Reciprocal thalamocortical connectivity of the medial pulvinar: a depth stimulation and evoked potential study in human brain.

The thalamic medial pulvinar nucleus (PuM) is fully developed only in primates and reaches its greatest extent in humans. To assess the reciprocal functional connectivity between PuM and cortex, we studied intracerebral-evoked responses obtained after PuM and cortical electrical stimulation in 7 epileptic patients undergoing depth electroencephalographic recordings. Cortical-evoked potentials (CEPs) to PuM stimulation were recorded from all explored cortical regions, except striate cortex, anterior cingulated, and postcentral gyrus. Percentages of cortical contacts pairs responding to PuM stimulation (CEPs response rate) ranged from 80% in temporal neocortex, temporoparietal (TP) junction, insula, and frontoparietal opercular cortex to 34% in mesial temporal regions. Reciprocally, PuM-evoked potentials (PEPs) response rates were 14% after cortical stimulation in insula and frontoparietal opercular cortex, 67% in the TP junction, 76% in temporal neocortex, and 80% in mesial temporal regions. Overall, our study of functional PuM connectivity in the human brain converges with most of the data from anatomical studies in monkeys, except for a strong amygdalohippocampal functional projection to PuM and an unexpected imbalance between some of the reciprocal pathways explored. This functional quantitative approach helps to clarify the functional role of PuM as well as its implication in temporal lobe epileptic seizures.

[11C]-Methionine PET: dysembryoplastic neuroepithelial tumours compared with other epileptogenic brain neoplasms.

BACKGROUND AND OBJECTIVES: Brain tumours responsible for longstanding partial epilepsy are characterised by a high prevalence of dysembryoplastic neuroepithelial tumour (DNT), whose natural evolution is much more benign than that of gliomas. The preoperative diagnosis of DNT, which is not yet feasible on the basis of available clinical and imaging data, would help optimise the therapeutic strategy for this type of tumour. This study tested whether [(11)C]-methionine positron emission tomography (MET-PET) could help to distinguish DNTs from other epileptogenic brain tumours. METHODS: Prospective study of 27 patients with partial epilepsy of at least six months duration related to a non-rapidly progressing brain tumour on magnetic resonance imaging (MRI). A structured visual analysis, which distinguished between normal, moderately abnormal, or markedly abnormal tumour methionine uptake, as well as various regions of interest and semiquantitative measurements were conducted. RESULTS: Pathological results showed 11 DNTs (41%), 5 gangliogliomas (18%), and 11 gliomas (41%). MET-PET visual findings significantly differed between the various tumour types (p<0.0002), regardless of gadolinium enhancement on MRI, and were confirmed by semiquantitative analysis (p<0.001 for all calculated ratios). All gliomas and gangliogliomas were associated with moderately or markedly increased tumour methionine uptake, whereas 7/11 DNTs had a normal methionine uptake, including all six located in the mesiotemporal structures. No DNT presented with a marked MET-PET abnormality. CONCLUSION: Normal MET-PET findings in patient with an epileptogenic and non-rapidly progressing brain tumour are suggestive of DNT, whereas a markedly increased tumour methionine uptake makes this diagnosis unlikely.

AIDS in Africa: what drugs do the carers want or need?

Our objectives were: (1) to discover requirements for treatment of patients with AIDS (PWAs) for health-care workers in eight English-speaking African countries; (2) to establish policies for supply of drugs, and develop a method for determining the contents of parcels (PWA-BOXes) for the relief of PWAs. Fifty-seven questionnaires were sent to non-government medical units treating PWAs, supplied by the charity Inter Care. Of these 37 units replied, two had no known PWAs, three were swamped by refugees; therefore, the total number analysed was 32. Only 24 units had access to HIV testing and the mean number of PWAs per unit was 58. The reported complications of AIDS were: diarrhoea 28 units; tuberculosis 27 units; pneumonia 28 units; sexually transmitted diseases 26; candidiasis 28 units; and herpes zoster 20. Lists of drug requirements were received. We present a protocol for calculation of contents of PWA-BOXes in the hope that this will provide guidelines for other workers in this field.

PIP: Inter Care, a UK charitable organization, provides essential drugs to 120 medical units in Africa. To upgrade support to units caring for substantial numbers of acquired immunodeficiency syndrome (AIDS) patients, Inter Care sent a questionnaire to 57 of its small rural hospitals and health and maternity units. Of the 37 units that returned the questionnaire, 24 reported access to human immunodeficiency virus (HIV) laboratory tests while another seven relied on clinical diagnostic methods. The number of AIDS patients treated per month ranged from 0 to 200 (mean, 50). Diseases and conditions most commonly associated with AIDS included diarrhea, pneumonia, candidiasis, tuberculosis, and sexually transmitted diseases. The most commonly used drugs were metronidazole, micronazole oral gel, and oxytetracycline. On the basis of these findings, Inter Care was able to modify the contents of AIDS boxes provided to its affiliates. An assumption was made that a patient with AIDS spends only two weeks in the hospital before death given the rapid progression of the disease in Africa. The drugs supplied vary according to specific requests and the type of facility, but seek to treat the AIDS-related conditions identified in the survey with the least expensive drug available. Also provided, depending on need, are HIV test kits and educational posters.