Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0024141 (systemic lupus erythematosus)
 44,322 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A dynamic estimation of the involvement of the complement system in various diseases was obtained by the direct quantitation of breakdown products of C3 and of properdin factor B. The methods used were based, first on the separation of native and fragmented molecules according to their molecular size through a precipitation with polyethylene glycol and, secondly, on an immunochemical quantitation, using specific antisera for the major antigens of C3 and factor B. The sensitivity and the specificity of these methods were demonstrated by activation of complement in vitro with generation of C3 and factor B fragments. A clinical investigation was carried out in 41 patients with systemic lupus erythematosus (SLE), 31 with membranoproliferative glomerulonephritis (MPGN), 26 with other types of glomerulonephritis, and 6 with severe alcoholic cirrhosis of the liver. The following observations were made: (a) an elevated plasma level of C3d fragment of C3 was found in 68% of SLE patients, in 87% of MPGN patients, in 62% of patients with other hypocomplementemic nephritis, and in 15% of those with normocomplementemic nephritis, but in only 33% of patients with liver cirrhosis and very low levels of C3; (b) a significant difference was observed between the levels of C3 obtained with either anti-"native" C3 or anti-C3c sera for immunochemical quantitation, in patients with SLE or MPGN, indicating the presence of "altered" or fragmented C3 in plasma; (c) an elevated plasma level of Ba fragment of properdin factor B was found in 46% of SLE patients, in 67% of MPGN patients, in 50% of patients with other hypocomplementemic nephritis, and in 9% of patients with normocomplementemic nephritis, while the level of properdin factor B was only slightly decreased in these diseases; (d) in SLE and MPGN there was an inverse correlation between the levels of C3d and Ba and the level of C3 in plasma. The level of these fragments was directly correlated with the clinical manifestations of SLE; (e) some patients with a normal C3 level exhibited an elevated plasma concentration of C3 and factor B fragments, suggesting the coexistence of an increased synthesis with a hypercatabolism of complement components. Therefore, the quantitation of complement breakdown products by simple immunochemical methods provides additional information concerning the involvement of complement in disease and new features for the evaluation of the intensity of immune reactions during immune complex diseases.
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PMID:Complement breakdown products in plasma from patients with systemic lupus erythematosus and patients with membranoproliferative or other glomerulonephritis. 114 31

Circulating DNA has been associated with several human disorders, including the nephritis of systemic lupus erythematosus (SLE), in which it is thought to play an etiological role. However, it remains unclear whether its appearance in the circulation is truly pathological. Several reports, each generally based on a single assay method, have disagreed as to whether DNA may circulate in normals. Some, but not all, of this disagreement may be explained by the recently described appearance of DNA in serum, but not plasma, apparently as the result of release from leukocytes in vitro. In the present report an attempt is made to clarify this problem. Normal plasma and serum samples were examined by four assays for DNA that were newly modified to enhance their specificity and/or sensitivity. Plasma DNA was undetectable by all four methods, the most sensitive of which could detect 0.05 mug/ml of native DNA (nDNA) or 0.1 mug/ml of single-stranded DNA (ssDNA). Serum DNA was present in 14 of 16 samples tested in variable concentrations with an estimated mean of 1.9 mug/ml. It is concluded that the appearance of DNA in adult human plasma is a pathological event. Presumably, previous reports describing detection of DNA in normal plasma were based on the measurement of non-DNAase-sensitive interfering substance. Furthermore, it is emphasized that the use of serum in studies dependent on sensitive assays for DNA (or anti-DNA antibody) introduces an ambiguity that may be avoided by substitution of carefully collected plasma for serum.
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PMID:Free DNA in serum and plasma from normal adults. 115 Aug 82

Properdin deposition has been recognized in glomeruli of patients with acute and chronic nephritis and lupus nephritis, and low serum properdin levels have been found in these disorders. These findings suggest that properdin may be involved in the production of glomerular damage and that low properdin levels may be due to hypercatabolism. The study was designed to examine the metabolism of properdin in normal subjects and to look for an abnormality in five patients with systemic lupus erythematosus with renal involvement and in six patients with membranoproliferative glomerulonephritis or dense deposit disease (MPGN). Highly purified human properdin was prepared by elution from zymosan, followed by DEAE-cellulose and carboxymethyl-Sephadex chromatography, and labeled with 125I by the iodine monochloride method. Parameters of metabolism were determined by monitoring plasma and urinary radioactivity at frequent intervals after the intravenous injection of 1-2 muCi of labeled material. The fractional catabolic rate (FCR) of properdin in normal subjects was found to have a very narrow range of 0.78-1.0,% of the plasma pool per hour (mean 0.95%). In systemic lupus erythematosus, the FCR was regularly elevated with a range of 1.21-2.30% (mean 1.70%). In MPGN, FCR was elevated in three patients (1.22, 1.94, and 2.08%) and within or below the normal range in three (0.78, 1.00, and 1.00%). Properdin levels were reduced in two patients who had the highest FCR's noted in the study. Properdin synthetic rates in normals varied from 4.1 to 14.3 mug/kg per h (mean 9.1) and was not found to be reduced in any patient. Properdin catabolism was found to be normal in a patient deficient in the C3b inactivator. These studies show that properdin is hypercatabolized in patients with renal disease and that decreased properdin levels when they occur in these patients can be entirely explained on the basis of this hypercatabolism.
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PMID:Metabolism of properdin in normal subjects and patients with renal disease. 115 85

Hematoxylin bodies, the pathognomonic light microscopic feature of systemic lupus erythematosus commonly found in renal glomeruli affected with active nephritis, are described in renal tubular epithelium. Formerly thought to be the result of "L.E. transformation" of these cells, a proposed mechanism of this phenomenon is that hematoxylin space are phagocytosed by tubular epithelial cells. This would explain the observation in the case presented and also that of the single previous report of this unusual feature.
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PMID:Hematoxylin bodies: their appearance in renal tubular epithelium. 118 96

Three cases of cardiac valvular disease complicating chronic inflammatory disorders of connective tissue are described. Each underwent surgical valve replacement. The outcome in the first case, a patient with aortitis complicating Reiter's syndrome and in good health otherwise, has been excellent. The other two patients, one with rheumatoid arthritis and vasculitis, the other with systemic lupus erythematosus and nephritis, died after operation as the result of their systemic disease. The importance of systemic features in assessing this type of patient is emphasized.
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PMID:Cardiac valvular disease in chronic inflammatory disorders of connective tissue. Factors influencing survival after surgery. 119 Aug 52

To study the participation of the antibody avidity in the pathogenesis of lupus nephritis, we measured the antibody avidity to native DNA by the method of Minden and Farr (14) in patients with SLE. The avidity to native DNA was almost less than 40%. The avidity and the histological activity of lupus nephritis were well correlated; the antibody avidity of the active-group sera was higher than that of the inactive-group sera and the group without nephritis. In the group with antibodies of relatively high avidity, the complexes were deposited mainly in the subendothelial side of GBM and in the mesangium. On the other hand, in the group with low-avidity antibodies, the complexes were localized in the subepithelial side of GBM. On investigating the quality of the complexes, we noted that the complexes composed of high-avidity antibodies prepared in vitro were larger than those of low avidity and the former were larger than 19S. If the native-DNA-anti-native DNA system is the mechanism basic to lupus nephritis, the differences in immune response of the host, namely the degree of antibody avidity may greatly affect complex formation and influence the histological activity and nephritogenicity of lupus nephritis.
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PMID:Antibody avidity for native DNA in lupus nephritis. 123

1. Platelet survival and an index of the localization of platelets in the kidney were studied in patients with the proliferative nephritis of systemic lupus erythematosus, either focal or diffuse, and in control subjects. Platelet survival was reduced in patients with proliferative lupus nephritis, more in those with diffuse rather than focal renal involvement. 2. The index of renal platelet localization in patients with diffuse proliferative nephritis suggested an intrarenal platelet consumption not found in other groups. 3. A patient with the classical platelet autoantibody disease, idiopathic thrombocytopenic purpura, also showed reduced platelet survival but localization of platelets was in the spleen rather than the kidney. 4. Intrarenal platelet consumption in diffuse proliferative lupus nephritis may be an epiphenomenon of pre-existing scarring or platelet aggregation secondary to immune complex-formation, which contributes to the progressive sclerosing lesions of this form of nephritis.
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PMID:Intrarenal platelet consumption in the diffuse proliferative nephritis of systemic lupus erythematosus. 123 81

61 biopsies of normal skin from the deltoid area and lesional skin from various sites from 48 patients with systemic lupus erythematosus (SLE) were studied for the presence of properdin, C3, C4, and immunoglobulins (IgG, IgM, and IgA) in the dermal-epidermal junction (DEJ) using direct and indirect immunofluorescence. Properdin was present in 50% of normal and 40% of lesional skins. Properdin was present without C4 in only 2 of 38 nonlesional skin biopsies and in only 2 of 20 lesions. There was no significant difference in incidence of deposition of any of the six proteins studied between nonlesional and lesional skin. The frequency of deposition of each of the proteins correlated with clinical disease activity. The presence of proteins in the DEJ did not correlate with the presence of active renal disease at the time of biopsy nor with previously documented active nephritis. In addition, no other single clinical manifestation correlated with the presence of DEJ deposition of any protein studied. IgA was not demonstrated in the DEJ of nonlesional skin of 16 patients in remission and was present in 7 of 23 patients with active disease (P less than 0.05). Deposition of properdin in lesional skin correlated with the presence of extracutaneous disease activity (P less than 0.05). Analysis of serologic studies on serum obtained at the time of biopsy revealed a statistically significant correlation between C4 and C3 (r = 0.67). This correlation was stronger than that between properdin and C4 (r = 0.37). Titer of antinuclear antibody and percent of DNA binding correlated better with C4 levels than with properdin levels. Serum properdin levels were significantly lower in patients with active disease than in those in remission (P less than 0.05). Serum properdin levels were significantly lower in patients with properdin deposits in lesional skin than in those without properdin deposits. The data suggest that both alternative and classical pathways are activated in patients with clinically active SLE.
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PMID:Clinical significance of serum properdin levels and properdin deposition in the dermal-epidermal junction in systemic lupus erythematosus. 124

The changing pattern of mortality in systemic lupus erythematosus (SLE) led to an examination of the deaths in a long-term systematic analysis of 81 patients followed for five years at the University of Toronto Rheumatic Disease Unit. During the follow-up 11 patients died; six patients died within the first year after diagnosis (group I) and five patients died an average of 8.6 years (from 2.5 to 19.5 years) after diagnosis (group II). In those who died early, the SLE was active clinically and serologically, and nephritis was present in four. Their mean prednisone dose was 53.3 mg/day. In four patients a major septic episode contributed to their death. In those who died late in the course of the disease, only one patient had active lupus and none had active lupus nephritis. Their mean prednisone dose was 10.1 mg/day taken for a mean of 7.2 years. In none was sepsis a contributing factor to their death. All five of these patients had had a recent myocardial infarction at the time of death; in four, ti was the primary cause of death. Mortality in SLE follows a bimodal pattern. Patients who die early in the course of their disease, die with active lupus, receive large doses of steroids and have a remarkable incidence of infection. In those who die late in the course of the disease, death is associated with inactive lupus, long duration of steroid therapy and a striking incidence of myocardial infarction due to atherosclerotic heart disease.
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PMID:The bimodal mortality pattern of systemic lupus erythematosus. 125 49

Virtually all preparations of DNA used to detect antibody to native DNA (nDNA) by binding assays have been found to be subtly contaminated by single stranded DNA. Because recent DNA binding data have directly challenged the unique role previously attributed to these antibodies in systemic lupus erythematosus (SLE), resolution of the consequent ambiguity is of theoretical and practical importance. It is proposed that a synthetic nDNA molecule (dAT) might circumvent this difficulty by being antigenically equivalent to nDNA while, on theoretical grounds, lacking significant contamination with single stranded DNA or other cellular antigens. These expectations were generally confirmed by biochemical and immunological analyses. In clinical studies, sera from 124 pateints with SLE and from controls were examined for their ability to bind dAT. In contrast to results with KB binding, patients with non-SLE rheumatologic disorders were indistinguishable from normals by dAT binding. dAT binding was elevated in 85% of sera from SLE patients with clinically-judged active nephritis but in only 9% of those with inactive renal disease. Active non-renal disease, including cerebritis, was not associated with increased dAT binding. Individual non-lupus sera which bound increased amounts of KB DNA, failed to bind dAT. It is suggested that such binding resulted from contaminating non-nDNA antigens. When elevated, dAT binding, like KB binding, varied with disease activity and might thus be useful as a parameter thereof. In several patients elevated dAT binding led to the finding, on biopsy, of clinically silent, active, diffuse proliferative nephritis. It is concluded that use of synthetic nDNA antigens such as dAT may offer theoretical and practical advantages over naturally-derived preparations in detecting anti-nDNA, both clinically and for investigational purposes. Also, caution is urged in interpreting DNA binding data derived from incompletely characterized systems, particularly with regard to the occurrence of anti-nDNA antibodies in serum.
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PMID:Detection of anti-DNA antibody using synthetic antigens. Characterization and clinical significance of binding of poly (deoxyadenylate-deoxythymidylate) by serum. 126 74


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