Polydrug use at raves by a Western Australian sample.

This study aimed to quantify the patterns of drug use among a group of participants in the rave scene in Perth, Western Australia. Interviews were conducted with 83 people who had recently been to a 'rave'. The study incorporated a semi-structured qualitative interview and a structured quantitative questionnaire. This paper reports on the quantitative data collected concerning patterns of drug use in association with the last rave attended. Use of 'dance drugs' (ecstasy, amphetamines or LSD) was reported by 86.8% of the 76 respondents who had used at least one drug in association with their last rave. Nearly 80% of these had also used at least one other drug on this occasion (mean number used = 2.4). Cannabis and inhalants were the drugs most commonly combined with the 'dance drugs', several respondents used more than one 'dance drug' concurrently and 16.7% had used alcohol. It seems that a significant proportion of those using 'dance drugs' in association with raves and dance parties are mixing these drugs with other substances despite harm reduction advice to the contrary. The need for more research in this area is discussed.

Raves, drugs and experience: drug use by a sample of people who attend raves in Western Australia.

AIMS: To investigate the patterns of drug use among a sample of people in the rave scene in Perth, Western Australia and test the hypothesis that those who were less experienced in their drug use had less drug-related knowledge. DESIGN: Respondents were recruited through flyers in cafes, clothing and music stores and through snowballing. They were paid $20 for a 1 1/2 hour interview which comprised both qualitative and quantitative components. SETTING: Respondents were interviewed in cafes or restaurants, private dwellings, agencies or other public spaces. PARTICIPANTS: Eighty-three people who had been to a rave in the prior 6 months. Their mean age was 18.9 years (range 13-48) and 53% were male. MEASUREMENTS: Brief history of drug use, HIV risk behaviour, knowledge of drug-related harm and side effects experienced from drugs. FINDINGS: The group was unremarkable apart from their drug use. Ninety per cent of respondents had ever used LSD, 76% had used ecstasy and 69% had used amphetamines. Before, during or after the last rave attended 52% used cannabis and 35% had used each of amphetamines and LSD. Those who were less experienced in their drug use had less knowledge about drugs. Many respondents began using 'dance drugs' while they were still at school. CONCLUSIONS: Those with less drug-using experience may have less drug-related knowledge and may be at greater risk of harm. Strategies should be implemented which involve people in the scene, promoters, health workers and the authorities to reduce drug-related harm associated with raves and other dance events.

Neurobehavioral and magnetic resonance imaging findings in two cases of decompression sickness.

Two divers underwent neurobehavioral examinations and magnetic resonance imaging (MRI) while hospitalized during the first 2 weeks after sustaining decompression sickness (DCS). Their neurologic findings included a Brown-Séquard Syndrome consistent with spinal cord lesion, and focal deficits consistent with cerebral lesion(s). MRI revealed subcortical white matter lesions in the brains of both divers, whereas no lesion of the spinal cord was demonstrated. The patients exhibited neurobehavioral sequelae including disturbances of memory, divergent thinking, and visuospatial and motor functioning. Focal neurologic deficits resolved in both patients, and their cognitive and memory problems improved slowly. Findings in these two divers raise the possibility that cerebral insult more frequently accompanies spinal cord injury in DCS than previously thought.

Evoked potential abnormalities in children with chronic cholestasis.

To assess the effect of chronic cholestasis and vitamin E deficiency on nervous system function, we did multimodality evoked potential testing of 17 children (mean age = 47 months) who had chronic liver disease. Evoked potential testing was repeated periodically in 11 patients 1 to 33 months after the initial study. Eight children had abnormal delays of the P100 peak of the visual evoked potential, and these children each had significantly higher total serum bile acid levels than did children who had normal visual evoked potentials (p = 0.002). Bilateral brainstem auditory evoked potential abnormalities consistent with conductive hearing losses were initially present in six patients. However, persistent conductive losses were found in four patients, all of whom had arteriohepatic dysplasia. Four children had mildly abnormal somatosensory evoked potentials that were due solely to a mild peripheral neuropathy. Biochemical measures of vitamin E status were not consistently associated with either normal or abnormal visual, brainstem auditory or somatosensory evoked potentials or a combination of evoked potential abnormalities, and an abnormality of one evoked potential type was not associated with an abnormality of any other. A similar lack of relationship between evoked potential results and plasma vitamin A measurement was noted. Following marked improvement in or resolution of cholestasis in four patients, the visual evoked potential became normal, but other evoked potentials did not change. Visual evoked potential improvement was greatest in two patients who underwent orthotopic liver transplantation. This is the first report that demonstrates frequent, potentially reversible visual system abnormalities that are associated with cholestasis and cannot be attributed solely to vitamin E and/or A deficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

A cobalamin metabolic defect with homocystinuria, methylmalonic aciduria and macrocytic anemia.

We have identified a patient with methylmalonic aciduria and homocystinuria due to a defect in cobalamin metabolism of the cb1C type mutant. At the time of admission at eight months of age the patient was malnourished, hypotonic and had macrocytic anemia. Neonatal screening for hypermethioninemia associated with homocystinuria had been normal. Serum vitamin B12 was markedly increased and folate concentration was above normal, as were urinary homocystine and methylmalonic acid. The patient had abnormal brain stem auditory and visual evoked potentials. Fibroblast activity of N5-methyltetrahydrofolate: homocysteine methyltransferase was reduced to approximately 10% of concurrent controls. A course of therapy with hydroxocobalamin resulted in a 90% reduction in excretion of methylmalonic acid and normalization of the evoked potentials. These studies support the efficacy of hydroxocobalamin therapy in this disease, suggest that methylmalonic acid may be the most appropriate metabolite to monitor for therapeutic response, and in importance of electrophysiologic studies in character in objectively monitoring the response to treatment metabolic disease.

Minneapolis hip prosthesis in severe destructive lesions of the femur.

The use of the Minneapolis prosthesis was abandoned about 1955 by its originators, who had used it without acrylic for uncomplicated fractures of the femoral neck. This is the first report of its use with 'cement' fixation. It has been found to be very useful and reliable for arthroplasty of the hip in 57 patients with carcinomatous or other severe destructive lesions in the trochanteric region of the femur, being more convenient and easier to use than alternative prostheses and especially valuable in metastatic disease. Technical points relating to operative techniques are described, and postoperative Hamilton-Russell traction is recommended.

Vascular malformations of the thalamus with normal angiograms.

We describe two patients with fatal vascular malformations of the thalamus whom we thought had gliomas. They had progressive neurological impairment with subacute onset as adults. Computed tomography showed lesions of increased density with slight post-contrast enhancement; cerebral angiography was normal. Without biopsy, they received radiation therapy without benefit. Two other patients with similar radiological studies have done well with conservative treatment. We believe that these lesions have a distinctive appearance on CT, that vascular malformations can be diagnosed, even with normal cerebral angiograms, and distinguished with reasonable certainty from gliomas.

Decreased sensitivity of neurons in the basolateral amygdala to dopamine and noradrenaline iontophoresis after a kindling stimulus.

The depressant effects of iontophoretically applied dopamine and noradrenaline on glutamate-induced neuronal firing in the amygdaloid complex of cats were significantly reduced 1 and 2 h after induction of a local epileptiform afterdischarge of the kind used in kindling. Neuronal excitation by glutamate and depression by GABA were not significantly changed. This suggests that kindling is associated with a reduction of the inhibitory effects of endogenous catecholamines.

Cholinergic mechanisms in the production of focal cortical slow waves.

Microiontophoretic application of scopolamine and atropine usually induced or increased focal cortical slow waves of under 3 Hz and abolished or decreased focal fast waves of over 6 Hz whereas acetylcholine iontophoresis and electrical stimulation of the mesencephalic reticular formation had the opposite effect, suggesting that focal cortical slow waves may be due to the interruption of cholinergic input from the reticular formation.

Microiontophoretic study of the GABA receptor in the feline caudate nucleus.

The effect of microiontophoretic application of GABA and its antagonist, picrotoxin, on the firing of neurons in the feline caudate nucleus (CN) was studied. Firing was elicited by stimulation of the CN a few millimeters from the recording site. Increasing ejection currents of GABA produced a dose-dependent decrease and eventual blockade of the firing of CN neurons. The GABA current which reduced firing by 50% (ED50) was 7 nA. The Hill coefficient for the action of GABA was calculated as 1.8, indicating that a minimum of two independent subunits of the GABA receptor might need to be simultaneously occupied to activate the conductance change which produces the depressant effect. Picrotoxin blocked the action of GABA in a manner suggestive of a competitive antagonism. Dose ratios for the effects of GABA alone and of GABA during picrotoxin iontophoresis showed the dissociation constant (KD) of picrotoxin for the GABA receptor in the CN to be approximately 5 microM. Our results agree with those reported for different parts of the nervous system in various species, suggesting that the receptor which mediates the depressant effect of GABA in the CN has properties similar to striatal GABA receptors characterized in in vitro studies.