bluuebunny/crossref_metadata_2025_split huggingface dataset:
In Vivo and in Vitro Stimulation of Chondrocyte Biosynthetic Activity in Early Experimental Osteoarthritis
Authors: Sandy John D. , Adams Mark E. , Billingham Michael E. J. , Plaas Anna , Muir Helen 
Published: February 2007

AbstractThe biosynthesis of proteoglycans in the menisci and articular cartilages of the knee (stifle) of mature beagles was studied in the early stages of experimental osteoarthritis. The rate of proteoglycan synthesis, determined by systemic labeling in vivo at 21, 42, and 84 days after sectioning of the anterior cruciate ligament, was generally found to be 1.5—2.5‐fold higher than control in articular cartilages and 3—10‐fold higher than control in menisci. The medial meniscus was more stimulated than the lateral meniscus, and the medial tibial plateau under the meniscus was more stimulated than the adjacent tibial area. This area‐specific stimulation suggests the involvement of mechanical factors in the cellular response. The rate of proteoglycan synthesis determined in vitro at 7, 14, and 21 days after operation was also about 2‐fold higher than control in articular cartilages and about 3‐fold higher in menisci. This increase in biosynthetic activity in vitro was confirmed by 35S‐autoradiography and appeared to be due to general stimulation of existing chondrocytes, particularly in the middle and deep zones of the articular cartilage and throughout the meniscal cartilage. The rate of proteoglycan synthesis determined in vitro in cartilages from 2‐week and 3‐week sham operated joints was also increased relative to controls, suggesting that humoral as well as mechanical factors are involved in stimulating chondrocyte activity.
Cartilage Nucleoside Triphosphate (NTP) Pyrophosphohydrolase
Authors: Ryan Lawrence M. , Wortmann Robert L. , Karas Barbara , Mccarty Daniel J. 
Published: February 2007

AbstractWhen 1 mM ATP was added to ambient media of canine cartilage in organ culture or canine chondrocytes in monolayer culture, PPi was generated linearly over 4 hours. The appearance of PPi was related to an ecto‐enzyme based upon its ability to act upon extracellular substrate, to generate extracellular products, failure to detect enzyme activity in supernatant media, failure to increase activity by cell disruption, and susceptibility to digestion by extracellular trypsin. The enzyme responsible for PPi generation is nucleoside triphosphate (NTP) pyrophosphohydrolase, which acts upon a number of purine and pyrimidine nucleoside triphosphates. This enzyme may play a role in generation of extracellular PPi which participates in calcium pyrophosphate dihydrate crystal formation.
HLA—‐DR4 is not a requisite for autoimmunity to collagen in rheumatoid arthritis
Authors: Kammer Gary M. , Trentham David E. 
Published: February 2007

AbstractImmunogenetic studies in rheumatoid arthritis have demonstrated an increased frequency of the HLA—‐DR4 alloantigen in individuals with both the sporadic and familial forms of the disease. To investigate the significance of this association, we ascertained whether the possession of DR4 is necessary for the expression of cellular and humoral immunity to native human type II collagen. Our results indicate that the presence of DR4 is not required for the development of autoimmunity to collagen in rheumatoid arthritis.
Extracellular presence of the lysosomal proteinase cathepsin B in rheumatoid synovium and its activity at neutral pH
Authors: Mort John S. , Recklies Anneliese D. , Poole A. Robin 
Published: February 2007

AbstractThe presence of the lysosomal proteinases cathepsin B and cathepsin D at extracellular sites in rheumatoid synovium was demonstrated using the antibody capture technique. Unlike cathepsin D, the cysteine proteinase cathepsin B was commonly detected only at the edges of the synovial explants. Radioimmunoassay and enzyme activity assay of these proteinases demonstrated that both were released from rheumatoid synovial cells in comparable amounts. Since lysosomal cathepsin B is unstable and denatured at physiologic pH and the antibody used only recognizes inactivated enzyme, we believe the selective detection of cathepsin B at the edge of the synovium may be due to the proteinase maintaining a native conformation within the explant, where the pH may be low enough to permit this. By use of a fluorescent substrate in a sensitive, continuous enzyme assay, cathepsin B was shown to express significant activity at neutral and alkaline pH before being inactivated. This and earlier work from this laboratory indicate that cathepsin B secreted by rheumatoid synovial cells may possess extracellular activity in vivo and be involved in the degradation of connective tissue macro‐molecules.
The use of trained patient instructors for teaching and assessing rheumatologic care
Authors: Gall Eric P. , Meredith Keith E. , Stillman Paula L. , Rutala Paul J. , Gooden M. Annell , Boyer John T. , Riggs Gail E. 
Published: February 2007

AbstractThe training of professionals in rheumatologic care requires review and study. To improve teaching methods, 6 patients with stable rheumatic disease were trained to evaluate and teach medical students by using themselves as models for musculoskeletal examinations. Checklists for scoring performance and content were developed. Criteria established to give evidence of the validity of the checklists and of the reliability of the patient instructors in their scoring were met or exceeded. The patient instructors are now an integral part of the Preparation for Clinical Medicine curriculum at our institution and serve as resources for evaluation and teaching in the continuing education of practicing professionals.
Connective tissue activating peptide III induction of synthesis and secretion of plasminogen activator by synovial fibroblasts
Authors: Ragsdale Carol Godoshian , Castor C. William , Roberts Dedra J. , Swartz Kenneth H. 
Published: February 2007

AbstractConnective tissue activating peptide III (CTAP‐III) is a platelet factor that induces, in cultured connective tissue cells, activities observed in chronic inflammation. In this study we measured plasminogen activator secretion by synovial fibroblasts after stimulation by CTAP‐III. Increased plasminogen activator secretion was observed 24—48 hours after stimulation. Induction was prevented by dexamethasone (10‐9—10‐7M), cycloheximide (1 μg/ml) and, variably, by actinomycin D (0.3 μg/ml), but not by cytosine arabinoside (10‐4M). This is the first evidence that CTAP‐III induces degradative as well as proliferative activity by connective tissue cells.
Susceptibility and resistance to 6‐sulfanilamidoindazole‐induced arthritis among inbred strains of rats
Authors: Samuelson Cecil O. , Griffiths Marie M. , Mathews Jeffrey L. , Clegg Daniel O. , Ward John R. 
Published: February 2007

AbstractInflammation induced by 6‐sulfanilamidoindazole (6‐SAI) in aged, outbred rats is predictably produced, but the pathogenesis is not understood. We demonstrate the variable resistance of 15 inbred rat strains to 6‐SAI arthritis. Susceptibility to 6‐SAI arthritis is not directly linked to the major histocompatibility complex, although resistance is related to the major histocompatibility complex in other experimental forms of rat arthritis. The genetic background of these inbred rat strains appears to have a major role in 6‐SAI arthritis susceptibility.
Rheumatoid myositis
Authors: Halla James T. , Koopman William J. , Fallahi Sohrab , Oh Shin J. , Gay Renate E. , Schrohenloher Ralph E. 
Published: February 2007

AbstractThirty‐one patients with rheumatoid arthritis were consecutively studied for evidence of muscle involvement, using muscle biopsy and electromyography. The patients were initially separated into 4 clinical categories: inactive peripheral joint disease (6 patients); active peripheral joint disease (10 patients); systemic disease and a disproportionately elevated sedimentation rate for the degree of mild synovitis (SERD) (11 patients); or elevated creatinine phosphokinase level (4 patients). In addition to routine histology, muscle tissue was examined for de novo synthesis of IgM and IgM rheumatoid factor, and by indirect immunofluorescence for the presence of immunoglobulin and complement deposits. Our results indicate that: 1) muscle fiber necrosis occurs frequently in patients with rheumatoid arthritis; 2) rheumatoid myositis, defined as muscle fiber necrosis and mononuclear cell infiltration, is a distinct entity and occurs particularly in patients with SERD or an elevated creatinine phosphokinase level; and 3) only muscle from patients with rheumatoid myositis exhibited de novo synthesis of rheumatoid factor and significant quantities of IgM, indicating that local immune events may be important in the pathogenesis of this entity.
Suppressor t cell function in patients with rheumatoid arthritis complicated by vasculitis
Authors: Abe Tohru , Takeuchi Tsutomu , Koide Jun , Hosono Osamu , Homma Mitsuo , Morimoto Chikao , Yokohari Ryuichi 
Published: February 2007

AbstractConcanavalin A (Con A)—induced suppressor T cell activity was determined in 10 rheumatoid arthritis (RA) patients with vasculitis, 34 RA patients without vasculitis, and 10 healthy individuals. The percent Con A—induced suppression in RA patients with vasculitis was 24.6. In contrast, it was 68.4% in those RA patients without vascular lesions. Further, the proportion of T cells reactive with OKT8 monoclonal antibody was also decreased in RA patients with vasculitis. Accordingly, the reduced Con A—induced suppressor T cell activity in these RA patients resulted, in part, from the reduction in the number of cells of the suppressor T cell subset. Those patients with vascular lesions also had a higher percentage of positive antilymphocytotoxic antibodies than RA patients without vasculitis. Since the differences in Con A—induced suppressor T cell activity and frequency of positive antilymphocytotoxic antibodies were so great, we believe RA patients with vasculitis could be recognized as a disease group distinct from RA patients without vasculitis.
Collagen‐induced and adjuvant‐induced arthritis in rats
Authors: Phadke Kalindi , Fouts Rebecca , Parrish John E. 
Published: February 2007

AbstractImmunization of Lewis rats with native type II collagen results in an inflammatory arthritis and increased humoral and cellular immune responses to type II collagen. The exposure of rats to native type II collagen at day 7 or 10 after immunization suppressed the incidence of arthritis and anticollagen antibody levels, although the cellular response was not affected. The exposure to denatured type II collagen offered partial protection, while type I collagen had no significant effect. Rats immunized with Mycobacterium tuberculosis also showed reduced arthritic response when subsequently treated with type II collagen. The common modalities between the 2 models and the possible role of type II collagen in the interference with the inflammatory arthritic events are discussed.
Quantitation of human synovial mast cells in rheumatoid arthritis and other rheumatic diseases
Authors: Godfrey Henry P. , Ilardi Carl , Engber William , Graziano Frank M. 
Published: February 2007

AbstractWe examined sections of synovial membranes from 14 patients with rheumatoid arthritis (RA), 7 with other rheumatic diseases, and 10 with no apparent joint disease. Patients with RA and other rheumatic diseases had significantly more synovial mast cells/vessel than patients with no joint disease (0.49 and 0.20, respectively, versus 0.03). They also had significantly more total mast cells/10 fields than patients with no joint disease (9.9 and 5.0, respectively, versus 0.4). Within the rheumatoid group, patients with active disease had more total mast cells/10 fields than patients clinically considered to have end‐stage disease (P < 0.05). Synovial basophils were not identified in any patient. Synovial vascularity was similar for all groups (2.3 vessels/field). The role of the synovial mast cell in RA and other rheumatic diseases remains to be determined.
Serum Clq levels as a prognostic guide to articular erosions in patients with rheumatoid arthritis
Authors: Ochi Takahiro , Yonemasu Kunio , Iwase Rokuro , Sasaki Takako , Tsuyama Kenichiro , Ono Keiro 
Published: February 2007

AbstractC1q was measured serially by single radial immunodiffusion in 54 rheumatoid arthritis (RA) patients over a period of more than 5 years, and values were correlated with laboratory, radiographic, and clinical findings. The number of joints with erosion (NJE) was determined retrospectively from radiographs of patients who had RA of >7 years duration. In patients with clinically “burned out” RA, C1q levels were not statistically different from those of healthy adults. During the period of active disease, each patient's C1q level remained very constant, irrespective of erythrocyte sedimentation rate, C‐reactive protein (CRP) level, or whether the RA was active or in remission. No sustained correlation was found between the C1q level and the other 2 acute phase reactants, but patients with C1q levels of at least 250 μ g/ml showed a positive CRP over a period of years, in contrast to those with C1q levels below 250 μ/ml. Patients with an initial C1q above 250 μ/ml had more erosive RA when compared with those having C1q levels below 250 μ/ml. These data suggest that active RA can be classified into two subsets by C1q levels, one with persistent inflammation and a high NJE and another without persistent inflammation and with a low NJE.
Experimental synovitis induced by intraarticular administration of α2‐macroglobulin‐proteinase complexes
Authors: Steffen Carl , Borth Wolfgang , Susani Martin , Zischka‐Konorosa Wilhelm 
Published: February 2007

AbstractRheumatoid synovial collagenase was prepared from tissue cultures from rheumatoid arthritis patients, obtained after synovectomy. Alpha2‐macroglobulin was isolated from human plasma and complexed with collagenase or trypsin. Formation of both types of complexes was proven by sodium dodecyl sulfate and rate electro‐phoresis. Normal rabbits were injected intraarticularly into the right knee, on days 0, 3, and 6, with either α2‐macroglobulin‐collagenase or α2‐macroglobulin‐trypsin complexes. Control injections of α2‐macroglobu‐lin, trypsin, or rheumatoid synovial collagenase were applied to the left knee joint cavity. Groups of rabbits were killed 18 hours, 1 week, or 3 weeks after the last injection, and cellular exudation into synovial fluid and morphologic alterations of synovium were investigated. Joints injected with collagenase showed no synovitis, while joints injected with collagenase showed an experimental synovitis. Alpha2‐macroglobulin‐proteinase complexes, however, induced a synovitis, which was more severe than that occurring after injection of proteinases only. In the early stages, synovium showed perivascular accumulation of inflammatory cells, infiltration with neutrophils, proliferation of synovial cells, and exudation of inflammatory cells into synovial fluid. Later stages were characterized by infiltration with mononuclear cells and fibroplasia.
Changes in proteoglycan biosynthesis following leukocyte elastase treatment of bovine articular cartilage in culture
Authors: Bartholomew Jennifer S. , Lowther Dennis A. , Handley Christopher J. 
Published: February 2007

AbstractTreatment of bovine articular cartilage in culture with a low molecular weight elastase purified from rabbit polymorphonuclear leukocytes resulted in degradation and release of proteoglycans from the tissue, coupled with a prolonged inhibition of proteoglycan biosynthesis. These observations are consistent with those seen in experimental arthritis induced in rabbits. Comparison of the size of the proteoglycan degradation products extracted from elastase‐treated cartilage in culture with that from arthritic cartilage showed marked similarities. The results strongly suggest that leukocyte elastase is a contributing factor in proteoglycan degradation and inhibition of synthesis in inflammatory joint disease.
A new serologic marker in ankylosing spondylitis
Authors: Lakomek Heinz‐Jürgen , Will Hans , Zech Michael , Krüskemper Hans Ludwig 
Published: February 2007

AbstractSera of patients with ankylosing spondylitis (AS) were screened for the presence of antibodies by indirect immunofluorescence staining of polytene chromosomes of Drosophila melanogaster. Thirty‐nine percent of the sera tested contained antibodies which selectively reacted with an antigen(s) present at the chromosomal locus 93D after heat shock treatment. This indicates a novel antibody specificity in a subgroup of AS patients and may provide a new aid in the diagnosis of AS.
Synthesis of electrophoretically restricted IgG by cultured rheumatoid synovium
Authors: Hoffman Wayne L. , Douglass Rita R. , Donald Smiley J. 
Published: February 2007

AbstractIgG synthesized by excised rheumatoid (RA) synovia was separated according to isoelectric point using chromatofocusing and isoelectric focusing. Over 30% of the IgG synthesized by 9 of 11 synovia had an isoelectric point >8 (cathodal shift), while 55% of the synovia secreted IgG showing oligoclonal banding by isoelectric focusing. Oligoclonal serum IgG was seen in 17% of RA patients and in only 3% of hospitalized patients without RA. These results emphasize the selective character of the antigenic stimulus of the RA synovial lymphoid infiltrate.
Decreased pokeweed mitogen‐induced igm and igm rheumatoid factor synthesis in rheumatoid arthritis patients treated with gold sodium thiomalate or penicillamine
Authors: Olsen Nancy J. , Jasin Hugo E. 
Published: February 2007

AbstractProspective and retrospective analysis of data obtained on 119 patients with rheumatoid arthritis suggested a relationship between clinical response induced by gold salts or D‐penicillamine and decreased in vitro antibody synthesis by peripheral blood mononuclear cells. A subgroup of 21 patients with inactive disease receiving these drugs was found to have decreased pokeweed mitogen‐induced in vitro synthesis of IgM and IgM rheumatoid factor. Detailed analysis of the cellular mechanisms responsible for this decreased responsiveness demonstrated markedly decreased B cell function. Patients treated with D‐penicillamine also had altered T cell helper function manifested by incomplete reconstitution of the normal IgM response, while patients treated with gold salts had normal T cell function. Monocytes appeared not to have a major role in the decreased in vitro responsiveness. The results suggest that, in patients who respond to gold salts or D‐penicillamine, antibody synthesis by circulating B cells is profoundly decreased, probably due to an indirect effect of these disease‐modifying agents.
Increased biosynthesis of glycosaminoglycans by scleroderma fibroblasts in culture
Authors: Bashey Reza I. , Millan Alberto , Jimenez Sergio A. 
Published: February 2007

AbstractFibroblasts from normal and scleroderma skin, grown in culture, were incubated with radioactive glucosamine to study the biosynthesis of glycosaminoglycans (GAG). Incorporation of 3H‐glucosamine and GAG biosynthesis was increased in 6 of 9 scleroderma fibroblast cultures examined. This increase ranged from 26 to 96% over normal values and was reproducible. Over 70% of the 3H‐glucosamine incorporated was found in the medium of the cultures, and this fraction was used to isolate GAG. Characterization of media GAG from normal and control cultures showed that about 80% of the radioactive GAG could be degraded by a specific fungal hyaluronidase; therefore, it represented hyaluronic acid. Our findings indicate that the majority of scleroderma dermal fibroblasts display increased biosynthesis of GAG in culture and that this increase is mostly in the hyaluronic acid fraction.
Clinical and pathologic studies of synovitis in polymyalgia rheumatica
Authors: Chou Chung‐Tei , Ralph Schumacher H. 
Published: February 2007

AbstractClinically detectable joint swelling was found in 10 of 13 fully evaluated patients considered to have polymyalgia rheumatica. Five patients had some joint findings at disease onset. Knees were most commonly affected. Sternoclavicular involvement was seen in 3 patients. Joint effusions in 8 patients had 300–5,700 leukocytes/mm3 with a mean of 2,900. Six synovial biopsy specimens studied by light microscopy revealed mild to moderate synovial proliferation and chronic inflammation that was generally less severe than in typical rheumatoid arthritis. Electron microscopy identified microvascular changes and large amounts of vesicular and granular debris in lining cells. In 1 patient, a “fingerprint” pattern in the granular material was suggestive of the findings in some immune complexes. This still unexplained synovitis may, as previously suggested, be important in the pathogenesis of the polymyalgia rheumatica syndrome.
Inhibitory effect of igm rheumatoid factor on immune complex solubilization capacity and inhibition of immune precipitation
Authors: Balestrieri Genesio , Tincani Angela , Migliorini Paola , Ferri Clodoveo , Cattaneo Roberto , Bombardieri Stefano 
Published: February 2007

AbstractPurified IgM rheumatoid factors (RF; 3 monoclonal and 2 polyclonal) were shown to inhibit, in a dosedependent manner, 2 complement‐mediated functions, i.e., the immune complex solubilization capacity and the inhibition of immune precipitation. Inhibition of immune complex solubilization capacity occurred only if RF was added at the same time as, but not after, addition of the complement source. Experimental evidence suggests that the effects of RFs were not related to their anticomplementary activity, but rather required the attachment of RF to the Fc region of the IgG molecule. Although no clinical data are available so far, it might be plausible that these newly described properties of RF have biologic relevance.
Cyclic nucleotides and calcium transport in cultured dermal fibroblasts from progressive systemic sclerosis and rheumatoid arthritis patients
Authors: Grozdova M. D. , Khokhlova J. V. , Panasyuk A. F. , Guseva N. G. , Trofimova T. M. 
Published: February 2007

AbstractLevels of cAMP were decreased and cGMP increased in progressive systemic sclerosis (PSS) fibroblasts compared with normal fibroblasts. PSS cells took up unusually large quantities of Ca++. The epinephrine‐induced increases in cAMP were diminished sixfold and epinephrine‐induced Ca++ uptake was abnormal in PSS cells. Considerable heterogeneity was observed in rheumatoid arthritis fibroblasts. Membrane‐bound abnormalities in (PSS) cells may be of importance in the defective control of collagen production in progressive systemic sclerosis.