Preparations for a European R&D roadmap for an inertial fusion demo reactor

A European consortium of 15 laboratories across nine nations have worked together under the EUROFusion Enabling Research grants for the past decade with three principle objectives. These are: (a) investigating obstacles to ignition on megaJoule-class laser facilities; (b) investigating novel alternative approaches to ignition, including basic studies for fast ignition (both electron and ion-driven), auxiliary heating, shock ignition, etc.; and (c) developing technologies that will be required in the future for a fusion reactor. A brief overview of these activities, presented here, along with new calculations relates the concept of auxiliary heating of inertial fusion targets, and provides possible future directions of research and development for the updated European Roadmap that is due at the end of 2020. This article is part of a discussion meeting issue 'Prospects for high gain inertial fusion energy (part 2)'.

Whole-beam self-focusing in fusion-relevant plasma

Fast ignition inertial confinement fusion requires the production of a low-density channel in plasma with density scale-lengths of several hundred microns. The channel assists in the propagation of an ultra-intense laser pulse used to generate fast electrons which form a hot spot on the side of pre-compressed fusion fuel. We present a systematic characterization of an expanding laser-produced plasma using optical interferometry, benchmarked against three-dimensional hydrodynamic simulations. Magnetic fields associated with channel formation are probed using proton radiography, and compared to magnetic field structures generated in full-scale particle-in-cell simulations. We present observations of long-lived, straight channels produced by the Habara-Kodama-Tanaka whole-beam self-focusing mechanism, overcoming a critical barrier on the path to realizing fast ignition. This article is part of a discussion meeting issue 'Prospects for high gain inertial fusion energy (part 2)'.

Calibration of X-ray spectrometers for opacity experiments at the Orion laser facility (invited)

Accurately calibrated and characterised x-ray diagnostics are a key requirement in the fielding of experiments on the Orion laser where absolute measurements of x-ray emission are used to underpin the validity of models of emissivity and opacity. Diffraction crystals are used in spectrometers on Orion to record the dispersed spectral features emitted by the laser produced plasma to obtain a measurement of the plasma conditions. The ability to undertake diffraction crystal calibrations supports the successful outcome of these Orion experiments. This paper details the design and commissioning of a system to undertake these calibrations in the energy range 2.0 keV to approximately 8.5 keV. Improvements to the design are detailed which will extend the commissioned range of energies to below 1 keV.

The role of urethral samples in the diagnosis of gonorrhoea in women

We studied the value of carrying out urethral samples in women to diagnose gonorrhoea. All cases of genital gonorrhoea in women were identified (between 1 October 2000 and 30 September 2001) at the Whittall Street Clinic and the genitourinary medicine department at the Coventry and Warwickshire Hospital. Two hundred and twenty-four cases of female urethral gonorrhoea were identified. In 20 cases (6.3%) the urethra was the sole site of the infection. At the Whittall Street Clinic, we had to carry out 643 urethral samples in order to treat one additional case of gonorrhoea. On the other hand, 1204 urethral samples were requested to treat one additional case of female gonorrhoea at the Coventry and Warwickshire Hospital. In both units, use of the Gram-stained urethral smear permitted early treatment in only 1.8% of cases of genital gonorrhoea. Units with low prevalence of gonorrhoea should consider abandoning urethral samples for the diagnosis of gonorrhoea in women.

Lineshape spectroscopy with a very high resolution, very high signal-to-noise crystal spectrometer

We have developed a high-resolution x-ray spectrometer for measuring the shapes of spectral lines produced from laser-irradiated targets on the Orion laser facility. The instrument utilizes a spherically bent crystal geometry to spatially focus and spectrally analyze photons from foil or microdot targets. The high photon collection efficiency resulting from its imaging properties allows the instrument to be mounted outside the Orion chamber, where it is far less sensitive to particles, hard x-rays, or electromagnetic pulses than instruments housed close to the target chamber center in ten-inch manipulators. Moreover, Bragg angles above 50° are possible, which provide greatly improved spectral resolution compared to radially viewing, near grazing-incidence crystal spectrometers. These properties make the new instrument an ideal lineshape diagnostic for determining plasma temperature and density. We describe its calibration on the Livermore electron beam ion trap facility and present spectral data of the K-shell emission from highly charged sulfur produced by long-pulse as well as short-pulse beams on the Orion laser in the United Kingdom.

Observations of the effect of ionization-potential depression in hot dense plasma

The newly commissioned Orion laser system has been used to study dense plasmas created by a combination of short pulse laser heating and compression by laser driven shocks. Thus the plasma density was systematically varied between 1 and 10  g/cc by using aluminum samples buried in plastic foils or diamond sheets. The aluminum was heated to electron temperatures between 500 and 700 eV allowing the plasma conditions to be diagnosed by K-shell emission spectroscopy. The K-shell spectra show the effect of the ionization potential depression as a function of density. The data are compared to simulated spectra which account for the change in the ionization potential by the commonly used Stewart and Pyatt prescription and an alternative due to Ecker and Kröll suggested by recent x-ray free-electron laser experiments. The experimental data are in closer agreement with simulations using the model of Stewart and Pyatt.

Evidence that fibrinogen γ' directly interferes with protofibril growth: implications for fibrin structure and clot stiffness

BACKGROUND

Fibrinogen contains an alternatively spliced γ-chain (γ'), which mainly exists as a heterodimer with the common γA-chain (γA/γ'). Fibrinogen γ' has been reported to inhibit thrombin and modulate fibrin structure, but the underlying mechanisms are unknown.

OBJECTIVE

We aimed to investigate the molecular mechanism underpinning the influence of γ' on fibrin polymerization, structure and viscoelasticity.

METHODS

γA/γA and γA/γ' fibrinogens were separated using anion exchange chromatography. Cross-linking was controlled with purified FXIIIa and a synthetic inhibitor. Fibrin polymerization was analyzed by turbidity and gel-point time was measured using a coagulometer. We used atomic force microscopy (AFM) to image protofibril formation while final clot structure was assessed by confocal and scanning electron microscopy. Clot viscoelasticity was measured using a magnetic microrheometer.

RESULTS

γA/γ' fibrin formed shorter oligomers by AFM than γA/γA, which in addition gelled earlier. γA/γ' clots displayed a non-homogenous arrangement of thin fibers compared with the uniform arrangements of thick fibers for γA/γA clots. These differences in clot structure were not due to thrombin inhibition as demonstrated in clots made with reptilase. Non-cross-linked γA/γA fibrin was approximately 2.7 × stiffer than γA/γ'. Cross-linking by FXIIIa increased the stiffness of both fibrin variants; however, the difference in stiffness increased to approximately 4.6 × (γA/γA vs. γA/γ').

CONCLUSIONS

Fibrinogen γ' is associated with the formation of mechanically weaker, non-uniform clots composed of thin fibers. This is caused by direct disruption of protofibril formation by γ'.

Increased prevalence of non-alcoholic fatty liver disease in European women with a history of gestational diabetes

AIMS/HYPOTHESIS

Non-alcoholic fatty liver disease (NAFLD) is common in type 2 diabetes but it is unknown whether NAFLD is prevalent in European women at risk of type 2 diabetes. We studied the prevalence of, and risk factors for, NAFLD in European women with previous gestational diabetes (GDM) at high risk of type 2 diabetes.

METHODS

A total of 110 women with previous GDM and 113 without previous GDM, with non-diabetic glucose tolerance were recruited retrospectively from antenatal databases. Participants underwent liver ultrasound scan examination, anthropometry and blood sampling for liver function tests and to determine levels of fasting lipids, NEFA and insulin and glucose concentrations in order to derive insulin sensitivity and insulin secretion indices (HOMA%S and HOMA%B, respectively).

RESULTS

There was no significant difference in BMI in women with previous GDM compared with those without previous GDM (28.9 ± 0.6 vs. 27.9 ± 0.6 kg/m(2), respectively; p = 0.12). Women with previous GDM had higher fasting and 2 h glucose concentrations following a 75 g OGTT ([mean ± SEM] fasting glucose 5.3 ± 0.1 vs. 5.1 ± 0.1 mmol/l, p = 0.02; 2 h glucose 6.8 ± 0.2 vs. 5.8 ± 0.3 mmol/l, p = 0.02), dyslipidaemia (LDL-cholesterol 3.3 ± 0.1 vs. 2.8 ± 0.1 mmol/l; HDL-cholesterol [median {interquartile range}] 1.3 [1.2-1.6] vs. 1.8 [1.5-1.9] mmol/l; triacylglycerol 1.3 [0.9-1.6] vs. 1.0 [0.7-1.7] mmol/l, all p ≤ 0.03), higher insulin secretion and lower insulin sensitivity. NAFLD prevalence was greater in women with previous GDM compared with those without previous GDM: 38% (95% CI 28-47%) vs. 17% (95% CI 10-24%), p = 0.001. In multiple logistic regression analysis, lower insulin sensitivity and raised serum alanine transaminase concentrations were associated with NAFLD.

CONCLUSIONS/INTERPRETATION

NAFLD is prevalent in European women with previous GDM. Impaired insulin sensitivity and increased liver transaminase activity are closely associated with NAFLD in these women.

Combined hepatic artery and segmental portal vein occlusion in antiphospholipid syndrome

Antiphospholipid syndrome can have various clinical presentations, two of the most common being arterial and venous thrombosis. It is, however, unusual for them to occur in combination. We report here a case of combined hepatic artery and segmental portal venous occlusion in a 32-year-old patient who was shown to have a lupus anticoagulant. There have been no previous reports of thrombosis occurring simultaneously in the coeliac axis and the portal vein. Computerised tomography, Doppler ultrasound scanning and selective visceral angiography were used to demonstrate the anatomical lesions. The patient was treated medically with unfractionated heparin leading to a favourable clinical outcome. The diagnosis and management of this case is discussed with reference to the current literature on visceral thrombosis and antiphospholipid antibody syndrome.

The relationship between lower limb symptoms and superficial and deep venous reflux on duplex ultrasonography: The Edinburgh Vein Study

BACKGROUND

Previous work from this group has demonstrated the relationships between lower limb symptoms and the presence and severity of trunk varicose veins as seen on clinical examination to be generally weak, symptom specific, and gender dependent.

OBJECTIVE

This study was undertaken to investigate the relationships in the general population between lower limb symptoms and the presence of superficial or deep venous reflux.

METHODS

A cross-sectional study was made of an age-stratified random sample of 1566 subjects (699 men and 867 women) aged 18 to 64 selected from 12 general practices in Edinburgh, Scotland. Subjects completed a self-administered questionnaire regarding symptoms (heaviness/tension, a feeling of swelling, aching, restless legs, cramps, itching, tingling) and underwent duplex ultrasound examination of the superficial and deep venous systems of both legs. Reflux of 0.5 seconds or greater was considered pathologic. Deep venous reflux was defined as reflux in at least the popliteal vein.

RESULTS

There was a significant positive relationship between isolated superficial reflux and the presence of heaviness/tension (P <.025, both legs) and itching (P =.002, left leg) in women. Isolated superficial reflux in men was not significantly positively associated with any symptom. Isolated deep venous reflux was not significantly related to any symptom in either leg in either sex. Combined reflux was related to a feeling of swelling (P =.018, right leg; P =.0022, left leg), cramps (P =.0049, left leg) and itching (P =.0043, left leg) in men, and aching (P =.03, right leg) and cramps (P =.026, left leg) in women.

CONCLUSION

In the general population, only certain lower limb symptoms were related to the presence of reflux on duplex ultrasound scanning. The strongest relationships were observed in the left legs of men with combined superficial and deep reflux.

In vivo sensitization of ovarian tumors to chemotherapy by expression of E. coli purine nucleoside phosphorylase in a small fraction of cells

This report examines a major barrier to suicide gene therapy in cancer and other diseases: namely, bystander cell killing. Existing vectors for in vivo gene delivery are inefficient and often transduce or transfect less than 1% of target cells. The E. coli PNP gene brings about cellular necrosis under conditions when 1 in 100 to 1 in 1000 cells express the gene product in vitro. In vivo bystander killing at or near this magnitude has not been reported previously. In the present experiments, transfection of cells with the E. coli PNP gene controlled by a SV40 promoter resulted in 30 nmol 6-methyl purine deoxyriboside (MeP-dR) converted per milligram tumor cell extract per hour (or conversion units (CU)). This level of expression led to elimination of entire populations of tumor cells in vitro after treatment with MeP-dR. Much earlier killing was observed using a tat transactivated E. coli PNP vector (approximately seven-fold higher activity, 230 CU). In vivo effects on tumor growth were next examined. Human ovarian tumors transfected with E. coli PNP were excised 5 days after i.p. implantation from the peritoneal cavities of mice in order to determine both E. coli PNP enzymatic activity and the fraction of cells expressing the gene. PNP activity at 5 days after gene transfer was approximately 170 CU and was expressed in approximately 0.1% of the tumor cells as judged by in situ hybridization. The expression of E. coli PNP at this level produced a 30% increase in life span (P < 0.001) and 49% reduction in tumor size (P < 0.005) after MeP-dR treatment, as compared with control tumors. Our observations lead to the conclusion that pronounced bystander killing by E. coli PNP is conferred in vivo, and that vectors capable of transgene expression in as few as one in 1000 cells can produce substantial antitumor effects if expression on a per cell basis is very high.

What pathological components indicate carotid atheroma activity and can these be identified reliably using ultrasound?

OBJECTIVE

The aim of this project was to determine whether histological features of 'active' plaque as described in the coronary circulation following acute myocardial infarction were similar in the carotid circulation, and whether these factors could be detected ultrasonically.

METHOD

Endarterectomy specimens were prospectively collected, and examined histologically and assessed by two observers for ulceration, inflammation, size of necrotic core, thickness of fibrous cap, haemorrhage and luminal thrombosis. Ultrasound of the plaque obtained preoperatively was similarly coded (blind to pathology) and compared with the pathology.

RESULTS

In 42 endarterectomy specimens, there was a highly significant relationship between a thin fibrous cap and a large necrotic core (P<0.002), irregular plaque contour (P<0.05) and ulceration (P<0.01) and between a large necrotic core (P<0.002) and ulceration and inflammation (P<0.05). Increasing amounts of necrosis were associated with more surface thrombosis (P<0.02). Ultrasound detected the thickness of the fibrous cap and 'any necrosis or haemorrhage' with some reliability (kappas are 0.53 and 0.5, respectively), but not ulceration, necrosis or haemorrhage on their own.

CONCLUSION

Features corresponding to active atheromatous plaque are similar in the carotid and coronary arteries, and some of these, namely lucent areas in the plaque (corresponding to necrosis or haemorrhage) and the thickness of the fibrous cap, can be determined reliably with ultrasound.

What are the symptoms of varicose veins? Edinburgh vein study cross sectional population survey

OBJECTIVE

To define the relations between age, sex, lower limb symptoms, and the presence of trunk varicose veins on clinical examination.

DESIGN

Cross sectional population study.

SETTING

12 general practices with catchment areas geographically and socioeconomically distributed throughout Edinburgh.

PARTICIPANTS

An age stratified random sample of 1566 people (699 men and 867 women) aged 18-64 selected from the computerised age-sex registers of participating practices.

MAIN OUTCOME MEASURES

Self administered questionnaire on the presence of lower limb symptoms and physical examination to determine the presence and severity of varicose veins.

RESULTS

Women were significantly more likely than men to report lower limb symptoms such as heaviness or tension, swelling, aching, restless legs, cramps, and itching. The prevalence of symptoms tended to increase with age in both sexes. In men, only itching was significantly related to the presence and severity of trunk varices (linear test for trend, P=0.011). In women there was a significant relation between trunk varices and the symptoms of heaviness or tension (P</=0.001), aching (P</=0.001), and itching (P</=0.005). However, the level of agreement between the presence of symptoms and trunk varices was too low to be of clinical value, especially in men.

CONCLUSIONS

Even in the presence of trunk varices, most lower limb symptoms probably have a non-venous cause. Surgical extirpation of trunk varices is unlikely to ameliorate such symptoms in most patients.

Color Doppler imaging in untreated high- and normal-pressure open-angle glaucoma

PURPOSE

To evaluate ocular blood flow velocity indices in untreated primary open-angle glaucoma (POAG) and normal pressure glaucoma (NPG).

METHODS

Twenty-five untreated patients with NPG, 23 untreated patients with POAG, and 26 age-matched normal control subjects underwent color Doppler imaging for the measurement of blood flow velocity in the central retinal and ophthalmic arteries. Neither the patients nor the control subjects were using systemic beta-blockers or calcium channel blockers. After log transformation of non-normal data, group differences were compared with a one-way analysis of variance followed by unpaired t-test with the Bonferroni correction. Statistical significance was set at P < 0.05.

RESULTS

The central retinal artery end diastolic velocity was significantly lower in patients with POAG than in normal subjects. The ophthalmic artery peak systolic velocity (PSV) was significantly greater in patients with POAG than in those with NPG and normal subjects. The resistance index (RI) of both the ophthalmic and central retinal arteries was significantly greater in patients with POAG than in normal subjects, and the central retinal artery RI was significantly greater in those with NPG than in normal subjects. Systemic pulse pressure and systolic blood pressure were significantly greater in patients with POAG compared with normal subjects. Multiple regression analysis showed a significant relation between ophthalmic artery PSV and intraocular pressure (but not with any of the cardiovascular parameters) in the POAG group. Chi-square analysis found significantly more systemic vascular disease in patients with NPG and POAG compared with that of normal subjects.

CONCLUSIONS

There was an increased resistance to blood flow in the central retinal artery of untreated patients with NPG and POAG and also in the ophthalmic artery of patients with POAG. The ophthalmic artery peak systolic velocity was elevated in untreated patients with POAG. Altered ocular circulation (with different patterns of presentation) appears to be common to patients with NPG and patients with POAG.

Surveillance imaging of the operated artery does not alter clinical outcome following carotid endarterectomy

Clinical outcome was studied in 243 patients undergoing 260 carotid endarterectomies; 166 of these patients underwent serial postoperative surveillance imaging. Including perioperative events, cumulative freedom from ipsilateral stroke was 86 and 82 per cent at 5 and 10 years respectively; the mean incidence of ipsilateral stroke was 1.8 per cent per annum. Twenty patients (8 per cent) suffered cerebral ischaemic events in the hemisphere of the operated side during follow-up: eight transient ischaemic attacks (TIA) and 12 strokes (only two preceded by TIA). Two symptomatic patients were found to have occluded the operated artery but the remainder had no evidence of significant recurrent disease. Cumulative freedom from occlusion or severe (greater than 70 per cent) recurrent stenosis was 87 and 78 per cent at 5 and 10 years respectively; the mean incidence of recurrence of significant disease was 2.2 per cent per annum. No revisional surgery was performed on the operated arteries. In its current format, neither clinical nor surveillance imaging could have prevented any of the strokes observed during follow-up.

Choroidal cells in ovarian cyst fluid: a case report

BACKGROUND

The ovary is conspicuous for the wide diversity of histologic tumor types that it contains. Unusual or rare tumors may present diagnostic difficulty on cytologic examination.

CASE

A 36-year-old woman presented with an 80-mm cystic lesion in the left ovary. Fine needle aspiration provided 30 ml of transparent, light yellow fluid. On cytologic examination, numerous clusters and rosettes of benign cells, resembling choroid plexus cells, were seen. Surgical resection confirmed the presence of an ependymal cyst adjacent to a mature cystic teratoma (dermoid cyst).

CONCLUSION

We report this unique case in order to alert cytologists unfamiliar with cerebrospinal fluid cytopathology to the rare entity of ovarian ependymal cysts.

Development of drug targeting based on recombinant expression of the chicken avidin gene

The chemistry required for covalent biotinylation of drugs, radiopharmaceuticals and other ligands is highly developed, and a large number of biotinylated reagents can be readily synthesized. In order to investigate whether expression of avidin cDNA in mammalian cells might be useful as part of a drug targeting strategy, we transiently expressed the avidin gene in two human tumor cell lines (the cervical carcinoma cell line, HeLa, and the liver derived line, Hep G2). Avidin protein as detected by either immunohistochemistry or binding of streptavidin-biotin complexes was present and functional following transient expression. This result indicated that the mechanisms underlying avidin oligomerization which are necessary for proper protein folding are present within mammalian carcinoma cell lines. Next, we generated a producer cell line (derived from psi2) capable of releasing a recombinant retrovirus encoding chicken avidin, and a tumorigenic murine breast cancer cell line (16/C) with stable avidin expression. We show that these cell lines are suitable for conferring functional expression of avidin in vitro. These experiments establish a means by which avidin gene expression can be explored as a mechanism for targeted gene delivery of biotin-derivitized drugs in vitro, and have important implications for utilization of this strategy in vivo.

Measurement of ocular blood flow velocity using colour Doppler imaging in low tension glaucoma

The purpose of this study was to compare the velocity of blood flow and vascular resistance measured by colour Doppler imaging in the ophthalmic and central retinal arteries in 34 eyes of 34 patients (mean age 68.1 years) with low tension glaucoma (LTG) and 17 eyes of 17 age-matched normal controls (mean age 65.2 years). The Acuson 128 machine (using a 7.5 MHz probe) was used to measure peak systolic velocity (PSV), end-diastolic velocity (EDV) and resistive index (RI). The EDV of the ophthalmic artery (OA) in the LTG was significantly (p = 0.04) less than in the normal control group. There was a significant (p = 0.02) increase in the vascular RI of both the OA and central retinal artery in the LTG group compared with the normal controls. The OA RI increased with age (r = 0.61, p = 0.0001), and the OA EDV decreased with age (r = -0.50, p = 0.003), in the LTG group but not in the normal control group. The results suggest an increased resistance to blood flow in the ophthalmic and central retinal arteries of LTG patients.

Fate of the non-operated carotid artery after contralateral endarterectomy

The long-term fate of the non-operated internal carotid artery (ICA) in 219 patients undergoing contralateral carotid endarterectomy was studied; 151 patients underwent serial postoperative imaging of the vessel. Cumulative freedom from stroke in the non-operated hemisphere was 99, 96 and 86 per cent at 1, 5 and 10 years respectively, giving a mean incidence of stroke of 1 per cent per annum. Only one stroke was preceded by a transient ischaemic attack and no stroke was associated with severe (70 per cent or greater) stenosis of the ICA. Ten patients (7 per cent) with initially mild or moderate disease of the non-operated ICA progressed to severe stenosis during follow-up, but only three became symptomatic and, in each case, the onset of symptoms preceded recognition of disease progression. The long-term risk of stroke in the non-operated ICA territory is very small. Of practical importance is that none of the observed strokes could have been prevented by postoperative surveillance of this type.

Malignant fibrous histiocytoma of the maxilla--a report of two cases

Two cases of malignant fibrous histiocytoma of the maxilla are reported. The tumours were excised via a combined temporal and intra-oral approach in order to gain adequate surgical access and minimise the aesthetic deformity. One patient required orbital exenteration.

Effects of girdling time on growth, yield, and fruit maturity of the low chill peach cultivar Flordaprince

Low chill Flordaprince peach trees in subtropical Australia were trunk-girdled at 1 of 3 times during fruit development: pre stone hardening (pre SH), post stone hardening (post SH), and 2 weeks before expected first harvest (BFH). Measures were made of fruit and shoot growth, harvest data, and starch levels in different tree parts. The pre SH girdling gave the greatest (P<0.05) increase in fruit size during stage 2 of fruit development, and pre and post SH girdling treatments gave progressively earlier (P<0.05) and shorter (10 days v. 24 days for control) main harvest period. Girdling resulted in greater numbers of fruit of larger, desirable marketable size (>90 g) than the control, although the latter caught up in average yield because of longer development period and some variability in numbers of fruit per tree. Split pip was not a problem. Fruit sugar content was significantly (P<0.05) higher with post SH and BFH girdling treatments than with control or pre SH treatment. Girdling temporarily increased starch levels in the leaves and shoots and reduced shoot growth.

The role of monoclonal antibodies in brain tumour diagnosis and cerebrospinal fluid (CSF) cytology

This paper reviews the diagnostic role of monoclonal antibody immunohistochemistry in a series of 189 brain tumour biopsies and 22 cases of neoplastic meningitis. The diagnostic monoclonal antibody panel, which includes markers for glial, neural, epithelial and lymphoid differentiation antigens, was used to test a wide variety of cerebral and spinal tumours by indirect immunofluorescence and immunoperoxidase techniques on unfixed frozen sections. Gliomas, meningiomas, schwannomas, medulloblastomas, choroid plexus tumours, cerebral lymphomas and metastatic carcinomas could all be reliably differentiated by means of their characteristic antigenics profiles, as defined by their patterns of reactivity with the antibody panel. Confident diagnosis was possible even in very poorly differentiated tumours and in biopsies distorted by surgical squeeze artefact, where paucity of morphological clues made diagnosis by conventional histological methods difficult or impossible. It was estimated that use of the antibody panel was responsible for, or made a significant contribution towards the final diagnosis in approximately 20% of cases. The monoclonal reagents were also found to be of great value in the detection and characterisation of neoplastic cells in CSF specimens from patients with malignant meningitis. Malignant cells were detected in 73% of cases and characterised in 16% of cases by routine cytological techniques. Employing monoclonal immunocytology however, these figures were improved to 95% and 95% respectively. Our findings suggest that patients with neoplastic meningitis can be spared prolonged investigation and inappropriate management by the early detection and characterisation of malignant cells in CSF using panels of monoclonal antibodies.

Monoclonal antibody UJ 127:11 detects a 220,000-240,000 kdal. glycoprotein present on a sub-set of neuroectodermally derived cells

The monoclonal antibody UJ 127-11 was raised following immunization of mice with human foetal brain and subsequent somatic cell hybridization of spleen cells with the mouse myeloma cell line P3-X63-Ag8-653. Studies on normal foetal and adult tissues show that, by indirect immunofluorescence, the antigen recognized by UJ 127:11 is restricted in its expression to cells of neural rather than glial origin. Neural tumours such as neuroblastoma, medulloblastoma and ganglioglioma (neural component) bind the monoclonal antibody whereas malignancies originating from glial cells do not bind UJ 127:11. Biochemically the monoclonal antibody has been shown to bind to a glycoprotein of 220,000-240,000 mol. wt. under reducing and non-reducing conditions. Despite similarities in the molecular weight between human fibronectin and the antigen recognized by UJ 127:11, they have different serological and biochemical characteristics, suggesting that the monoclonal antibody is not binding to either cell or plasma fibronectin.