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W Sequeira

Publications and source records attributed to W Sequeira.

27 records · Page 2Linked to original sources
PubMed1984

Detection of alpha 2-macroglobulin-associated proteases in the plasma of patients with rheumatoid arthritis.

In previous work a polyclonal B cell activator has been detected in the serum of patients with rheumatoid arthritis (RA). This activator is associated with alpha 2-macroglobulin (alpha 2M) and its activity is blocked by low-Mr trypsin inhibitors, which suggests that it may be a protease-alpha 2M complex. Here we determined the possibility of developing a routine clinical chemistry test for detection of this complex in patients' blood. We measured with chromogenic substrates the total proteolytic activity of citrated plasma and of the alpha 2M immunoabsorbed from plasma. Low-Mr substrates containing Arg were degraded much better by plasma from RA patients than by plasma from patients with other arthritides. Low-Mr substrates containing Leu, Lys, or Gly or the large-Mr substrate Azocoll were not degraded by RA patients' plasma. alpha 2M from RA patients' plasma attached to a solid-phase immunoabsorbent degraded an Arg-containing tripeptide much better than did the alpha 2M from normal donors, from patients with systemic lupus erythematosus, or from those with joint inflammation of other, "non-autoimmune" origin. Although the enzyme associated with alpha 2M in the plasma from RA patients appeared to be similar to trypsin, the differences in optimal pH, cation concentration, degradation of Lys-containing substrates, and biological activity suggest otherwise. We speculate that the alpha 2M-protease complexes are generated in the immune system and contribute to the inflammatory and autoimmune phenomena in RA.

Arthritis, Rheumatoid↗
PubMed1984

A significant increase of HLA-DR3 and DR2 in systemic lupus erythematosus among blacks.

We found a highly significant increase in the incidence of HLA-DR3 and DR2 antigens in black patients with systemic lupus erythematosus (SLE). HLA-DR3 was found in 62% of patients and 20% of controls (p less than 0.0001), and DR2 in 41% of patients and 18% of controls (p less than 0.001). The relative risk (RR), conferred by DR3 was 6.41, and that by DR2 was 3.03. Further, 84% of the patients had DR3 and/or DR2; the combined RR for SLE with these antigens was 9.0. A significant proportion of the patients (57%) developed lymphocytotoxic antibodies; of these, 19% had HLA specific antibodies.

ABO Blood-Group System↗
PubMed1982

Pyogenic infections of the pubic symphysis.

Four cases of Pseudomonas aeruginosa infection of the pubic symphysis occurred in intravenous abusers of pentazocine hydrochloride and pyribenzamine. Symptoms included suprapubic pain when walking, bilateral inguinal pain, and pain caused by hip flexion and rotation. Cultures of material taken by joint aspiration and open biopsy yielded P. aeruginosa in three patients and P. aeruginosa, P. maltophilia, and Corynebacterium in the fourth. All four responded to antibiotic treatment and open debridement but were lost to follow-up. Recent reports of P. aeruginosa arthritis in intravenous drug abusers are discussed. The concept of infective synchondritis as a distinct entity is suggested.

Adult↗
PubMedDate not supplied

The neuropathic joint.

Neuropathic arthritis is a destructive arthropathy frequently associated with loss of proprioception. A third of patients, however, may have no demonstrable neurological deficit. Patients with diabetes, syphilis, syringomyelia and other neuropathies are particularly prone to developing this joint disease. The diagnosis of Charcot's joints should be considered in anyone who develops what appears to be a severe osteoarthritis or a transverse fracture of the tibia or fibula after minor trauma. Scoliosis with particularly destructive changes on radiography should prompt a search for syringomyelia or syphilis. The most common radiographic abnormalities are those of distension in 3D (Dislocation, Destruction and Degeneration). An atrophic form with resorption of the proximal humerus, most frequently described in syringomyelia, has been observed in diabetes. Loss of the distal end of the clavicle has not been described before in the neuropathies. These changes coupled with speckled calcification or shards of bone in the periarticular soft tissue confirm the diagnosis. Infection and CPPD crystal disease can be difficult to exclude. The joint fluid may be inflammatory and infection may be a complication. Treatment includes anti-inflammatories and splinting. Indications for surgery are limited.

Arthritis↗