The Generalized Self-Efficacy Scale in people with arthritis

OBJECTIVE

To examine the comprehensibility, reliability, and validity of a trait measure, the Generalized Self-Efficacy Scale (GSES), among people with arthritis. The scale is designed to measure perceived coping ability across a wide range of demanding situations.

METHODS

Four studies were conducted. Study 1 tested the comprehensibility of the GSES. Studies 2, 3, and 4 tested the reliability and validity of the modified scale. Data were collected through self-administered questionnaires. Reliability and structure of the GSES were examined using standard item analysis, internal consistency (Cronbach's alpha), test-retest reliability, and factor analyses. Concurrent and predictive validity were examined in relation to demographic, physical, psychological, and social dimensions.

RESULTS

The GSES assessed a unitary concept. Higher generalized self-efficacy was associated with greater psychological well-being, both cross-sectionally and longitudinally. The GSES was independent of age and physical health status.

CONCLUSIONS

The GSES is a reliable and valid measure for use among community-based samples of people with arthritis and may be a useful indicator of general adaptational outcomes.

Group education for people with arthritis

Arthritis is a common chronic disease causing pain and progressive disability to millions of people. The purpose of the study was to examine the effectiveness of group patient education for people with one form of arthritis, ankylosing spondylitis (AS), in terms of change in: arthritis self-efficacy; psychological well-being; physical well-being; and home exercise activities. The Self-Management Course-Ankylosing Spondylitis (SMC-AS) demonstrated positive effects on arthritis self-efficacy and psychological well-being at 6-month follow-up. Analysis of change over time in the intervention group showed improvements in depression, self-efficacy and severity at 3 weeks, with trends towards continued improvement evident at 6 months. In contrast, the positive effects on range and frequency of home exercise activities at 3 weeks were not maintained at 6 months. In conclusion, the effectiveness of short, intensive patient education courses was demonstrated. However, the need for strategies to sustain improvements in exercise behaviour need to be explored.

Health locus of control, self-help and treatment adherence in relation to ankylosing spondylitis patients

Ankylosing spondylitis (AS) is a form of arthritis characterised by an early onset and an active style of treatment involving regular exercise. Self-help groups for AS patients have developed in many countries as a means of promoting exercise treatment. The empirical section presents a comparative study of members and non-members of such groups along psychosocial dimensions including health locus of control, social support, and health behaviour. Self-help group members were distinguished by a combination of factors including a low reliance on powerful others health locus of control beliefs, greater satisfaction with available support, and increased frequency of exercise. A subsample showed improvements on physiological measurements over a 6-month period. The utility of including psychosocial variables in examination of rheumatic diseases is discussed and practical implications of these findings for health care professionals and future research are considered.

Gender, depression, and ankylosing spondylitis

Depression has been established as a common reaction to rheumatoid arthritis but has rarely been investigated among people with other forms of arthritis. The present study examined the prevalence and determinants of depressive symptoms in people with ankylosing spondylitis, focusing on gender differences and set in the context of widely held medical views concerning the psychosocial nature of ankylosing spondylitis patients. Results showed that approximately one third of the ankylosing spondylitis patients reported a high level of depressive symptoms and that women reported more depression than men. No evidence was found to support the stereotype of the "typical" ankylosing spondylitis patient as being less depressed than people with other forms of arthritis. Pain was found to be a major determinant of depression for women, but was of lesser importance for men. The implications of these findings are discussed.

Psychosocial factors and self-help in ankylosing spondylitis patients

The purpose of this research was to investigate psychological factors associated with ankylosing spondylitis (AS), focusing on possible differences between members and nonmembers of self-help groups for people with this form of chronic disease. Analysis of health locus of control beliefs along 3 dimensions: internality, powerful others and chance, showed that members of National Ankylosing Spondylitis Society (NASS) self-help groups placed significantly less reliance on "powerful others" for control of health than did nonmembers. This pattern of beliefs may be related to the nature of AS, which is incurable, progressive, unpredictable and difficult to diagnose. It may therefore appear to the patient that health care professionals have little to offer them. People who join a self-help group may also feel less reliant on medical personnel to control their health. Group members also differed from nonmembers in terms of belief in the value of exercise for AS, frequency of exercise, tendency to seek information about the disorder and perceived social support. A combination of psychosocial and medical variables discriminated between members and nonmembers at a rate of 71.9% accuracy. Results indicate that NASS self-help group members appear to comply more with exercise treatment and also receive a valuable source of social support from fellow members. This investigation demonstrates the utility of including psychosocial variables in the study of chronic disease.

Structure and methylation patterns of the gene encoding human carbonic anhydrase I

The gene (CAI) encoding human carbonic anhydrase I (CAI) has been isolated and shown to have a total length of 50 kb. Some 36 kb of this consists of a large intron separating the erythroid-specific promoter from the coding region. A small (54 bp) noncoding exon from within this intron is occasionally found in transcripts. Two different polyadenylation sites have been found, the most distal of which is the most commonly used. Methylation levels near the promoter differ widely in cell lines. In CAI-expressing cells, a region of DNA near the promoter is demethylated in a generally highly methylated background. Surprisingly, non-CAI-expressing cell lines show much lower levels of methylation.

Expression of the human carbonic anhydrase I gene is activated late in fetal erythroid development and regulated by stage-specific trans-acting factors

Using flow cytometric analysis of red cells from different stages of ontogeny with anti-CAI antibody, it was shown that the human carbonic anhydrase I (HCAI) gene product appears in a developmental stage-specific manner. Virtually no CAI protein was detectable in fetal red cells prior to birth. However, at about the time of normal delivery (40 weeks gestation) CAI production is switched on. The proportion of cells containing CAI reaches adult levels during the second half of the first year of life. Northern analysis suggests that the appearance of CAI protein results directly from the activation of the gene and the production of new mRNA. A transient heterokaryon system was set up by fusing the erythroleukaemic cell lines MEL C88 (a mouse cell line in which CAI is expressed) and K562 SAI (a human cell line with an embryonic/fetal phenotype, not expressing CAI). SP6 RNAase mapping of RNA from the fused cells showed activation of the human CAI gene. This shows the developmental stage-specific expression of HCAI to be regulated by trans-acting factors.

Regional localization of carbonic anhydrase genes CA1 and CA3 on human chromosome 8

The human carbonic anhydrase isozymes represent a family of homologous proteins which are important in respiratory function, fluid secretion, and maintenance of cellular acid-base homeostasis. Using somatic cell genetic techniques we have mapped two of the CA genes (CA1 and CA3) to human chromosome 8. In situ hybridization data demonstrates that both CA1 and CA3 map to the same region (q13-q22) of chromosome 8.

Assignment of the gene determining human carbonic anhydrase, CAI, to chromosome 8

A cDNA clone complementary to the mRNA encoding the rabbit erythrocyte specific carbonic anhydrase, CAI, has been used as probe for human CAI sequences in the analysis of DNA from panels of rodent/human somatic cell hybrids. The presence of the human CAI gene in all hybrids correlates with the presence of chromosome 8. Together with published mapping data, this assignment indicates that three CA loci are situated on chromosome 8.

Cloned cDNA for rabbit erythrocyte carbonic anhydrase I: A novel erythrocyte-specific probe to study development in erythroid tissues

Present understanding of gene expression in erythropoietic tissues is derived solely from studies of the globin genes. Of the three distinct carbonic anhydrase (carbonate dehydratase; carbonate hydro-lyase, EC 4.2.1.1) isozymes, carbonic anhydrase I is erythrocyte-specific and, in humans, is under developmental control. The appearance of carbonic anhydrase I in the erythrocyte late in fetal life follows closely the gamma- to beta-globin switch. In order to study the expression of this erythrocyte-specific nonglobin protein, we set out to isolate a cloned carbonic anhydrase I cDNA. A mixture of 17-base-long synthetic oligonucleotides was used as an in situ hybridization probe to screen a rabbit reticulocyte cDNA library. Two clones were isolated, and the complete nucleotide sequence of the clone with the largest insert was determined and shown to code for carbonic anhydrase I. This clone, designated pRCAI, is near full length and has provided the 40% of the amino acid sequence of rabbit carbonic anhydrase I, which was not known hitherto. The deduced primary structure has revealed potentially significant changes in the vicinity of the active site of the rabbit carbonic anhydrase I when compared with carbonic anhydrase I and II sequences from other species.

Evidence for the re-establishment of a heterogeneity in radiosensitivity among spermatogonial stem cells repopulating the mouse testis following depletion by X-rays

Earlier studies have shown that the spermatogonial stem cells of the mouse testis recovering from previous radiation or chemical mutagen exposure give subnormal yields of genetic damage with subsequent X-irradiation. This response has been investigated further: (a) with a high, 9-Gy X-ray dose given 4, 12 or 21 days after a 1-Gy conditioning dose (Expt. 1), and (b) with a 1 + 7-Gy, 24-h fractionation regime given 4 or 14 days after a 1-Gy conditioning dose (Expt. 2). In Expt. 1 the 1 + 9-Gy, 4-day interval regime gave a very low response, lower than obtained previously with an equivalent 1 + 5-Gy treatment. This suggests that a heterogeneity in radiosensitivity, such as exists in unirradiated stem cell populations and absent 24-48 h after radiation depletion, is quickly re-established among the stem cells repopulating the testis. By contrast, the 1 + 7-Gy, 24-h fractionation when given 4 days after the 1-Gy conditioning dose (Expt. 2) gave a very high yield of genetic damage, almost as high as that given by the fractionated (1 + 7 Gy) dose applied to previously unirradiated stem cells. This suggests that the newly established heterogeneity is removed by the second 1-Gy conditioning dose. With longer intervals between treatments, genetic yields consistent with additivity were obtained in Expt. 1; less clear results were obtained Expt. 2. Comparison with earlier data generally suggested that the duration of the repopulating period is dose-dependent. In a third experiment evidence was obtained that genetic damage induced by X-irradiation can be reduced by a subsequent treatment with triethylenemelamine (TEM) during the repopulating phase. This confirmed an earlier finding. Such an interaction could not be demonstrated with two X-ray treatments. An explanation for the X-ray/TEM interaction is offered.