Event-related potential indices of semantic priming using masked and unmasked words: evidence that the N400 does not reflect a post-lexical process

Several authors have contended that the N400 is a reflection of a post-lexical event such as that proposed by Neely and Keefe [J.H. Neely, D.E. Keefe, Semantic context effects on visual word processing: a hybrid prospective/retrospective processing theory, in: G.H. Bower (Ed.), The Psychology of Learning and Motivation: Advances in Research and Theory, Vol. 23, Academic Press, New York, 1989, pp. 207-248.], whereby the subject compares the word on the current trial to the "context" provided by the word on the preceding trial [M. Besson, M. Kutas, The many facets of repetition: A cued-recall and event-related potential analysis of repeating words in same versus different sentence contexts, Journal of Experimental Psychology: Learning, Memory and Cognition, 19 (5) (1993), 1115-1133; C. Brown, P. Hagoort, The processing nature of the N400: Evidence from masked priming. Journal of Cognitive Neuroscience, 5(1) (1993), 34-44; P.J. Holcomb, Semantic priming and stimulus degradation: Implications for the role of the N400 in language processing, Psychophysiology 30 (1993), 47-61; M.D. Rugg, M.C. Doyle, Event-related potentials and stimulus repetition in indirect and direct tests of memory, in: H. Heinze, T. Munte, G.R. Mangun (Eds), Cognitive Electrophysiology, Birkhauser Boston, Cambridge, MA, 1994]. A study which used masked primes to directly test this possibility has been reported by Brown and Hagoort [C. Brown, P. Hagoort, The processing nature of the N400: evidence from masked priming. Journal of Cognitive Neuroscience, 5(1) (1993), 34-44]. When the primes were masked, no priming effect was observed on the N400. When behavioral data were collected in the same paradigm, from another group of subjects, the usual priming effect on RT was obtained. Considered together, the data from the two groups of subjects indicated that activation of semantic representations had occurred without conscious awareness. As no N400 priming effect was observed, it was suggested that N400 must reflect a post-lexical process. This interpretation, however, is at odds with the findings of other studies which have reported N400 priming effects under conditions where post-lexical processes would not be thought to operate[J. Anderson, P. Holcomb, Auditory and visual semantic priming using different stimulus onset asynchronies: an event-related brain potential study. Psychophysiology 32 (1995), 177-190; J. Boddy, Event-related potentials in chronometric analysis of primed word recognition with different stimulus onset asynchronies, Psychophysiology 23 (1986), 232-245; D. Deacon, T. Uhm, W. Ritter, S. Hewitt, The lifetime of automatic priming effects may exceed two seconds, Cognitive Brain Research 7 (1999), 465-472; P.J. Holcomb, Automatic and attentional process: an event-related brain potential analysis of semantic priming. Brain and Language 35 (1998) 66-85]. The present study replicated Brown and Hagoort using a repeated measures design, a shorter SOA (stimulus onset asynchrony), and a slightly different threshold setting procedure. Significant priming effects were obtained on the mean amplitude of the N400 regardless of whether the words were masked or unmasked. The findings imply that the processing subserving the N400 is not postlexical, since the N400 was manipulated without the subjects being aware of the identity of the words.

Malignant ascites as only manifestation of metastatic prostate cancer

Prostate cancer is the most common malignancy in men in the US. Both at diagnosis and throughout the disease progression it can metastasize to multiple organs (bone and lymph being the most common). Effusions (either pleural or abdominal) are relatively uncommon, but usually occur as a result of soft tissue lesions. Herein we report on a patient with androgen independent prostate cancer and an elevated PSA with disease confined to ascites of the abdomen.

Permethrin-treated chaddars and top-sheets: appropriate technology for protection against malaria in Afghanistan and other complex emergencies

Insecticide-treated mosquito nets (ITN) provide excellent protection against malaria; however, they have a number of shortcomings that are particularly evident in politically unstable countries or countries at war: not everyone at risk can necessarily afford a net, nets may be difficult to obtain or import, nets may not be suitable for migrants or refugees sleeping under tents or plastic shelter. There is a need to develop cheaper, locally appropriate alternatives for the most impoverished and for victims of complex emergencies. Afghan women, in common with many Muslim peoples of Asia, wear a veil or wrap known as a chaddar to cover the head and upper body. This cloth doubles as a sheet at night, when they are used by both sexes. A randomized controlled trial was undertaken in which 10% of the families of an Afghan refugee camp (population 3950) in north-western Pakistan had their chaddars and top-sheets treated with permethrin insecticide at a dosage of 1 g/m2 while a further 10% had their chaddars treated with placebo formulation. Malaria episodes were recorded by passive case detection at the camp's health centre. From August to November the odds of having a falciparum or vivax malaria episode were reduced by 64% in children aged 0-10 years and by 38% in refugees aged < 20 years in the group using permethrin-treated chaddars and top-sheets. Incidence in refugees over 20 years of age was not significantly reduced. The cost of the permethrin treatment per person protected (US$0.17) was similar to that for treating bednets (and cost only 10-20% of the price of a new bednet). An entomological study simulating real-life conditions indicated that host-seeking mosquitoes were up to 70% less successful at feeding on men sleeping under treated chaddars and some were killed by the insecticide. Permethrin-treated top-sheets and blankets should provide appropriate and effective protection from malaria in complex emergencies. In Islamic and non-Islamic countries in Asia, treated chaddars and top-sheets should offer a satisfactory solution for the most vulnerable who cannot afford treated nets.

Control of zoophilic malaria vectors by applying pyrethroid insecticides to cattle

The principal method of malaria control in South and West Asia--indoor residual spraying--is extravagant with insecticide. A more efficient way of deploying insecticide might be to apply it on livestock since the malaria vectors in the region are highly zoophilic. A series of investigations assessed the potential of cattle treated with pyrethroid to control zoophilic mosquitoes. Permethrin, deltamethrin, and lambdacyhalothrin were applied to cattle using a sponge at concentrations of 0.5 g/m2, 0.025 g/m2, and 0.025 g/m2, respectively. 'Whole animal' insecticide bioassays that simulated natural mosquito-host contact were used to measure insecticidal and behavioural effects on wild host-seeking mosquitoes. The bioassays were performed on both sheltered and outdoor grazing animals for up to 45 days post-treatment. The possibility that treatments might cause diversion of host-seeking vectors from cattle to people nearby was also investigated. At the doses tested deltamethrin had the most pronounced and longest-lasting effect, reducing the proportion of bloodfed survivors by over 50% for the first two weeks. The majority of mosquitoes affected by the insecticide were killed before feeding. Insecticidal impact was generally lower on grazing than on sheltered animals. There was no diversion of host-seeking mosquitoes from treated cattle to nearby humans at any stage after treatment. The application of insecticide to livestock using a campaign approach may prove an effective means of controlling malaria in the region. At the doses tested deltamethrin is the most appropriate insecticide for this purpose.

The lifetime of automatic semantic priming effects may exceed two seconds

The N400 component of event-related potentials (ERPs) was obtained in a modified version of the Neely [J.H. Neely, Semantic priming and retrieval from lexical memory: Roles of inhibitionless spreading activation and limited-capacity attention, Journal of Experimental Psychology: General, Vol. 106 (1977), pp. 226-254.] paradigm which permits unconfounding of semantic priming effects due to automatic and attentional processes. It was found that a short stimulus onset asynchrony (SOA) of 250 ms between the prime and the target was associated with automatic but not expectancy effects on the amplitude of N400. At a long SOA of 2000 ms between prime and target, semantic priming effects on N400 were obtained associated with both automatic and expectancy processes. Moreover, there was no significance difference in the magnitude of the automatic effects at the two SOAs, suggesting that automatic processing had not decayed within the 2000 ms interval between the prime and target. The results support the two-processing interpretation of semantic priming advanced by Posner and Synder [M.I. Posner, C.R.R. Snyder, Attention and cognitive control, in: R.L. Solso (Ed.), Information Processing and Cognition: The Loyola Symposium, Erlbaum, Hillsdale, NJ (1975).] and concur with the results of Neely [J.H. Neely, Semantic priming and retrieval from lexical memory: Roles of inhibitionless spreading activation and limited-capacity attention, Journal of Experimental Psychology: General, Vol. 106 (1977), pp. 226-254], with the exception of indicating a longer persistence of automatic processes.

Anthroponotic cutaneous leishmaniasis in Kabul, Afghanistan: vertical distribution of cases in apartment blocks

Owing to the civil war, the inhabitants of Kabul in Afghanistan are suffering a major epidemic of anthroponotic cutaneous leishmaniasis (ACL) caused by Leishmania tropica. Surveys conducted among children in 2 high-rise apartment blocks in the city revealed that the prevalence of active lesions was much lower on upper stories: 84% lower in one block (chi 2 = 7.13, d.f. = 1, P = 0.008) and 54% lower in the other (chi 2 = 6.17, d.f. = 1, P = 0.01). Similar trends were apparent with regard to scars from old lesions. These results suggest that in Kabul most transmission of ACL takes place in the home. In addition, the results imply that there must be limited vertical movement of the vector within apartment blocks. Together, these findings suggest that indoor spraying should be an effective means of control and that insecticidal applications could probably be restricted to lower stories.

Assessing the performance of anti-vibration gloves--a possible alternative to ISO 10819, 1996

Special gloves (commonly referred to as anti-vibration gloves) have been offered for many years as personal protection against hand-arm vibration generated, for example, by powered hand tools. An internationally agreed means of quantifying the vibration-reducing performance of such gloves was not available until the publication of International Standard ISO 10819, 1996. The evaluation of the Standard reported here has led to the conclusion that the test could be improved to give more information to the potential glove user about how the glove might perform. Investigations of the main factors which can influence the results of glove transmissibility tests have formed the basis for a proposal to develop the Standard. The proposed alternative test measures the performance of a glove in octave bands and the resultant data can be used to estimate the potential that the glove has to protect against any given vibration source. Examples of the application of the proposed alternative test for selection of anti-vibration gloves matched to particular vibration sources (powered hand tools) are given. The advantages and disadvantages of the two test methods are discussed. The evaluation of the Standard and proposals for its development are under discussion with members of the committee which developed ISO 10819, 1996.

Event-related potential indices of semantic priming following an unrelated intervening item

Interposing an unrelated word between related primes and targets often disrupts priming. This finding has been used to support the view that semantic information is represented in a distributed fashion, rather than locally. In some studies where unrelated items intervened between the prime and target, however, significant priming was nevertheless obtained. The discrepant results of these studies has been attributed to differences in speed-accuracy tradeoff, post-lexical checking, conscious rehearsal of the prime and differences in the depth to which the prime and target were processed. The present study was designed in such a way as to minimize variability associated with post-lexical influences. The N400 component of the human event-related potential was used as a physiological index of the extent to which priming occurred with and without the interposition of an unrelated item. Priming effects on both the amplitude and latency of the N400 were rendered non-significant by the presence of an intervening unrelated word. The results are interpreted as tentative evidence that semantic representations are distributed.

Resistance of falciparum malaria to chloroquine and sulfadoxine-pyrimethamine in Afghan refugee settlements in western Pakistan: surveys by the general health services using a simplified in vivo test

Surveys of drug resistant falciparum malaria were conducted in several Afghan refugee settlements, distributed over a 700 km range in western Pakistan, during the transmission seasons of 1994 and 1995. Symptomatic malaria patients were recruited by a process of passive case detection at the refugees' basic health units. To facilitate follow-up by local health workers, a modified version of the WHO extended in vivo test was adopted in which blood smears were taken from each subject, and clinical symptoms recorded, at weekly intervals. Resistance to chloroquine and sulfadoxine-pyrimethamine was identified in every settlement. The frequency of chloroquine resistance ranged from 18% to 62%. Resistance occurred mostly as RI, with RII resistance never exceeding 11%. Resistance to sulfadoxine-pyrimethamine occurred at much lower frequencies, ranging from 4% to 25%. There was a resumption of clinical symptoms at the onset of parasite recrudescence in over 90% of cases. The policy of using chloroquine as first-line treatment might be changed in favour of sulfadoxine-pyrimethamine in most camps and areas of western Pakistan. The modified in vivo test was almost as accurate as the normal WHO in vivo test in identifying the grade of resistance, and should prove a useful tool for the monitoring of resistance to common antimalarials by district health services.

Chloroquine resistance in Pakistan and the upsurge of falciparum malaria in Pakistani and Afghan refugee populations

Surveys conducted in Pakistan during the last decade show that falciparum malaria has become resistant to chloroquine in Pakistani and Afghan refugee populations throughout the country. Although RI resistance is common everywhere (with a frequency of 30%-84%), RII is rarer (2%-36%), and RIII resistance has yet to be detected. The national policy is to prescribe chloroquine as first-line treatment of malaria. A repeated in-vivo survey in a sentinel village indicated that prescription of chloroquine can lead to a 15% increase in the frequency of resistance in a single year, and similar trends were observed in other districts. Coinciding with the spread of resistance is a 6-fold increase in the number of falciparum cases recorded nationally between 1982 and 1992 and a parallel, 5-fold increase in the number of cases recorded in the Afghan refugee population. Resistance contributes to this trend in various ways. Firstly, patients with resistant malaria make repeated visits to health centres. In the sentinel village, for example, where resistance was measured at 71%, recrudescent infections inflated by 66% the genuine incidence of new infections recorded at the health centre. Secondly, owing to ineffective treatment, resistant infections are often still patent during the post-transmission season. This may enlarge the 'overwintering' parasite reservoir, leading to a surge of new cases when transmission resumes. Other factors potentially contributing to the upsurge in falciparum include the decrease availability of insecticide for indoor spraying. Despite the problems posed by resistance for case management, the evidence from the vector-control programme among the refugees is that malaria control through well-targeted campaigns of insecticide spraying is still able to reduce the incidence of falciparum malaria to a level that existed before the advent of resistance.

[Cardiovascular risk factors in persons aged 40-42 years in the county of Hedmark 1988-94]

We present the results from three surveys conducted in 1988, 1991 and 1994 in Hedmark comparing risk factors for cardiovascular disease among men and women age 40-42 years. The data are compared with the results for persons in the same age group from the counties Vestfold, Rogaland and Nordland, and examined in the same periods. In 1991 the average levels of total cholesterol and infarction risk score were the same in Hedmark and the three other counties, but in 1994 Hedmark compared less favourably. While the mean levels of total cholesterol showed minimal difference between rural and urban municipalities in Hedmark, triglycerides and systolic blood pressure were higher in the rural areas. Adjustment of the results in Hedmark for lower attendance rate among unmarried, divorced and widowed persons in 1991 and 1994 than in 1988 does not affect other risk factors than smoking. We discuss possible explanations of the less favourable results and the implications for primary prevention of cardiovascular diseases.

Transmission and control of vivax malaria in Afghan refugee settlements in Pakistan

Regular biting collections were conducted in 1993-1994 to investigate seasonal fluctuations in the abundance of anophelines in Afghan refugee villages in north-western Pakistan. Enzyme-linked immunosorbent assay were used to test heads-plus-thoraces for the presence of malaria sporozoites. Anophelines giving positive results for Plasmodium vivax were captured in every month except January. Nine species were positive. Biting rates showed a marked increase in May, after the spring rains, and thus spring transmission of vivax malaria seems certain. However, transmission of vivax malaria reached its peak only after the monsoon in July. To determine the optimal time to control vivax malaria by indoor spraying with residual insecticide, spray campaigns were conducted in either spring or summer in 14 refugee villages. Villages sprayed in July 1994 showed a mean reduction in annual incidence of 62% (95% confidence interval [CI] +/-6%) relative to the previous year, whereas villages sprayed in April 1994 showed only a 15% reduction (95% CI +/- 32%). Parasite prevalence surveys conducted in April and October 1994 confirmed the greater efficacy of spray campaigns waged in July. The insecticide malathion proved as effective as the pyrethroid lambdacyhalothrin, even though several species of anopheline were resistant to malathion.

Sustainability of pyrethroid-impregnated bednets for malaria control in Afghan communities

Between 1992 and 1995 a series of studies was undertaken to assess the long-term suitability of pyrethroid-impregnated bednets (PIBs) for malaria control in Afghan refugee communities in two villages in North-West Frontier Province, Pakistan. During 1992, 86% of bednet owners volunteered to have their bednets re-impregnated, and a further 15% of families purchased nets at two-thirds of cost price. From 1992 onwards, 27% of the villagers returned to Afghanistan, and annual house spraying campaigns were introduced to protect those still resident but sleeping without bednets. Within 3 years, these campaigns, together with PIBs, reduced the annual incidence of malaria by 87%, from 597 to 78 cases per 1000 population. Nevertheless, 65% of resident families continued to re-impregnate their nets annually with permethrin. To assess whether PIBs were still being used and were still protective, in view of these reduced transmission rates, we carried out a case--control study in 1994 on febrile or otherwise symptomatic patients presenting at village health centres. Comparison of the slide-positivity rates of PIB users and those without bednets showed that regular usage reduced the odds of contracting falciparum and vivax malaria to 0.22 (95% confidence interval (CI): 0.09-0.55) and 0.31 (95% CI: 0.19-0.51), respectively. There was no evidence of a sex- or age-bias in bednet use or in protective effect. The results indicate that a community-based PIB programme is an appropriate malaria control measure in areas where management or security problems make traditional house-spraying campaigns impossible. A relevant finding for those involved in the monitoring of bednet distribution projects is that the local coverage of bednets and the local impact on malaria, even when introduced to remote areas, can be estimated very cheaply by health centre microscopists who simply catalogue blood film diagnoses according to patients' bednet use practices.

Emergency medicine at a large rock festival

The organisation of on-site medical personnel and facilities is described for an open air rock concert attended by 62,000 people. Care of the majority of patients was completed on site, avoiding an increased workload for local hospitals and general practitioners. Many of the head injuries could have been avoided by preventing the distribution of promotional items and large drinks containers which were thrown as missiles.

[Development of risk factors for cardiovascular diseases among persons aged 40-42 years in the county of Finnmark 1973-93]

During the period 1973-1993, the National Health Screening Service carried out five screenings of risk factors for cardiovascular disease among 40-42 years of age in the county of Finnmark. Risk for myocardial infarction has decreased, mainly due to reductions in total cholesterol, which fell by more than 10% in both sexes from 1973-74 to 1993. Cholesterol levels now seem to be stabilizing. Considerably fewer persons smoked daily in 1977-78 than in 1973-74. From 1977-78 to 1993, little change occurred among men, but the percentage of women who smoked daily increased by 10%. Systolic and diastolic blood pressure were slightly higher in 1993 than in 1990. Since 1987-88 consumption of butter and of traditionally made coffee (boiled, not filtered) has decreased. Compared with other counties, Finnmark shows high values for cholesterol, smoking habits and "boiled" coffee. Preventive measures still have a potential to influence the future trend.

Pyrethroid-sprayed tents for malaria control: an entomological evaluation in Pakistan

Field trials were undertaken in the North West Frontier Province of Pakistan to determine the effects of pyrethroid-sprayed tents on feeding success, mortality and biting-rates of wild mosquitoes attracted to bait cows confined within the tents. Under natural conditions, endophagic mosquitoes rested only briefly in untreated tents during the night, followed by complete exodus at dawn. In tents sprayed on the interior surface with permethrin 0.5 mg/m2 or with deltamethrin 0.03 g/m2 the biting rate of Anopheles stephensi was reduced by about 40%; deterrency against culicines and other anophelines was much less. Mortality-rates of bloodfed mosquitoes from the treated tents were 75% An.stephensi, 65% An.subpictus but only 10% of culicines. Outer fly-sheets prolonged the effective life of the treatment; bioassays on the sprayed inner-sheets showed that insecticidal efficacy remained high for over a year, whereas on tents without fly-sheets permethrin residual efficacy declined rapidly 20-40 weeks post-treatment. It is concluded that tent-spraying with fast-acting photostable residual pyrethroid insecticide would probably provide effective protection against malaria transmission for the inhabitants of tents in any part of the world where the vector mosquitoes are endophilic and susceptible to pyrethroids.

An entomological investigation of the likely impact of cattle ownership on malaria in an Afghan refugee camp in the North West Frontier Province of Pakistan

Field trials were undertaken to determine the effect of close proximity of humans to livestock on the human biting rates exhibited by various anophelines. The results indicate that proximity to cattle and to goats increases the subject's chances of being bitten by anophelines. Man-biting by Anopheles stephensi rose by 38% (8-68% CI) in the presence of a cow, and by 50% (16-84% CI) in the presence of two goats. Other species exhibited similar trends. These findings explain the results of an earlier trial which revealed that malaria prevalence was higher amongst families that kept cattle than those that did not. The findings are discussed in relation to existing information regarding the host preferences of local anophelines and classic theories regarding zooprophylaxis. Our findings suggest that animals are only likely to have a worthwhile prophylactic affect when the vector is zoophilic, and then only when the animals are deployed to form a barrier between that vector and man. In situations where deployment of livestock to form a zoobarrier is impractical, the livestock should be located as far from man as possible.

Hepatitis B immunisation status of A&E healthcare workers

Hepatitis B immunisation has still not been taken up by all 'at risk' healthcare workers, even though it remains a significant occupational hazard. Angela Dancocks and Susanne Hewitt's research in an Accident and Emergency Department highlights the need for better information to ensure uptake and questions the current definition of those 'at risk'.

A phase II evaluation of cisplatin, bleomycin, and mitomycin-C in patients with recurrent squamous cell carcinoma of the cervix

Cisplatin, bleomycin, and mitomycin-C were used to treat 25 patients with recurrent squamous cell carcinoma of the cervix. Six patients had a partial response, yielding a total response rate of 27%. Nine patients had stable disease. The median survival for the whole group was 30 weeks. The median survival for responders was 32 weeks. The median progression free interval for the whole group was 12 weeks and the median progression-free free interval for responders was 14 weeks. The toxicities noted were primarily nausea, vomiting, and myelosuppression. The combination of cisplatin, bleomycin, and mitomycin-C has modest effectiveness in the treatment of recurrent squamous cell carcinoma of the cervix, but represents no improvement over single-agent chemotherapy.

Red cell autoantibodies, multiple immunoglobulin classes, and autoimmune hemolysis

The effects and interrelationships of multiple immunoglobulin coating (i.e., increased red cell [RBC]-bound IgM and/or IgA in addition to IgG) were investigated in 404 patients with warm-reactive RBC autoantibodies on 590 occasions. Multiple immunoglobulins were detected by enzyme-linked direct antiglobulin tests in 218 samples (37%), but in only 87 (15%) by agglutination methods. Differences in populations were examined by chi-square, with p less than 0.005 being required for significance because of the multiple tests. Compared with IgG coating alone, multiple immunoglobulins were significantly associated with larger quantities (greater than 800 molecules/RBC) of IgG, multiple IgG subclasses, IgG3 and C3d bound to the cells, and with serum haptoglobin levels of less than 0.1 g per L. The latter association was still significant when higher levels of RBC-bound IgG and subclass pattern were taken into account. In samples with multiple immunoglobulin coating, there was no significant relationship (p greater than 0.05) between haptoglobins of less than 0.1 g per L and either C3d or multiple IgG subclasses. It was concluded that multiple immunoglobulin coating, even when undetected by agglutination methods, is a major cause of hemolysis: it is part of a more generalized autoimmune response and acts with other factors such as the quantity of bound IgG, the IgG subclass pattern, and complement; it also has an important hemolytic effect in its own right.

Erythrocyte autoantibodies, subclasses of IgG and autoimmune haemolysis

The subclass pattern of red cell bound IgG autoantibody was studied in 304 patients on 426 occasions. Subclass interrelationships with time, other cell bound immunoglobulins (IgM, IgA), amount of bound IgG and serum haptoglobin levels were investigated using population proportions; because of the multiple statistical tests, P less than 0.01 was required for significance. IgG1 was most common, being found in 98% of cases and as the sole subclass in 64%; multiple subclasses occurred in 34.5%. The IgG subclass pattern possibly changed with time (P less than 0.02, greater than 0.01), populations being compared at 6 and 12 months. There was a highly significant and important correlation between multiple IgG subclasses and multiple immunoglobulin coating; in our further studies, this necessitated the use of samples where only cell bound IgG was increased. Multiple IgG subclasses strongly correlated with larger amounts of cell bound IgG, groups with greater than 2 and less than 1 OD units by the enzyme-linked direct antiglobulin test being compared (approximately greater than 800 and less than 400 molecules IgG per red cell respectively). Multiple subclasses (P less than 0.05, greater than 0.01), but not IgG3, were possibly associated with low haptoglobin levels; significance was reached, however, if the multiple immunoglobulin effect was ignored. IgG subclass interrelationships are clearly complex and require strictly defined populations for their study.

Erythrocyte autoantibodies, autoimmune haemolysis, and myelodysplastic syndromes

Immunohaematological investigations were carried out in 46 patients with erythrocyte autoantibodies associated with myelodysplastic syndromes. Eight patients had refractory anaemia, 17 refractory anaemia with ring sideroblasts, 11 refractory anaemia with excess of blasts, four chronic myelomonocytic leukaemia, five refractory anaemia with excess of blasts in transformation and one could not be classified. Standard agglutination direct antiglobulin tests showed that the red cells were most often coated with IgG and C3d, though increased amounts of IgM or IgA were also found in 15 of 35 cases (43%) when the more sensitive enzyme linked method was used. The IgG antibodies were predominantly of IgG1 subclass. Clinically important autoimmune haemolysis occurred in 15 patients, and was of "warm", "cold," and "mixed" types in seven, four, and four cases, respectively: it is important to recognise its presence in view of the good response to treatment. The increased incidence of erythrocyte autoantibodies in myelodysplastic syndromes is thought to be one manifestation of disturbed immune homeostasis.

Concomitant radiation therapy and chemotherapy in the treatment of advanced squamous carcinoma of the lower female genital tract

Twenty-three consecutive patients with advanced squamous carcinoma of the lower female genital tract were entered into a pilot study to determine the response rate and toxicity of a combination of intravenous cisplatin and 5-fluorouracil given concomitantly with radiation therapy. Twenty (87%) of the patients had a complete clinical response. Two patients (9%) had a partial response and one (4%) had stable disease. Nine (45%) of the complete responders have recurred with a median time to recurrence of 4 months. Seven (35%) had some component of local recurrence. The complete responders who have not recurred have been followed a median of 17 months. The acute toxicity was generally mild and there was no life-threatening acute complications. Three patients developed significant late complications. The response rate in this study was very high. The responses were usually prompt and dramatic, but often not sustained.

Wound hematoma: prophylaxis with topical thrombin

We studied 123 patients having elective exploratory laparotomy through a midline vertical incision for gynecologic disease; patients were randomized to receive wound irrigation with either saline or topical thrombin before closure of the incision. Seven patients were not evaluable. No patient received low-dose heparin therapy perioperatively. No patient in either group had a clinically significant wound hematoma or disruption. Minor wound hematomas were more common in the saline group, a finding that approached statistical significance. Blood coagulation profiles were not different in the two groups either preoperatively or postoperatively. Topical thrombin is probably not clinically useful in preventing wound hematomas in patients who do not receive perioperative treatment with low-dose heparin; however, it seems to be safe for application to open wounds.

Leuprolide acetate in the treatment of refractory or persistent epithelial ovarian cancer

Leuprolide acetate (Lupron, TAP Pharmaceuticals, North Chicago), a gonadotropin-releasing hormone analogue, was administered subcutaneously at a 1-mg dose for a minimum of 8 weeks to 23 patients with refractory epithelial ovarian cancer. Eighteen of these patients were evaluable. There were no complete responses. Four patients (17%) had a partial response, with a median duration of 52 weeks. Three of six patients with grade 1 carcinomas had a partial response and two had stabilized disease. There was only one response among 15 patients with grade 2 or 3 disease. Therapy was well tolerated, with three patients complaining of hot flashes and two of mild pedal edema. Leuprolide acetate thus shows evidence of antitumor activity against refractory grade 1 epithelial adenocarcinoma of the ovary. Further trials with larger numbers of patients should be conducted.

Patients with red cell autoantibodies: selection of blood for transfusion

The provision of blood for transfusing patients whose sera contain red cell autoantibodies requires considerable expertise. Over 8 years, 3888 samples from 2149 patients were examined; the varying clinical presentation necessitated a flexible investigative approach. The autoantibodies showed evidence of blood group specificity in 706 patients (32.9%), usually within the Rh system for warm reacting antibodies, whereas cold antibodies were mostly anti-I. Concomitant alloantibodies were detected by noting varying reaction strengths during antibody investigation and compatibility testing, and by absorption techniques using autologous or selected allogenous red cells. Alloantibodies were found in 294 patients (13.7%); the most frequent were anti-E and anti-K. Compatibility tests were performed on SAG-M donor blood of suitable ABO group, similar Rh genotype, Kell negative and lacking antigens to any alloantibodies detected. All units of blood were incompatible by at least one technique and were issued as 'not compatible but considered suitable'. A total of 7052 units was issued for 1685 patients; no haemolytic reactions were reported. It was concluded that blood can be safely given to patients with autoantibodies, even in serologically complex cases, providing adequate investigations are carried out.

An enzyme-linked direct antiglobulin test for assessing erythrocyte bound immunoglobulins

An enzyme-linked direct antiglobulin test (DAGT) for assessing erythrocyte-bound IgG, IgM and IgA is described. The test is carried out in microtitre plates using heavy chain-specific, alkaline phosphatase-linked, goat anti-human globulin reagents with p-nitrophenyl phosphate as substrate. Results are expressed in optical density (OD) units per 3.6 X 10(7) red cells. The method is reproducible, with coefficients of variation of 0.056, 0.093 and 0.087 for IgG, IgM and IgA respectively. The linear relationship between the amount of red cell-bound antibody and the OD reading for each immunoglobulin class shows that the method is suitable for quantitative studies. Healthy individuals were found to have small amounts of immunoglobulin bound to their red cells with mean values of 0.251, 0.087 and 0.128 OD units per 3.6 X 10(7) red cells for IgG, IgM and IgA respectively; there was no difference between male and female subjects. In the clinical situation, the enzyme-linked DAGT was considered to show significantly increased amounts of cell-bound immunoglobulin when the results were more than three standard deviations above the mean and the quantitative results permitted an accurate assessment of the progress and response to treatment of patients with autoimmune haemolysis.

Major morbidity after pelvic exenteration: a seven-year experience

Thirty-eight patients underwent pelvic exenteration at the University of South Florida during the last seven years. The majority of the operations were performed for recurrent carcinoma of the cervix, and the operative mortality was 5.3%. Twenty-one patients developed major morbidity in the postoperative period, and 11 with complications involving the gastrointestinal or urinary tract required reoperation. Multivariate logistic regression analysis demonstrated a correlation between the amount of pelvic radiation, type of pelvic floor, type of pelvic drain, amount of blood loss, race, and the occurrence of serious postoperative morbidity. Strategies to avoid serious postoperative morbidity are discussed.

Small quantities of erythrocyte bound immunoglobulins and autoimmune haemolysis

Enzyme linked and radioimmune direct antiglobulin tests (DAGTs) were used to assess red cell bound IgG, IgA, and IgM in 585 patients referred to an immunohaematology reference centre. One hundred and fifty eight patients with less than or equal to 200 mol IgG and small amounts of IgA and IgM coating their red cells were studied in detail. The presence of autoimmune haemolysis was determined from the clinical, haematological, and biochemical findings; it occurred in at least 25% of the 158 patients, the degree varying widely. There was a highly significant association between small increases in cell bound immunoglobulins and the presence of autoimmune haemolysis. Immunoglobulins of IgG, IgA, and IgM classes could produce autoimmune haemolysis when the classical agglutination DAGTs were negative; the IgA and IgM were usually found in association with IgG. The haemolytic effect was enhanced by the presence of complement and combinations of immunoglobulin classes on the red cells.

Conduction tissue in the transplanted human heart

Eleven orthotopically transplanted human hearts have been examined at retransplantation or necropsy. They were selected to cover the period up to 3 years after transplantation. The recipient SA node was examined in six, the donor SA node in eight and the AV conduction tissue in all eleven. Each of these areas has been examined by serial sectioning. All the conduction tissue is discretely involved in rejection and this involvement is no more severe than in the adjacent myocardium. In the AV tissue there is a tendency for the peripheral parts to be more frequently involved than the proximal. There is little evidence of permanent structural damage to the AV tissues by recurrent episodes of mild to moderate rejection. In the atrial nodes there is about a 50 per cent chance of surgical or procurement damage to both the recipient and the donor tissue.

Enzyme linked direct antiglobulin tests in patients with autoimmune haemolysis

Enzyme linked and agglutination direct antiglobulin tests were carried out on blood samples from 219 patients suspected of having autoimmune haemolysis. The enzyme linked tests were more sensitive: they could detect the small amounts of IgG, IgA, and IgM which are normally present on red cells and showed increased amounts of cell bound immunoglobulins in patients with Coombs test negative autoimmune haemolysis. Many patients had immunoglobulins of more than one class bound to their red cells; considering the degree of haemolysis in individual patients, it appeared that the different immunoglobulin classes acted synergistically in effecting red cell destruction, even in amounts too small to be detected by the agglutination tests. In patients with cold reacting autoantibodies and complement coating of the red cells active haemolysis was found (with one exception) where IgM was detected on the cells by the enzyme linked method. Elution studies indicated that immunoglobulins detected just by the enzyme linked techniques were red cell antibodies. Both enzyme linked and agglutination tests were negative in 66 patients: 61 of these had no evidence of haemolysis, and in the other five the haemolysis was not autoimmune in origin.

Effect of blood on the activity and persistence of antigen induced inflammation in the rat air pouch

The hypothesis that haem iron derived from synovial microbleeding has a proinflammatory effect on the synovial membrane was tested by adding autologous whole blood and fractions derived from it to a naturally remitting rat air pouch model of allergic inflammation. The induction of such a subcutaneous air pouch produces a cavity lined by mesenchymal cells comparable to the synovial membrane. Autologous whole blood was found to prolong a low grade inflammatory state, this effect being attributable to a red cell component, most probably haem iron. Whole blood in the absence of an inflammatory stimulus does not have this effect, indicating that the mechanism is one of prolonging or promoting existing allergic inflammation, rather than inducing an inflammatory response.

Adenine nucleotide concentrations in patients with erythrocyte autoantibodies

Erythrocyte adenine nucleotide concentrations were measured in 154 patients with erythrocyte autoantibodies and 811 normal subjects using a luciferin-luciferase bioluminescent assay. The patients were initially divided into haemolysing and non-haemolysing groups. Red cell adenosine triphosphate (ATP) concentrations were significantly raised in the 96 patients with active haemolysis compared with the normal subjects and with the 58 patients in the non-haemolysing group. Although the patients categorised as non-haemolysing had higher ATP values than the normal subjects, this was because several patients had the anaemia of chronic disorders, which is associated with a shortened red cell life. Measurement of red cell ATP was a useful indicator of mean erythrocyte age and a raised value in patients with erythrocyte autoantibodies reflected active haemolysis.

Autoimmune hemolysis: a critical review

Autoimmune hemolysis is defined as a shortening of erythrocyte lifespan due to antibodies directed against the individuals own red cells. This autoantibody production (by B lymphocytes) is thought to result from deficient activity of suppressor T lymphocytes. The rate of erythrocyte destruction depends on the properties of the autoantibodies and on the activities of the complement and mononuclear phagocyte systems: anemia results when destruction outweighs marrow production. Autoimmune hemolysis, which may be primary or secondary, is classified into "warm," "cold," and "mixed" types. The hemolysis associated with pregnancy. Donath-Landsteiner antibodies, of mixed type, and in children, is treated in detail. Current treatment is with immunosuppressive drugs, surgery, and plasma exchange, though immunomanipulation may become important in the future; blood transfusion may be a life-saving adjunct to other therapy.

Paroxysmal nocturnal haemoglobinuria. A clinicopathological study of 26 cases

26 patients, 13 male and 13 female, with paroxysmal nocturnal haemoglobinuria (PNH) are described. The diagnosis was based on the finding of a positive Ham's test. PNH developed in 4 patients with aplastic anaemia, and 3 patients with established PNH developed marrow hypoplasia during the course of the disease. In 2 cases autoimmune haemolysis was also present; this association has not been described previously. The majority of patients presented with anaemia and dark urine, or with evidence of thrombosis. A high index of suspicion was needed to avoid missing the diagnosis. Haemolytic crises were usually precipitated by infection, and renal failure requiring dialysis sometimes resulted; a positive direct antiglobulin test was often found at times of increased haemolysis. Thromboses were the most frequent complication, and when intra-abdominal vessels were affected, pain was particularly troublesome. The disease had a widely variable course; 4 patients made a complete recovery and 10 died, 8 from thrombotic complications and 2 from infections associated with marrow hypoplasia. Survival ranged from 1 year to 30 years and the median survival in those who died was 3.5 years.