associated with NS, LN, or central nervous system disease. Of interest, patients with SLE associated with humoral immunodeficiency disorder, hypogammaglobulinemia, had highly elevated levels of serum IL-6. The concanavalin A-stimulated mononuclear cells (MNC) of patients with SLE associated with TP secreted highly elevated levels of TNF alpha compared to other patient groups. We suggest that abnormal production of various cytokines in SLE is an intrinsic defect of MNC and the immune system that may be the key element for a variety of clinical manifestations of this disease.
1606729 Interferon-alpha and dexamethasone inhibit adhesion of T cells to endothelial cells and sy 1992 Jun We investigated whether interferon-gamma (IFN-gamma), interferon-alpha (IFN-alpha) and glucocorticoids affected the adhesion of T cells to human umbilical endothelial cells or human synovial cells. About 30% of peripheral blood T cells could bind to unstimulated endothelial cells, but only a few T cells could bind to unstimulated synovial cells. When both endothelial cells and synovial cells were cultured with recombinant IFN-gamma (rIFN-gamma), the percentage of T cell binding to both types of cells increased in a dose-dependent manner. rIFN-alpha and dexamethasone blocked the T cell binding to unstimulated endothelial cells. Furthermore, rIFN-alpha and dexamethasone suppressed T cell binding to both endothelial cells and synovial cells stimulated by IFN-gamma, and also inhibited intercellular adhesion molecule-1 (ICAM-1) expression on both endothelial cells and synovial cells stimulated by IFN-gamma. These results suggest that IFN-alpha and glucocorticoids may inhibit T cell binding to endothelial cells or synovial cells by modulating adhesion molecule expression on these cells.
8457224 Levels of circulating tumor necrosis factor alpha and interleukin-6 in patients with rheum 1993 Apr OBJECTIVE: To measure serum levels of tumor necrosis factor alpha (TNF alpha) and interleukin-6 (IL-6) in patients with rheumatoid arthritis (RA) and age-matched control subjects and to study how these correlate with serum levels of hyaluronan (HA) and antigenic keratan sulfate (KS) and other biochemical as well as clinical indicators of disease activity. METHODS: Immunoassays were used to measure levels of TNF alpha, IL-6, HA, and antigenic KS in the serum of 35 patients with RA and a group of age- and sex-matched control subjects. Clinical disease activity in the RA group was assessed using the Lansbury index. Drug intake was recorded and the erythrocyte sedimentation rate, and levels of fibrinogen, creatinine, bilirubin, alkaline phosphatase, lactate dehydrogenase, and aminotransferase were measured. RESULTS: Serum levels of TNF alpha, IL-6, and HA were significantly higher in the RA population than in the control group. In patients with RA, serum levels of HA correlated positively with serum levels of TNF alpha and with clinical joint scores, but only weakly with other laboratory parameters of inflammation. Serum levels of antigenic KS correlated negatively with levels of circulating TNF alpha, but much more weakly with other clinical and biochemical parameters of disease activity. CONCLUSION: These in vivo data support in vitro studies which have shown that TNF alpha is a potent stimulator of HA synthesis by synovial lining cells. The results strengthen the contention that serum HA may be a unique marker of synovial involvement and inflammation, rather than of only inflammation, in RA.
7561187 Elevated levels of iC3b and C4d, but not Bb, complement fragments from plasma of persons i 1995 Oct Plasma levels of complement (C) fragments iC3b, C4d, and Bb from human T cell leukemia virus (HTLV)-positive subjects with HTLV-I-associated myelopathy (HAM)/tropical spastic paraparesis (TSP) were analyzed by EIA. Both iC3b and C4d levels were significantly elevated in persons with HAM/TSP. These levels were similar to those in patients with human immunodeficiency virus (HIV) infection or rheumatoid arthritis (RA), who are known to have increased C fragments. Bb levels in persons with HAM/TSP wer unaffected, suggesting that C activation occurred only via the classical pathway. This differed from findings in HIV-infected or RA patients, who had elevated levels of Bb. The results showed an increase in C activation in persons with HAM/TSP and activation via the classical pathway, likely mediated by virus or immune complexes. It is possible that the C activation observed in these subjects contributed to the inflammatory pathogenesis of HAM/TSP.
8776794 Ambulatory polysomnography using a new programmable amplifier system with on-line digitiza 1996 May A new system for polysomnographic recording at home is presented. It consists of a 12 to 24-channel amplifier system with direct digitization of the polygraph signals using a portable computer. Sampling frequency, amplification and filter settings can be defined by the user, and the signals are evaluated at bedside. Technical testing proved a high signal/noise ratio, linear amplification and a good signal quality. Clinical testing of the first 100 recordings showed that they were acceptable for conventional sleep scoring in 98 cases. A comparison of two consecutive recordings was done in 9 healthy subjects and 11 patients with rheumatic disorders. Using conventional sleep staging, only a slight "first night effect" (FNE) was demonstrated in the sleep architecture. Power spectral analysis using autoregressive modeling demonstrated only a difference of power between the 2 nights in the beta (14.5-25 Hz) band. In conclusion, the usability and technical advantages make the system very suitable for ambulatory recordings and only a minimal FNE should be considered when results are evaluated.
8440074 Subclasses of immunoglobulins and autoantibodies in autoimmune diseases. 1993 Jan The differing capacity of subclasses of IgG to bind to protein A and protein G was used in a sequential affinity purification procedure to examine immunoglobulin isotypes and subclasses in autoimmune disease. The utility of the procedure is that affinity-purified fractions containing particular isotypes and subclasses of immunoglobulin can be analyzed for their content of autoantibodies using standard techniques. For each of four autoimmune diseases studied, chronic active hepatitis, Sjogren's syndrome, primary biliary cirrhosis, and rheumatoid arthritis, there were characteristic protein elution profiles and the various disease-specific autoantibodies showed preferential distributions among the isotypes and subclasses. Moreover there was not an absolute correlation between an increased level of a particular subclass and the occurrence of antibodies of that subclass. The occurrence of highly disease-specific immunoglobulin subclass profiles suggests that the hypergammaglobulinemia associated with autoimmunity cannot be attributed entirely to polyclonal B-cell activation. Rather, there are disease-specific alterations in isotype subclass switching which may reflect different cytokine-dependent influences on autoimmune B cells and their products.