Hairy cell leukaemia (HCL) has distinct clinical, morphological and immunophenotypic features with no recurrent cytogenetic or molecular abnormalities reported until the recent description of the BRAF V600E mutation in patients with classical HCL. The incidence of this mutation was sought in 27 patients with either classical HCL or HCL variant by an allele-specific PCR approach and findings related to morphology, cytochemistry and immunophenotype. A high degree of correlation was noted between the presence of BRAF V600E and established diagnostic criteria in 26/27 patients with HCL/HCL variant. Detection of the BRAF V600E mutation is therefore a useful adjunct in the differential diagnosis of HCL and HCL variant and highlights the value of a multifaceted approach to the diagnosis of this malignancy.

As Schwann cells possess regenerative capabilities there is intense interest concerning their role in central nervous system (CNS) regeneration. We report on a case of an intramedullary schwannoma involving the conus medullaris and spinal cord above it. We discuss the possible origin of these cells and the mechanisms by which these cells may invade the CNS. We offer imaging and discuss experimental studies to support our hypothesis. This case concerns a 48-year-old man, who presented with a 6-month history of bilateral lower extremity weakness. Magnetic resonance imaging (MRI) revealed an intramedullary tumour extending from the conus to T11. At operation, following laminectomy and durotomy, a schwannoma was dissected free from the conus. Total gross resection of tumour was achieved. The patient made an uneventful and full recovery. This case shows that Schwann cells can invade the CNS. Manipulation of the transitional zone astrocytic barrier may offer a potential avenue for Schwann cells to enter the CNS in pathological states.

The Pumped Divertor phase of JET has involved the use of plasma configurations with complex control requirements. Therefore, a new JET Plasma Shape Controller (SC) was developed. This system was brought into operation in February 94 and had been used for all the Mark I campaign (94–95). The experience gained during that campaign, and the new and more stringent control requirements resulting from the introduction in JET of the Mark II divertor have prompted the development of a new and more powerful version of Shape Controller. This paper describes the new system, and the performance achieved during the Mark II campaign.

Computerizedtomography (CT) andmagnetic resonance imaging (MRI) have assumedpivotal roles in modernneurosurgery. Byallowing the surgeonaccuratelyandnon-invasively tovisualize the relatively inaccessible central nervous system, space-occupying lesionscanoftenbediagnosedbeforetheyhavecaused muchdamage. This is of particular importance with headinjuries andother neurosurgical emergencies where thetimebetweenonset of initial symptomsand progressionto irreversible braindamage is oftenshort andtheprognosis is inverselyproportional tothetime before appropriate treatment is instigated. IntheUKandRepublicofIreland,mostpatientswith headinjuriesorotheracuteintracranial lesionsarefirst seenandassessedindistrict hospitals before referral to a neurosurgical centre. Withthe widespreadavailabilityofCTandMRI, manypatientsundergoscanningin these hospitals before consultationwiththe neurosurgicalcentre.Despitethetheoreticaladvantageofsucha sequence of events, avoidable delay inthe diagnosis andmanagement of thesepatients has beenreported1. Voice communicationbytelephone betweena nonspecialist anda neurosurgeonhas beenshowntobe ineffective for accurately describing emergencyCT scans inhead-injuredpatients2. Withfundingfromthe EuropeanUnionunder the Telematique initiative, we have sought to remedythis problembydevelopingan emergencytelemedicine network linking all major district hospitals inthe IrishRepublic tobothdepartments of neurosurgery there. This systemhas been operational since 1993 andallows the rapidtransmissionof CTandMRimages, sothat thereferringdoctor andneurosurgeoncanviewpatients’ scans as an adjunct to telephone communication(Fig1). We describe three cases whichillustrate some of the advantages anddisadvantages of anemergencytelemedicineneurosurgicalnetwork.Thenetworkitselfhas beendescribedindetail elsewhere3.

Two pumped diverters have been installed and tested in JET under ITER relevant conditions. A closed divertor is found to increase the particle and impurity exhaust rate in agreement with code modelling. Excellent power handling is demonstrated, allowing high current discharges with record stored energy (15 MJ) and quasi-steady-state discharges with high fusion triple product (4 x 10(20) m(-3) s keV). The ITERH93-P confinement scaling law is confirmed over abroad range and a more favourable beta scaling is found. No hysteresis is found in the II-mode power threshold. A data base of highly radiating discharges including impurity seeding describes the relationship between radiated power, impurity concentration and density. First results of high performance with optimised magnetic shear are presented. Strong internal confinement barriers develop despite the relatively small input of toroidal momentum and particle fuelling from ICRH and NBI.

All major JET systems have been fully commissioned for D-T and the DTE1 series of experiments has started with the D-T fuel mixture and operating conditions foreseen for ITER. In the area of ITER physics, significant results have been produced in both D-D and D-T. In D-D, the LH threshold power database has been extended, the bounds on edge-electron temperature and density in ELMy H-modes have been defined and the advantages of Types I and III ELMy discharges have been compared. In D-T plasmas, the isotope effect on H-mode threshold power and transport has been determined so that a more accurate assessment can be made of the ignition margin and heating requirements for ITER. Trace tritium experiments have provided first particle transport measurements and an assessment of the ITER reference ion-cyclotron resonance-frequency heating scenarios has been started, In the area of fusion performance, record D-D neutron yields have been obtained by controlling the plasma and current profiles in hot ion ELM-free H-modes and optimized shear modes. In D-T, internal transport barriers have been readily established in optimized shear discharges and Alfven eigenmodes have been observed.

Pre-operative stress is well documented and multifactorial in aetiology.Anxious patients often show further signs of stress immediately prior to indaction of anaesthesia and during pre-oxygenation.In our hospital standard black rubber masks are used for preoxygenation.Several authors have reported the use of scented oils painted onto the rubber face masks facilitating inhalationalinduction in children 1.The objective of this study was to assess whether adult patients had a preference for the type of face mask used for preoxygenation prior to the induction of anaesthesia.100 patients ASA class 1, 2 or 3 aged between 17 and 19 years were chosen at random from the theatre list for elective surgery to be included in the study.The patients were visited on the ward.It was explai ned that they would be brought directly in to the operatin g room prior to surgery.An intravenous cannula would be sited and baseline monitoring established.They would then be given oxygen to breathe for 2 rains prior to the induction of anaesthesia through either an anatomical black rubber face mask or 'King System's Fresh Scent' (mint scented) face mask.A brief description of each mask was given, alternating the order between patients.The patients were allowed to handle and breathe through the masks and then express any preference for one or other mask.

oesophagus had oesophageal bile reflux in the presence of a normal acid score indicating that alkaline reflux may dilute the pH to give a "normal" acid profile.These data suggest that neither gastric or oesophageal alkaline shift reliably predict gastrooesophageal bile reflux.Such reflux may occur in the presence of both normal and acidic oesophageal pH profiles.

C-erB-2 oneoprotein expression detected immunohistochemically in primary breast cancer is a potent poor prognostic variable for patients including Irish women t.2.Also primary C-erB-2 expression indicates hormone resistance in recurrent breast cancer and relative tumour resistance to low intensity chemotherapy with mitoxanthrone (data in press).Forty young women (median age 41 years) had staining for C-erB-2 in their primary tumonrs; 11 showed positive staining and 29 did not.All subsequently had recurrences of breast cancer and were then given intensiv e chemotherapy with doxombicin 40 mg/m 2 intravenously and ifosfamide/ mesna 5 g/m 2 by intravenous infusion over 24 hours, with mesna alone for 8 hours.Cycles repeated at 21 day intervals to a total of 4 cycles in patients with responsive tumours.Response rates in recurrences (82% C-erB-2+VE vs 72% C-erB-2-ve) median response durations, and post-treatment survival were no different between patients on the basis of primary turnout C-erB-2 expression.This strongly suggests that young women with operable breast cancer and expression of C-erB-2 should be selected for intensive doxombicin based nee-adjuvant/adjuvant chemother apy.