Biomedical subjects

A Gabriel Júnior

Publications and source records attributed to A Gabriel Júnior.

15 recordsLinked to original sources

PubMed1993

Wa idiotype in seropositive rheumatoid arthritis.

Antibodies against cross-reactive idiotypes (CRIs) may prove useful as phenotypic tracers of immunoglobulin variable region genes (VH or VL). CRIs of human rheumatoid factors (RFs) seem to be useful in the elucidation of the incidence and structural characteristics of the latter. Anti-Wa CRI antibodies were produced and an enzyme immunoassay was developed to test polyclonal RFs isolated from sera of 20 rheumatoid arthritis (RA) patients, 7 males and 13 females, aged 17 to 74 years. Seventeen patients had clinically active disease and three were in remission. Disease duration ranged from 1 to 25 years and RF titers ranged from 1:160 to 1:640. The immunoassay could detect as little as 8 ng of a monoclonal purified WaRF and positive results were found in 30% of patient sera. Therefore, we may conclude that at least part of the RFs seen in RA patients derives from germ line genes.

Adolescent↗

PubMed1991

A simple radial immunohemolysis assay for the measurement of functional complement C2 activity.

1. This study describes a simple radial immunohemolysis method for determining the hemolytic activity of the second component of complement (C2) in human serum. The assay is based on the recovery of hemolytic activity of normal serum which has been pretreated to inactivate endogenous C2 and then mixed with test serum containing an unknown amount of C2. 2. The pretreated serum, designated R2 reagent, is obtained by heating normal human sera under carefully standardized conditions of temperature, time, volume and type of test tube. 3. R2 reagent is incorporated into agarose together with hemolysin-sensitized erythrocytes, and spread on a plate. The test serum is placed in wells cut in the agarose and, after appropriate incubation, the diameters of the hemolytic areas are measured. The area of hemolysis is directly proportional to the logarithm of the serum concentration. As a standard for C2 functional activity, dilutions of a pool of normal sera are tested on the same plate. 4. The method is specific for C2 and can detect as little as 20% of the C2 in normal serum (about 6 micrograms C2 protein/ml). The error in reproducibility is about 3% of the mean. In normal serum, the lower confidence limit of the distribution of the C2 values (based on a sample of 80 individuals) corresponded to 70% of undiluted serum. 5. This method is suitable for use in clinical laboratories since it is simple, rapid, quantitative and inexpensive, and does not require special equipment.

Adolescent↗

PubMed1990

Panoramic nailfold capillaroscopy: a new reading method and normal range.

Current interpretation of nailfold capillaroscopy is largely based on qualitative and subjective parameters. These parameters make the accurate assessment of the extent of the nailfold microangiopathy difficult. The authors present a comprehensive method in which several quantitative or semiquantitative parameters are used to assess the main microangiopathic features, such as microhemorrhage, plexus visibility, devascularization, and morphologic anomalies of the end row loops. The method is checked for reproducibility and applied to a sample of 800 healthy people to establish the normal range. The influences of extrinsic variables, such as gender, ethnicity, age, and local nailfold conditions are also included.

Adolescent↗

PubMedDate not supplied

Protein-losing enteropathy in systemic lupus erythematosus.

We describe a 23-year old Brazilian woman with systemic lupus erythematosus and protein-losing enteropathy. Small intestinal biopsy revealed lymphangiectasia. Protein-losing enteropathy responded to corticosteroid therapy and should be suspected in cases of systemic lupus erythematosus with hypoalbuminemia without proteinuria and liver failure. A review of the English literature is presented with comments on pathogenesis.

Adult↗

PubMedDate not supplied