Comparison of gastroduodenal, renal and abdominal fat biopsies for diagnosing amyloidosis in rheumatoid arthritis.

The aim of the study was to determine the frequency of amyloidosis detected by gastroduodenal biopsy in rheumatoid arthritis (RA) patients, and to investigate correlations between the results of gastroduodenal biopsy and abdominal fat and renal biopsies. A total of consecutive 1006 RA patients underwent gastroduodenal biopsy. The 71 patients who tested positive for gastrointestinal (GI) amyloidosis were asked to undergo renal and abdominal fat biopsies, and 21 did so. Renal biopsies were also performed on 12 patients with no amyloidosis but indicators of drug-induced renal damage, and abdominal fat biopsies were performed on 50 RA patients with no indication of amyloidosis. The prevalence of GI amyloidosis was 7.1%. Urinary abnormalities and GI symptoms were common in GI amyloidisis, and inflammatory markers were elevated. Sixty-one (86%) had either depressed creatinine clearance or urinary symptoms. Nineteen of the 21 patients (91%) with GI amyloidosis who underwent renal biopsies also had renal amyloid deposits. Eleven of the 21 (52%) had amyloidosis on abdominal fat biopsy. None of the 12 patients without GI amyloidosis had renal amyloidosis on renal biopsy, and none of the 50 patients without GI amyloidosis had amyloidosis on abdominal fat biopsy. Gastroduodenal biopsy reveals a high prevalence of amyloidosis in RA patients. Amyloidosis is often associated with signs of renal impairment. Results of GI biopsy are highly correlated with those of renal biopsy, but the results of fat biopsy are not. We recommend GI biopsy for RA patients for the screening of systemic amyloidosis.

Interleukin-2 levels are elevated in the bone marrow serum of patients with mutilans-type rheumatoid arthritis.

In order to investigate the pathogenesis of mutilans-type rheumatoid arthritis (RA), we measured cytokine levels in the bone marrow serum of patients with RA. We studied 35 patients with non-mutilans RA, 19 with mutilans RA, and 20 patients with osteoarthritis (OA) undergoing joint surgery. At the time of surgery, iliac bone marrow and peripheral blood were sampled from all 74 patients and cytokine levels measured. The serum levels of five cytokines (IL-1beta, IL-2, IL-3, IL-6 and GM-CSF) were measured by ELISA. Haematologic and inflammatory factors were also measured. Levels of IL-2, IL-6 and GM-CSF in bone marrow serum were significantly higher in all RA patients than in those with OA. Mean (+/-SD) IL-2 levels were significantly higher in patients with mutilans-type RA (309.8+/-686.3 pg/ml) than in patients with other types of RA (66.5+/-173.1 pg/ml; P<0.01). IL-2 was detected significantly more often in patients with mutilans-type RA than in patients with other types of RA (P < 0.01). Inflammatory factors were higher in all RA groups than in OA patients. However, the haematologic and immunologic variables were no different between mutilans RA and other types of RA. No correlations were observed between IL-1beta, IL-2, IL-3, IL-6 and GM-CSF levels and these laboratory variables. In patients with mutilans-type RA, IL-2 levels in the bone marrow serum were significantly higher than in patients with other types of RA or with OA. This elevation does not appear to be related to systemic inflammation, as there was no correlation with other inflammatory factors.

Fourier transform infrared spectrum of the radical cation of beta-carotene photoinduced in photosystem II.

A Fourier-transform infrared (FTIR) spectrum of the radical cation of beta-carotene photoinduced in photosystem II (PSII) membranes was obtained at 80K under oxidizing conditions, by utilizing the light-induced FTIR difference technique. Formation of the beta-carotene cation was monitored with the electronic absorption band at 993 nm. An FTIR spectrum of a chemically-generated beta-carotene cation in chloroform was also measured and compared with the spectrum of PSII. Since the FTIR bands of carotenoid cation have characteristic features with strong intensities, they can be useful markers in studying the reaction of carotenoid in PSII.