Search PubMed⌕ Search

Biomedical subjects

N G Sitton

Publications and source records attributed to N G Sitton.

13 recordsLinked to original sources
PubMed1988

A clinical and biochemical evaluation of etretinate in rheumatoid arthritis.

Etretinate (Tigason; Roche), which is effective in the treatment of psoriatic arthritis has immunomodulating activity in vivo. We have therefore assessed this drug in an open clinical and biochemical assessment of 24 weeks duration in rheumatoid arthritis. The treatment dose was 1.0 mg/kg/day for the first 4 weeks reducing to 0.5 mg/kg/day thereafter. There was a modest clinical improvement though this only reached statistical significance for joint circumference at 12 and 16 weeks (P less than 0.05). Biochemical improvement only reached levels of statistical significance for IgM at week 16 (P less than 0.01). Eight out of 15 patients had discontinued the drug because of side-effects by week 12 and only three out of 15 patients showed individual improvement by week 24. Some biochemical parameters (ESR) worsened. These results suggest only modest clinical efficacy and use of the drug in rheumatoid arthritis is likely to be curtailed by unacceptable side-effects. The improvement in biochemical variables that occurs when the drug is used in psoriatic arthritis does not occur in rheumatoid arthritis.

Adolescent↗
PubMed1988

A clinical and biochemical assessment of etidronate disodium in patients with active rheumatoid arthritis.

Diphosphonates reduce the rate of bone turnover. They have additional pharmacological properties improving adjuvant arthritis in rats and lowering ESR in this condition. We have evaluated etidronate disodium, a diphosphonate commonly prescribed in the United Kingdom for Paget's disease in patients with rheumatoid arthritis. Apart from an early improvement in articular index, perhaps reflecting anti-inflammatory activity, no significant change occurred in clinical variables or in laboratory indices of 'secondline' action at a dose of 5 mg/kg/day.

Adult↗
PubMed1988

Kinetic investigations into the possible cause of low serum histidine in rheumatoid arthritis.

To investigate the cause of low serum histidine in rheumatoid arthritis (RA) single oral and intravenous doses of L-histidine were administered to patients with active RA, and to an equal number of age and sex matched control subjects. In the first study 13 patients and their controls received a 100 mg kg-1 dose of L-histidine as an aqueous slurry. Significant differences were seen in body weight, predose baseline serum histidine concentration, Cmax, t1/2, and area under curve, AUC0-infinity. In a second study six patients and six controls each received a 50 mg kg-1 dose of L-histidine both orally and intravenously on two separate occasions. The patients with RA had a lower baseline serum histidine concentration, a lower volume of distribution, and a shorter plasma half life than the controls, but these differences were not statistically significant. No difference was seen in bioavailability or clearance. Low serum histidine in RA is unlikely to be due to malabsorption from the gut, uptake by abnormal gut flora, or increased metabolism.

Adult↗
PubMed1987

Serum biochemistry in rheumatoid arthritis, seronegative arthropathies, osteoarthritis, SLE and normal subjects.

Most arthritic conditions are characterized by chronic inflammation, resulting in secondary changes in serum biochemistry. In an attempt to profile different mechanisms of inflammation which might account for the clinical diversity of rheumatic diseases, we have measured C-reactive protein (CRP), plasma viscosity, serum histidine and total serum sulphydryl in 259 patients with rheumatoid arthritis (RA), 84 with ankylosing spondylitis (AS), 76 with osteoarthritis, 69 with psoriatic arthritis, 34 with systemic lupus erythematosus (SLE), 36 with Reiter's syndrome and 121 normal controls. The most extreme abnormalities were seen in rheumatoid arthritis and the least in osteoarthritis. The seronegative spondarthritides and SLE occupied a midway position, emphasizing a correlation between biochemical abnormality and severity of inflammation. A low serum histidine characterized both RA and SLE. The former was more likely to be associated with a raised CRP. Plasma viscosity was characteristically raised in psoriatic arthritis and CRP in AS.

Adult↗
PubMed1986

Serum and synovial fluid histidine: a comparison in rheumatoid arthritis and osteoarthritis.

The serum and synovial fluid (SF) histidine, sulphydryl, and protein concentrations were compared in simultaneous samples from 84 patients with rheumatoid arthritis (RA) and a control group comprising 29 patients with osteoarthritis (OA). The SF levels of histidine were higher than the serum levels in the RA patients but significantly lower than corresponding results in patients with OA (P less than 0.001). The latter had levels of serum and SF histidine which were equivalent and within the normal range. Greater quantities of protein were found in the SF of the patients with RA compared with the OA group. The serum and SF sulphydryl concentrations expressed as mumol/g protein were low but in equilibrium in patients with RA. However the SF sulphydryl (mumol/g protein) was depressed relative to serum levels in patients with OA.

Aged↗
PubMed1984

A comparison of therapies which may influence trace metals in rheumatoid arthritis.

Forty-five patients with active rheumatoid arthritis (RA) were treated with D-Penicillamine (DPA), zinc sulphate or trien for 24 weeks. Clinical and biochemical assessments were made on eight occasions during the treatment period. Results supported the view that DPA is efficacious causing both clinical and biochemical improvement, whereas zinc sulphate provided clinical benefit in some patients without improving the biochemistry, and trien was ineffective in both respects. The results indicate the need for more thorough investigations of the effect of drugs on trace metal distribution in RA.

Arthritis, Rheumatoid↗
PubMed1984

Circadian variation in biochemical assessments used to monitor rheumatoid arthritis.

Circadian variation has been demonstrated in several clinical parameters used to assess disease activity in rheumatoid arthritis, but circadian variation in modern laboratory assessments has not been studied in depth. We therefore made 2-hourly measurements of plasma viscosity, C-reactive protein, total serum sulphydryl, and serum histidine on samples obtained over a 24-hour period from 6 patients with classical or definite rheumatoid arthritis. Hourly control samples were also taken from 6 normal volunteers, 3 of whom starved from 2200 h the previous night and 3 of whom ate normally. There was no significant variation in any of these laboratory measurements between 0900 and 1800 h either in patients or controls. These findings enable us to eliminate circadian variation as a source of error when using these laboratory tests in clinical trials of slow-acting anti-rheumatoid drugs.

Adult↗
PubMed1984

C-reactive protein in the serial assessment of disease activity in rheumatoid arthritis.

C-reactive protein (CRP) levels were measured in 105 patients with rheumatoid arthritis (RA) during treatment with slow-acting anti-rheumatoid drugs D-penicillamine, alclofenac, hydroxychloroquine, gold, sulphasalazine and azathioprine. A control group treated with aspirin alone was also included. Patients were assessed clinically (pain score, articular index and summated change score) and in terms of acute-phase reactants (CRP, haptoglobin, fibrinogen, ESR and plasma viscosity) at eight separate clinic visits during the 6-month treatment period. The estimation of CRP was found to be more useful than haptoglobin, fibrinogen or ESR as an index of disease activity.

Acute-Phase Proteins↗
PubMed1983

The effect of drugs on serum histidine levels in rheumatoid arthritis.

Groups of 15 patients with active rheumatoid arthritis were treated for 24 weeks with zinc sulphate, trien, captopril, clozic in two doses or a combination of D-penicillamine and hydroxychloroquine. Serum histidine levels were monitored along with measures of disease activity including C-reactive protein, plasma viscosity, articular index, grip strength and early morning stiffness. Zinc sulphate and trien were found to be ineffective while the other drugs all showed evidence of second-line action. Serum histidine was found to improve during successful therapy. The possible cause of low serum histidine and its response to therapy is discussed.

Anti-Inflammatory Agents↗
PubMed1983

Serum biochemistry in relation to the action of azathioprine in rheumatoid arthritis.

In a long-term study we have been comparing biochemical changes in the blood of patients with classical or definite rheumatoid arthritis (RA) when groups of patients are treated for the first time with specific anti-rheumatoid drugs for a six-month period. One such group was treated for 26 weeks with azathioprine. Biochemical and clinical assessments were made at each of 10 clinic visits during the treatment period. Side-effects prevented six patients completing the study. Clinical improvement in the remaining patients was accompanied by a reduction in acute phase proteins, increases in total serum sulphydryl and serum histidine, but little or no change in immunological variables. Comparison of correlation matrices constructed between clinical and laboratory variables for azathioprine and drugs previously tested suggests that azathioprine is more effective than a control group on aspirin alone and in some ways comparable with D-penicillamine.

Aged↗
PubMedDate not supplied

A clinical and biochemical evaluation of Clozic, a novel disease modifying drug in rheumatoid arthritis.

We have compared two dose levels of Clozic, a novel agent with potential anti-rheumatoid activity, to D-penicillamine and aspirin in an observer blind randomised parallel group study of 56 patients with active rheumatoid arthritis. Eight clinical assessments and 26 laboratory assessments were performed on each patient at each visit over a six month period. Results were analysed by conventional methods and also by correlation matrices constructed between clinical and laboratory variables. Patients treated with D-penicillamine (500 mg/day) responded adequately and the control group on aspirin (up to 3.6 g of enteric coated formulation/day) performed well, though the withdrawal rate from this latter group was high, predominantly because of continued disease activity. Patients receiving Clozic (100 mg/day or 300 mg/day) improved more than patients receiving penicillamine, particularly at the higher dose. Comparison of methods of analysis validates the use of correlation matrices both for detecting anti-rheumatoid activity and for determining the optimum dose of a novel compound. This trial illustrates the problems of a study of this nature, with the powerful effect on patients of being enrolled in such a closely monitored investigation. It emphasises the greater value of biochemical changes in following disease changes.

Arthritis, Rheumatoid↗