Lars-Olof Persson

Psychological factors in chronic rheumatic diseases : A review : The case of rheumatoid arthritis, current research and some problems

An overview of studies relating psychological factors to perceived well-being among Rheumatoid Arthritis (RA) patients is presented. Most attention has been devoted to the perception of control, coping and the effects of cognitive distortions. The introduction of these constructs have advanced the understanding of psychological distress among RA patients, although they explain only a smaller part. One reason could be that they give an oversimplified picture of adjustment processes in chronic and disabling diseases. This may partly be because their development are based either on studies of depression in a psychiatric sense or on how healthy subjects manage stressful events in daily life. The results therefore have limited relevance for adjustment to a life-long, chronic illness like RA. Recent research has also suggested that personality dispositions, especially neuroticism, play a substantial role in all types of subjective experiences. Finally, some issues for future research are discussed.

Mood and somatic symptoms

The relations between subjective ratings of mood and somatic symptoms were examined in four studies. Correlational analysis revealed strong relations both between and within the different aspects of mood and somatic discomforts. It was also found that the more diffuse somatic discomforts showed the highest correlations with mood. A time-series analysis also revealed that the dominating explanatory factor was from current symptom reports to current mood reports and not vice versa.

Synthesis of ATP—polyethylene glycol and ATP-dextran and their use in the purification of phosphoglycerate kinase from spinach chloroplasts using affinity partitioning

Abstract ATP was covalently bound to the polymers dextran of molecular weight 500 000 and polyethylene glycol (PEG) of molecular weight 7000–9000. The degree of substitution (the ATP: polymer molar ratio) was varied by using different concentrations of ATP in the synthesis of ATP—dextran. The partitioning of the ATP—dextran derivative in an aqueous two-phase system containing dextran and PEG was found to depend on the degree of substitution. The potential of the ATP—polymer derivatives obtained for the extraction of phosphoglycerate kinase (E.C. 2.7.2.3) from crude spinach leaf and chloroplast extract using affinity partitioning was studied and compared with the corresponding polymer derivatives of the reactive dye Procion Turquoise MX-G. Both ligands, whether bound to dextran or PEG, affected the target enzyme, phosphoglycerate kinse, but ATP showed a higher specificity. ATP bound to dextran was found to be the most powerful derivative and a rapid extraction procedure involving three main steps, precipitation with PEG, affinity partitioning with ATP bound to dextran as ligand and ion-exchange treatment, was designed. This procedure is rapid, easy to scale up and yields an enzyme preparation that is 80% pure.

A structure of self-conceptions and illness conceptions in rheumatoid arthritis (RA)

In 2 independent samples of RA patients, a large pool of self-reported illness experiences were statistically examined for content and structure of common types of self-conceptions and illness conceptions related to living with rheumatoid arthritis (RA). Multivariate analyses revealed 7 primary factors in both samples. Three constituted a positive continuum (fighting spirit, acceptance, revaluation), and 3 a negative (deprivation of life values, protest, reserved). The 7th factor (denial) was weaker and conceptually intermediate. The obtained factors contained many items similar to those in other established psychological instruments used in research on RA, but showed stronger relations to subjective well-being (mood) than any one of these. Disease indicators correlated only weakly with RA self-conceptions (RASC) and mood. The RASC factors appear to more broadly reflect different facets of positive and negative ways of individual experience of living with RA than other published instruments. They were tentatively interpreted as RA-specific expressions of dispositions towards positive and negative affect, respectively.

Rapid purification of fructose-1,6-bisphosphate aldolase from spinach chloroplasts.

A rapid procedure for the purification of fructose-1,6-bisphosphate aldolase from spinach chloroplasts is presented which involves two steps; precipitation of bulk protein with polyethylene glycol and partitioning of remaining soluble protein in aqueous two-phase systems. A 94% pure preparation is obtained within 6h with a yield of 19%. A marked difference in the partition behaviour of the aldolase activity from whole leaf tissue suggested that the procedure is less efficient when leaf extract is used as starting material.

RAPID TWO-PHASE EXTRACTION OF THE CALVIN CYCLE ENzyMES ALDOLASE AND PHOSPHOGLYCERATE KINASE

Fructose-1, 6-bisphosphate aldolase (EC 4.1.2.13) was extracted from isolated spinach chloroplasts in a procedure consisting of two steps; precipitation of bulk protein with polyethylene-glycol (PEG) with Mr = 6500-8000 and partitioning of remaining soluble protein in aqueous two-phase systems. All manipulations, including chloroplast isolation, activity measurements and protein determination, can be carried out within 6 h and the final preparation is 94% pure, on the basis of electrophoretic criteria, with a yield of 19%.

Separation of Calvin Cycle Enzymes, from Spinach Chloroplasts, by Affinity Partitioning with Triazine Dye Ligands

Partition between two aqueous phases is a technique for protein purification which is both rapid and easy to scale up. The partition of proteins between the phases can be significantly and selectively influenced by cova-lently binding various chemical groups to one of the polymers used to obtain the two phases (Johansson 1985). Most widespread is the application of specific ligands, so-called affinity partitioning. Especially the triazine dyes which are cheap and easily bound to the phase-forming polymers, dextran and polyethylene glycol, have been used. We have explored the possibility of purification of a few Calvin cycle enzymes from spinach chloro-plasts by using affinity partitioning with triazine dye ligands together with batchwise Deae-cellulose treatment.