Robert W. Dorner

Cholesterol Crystals in Synovial Fluid

Excerpt The finding of crystals in synovial fluid has been the subject of much current interest following the recent description by McCarty and Hollander (1) and others (2) of uric acid crystals in...

Changes in glycosaminoglycan composition associated with maturation of regenerating rabbit tendon

Abstract Rabbit Achilles tendons were excised and regeneration allowed to proceed for various periods of time ranging from 4 days to 4 months. Regeneration tissue was then collected and analyzed for collagen solubility, hexosamine/hydroxyproline ratios, glycosaminoglycan composition and solubility profile of the CPC complexes of the glycosaminoglycans. The most extensive changes in the glycosaminoglycan composition of the regeneration tissue took place during the first 3 weeks of regeneration, and after 4 months the composition of regeneration tissue approximated that of mature tendon. Chromatographie fractions corresponding to hyaluronate, chondroitin-4-sulfate, chondroitin-6-sulfate and dermatan sulfate accounted for 56, 11, 8 and 12% of the total CPC precipitable glycosaminoglycans in 4-day regeneration tissue, while they accounted for 20, 9, 8, and 54% in 4-month regeneration tissue and for 16, 7, 9, and 60% in mature tendon. Hexosamine/hydroxyproline ratios decreased from 0.13 in 4-day tissue to 0.02 in 4-month tissue (mature tendon, 0.02).

In vitro effects of methotrexate on peripheral blood monocytes: modulation by folinic acid and S-adenosylmethionine.

The mechanism of action of low dose methotrexate in rheumatoid arthritis has not been established. It has been shown to have an anti-inflammatory effect and to inhibit neutrophil chemotaxis, but the effect on monocytes has not been widely studied. Normal donor peripheral blood monocytes were incubated with methotrexate in vitro and their superoxide production, chemotaxis, and phagocytosis subsequently assessed. Additionally, the influence of different culture media, and of folinic acid, and the methyl donor S-adenosylmethionine, and spermidine on the methotrexate mediated effects were evaluated. It was found that methotrexate in low concentrations inhibited in vitro monocyte chemotaxis and superoxide production but only after prolonged incubation. This inhibition was augmented by incubation in medium containing a low methionine concentration and was abolished by folinic acid and S-adenosylmethionine, suggesting that methotrexate may interfere with specific methylation reactions.

Hidden 19S IgM rheumatoid factor in juvenile rheumatoid arthritis.

Summary: One-hundred twenty-five serum samples from 82 patients with juvenile rheumatoid arthritis (JRA) were studied for the presence of hidden rheumatoid factor (RF) in an effort to find a better serologic marker to define JRA. Hidden 19S IgM RF was detected by means of a hemolytic assay utilizing the IgM-containing fraction of serum. The IgM fraction was obtained after acid separation of serum on a Sephadex G-200 column. Hidden 19S IgM RF was present in 68% of patients with seronegative JRA with a mean titer of 1:63. The mean titer for the polyarticular JRA group was 1:83, for the pauciarticular JRA group, it was 1:32, and for the systemic type-onset JRA patients, it was 1:32. When disease was active, the mean titer for all JRA patients was 1:108, for the active polyarticular JRA group it was 1:119, for the active pauciarticular JRA, it was 1:97, and for the active systemic JRA patients, it was 1:64. All values were significant at the P ≤ 0.001 when compared to disease and normal controls.The hemolytic assay for RF on the IgM-containing fraction of serum thus enhances the serologic capabilities of defining JRA.Speculation: These studies showing the correlation of disease activity and the presence of hidden rheumatoid factor will aid in evaluating and following disease activity in juvenile rheumatoid arthritis.

Autoantibodies in juvenile arthritis

Sera from 104 children with JA with different onset-types of disease were evaluated for 19S IgM RF by the LFT , hidden 19S IgM RF by the hemolytic assay, ANA by HEp-2 cell substrate, and levels of IC by the C1qSPA . Their relationship to active disease was determined. Classical 19S IgM RF were detected by the LFT in only seven patients. All were late-onset polyarticular females. Hidden 19S IgM RF were detected by the hemolytic assay in the separated IgM-containing fraction in 55 patients of all onset-types. Clinical activity correlated with the presence of hidden 19S IgM RF in 82% of cases. ANA, using the HEp-2 cell substrate, were found in 61 patients, the majority showing a speckled, immunofluorescent pattern. ANA were noted in all RF positive patients and in nine of 10 patients with iridocyclitis. IC were found in 39 patients, and correlation with clinical activity occurred in 54% of cases. A search for positive associations among the four parameters showed no statistically significant correlations except for the concordance of ANA positivity in all seven RF positive patients. The presence of hidden RF correlated more closely with disease activity (P less than 0.001) than did that of ANA or IC. The significance of these data and previous studies remains to be determined. We have demonstrated that in the average JA population 7% have 19S IgM RF and about 60% have hidden RF, ANA, or elevated levels of IC. The present findings of 98 of 104 patients with at least one of the abnormal immunoproteins , the association of ANA in patients with iridocyclitis or with RF positivity, of hidden RF with disease activity, and the presence of 19S IgM RF in isolated IC suggest a possible immunologic etiology for JA.

The inhibition of ciliary activity in tracheal organ cultures by sera from children with cystic fibrosis and control subjects

The cilioinhibitory effect of sera from patients with cystic fibrosis and control subjects was studied in chicken and rabbit trachel organ cultures. All sera were markedly ciliotoxic and no difference was noted between sera from cystic fibrosis patients and those of control subjects. The serum ciliotoxic factor was found to be heat labile, nondialyzable, removable by kaolin, and lost during Sephadex G-200 gel filtration.

Rapid determination of hidden rheumatoid factor

A method for the determination of hidden 19S IgM rheumatoid factor based on separation by QAE-Sephadex A-50 chromatography followed by hemolytic assay is described. Hidden rheumatoid factor titers and IgM recoveries of sera were comparable to those obtained by the conventional acid gel filtration method. The QAE method saves time, requires only 250 microliters of serum and can be performed with a minimum of specialized equipment.

Plasma and synovial fluid as solvents for monosodium urate.

In-vitro differences in monosodium urate (MSU) crystal dissolution in paired plasma and synovial fluid samples from patients with various arthritides were studied. Plasma was a significantly better solvent for MSU than synovial fluid (overall difference 6.3 mg/dl (0.37 mmol/l); significant at P less than 0.001). Attempts to correlate the solubility differentials with the principal compositional differences between the 2 fluids were only partially successful. (1) A tendency towards higher MSU solubility at higher protein levels was observed, but it was too slight to reach statistical significance. (2) Hyaluronidase treatment of synovial fluid significantly enhanced its ability to dissolve MSU (overall difference 2.2 mg/dl (0.13 mmol/l); significant at P less than 0.01) but not sufficiently to explain wholly the plasma-synovial fluid differential.

Hidden 19S IgM rheumatoid factor in adults with juvenile rheumatoid arthritis onset.

Forty-eight adult patients with juvenile rheumatoid arthritis (JRA) (onset before age 16 years) were evaluated at the age of 17 years or more for the presence of hidden 19S IgM rheumatoid factors (RF), i.e., 19S IgM RF that can be detected by the complement-dependent haemolytic assay in the IgM-containing fraction after separation of the serum by acid gel filtration. The average age of the patients was 25.3 years. The mean duration of disease was 16.5 years. Thirty-two of 48 patients (67%) showed the presence of hidden 19S IgM RF in their serum. Disease activity correlated with hidden RF titres in 62% (55/88) of the evaluations. The results indicate that patients with seronegative JRA onset continue to have significant titres of hidden 19S IgM RF in their sera into early adulthood.

Application of cetylpyridinium-complex elution methods to analysis of glycosaminoglycans of tendon

Abstract 1. 1. Glycosaminoglycans of bovine tendon, mature rabbit tendon and regenerating rabbit tendon were fractionated by the cetylpyridinium chloride (CPC) column method of Antonopoulos et al. 2. 2. The fractions were characterized by hexosamine, uronic acid, and sulfate analyses, as well as by infrared spectrophotometry and by paper chromatographic identification of the amino sugars. 3. 3. Glycosaminoglycans with the characteristics of hyaluronate, chondroitin-6-sulfate and dematan sulfate were found in all the tendon materials studied. Regenerating rabbit rendon, in addition, also contained a glycosaminoglycan with the properties of chondroitin-4-sulfate. 4. 4. With minor modifications, the CPC column method was found useful for the analysis of the glycosaminoglycan composition of tendon materials.