Asthma epidemiology: has the crisis passed?

PURPOSE OF REVIEW: Asthma is a difficult, resource-intensive disease that can result in symptoms, hospitalization and, in rare cases, death. In the past few decades, there has been an abundance of evidence showing the prevalence of asthma to be increasing in certain regions. However, reports have recently emerged suggesting that asthma prevalence has stabilized. This has led to debate among researchers whether increases in asthma prevalence have come to an end. We reviewed recent literature in search of answers to the ongoing debate on whether the asthma crisis is over. RECENT FINDINGS: In contrast with past reports, several recent studies have reported a stabilization of asthma prevalence. However, based on repeated cross-sectional studies, findings regarding the stabilization of asthma prevalence have been inconsistent, especially when considering the heterogeneity of the disease, which can result in a variety of patterns concerning asthma diagnosis, symptoms, and allergic sensitization. Temporal trends considering physician visits, hospitalizations, and mortality have been more consistent, with stabilizing and decreasing patterns of asthma burden in recent years. SUMMARY: Because reasons for the original increases in asthma prevalence remain unclear, an explanation for the apparent stabilization of asthma prevalence reported in some studies also remains elusive. This is compounded by the difficulty in defining asthma accurately in population studies and inconsistencies in the results of prevalence estimation among repeated cross-sectional studies. Efforts should be made to continue monitoring asthma prevalence and to begin monitoring asthma prevalence in regions where environmental and social changes are occurring.     

Prolactin responses to neuroleptics in normal and schizophrenic subjects.

The prolactin response to neuroleptics can serve as an index of dopamine blockade in humans. Plasma prolactin increments to single doses of chlorpromazine, and prolactin decrements to single doses of levodopa, were similar in normal and schizophrenic subjects. Antischizophrenic drugs of all chemical classes stimulated prolactin release,while chemically related drugs and other psychotropic agents ineffective in schizophrenia did not. The prolactin response to neuroleptic therapy occurred in all patients, and tolerance did not develop. Within subjects, prolactin responses were graded according to neuroleptic dose, but the upper limit of sensitivity of the response curve was achieved at doses below the therapeutic range. Relative prolactin-stimulating potency in humans of chlorpromazine, thioridazine, trifluoperazine, butaperazine, and haloperidol correlated well with their relative clinical potencies.     

Diurnal cortisol responses to dextroamphetamine in normal subjects

(1) Dextroamphetamine, in doses of 0.1 and 0.15 mg/kg, was administered intravenously morning and evening to normal young men and postmenopausal women, and plasma cortisol responses were assessed. (2) There were no differences in cortisol responses between the young men and older women at either dose. (3) The higher dose elicited a significant and reliable acute cortisol release, while the lower dose did not. (4) In the evening, 0.15 mg/kg amphetamine elicited a larger cortisol increase from baseline than the same dose in the morning. (5) Within morning or evening periods, baseline cortisol values were not significantly correlated with magnitude of cortisol responses, although trends for inverse correlations were observed. (6) It is suggested that these normal diurnal differences in the acute cortisol response to amphetamine may be related to a corresponding rhythm in the responsitivity to amphetamine of neuroendocrine neurotransmitters. (7) The previously reported abnormal cortisol response to amphetamine in a group of endogenous depressives probably is not primarily related to variables of age, sex or baseline cortisol level.     

Preparation of primary monolayer cultures of adult rat hepatocytes

Summary We describe in detail the technique of hepatocyte isolation and establishment of primary cell cultures of adult rat hepatocytes. These cultures contain hormonally responsive hepatocytes that retain many adult characteristics under completely serum-free conditions. The cells retain a normal morphology and do not exhibit fetal characteristics during a 4 d culture period.     

The effects of alpha/theta neurofeedback on personality and mood

Alpha/theta neurofeedback has been shown to be successful both in treating addictions and in enhancing artistry in music students. How its effects are mediated are not yet clear. The present study aimed to test the hypothesis that alpha/theta neurofeedback works inter alia by normalising extreme personality and raising feelings of well being. 12 participants with high scores for Withdrawal (as measured by the PSQ) were given either alpha/theta neurofeedback or mock feedback and their personality and mood were assessed. Withdrawal scores on the PSQ-80 were not found to change in either group but significant effects were found for the Profile Of Mood States (POMS), with real feedback producing higher overall scores than mock feedback (P = 0.056). Real feedback caused participants to feel significantly more energetic (P < 0.01) than did mock feedback. Sessions of real feedback made participants feel more composed (P < 0.01), agreeable (P < 0.01), elevated (P < 0.01) and confident (P < 0.05), whilst sessions of mock feedback made participants feel more tired (P < 0.05), yet composed (P < 0.01). These findings suggest that, whilst 9 sessions of alpha/theta neurofeedback was insufficient to change personality, improvements in mood may provide a partial explanation for the efficacy of alpha/theta neurofeedback.