Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003864 (arthritis)
 69,039 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Rat peritoneal macrophages stimulated in vivo by group A streptococcal peptidoglycan-polysaccharide (PG-APS) resorb bone as measured by solubilization of 45Ca from radiolabeled, devitalized bone chips. Activity was strain-dependent and correlated with the susceptibility of rat strains to PG-APS-induced arthritis. PG-APS-stimulated macrophages from the resistant Buf rat strain were not induced to resorb bone, but ingested equivalent concentrations of PG-APS compared to bone-resorbing macrophages from the arthritis-susceptible Lew strain. Resorptive activity peaked at three to five days and decreased to background levels by 10 days after injection. PG-APS-stimulated macrophages from congenitally athymic Lew rats were as effective as macrophages from heterozygous littermates at resorbing bone. Lew macrophages were also responsive to small, nonarthropathic PG-APS polymers generated by mutanolysin digestion. Resident peritoneal macrophages did not respond to stimulation by PG-APS in vitro. Indomethacin at a concentration of 10 micrograms/ml was an effective blockade against PG-APS-induced macrophage bone resorption in vitro, but catalase was ineffective. These results indicate that expression of rat macrophage bone-resorbing activity reflects genetic regulation of the response to PG-APS rather than a defect in ingestion of these polymers and imply that PG-APS-stimulated, bone-resorbing macrophages may contribute to early, initial bone destruction that occurs in inflammatory arthritis.
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PMID:Bone-resorbing activity is expressed by rat macrophages in response to arthropathic streptococcal cell wall polymers. 142 23

A specific interleukin-1 (IL-1) receptor antagonist (IL-1ra) was used to examine the roles of IL-1 in an experimental model designed to analyze the reactivation phase of erosive arthritis, induced in rats with peptidoglycan-polysaccharide polymers (PG-APS) isolated from cell walls of group A streptococci. Monoarticular arthritis was initiated by injection of a small dose of PG-APS into an ankle joint, and reactivation was induced by intravenous injection of PG-APS 20 days later. Human recombinant IL-1ra given at a dose of 2 to 3 mg/kg at the time of reactivation of arthritis and at 6-h intervals inhibits the increase in joint swelling by at least 60%. Joint swelling is suppressed 30 to 50% when the initial treatment with IL-1ra is delayed until 6 h after reactivation. IL-1ra is not effective when the initial injection is delayed 12 or 24 h. With an injection schedule of IL-1ra given at the time of reactivation and every 6 h, treatment can be stopped at 24 h and the suppression of swelling is no different from that in rats for which injections are continued for 4 days. The results indicate that IL-1 has a prominent, although not exclusive, role in initiating inflammation in this model and is involved in the amplifying processes in progressive inflammation and chronic erosive disease. An anti-inflammatory function of IL-1 is also indicated from data showing that IL-1ra treatment limited to 6 h or less after the induction of reactivation enhances joint swelling, whereas intravenous injection of human recombinant IL-1 beta 24 h before reactivation suppresses the reactivation of arthritis.
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PMID:Pro- and anti-inflammatory roles of interleukin-1 in recurrence of bacterial cell wall-induced arthritis in rats. 183 76

The plasma kallikrein-kinin system is activated in Gram-negative sepsis and typhoid fever, two diseases in which bacterial products have been shown to initiate inflammation. Because a single intraperitoneal injection of bacterial cell wall peptidoglycan-polysaccharide polymers from group A steptococci (PG-APS) into a Lewis rat produces a syndrome of relapsing polyarthritis and anemia, we investigated changes in the role of the kallikrein-kinin system in this model of inflammation. Coagulation studies after injection of PG-APS revealed an immediate and persistent decrease in prekallikrein levels. High-molecular-weight kininogen levels decreased significantly during the acute phase and correlated with the severity of arthritis. Factor XI levels were decreased only during the acute phase. Antithrombin III levels remained unchanged, indicating that neither decreased hepatic synthesis nor disseminated intravascular coagulation caused the decreased plasma contact factors. Plasma T-kininogen (an acute phase protein) was significantly elevated during the chronic phase. PG-APS failed to activate the contact system in vitro. Thus the kallikrein-kinin system plays an important role in this experimental model of inflammation, suggesting that activation of this system may play a role in the pathogenesis of inflammatory bowel disease and rheumatoid arthritis in which bacterial products might be etiologically important.
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PMID:Role of kallikrein-kinin system in pathogenesis of bacterial cell wall-induced inflammation. 199 42

The efficiency of a pure carbon prosthesis to reconstruct intra-articular ligamentous loss of substance was evaluated on 14 sheep with an 18-month follow-up study of recent and old ACL experimental injuries. Functional results showed a correlation between a tightened implant, the stability of the knee, and the absence of severe arthritis. The rupture strength of the newly formed ligament amounts to about 300 Newtons (N). That of the normal ACL amounts to 250-550 N. The structure gives a viscoelastic behavior to the prosthesis. This tissue was made of collagen fibers surrounding the carbon fibers and running generally in the direction of the ligament. In the osseous tunnels, the newly formed lamellar bone invaded and surrounded the implant. Carbon fiber fragmentation occurred, and fibers were found in the synovia and in the homolateral, inguinal, and paraaortic lymph nodes. No degeneration, necrosis of tissue, or cellular toxicity was found. On these bases, the carbon prosthesis was modified by adding a resorbable copolymer of polyglycollic (PGA) and polylactic acid (PLA) around the fibers and a resorbable sheath of the same polymer. This carbon-PGA/PLA prosthesis was used in 23 patients with a three- to 12-month follow-up period. Patients were evaluated by clinical tests and by functional control of the ligament. The indications for prosthetic replacement were: recent mop-end tears of the ACL, cruciate ligament reconstruction in chronic knee instability, and wide rotator cuff loss of substance. Five complications occurred because of hematomas and/or sepsis and prosthesis breakage. Eighteen of 23 patients had good clinical results with good function in five. The conclusions are that PGA/PLA produces a clean and flexible ligament, thus eliminating carbon fiber articular deposits and allowing a normal function. Inflammatory postoperative reactions seem to be more frequent than with other procedures and call for operative and clinical care in order to eliminate hematoma and sepsis. The efficiency of a rehabitable carbon-PGA/PLA prosthesis in intra-articular ligamentous defects in man will be confirmed only by controlled long-term clinical observations.
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PMID:Carbon-PGLA prostheses for ligament reconstruction. Experimental basis and short-term results in man. 298 86

Rats injected with peptidoglycan-polysaccharide polymers derived from group A streptococcal cell walls (PG-APS) develop a chronic, remittant, erosive synovitis. Spleen cells from injected rats failed to proliferate when stimulated in vitro by Con A or PHA, unless nylon wool adherent cells were first removed. The suppression could also be reversed by removing phagocytic cells which had ingested carbonyl iron. Cells from control rats were suppressed in vitro by co-culture with unfractionated or nylon wool-adherent cells from PG-APS injected rats, and the suppressor activity was still expressed after exposure of the suppressor cells to 3,000 rad of irradiation. Addition of catalase and indomethacin to cultures only partially reversed the suppression. T lymphocytes from rats given a single arthropathic dose of PG-APS remained suppressed for at least 86 days after injection. Cells from rats given a low, non-arthropathic dose of PG-APS did not become suppressed. Cells from the Buffalo rat, which is resistant to development of PG-APS-induced chronic arthritis, showed less suppression than cells from the susceptible Lewis and Sprague-Dawley rat strains.
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PMID:Immunosuppressive macrophages induced by arthropathic peptidoglycan-polysaccharide polymers from bacterial cell walls. 306 53

The arthropathic activity of mouse recombinant IL-1 (mrIL-1) after intraarticular (i.a.) injection into rat ankles was investigated. Nanogram quantities of either mrIL-1 alpha or mrIL-1 beta induced an acute transient arthritis. Arthritis induced by i.a. mrIL-1 developed more rapidly and was more severe in ankles previously injured by i.a. injection of group A streptococcal peptidoglycan-polysaccharide (PG-APS) fragments. In addition, a protracted pain response, as judged by severe limping, occurred 60 to 90 min after mrIL-1 injection into joints previously injured by PG-APS or 4 to 6 h after mrIL-1 injection into naive joints. The severity of arthritis was related to the mrIL-1 dose. Arthropathic activity of mrIL-1 alpha was neutralized by goat anti-mouse IL-1 alpha IgG, and the activity of both the alpha and beta preparations was heat labile. Repeated episodes of acute inflammation were induced by repeated i.a. injection of mrIL-1. In naive ankles this led to chronic synovitis without histologic evidence of erosions. However, in joints previously injured by PG-APS, repeated mrIL-1 injection induced a more severe chronic synovitis with a 50% incidence of early pannus formation and limited marginal erosions of cartilage and subchondral bone. Thus, mrIL-1 induces an acute exacerbation of arthritis in joints previously injured by PG-APS and repeated exposure of these joints to mrIL-1 promotes chronic erosive synovitis. These studies provide evidence for an in vivo function of IL-1 and are consistent with its role as one of the mediators in the local regulation of inflammation in recurrences of arthritis induced by bacterial cell wall polymers.
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PMID:Exacerbation of arthritis by IL-1 in rat joints previously injured by peptidoglycan-polysaccharide. 328 41

Rat ankle joints injected intraarticularly with 5 micrograms of group A streptococcal peptidoglycan-polysaccharide (PG-APS) developed an acute course of arthritis. Recurrence of arthritis was induced in 100% of these joints by intravenous injection of as little as 10 micrograms of Salmonella typhimurium lipopolysaccharide (LPS) 3 wk after intraarticular injection. This reaction was similar in athymic and euthymic rats. Buffalo rats were less susceptible than Lewis or Sprague-Dawley rats. Neisseria gonorrhoeae, Yersinia enterocolitica, and Escherichia coli LPS, and S. typhimurium Re mutant LPS, were also active. Re mutant LPS activity was greatly reduced by mixing with polymyxin B. E. coli lipid A was weakly active. An acute synovitis of much less incidence, severity, and duration was seen in contralateral joints injected initially with saline, and in ankle joints of naive, previously uninjected rats after intravenous LPS injection. The intravenous injection of the muramidase mutanolysin on day 0 or 7 after intraarticular PG-APS injection prevented LPS-induced recurrence of arthritis. These studies suggest that the phlogistic activities of lipid A and peptidoglycan might interact in an inflammatory disease process, and that LPS may play a role in recurrent episodes of rheumatoid arthritis or reactive arthritis.
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PMID:Lipopolysaccharide induces recurrence of arthritis in rat joints previously injured by peptidoglycan-polysaccharide. 329 8

Cell wall polymers isolated from group A streptococci, as well as lipopolysaccharide from Salmonella typhimurium and synthetic muramyl dipeptide, were injected into the ankle joints of rats. The inflammatory responses were assessed by gross and histologic examination, and edema was measured by accumulation of radiolabeled albumin in the limbs. The isolated group-specific polysaccharide induced extensive edema of the articular and periarticular tissue immediately after injection, and this resolved in 24 hours. The peptidoglycan moiety did not produce early edema, but induced an acute exudative reaction followed by a proliferative synovitis which resolved after 5 days. Reactions induced by covalently bound complexes of peptidoglycan and the group-specific polysaccharide (PG-APS) varied, depending on the size of the complex. Small fragments, derived from mutanolysin digestion, caused both an acute edematous reaction and transient arthritis. Larger fragments did not cause the immediate edematous reaction, but induced an acute arthritis that appeared within 24 hours and evolved into a chronic process. Episodes of recurrent inflammation, a distinctive feature of joint inflammation induced by systemic injection of PG-APS polymers, were not observed following intraarticular injection of any of the cell wall polymers. The relative susceptibility of different rat strains to arthritis induced by intraarticular injection paralleled the responses to systemic injection of PG-APS. These results demonstrate that variations in arthropathogenicity are due, in part, to inherent differences in the phlogistic activities of different cell wall polymers, and that the genetic control of susceptibility involves regulation of the inflammatory responses rather than the quantity of cell wall distributed to the joint.
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PMID:Comparison of inflammatory reactions induced by intraarticular injection of bacterial cell wall polymers. 351 27

The muralytic enzyme mutanolysin can act in vivo to eliminate chronic erosive arthritis induced in rats by polymers of peptidoglycan-polysaccharide isolated from group A streptococci (PG-APS). The amounts of PG-APS in the livers and spleens of rats treated with mutanolysin were significantly reduced compared with the amounts in control rats treated with phosphate-buffered saline. However, the amounts of PG-APS in the limbs of mutanolysin- and phosphate-buffered saline-treated rats were comparable. PG-APS polymers extracted from the livers, spleens, and limbs of mutanolysin-treated rats were extensively degraded, whereas PG-APS extracted from phosphate-buffered saline-treated rats had a high molecular weight. We propose that mutanolysin abrogates arthritis in rats by degrading PG-APS polymers to a size which is no longer able to induce chronic erosive arthritis, even though the polymers are still present in the limbs.
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PMID:In vivo degradation of bacterial cell wall by the muralytic enzyme mutanolysin. 351 73

Rats given a single intraperitoneal injection of an aqueous suspension of peptidoglycan-polysaccharide polymers derived from group A streptococcal cell wall (PG-APS) develop a severe, chronic, erosive arthritis which resembles human rheumatoid arthritis. The treatment of PG-APS-injected rats with a single intravenous injection of 0.4 mg of mutanolysin prevents the development of chronic arthritis, even when administration of the enzyme is delayed until severe acute arthritis has developed. PG-APS activates complement both in vitro and in vivo. Digestion of PG-APS with mutanolysin in vitro destroys the ability to activate both the alternate and classical pathways of human serum complement, and the loss of complement activation parallels the extent of PG-APS degradation. There is also a reduction in the in vivo complexing of C3 with PG-APS in the limbs of PG-APS-injected rats treated with mutanolysin, compared to control rats injected with PG-APS and treated with phosphate-buffered saline. This association between loss of arthropathic activity and loss of activation of complement is consistent with the hypothesis that activated complement products form a part of the inflammatory mediators involved in the acute and chronic phases of bacterial cell wall-induced arthritis. This may also partially explain how mutanolysin treatment alleviates cell wall-induced arthritis in the rat.
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PMID:Effect of muralytic enzyme degradation of streptococcal cell wall on complement activation in vivo and in vitro. 355 78


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