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The Kir1.1 (ROMK) family of weak inward rectifiers controls K secretion in the renal CCT and K recycling in the renal TALH. A single point mutant of the inward rectifier, F127V-Kir1.1b was used to investigate the K transition between the selectivity filter and the outer mouth of the channel. We hypothesize that normally an aromatic Phe at the external entryway of Kir1.1b facilitates outward K secretion. We tested this by replacing F127-Kir1.1b with a small aliphatic Val . Results indicate that removal of the Phe at 127 suppresses outward currents that normally contribute to K secretion. Results with the F127V mutant could be explained by increased polyamine block and/or a decrease in the avidity of Kir1.1 for K ions near the outer mouth of the channel. The latter is supported by F127V-Kir1.1b having a lower affinity (K m  = 33 mM) for K than wild-type Kir1.1b (K m  = 7 mM) during external K elevation. Conversely, chelation of K with 18-Crown-6 ether reduced K conductance faster in F127V (half-time = 6s) than in wt-Kir1.1b (half-time = 120s), implying that F127V is less hospitable to external K. In other experiments, positive membrane potentials gated the F127V mutant channel closed at physiological levels of external Ca, possibly by electrostatically depleting K adjacent to the membrane, suggesting that the Phe residue is critical for outward K secretion at physiological Ca. We speculate that the avidity of wt-Kir1.1b for external K could result from a cation-Pi interaction between K and the aromatic F127.

On December 19, 1846, at the London home of Francis Boott, dentist James Robinson administered the vapor of diethyl ether to a young female patient named Miss Lonsdale. This was the earliest known attempt in England to provide painless operating conditions for a dental extraction, and it was successful. Many authors have since written much about Boott and Robinson, but scarcely anything is known about Miss Lonsdale. In contemporaneous accounts of the event, Robinson referred to his patient as a "young person" and a "young lady"; Boott, however, named her, suggesting that she was publicly recognizable. Our initial attempt to identify Miss Lonsdale was based on genealogical, United Kingdom Census, and other public records, using selection criteria based on age, name recognition, familial relationships, and London addresses. This produced 7 possible candidates from publicly recognizable families, though none was notable in her own right. Our second attempt was based primarily on contemporaneous newspaper records, among which were published 2 private letters in which Boott referred to Robinson's patient as a "girl." We found that "Miss Lonsdale" was the publicly recognizable name of 2 young stage-performing sisters, Adeline Lonsdale, a danseuse, and Annie Lonsdale, an actor-comedienne. Both subsequently emigrated to the United States where they were well-known stage performers. Accordingly, we suggest that both are highly probable candidates for that etherized patient, with the younger sister Adeline then more publicly recognizable. However, no records were found that directly associated any of the Miss Lonsdale candidates with that first dental anesthetic in England., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2023 International Anesthesia Research Society.)

Understanding anaerobic biodegradation of ether oxygenates beyond MTBE in groundwater is important, given that it is replaced by ETBE as a gasoline additive in several regions. The lack of studies demonstrating anaerobic biodegradation of ETBE, and its product TBA, reflects the relative resistance of ethers and alcohols with a tertiary carbon atom to enzymatic attack under anoxic conditions. Anaerobic ETBE- or TBA-degrading microorganisms have not been characterized. Only one field study suggested anaerobic ETBE biodegradation. Anaerobic (co)metabolism of ETBE or TBA was reported in anoxic microcosms, indicating their biodegradation potential in anoxic groundwater systems. Non-isotopic methods, such as the detection of contaminant loss, metabolites, or ETBE- and TBA-degrading bacteria are not sufficiently sensitive to track anaerobic biodegradation in situ. Compound- and position-specific stable isotope analysis provides a means to study MTBE biodegradation, but isotopic fractionation of ETBE has only been studied with a few aerobic bacteria (εC -0.7 to -1.7‰, εH -11 to -73‰) and at one anoxic field site (δ 2 H-ETBE +14‰). Similarly, stable carbon isotope enrichment (δ 13 C-TBA +6.5‰) indicated TBA biodegradation at an anoxic field site. CSIA and PSIA are promising methods to detect anaerobic ETBE and TBA biodegradation but need to be investigated further to assess their full potential at field scale., (© 2024. The Author(s).)

Nucleophilic deprotection of p-methoxybenzyl (PMB) [p-methoxyphenylmethyl (MPM)] ethers was developed using a heterogeneous oxovanadium catalyst V-MPS4 and a thiol nucleophile. The deprotection method had a wide reaction scope, including PMB ethers of primary, secondary, and tertiary alcohols bearing various functional groups. In addition, the PMB ether of an oxidation-labile natural product was successfully removed by V-MPS4 catalysis, while a common oxidative method of PMB deprotection afforded a complex mixture. The V-MPS4 catalyst was reusable up to six times without a significant loss in the product yield. The advantages of using the heterogeneous catalyst were further demonstrated by conducting the deprotection reaction in a continuous flow process, which resulted in a 2.7-fold higher catalyst turnover number and 60-fold higher turnover frequency compared to those of the corresponding batch reaction.

In order to reduce the impact of greenhouse gases on the environment, the development of various new CO 2 capture materials has become a hot spot. In this work, a novel composite amine solid adsorbent was prepared by simultaneously using tetraethylenepentamine (TEPA) and 2-[2-(dimethylamino) ethoxy] ethanol (DMAEE) for amine functionalization on the polyester microsphere carrier. The introduction of methyl methacrylate (MMA) with high glass transition temperature into the polyester carrier makes the carrier microspheres have high hardness. At the same time, the carrier also contains active epoxy groups and hydrophobic glycidyl methacrylate (GMA, which can undergo ring-opening reaction with composite amines to achieve high-load and low-energy chemical grafting of amines on the carrier. The composite aminated polyester microspheres were used as an efficient adsorbent for CO 2 in simulated flue gas. The results show that the synergistic effect of TEPA-DMAEE composite amine system in the adsorbent is beneficial to the improvement of CO 2 capture capacity. When the total amine content in the impregnating solution is 45 wt% and the composite amine ratio is TEPA: DMAEE = 6: 4, the CO 2 adsorption capacity can reach the optimal value of 2.45 mmol/ g at 70 °C. In addition, the composite amine microsphere adsorbent has cyclic regeneration performance. Importantly, through kinetic fitting, the Avrami kinetic model fits the CO 2 adsorption better than the quasi-first-order and quasi-second-order kinetic models, which proves that physical adsorption and chemical adsorption coexist in the adsorption process. This simple, long-term stable and excellent selective separation performance makes amine-functionalized adsorbents have potential application prospects in CO 2 capture., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In order to realise high ionic conductivity and improved chemical stability, a series of anion exchange membranes (AEMs) with semi-interpenetrating polymer network (sIPN) has been prepared via the incorporation of crosslinked poly(biphenyl N-methylpiperidine) (PBP) and spirobisindane-based intrinsically microporous poly(ether ketone) (PEK-SBI). The formation of phase separated structures as a result of the incompatibility between the hydrophilic PBP network and the hydrophobic PEK-SBI segment, has successfully promoted the hydroxide ion conductivity of AEMs. A swelling ratio (SR) as low as 12.2 % at 80 °C was recorded for the sIPN containing hydrophobic PEK-SBI as the linear polymer and crosslinked structure with a mass ratio of PBP to PEK-SBI of 90/10 (sIPN-90/10 (PEK-SBI) ). The sIPN-90/10 (PEK-SBI) AEM achieved the highest hydroxide ion conductivity of 122.4 mS cm -1 at 80 °C and a recorded ion exchange capacity (IEC) of 2.26 meq g -1 . Atomic force microscopy (AFM) and transmission electron microscopy (TEM) clearly revealed the improved phase separation structure of sIPN-90/10 (PEK-SBI) . N 2 adsorption isotherm indicated that the Brunauer-Emmett-Teller (BET) surface area of the AEMs increased with the increase of microporous PEK-SBI content. Interestingly, the sIPN-90/10 (PEK-SBI) AEM showed good alkaline stability for being able to maintain a conductivity of 94.7 % despite being soaked in a 1 M sodium hydroxide solution at 80 °C for 30 days. Meanwhile, a peak power density of 481 mW cm -2 can be achieved by the hydrogen/oxygen single cell using sIPN-90/10 (PEK-SBI) as the AEM., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Morpholine, a heterocycle composed of an ether and amine, is commonly used as a precursor in many organic synthesis processes because of the nucleophilicity induced by the lone-pair electrons of the nitrogen atom within its ring. Herein, we investigated the conformer-specific photoionization dynamics of morpholine under molecular-beam conditions using high-resolution vacuum ultraviolet mass-analyzed threshold ionization (VUV-MATI) mass spectroscopy. Two-dimensional potential energy surfaces (2D PESs) associated with the conformational changes in the neutral (S 0 ) and cationic (D 0 ) ground states were constructed to identify the conformer(s) corresponding to the obtained VUV-MATI spectrum. The 2D PESs indicated that the chair and twisted boat forms with equatorial and axial NH conformations (four conformers with the following relative energies: Chair-Eq < Chair-Ax ≪ Twisted boat-Ax < Twisted boat-Eq) of morpholine lie on the global minimum of the S 0 state. However, only the axial-like NH conformation in each form (stable Chair-Ax-like + ˙ and Twisted boat-Ax-like + ˙ conformers) exists in the D 0 state. Accordingly, vibration assignment was performed based on Franck-Condon (FC) analyses of the adiabatic ionic transitions from each Chair-Eq and Chair-Ax conformer to the Chair-Ax-like + ˙ conformer. The FC analyses revealed that only the Chair-Ax conformer contributes to the ionic transitions to the Chair-Ax-like + ˙ conformer owing to the large FC factors, whose adiabatic ionization energy was determined to be 8.1003 ± 0.0005 eV. Consequently, adiabatic ionization arises because of electron removal from the highest occupied molecular orbital consisting of the nonbonding orbital of the N atom in the Chair-Ax conformer.

Although physiologically based kinetic (PBK) modeling is informative for the risk assessment of industrial chemicals, chemical-specific input values for partition coefficients and metabolic parameters, including V max and K m are mostly unavailable; however, in silico methods, such as quantitative structure-property relationship (QSPR) could fill the absence. To assess the PBK model validity using necessary toxicokinetic (TK) parameters predicted by QSPR, the PBK model of ethyl tert-butyl ether (ETBE) as a model substance was constructed, in which the values of the partition coefficients, V max , and K m of ETBE were predicted using those of the related chemicals previously reported in the literature, and toxicokinetics of inhaled ETBE were stochastically estimated using the Monte Carlo simulation. The calculated ETBE concentrations in venous blood were comparable to the measured values in humans, implying that the reproducibility of ETBE toxicokinetics in humans was established in this PBK model. The Monte Carlo simulation was used to conduct uncertainty and sensitivity analyses of the dose metrics in terms of maximum blood concentration (C max ) and area under the blood concentration-time curve (AUC) and the estimated C max and AUC were highly and moderately reliable, respectively. Conclusively, the PBK model validity combined with in silico methods of QSPR was demonstrated in an ETBE model substance. QSPR-PBK modeling coupled with the Monte Carlo simulation is effective for estimating chemical toxicokinetics for which input values are unavailable and for evaluating the estimation validity.

The diffusion behavior of Mg 2+ in electrolytes is not as readily accessible as that from Li + or Na + utilizing PFG NMR, due to the low sensitivity, poor resolution, and rapid relaxation encountered when attempting 25 Mg NMR. In MgTFSI 2 /DME solutions, "bound" DME (coordinating to Mg 2+ ) and "free" DME (bulk) are distinguishable from 1 H NMR. With the exchange rates between them obtained from 2D 1 H EXSY NMR, we can extract the self-diffusivities of free DME and bound DME (which are equal to that of Mg 2+ ) before the exchange occurs using PFG diffusion NMR measurements coupled with analytical formulas describing diffusion under two-site exchange. The high activation enthalpy for exhange (65-70 kJ/mol) can be explained by the structural change of bound DME as evidenced by its reduced C-H bond length. Comparison of the diffusion behaviors of Mg 2+ , TFSI - , DME, and Li + reveals a relative restriction to Mg 2+ diffusion that is caused by the long-range interaction between Mg 2+ and solvent molecules, especially those with suppressed motions at high concentrations and low temperatures.

The aim of this article is to make a case for the pertinence of a biographical approach to the history of scientific objects. I first lay out the rationale of that approach by revisiting and extending my earlier work on the topic. I consider the characteristics of scientific objects that motivate the biographical metaphor, and I indicate its virtues and limitations by bringing out the positive and negative analogies between biographies of scientific objects and ordinary biographies. I then point out various ways in which scientific objects may pass away and argue that their demise should be conceptualized as a process. Finally, I sketch the history of the concept of "ether" in nineteenth and early twentieth century physics and suggest that it lends itself particularly well to a biographical treatment. To that effect, I discuss the identity, heuristic character, and recalcitrance of the ether and examine the reasons that may have led to its passing.

Aerobic degradation of ethyl tert-butyl ether (ETBE), Methyl tert-butyl ether (MTBE) and tert-amyl methyl ether (TAME), as tertiary-substrates, was studied in a continuous upflow fixed-bed reactor (UFBR) using an external oxygenator and sintered glass rings as biomass carriers. The UFBR has been shown to be an effective system for the simultaneous and continuous long-term degradation of the three-oxygenates mixture as sole source of carbon and energy. Therefore, the oxygenates feed concentration must be related in conjunction with the hydraulic retention time "HRT" and vice versa. The permissible feed concentration of both MTBE and TAME to achieve more than 99% removal efficiency is about 80 mg L-1 at a constant HRT of 24 h. The same performance can be obtained if the HRT kept at a value equal or above to 15 h for a feed concentration of about 80 mg L-1 of both MTBE and TAME. However, the ETBE removal efficiency was always greater than 99% whatever the ETBE concentration feed (between 10 and 100 mg L-1 at a constant HRT of 24 h) and the HRT (between 24 and 13 h at a constant concentration feed of about 80 mg L-1) tested in this study. The highest ETBE, MTBE and TAME removal rates achieved throughout the UFBR runs, with efficiency better than 99%, were 140 +/- 5, 132 +/- 2 and 135 +/- 2 mg L-1 d-1, respectively. No metabolic intermediates including tert-butyl alcohol (TBA), tert-butyl formate (TBF) and tert-amyl alcohol (TAA) were detected in the effluent during all the reactor runs. Furthermore, based on the chemical oxygen demand balance, all the removed oxygenates were completely metabolized. The results of this study suggest that the higher resistance to biodegradation exhibited by the MTBE and the TAME is probably due to the steric hindrance for the attacking enzyme(s); and the major limiting step to the oxygenate degradation maybe the accessibility and the cleavage of the ether bond, but not the assimilation of their major metabolites such as TBA, TBF and TAA. These results were concomitant with the batch tests using the reactor's immobilized biomass as inoculum.

We have demonstrated the capacity of non-phospholipid liposomes composed primarily of dioxyethylene acyl ethers and cholesterol to fuse with membranes composed primarily of phospholipid. Phase-contrast microscopy, freeze-fracture electron microscopy and a macromolecular probe indicate that these non-phospholipid liposomes can fuse with the plasma membranes of erythrocytes and fibroblasts. Furthermore, fluorescence probe experiments have demonstrated fusion between phosphatidylcholine liposomes and non-phospholipid liposomes. Mixing of internal contents was shown by a terbium/dipicolinate assay. Mixing of membrane lipid components was demonstrated by measuring (i) fluorescence resonance energy transfer between N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)phosphatidylethanolamine and N-(lissamine rhodamine B sulfonyl)phosphatidylethanolamine, after phosphatidylcholine liposomes were mixed with non-phospholipid liposomes, and (ii) reduced concentration quenching of rhodaminephosphatidylethanolamine and octadecylrhodamine incorporated into phosphatidylcholine liposomes after mixing with the non-phospholipid liposomes. The degree of apparent fusion reported by the different probe techniques ranged from 25% to 64%.

Oscillatory phenomenon at an oil-water interface in the presence of hexadecyltrimethylammonium bromide (CTAB) has been studied. The oscillation was attributable to successive formation and destruction of surfactant monolayer. According to the temperature elevation, the frequency of the electrical oscillation increased whereas the amplitude decreased. Addition of diethylether increased the frequency and decreased the amplitude. These effects of temperature and anesthetic were analyzed by the theory of the "N"-shaped relationship between surface-pressure and surface-concentration of the surfactant.

True reference values (TRV) should ultimately be determined in blood from inactive, unstimulated rats but in practice, acceptable reference values (ARV) may be established using blood from decapitated or anesthetized animals if one is cognizant of variations associated with blood sampling procedures. Data reported here illustrate some variations in serum biochemical values following decapitation or anesthesia. Decapitation does not provide serum in which ARV for sodium, potassium or lactate dehydrogenase can be found but ARV can be determined for glucose, insulin and several other parameters. It is suggested that both TRV and ARV for serum electrolytes be determined using serum from cannulated rats. All three anesthetics raised glucose levels and ether and halothane increased alkaline phosphatase activity. Both halothane and Innovar-VetR decreased insulin:glucose ratios suggesting inhibition of insulin release from the pancreas. Innovar-VetR also produced hypoxia due to severe respiratory depression and bradycardia as well as hyperuricemia, hyperglycemia and hyperphosphatemia. Techniques most likely to provide ARV should be of the shortest possible duration, afford least respiratory and cardiovascular suppression and minimize stimulation of the sympathetic nervous system.

In a prospective comparative study of 20 patients we found that, in lymphangiography, thinning Ethiodol with ether shortens the duration of the injection significantly. No complications were seen and the quality of the images remained the same.

The halothane-diethyl ether azeotrope was evaluated in dogs as the anesthetic agent for deep surface hypothermia with total circulatory arrest for open-heart operation. All 10 animals given azeotrope in 100% oxygen (O2) experienced atrial arrhythmias during cooling, and 1 had ventricular fibrillation prior to the completion of cooling at 18 degrees to 20 degrees C. After only 30 minutes' arrest, 8 of the 10 dogs had postoperative motor disturbances. Administering the azeotrope in 95% O2 and 5% carbon dioxide (CO2) yielded markedly improved results characterized by a rapid, smooth cooling course, easy resuscitation following circulatory arrest, and rapid rewarming, and 3 out of 10 dogs experienced mild motor disturbance after 60 minutes of circulatory arrest. This method, when compared with our standard method of ether in 100% O2, resulted in reduced blood lactates and a striking improvement in clinical status on the first postoperative morning. In limited clinical trials, infants undergoing repair of congenital cardiac defects have done well and responded as expected based on the laboratory experience. Since the results with the azeotrope in 95% O2 and 5% CO2 were at least as good as, and in several instances better than, those with the standard method employing either, the nonexplosive characteristic of the azeotrope warrants continued evaluation of this agent.

The performances of an Oxford miniature vaporizer (OMV) and a Fluotec Mark III vaporizer filled with an azeotropic mixture of halothane and diethyl ether were studied. Gas concentrations were estimated using an EMMA gas analyser and a MIRAN spectrophotometer. Calibration tables for both vaporizers were derived. In a small clinical series with air as the carrier gas, to which a small amount of oxygen was added, the azeotrope was found to be a satisfactory anaesthetic agent, giving a short awakening time and an almost pain-free postoperative course.

Ethyl acetate and diethyl ether were compared for their ability to recover Ascaris spp. and Trichuris spp. eggs from seeded milorganite, liquid sludge, and cabbage. Concentrations of 10, 100, and 1000 eggs/10 g test sample were prepared for 20 replicates of each product. The use of diethyl ether yielded fewer eggs/10 g than did ethyl acetate in 5 of 6 sets of data. For Ascaris spp., recovery from cabbage was 10 times higher with ethyl acetate at the higher concentration than with diethyl ether. For Trichuris spp., recovery from liquid sludge was slightly higher with diethyl ether for all egg concentrations. The other results ranged from 0 to 23% difference in recovery for the 2 agents. Depending on the parasites in question and the products to be screened, the substitution of ethyl acetate for diethyl ether may be significant.

Two functional performance parameters (heart rate and coronary flow rate) of three groups of six isolated beating hearts obtained from rats anesthetized by inhalation of diethyl ether in air, injection intraperitoneally of sodium pentobarbital (60mg/kg) or intravenously of alphaxalone/alphadolone (15mg/kg) were compared. Differences were small, but alphaxalone-alphadolone showed lowest stable mean coronary flow rate and diethyl ether the widest variation between animals. No significant difference in function was found between ether and pentobarbital, currently the two most widely used methods. But, pentobarbital showed higher stable functional performance and least variation between animals. We conclude that pentobarbital is the most useful of these three agents for obtaining hearts for perfusion as isolated beating organs, and that alphaxalone-alphadolone is clearly less suitable.

Thirty adult mongrel dogs were divided into 3 equal groups and studied to define the optimal PCO2 level with azeotrope (halothane-diethyl ether) anesthesia under surface hypothermia (Groups I, II and III = F1CO2 0%, 5% and 10%, respectively). All animals were cooled to 18-20 degrees C and were subjected to 30 (Group I) or 60 minutes (Groups II and III) of total circulatory arrest. Group I animals had frequent arrhythmic episodes during cooling and postoperative motor disturbances occurred in 80% despite only 30 minutes of circulatory arrest. By contrast Group II animals were less arrhythmic during cooling; were easily resuscitated following 60 minutes of arrest and only 30% developed moderate reversible motor disturbances postoperatively. Hemodynamics were similar between Groups II and III during cooling but resuscitation using an F1CO2 of 10% (Group III) was extremely difficult and required massive cardiotonic support throughout rewarming. Furthermore, two dogs in Group III died within the first two postoperative days. However, none of the 8 survivors displayed neurological abnormalities. On balance, a ventilatory regimen utilizing 5% CO2 during surface-induced hypothermia under azeotrope anesthesia resulted in optimum intraoperative management and a satisfactory postoperative course and although some CNS disturbance (high-stepping gait) was noted, all animals recovered completely.

Anaesthesia for Caesarean sections performed during 1982-83 at the Women's Hospital in Kathmandu, Nepal is reviewed. In a twelve-month period 535 Caesarean sections were performed, representing 7.36 per cent of 7,263 deliveries. Many pregnant women in Nepal do not have antenatal care and the mean haemoglobin of these mothers was 86 g X L-1. In the absence of an on-call anaesthetist for obstetrics, more than 90 per cent of the anaesthetics were given by junior obstetric residents, using open drop diethyl ether without endotracheal intubation. Eleven patients developed postoperative chest infection; in none of these was there any suggestion of inhalation of gastric contents and all recovered uneventfully. Of the 18 maternal deaths in the 7,263 deliveries during this period, one occurred during Caesarean section. This was due to uncontrollable haemorrhage and was not attributable to the anaesthetic. For poor risk patients, and in unskilled hands, diethyl ether remains a remarkably safe anaesthetic.

A study was performed to evaluate the antiemetic effects after ether anesthesia when dehydrobenzperidol (DHB) and pentobarbital were used for premedication and to compare these effects with halthane anesthesia when pentobarbital was used as premedication. Eighty-four patients undergoing minor surgical operations were randomly divided into three groups. The patients received ether and ether DHB 0.2 mg/kg or pentobarbital 2 mg/kg for premedication, or halothane and pentobarbital 2 mg/kg for premedication. The complaints of nausea and vomiting were recorded 24 h after anesthesia. We found that DHB compared to pentobarbital had a greater antiemetic effect after ether anesthesia, but the difference was not significant (P greater than 0.05). However, if only persistent nausea and vomiting were considered, the difference was significant (P less than 0.05). The incidence of nausea/vomiting after ether anesthesia with DHB as premedication was a little higher compared to halothane anesthesia with pentobarbital as premedication, but the difference was not significant (P greater than 0.05). However, if only persistent nausea/vomiting was considered, the incidence of complaints was equal in the two groups. It is concluded that when used for premedication to ether anesthesia DHB seems to lead to less postanesthetic nausea/vomiting than pentobarbital. Further DHB seems able to reduce the incidence of nausea/vomiting after ether anesthesia roughly to the level of that seen after pentobarbital premedication for halothane anesthesia.

A model for the simultaneous study of gastric evacuation and small bowel propulsion in the rat is presented. By means of a modification, with both indwelling duodenal and gastric tubes, studies on fully conscious animals were possible. Gastric evacuation and small bowel propulsion were analysed with respect to the effects of ether anesthesia and gastric intubation. The gastric intubation in ether anaesthesia greatly retarded gastric evacuation but left small bowel propulsion unaffected one day after laparotomy. The main factor retarding gastric evacuation appeared to be the oro-gastric intubation procedure. Ether anaesthesia neither affected gastric evacuation nor small bowel propulsion after laparotomy when the test meal was deposited into the stomach and into the duodenum, respectively, via the permanent tubes.

Hypothermal mice were used under the anesthetized condition with ether to clarify the effect of diminished blood circulation on the dispositions of creatinine and urea which are considered to pass through the water-filled pores of biological membranes easily. The total body clearance of each chemical was considerably decreased in hypothermal mice compared with normal mice. This was considered to be caused by the decrease of glomerular filtration rate. The whole-body autoradiograms obtained following intravenous administration of 14C-urea and the rate of muscular blood flow showed that the transfer of urea from blood to muscle was apparently delayed by the decrease of muscular blood flow rate. However, the transfer of creatinine to muscle was not influenced by the change of muscular blood flow rate. This difference between creatinine and urea might be related to the higher permeability of muscular cell membrane to urea than to creatinine.

The investigations made use of ten clinically normal dogs which were subjected to an overall ether intubation anaesthesia with no surgical intervention, with the preliminary medication of a mixture of morphine and atropine applied subcutaneously. In the surgical phase (III)3 after Guedel there was full relaxation of muscles; full absence of the eye and the unconditional reflexes; downward rotation of the eye-balls; covering of the cornea up to one/third by the nictitating membrane; decrease in the lacrimal secretion and drying up of the cornea; lack of response at surgical intervention or at pricking with a needle in the interdigital space. The postnarcotic sleep continued 3-4 hours. The dogs came back to normal on the 3rd, 4th, and 5th day after anaesthesia.

Variations in tyrosine hydroxylase (TH) activity and serotonin (5-HT) content in the rat locus coeruleus were measured four days after lesion of the nucleus raphe centralis superior. Lesions were made under either ether or pentobarbital anaesthesia and, in addition, (under ether) in rats pretreated with atropine or with lesions of the medial septum. Results showed a dissociation between 5-HT reduction and TH induction, differences due to the anaesthetic used, and a possible influence from limbic centres on 5-HT in the LC. These findings are discussed in terms of the apparent complexity of raphe-coerulean interactions.

A method of inhalation anaesthesia using diethyl ether, following induction with thiopentone, is described in ponies. The high concentrations of ether needed to maintain anaesthesia were obtained by using a Marrett head in circle vaporizer. This methods would only be used in ponies, since the diameter of the tubing is too small for use on larger horses.

Arterial blood lactate, pyruvate, and excess lactate (XL) were measured and calculated in 33 patients aged 7 months to 6 years over a period of 2 hours during repair of harelip or cleft palate. When the anesthetic was diethyl ether, lactate and pyruvate levels rose significantly 60 minutes after induction of anesthesia but did not rise thereafter. Excess lactate appeared 60 minutes after induction of ether anesthesia, but it, too, showed no further increase. When the anesthetic was halothane there was no significant change in lactate, pyruvate, or XL. Changes with ether were not age-related, nor could they be correlated with changes in rectal or skin temperature. The responses of lactate, pyruvate and XL to ether anesthesia in the present study were not significantly different from those found by others in adults.

Six heavily fluorinated aliphatic compounds and four heavily fluorinated derivatives of diethyl ether have been examined as anaesthetics, using mice. Two compounds are felt to be worth further examination. These are 1,1,1,-trifluoro-2,2-dichloroethane (halothane with the bromine atom replaced by a second chlorine) and 1,1,2,2,4,5,5-heptafluoro-3-oxapentane (ordinary diethyl ether with seven hydrogen atoms replaced by fluorine).