An evaluation of the gum elastic bougie

This study was designed to evaluate the routine use of a gum elastic bougie for tracheal intubation. The median time to intubation with the gum elastic bougie while simulating an 'epiglottis only' view was only 10 s longer than the time taken during conventional intubation with an optimum view. Three of the patients required a gum elastic bougie-assisted intubation after attempts at conventional visual intubation had failed. There was no significant difference in the incidence of postoperative sore throat and hoarseness between the two groups. We recommend that anaesthetists should use the gum elastic bougie whenever a good view of the glottis is not immediately obtained.     

Identification of Babesia bigemina infected erythrocyte surface antigens containing epitopes conserved among strains

The presence of previously uncharacterized antigens (new antigens) on the surface of intact erythrocytes infected with three strains of Babesia bigemina from Kenya and one each from Puerto Rico, Mexico, St. Croix, and Texcoco-Mexico was demonstrated by indirect immunofluorescent antibody (IFA) reactions. These antigens were not strain specific because antibodies in bovine immune serum to either the Mexico or Kenya isolates reacted with all seven strains tested. Homologous and heterologous immune serum antibodies bound a maximum of 83% and 55%, respectively, of intact erythrocytes infected with the Kenya-Ngong strain but not uninfected erythrocytes. Both sera caused agglutination of only infected erythrocytes. Antibodies eluted from the surface of glutaraldehyde (0.25%) fixed infected erythrocytes had IFA reaction patterns among strains similar to those of immune sera before elation. Eluted antibodies were used to determine if these antigens were protein and encoded by B. bigemina. Eluted antibodies bound seven parasite-encoded proteins of 240, 220, 66, 62, 58, 52 and 38 kDa in an erythrocyte surfacespecific immunoprecipitation reaction of ³⁵-methionine labelled proteins. It was concluded that the surface of B. bigemina infected erythrocytes had parasite-encoded proteins and that these proteins had surface exposed epitopes that were conserved among the seven strains examined which were from two continents.     

A 90-Day Inhalation Toxicity Study of Raw Shale Oil in Fischer 344 Rats

A 90-Day Inhalation Toxicity Study of Raw Shale Oil in Fischer344 Rats. GORDON T., STROTHER, D. E., CRAMER, D. V., AND GOODE,J. W. (1987). Fundam. Appl. Pharmacol. 9, 287–296. Thepotential health effects of a raw shale oil were evaluated ina 90-day inhalation study in Fischer 344 rats. Groups of 15male and 15 female rats were exposed 6 hr/day, 5 days/week for13 weeks to aerosol concentrations of 0, 56, 120, or 492 mg/m³.In the high-dose group, 10 males and 7 females died prior tothe termination of the study, most within the first 5 weeksof the experiment. A dose-dependent suppression in weight gainwas seen in all of the shale oil-exposed groups. The failureto gain weight was associated with a variety of clinicopathologicabnormalities, including a dose-related decrease in red andwhite blood cells, with lowered plasma protein levels and increasedserum alkaline phosphatase, and with total bilirubin levelsin males. The exposure of the test animals to aerosolized rawshale oil was also associated with inflammatory and hyperplasticlesions in the lungs and upper respiratory tract, atrophy ofthe thyrnus and thymic-dependent portions of the peripherallymphoid system, and bone marrow. These changes demonstratethat inhalation of raw shale oil aerosol can produce major organtoxicity similar to that found after exposure to other unrefinedoil products.     

A Comparison of the Acute Toxicity, Neuropathology, and Electrophysiology of N,N-Diethyl-m-toluamide and N,N-Dimethyl-2,2-diphenylacetamide in Rats

The insect repellent DEET and the structurally related herbicidediphenamid both cause ataxia associated with a spongiform myelinopathylargely confined to the cerebellar roof nuclei. This local myelinopathywas accompanied by the formation of neuronal cytoplasmic cleftsand was produced by a single dose of 1 to 3 g/kg N,N-diethyl-m-toluamide(DEET). These dose levels also produced a severe and often fatalprostration and clear electrophysiological signs of prolongedsuppressed seizure activity. Diphenamid produced an identicalmyelinopathy after doses of 0.8 to 1.5 g/kg but without thesevere prostration, suppressed seizures, or neuronal clefts.The effects of diphenamid were shown to be reversible over 3to 7 days by neuropathological, motor, and auditory evoked responseindices. Both compounds caused characteristic changes in auditoryevoked response which may be useful in clinical diagnosis. Sixother alkyl amides, two of which produce signs of CNS excitation,failed to produce myelinopathy at the maximum tolerated doses.Our findings show close parallels with a number of human casesof DEET poisoning and indicate that other amides, like diphenamid,also pose a potential hazard.     

Technical Grade but Not Recrystallized {alpha}-Naphthylthiourea Potentiates Superoxide Release by Rat Neutrophils Stimulated in Vitro by Phorbol Myristate Acetate

Technical Grade but Not Recrystallized -Naphthylthiourea PotentiatesSuperoxide Release by Rat Neutrophils Stimulated in VitrobyPhorbol Myristate Acetate. ROTH, R.A., AND BALL, T.M. (1986).Fundam. Appl. Toxicol. 7, 324–328. -Naphthylthiourea (ANTU)causes pulmonary edema and pleural effusion in rats. It hasbeen suggested that ANTU pneumotoxicity may be mediated by bloodneutrophils (PMNs) via the release of reactive oxygen species.Accordingly, we tested the effect of technical grade ANTU (tANTU)on the ability of rat peritoneal PMNs to release superoxide(O₂). tANTU did not itself stimulate O₂ production by PMNs,but it increased the O₂ released in response to PMN stimulationby phorbol myristate acetate (PMA). This effect was dependentupon the amount of tANTU added. In PMNs activated in vitro bya submaximal PMA stimulus, addition of 20 µg/ml tANTUdoubled superoxide release. When tANTU was recrystallized fromethanol, the purified ANTU was not effective in potentiatingthe effect of PMA on PMNs. This suggests that an impurity intechnical grade ANTU is capable of increasing O₂ release bystimulated PMNs. tANTU and recrystallized ANTU caused similarpneumotoxicity in rats in vivo, suggesting that the unidentifiedimpurity does not markedly influence the biologic effects ofANTU.     

Treatment of refractory fludarabine induced autoimmune haemolytic with the anti‐cd20 monoclonal antibody rituximab

A patient with cold‐type autoimmune haemolytic anaemia for 8 years developed progressive B cell chronic lymphocytic leukaemia (CLL). Despite the risk of fludarabine induced exacerbation of haemolysis, he was given aggressive anti‐CLL therapy with six courses of FCR (fludarabine 25 mg/m² D1–3, cyclophosphamide 250 mg/m² D2–4 and rituximab 375 mg/m² D1) every 4 weeks. This resulted in a marked acute increase in haemolysis shortly after completing each course of fludarabine. However, haemolysis had settled to its baseline level by the time of subsequent courses of FCR. FCR resulted in complete clinical remission of CLL but residual haemolysis persisted. The patient was then given four weekly infusions of single agent rituximab, resulting in ongoing remission of haemolysis. In this patient, rituximab appears to have controlled fludarabine induced exacerbation of autoimmune haemolysis. In addition, subsequent single agent rituximab therapy resulted in prolonged remission of cold‐type autioimmune haemolytic anaemia. It remains to be seen if the addition of rituximab will allow other patients with a positive direct Coomb's test and/or autoimmune haemolysis to receive fludarabine containing chemotherapy without undue risk of life‐threatening haemolytic anaemia.     

Functional Electrical Stimulation: An Overview

The development of future neural prostheses involves much more than connecting commercially available stimulators to disabled individuals. Safe and effective operation of prostheses requires fundamental studies of the electrode-tissue interface. The electrochemistry of the interface must be controlled to prevent toxic byproducts. Histopathological studies of stimulated tissue are necessary to establish safe limits of stimulation and to determine mechanisms of neural damage when it does occur. Electrophysiological studies elucidate which neural pathways are excited and help in the design of more selective electrode arrays. Biomaterials are required that protect the implant from the hostile environment of the body. Presently available materials are being improved and totally new materials are being developed. One of the goals of neural prostheses developers is a nonhermetic packaging material that can be applied to miniature implants without appreciably increasing their size. The techniques used to make integrated circuits on silicone substrates are ideally suited to making ultraminiature electrodes with self-contained electronic signal processing. Both integrated circuit stimulating and recording electrodes are being designed and fabricated.     

The SdaBlood Group Antigen in Tissues and Body Fluids

Abstract. In man the Sd^aantigen is present in most secretions with the greatest concentration in urine. There is little difference in the amount of Sd^asubstance in the urine of newborn infants, pregnant women and normal adults but there is a much greater amount in the saliva of newborn infants than in adults. Approximately half the people whose red cells group as Sd(a-) secrete Sd^asubstance in the urine. Anti-Sd^aantibody is present in 50% of Sd(a-) non-secretors of Sd^asubstance, though most of these antibodies only react with the strongest Sd(a +) cells. The greatest Sd^aactivity has been found in human meconium, guinea pig urine and guinea pig kidney. Activity can be detected in the urine of many animal species. The kidneys of 5 bird species did not contain Sd^a.