Safety and potency of ANQ 9040 in male volunteers

BACKGROUND

ANQ 9040 is an experimental nondepolarizing neuromuscular relaxant. Initial investigations in animals had indicated a rapid onset of action comparable to that of succinylcholine. The purpose of this study was to assess the safety and potency of ANQ 9040 in humans.

METHODS

ANQ 9040 was assessed in 41 male volunteers. Anesthesia was induced with propofol and maintained with a propofol infusion and 60% N2O/40% O2. Neuromuscular function was measured by mechanomyography using train-of-four stimulation of the ulnar nerve every 12 s. After an initial pilot study, 23 volunteers received a single dose of ANQ 9040 of between 0.5 and 1.1 mg/kg to determine the dose-response relationship. The final 10 volunteers were given twice the estimated ED95 of ANQ 9040 as a single bolus dose.

RESULTS

The estimated ED50 and ED95 of ANQ 9040 were 0.6 and 1.3 mg/kg, respectively. Apart from an increase in heart rate, no important adverse effects were noted after ANQ 9040 administration in the dose range 0.5-1.1 mg/kg. In the volunteers who received 2.6 mg/kg ANQ 9040, a substantial increase in plasma histamine was observed. This was associated with a 12% decrease in mean arterial pressure and a 49% increase in heart rate. In this group, the mean onset time to neuromuscular block was 51.3 s.

CONCLUSIONS

ANQ 9040 is a rapid-onset neuromuscular blocking agent. However, twice the ED95 dose is associated with significant histamine release and tachycardia. This finding suggests that this drug will not be useful in clinical practice.

The morbidity of surgical access: a study of open versus laparoscopic cholecystectomy

A prospective non-randomized study of 37 adult patients undergoing open cholecystectomy and 40 patients undergoing laparoscopic cholecystectomy was undertaken to test the hypothesis that surgical access alone has a significant impact on postoperative morbidity. Specifically the study examined the deterioration of pulmonary function, development of pulmonary complications, postoperative narcotic requirement and total bed stay as markers of postoperative morbidity. The results showed that significantly less deterioration of pulmonary function occurred in patients treated using the laparoscopic approach. In this group there was also significantly less requirement for postoperative narcotics, less consequent development of pulmonary complications and a shorter bed stay in hospital. The study documents the substantial impact of surgical access on postoperative morbidity and highlights the benefits of the laparoscopic 'minimal access' approach.

High-dose oral acyclovir reduces the incidence of cytomegalovirus infection in liver transplant recipients

To determine the impact of high-dose oral acyclovir on cytomegalovirus (CMV) infection or disease after liver transplantation, CMV cultures were prospectively collected for 6 months after transplantation. The incidence and timing of infection and disease in patients receiving high-dose oral acyclovir (3200 mg/day) from day 7 until 3 months after transplantation were compared with an historical control group who received no acyclovir. All patients who did not receive acyclovir (group 1, n = 12) but only 57% of those who did (group 2, n = 22) had CMV infection (P = .008). Nine (75%) group 1 but only 3 (14%) group 2 patients had positive leucocyte cultures (P = .0007). Three group 1 patients developed CMV disease; 1 group 2 patient developed CMV hepatitis. Each of these 4 patients had CMV viremia (P = .01). The frequency of CMV infection after liver transplantation appears to be reduced by high-dose oral acyclovir.

The effectiveness of pre-operative advice to stop smoking: a prospective controlled trial

Patients who smoke cigarettes suffer increased postoperative morbidity. A prospective, controlled trial was designed to evaluate the effectiveness of written pre-operative advice to stop smoking before admission for elective surgery and to record the duration of abstinence immediately before the operation. Although the advice was ineffective in persuading patients to stop smoking, it was associated with a reduction in the amount of tobacco consumed. Nicotine and carbon monoxide have important short-term adverse effects but 15% of all patients continued to smoke within an hour of surgery. If patients are unable to give up cigarette smoking completely, it is still worthwhile stopping on admission to hospital.

Purification and properties of the uroporphyrinogen decarboxylase from Rhodobacter sphaeroides

Uroporphyrinogen decarboxylase (EC 4.1.1.37) was purified 600-fold from Rhodobacter sphaeroides grown anaerobically in the light. The enzyme, under both denaturing and non-denaturing conditions, is a monomer of M(r) 41,000. The Km values are 1.8 microM and 6.0 microM for the conversion of uroporphyrinogen I and III to coproporphyrinogen I and III respectively. The enzyme is susceptible to inhibition by both uroporphyrinogen and uroporphyrin. The pH optimum is 6.8 and the isoelectric point is 4.4. The importance of cysteine and arginine residues is implicated from studies with inhibitors. The sequence of the first 29 amino acids of the N-terminus shows a high degree of similarity to the primary structures of other uroporphyrinogen decarboxylases. Studies on the order of decarboxylation of the four acetic acid side chains of uroporphyrinogen III suggest that at high substrate levels a random route is preferred.

Anti-tumor activity of a blocked ricin immunotoxin with specificity against the cluster-5A antigen associated with human small-cell lung cancer

The monoclonal antibody (MAb SEN31, a mouse IgG1 which recognizes the cluster-5a antigen on small-cell lung cancer (SCLC) cells, was used to prepare a selective and potent blocked ricin immunotoxin. In a series of experiments in vitro and in a SCLC xenograft model in nude mice, the tumor localization potential of the radiolabeled antibody SEN31 and the anti-tumor activity of the immunotoxin SEN31-bR, the non-specific binding activity of which had been greatly reduced by blocking of the galactose binding domains of the B-chain, was determined. Radiolabeling of SEN31 was performed by linking a 67Ga-labeled desferrioxamine moiety to the oligosaccharide side chains of the antibody in order to preserve the specific cell-binding activity. 67Ga-SEN31 bound to the antigenic sites on cells of the SW2 SCLC cell line, with a dissociation constant of 3.5 nM and, when injected i.v., selectively localized at the site of s.c.-growing SW2 tumor xenografts in nude mice, with a tumor-to-blood ratio of 3.5. The immunotoxin SEN31-bR was potently and selectively active against SCLC cell lines both of classic and of variant morphologies. At a concentration of 300 pM the immunotoxin selectively eliminated 4.5 logs of clonogenic tumor cells. In nude mice, SEN31-bR was cleared from the blood with biphasic kinetics following i.v. injection and maintained a stable serum level during continuous i.p. infusion. The growth of s.c. SW2 solid-tumor xenografts was delayed following a single i.v. injection or a continuous i.p. infusion, each at a non-toxic dose.

Attitudes towards liver transplantation in Victoria, Australia

Liver transplantation commenced on a regular basis in Australia in 1985. This followed the first successful orthotopic transplant in Brisbane in 1985 and the setting up of a National Centre for Liver Transplantation in Sydney in 1985 with clinical transplantation beginning there in 1986. A centre was subsequently developed in Melbourne in 1988. As this procedure was perceived to be expensive, and because of discussion on rationing of medical services, the authors were prompted to test the Victorian community awareness and attitude to government funding of transplantation. One year after the establishment of the Victorian Liver Transplantation Programme, a random survey of the Victorian population and of general practitioners in Melbourne was conducted with the assistance of a professional polling company. Sixty-five per cent of the Victorian population knew liver transplantation was available in Victoria, 12% said it was not available and 23% did not know. Among general practitioners, 79% knew liver transplantation was available 14% said it was not available and 7% did not know. Eighty-eight per cent of Victorians and a similar proportion of general practitioners said the State Government should provide funding. Forty-seven per cent of the Victorian population said government should provide total funding and a further 39% funding of more than 50%. Among general practitioners, 33% said total funding should be provided and a further 46% thought that more than 50% of funding should be provided. This survey has revealed convincingly that Victorians have decided that their health care should include the expense of liver transplantation paid for by government. Awareness of the availability of the operation of liver transplantation is developing rapidly.

Activity of doramectin against nematode endoparasites of cattle

A series of 28 controlled anthelmintic studies, involving 634 cattle, was conducted throughout North America and Europe to evaluate the efficacy of doramectin against a broad range of gastrointestinal parasitic nematode species and lungworms in naturally and experimentally infected animals. Within each study, one or two groups were treated with doramectin at 200 micrograms kg-1 and another group received no drug treatment. Worm burdens were estimated by standardised techniques, and efficacy assessed on reduction of worm burdens in doramectin-treated animals. Doramectin was at least 99.6% effective (P < 0.0002) in eliminating the immature and adult stages of the following 14 species of nematodes: Ostertagia ostertagi (including inhibited), Ostertagia lyrata, Haemonchus placei, Trichostrongylus axei, Trichostrongylus colubriformis, Cooperia oncophora (including inhibited), Cooperia pectinata, Cooperia punctata, Cooperia spatulata, Cooperia surnabada, Bunostomum phlebotomum, Strongyloides papillosus, Oesophagostomum radiatum and Dictyocaulus viviparus. Efficacy against adult Trichostrongylus longispicularis, Nematodirus spathiger and Trichuris spp. was 93.1%, 96.5% and 94.6%, respectively. Efficacies against adult and fourth-stage larvae of Nematodirus helvetianus, the dose-limiting species, were 73.3% and 75.5%, respectively.

The effect of finish line form and luting agent on the breaking strength of Dicor crowns

Molar teeth were prepared to a standardized cylindric form using a lathe. Dicor crowns were luted on these preparations using zinc phosphate, glass-ionomer, and resin cements. The crowns were thermocycled and subjected to fracture loading to compare the effect of the different luting agents on fracture strength. Five finishing lines were used to determine if resin cement and associated bonding procedures could counteract the negative effect certain finish lines produce on all-ceramic crowns. When resin cement was used in conjunction with restoration and tooth precementation bonding treatments, the crowns were significantly stronger than when glass-ionomer or zinc phosphate cements were used. No difference in strength was found between the five finish lines when the crowns were cemented with resin and associated bonding procedures.

Early detection and measurement of experimental myocardial infarcts with horseradish peroxidase

Current methods of experimental infarct size measurement require tissue analysis several hours after the ischemic event. Electron microscopy identifies irreversibly injured myocytes early after ischemia, but cannot be used to measure myocardial infarct size. Horseradish peroxidase (HRP), a tracer protein that permeates the disrupted sarcolemma of injured myocytes, was used to determine infarct size. New Zealand White rabbits (n = 15) were subjected to 30 min coronary artery occlusion and 24 h reperfusion. Prior to euthanasia, HRP was administered intravenously. The hearts were excised, perfused with triphenyl tetrazolium chloride (TTC), and perfusion fixed. A frozen section was cut from left ventricular slices, and the brown HRP reaction product was developed with 3,3'-diaminobenzidine tetrahydrochloride and H2O2. The areas delineated by intramyocyte HRP (as a percent of the left ventricle) closely correlated with infarct size determined by conventional hematoxylin-eosin (H&E) stain and TTC (means +/- S.E.M.): 29.5 +/- 3.0% vs 27.6 +/- 2.9% vs 28.6 +/- 2.6%, respectively. The coefficient of correlation between HRP and H&E was 0.94. This method was tested for early infarct detection in rabbits subjected to 30 min coronary occlusion followed by intravenous injection of HRP and sacrifice. HRP-delineated infarcts measured 21.4 +/- 3.7% of the left ventricle, and electron microscopic examination from ischemic and non-ischemic areas was used to confirm that cells containing HRP were irreversibly injured. Thus, HRP can be used to accurately measure myocardial infarct size in experimental coronary artery occlusion and reperfusion in infarcts as early as 30 min after coronary occlusion or following 24 h of reperfusion.

Preconditioning of heart by repeated stunning: adaptive modification of myocardial lipid membrane

Recent studies indicate that preconditioning of the heart by repeated stunning protects it from subsequent ischemic injury. Such myocardial preservation is likely to be due to adaptive modification of lipid composition and dynamic structure of cellular membrane. To test this hypothesis, swine heart was subjected to four episodes of 5 min stunning by LAD occlusion, followed by 10 min of reperfusion after each stunning. The heart was then made regionally ischemic for 60 min by LAD occlusion, followed by 6 h reperfusion. A control heart was perfused for 60 min, followed by 60 min ischemia and 6 h reperfusion. Free fatty acids (FFA) accumulated in the control heart during ischemia, as expected, which was further enhanced by reperfusion. The FFA level was also enhanced during ischemia in stunned myocardium. However, this FFA level was almost restored during reperfusion. The levels of unsaturated fatty acids (UFA) such as oleate, linoleate, and arachidonate followed a similar pattern. Membrane fluidity, monitored by fluorescence polarization, was decreased during ischemia and reperfusion in the unstunned heart, with the corresponding increase in microviscosity. The increased microviscosity was significantly reduced by stunning. Since FFA are presumably generated from membrane phospholipids, these results suggest that stunning may cause the incorporation of a greater proportion of PUFA in membrane phospholipids, leading to preservation of membrane phospholipids and maintaining the membrane fluidity, which may be at least partially responsible for the attenuation of ischemic reperfusion injury.

A putative anaerobic coproporphyrinogen III oxidase in Rhodobacter sphaeroides. I. Molecular cloning, transposon mutagenesis and sequence analysis of the gene

A mutant of Rhodobacter sphaeroides, N1, has been isolated which is incapable of photosynthetic growth and, instead of synthesizing bacteriochlorophyll, N1 excretes coproporphyrin III into the growth medium. Using conjugative gene transfer, several clones were isolated from a R. sphaeroides gene library which restored normal pigment synthesis and photosynthetic growth to N1. Using transposon Tn5 mutagenesis, the gene was located to a 1.05 kb EcoRI fragment. Sequence and transcription analysis defined the position and expression of an open reading frame of approximately 920 bp, which is proposed as the anaerobic coproporphyrinogen III oxidase dedicated to bacteriochlorophyll biosynthesis.

Preconditioning of heart by repeated stunning. Adaptive modification of antioxidative defense system

Previous studies demonstrated that preconditioning of a heart by repeated stunning can reduce the cellular injury to the heart from subsequent acute ischemic insult. To examine the possible biochemical mechanism for such myocardial preservation afforded by preconditioning, swine heart was subjected to four episodes of 5 min. stunning by occluding the left anterior descending coronary artery (LAD), followed by 10 min. of reperfusion after each stunning. Heart was then made regionally ischemic for 60 min. by LAD occlusion, followed by 6 hrs. reperfusion. Control heart was perfused for 60 min., followed by 60 min. ischemia and 6 hrs. reperfusion. The results of our studies indicated the stimulation of a number of antioxidative enzymes, including Mn-superoxide dismutase (Mn-SOD), catalase, glutathione peroxidase, and glutathione reductase, after repeated stunning and reperfusion. In addition, a number of new proteins were expressed after preconditioning the heart, including some oxidative-stress related proteins and 72 kDa heat-shock protein. These results suggest that preconditioning of a heart by repeated stunning may lead to strengthening of the oxidative defense system of the heart, which is likely to play a role in myocardial preservation during subsequent ischemic and reperfusion injury.

Colon carcinoma immunoscintigraphy by monoclonal anti-CEA antibody labeled with gallium-67-aminooxyacetyldeferroxamine

Previous experimental results in nude mice showing that radiolabeling the monoclonal antibody anti-CEA 35 with 67Ga-aminooxyacetyldeferroxamine could give better tumor localization than radioiodination prompted us to initiate the present clinical study. The 67Ga-labeled antibody anti-CEA 35 (185 MBq, 0.7-1.7 mg) was injected preoperatively into 14 patients for colorectal carcinoma imaging. The same antibody labeled with 125I (3.7 MBq, 0.25 mg) was injected simultaneously to compare the 67Ga and 125I dose recoveries in surgical specimens. Twelve of 14 primary tumors gave a positive 67Ga scintigraph. The mean %ID/g recovered in all tumors 3-9 days after injection was significantly higher for 67Ga (0.019%) than for 125I (0.005%) (p < 0.001, paired t test). The tumor-to-normal tissue ratios were generally higher for 67Ga, with the exception of liver. We conclude that 67Ga-aminooxyacetyldeferroxamine improved immunoscintigraphy outside the liver, particularly in the pelvic region. We also show that deferroxamine infusion accelerates the excretion of 67Ga in eight patients and propose that this could lead to further improvement of immunoscintigraphy.

Inhaled anaesthetic agents: from halothane to the present day

Despite the enormous resources spent on research and development, only two new volatile agents have been introduced into anaesthetic practice in the UK since the introduction of halothane. This article reviews their properties and looks towards changes in volatile anaesthetic availability in the near future.

Mivacurium chloride: a study to evaluate its use during propofol-nitrous oxide anaesthesia

We assessed the neuromuscular and cardiovascular effects of mivacurium chloride, a neuromuscular blocking agent, in 33 patients during propofol-nitrous oxide anaesthesia. Neuromuscular function was assessed with supramaximal stimuli of the ulnar nerve, using surface electrodes at the wrist, with repeat trains of four. Mivacurium given as a bolus of 0.15 mg.kg-1 (ED95 x 2) was found to be haemodynamically stable. Intubating conditions assessed at 2 and 2.5 min were either good or excellent. All patients developed a block of 100% in a mean (SD) time of 105 (34) s. There were mean (SD) intervals of 12 (2.4) min before the reappearance of the first twitch of the train of four (T1) following the bolus dose, and 15.8 (3.1) min for the T1 to reach 25% of its control value (TC). Seventeen patients received an infusion of mivacurium to maintain neuromuscular blockade (T1:TC 10-20%) with a mean (SD) infusion rate of 6.9 (2.2) micrograms.kg-1.min-1. Recovery from neuromuscular blockade was assessed with spontaneous offset or augmented with edrophonium following either the initial bolus or an infusion. Following a bolus it took a mean (SD) of 26.2 (3.7) min for the fourth twitch of the train of four (T4):T1 ratio to reach 0.7. In patients receiving an infusion with spontaneous offset it took a mean (SD) time of 12.0 (2.2) min to reach the T4:T1 ratio of 0.7 from a T1:TC value of 8.8. Edrophonium significantly decreased the recovery time in both groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Laparoscopic cholecystectomy for complicated gallstone disease

After performing selectively 25 laparoscopic cholecystectomies (LC) to determine the place of LC in the management of complicated gallstones, all patients presenting with gallstones were evaluated by the authors for LC. Eighty-six consecutive patients were evaluated and 84 were studied. Follow-up in every case exceeded 6 months. In three of 10 patients with acute cholecystitis, LC was not possible; each had a history longer than 48 h and all had gangrene of the gallbladder. In four patients with empyema, LC was successful, but operative cholangiography failed. Operative cholangiography was successful in 76 of the remaining 77. Of eight patients suspected of having stones in the CBD, cholangiography excluded stones in six and confirmed them in two. Cholangiography identified three other patients with totally unsuspected CBD stones. Of the five patients with CBD stones, four had them flushed to the duodenum at LC following transcystic balloon dilatation of the papilla and one had a post-op. ERCP. Of four patients with acute pancreatitis, three had LC in the same admission. LC was possible in all three patients with morbid obesity. We conclude that with experience, LC is possible for complicated gallstones. In acute cholecystitis, the probability of success is higher with earlier operative intervention. Operative cholangiography is essential. It not only identifies unsuspected CBD stones but also allows LC without ERCP in those with suspected CBD stones and with modification it allows treatment of those stones.

Recovery characteristics using isoflurane or propofol for maintenance of anaesthesia: a double-blind controlled trial

We studied 114 female patients (ASA 1 or 2) who were within 20% of ideal body weight and who were scheduled to undergo gynaecological laparoscopy which required supplementation with an opioid (groups IA and PA), or dental procedures which did not require opioid supplementation (groups IO and PO). A computerised package of psychomotor tests was performed before surgery. Anaesthesia was induced with propofol 2.5 mg.kg-1 and all patients received atracurium 0.3 mg.kg-1 and 67% nitrous oxide in oxygen. Patients in group IA received isoflurane 1% (inspired), and alfentanil 10 micrograms.kg-1 as a bolus and 10 micrograms.kg-1.h-1 as an infusion. Patients in group PA received propofol 9 mg.kg-1.h-1 as an infusion, decreasing to 6 mg.kg-1.h-1 after 15 min, together with alfentanil 10 micrograms.kg-1.h-1. Patients in groups IO and PO received isoflurane and propofol in the regimens described for groups IA and PA, but without alfentanil. Recovery was assessed by a blinded observer who recorded times to awakening (eye opening) and orientation (giving date of birth), and who repeated the psychomotor tests at 1, 3 and 5 h. Linear analogue scales of mood, nausea and pain were obtained and other side effects were noted in the succeeding 48 h. A matched control group of 25 females (who were not anaesthetised) underwent psychomotor testing on four occasions in order to assess the 'learning effect' of repeated recovery testing. The analysis of recovery tests did not assume a normal distribution.(ABSTRACT TRUNCATED AT 250 WORDS)

Inhaled anaesthetic agents: from ether to halothane

The introduction of general anaesthesia revolutionized surgical practice. In this workshop and the one that follows in a future issue the evolution and properties of inhalational anaesthetics are reviewed and future developments are considered. Here we look at the period between the introduction of ether and of the first modern agent, halothane.

Laparoscopic cholecystjejunostomy as palliation for obstructive jaundice in inoperable carcinoma of pancreas

Malignant obstructive jaundice can be palliated by either surgical bypass, which has the advantage of long-term patency, or by stent placement, which has the advantage of initial lower morbidity and mortality. We describe a technique, laparoscopic cholecystjejunostomy, which has the advantage of both. We predict that laparoscopic surgery, which has already had a major impact on biliary stone surgery, will also have a major impact on interventional endoscopic retrograde cholangiopancreatography.

Dentin exposure and decay incidence when removable partial denture rest seats are prepared in tooth structure

Prosthodontists surveyed preferred inverted V-shaped canine cingulum ledge rest seats located at the junction of the middle and cervical thirds of the lingual surface. Most respondents indicated that they preferred a ledge depth of at least 1.0 mm and indicated that their preparations usually did not extend into dentin. When the respondents evaluated various ledge depths, the mean depth of those judged adequate was 0.74 mm, which was less than the respondent and textbook recommendations. Premolar occlusal rest seats judged adequate generally met textbook size guidelines. The mean clinical incidence of dentin exposure with cingulum ledges and occlusal rest seats was 61%, close to the 55% exposure rate found on extracted teeth. Dentin Detector Gel effectively identified clinical dentin exposure but tooth sensitivity was not a good indicator of dentin exposure. Seventy-one of the 107 rest seats studied for incidence of caries and decalcification had exposed dentin but only two of the 71 had lesions. Ten of the 107 had small enamel fractures, primarily occurring on cingulum ledges.

Oxygen-derived free radicals and hemolysis during open heart surgery

Reperfusion injury occurs during open-heart surgery after prolonged cardioplegic arrest. Cardiopulmonary bypass also is known to cause hemolysis. Since reperfusion of ischemic myocardium is associated with the generation of oxygen free radicals, and since free radicals can attack a protein molecule, it seems reasonable to assume that hemolysis might be the consequence of free radical attack on hemoglobin protein. The results of this study demonstrated that reperfusion following ischemic arrest caused an increase in free hemoglobin and free heme concentrations, simultaneously releasing free iron and generating hydroxyl radicals. In vitro studies using pure hemoglobin indicated that superoxide anion generated by the action of xanthine oxidase on xanthine could release iron from the heme ring and cause deoxygenation of oxyhemoglobin into ferrihemoglobin. This study further demonstrated that before the release of iron from the heme nucleus, oxyhemoglobin underwent deoxygenation to ferrihemoglobin. The released iron can catalyze the Fenton reaction, leading to the formation of cytotoxic hydroxyl radical (OH.). In fact, the formation of OH. in conjunction with hemolysis occurs during cardiac surgery, and when viewed in the light of the in vitro results, it seems likely that oxygen-derived free radicals may cause hemolysis during cardiopulmonary bypass and simultaneously release iron from the heme ring, which can catalyze the formation of OH..

Perforated peptic ulcer. A further application of laparoscopic surgery

A case of perforated peptic ulcer in a patient with cervical myelopathy due to osteophyte cervical canal stenosis complicated by the sudden onset of abdominal pain is described. Diagnostic laparoscopy revealed a perforated peptic ulcer in the anterior wall of the duodenal cap. Laparoscopic treatment was suitable for this condition.

Hepatitis due to nitrofurantoin

OBJECTIVE

To report three cases of hepatitis related to the use of nitrofurantoin.

CLINICAL FEATURES

Two patients who had been taking nitrofurantoin for several years, presented with severe liver failure. In both, the drug had been continued despite evidence of liver injury. A third patient presented with acute hepatitis after six weeks of nitrofurantoin therapy.

INTERVENTION AND OUTCOME

One of the patients with liver failure died and the other underwent a successful liver transplantation. The third patient recovered after withdrawal of the drug.

CONCLUSION

These cases emphasise the potential for serious hepatic reactions with nitrofurantoin, the danger of continuing the drug once liver damage has occurred and the need for careful monitoring of liver function during long-term therapy.

Water balance and lung fluids in rats at high altitude

A disturbed water and electrolyte homeostasis is not generally held to be a primary mechanism in the pathogenesis of acute mountain sickness (AMS) and high altitude pulmonary edema (HAPE), but the association of oliguria and weight gain with AMS and HAPE has led to the hypothesis that water retention may be a facilitative mechanism, possibly caused by an effect of hypoxia to release antidiuretic hormone (ADH). To examine the problem, normal Long-Evans rats (N) and the strain with congenital diabetes insipidus (DI) were exposed to hypobaric hypoxia (0.5 atm) for 4 days, and fluid balance in the whole animals and in their lungs was studied. Both strains reduced water intake and were oliguric on acute exposure, but the N rats gained body weight and increased lung water, while the DI rats increased neither body weight nor lung water. Neither strain increased lung blood at high altitude. The oliguria in the DI rats could not have been due to a release of antidiuretic hormone, and was attributed to the diminished water intake in both strains. The protection against HAPE in the DI rats was probably due to their more severe dehydration that exists already in normoxia, and its further increase in hypoxia, compared with N rats.

Enhanced membrane protein kinase C activity in myocardial ischemia

The protein kinase activity in cytosol was similar in control, ischemic, and reperfused hearts; however, a 1.5-fold increase in membrane protein kinase activity was induced by ischemia and reperfusion. The H-7 inhibitable cytosolic protein kinase activity decreased by 40% with 30 min ischemia, while that of membrane fraction increased 1.8-fold. However, the CGS9343B inhibitable protein kinase activity in cytosolic fractions was unaffected by ischemia, while that of membrane increased by about 1.7-fold. These results suggest that myocardial ischemia is associated with enhanced protein kinase C and calmodulin-dependent kinase activities in membrane fraction. Furthermore, the results also suggest a translocation of protein kinase C activity from the cytosol to the membrane. Reperfusion of ischemic myocardium did not result in any further increase of protein kinase C and calmodulin-dependent kinase activities in the membrane. These enhanced protein kinase activities also resulted in an enhanced phosphorylation of endogenous membrane proteins. The creatine kinase released from the heart was increased by both ischemia and reperfusion. Therefore, these results suggest that biochemical cascades of reactions caused by enhanced membrane protein kinase C and calmodulin-dependent kinase activities may contribute to ischemic-reperfusion injury.

Resistance to atracurium in a patient with an increase in plasma alpha 1 globulins

We observed that a female patient with a poorly differentiated adenocarcinoma of the stomach undergoing gastrectomy was markedly resistant to the action of the neuromuscular blocking drug atracurium. There was no evidence of tumour metastasis and her liver function tests were normal. Electrophoresis of plasma proteins revealed a marked increase in alpha 1 globulin. Alpha 1 acid glycoprotein is an acute phase reactant that is increased in patients with cancer and is present in the alpha 1 globulin electrophoresis pattern. It is likely that the mechanism for the resistance to neuromuscular block in the patient was an increase in drug binding to alpha 1 acid glycoprotein.

Induction and recovery characteristics of desflurane in day case patients: a comparison with propofol

Desflurane is an ether halogenated exclusively with fluorine. It has a blood/gas partition coefficient of 0.42 (cf. isoflurane 1.40 and nitrous oxide 0.46). This characteristic suggests that it should provide both a fast induction of anaesthesia and a rapid recovery from anaesthesia. To assess this, 60 patients were entered into a study and allocated at random to one of four groups receiving either desflurane or propofol for induction and maintenance of anaesthesia. Desflurane caused loss of consciousness in approximately 2 minutes during gaseous inductions. The psychomotor scores in the patients who received propofol for induction and maintenance of anaesthesia were significantly worse compared with those who were given desflurane for either induction and maintenance or for maintenance only. There was also a tendency for other recovery parameters to be faster in the patients receiving desflurane although this did not reach statistical significance. This suggests that desflurane would be a suitable agent for day case anaesthesia providing for a rapid recovery.

A prospective study of liver function in infants and children exposed to daily isoflurane for several weeks

Eleven infants and children presenting for daily radiotherapy for a period of at least 2 weeks were anaesthetised with isoflurane in 33% oxygen and nitrous oxide. They were unpremedicated and given no other agents to supplement anaesthesia. The average number of exposures was 24 (SD 11; range 10-39) and the total anaesthetic time per exposure varied between 15 and 30 minutes. Liver function was assessed by determining serum total bilirubin, aspartate amino transferase, gamma glutamyl transferase and alkaline phosphatase before the start of treatment and at 5-daily intervals thereafter. There was no measurable change in any of these determinants of liver function. All children accepted daily induction of anaesthesia with isoflurane. Induction, maintenance and recovery from anaesthesia were uncomplicated.

The days ahead

How are government controls affecting healthcare foodservices?Are growing elderly & outpatient populations changing foodservices' missions. What are the hottest trends? As members of the American Society for Hospital Food Service Administrators prepared for their annual meeting in Orlando, FM queried 11 Southeastern directors to learn their most pressing concerns & how they are positioning their departments for the future.

Prostaglandin E1 for the treatment of primary non-function of the donor organ in liver transplantation

OBJECTIVE

To present a case in which acute failure of a liver graft was treated with an infusion of prostaglandin E1 (PGE1).

CLINICAL FEATURES

A nine-year-old girl underwent liver transplantation for Wilson's disease. Her course was complicated by primary non-function of the graft as evidenced by poor bile production, rising bilirubin and liver enzyme levels and a severe coagulopathy.

INTERVENTION AND OUTCOME

PGE1 was infused and there was recovery of graft function. The need for urgent re-transplantation was avoided.

CONCLUSIONS

PGE1 may have an important role in liver transplantation considering the logistic difficulties of obtaining donor livers for urgent transplantation in Australia.

Release of endothelin from cultured bovine endothelial cells

Recently discovered endothelin is a powerful vasoconstrictor of vascular smooth muscle in vitro, which also profoundly affects the mechanical function of the heart. An increased level of plasma endothelin in patients with acute myocardial infarction suggests the enhanced release of endothelin from vascular endothelium under pathophysiological conditions of the heart. The reperfusion of ischemic myocardium is associated with the activation of polymorphonuclear leukocytes (PMN) generating oxygen-derived free radicals (OFR), as well as, enhanced responsiveness of myocardial alpha 1-adrenergic receptor. Both OFR and catecholamines are implicated in the modulation of release of endothelium-derived peptides.