Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0003873 (rheumatoid arthritis)
 53,068 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to selectively remove pathogenic macromolecular reactants, a biological affinity type adsorbent (a DNA colloidin charcoal column or protein A sepharose CL4B = Prosorba) has been developed and used for the treatment of immune disorders, alloimmunization and cancer. However, because physiologically active materials are required in this procedure, it is difficult to ensure an adequate supply of raw materials (and their handling, sterilization and preservation as an immunoadsorbent. To overcome the above-mentioned problems, we developed physicochemical type immunoadsorbents IM-TR and IM-PH, which consist of polyvinyl alcohol gel where tryptophan, in the former, and phenylalanine, in the latter, is used as a ligand. IM-PH has a better selectivity than IM-TR, however, IM-TR is a more efficient adsorbent of anti-acethylcholine receptor antibody than IM-PH. IM-PH plasma perfusion has been successfully used with patients with rheumatoid arthritis, systemic lupus erythematosus (SLE), and multiple sclerosis (MS).
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PMID:Extracorporeal immunoadsorption with IM-PH or IM-TR column. 267 26

Evidence for free radical involvement in pathological processes is often indirect and frequently depends upon the detection of characteristic changes in tissue constituents, particularly polyunsaturated lipids. Free radical attack on protein leads to specific oxidative changes in their constituent amino acids, principally cysteine, tryptophan and tyrosine. This is associated with the induction of characteristic fluorescence (excitation 360 nm, emission 454 nm) and protein aggregation. This observation leads to a suitable assay for studying protein oxidation, and such fluorescent proteins may be relevant in the pathogenesis of diabetic microangiopathy and rheumatoid arthritis.
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PMID:Protein fluorescence and its relationship to free radical activity. 330 75

Tryptophan, its metabolites and related enzyme activity in synovial fluid, blood and urine in patients with rheumatoid arthritis (RA) and osteoarthritis (OA) were measured. The levels of tryptophan, kynurenine and anthranilic acid in the synovial fluid higher in RA were than in OA, whereas the xanthurenic acid level was equal in RA and OA. Indoleamine 2, 3-dioxygenase activity in the synovial membrane was higher in RA than in OA. 5-Hydroxytryptamine (5-HT) levels in the synovial fluid and the blood and the 5-hydroxyindole acetic acid (5-HIAA) level in the synovial fluid were essentially the same for both diseases. However, the 5-HIAA level in the serum of RA patients was higher than in those with OA, and the 5-HIAA level in the urine of RA patients was lower than in those with OA. In addition, monoamine oxidase-A and B activity in the synovial fluid of RA patients was decreased than in those with OA. These findings suggest that metabolism of tryptophan is altered in patients with RA.
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PMID:Alteration of tryptophan metabolism in the synovial fluid of patients with rheumatoid arthritis and osteoarthritis. 350 May 30

The concentrations of free and protein-bound L-tryptophan were measured in sera from normal subjects, patients with rheumatoid arthritis, pregnant women, and patients with jaundice. In the patients with rheumatoid arthritis receiving treatment with one or more antirheumatic drugs the percentage of the amino-acid bound to the circulating proteins was significantly depressed and in one patient returned to normal when therapy was stopped. Pregnancy and jaundice were also associated with raised free tryptophan and decreased bound tryptophan concentrations and bilirubin displaced the amino-acid from its binding sites on human serum proteins in vitro. It is suggested the behaviour of tryptophan mimics that of certain peptides which protect susceptible tissues against chronic inflammatory insults.
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PMID:Mode of action of antirheumatic drugs. 555 51

This volume details the history of vitamin B6, its chemistry and biochemistry, methods for the assessment of vitamin B6 status, and the clinical chemistry of the vitamin. Since its discovery and synthesis over 40 years ago, vitamin B6 has been implicated in a number of disease states. All approaches to the assessment of vitamin B6 status--direct measurement of blood levels, measurement of the excretion rate of the vitamin, measurement of the metabolites or abnormal metabolic products resulting from a deficient state, or measurement of some other process dependent on the concentration of the vitamin in the body--have significant technical or physiological problems. Dietary allowances vary for different age groups and situations. In the US, the National Academy of Sciences has recommended a daily dietary allowance of 2.2 mg for young adult males and 2.0 mg for young adult females. Additional allowances have been suggested for women during pregnancy and lactation, but not for users of oral contraceptives (OCs). Vitamin B6 deficiency can be either exogenous (when intake falls below the recommended dietary allowance) or conditioned (in cases where the physiologic requirement for the vitamin is higher than the dietary allowance). Conditioned deficiency arises in the following situations: defective intestinal absorption, defective cellular and intercellular transport, and impaired oxidtion or phosphorylation mechanisms in vitamin B6 metabolism. Studies aimed at assessing the abnormal tryptophan metabolism observed in some OC users have produced conflicting results. It appears that severe depression and impairment of glucose tolerance are the only important abnormalities encountered in OC users related to vitamin B6 deficiency. Abnormalities of tryptophan metabolism have been noted in patients with rheumatoid arthritis, some malignant diseases, liver disease, diabetes mellitus, atherosclerosis, and hyperkinetic syndromes.
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PMID:Clinical chemistry of vitamin B6. 639 13

The prevalence of cataracts is significantly lower in patients with rheumatoid arthritis receiving aspirin (mean of 2,700 mgs daily for an average of 10.4 years) as compared to the matched population not receiving aspirin. Similarly, fewer cataracts were found among a population with diabetes and rheumatoid arthritis receiving aspirin (mean of 2,340 mgs daily for an average of 8.8 years) as compared to the matched population on no aspirin. The effects of aspirin on cataract formation may result from 1) lowering of plasma tryptophan levels and increased excretion of tryptophan metabolites, 2) inhibition of aldose reductase and sorbitol formation in the diabetic lens, 3) inhibition of tryptophan or kynurenine binding to lens protein.
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PMID:Aspirin effect on cataract formation in patients with rheumatoid arthritis alone or combined with diabetes. 726 27

Neopterin and biopterin are two products of the pteridine pathway. Even though their roles and interrelationships have not been exactly clarified, neopterin is known as a biomarker of cell-mediated immunity. In this case, the highly elevated neopterin levels are parallel to the slightly elevated biopterin levels. On the other hand, the reduced form of biopterin-tetrahydrobiopterin is an essential cofactor of aromatic monoxygenases that leads to synthesis of tyrosine, tryptophan and dopamine neurotransmitters and its concentration in body fluids and tissues is maintained by the enzyme dihydropteridine reductase (DHPR). Increased numbers of activated lymphocytes can be found in peripheral blood, in the synovial fluid and synovial membranes or patients with rheumatoid arthritis (RA). Since the present study was undertaken to evaluate the role of the pteridine pathway in RA, we measured urine neopterin levels and dried blood DHPR activities in 36 patients with RA and in 20 healthy volunteers, in parallel with other clinical parameters. We found that neopterin excretion was significantly increased in RA patients compared with controls. The means were 433 +/- 216, 153 +/- 43 and 111 +/- 34 mumol/mol creatinine for patients in active stage, in remission and controls, respectively. Our results suggest that urine neopterin levels were strongly dependent on the stage and activity of RA. Either as an effect of the disease itself or of drug administration, slightly reduced DHPR activities were detected (3.484 +/- 0.304 for control, 2.974 +/- 0.255 in active stage RA, and 3.048 +/- 0.302 red cytochrome C/min/5 mm disc in remission).
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PMID:Urinary neopterin excretion and dihydropteridine reductase activity in rheumatoid arthritis. 983 51

CRF is both a peripheral and a central mediator of inflammation, the activity of which is modified by the presence of a 37-kDa binding protein (CRF-BP). The objective of this study was to measure and characterize this protein in the synovial fluid of rheumatoid arthritis patients and to observe the effects of this inflammatory condition on its structure and properties. Measured by immunoradiometric assays, the mean CRF-BP concentration in synovial fluid from 27 arthritic patients was 0.51 nmol/L (SD = 0.24 nmol/L); that for CRF was 6.31 pmol/L. The mean plasma concentration of CRF-BP in 24 control subjects was 1.38 nmol/L (SD = 0.35 nmol/L) and that for 10 arthritic patients was 2.89 nmol/L (SD = 0.84 nmol/L). Synovial fluids were found by immunoblotting to contain intact CRF-BP and a 10-kDa C-terminal CRF-BP fragment; synovial fluid from healthy controls was not examined. We previously reported that after purification of recombinant CRF-BP, spontaneous cleavage frequently occurs, resulting in a 27-kDa N-terminal and a 10-kDa C-terminal fragment. Because concentrations of native CRF-BP in synovial fluid were insufficient to study the effects of cleavage on ligand binding, they were determined using recombinant human CRF-BP. Tryptophan excitation fluorescence spectra of intact and cleaved recombinant CRF-BP revealed that cleavage was accompanied by conformational change in the N-terminal fragment, leading to exposure of the sole tryptophan residue to polar molecules (emission peak shift from 310 to 250 nm). Using gel filtration chromatography to separate the N- and C-terminal fragments, it was found that the N-terminal fragment of the recombinant protein bound human CRF, although dimerization was somewhat impaired. The C-terminal fragment did not bind CRF. Scatchard analysis confirmed that the affinity of both intact and cleaved CRF-BP for CRF was 1 x 10(10) L/mol. We conclude that synovial fluid contains intact CRF-BP in molar excess to CRF and fragmented CRF-BP. The significance of cleavage and the role of cleavage products have yet to be determined, although they may represent the generation of a novel bioactivity.
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PMID:Cleavage of recombinant human corticotropin-releasing factor (CRF)-binding protein produces a 27-kilodalton fragment capable of binding CRF. 1044 81

Within the wider framework of our studies on the genesis of rheumatoid arthritis we have investigated the two signal processes in arthritis: adenoribosylation of proteins and DNA methylation. Arthritis can be induced when Freund's complete adjuvant is applied to rats. This form of arthritis can then be reduced or even totally suppressed through the application of several different substances. In the present article we have investigated if the effect of two of these substances, 5-azacytidine and methotrexate can be influenced by the application of tryptophan plus methionine. When applied singly, these latter two substances are known to reduce the formation of arthritis. This effect is intensified by a combination of tryptophan plus methionine. Application of tryptophan plus methionine without methotrexate or 5-azacytidine causes an enhanced development of an adjuvant induced arthritis.
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PMID:The effect of tryptophan plus methionine, 5-azacytidine, and methotrexate on adjuvant arthritis of rat. 1046 58

Synovial fluids (SF) from patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), gout, and osteoarthritis (OA) were investigated for the levels of interleukin (IL)-1 beta, IL-6 and IL-8, tryptophan (Trp) and indoleamine 2,3-dioxygenase (IDO) activity. Significant differences exist in the levels of IL-1 beta between inflammatory arthritides RA, PsA and gout and non inflammatory arthritis, such as OA. The highest concentration of IL-1 beta was found in RA, that showed high levels also of IL-6 and IL-8. In the same disease we also found the highest IDO activity and the lowest Trp concentration. In addition, IDO activity seems to be related with the decrease in Trp, as demonstrated by the inverse correlation found between these two substances in the SF of all patients.
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PMID:Tryptophan catabolism in synovial fluid of various arthropathies and its relationship with inflammatory cytokines. 1072 Nov 1


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