Hyperglycaemia and mortality from acute stroke

Hyperglycaemia has been observed after acute stroke, and isassociated with a poor prognosis. It is not known whether thisis due to the stress response of the acute illness or whetherhyperglycaemia is, in itself, harmful to ischaemic nervous tissue.Seventy-one patients admitted to hospital with acute strokeand no history of diabetes or other acute illness were recruited,and fasting blood sampling was carried out within 24 h of symptomonset, for plasma glucose and stress hormones and levels ofhaemoglobin A1c (HbA1c). Computerized tomography of the brainwas carried out on 77% of the subjects. The subjects were followedup for 3 months or until death. Glucose levels were higher insubjects who died during the course of the study (p=0.025),but this relationship became non-significant after age (p<0.001) and cortisol (p= 0.001) levels were taken into accountwith multivariate analysis. The correlation between serum cortisoland the volume of the lesion on CT scan was also stronger thanthe relation of glucose with volume. Haemoglobin A1c had norelationship with either mortality or lesion volume. These findingssuggest that the hyperglycaemia seen after an acute stroke issecondary to a stress response and they do not support the theoryof hyperglycaemia being harmful to ischaemic nervous tissue.These findings have implications for the treatment of acutestroke with hypoglycaemic agents.     

Antibody-Dependent Cell-Mediated Cytotoxicity in the Mouse

The surface characteristics of the mouse spleen cells mediating antibody-dependent cytotoxicity (ADCC) against antigen-coated chicken erythrocytes have been studied by several different column fractionation methods The major effector cells in this system were shown to be surface-adherent and could be depleted from spleen cells by passage through glass-bead ovalbumin/anti-OA immune complex columns (Fc receptor-binding), glass-bead immunoglobulin/anti-mouse Ig columns (Fc receptor and surface immunoglobulin-binding), and glass-bead mouse Ig/rabbit (Fab')₂-anti-mouse Ig or Sephadex G-200/rabbit anti-mouse Ig columns (surface immunoglobulin binding) The concentration of EDTA in the medium used to fractionate the cells played a significant role in determining whether surface immunoglobulin could be demonstrated on the ADCC effector cells. From these results, the conclusion was drawn that ADCC on the part of mouse spleen cells could be mediated by surface-adherent, Fc receptor-positive cells bearing surface immunoglobulin of unknown origin. The possibility that ADCC can be mediated by a heterogenous population of cells in the mouse spleen is discussed.     

HELICOBACTER PYLORI-SPECIFIC TUMOUR-INFILTRATING T CELLS PROVIDE CONTACT DEPENDENT HELP FOR THE GROWTH OF MALIGNANT B CELLS IN LOW-GRADE GASTRIC LYMPHOMA OF MUCOSA-ASSOCIATED LYMPHOID TISSUE

Previous studies have shown that tumour cells from low-grade B-cell gastric lymphomas of mucosa-associated lymphoid tissue (MALT) type proliferate in vitro in response to heat-killed whole cell preparations of Helicobacter pylori , but only in the presence of tumour-infiltrating T cells. This response is strain-specific in that the tumours studied responded optimally to different strains of H. pylori . It was unclear from these studies, however, whether the ability to recognize the specific stimulating strains of H. pylori was a property of the tumour cells or the tumour-infiltrating T cells. This study shows that whereas the tumour cells do not respond to H. pylori , both freshly isolated tumour-infiltrating T cells and a T cell line derived from these cells proliferate in response to stimulating strains of H. pylori . T cells from the spleen of one of the patients do not share this property. These results suggest that B-cell proliferation in cases of low-grade gastric lymphoma of MALT type in vitro in response to H. pylori is due to recognition of H. pylori by tumour-infiltrating T cells, which in turn provide help for tumour cell proliferation. The observations provide an explanation for properties of gastric MALT-type lymphoma, such as regression following eradication of H. pylori and the tendency of the tumour to remain localized to the primary site.     

Scheduled napping as a countermeasure to sleepiness in air traffic controllers

The aims of this study were to measure sleep during a planned nap on the night shift; and to use objective measures of performance and alertness to compare the effects of the nap opportunity versus staying awake. Twenty-eight air traffic controllers (mean age 36 years, nine women) completed four night shifts (two with early starts and two with late starts). Each type of night shift (early/late start) included a 40-min planned nap opportunity on one occasion and no nap on the other. Polysomnographic data were used to measure sleep and waking alertness [spectral power in the electroencephalogram (EEG) during the last hour of the night shift and the occurrence of slow rolling eye movements (SEMs) subsequent to the nap]. Psychomotor performance task [Psychomotor Vigilance Task (PVT)] was completed at the beginning and end of the shift, and after the nap (or an equivalent time if no nap was taken). Nap sleep latencies were relatively long (mean = 19 min) and total sleep time short (mean = 18 min), with minimal slow wave sleep (SWS, mean = 0%), and no rapid eye movement sleep. Nap sleep resulted in improved PVT performance (mean and slowest 10% of reaction time events), decreased spectral power in the EEG and reduced the likelihood of SEMs. The occurrence of SWS in the nap decreased spectral power in the EEG. This study indicates that although sleep taken at work is likely to be short and of poor quality it still results in an improvement in objective measures of alertness and performance.     

MORBIDITY IN MINOR GYNAECOLOGICAL SURGERY: A COMPARISON OF HALOTHANE, ENFLURANE AND ISOFLURANE

A comparison was made between halothane, enflurane and isofluranewith regard to their suitability for minor gynaecological proceduresin patients who would be leaving the hospital within 24 h ofthe anaesthetic. Seventy-five healthy patients were randomlyallotted to one of three groups which received one of theteanaesthetics. In respect of patient acceptance and postoperativemorbidity there were no significant differences between halothaneand enflurane, but after isoflurane there was a significantlygreater frequency of minor sequelae (headache, nausea, dizzinessand coughing) and its pungent odour made it unacceptable tosome patients.     

Anti-inflammatory effects of a new tumour necrosis factor-alpha (TNF-α) inhibitor (CNI-1493) in collagen-induced arthritis (CIA) in rats

A recently developed compound, a multivalent guanylhydrazone (CNI-1493) that inhibits TNF-α production by suppressing TNF-α translational efficiency, was administered in an experimental model of collagen type II-induced arthritis in DA rats. CNI-1493 was injected daily intraperitoneally either before the onset of arthritis or after the establishment of clinical disease. Prophylactic treatment with CNI-1493 significantly prevented or delayed the onset and suppressed the severity of arthritis in a dose-dependent manner. Therapeutic intervention with CNI-1493 in established joint disease also resulted in a significant reduction of clinical signs of arthritis in treated animals. No severe side-effects were noted when animals were treated with daily CNI-1493 doses up to 5 mg/kg. An immunohistochemical study was performed which demonstrated that CNI-1493 led to a reduced expression of TNF-α at the site of disease activity. Thus, CNI-1493 with documented inhibitory effects on TNF-α synthesis, has proven successful in ameliorating the course of arthritis in CIA. We believe that the use of a compound such as CNI-1493 with a defined mode of action provides a useful tool for dissecting and understanding important pathogenic mechanisms operating in the development of chronic arthritis.