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Cyclic GMP and cyclic AMP levels in eight different rat tissues were examined after animlas were immersed in liquid nitrogen. In order of decreasing concentration, cerebellu, kidney, lung and cerebral cortex contained the greatest quantities fo cyclic GMP. These tissues also contained relatively high concentrations of cyclic AMP. Compared to values in animals which were sacrificed in liquid nitrogen, levels of both nucleotides in many of the tissues examined were altered by decapitation or anesthesia with ether and pentobarbital. Decapitation increased the levels of both cyclic GMP and cyclic AMP in cerebellum, lung, heart, liver and skeletabl muscle. However, decapitation increased only cyclic AMP in cerebral cortex and kidney. Our previously reported high level of cyclic GMP in lung was attributed to ether anesthesia and surgical removal which increased the cyclic GMP content in lung, heart, testis and skeletal muscle. The effect of ether on cyclic GMP levels in lung and heart was blocked by pretreatment of animals with atropine which indicated that cholinergic agents increase cyclic GMP content in these tissues. Acetylcholine and carbachol in the presence of theophylline increased the accumulation of cyclic GMP in incubations of rat lung minces. Increases in cyclic GMP and cyclic AMP levels in cerebellum with ether anesthesia were prevented if rats were immersed in liquid nitrogen after anesthesis with ether. Anesthesia with pentobarbital decreased the levels of cyclic GMP in cerebellum and kidney and increased the nucleotide in heart, liver, testis and skeletal muscle compared to levels in tissues from animals immersed in liquid nitrogen. However, pentobarbital increased cyclic AMP levels in cerebellum and cerebral cortex and decreased the nucleotide in liver, kidney, testis and skeletal muscle. These studies provide a possible explanation for the variability in in vivo levels of cyclic GMP and cyclic AMP which have been previously reported. In addition, these studies support the hypothesis that the synthesis and degradation of cyclic AMP and cyclic GMP are regulated independently and not necessarily in a parallel or reciprocal manner. These studies also suggest that the increase accumulation of one cyclic nucleotide has no major effect on the synthesis and/or metabolism of the other; however, such interactions cannot be entirely excluded from the results of this study.

A radioimmunoassay was developed to measure the levels of oestrone and oestradiol in 0.5–1.0 ml of domestic fowl peripheral plasma. The oestrogens were extracted with diethyl ether, chromatographed on columns of Sephadex LH-20 and assayed with an antiserum prepared against oestradiol-17β-succinyl-bovine serum albumin using a 17 h incubation at 4°C. The specificity, sensitivity, precision and accuracy of the assays were satisfactory. Oestrogen concentrations were determined in the plasma of birds in various reproductive states. In laying hens the ranges of oestrone and oestradiol were 12–190 pg/ml and 29–327 pg/ml respectively. Levels in immature birds, in adult cockerels and in an ovariectomized hen were barely detectable. The mean concentrations of oestrone and oestradiol in the plasma of four non-laying hens (55 pg/ml and 72 pg/ml respectively) and one partially ovariectomized hen (71 pg/ml and 134 pg/ml respectively) were well within the range for laying hens. It is evident that the large, yolk-filled follicles are not the only source of oestrogens in the chicken ovary.

A new method has been developed for measuring virtually continuous distributions of ventilation-perfusion ratios (V(A)/Q) based on the steadystate elimination of six gases of different solubilities. The method is applied here to 12 normal subjects, aged 21-60. In nine, the distributions were compared breathing air and 100% oxygen, while in the remaining three, effects of changes in posture were examined. In four young semirecumbent subjects (ages 21-24) the distributions of blood flow and ventilation with respect to V(A)/Q were virtually log-normal with little dispersion (mean log standard deviations 0.43 and 0.35, respectively). The 95.5% range of both blood flow and ventilation was from V(A)/Q ratios of 0.3-2.1, and there was no intrapulmonary shunt (V(A)/Q of 0). On breathing oxygen, a shunt developed in three of these subjects, the mean value being 0.5% of the cardiac output. The five older subjects (ages 39-60) had broader distributions (mean log standard deviations, 0.76 and 0.44) containing areas with V(A)/Q ratios in the range 0.01-0.1 in three subjects. As for the young subjects, there was no shunt breathing air, but all five developed a shunt breathing oxygen (mean value 3.2%), and in one the value was 10.7%. Postural changes were generally those expected from the known effects of gravity, with more ventilation to high V(A)/Q areas when the subjects were erect than supine. Measurements of the shunt while breathing oxygen, the Bohr CO(2) dead space, and the alveolar-arterial oxygen difference were all consistent with the observed distributions. Since the method involves only a short infusion of dissolved inert gases, sampling of arterial blood and expired gas, and measurement of cardiac output and minute ventilation, we conclude that it is well suited to the investigation of pulmonary gas exchange in man.

Adaptation to a repeated stress in male rats was studied by measuring plasma ACTH by radioimmunoassay 2.5 min or plasma corticosterone by acid fluorescence 20 min alter initiation of the stress. No adaptation was seen in the secretion of ACTH in response to ether, tourniquet, or leg-break stresses repeated at 90 min intervals 1–3 times. A marked rise in plasma ACTH concentration was produced within 2.5 min after application of each stress. Plasma ACTH always returned to basal levels by 90 rain after application of stress. Ether stress repeated at 24-hr intervals for 3 days did not produce any decrease in either the plasna ACTH or corticosterone response by the third day. These data indicate that no adaptation in ACTH secretion in response to repeated stress occurs under the conditions of our experiments.

Rats were injected i.p. with pentobarbitone sodium 40 mg/kg or were exposed to diethyl ether anaesthesia for 15 to 60 min. Monoamine synthesis in vivo was measured in various brain regions by determining the accumulation of dopa and 5-hydroxytryptophan (5-HTP) during 15 or 30 min after the i.p. injection of NSD 1015 (3-hydroxybenzylhydrazine HCl, 100 mg/kg), an inhibitor of the aromatic amino acid decarboxylase. Pentobarbitone retarded the formation of dopa and 5-HTP by about 25% in most brain regions but had no effect on striatal dopa formation. Ether accelerated the formation of dopa and 5-HTP in most brain regions, the action on striatal dopa being most pronounced (to 250% of control). The effect was generally somewhat less marked during the second than during the first half-hour of anaesthesia. A postanaesthetic inhibition of dopa formation was found in the striatum and of 5-HTP formation in whole brain. If hypothermia was allowed to develop, the stimulating action of ether on dopa and 5-HTP formation tended to be partly antagonized. A complex interaction between NSD 1015 and the hypothermic response to ether was observed.

1 The effect of the ether anaesthesia on the plasma half-life of N-(2 hydroxy ethyl) 2-phenyl ethyl carbamate has been studied in rats. 2 The plasma half-life of the carbamate was considerably shorter in animals anaesthetized with ether prior to drug administration than in control rats. 3 The longer plasma half-life of the carbamate in control animals was shown to be due to enterohepatic circulation. 4 Inhibition of this phenomenon by ether was responsible for the shorter plasma half-life of the carbamate in animals anaesthetized with this agent before drug administration. 5 The possible mechanisms by which the ether-induced effect is brought about are discussed.

Summary. By means of an embryo culture technique, it was shown that vitamin E has a direct action, without recourse to the maternal metabolism, in maintaining embryonic growth. The action of N,N'\x=req-\ diphenyl-p-phenylenediamine in vitro was similar to that of vitamin E but ethoxyquin was inactive; the results were similar to those previously obtained in vivo by other workers with these two antioxidants. The implications of these data on the theories of the biological function of vitamin E are discussed.

The effect of ether on peripheral serum levels of prolactin(PRLN), luteinizing hormone (LH), and follicle stimulating hormone (FSH) was investigated during the late afternoon of proestrus or diestrus

Fish meals and fish flour with low oil content were artificially infected with Salmonella oranienburg. In nine trials the effect of moisture content, temperature, atmospheric oxygen content, addition of an antioxidant, ethoxyquin (EQ) and of some short chain unsaturated organic acids, crude fish oil, a highly unsaturated fraction of fish oil, the free fatty acids derived from this fraction and of different extracts of fish meals on the death rate of Salmonella, was studied. Elevated temperature (30 oC), an oxygen atmosphere and material containing highly unsaturated oils or fatty acids accelerated Salmonella death rate. EQ was shown not to have a bactericidal action and when added in conjunction with highly unsaturated oil or fatty acids counteracted the bactericidal effect of these materials. A high death rate seemed to accompany active oxidation in the test media.

The addition of halothane, methoxyflurane, or enflurane to hepatic microsomes caused the appearance of a trough at 420 mμ and simultaneous appearance of an absorption band at 385 mμ (type I), indicative of an interaction between cytochrome P-450 and the anesthetics. Diethyl ether had no effect Halot

Several enzymes of the Embden-Myerhof pathway were found, in vitro, to be insensitive to high concentrations of halothane. However, glutamate dehydrogenase was inhibited in vitro in a dose-dependent manner by methoxyflurane, trichloroethylene, diethyl ether and halothane in concentrations greater than those used in clinical practice. This allosteric enzyme is believed to be involved with central nervous transmission. The inhibition of activity was immediate and reversible with all the agents investigated. In the presence of halothane, enzyme kinetic experiments demonstrated that the inhibition was of the non-competitive type thus suggesting that anaesthetic agents induced conformational changes in the glutamate dehydrogenase molecule.

In order to study the effect of the thiamine derivative O, S-dicarbethoxythiamine (DCET) on kanamycin (KM) ototoxicity, electrophysiological and phase contrast microscopical studies were carried out u

Tryptophan hydroxylase activity in the midbrain of the rat increases as a consequence of electric foot shock, ether anesthesia, and cold exposure, all of which elevate plasma corticosterone levels. Bilateral adrenalectomy prevents this stress-induced increase in enzyme activity. Tryptophan hydroxylase activity and plasma corticosterone are both elevated at 6 p.m. compared to 8 a.m. Administration of corticosterone increases tryptophan hydroxylase activity in normal rats. Parachlorophenylalanine inhibits the stress-induced tryptophan hydroxylase activity. Tryptophan was found not to be directly involved in the stimulation of tryptophan hydroxylase activity but may be involved in the depression of tryptophan hydroxylase activity. Evidence is provided for suspecting that the serotonin neuronal system and the pituitary-adrenal endocrine system may participate in a reciprocal control loop.

The crystal structure of a triclinic form of the copper(II) complex of 3-ethoxy-2-oxobutyraldehyde bis(thiosemicarbazone) (CuKTS) has been determined. The KTS coordinates to copper(II) as a tetradentate ligand via two nitrogen and two sulphur atoms. The unit cell is triclinic, space group P 1 , with dimensions a = 9.306(6), b = 10.443(7), c = 7.479(5) A, α = 90.63(5), β = 114.25(5), γ = 98.42(5)°, observed density 1.720 g.cm−1, calculated density 1.721 g.cm−1, Z = 2. The structure was refined by full-matrix least-squares methods with anisotropic temperature parameters for non-hydrogen atoms to R = 0.056 for 2454 reflections. The ethoxyethyl side chain is disordered. The molecules pack in sheets, but the hydrogen bonding is generally weak. In the crystal structure, sulphur atoms in adjacent molecules lie above and below the copper atom of a central molecule, completing coordination about the Cu(II) with two long CuS distances of 3.101(2) and 3.312(2) A. These values may be compared to the molecular plane CuS bond lengths of 2.263(1) and 2.267(1) A and CuN bond lengths of 1.980(2) and 1.959(2) A. Thus there are potential binding sites in the axial positions of the copper atom. Binding at at least one of these sites probably occurs when the complex is carrying out its biological function, during which it is believed to act on a thiol group.

A patient who had eosinophilia and striking granulomatous pulmonary vasculitis is reported. The vasculitis was limited to muscular pulmonary arteries and was accompanied by a giant-cell reaction and dense infiltrates of eosinophils. The bronchi showed changes characteristic of allergic asthma. This entity is related to the spectrum of diseases regarded generally as the hypereosinophilic syndromes. The presence of pulmonary vasculitis, however, adds considerable prognostic and therapeutic significance.

Methods for determining the chemical dose of ethyl methanesulfonate (EMS) to the DNA of mouse spermatozoa in the vasa deferentia and epididymides have been developed. These include procedures for the removal of contaminating protamine, which, like DNA, possesses nucleophilic sites that can be ethylated by EMS. At least 99% of all sperm protamine (at a 95% confidence level), as well as any other cellular contaminants, is removed during purification of the DNA. The purified DNA recovered from spermatozoa gives no indication of a preferential recovery of either (G+C)-rich or (A+T)-rich regions of the mouse genome: the [ 14 C]dT/[ 3 H]dC ratios for whole sperm and sperm DNA were the same for each animal tested. The spermatozoa of males used in the dosimetry studies were labeled with [ 14 C]thymidine, and then the animals were given various [ 3 H]EMS doses intraperitoneally. A constant exposure time of 4 h was used. The ratios of 3 H and 14 C activities in whole sperm and purified sperm DNA were used to measure the percentage of the total sperm ethylation occurring in the DNA. The maximum percentage found was about 18% in the dose range of 100–400 mg/kg. Values for the ethylations per nucleotide ( E / N ) ranged from ∼ 10 −7 at 3.3 mg/kg up to ∼ 10 −4 at 400 mg/kg, and the data indicated that E / N increased with the 1.5 power of the dose. E / N was also measured in testicular DNA, and the values obtained were close to those found for spermatozoan DNA. The results of such chemical dosimetry studies will be far-reaching in the interpretation of molecular events responsible for genetic alterations. As an example, dominant lethal studies by others, using EMS in the dose range considered in the present paper, have shown little or no effect until two or more days after injection of the mutagen into male mice. Since many sperm DNA ethylations are found after a 4-h exposure to EMS it appears that most of these DNA ethylations are not genetically important, at least in the production of dominant lethals, and that perhaps genetic damage occurs only at rarely ethylated DNA sites.

Ethoxyquin (6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline) was administered to rats at a dose level of 0.5 per cent in the diet for 14 days. It caused a marked increase in liver weight and induction of microsomal drug metabolizing enzymes. In contrast glucose-6-phosphatase activity was depressed. During a 30-day recovery period after removal of ethoxyquin the following parameters were monitored at intervals of 0, 3, 7, 14 and 30 days: liver weight, microsomal protein, cytochrome P-450, cytochrome b 5 , biphenyl-4-hydroxylase, ethylmorphine-N-demethylase, glucose-6-phosphatase and DNA. Recovery appeared to be biphasic, specific enzyme activity and DNA concentration returning to normal in 3–7 days but, as a result of the slower return to normal liver size, total hepatic enzyme activity did not return to control levels until the 30th day.

Serum prolactin levels following ether anesthesia and laparotomy were measured in intact, cyclic rats which were injected daily, beginning on the first day of diestrus, with either oil or with 2 (P2) or 10 mg (P10) of progesterone. A single P2 or P10 injection affected neither the basal (decapitation) nor the ether-laparotomy serum prolactin level. Six days of treatment, however, reduced the ether-laparotomy-induced in-crease in the prolactin level, but had no effect on the basal level. Ovariectomized rats were also injected daily for 6 days, beginning on the 14th post-castration day, with either oil, P10,0.01 (E 0.01) or 0.25 µg (E 0.25) of free estradiol, or a combination of either E 0.01 + P10 or E 0.25 + P10. No significant differences in the serum prolactin levels were found between the rats killed by decapitation and those subjected to ether-laparotomy in any of these groups. Treatment with P10, however, significantly lowered the serum prolactin level although treatment with E 0.25 raised it. P10 treatment also reduced the estrogen (E O.25)-stimulated elevation in the prolactin level.

SUMMARY Plasma prolactin was measured by double antibody radioimmunoassay in ovariectomized rats bearing indwelling aortic catheters. Samples were obtained during recovery from ovariectomy and catheterization, at various times during the day, after blood volume reduction, and after administration of various anaesthetics. Prolactin levels were stabilized by day 3 after the operation but not by day 1. There was a significant (P < 0·01) increase in plasma prolactin during the afternoon in both ovariectomized rats and ovariectomized rats treated with 1 mg polyoestradiol phosphate. The magnitude of the response was more pronounced in the animals treated with oestrogen. Withdrawal of blood samples without subsequent replacement of fluid volume induced a significant (P < 0·05) decrease in plasma prolactin concentration after removal of only 1·2 ml blood within 20 min. No change was observed, however, when blood was replaced with saline. Ether and the intraperitoneal injection of sodium pentobarbitone produced prolonged increases in plasma prolactin whereas the intra-arterial administration of sodium pentobarbitone produced no change. Urethane and chloral hydrate caused only transient increases in plasma levels of prolactin regardless of the route of administration. Ketamine did not significantly alter plasma levels of prolactin.

The effect of 6 inhalational anaesthetics on speed of swimming (produced by ciliary movement) has been studied in Tetrahymena pyriformis. There was no evidence of stimulation at low dose levels and higher levels caused rapid, reversible, dose-dependent reduction in swimming velocity. The concentrations of anaesthetics which depressed motility by 50% were of the same order as those required for anaesthesia in mammals, except in the case of cyclopropane, for which the required level was 4 times higher than the anaesthetic level. Correlation with lipid solubility was not as close as is the case for narcotic concentration. Oxygen consumption was reduced with increasing amounts of halothane in parallel with the reduction in swimming velocity. Halothane produced deciliation of Tetrahymena at about 10 times the anaesthetic dose for man; regrowth of cilia took place within 4 h of withdrawal of the drug. There were no changes in the ultrastructure of the cilia, basal bodies and associated microtubular systems at levels of halothane sufficient to stop cilial beat. At higher concentrations deciliation occurred immediately distal to the axosome and there was variable swelling of the mitochondria.

Whatever steroids are involved in the pathogenesis of adrenal-regeneration hypertension (ARH), cholesterol side-chain cleavage (SCC) activity is a prerequisite for their synthesis. Both cholesterol SCC and 11β-hydroxylase activities were compared in our experiments. By combining the use of cyanoketone, a 3β-ol dehydrogenase inhibitor, with a sensitive radioimmunoassayfor pregnenolone, we were able to measure pregnenolone formed from endogenous cholesterol in adrenal mitochondrial incubations. The results from a quiescent sacrifice indicated greater SCC activity in the ARH group (0.75 nmoles prognenolone⁄minute⁄mg protein) than in controls (0.45 nmoles pregnenolone⁄minute⁄mg protein). This was related to the significantly greater (p < 0.001) amount of SCC cytochrome P-450 in the high spin state observed in adrenal mitochondria from the ARHgroup (determined by the pregnenolone-induced modified Type II spectral, change). After ether stress, both control and ARH groups had comparableamounts of high-spin SCC c...

Lung function and structure were studied in anaesthetized rabbits subjected to endotracheal instillation of Hartmann's solution (Group I) or 0.1 N HCl (pH 1.0) (Group II) in order to differentiate mechanical effects from those caused by the chemical burn. In both groups a marked and similar decrease in static lung compliance and Pao2 was observed 10 minutes after the instillation. During the subsequent hour the measurements changed towards recovery in Group I, while in Group II they fell to approximately 50% of baseline, and profound metabolic acidosis developed. The lungs showed histological changes similar to those of the clinical acid aspiration syndrome with the possible presence of a localized consumption coagulopathy. The data suggest a biphasic response to acid aspiration. The early disturbance, independent of the pH of the aspirate, is attributed to airway closure and alveolar collapse following contact between the fluid and airway receptors, and to alveolar instability resulting from an alteration in alveolar surface forces. Subsequent deterioration resulted from the acid burn.

The effect of five different anaesthetic agents (urethane, chloralose, pentobarbital, fentanyl-fluanisone and ether) on the formation and stability of haemostatic plugs in transected microvessels of the rabbit mesentery was studied. Ether significantly decreased the frequency of rebleeding through previously stable haemostatic plugs. There were no significant differences between the other four agents although there was a tendency to decreased plug stability during pentobarbital anaesthesia. It is concluded that, despite some theoretical disadvantages, urethane offers the most convenient and satisfactory form of anaesthesia for studies on haemostatic plug formation using the rabbit mesenteric preparation.

To investigate ribosome topography and possible function, 70S ribosomes of Escherichia coli were reacted with the dicarbonyl compound kethoxal. Ribosomal protein was extracted after reaction, and through two dimensional gel electrophoresis, the reactive proteins of the two subunits were identified. From the 30S subunit, the most reacted proteins were S2, S3, S4, S5 and S7 and from the 50S subunit, L1, L5, L16, L17, L18 and L27. The results with kethoxal are compared with other modifiers of ribosomal proteins.

The influence of halothane, chloroform and propanidid on hexokinase, phosphoglucose-isomerase and phosphofructokinase was studied in vitro. None of the three anaesthetic agents significantly inhibited the activity of hexokinase or phosphoglucose-isomerase preparations. A significant inhibition of phosphofructokinase was brought about by halothane, chloroform and propanidid. The inhibitory effect proved to be dependent upon the concentration of the anaesthetic drugs. It is unlikely that the resulting weak inhibition of glycolysis is causally related to the acute cardiodepressive action of the anaesthetic agents studied. However, the inhibition of glucose oxidation by halothane and other potent anaesthetic agents might be harmful after prolonged exposure, especially since significant accumulation in cardiac and other tissues occurs.

Seven representative isolates from six outbreaks of acute haemorrhagic conjunctivitis were shown to have the characteristics of enteroviruses. Two viruses differed from the remaining five isolates in producing paralysis in suckling mice and being resistant to 2-hydroxybenzyl-benzimidazole. These two viruses were also closely related antigenically and distinct from the other five viruses which were serologically similar to each other. Neither group of viruses was inhibited by antisera to the known enteroviruses and they probably represent two new enterovirus types one related to the Coxsackie A viruses and the other to the echoviruses.

Administration of single intragastric doses of ethoxyquin (500 mg/kg) to rats dramatically increased the hexobarbitone sleeping time. Conversely, dietary administration of ethoxyquin (0.5% w/w) for 14 days led to a 50 per cent decrease in the hexobarbitone sleeping time. Single doses of ethoxyquin had little effect on hepatic mixed function oxidase activity. Ethoxyquin was shown to be a potent competitive inhibitor of rat hepatic microsomal biphenyl 4-hydroxylase and ethylmorphine N -demethylase in vitro ( K i = 4.3 × 10 −6 M and 6.0 × 10 −6 M respectively) and displayed a type 1 binding spectrum with cytochrome P-450 with a very high affinity ( K s = 1.06 × 10 −5 M). Ethoxyquin had no inhibitory effect on the activity of glucose-6-phosphatase in vitro .

Analysis of the lipids collected from the shin surface of the ox has shown the presence of a significant concentration of triglyceride. The fatty acid composition of the total skin surface lipid indicated the presence oj about 10% of a CI8 dienoic fatty acid which was predominantly associated with the triglyceride fraction. This acid has been confirmed to be the 9 eis, 12 eis acid, linoleic acid. The distinctive fatty acids of the triglycerides found on the skin surface of the ox has been compared with the fatty acid composition obtained for triglycerides isolated front other tissues of the body.

This study reports the effects of precociously inducedpuberty upon basal serum corticosterone levels and the response to ether stress (ES) in maturing female rats. Precocious puberty was produced by 2

Ascospores of Saccharomyces cerevisiae are considerably less sensitive to ether than vegetative yeast. Sporulated cultures grown on either liquid or solid media can be treated with ether to selectively kill vegetative organisms. This differential sensitivity of vegetative cells can be exploited to advantage in a number of genetic manipulations. These include: random spore analysis; selecting mutants affected in the developmental processes of sporulation and spore germination; detection of sporulating revertants or recombinants from non-sporulating diploids; determination of the incidence of spores present in cultures at frequencies as low as 1 per 106 viable organisms; and, complementation testing of developmental mutations.

SUMMARY The influence of several corticosteroids on stress-induced secretion of adrenocorticotrophin was studied. Two periods of inhibition were demonstrated. Fast feedback occurred within minutes with small doses of corticosterone, and was of short duration which was further curtailed as the dose of corticosterone was raised. Delayed feedback occurred after 1 h or later, required larger doses and the duration of inhibition was increased with increased dosage. Corticosterone and cortisol were agonists on both fast and delayed feedback. However, 11-deoxycorticosterone and 11-deoxycortisol were antagonists on fast feedback but agonists on delayed feedback. It is concluded that the two feedback mechanisms have different dynamics and separate receptors.

ALTHOUGH SEVERAL WELL DOCUMENTED ABTICLES 1-7 are available on the history of surgical anaesthesia in Canada, it has not been fully elucidated when information about ether anaesthesia was first brought from the United States to Canada. Furthermore, the available sources eontain conflicting reports as to who administered the first surgical anaesthetic with ether and chloroform, as well as the first obstetrical anaesthetic. Fuller 2 states that Dr. Almon was the first to use chloroform for surgical anaesthesia; yet Shields 5 attributes the first chloroform anaesthetic to Dr. A.F. Holmes. According to a recent article by Jacques, 6 Dr. Worthington was the first to administer both ether and chloroform during surgical operations. McKenzie 1 and Fuller 2 report that a chemist, Frazer, of Nova Scotia, administered chloroform to his wife during delivery and that consequently this was the first obstetrical anaesthetic. However, Heagerty 3 credits Dr. Holmes with its first use for parturition in Canada. Thus it is still unclear exactly when, where and who administered the first surgical and obstetrical anaesthetics with ether or chloroform in Canada. It seems appropriate therefore to provide a chronology of the history of early surgical anaesthesia in Canada, in the hope that this may be helpful to future historians.

The effect of proteins upon diethyl ether extraction of phospholipids from aqueous dispersions has been investigated as a model for elucidating lipid-protein interactions in the more complex membrane systems. Mixed phospholipids having a net anionic charge or purified lecithin (a zwitterion) are extracted from water dispersions into ether only after addition of salts. Basic proteins (lysozyme and cytochromec), by ionically binding phospholipids, allow extraction. Phospholipids are extracted together with the proteins in the form of neutralized lipid-protein complexes. On the other hand, lipid depleted mitochondria (a hydrophobic protein residue after acetone extraction of mitochondria), after reconstitution with phospholipids, do not allow phospholipid extraction unless salts or basic proteins also are added to the system. This observation indicates that, in reconstituted membranes, the phospholipids are largely in the bilayer form with the polar heads still charged and susceptible to ether extraction only after neutralization with salts or basic proteins.

Summary A virus (HSIS) originating from dead owls was successfully cultivated in chicken embryo fibroblasts. Its replication was inhibited by IUDR. Tissue cultured virus proved sensitive to ether, chloroform, 0.5 per cent trypsin, and to pH levels of 4.0 or lower. Infectivity was rapidly destroyed at 56° C. Negatively stained naked virions of 100 nm average diameter were seen, and enveloped virions with 160–250 nm size. The capsid was built up of hollow cyclindrical capsomeres, arranged in equilateral triangles, carrying 5 capsomeres along each edge. Cubical symmetry and icosahedron structure yielded a total number of 162 capsomeres. All these biochemical and biophysical data lead to classification of HSIS virus into the genus herpesvirus. Biological properties described in a foregoing paper sustained such grouping, and indicated that the agent was a new avian herpesvirus for which the nameherpesvirus strigis was proposed.

Relative permittivity and resistivity of zinc oxide-eugenol cements was measured during setting. During setting the relative permittivity goes through a very pronounced maximum; simultaneously, resistivity suddenly increases by a few orders of magnitude. Such behavior is explicable in the initial function of water, which subsequently becomes bound.

SUMMARY The effects of diethyl ether and halothane anaesthesia on the arterial blood glucose, redox potential and plasma immunoreactive insulin were investigated in man. During ether anaesthesia the plasma insulin levels increased, while the blood redox potential decreased. During halothane anaesthesia no such changes were found.