Steroid 21-hydroxylase expression in cultured rat astrocytes

Over the past decade or so it has become widely recognised that the brain is a significant steroidogenic organ. Many publications have highlighted the ability of the brain to synthesise and interconvert a large number of steroid products including cholesterol, progesterone and testosterone. In this study, in vitro experiments were performed to determine if 21-hydroxylation of steroids is undertaken by rat brain astrocytes in culture. This is a common reaction that occurs in the adrenal gland and other organs in mammals, catalysing the conversion of pregn-4-ene-3,20-dione (progesterone) to 21-hydroxypregn-4-ene-3,20-dione (deoxycorticosterone).

Previous reports have indicated that 21-hydroxylation occurs within the rat brain, however, the precise identity of the cells expressing 21-hydroxylase has not yet been determined. Several metabolites, such as 5α-pregnan-3α-ol-20-one (tetrahydroprogesterone) and 3α,21-dihydroxy-5-pregnan-20-one (tetrahydrodeoxycorticosterone) were of particular interest because of their modulatory role in neuronal function, such as their agonist activity at γ-aminobutyric acid (GABA_A) receptors.

Evidence was obtained for the expression of peripheral 21-hydroxylase enzyme (P450c21) in cultured rat brain astrocytes by a combination of mass spectroscopy and molecular biology techniques. This is a significant finding as expression of 21-hydroxylase within astrocytes may be indicative of a wider role for these cells in modulating neuronal behaviour.

Genetic and environmental influences on variation in balance performance among female twin pairs aged 21-82 years

Genetic and environmental influences on variation in balance performance were measured in 93 monozygous and 83 dizygous female twin pairs aged 21–82 years (mean age, 50.5 years) in Melbourne, Australia, between 1999 and 2003. The authors administered clinical (Lord's Balance Test and Step Test) and laboratory tests of static and dynamic balance from the Chattecx Balance System with and without distractor tasks. The authors conducted factor analysis and estimated genetic and environmental variance components and heritability (defined as additive genetic variance as a proportion of all variance, after adjustment for age) using a multivariate normal model with the statistical package FISHER. Three factors were identified and adjusted for age. Heritability was 46% (standard error (SE), 9) for the "sensory balance tests" factor and 30% (SE, 9) for the "static and dynamic perturbations" factor. For both factors, the remaining variance was attributed to unique environmental effects. There was no evidence that genetic factors influenced variation in the "dynamic weight shift tests" factor, with environmental effects shared by twins accounting for 38% (SE, 7) of variance. Neither genetic nor environmental proportions of variance differed significantly between twin subgroups by age (≤50/>50 years). An age-related decline in performance measures was found across the whole sample. These results imply that balance impairments may have a heritable element.

Psychometric properties of the DASS-21 in Malaysia

The use of scales to measure constructs in populations or contexts other than that in which they were normed is highly controversial. Despite this, the use of scales without reference to 'local' norms is still widespread. In this study we examine the reliability, factor structure and convergent validity of the short form of the Depression, Anxiety and Stress Scales (DASS-21), in a convenience sample of 191 people recruited from the general population in Malaysia. Confirmatory factor analysis suggests that a three factor solution provides an acceptable fit, however these three factors are highly correlated. Scores on the depression, anxiety, and stress scales of the DASS-21 correlate with the BDI-II at only moderate levels, suggesting that convergent validity of the depression scale is weak, and that there are not differential relationships between the BDI-II and the three DASS scales. Issues related to the possible role of cultural factors in response patterns, and the need for a greater understanding of the manifestations of psychological distress and how it relates the DASS-21 scales in Malaysia are discussed.

The validity of the 21-item version of the depression anxiety stress scales as a routine outcome measure

Objective: This study aimed to test the validity of the 21-item Depression Anxiety Stress Scales (DASS-21) as a routine clinical outcome measure in the private in-patient setting. We hypothesized that it would be a suitable routine outcome instrument in this setting.

Method: All in-patients treated at a private psychiatric hospital over a period of 24 months were included in the study. Data were collected on demographics, service utilization, diagnosis and a set of four routine measures both at admission and discharge. These measures consisted of the Clinical Global Impressions (CGI) scales, Health of the Nation Outcome Scales (HoNOS), the Mental Health Questionnaire (MHQ-14) and DASS-21. The results of these measures were compared.

Results: Of 786 admissions in total, the number of fully completed (ie paired admission and discharge) data sets for the DASS-21 depression, anxiety and stress subscales were 337, 328 and 347, respectively. All subscales showed statistically significant reductions in mean scores from admission to discharge (P < 0.001) and were significantly correlated with all MHQ-14 subscales and significantly related to CGI scale categories. The total DASS-21 and total HoNOS scores were also significantly correlated.

Conclusions: The findings from the present study support the validity of DASS-21 as a routine clinical outcome measure in the private in-patient setting.

I wish I was 21 now beyond doping in the Australian peloton

An investigation into the reasons for doping among professional athletes (cyclists) and attitudes towards and assessments of current attempts and form of legislation and regulation of doping, inlcuding prospects for reform, and types of reform required.