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Results for “Complement C4”

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At least 1,621 records · Page 90Linked to original sources
PubMed1992

[Predictive value of non-specific signs of fetal infection in congenital toxoplasmosis].

AIMS: To study the predictive value of 9 non-specific signs for congenital toxoplasmosis. METHOD: The work was carried out as a prospective study comparing non-specific signs in 22 fetuses infected with toxoplasmosis and 59 fetuses free of the disease. RESULTS: Four of the nine parameters were found to be statistically higher in the group of infected fetuses. These are the level of leucocytes (p < 0.05) gamma glutamyl transferase (p < 0.001) total M immunoglobulin (p < 0.0001) and C4 fraction of complement (p < 0.0001). This last sign which is non-specific for infection has never been looked at until now in congenital toxoplasmosis but is seems to be of great importance because its sensitivity is much greater than of all the other parameters that have been used up till now (81%) and the positive predictive value is excellent (72%). On the other hand the value of a raised leucocyte count is a matter for discussion. CONCLUSION: The presence of even one abnormally raised feature in the fetal blood of these non-specific signs is enough to screen for a population which is of high risk for congenital toxoplasmosis and sufficient to change our attitude to treating the condition.

Complement C4↗
PubMed2004

[Membranoproliferative glomerulonephritis associated with autoimmune thyroiditis].

Several cases of glomerular disease have been associated to thyroid diseases. The most frequent lesion described is membranous glomerulopathy, presented as a nephrotic syndrome. Here we report a 67-year-old man who developed a nephrotic syndrome accompanied by rapid derangement of renal function shortly after the onset of a primary hypothyroidism due to autoimmune thyroiditis. High titers of circulating anti-thyroglobulin and anti-microsomal thyroid antigen antibodies were detected. Serum levels of C3 and C4 fractions of complement were markedly decreased. Renal biopsy showed a membranoproliferative glomerulonephritis with severe mesangial proliferation, a type of glomerular involvement non-described previously in the literature, in relation with thyroid diseases. Four boluses of intravenous steroids were administered, followed by oral prednisone for three months. A dramatic recovery of renal function, together with normalization of urinary sediment, proteinuria decrease and normalization of serum complement were observed. Three years later, the patient suffered from a similar event, with a positive response to steroids again. One year later, the patient had a new recurrence and was treated with mycophenolate mofetil , improving his clinical situation.

Aged↗
PubMed1987

Scleroderma and hemolytic anemia in a patient with deficiency of IgA and C4: a hitherto undescribed association.

We describe a 66-year-old women with CREST variant of scleroderma who developed autoimmune hemolytic anemia responsive to prednisone and demonstrated a deficiency of IgA and the C4 component of complement. This association of clinical, immunologic and genetic findings has not previously been reported. The literature relating to these findings is reviewed and possible mechanisms are discussed.

Aged↗
PubMedDate not supplied

[Immunochemical identification of proteins adsorbed on columns of activated charcoal during hemosorption in patients with psoriasis].

After haemosorption of patients with psoriasis eluates from columns of IGI charcoal were tested for presence of 19 main plasma proteins using monospecific antisera. Distinct selectivity of protein sorption on IGI charcoal was found due to strong adsorption of the proteins responsible for immunity (IgG, IgA, IgM, C3- and C4-components of complement) as well as of fibrinogen.

Adsorption↗
PubMed1977

Immunochemical study on serum proteins in systemic sclerosis.

Forty one patients with systemic sclerosis were studied after separation into three groups according to Barnett's classification. A multi-dimensional statistical analysis eight serum proteins revealed a difference between control patients and patients with type I and type II scleroderma. Type I scleroderma was characterised by a rise in alpha 2 macroglobulin and in the C4 fraction of complement, whilst in type II scleroderma all the proteins studied were raised, with the exception of CO complement, which was normal, and transferrin which was markedly decreased.

Blood Proteins↗
PubMed1982

Perioperative changes in complement associated with cardiopulmonary bypass.

The total haemolytic complement (CH50), the complement components C3 and C4, the complement breakdown product C3d, alternative pathway activation and transferrin, were measured before, during and after cardiopulmonary bypass. As expected, CH50 decreased after heparinization, remained low during bypass and decreased further up to 8 h after bypass. C3 and C4 decreased significantly during bypass, continued to decrease for a further 8 h after bypass (by 35% and 40% respectively) and thereafter increased gradually up to 48 h. Although the depletions observed were suggestive of complement activation, there were no demonstrable increases in C3d, and in all patients the concentration of C3d remained within the normal range. Hence it was concluded that complement depletions of this magnitude were unlikely to result from complement activation. Non-specific changes in protein concentrations during bypass, as a result of dilution, redistribution or other unidentified factors, are more probable causes of the observed reductions. The acute phase response to surgery may be a factor in the subsequent increase in C3 and C4 which is seen 24 h after bypass. As transferrin concentrations in the plasma are known to decrease during this response the observed decrease in transferrin concentration would support this view.

Adult↗
PubMed1993

A comparison of immunoglobulin G-containing high-molecular-weight complexes isolated from children with juvenile rheumatoid arthritis and congenital human immunodeficiency virus infection.

Circulating immune complexes have been described in both juvenile rheumatoid arthritis and in AIDS. We isolated high-molecular-weight complexes from plasma of children with juvenile rheumatoid arthritis and congenital human immunodeficiency virus infection by sequential gel filtration followed by affinity chromatography on protein A-Sepharose. We demonstrate that 1) mixed IgG-, IgM-, and IgA-bearing immune complexes can be found in both juvenile rheumatoid arthritis and congenital human immunodeficiency virus infection and 2) complexes isolated via affinity chromatography on protein A-Sepharose do not have detectable C4 but activate the classic complement pathway in vitro.

Adolescent↗
PubMed1987

Anticardiolipin antibodies and complement in ninety-nine women with habitual abortion.

Immunologic investigations were performed on sera from 99 women with habitual abortion (three or more consecutive miscarriages). All were considered healthy and clinical investigations had not revealed any cause for the miscarriages. Sixty-eight were considered to have primary habitual abortion whereas 31 had secondary habitual abortion. Increased anticardiolipin antibody levels were found in 42 patients. None had a primary diagnosis of systemic lupus erythematosus, but at follow-up studies one of them fulfilled the diagnostic criteria of systemic lupus erythematosus. Ten sera, all from patients with primary habitual abortion, showed high anticardiolipin antibody values (greater than or equal to 10 units) concomitant with significantly lower levels of complement factor C4 than those found in sera with moderate or normal anticardiolipin antibody levels. There was no indication of genetic defects explaining the low C4 values, which could be explained at least in part by an activation of complement by the classical pathway.

Abortion, Habitual↗
PubMedDate not supplied

The results of investigations for blocking antibody and autoantibodies help to choose between different immunological treatments for recurrent abortion.

Immunologic investigations were performed on 337 healthy women with unexplained habitual abortion. Their sera were investigated for antinuclear antibodies (ANA), antibodies against DNA, and anti-cardiolipin antibodies, and the activated partial thromboplastin time (APTT) and complement levels of their plasma were determined. Cellular reactivity and blocking antibody were studied in one-way mixed lymphocyte culture (MLC). None of the women had any signs of autoimmune disease. However, in 77 of the 337 women (22%) increased anti-cardiolipin antibody levels were found, in 19 (7%) above 10 units. Most patients with high anti-cardiolipin antibody levels had lowered values of complement factor C4. We consider the mere occurrence of anti-cardiolipin antibody in women with habitual abortion to be no absolute cause for treatment with prednisolone, and this is true even in cases with very elevated anti-cardiolipin values. Treatment with prednisolone and acetylsalicylic acid (ASA) during pregnancy should be given to only those women who have high levels of anti-cardiolipin antibodies concomitant with high APTT values, and low values of complement C4. Anti-cardiolipin antibody was also investigated during pregnancy in 136 normal pregnant women. Eleven of them (8%) were positive at any of four sampling occasions, but only one (1%) had high levels. These data differ significantly from those of the habitual aborters. Thus the development of anti-cardiolipin antibody is no normal feature of pregnancy in Swedish women and so the high frequency found among healthy Swedish women with habitual abortion remains unexplained. We have introduced an immunization programme of third party leukocyte transfusions in habitual abortion.(ABSTRACT TRUNCATED AT 250 WORDS)

Abortion, Habitual↗
PubMed1995

Serum concentrations of C4 isotypes and factor B in type I C2 deficiency suggest haplotype-dependent quantitative expression of MHC class III complement genes.

The complement protein C4 exists as two isotypes, C4A and C4B, encoded by genes in the major histocompatibility complex (MHC) class III region. The serum concentrations of C4A4 were lower than those of C4B2 in serum from 19 individuals homozygous for type I C2 deficiency (p < 0.0002). These individuals all had the S042 complotype and most of them were homozygous for the haplotype HLA-B18,S042,DR2. In 14 individuals heterozygous for the C2Q0 gene and with the C4A4, C4B2 phenotype and in 51 individuals with the C4A3, C4B1 phenotype, the isotype concentrations were equal. Factor B concentrations in the C2-deficient individuals were lower than those in individuals with the C4A3, C4B1 phenotype (p < 0.0001). The findings strongly suggest that the quantitative expression of C4 isotypes and factor B is MHC haplotype dependent. C4 null alleles cannot be accurately determined by measuring relative C4 isotype serum concentrations.

Complement C2↗