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The biological pump supplies carbon to the oceans' interior, driving long-term carbon sequestration and providing energy for deep-sea ecosystems 1,2 . Its efficiency is set by transformations of newly formed particles in the euphotic zone, followed by vertical flux attenuation via mesopelagic processes 3 . Depth attenuation of the particulate organic carbon (POC) flux is modulated by multiple processes involving zooplankton and/or microbes 4,5 . Nevertheless, it continues to be mainly parameterized using an empirically derived relationship, the 'Martin curve' 6 . The derived power-law exponent is the standard metric used to compare flux attenuation patterns across oceanic provinces 7,8 . Here we present in situ experimental findings from C-RESPIRE 9 , a dual particle interceptor and incubator deployed at multiple mesopelagic depths, measuring microbially mediated POC flux attenuation. We find that across six contrasting oceanic regimes, representing a 30-fold range in POC flux, degradation by particle-attached microbes comprised 7-29 per cent of flux attenuation, implying a more influential role for zooplankton in flux attenuation. Microbial remineralization, normalized to POC flux, ranged by 20-fold across sites and depths, with the lowest rates at high POC fluxes. Vertical trends, of up to threefold changes, were linked to strong temperature gradients at low-latitude sites. In contrast, temperature played a lesser role at mid- and high-latitude sites, where vertical trends may be set jointly by particle biochemistry, fragmentation and microbial ecophysiology. This deconstruction of the Martin curve reveals the underpinning mechanisms that drive microbially mediated POC flux attenuation across oceanic provinces., (© 2024. The Author(s).)

Introduction: The long case examination is used to assess clinical competency in dental education. However, the academic literature, much of which is in medical education, highlights concerns regarding the relevancy and authenticity of the long case. To date, dental students' experiences of the long case have been under-researched. This study examines students' experiences and perceptions of the long case examination at an Australasian dental school., Materials and Methods: This study was a qualitative investigation. Students participated in interviews to discuss their perceptions and experiences of the long case examination. The interviews were voice-recorded and transcribed, and a thematic inductive analysis was undertaken., Results: Three main themes emerged from the data: stress, where students described stressors before, during and after the long case; fairness, where students positioned the long case as either fair or not fair; and confusion, where students spoke about their perceived lack of understanding of the examination process and procedures., Conclusion: The concerns students raised regarding stress, fairness and confusion are considered and ways in which the long case might be developed in order to support students' learning are presented. Alternative structures or practices that might be explored include greater calibration of examiners and cases, and enhancements to how students are prepared for and prepare for the examination. The results of this research will inform ongoing development of assessment practices., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Prevalence of atrial fibrillation (AF) is increasing, due partly to the ageing population. The Birmingham Atrial Fibrillation Treatment of the Aged (BAFTA) Trial, published in 2007, provided strong evidence of the effectiveness of warfarin at age≥80 years, but the impact on incidence of AF-related stroke and peripheral embolic vascular events is uncertain., Methods: We studied age-specific incidence and outcome of all AF-related incident strokes and systemic emboli from 2002 to 2012 in the Oxford Vascular Study., Results: Of 3096 acute cerebral or peripheral vascular events, 748 (24.2%) were AF-related. Of the 597 disabling/fatal incident ischaemic strokes, 369 occurred at age ≥80 years, of which 124 (33.6%) were in non-anticoagulated patients with known prior AF. There was no reduction in incident AF-related events after 2007 at all ages (n=231 vs 211; adjusted RR=1.11, 0.91 to 1.36, p=0.29) or at age ≥80 (137 vs 135, RR=1.15, 0.94 to 1.40, p=0.17). Scope for improved prevention at older ages was considerable. Among 208 patients with incident AF-related events at age ≥80 and known prior AF, only 19 (9.1%) were anticoagulated. Of the 189 patients not anticoagulated, 166 (87.8%) had no major disability prior to the event and 167 (88·4%) had a high embolism risk score, of whom 139 (83.2%) were also at low risk of complications. Yet, 125/167 (74.9%) were dead or institutionalised after the event. Potentially preventable embolic events outnumbered warfarin-related intracerebral haemorrhages by about 15-fold (280 vs 19), rising to 50-fold (189 vs 4) at age ≥80 years., Conclusions: We found no reduction in incidence of AF-related vascular events since publication of the BAFTA trial. A third of all disabling/fatal strokes occur in non-anticoagulated patients with known prior AF., Competing Interests: Conflicts of Interest: None declared., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Background: Urgent assessment is essential after stroke. Several countries have had public education campaigns, based on the FAST (Face-Arm-Speech-Time) test to reduce delays in seeking attention. However, the impact of these campaigns on patient behavior is uncertain., Methods: We prospectively determined patient behavior after incident major stroke (NIHSS > 3) in a UK population based study (Oxford Vascular Study) before (2002-2008) and after (2009-2013) introduction of the FAST TV-campaign and assessed any sustained impact of campaign continuation., Results: Among 668 consecutive patients with major stroke, medical attention was sought by a bystander in 553 (89·6%). Patients were more likely to present directly to emergency services (OR = 2·18, 95%CI:1·54-3·09, P < 0·0001) after the campaign and to arrive at hospital within 3 h (OR = 2·18, 1·55-3·06, P < 0·0001). Median [IQR] time to seeking attention fell from 53 [15-265] to 31 [7-120] minutes (P = 0·005) and median time to hospital arrival from 185 [88-885] to 119 [78-256] minutes (P < 0·0001). On time-series analysis improvements in hospital arrival within 3 h and use of emergency medical services were significantly associated to initiation of the campaign (aOR = 3·11, 1·53-6·29, P = 0·002; and 2·22, 1·05-4·67, P = 0·036, respectively), independent of trend, age, sex, ethnicity, educational level, social class, prior stroke and stroke severity, and have been sustained to 2013., Conclusion: Delays to seeking and receiving medical attention after major stroke in the UK. fell strikingly in 2009, coinciding with the start of the FAST TV campaign. That medical attention was sought by a bystander in nearly 90% of cases illustrates the importance of mass-media public education rather than focused programs in high-risk groups for major stroke., (© 2015 The Authors. International Journal of Stroke published by John Wiley & Sons Ltd on behalf of World Stroke Organization.)

Paraneoplastic neurological syndromes affecting the CNS are rare, presenting in less than 1% of all those with cancer. However, they account for significant disability and may respond to treatment. The pathogenesis of paraneoplastic neurological syndromes is presumed to relate to loss of self-tolerance spilling over from the immune attack on the underlying neoplasm. Testing for anti-neuronal antibodies is now available in most tertiary laboratories, enabling targeted therapies. While the evidence base for treatment is limited, the response to treatment can be largely determined based on the location of the target antigen; antibodies against cell surface antigens responding well to treatments targeting the humoral response. Intracellular antigen-target syndromes respond less well, but may theoretically respond best to T-cell based therapies. In both cases, aggressive tumor therapy is indicated.

Background: Prevalence of atrial fibrillation (AF) is >10% at age ≥80 years, but the impact of population aging on rates of AF-related ischemic events is uncertain., Methods and Results: We studied age-specific incidence, outcome, and cost of all AF-related incident strokes and systemic emboli from 2002 to 2012 in the Oxford Vascular Study (OXVASC). We determined time trends in incidence of AF-related stroke in comparison with a sister study in 1981 to 1986, extrapolated numbers to the UK population and projected future numbers. Of 3096 acute cerebral or peripheral vascular events in the 92 728 study population, 383 incident ischemic strokes and 71 systemic emboli were related to AF, of which 272 (59.9%) occurred at ≥80 years. Of 597 fatal or disabling incident ischemic strokes, 262 (43.9%) were AF-related. Numbers of AF-related ischemic strokes at age ≥80 years increased nearly 3-fold from 1981-1986 to 2002-2012 (extrapolated to the United Kingdom: 6621 to 18 176 per year), due partly to increased age-specific incidence (relative rate 1.52, 95% confidence interval 1.31-1.77, P=0.001), with potentially preventable AF-related events at age ≥80 years costing the United Kingdom £374 million per year. At current incidence rates, numbers of AF-related embolic events at age ≥80 years will treble again by 2050 (72 974/year), with 83.5% of all events occurring in this age group., Conclusions: Numbers of AF-related incident ischemic strokes at age ≥80 years have trebled over the last 25 years, despite the introduction of anticoagulants, and are projected to treble again by 2050, along with the numbers of systemic emboli. Improved prevention in older people with AF should be a major public health priority., (© 2014 American Heart Association, Inc.)

Background and Purpose: Long-term outcome information after transient ischemic attack (TIA) and stroke is required to help plan and allocate care services. We evaluated the impact of TIA and stroke on disability and institutionalization over 5 years using data from a population-based study., Methods: Patients from a UK population-based cohort study (Oxford Vascular Study) were recruited from 2002 to 2007 and followed up to 2012. Patients were followed up at 1, 6, 12, 24, and 60 months postevent and assessed using the modified Rankin scale. A multivariate regression analysis was performed to assess the predictors of disability postevent., Results: A total of 748 index stroke and 440 TIA cases were studied. For patients with TIA, disability levels increased from 14% (63 of 440) premorbidly to 23% (60 of 256) at 5 years (P=0.002), with occurrence of subsequent stroke being a major predictor of disability. For stroke survivors, the proportion disabled (modified Rankin scale >2) increased from 21% (154 of 748) premorbidly to 43% (273 of 634) at 1 month (P<0.001), with 39% (132 of 339) of survivors disabled 5 years after stroke. Five years postevent, 70% (483 of 690) of patients with stroke and 48% (179 of 375) of patients with TIA were either dead or disabled. The 5-year risk of care home institutionalization was 11% after TIA and 19% after stroke. The average 5-year cost per institutionalized patient was $99,831 (SD, 67 020) for TIA and $125,359 (SD, 91 121) for stroke., Conclusions: Our results show that 70% of patients with stroke are either dead or disabled 5 years after the event. Thus, there remains considerable scope for improvements in acute treatment and secondary prevention to reduce postevent disability and institutionalization.

Background: Outpatient management safely and effectively prevents early recurrent stroke after transient ischaemic attack (TIA), but this approach may not be safe in patients with acute minor stroke., Objective: To study outcomes of clinic and hospital-referred patients with TIA or minor stroke (National Institute of Health Stroke Scale score ≤3) in a prospective, population-based study (Oxford Vascular Study)., Results: Of 845 patients with TIA/stroke, 587 (69%) were referred directly to outpatient clinics and 258 (31%) directly to inpatient services. Of the 250 clinic-referred minor strokes (mean age 72.7 years), 237 (95%) were investigated, treated and discharged on the same day, of whom 16 (6.8%) were subsequently admitted to hospital within 30 days for recurrent stroke (n=6), sepsis (n=3), falls (n=3), bleeding (n=2), angina (n=1) and nursing care (n=1). The 150 patients (mean age 74.8 years) with minor stroke referred directly to hospital (median length-of-stay 9 days) had a similar 30-day readmission rate (9/150; 6.3%; p=0.83) after initial discharge and a similar 30-day risk of recurrent stroke (9/237 in clinic patients vs 8/150, OR=0.70, 0.27-1.80, p=0.61). Rates of prescription of secondary prevention medication after initial clinic/hospital discharge were higher in clinic-referred than in hospital-referred patients for antiplatelets/anticoagulants (p<0.05) and lipid-lowering agents (p<0.001) and were maintained at 1-year follow-up. The mean (SD) secondary care cost was £8323 (13 133) for hospital-referred minor stroke versus £743 (1794) for clinic-referred cases., Conclusion: Outpatient management of clinic-referred minor stroke is feasible and may be as safe as inpatient care. Rates of early hospital admission and recurrent stroke were low and uptake and maintenance of secondary prevention was high.

Background: Transient isolated brainstem symptoms (eg, isolated vertigo, dysarthria, diplopia) are not consistently classified as transient ischaemic attacks (TIAs) and data for prognosis are limited. If some of these transient neurological attacks (TNAs) are due to vertebrobasilar ischaemia, then they should be common during the days and weeks preceding posterior circulation strokes. We aimed to assess the frequency of TNAs before vertebrobasilar ischaemic stroke., Methods: We studied all potential ischaemic events during the 90 days preceding an ischaemic stroke in patients ascertained within a prospective, population-based incidence study in Oxfordshire, UK (Oxford Vascular Study; 2002-2010) and compared rates of TNA preceding vertebrobasilar stroke versus carotid stroke. We classified the brainstem symptoms isolated vertigo, vertigo with non-focal symptoms, isolated double vision, transient generalised weakness, and binocular visual disturbance as TNAs in the vertebrobasilar territory; atypical amaurosis fugax and limb-shaking as TNAs in the carotid territory; and isolated slurred speech, migraine variants, transient confusion, and hemisensory tingling symptoms as TNAs in uncertain territory., Findings: Of the 1141 patients with ischaemic stroke, vascular territory was categorisable in 1034 (91%) cases, with 275 vertebrobasilar strokes and 759 carotid strokes. Isolated brainstem TNAs were more frequent before a vertebrobasilar stroke (45 of 275 events) than before a carotid stroke (10 of 759; OR 14·7, 95% CI 7·3-29·5, p<0·0001), particularly during the preceding 2 days (22 of 252 before a vertebrobasilar stroke vs two of 751 before a carotid stroke, OR 35·8, 8·4-153·5, p<0·0001). Of all 59 TNAs preceding (median 4 days, IQR 1-30) vertebrobasilar stroke, only five (8%) fulfilled the National Institute of Neurological Disorders and Stroke (NINDS) criteria for TIA. The other 54 cases were isolated vertigo (n=23), non-NINDS binocular visual disturbance (n=9), vertigo with other non-focal symptoms (n=10), isolated slurred speech, hemisensory tingling, or diplopia (n=8), and non-focal events (n=4). Only 10 (22%) of the 45 patients with isolated brainstem TNAs sought medical attention before the stroke and a vascular cause was suspected by their physician in only one of these cases., Interpretation: In patients with definite vertebrobasilar stroke, preceding transient isolated brainstem symptoms are common, but most symptoms do not satisfy traditional definitions of TIA. More studies of the prognosis of transient isolated brainstem symptoms are required., Funding: Wellcome Trust, UK Medical Research Council, Dunhill Medical Trust, Stroke Association, National Institute for Health Research (NIHR), Thames Valley Primary Care Research Partnership, and the NIHR Biomedical Research Centre, Oxford., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Background and Purpose: The contribution of genetics to stroke risk, and whether this differs for different stroke subtypes, remainsuncertain. Genomewide complex trait analysis allows heritability to be assessed from genomewide association study (GWAS) data. Previous candidate gene studies have identified many associations with stoke but whether these are important requires replication in large independent data sets. GWAS data sets provide a powerful resource to perform replication studies., Methods: We applied genomewide complex trait analysis to a GWAS data set of 3752 ischemic strokes and 5972 controls and determined heritability for all ischemic stroke and the most common subtypes: large-vessel disease, small-vessel disease, and cardioembolic stroke. By systematic review we identified previous candidate gene and GWAS associations with stroke and previous GWAS associations with related cardiovascular phenotypes (myocardial infarction, atrial fibrillation, and carotid intima-media thickness). Fifty associations were identified., Results: For all ischemic stroke, heritability was 37.9%. Heritability varied markedly by stroke subtype being 40.3% for large-vessel disease and 32.6% for cardioembolic but lower for small-vessel disease (16.1%). No previously reported candidate gene was significant after rigorous correction for multiple testing. In contrast, 3 loci from related cardiovascular GWAS studies were significant: PHACTR1 in large-vessel disease (P=2.63e(-6)), PITX2 in cardioembolic stroke (P=4.78e(-8)), and ZFHX3 in cardioembolic stroke (P=5.50e(-7))., Conclusions: There is substantial heritability for ischemic stroke, but this varies for different stroke subtypes. Previous candidate gene associations contribute little to this heritability, but GWAS studies in related cardiovascular phenotypes are identifying robust associations. The heritability data, and data from GWAS, suggest detecting additional associations will depend on careful stroke subtyping.

Objective: Many guidelines recommend emergency assessment for patients with ≥2 TIAs within 7 days, perhaps in recognition of the capsular warning syndrome. However, it is unclear whether all patients with multiple TIAs are at high early risk of stroke and whether treatable underlying pathologies are more prevalent in this group., Methods: We studied clinical characteristics, Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification, and risk of stroke in 1,000 consecutive patients with incident and recurrent TIAs in a prospective, population-based study (Oxford Vascular Study)., Results: Of 1,000 patients with TIAs, 170 had a further TIA within 7 days (105 within 24 hours). Multiple TIAs were not associated with carotid stenosis or atrial fibrillation, and much of the 10.6 (95% confidence interval [CI] 6.5-15.9) risk of stroke during the 7 days after the first TIA was due to patients with small-vessel disease (SVD) etiology (10 of 24 vs 8 of 146, odds ratio [OR] = 12.3, 95% CI 3.7-41.9, p < 0.0001), particularly those with motor weakness (i.e., capsular warning syndrome) compared with hemisensory events (9 of 15 [60%], 95% CI 35.3-84.7 vs 1 of 9 [11.1%], 95% CI 0-31.7, p = 0.03). The 7-day risk of stroke after a recurrent TIA was similar to the risk after a single TIA in patients with non-SVD TIA (8 of 146 [5.5%] vs 76 of 830 [9.2%], OR = 0.58, 95% CI 0.25-1.3, p = 0.20). Of the 9 patients with stroke after a capsular warning syndrome, all had the recurrent TIA within 24 hours after the first TIA, and the subsequent stroke occurred within 72 hours of the second TIA in 8. The ABCD2 scores of all preceding TIAs were ≥4 in all 9 patients with capsular warning syndrome before stroke., Conclusions: Capsular warning syndrome is rare (1.5% of TIA presentations) but has a poor prognosis (7-day stroke risk of 60%). Otherwise, recurrent TIA within 7 days is not associated with a greater stroke risk than that after a single TIA.

Co-localization of GABA and nitric oxide synthase (NOS) has been investigated in neurones in the dorsolateral sector of the periaqueductal grey matter (PAG) in rats. GABA-immunoreactive neurones were found throughout the PAG although their density was greatest in the dorsolateral sector. Neurones containing nicotinamide adenine dinucleotide phosphate-dependent diaphorase, used to indicate NOS, were confined to the dorsolateral sector. GABA immunoreactivity was detected in 26.9% of 3009 diaphorase-reactive neurones counted at all rostro-caudal levels of the PAG in material from three rats. This double-labelled population may act as a neuronal gain control system which sets the level of excitability and responsiveness of effector systems in other sectors of the PAG.

Poxviruses encode a broad range of proteins that interfere with host immune functions such as soluble versions of cytokine receptors. Soluble virus tumour necrosis factor receptors (vTNFRs) were described originally in myxoma and Shope fibroma viruses. Cowpox virus (CPV) encodes three vTNFRs (CrmB, CrmC and CrmD). The genes equivalent to CrmB and CrmC in vaccinia virus (VV) Copenhagen are mutated and are named B28R/C22L and A53R, respectively. CrmD was identified recently in CPV and ectromelia virus but the gene is absent in VV Copenhagen. We have tested for expression of soluble binding activity for human TNF in cultures infected with 18 orthopoxviruses and have found that TNFRs are mostly absent but are produced by VV strains Lister, USSR and Evans, by the CPV elephantpox and by camelpox virus. Interestingly, we also found TNFR activity on the surface of cells infected with VV Lister, USSR and Evans. Sequence analysis of the relevant regions in VV Lister identified an intact A53R gene and an inactive B28R gene. Expression of VV Lister A53R in baculovirus and VV Western Reserve demonstrated that gene A53R encodes an active soluble vTNFR of 22 kDa. Expression and characterization of recombinant vTNFRs from VV Lister (A53R) and CPV (CrmB and CrmC) showed a similar binding specificity, with each receptor binding TNF from man, mouse and rat, but not human lymphotoxin-alpha. Lastly, the VV Lister and CPV vTNFRs bind human TNF with high affinity and prevent the binding of TNF to cellular receptors.

A pilot telepsychiatry session was conducted with the US Department of Defense Satellite Communication System. The subjects were a family incompletely divorced many years before. There were two satellite interviews with this family. Bringing together all members of the original family so that questions could be addressed as to what happened when the children were very young unblocked a 13-year-old communication problem.

We have used Semliki Forest virus (SFV) vectors to express both the human immunodeficiency virus type 1 (HIV-1) envelope precursor gp160 and the cleaved external portion gp120. Expression of the foreign gene in this system is by transfection of recombinant SFV RNA, or by infection with a recombinant SFV virus that has a wide host range. pSFV1-gp120 or pSFV1-gp160 were expressed in baby hamster kidney (BHK) cells and two human cell lines: HeLa cervical carcinoma and MOLT-4 CD4+ T cells. After SFV1-gp120 infection of HeLa cells, 3.3 micrograms of gp120 was secreted into the media by 1 million cells in a 24-hr period. The secreted envelope glycoprotein was recognized by anti-gp120 monoclonal antibodies directed against both linear and conformation-dependent epitopes in different regions of the molecule. The recombinant gp120 also bound to a soluble form of the CD4 receptor. Syncytium formation was observed when MOLT-4 cells were infected with SFV1-gp160. The gp160 expressed by BHK cells induced syncytia during cocultivation with C8166 CD4+ T cells. These data indicate that SFV vectors can be used to produce the HIV-1 envelope glycoproteins to high levels, and that these proteins are correctly processed, folded, and transported to the cell surface. Furthermore, they exhibit functional activity as indicated by their ability to bind to soluble receptor and induce cell-to-cell fusion.

The HTLV-I transcriptional activator tax was used to gain insight into the mechanism of lymphotoxin (LT; TNF-beta) gene induction. Tax-expressing cell lines produce LT biologic activity. An LT promoter (LT-293) CAT construct that contained an NF-kappa B site was active in the LT-producing C81-66-45 cell line, which contains defective HTLV-I but expresses tax. The observation that a mutated LT-kappa B construct (M1-CAT) was inactive in C81-66-45, confirmed the importance of NF-kappa B in LT gene expression. Tax was transfected into HTLV-I-negative human T-cell lines. Jurkat T cells stably expressing tax contained elevated levels of NF-kappa B that directly bound to the LT-kappa B site. Tax co-transfected with reporter constructs into Jurkat cells maximally activated HTLV-I-LTR-CAT and kappa B-fos-CAT and also activated LT-293 to a lesser extent. In JM T cells, tax induced LT-293 activity by two- to four-fold, though there was no induction of M1-CAT. The increase in LT-293 CAT activity mirrored the increase in LT biologic activity seen under these conditions. These studies, the first to demonstrate induction of LT promoter activity over basal levels, indicate that HTLV-I tax causes low-level activation of both endogenous LT and the LT promoter, at least in part through activation of NF-kappa B.

Human T-cell leukemia virus type I (HTLV-I)-infected T-cell lines constitutively produce high levels of biologically active lymphotoxin (LT; tumor necrosis factor-beta) protein and LT mRNA. To understand the regulation of LT transcription by HTLV-I, we analyzed the ability of a series of deletions of the LT promoter to drive the chloramphenicol acetyltransferase (CAT) reporter gene in HTLV-I-positive MT-2 cells. The smallest LT promoter fragment (-140 to +77) that was able to drive CAT activity contained a site that was similar to the immunoglobulin kappa-chain NF-kappa B-binding site. Since the HTLV-I tax gene activates the nuclear form of NF-kappa B, this finding suggested a possible means of HTLV-I activation of LT production. We found that the LT kappa B-like site specifically formed a complex with NF-kappa B-containing nuclear extract from MT-2, C81-66-45, and other activated T cells. Mutation of the LT kappa B site in the context of the LT promoter (-293 to +77) (mutant M1) reduced the ability of the promoter to drive the CAT gene in HTLV-I-infected and noninfected human T-cell lines. These data suggest a general role for NF-kappa B activation in the induction of LT gene transcription. Activation of LT in HTLV-I-infected cells may explain the pathology associated with HTLV-I infection, including the hypercalcemia that is prevalent in adult T-cell leukemia.

This communication describes a technique of stimulated recall and video replay which has reduced the frequency of seizures in five epileptic patients. Each of the patients had long standing partial epilepsy with complex symptomatology of the psychomotor type. It was generally acknowledged that emotional factors played an important role in their poor seizure control. Previous psychotherapeutic efforts had been without benefit because ictal amnesia had erased the memory of the stressful antecedent message-input which had triggered the seizures. Creation of empathetically stressful responses to presentation of audio and video tape recordings of specific problematic social interactions was sufficient to induce seizures in these patients. Video tape recording of the seizure and the antecedant events provided by means by which the patients could acquire otherwise unrecognized or forgotten information. Once equipped with the identity of the specific emotional trigger, the patient could avoid the kinds of events which might be expected to induce a seizure and be better able to cope with threatening environmental cues when encountered in the future.

LT was one of the first lymphokines to be described and has been one of the most difficult to fit into a conceptual framework. Now, 20 years after its discovery, its structure, genetic organization, and linkage are well understood in mouse and human, and insight has been gained into its biological role. It is a T cell-derived glycoprotein of 25 kd coded by a gene within the MHC. It is somewhat (35%) structurally homologous to the macrophage product TNF. The genes for LT and TNF are tightly linked, and the proteins share most biological activities and compete for the same cell surface receptor. LT is induced in an antigen-specific MHC restricted fashion from class I and class II restricted T cells. Viral infection is also associated with LT production by lymphoid cells. LT has several effects on target cells including killing, growth stimulation, and induction of differentiation. The mechanism of LT's effects involves receptor binding and internalization and several sequelae including changes in prostaglandins and chromosome integrity. LT probably plays several biological roles. It can contribute to immunoregulation, defense against viruses, parasitic infections, and rejection of tumors. Understanding LT's role in the pathogenesis of diseases of autoimmunity and immune dysregulation will be the key to devising effective regimens for prophylaxis and treatment.