Plasma quantitation of warfarin and warfarin alcohol by gas chromatography chemical ionization mass spectrometry in patients on warfarin maintenance therapy

A quantitative method has been developed to measure plasma concentrations of warfarin and warfarin alcohol. The analytical procedure uses deuterated analogues as internal standards, and the technique of selected ion monitoring following gas chromatography methane chemical ionization mass spectrometry of the 4'-methyl ethers of warfarin and warfarin alcohol. Concentrations of warfarin and warfarin alcohol have been measured in plasma samples from 43 patients maintained on chronic warfarin therapy and compared with the 'apparent warfarin' concentration as measured by a fluorometric procedure. The study demonstrated a high degree of correlation between the gas chromatography mass spectrometric derived sum of the individual concentrations of warfarin and warfarin alcohol, and the 'apparent warfarin' concentration determined from a spectrofluorometric assay.

Effects of methomyl and ethanol on behavior in the Sprague-Dawley rat

Emotional behavior and activity levels were studied following administration of ethanol and/or a carbamate pesticide, methomyl, to rats via a ground chow diet. Acetylcholinesterase levels were lowered following the experimental diets. The group having the greatest reduction in AChE, the methomyl group, showed less evidence for habituation in an open-field test. No differences relative to control subjects were noted on handling and muricide tests.

Casualty room presentations and schoolboy rugby union

For eight years a casualty station has been operating during competition Rugby Union matches at a large Sydney School. During this time, both diagnosis and treatment have been recorded for every presentation. The casualty station was attended by 556 boys over this period, and approximately 50% of these presentations were for trivial injuries. Forty-three severe injuries occurred, of which most were fractures. The rate of presentation, and the pattern of injury, changed as a greater number of both minor and major injuries than did visitors. There was one injury in boys less than 12 years old, and the greatest incidence of injury was in boys aged from 16 to 18 years. It is concluded that there is a place for casualty services at schoolboy competition games, and that the supervised Rugby Union played in this and comparative school competitions is a reasonably safe game for boys less than 16 years old, to whom issues of schoolboy participation are most applicable.

Nitroblue tetrazolium (NBT) activity in human leucocytes after freezing

Human peripheral blood leucocytes (neutrophil-rich) were collected either with heparin or acid citrate dextrose, frozen with dimethyl sulphoxide at a controlled rate, stored in liquid nitrogen at--196 degrees C and reconstituted with a solution containing dextran. After reconstitution, 20.2% of cells (in absolute numbers 1 in 5 fresh cells) showed a strongly positive nitroblue tetrazolium (NBT) reaction. The quantitative NBT test confirmed the synthesis of formazan/10(6) reconstituted neutrophilsa s15% of the fresh capacity. A slow titration reconstitution method for cells did not improve the functional capacity of thawed leucocytes as judged by the NBT test. When comparing anticoagulants, heparin increased the post-reconstitution cell yields after freezing and increased the absolute number of reconstituted cells capable of developing a positive NBT reaction.

On the use of "calibration equations" in perception research

Gogel's procedure of using "calibration equations" to obtain reports of perceived distance which are at least partially independent of individual differences in response bias, was examined. The procedure involves determining the relationship between reported and physical distances in a full-cue viewing situation. By making four assumptions, this equation can be used to "calibrate" responses gathered from other situations in which perceived distances are under investigation. In the present experiment, both verbal and string-pull measures of perceived distance were obtained for several objects under reduced viewing conditions. Calibration equations were determined for each response measure in a full-cue setting. The usefulness of the calibration technique was tested by comparing the differences between the two response measures for each object seen in reduced viewing, both before and after the application of the calibration procedure. The results indicated that, consistent with the usefulness of the calibration technique, group differences between the measures were almost always decreased by the procedure. However, no general improvement in the agreement of the measures was found when the data were examined on an individual basis. From the results, a modification of the method of calculating calibration equations was suggested that might increase its usefulness by simplifying the arithmetic operations required for the procedure.

The value of the barium enema in the diagnosis of acute appendicitis

Contrary to popular belief, the barium enema is a safe diagnostic tool in the management of acute appendicitis. This is a survey of our experience over three years with 489 cases of suspected acute appendicitis. Two hundred eighteen barium enema examinations were done. The barium enema has a high degree of pathological correlation (97.14%). It has reduced negative surgical exploration in women between 11 and 40 years of age. This group traditionally represents the greatest diagnostic challenge in appendicitis. As a result, our negative exploration rate has been reduced to a figure below the average for this disease. We recommend its performance in all patients who pose a diagnostic dilemma.

Medical aspects of surfcraft usage

A prospective study of one year's duration on surfcraft-associated injuries recorded 399 injuries. The incidence and pattern observed was significantly different from results gathered in the same area five years earlier. The frequency of injury was found not to have increased as much as would have been expected from the increased popularity of board riding. The pattern of injury was also shown to have altered. It is concluded that, while occasional severe injuries occur, the use of surfcraft, particularly surfboards, constitutes a relatively risk-free sport.

The use of banked autologous blood in total hip replacement surgery

Fifty patients anticipating total hip replacement, with an average age of 63, donated 125 units of blood in an organized autologous transfusion program. All but 3 patients demonstrated the ability to respond to oral iron and maintain adequate hemoglobin levels for subsequent phlebotomies. No complications were encountered and the program was well received by the participating patients. The advantages of autologous transfusion are numerous, including the avoidance of the risk of serum hepatitis, blood reactions, blood incompatibilities. Autologous transfusion constitutes a source of blood availability in the elective procedure of total hip replacement. This procedure is safe, practical and well tolerated.

The specificity of anti-galactocerebroside antibody and its reaction with lysolecithin-solubilized myelin

Antibody to galactocerebroside can be produced in rabbits by the injection of the hapten together with a carrier protein (GC.BSA) or by immunization with the myelin fraction of brain homogenates (GC.M). The anti-galactocerebroside activity of both sera is mainly directed towards the galactose moiety of the galactolipid. In a complement fixation system they react with galactocerebroside (galactosylceramide) and monogalactosyldiglyceride, but not with glucocerebroside (glucosylceramide).

Passive cutaneous anaphylaxis can be elicited by the carrier, but not the hapten. There is no demonstrable reaction to the glycolipid itself—even when tested in association with auxiliary lipids or the carrier protein; or as a component of solubilized myelin.

The specificity of antibody to galactocerebroside appears to be unaffected by the nature of the carrier or associated proteins. This is shown by the fact that antisera to GC.BSA and GC.M react in an identical fashion with the lipid—protein complexes formed when myelin is solubilized with lysolecithin. Complement fixation is increased by solubilization, but increasing the lysolecithin/myelin ratio above the minimum necessary to render myelin completely soluble decreased the specific activity. Following isopycnic centrifugation maximum complement fixing activity was present in a fraction having a density of 1.04 at 10°, corresponding to one of three peaks of galactocerebroside concentration. However, precipitin reactions were obtained over a range of fractions of higher density.

These results suggest that galactocerebroside is present in myelin in at least two forms and provides further confirmation of the fact that this hapten is responsible for a large part of the organ-specific complement fixing and precipitating activity of anti-myelin serum.