Cortical and nigral deafferentation and striatal cholinergic markers in the rat dorsal striatum: different effects on the expression of mRNAs encoding choline acetyltransferase and muscarinic m1 and m4 receptors.

The regulation of the striatal m1 and m4 muscarinic receptor mRNA as well as the choline acetyltransferase (ChAT) mRNA expression by nigral dopaminergic and cortical glutamatergic afferent fibres was investigated using quantitative in situ hybridization histochemistry. The effects induced by a unilateral lesion of the medial forebrain bundle and a bilateral lesion of the sensorimotor (SM) cortex were analysed in the dorsal striatum 3 weeks after the lesions. Dopaminergic denervation of the striatum resulted in a marked decrease in the levels of m4 mRNA throughout the striatum, while the levels of muscarinic m1 mRNA and ChAT mRNA in cholinergic neurons were unaffected by the lesion. In contrast, following bilateral cortical ablation, the levels of the muscarinic m1 mRNA were significantly increased in the striatal projection area of the SM cortex, whereas the expression of m4 mRNA remained unchanged. Single cholinergic cell analysis by computer-assisted grain counting revealed a decreased labelling for ChAT mRNA per neuron following cortical ablation. However, in contrast to the topographical m1 mRNA changes, the decreased ChAT mRNA expression was evenly distributed within the striatum, suggesting an indirect cortical control upon striatal cholinergic interneurons. Altogether, these data suggest that dopaminergic nigral and glutamatergic cortical afferents modulate differentially cholinergic markers, at the pre- and post-synaptic levels. Beside the fact that nigral and cortical inputs exert an opposite control on cholinergic neurotransmission, our study further shows that this control involved different muscarinic receptor subtypes: the m4 and m1 receptors, respectively.

Interprofessional contacts between chiropractors and other health-care professionals in Sweden as seen from a chiropractic perspective.

OBJECTIVE: To investigate the type and extent of interprofessional contacts between chiropractors and members of the conventional Swedish health-care system and to study the possible barriers to effective cooperation between these groups. DESIGN: Surveys through self-administered questionnaires and a structured telephone interview. PARTICIPANTS: Twenty consecutive patients of 31 chiropractors (n = 616) participated in the questionnaire survey, and 15 randomly selected chiropractors participated in the telephone interview. SETTING: Chiropractic practices in Stockholm, Sweden. MAIN OUTCOME MEASURES: Information was sought on the type and number of interprofessional contacts and on barriers to free and effective communication. RESULTS: Eighteen percent of patients were recommended to chiropractic care by some other health-care practitioner. Only 1% of the participating patients were referred for chiropractic care with a written request. Almost all chiropractors (87%) could provide a list of the last three health-care professionals with whom they had contact. The median number of interprofessional contacts per month was estimated by the chiropractors to be 10. Legal recognition of chiropractors and the inclusion of these in the County Council reimbursement program were thought to have improved the image of chiropractic. Considerable barriers to cooperation were stated to exist still. CONCLUSION: Successful integration of chiropractors into the Swedish health-care system requires an overall policy plan and practical guidelines of cooperation.

Quality assurance in chiropractic practice: a comparison of two study methods.

OBJECTIVES: A comparison was made of two methods of data collection used in a quality-assurance study to determine whether the study samples were comparable and self-reported satisfaction similarly. We also investigated whether patients who dropped out of treatment early were more dissatisfied than those who remained for more treatments. STUDY DESIGN: A comparison was made of data collected through self-administered, structured questionnaires in the two studies. Participants were invited consecutively by chiropractors in study 1; chiropractic patients, selected randomly from a reimbursement register, received a postal questionnaire in study 2. PARTICIPANTS: Study 1 aimed for a maximum of 20 patients for each of 31 chiropractors included under a reimbursement scheme in the county of Stockholm, Sweden. Six hundred and sixteen patients entered the study, and 83% participated in a survey conducted at their third visit. Three hundred patients were invited to respond to the postal questionnaire at least 1 month after they received chiropractic care; the response rate was 77%. MAIN OUTCOME MEASURES: Sociodemographic factors, area of complaint, sick-leave, perceived improvement, unpleasant side-effects and overall satisfaction with care. RESULTS: There were no differences noted between the two study groups, and patients who received fewer than three treatments were no less satisfied than those who received more. Additional analyses indicate that factors other than dissatisfaction influence whether patients remain in therapy for fewer than three visits. CONCLUSION: Quality-assurance studies conducted in the chiropractor's practice, using consecutive sampling and anonymous questionnaires, seem to give results that are similar to the more complex and costly method of obtaining randomly selected study subjects from a central source and collecting the information through anonymous postal surveys.

Muramyl peptides and the functions of sleep.

Muramyl peptides (MPs) are bacterially derived sleep factors which stimulate slow wave sleep. In the neonate, MPs are capable of inducing quiet sleep and suppressing active sleep. Given that active sleep is thought to be important for brain development during this period, the possibility that changes in the availability of MPs in the neonate may affect brain development was examined. Rat pups were given muramyl dipeptide (MDP) twice daily for the first 14 days post partum. It was hypothesised that MDP would stimulate quiet sleep at the expense of active sleep as has been shown in the young rabbit. There was no effect on neonatal levels of quiet sleep or active sleep. There was, however, a variety of effects, apparently unrelated to the sleep functions of MDP. These effects were changes in adult learning, serotonin metabolism and brain anatomy. The function of sleep in the mediation of the sleep-independent effects of MPs was examined, in particular the opposite effects of MDP on host immunity depending on the sleepiness of the host. In this light sleep does indeed serve to mediate the effects of MPs and it is speculated that many of the effects observed here may change in response to sleep levels in individuals. The notion that autonomic signalling between brain and spleen is more efficient during sleep is presented as an example of a function of sleep that may modulate the immunological effects of MPs.

Clinical competence of interns. Programme Evaluation Committee (PEC).

A clinical supervisors rating form addressing 13 competencies was used to assess the clinical competence of graduates one year after qualification in New South Wales (NSW), Australia. Data from 485 interns (97.2%) showed that graduates from the problem-based medical school were rated significantly better than their peers with respect to their interpersonal relationships, 'reliability' and 'self-directed learning'. Interns from one of the two traditional NSW medical schools had significantly higher ratings on 'teaching', 'diagnostic skills' and 'understanding of basic mechanisms'. Graduates from international medical schools performed worse than their peers on all competencies. These results were adjusted for age and gender. Additionally, women graduates and younger interns tended to have better ratings. Junior doctors have differing educational and other background experiences and their performance should be monitored.