[Emergency operation and perioperative management for a patient with strangulated ileus and shock associated with Rubinstein-Taybi syndrome]

A 21-year-old white male with Rubinstein-Taybi syndrome (RTS) underwent emergency laparotomy and volvulus reduction for a strangulated ileus. Low blood pressure, rapid heart rate and dusky skin color indicated that he was in a hypovolemic and/or septic shock state. Communication with the patient was impossible because of severe mental retardation, deafness, and blindness, and he was quite combative and agitated. Because of an urgent situation and in anticipation of a great risk of regurgitation, no sedatives or anesthetics were used for induction of anesthesia. A large dose of vecuronium with a priming principle technique was the only agent used for endotracheal intubation. Vigorous fluid replacement and appropriate catecholamine therapy were required for the perioperative management and recovery from the shock state. Any cardiac episodes which have been reported in patients with RTS, such as supra-ventricular or ventricular arrhythmia, did not occur throughout the perioperative period. Lack of communication with the patient was an obstacle in the postoperative care, such as respiratory management or the estimation for the timing of extubation. In conclusion, the preparations for a possibly difficult airway and the possible occurrence of arrhythmia were thought to be prudent for the management of the patient with RTS.

Combined therapy with arbekacin and fosfomycin for methicillin-resistant Staphylococcus aureus infections

We examined the clinical efficacy of a combination of arbekacin and fosfomycin in the treatment of various methicillin-resistant Staphylococcus aureus (MRSA) infections. The combination of arbekacin plus fosfomycin displayed 65.4% (17/26) clinical efficacy and 65.4% (17/26) bacteriological efficacy. This combination thus appeared to be an effective regimen for the treatment of MRSA infections. However, its bacteriological efficacy against concomitant Pseudomonas aeruginosa strains was only 16.7% (1/6). In addition, in 4 episodes of superinfection involving P. aeruginosa strains developed during the combination therapy.

In vitro activities of arbekacin, alone and in combination, against methicillin-resistant Staphylococcus aureus

We determined the in vitro activities of arbekacin in combination with other antibiotics against 96 clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA). Efficacies were evaluated by comparing frequencies of susceptible strains at concentrations of antibiotics present in serum 3 hours after intravenous administration of recommended dosages with those obtained with addition of 1 or 2 micrograms/ml of arbekacin. The addition of arbekacin significantly increased the antibacterial activities of cefotiam, cefuzonam, flomoxef and fosfomycin, but had no effect on the activity of either imipenem or minocycline. Arbekacin in combination with fosfomycin was found to have the greatest activity against MRSA among combinations tested. In addition, arbekacin had excellent antimicrobial activity against Pseudomonas aeruginosa, compared to other anti-pseudomonal agents such as piperacillin, ceftazidime and imipenem.

Taurine amplifies renal kallikrein and prevents salt-induced hypertension in Dahl rats

OBJECTIVE

To determine whether taurine reduces blood pressure by stimulating the renal kallikrein-kinin system.

METHODS

The effects of taurine on blood pressure, urinary kallikrein activity and renal kallikrein gene expression were investigated in Dahl salt-sensitive (Dahl-S) rats. The specificity of the action of taurine was verified by comparison with the action of beta-alanine, a carboxylic analogue of taurine. The effect of co-administration of the specific bradykinin B2 receptor antagonist Hoe 140 was also examined.

RESULTS

Administration of taurine (3% in drinking water) for 4 weeks retarded the development of salt (4% sodium chloride diet)-induced hypertension. Systolic blood pressure at the end of the experiment was significantly higher in control rats than in taurine-treated rats. Urinary sodium excretion was not decreased by the reduction in blood pressure. The heart weight:body weight ratio was significantly lower, and urinary volume and kallikrein excretion were significantly higher, in taurine-treated rats. Renal kallikrein gene expression at weeks 1 and 4 was higher in taurine-treated rats. Systolic blood pressure 3 and 4 weeks after the administration of beta-alanine was slightly, but not significantly, lower than that of untreated rats on a high-salt diet, and was accompanied by a significantly lower body weight. Urinary kallikrein excretion decreased with a high-salt diet regardless of beta-alanine administration. Continuous systemic administration of Hoe 140 did not cause any significant alteration in blood pressure in Dahl-S rats that received taurine with a high-salt diet. Taurine also showed a renoprotective effect, as judged by a reduction in proteinuria.

CONCLUSION

These results suggest that taurine is an effective antihypertensive agent for salt-induced hypertension. Although taurine activated renal kallikrein, further studies are required to confirm the participation of activated kallikrein in the antihypertensive, cardioprotective and renoprotective effects of taurine.

Effect of atracurium, vecuronium, pancuronium and tubocurarine on renal sympathetic nerve activity in baroreceptor denervated dogs

The mechanism of arterial hypotension induced by non-depolarizing neuromuscular blocking agents may be multifactorial and differ between drugs. The purpose of this study was to evaluate the effect of high-dose atracurium and equivalent doses of other non-depolarizing neuromuscular blocking agents on haemodynamic state and sympathetic nervous activity. In studies on 24 mongrel dogs anaesthetized with alpha-chloralose, the left kidney was exposed retroperitoneally and renal sympathetic nerve activity was recorded continuously after bilateral sino-aortic denervation and cervical vagi section. The dogs were allocated to four groups; atracurium 1.5 mg kg-1, tubocurarine 0.3 mg kg-1, pancuronium 0.3 mg kg-1 or vecuronium 0.3 mg kg-1 was administered to six dogs in each group. Histamine 1 micrograms kg-1 was given to two dogs in each group, 1 h before administration of neuromuscular blocking agents. We observed that atracurium and tubocurarine significantly decreased arterial pressure, heart rate and renal sympathetic nerve activity (P < 0.05), but pancuronium and vecuronium did not Histamine-induced arterial hypotension but did not affect heart rate or renal sympathetic nerve activity. As both arterial and cardiopulmonary baroreflex pathways were inactivated in these animals, we conclude that atracurium decreased arterial pressure by suppressing efferent sympathetic nerve activity in a manner similar to that of tubocurarine.

Plasma HDL levels are regulated by the catabolic rate of large particles of lipoprotein containing apo-A-I

Lp-A-I was isolated by immunoaffinity chromatography and then separated into two fractions of large and small Lp-A-I particles by conventional ultracentrifugation with a cut-off density of 1.125 g/ml. The large and small particle-rich fractions were then radiolabeled with [125I]-Na and [131I]-Na, respectively. Both of the labeled lipoproteins were injected (20 microCi, i.v.) simultaneously into normolipidemic rabbits. The FCR of the large Lp-A-I particles was much less than that of the small Lp-A-I particles (0.801 +/- 0.026/day vs. 2.227 +/- 0.067/day, P < 0.0001). These data indicate that the two particles have distinctly different metabolic pathways and that the lower FCR of larger Lp-A-I particles can effectively raise plasma HDL levels.

Acute myocardial infarction due to thrombus formation in congenital coronary artery fistula

A young female patient developed acute myocardial infarction during physical exercise. Coronary arteriography in the acute phase demonstrated a coronary fistula originating from the left coronary main trunk and communicating with the right atrium. Several branches of the left coronary artery were obstructed by thrombotic material originating from the fistula, causing an acute myocardial infarction.

[Imaging and anatomical study of echinococcosis: CT and MR imaging in alveolar hydatid disease]

To elucidate the characteristics of alveolar hydatid disease on computed tomography (CT) and magnetic resonance imaging (MRI), a correlative radiologic-pathologic study was performed on fifteen rats after autopsy. The rate of lesion detection was higher for MRI (93%) than CT (77%). The preoperative CT scans of sixteen lesions in nine patients with surgically proved alveolar hydatid disease were reviewed retrospectively. Large lesions (> 5 cm in diameter) showed a soft tissue density area (50%), central necrosis with irregular thickened wall (33%), honeycomb appearance (50%) and calcification (100%). Small lesions (< 2 cm) showed only a small low density area. Confluent low density areas were pathognomonic for the early lesions. MR images were available in three patients. Enhanced MRI (SE 600/20) could show confluent low intensity areas and high intensity areas around the lesions caused by inflammation and edema, which could not be demonstrated well on CT. Metastatic lesions of lung and bone were also visualized on plain radiographs.

Coronary collateral circulation and diastolic function

Patients with coronary artery disease reportedly have an impaired left ventricular filling. To evaluate the effects of coronary collaterals on diastolic function in patients with effort-induced angina, resting radionuclide ventriculography was performed in 14 patients with severe isolated (> or = 90% diameter) stenosis of the left anterior descending coronary artery and in seven normal subjects. Contrast ventriculography showed normal wall motion in all patients. Functional indices obtained by radionuclide ventriculography were compared between those patients with collateral vessels, Rentrop classification grades 1 (n = 7) and 3 (n = 1), and those patients without (n = 6) collateral vessels. Global peak filling rate was significantly (P < 0.01) reduced in the patients with collaterals. The septal, apical and lateral peak filling rates were also reduced in patients with collateral vessels, with the reduction in lateral peak filling rate being statistically significant (P < 0.05). The indices of systolic function and the temporal diastolic asynchronous index were similar, irrespective of the presence of collaterals. The exercise tolerance as evaluated by the rate-pressure product at peak treadmill exercise stress testing in 12 patients was significantly (P < 0.01) lower in those with collateral vessels. Angiographically visible collaterals could be a marker for more severe coronary stenosis in patients with effort-induced angina, and an indicator of the severity of deterioration in left ventricular diastolic function.

Quantitative characterization of insulin-glucose response in Watanabe heritable hyperlipidemic and cholesterol-fed rabbits and the effect of cilazapril

A great deal of evidence suggests that insulin resistance, via hyperinsulinemia, contributes to hyperlipoproteinemia and coronary atherosclerosis. When Watanabe heritable hyperlipidemic (WHHL) rabbits, an animal model of familial hypercholesterolemia (FH), are compared with normolipidemic Japanese White (JW) rabbits, an elevated fasting plasma insulin level and a heightened plasma insulin response to an intravenous (i.v.) glucose challenge are found. To elucidate the mechanism behind this phenomenon, a two-compartment model of the glucose/insulin system was fitted to empirical time courses of glucose and insulin concentrations during an i.v. glucose tolerance test (IVGTT) by nonlinear least-square regression, and the model parameters such as the glucose utilization rate constant, insulin degradation rate constant, and pancreas sensitivity were determined. WHHL rabbits showed decreased values of glucose utilization and insulin degradation rate constants and slightly higher values of pancreas sensitivity. This suggests that insulin resistance occurs in extrapancreatic tissues, and that this may be attributable to insulin receptor and/or post-insulin receptor abnormalities. Cholesterol feeding did not significantly change glucose tolerance or insulin action in JW rabbits. The effects of an angiotensin-converting enzyme (ACE) inhibitor, cilazapril, on insulin resistance were also examined in WHHL and JW rabbits. A decreased insulin response to an i.v. glucose challenge and increased glucose utilization and insulin degradation rate constants were observed in WHHL rabbits that had been treated with cilazapril, indicating that cilazapril improved insulin resistance in WHHL rabbits, possibly by increasing the number of insulin receptors. No significant differences were found in glucose tolerance and insulin action in JW rabbits before and after cilazapril administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Functional changes of dextran-modified alkaline proteinase from alkalophilic Bacillus sp

A serine alkaline proteinase (EC 3.4.21.62) from Bacillus sp. (ALPase I) was modified with the 2,4-dialdehyde derivative of clinical dextran (dialdehyde dextran). The modified preparation was purified using an ion-exchange column and gel filtration. The modified enzyme contained 75% carbohydrate by weight. The isoelectric point (pI) of ALPase I was converted from 8.2 to approximately 5.0 by this modification. The specific activity of the dextran-modified ALPase I was 56% of that of the native enzyme when milk casein was used as a substrate. It also had some superior characteristics: the thermostability of the modified enzyme at pH 10.0 was about 10-15 degrees C higher than that of control. In organic solvents such as n-hexane, benzene, and toluene, the hydrolysis reaction of the modified ALPase I for the fluorogenic substrate, succinyl-L-alanyl-L-alanyl-L-prolyl-L-phenylalanyl-4-methylcoumaryl-7-am ide (Suc-Ala-Ala-Pro-Phe-MCA), was several times higher than that of the native. This modification greatly improved the stability of ALPase I against nonionic and anionic surfactants. After exposure to lauryl benzene sulfonate and sodium lauryl sulfonate the modified enzyme retained over 95 and 90% of its activity, respectively, but the native enzyme lost its activity. We conclude that modification of serine proteinases with dialdehyde-dextran might be a useful method for improving enzyme character for enzyme technology.

In vitro conversion of recombinant human proapolipoprotein A-I to apolipoprotein A-I

We recently investigated the in vivo conversion of recombinant human proapolipoprotein A-I (rh-Met-proapo A-I) from E. coli to apolipoprotein (apo) A-I in rabbits. In vitro incubation of rh-Met-proapo A-I with rabbit serum produced mature apo A-I3 isoproteins, as determined by the immunoblotting method. However, at the time we were unable to chemically confirm a newly produced protein band which appeared at the position of human apo A-I3. Since then, we have confirmed the amino acid sequence of the protein using a membrane protein sequence technique, and have concluded that it corresponds to human apo A-I3.

Electrophysiological properties in paroxysmal atrial fibrillation complicated with the Wolff-Parkinson-White syndrome: comparison with paroxysmal atrial fibrillation alone

Electrophysiological studies were performed in 26 patients with atrial fibrillation (AF). Thirteen patients had the Wolff-Parkinson-White (WPW) syndrome (group A), and another 13 patients did not have the WPW syndrome (group B). The right atrium effective refractory period was significantly shorter in group A than in group B. The wavelength index which was defined as the ratio of the refractory period to the conduction delay was significantly lower in group A than in group B. Accordingly, patients in group A had a greater tendency to produce atrial reentry than those in group B.

Wavelength index: a predictor of the response to disopyramide in paroxysmal lone atrial fibrillation

We investigated whether the new parameter wavelength index could predict the response to chronic disopyramide therapy in patients with paroxysmal atrial fibrillation (AF). Twenty-seven patients with AF underwent electrophysiologic studies and the wavelength index was determined before and after intravenous administration of disopyramide. Then all patients were treated with oral disopyramide for 6 months. In 17 patients, AF was eliminated (group A), while it persisted in another 10 patients (group B). The ratio of the wavelength index before and after intravenous disopyramide was higher in group A than in group B. Thus, the wavelength index proved useful for predicting the response of AF to disopyramide.

Plasmin and thrombin inhibitors in essentially untreated patients with coronary artery spasm

We examined activities or levels of plasmin and thrombin inhibitors in essentially untreated patients with angiographically documented coronary artery spasm. The patients received the ergonovine malate provocation test and were classified into two groups: (a) those with significant coronary artery spasm that produced reduction of the internal luminal diameter of 50% or greater with chest pain and change of electrocardiography (n = 18), and (b) those without coronary artery spasm (n = 17). There was no significant differences in alpha 1-antitrypsin and alpha 2-macroglobulin levels, and C1-inactivator activity between the control and patients with coronary artery spasm. On the other hand, the lower antithrombin III and alpha 2-plasmin inhibitor activities were noted in patients with coronary artery spasm than the control. Thrombin/antithrombin III complex and alpha 2-plasmin inhibitor/plasmin complex levels were significantly higher in coronary artery spasm patients. These results suggest that the coagulation and fibrinolytic systems may maintain their equilibrium in untreated patients with coronary artery spasm.

Effects of calcium chloride on verapamil- and diltiazem-pretreated isolated rat hearts

The effects of calcium chloride on cardiac responses to verapamil and diltiazem were investigated using isolated and perfused rat hearts with a Langendorff technique. Ionized calcium concentrations were increased approximately from 0.5 mM to 2.2 mM when the hearts were pretreated with 0.2 mg/L of verapamil or 0.28 mg/L of diltiazem, or were untreated with calcium blockers. Calcium significantly counteracted the negative inotropic effect produced by diltiazem and verapamil. In contrast, the negative chronotropic effects of both diltiazem and verapamil were potentiated by increasing concentrations of ionized calcium, and this potentiation was not eliminated by 1.0 mg/L of atropine. An atrioventricular block was induced by both verapamil and diltiazem when ionized calcium concentrations were lower than normal. It is suggested from this study that, although calcium chloride counteracts the negative inotropic effects of verapamil and diltiazem, abruptly increased ionized calcium may cause severe bradycardia clinically.

Angioscopy in variant angina: coronary artery spasm and intimal injury

Studies in pigs and dogs show that intimal injury is related to coronary artery spasm; it is not known whether intimal injury is related to coronary artery spasm in human beings. We examined intima at the site of coronary artery spasm by percutaneous transluminal coronary angioscopy in 10 of 13 consecutive patients with variant angina. Coronary artery spasms occurred spontaneously or were induced by intracoronary acetylcholine (10-100 micrograms). Angioscopy showed intimal injuries (haemorrhage, flap, thrombus, or ulcer) in 4 of the 10. We suggest that intimal injury is related to coronary artery spasm in human beings.

Apolipoprotein(a) phenotypes and serum lipoprotein(a) levels in maintenance hemodialysis patients with/without diabetes mellitus

We studied the quantitative and qualitative characteristics of lipoprotein(a) [Lp(a)] as a function of apolipoprotein(a) [apo(a)] phenotypes in 152 patients (123 males, 29 females) undergoing maintenance hemodialysis (HD) with or without diabetes mellitus (DM), in 101 patients with diabetes mellitus without hemodialysis (58 males, 43 females), and in 421 normal controls (333 males, 88 females). Serum Lp(a) levels were significantly (P < 0.01) higher in patients than in controls (26.2 +/- 18.3 mg/dl in HD with DM, 26.4 +/- 22.0 mg/dl in HD without DM, 27.1 +/- 27.3 mg/dl in DM without HD, and 14.9 +/- 13.7 mg/dl in controls, respectively). Apo(a) phenotyping was performed by a sensitive, high resolution technique using SDS-agarose/gradient (3 to 6%) PAGE. In normal controls, the molecular weights of apo(a) isoforms were inversely correlated with plasma Lp(a) levels, and the same tendency was found in patients who were undergoing hemodialysis and/or who had diabetes mellitus. We assumed the differences in apo(a) phenotypes detectable with our method reflected consecutive differences in molecular weights of apo(a). The results of an analysis of covariance and a least square means comparison indicated that the regression lines between serum Lp(a) levels [log Lp(a)] and apo(a) phenotypes in patient groups were significantly (P < 0.01) elevated for every apo(a) phenotype, as compared to the regression line of the control group. Even after the low molecular weight apo(a) phenotypes (A1-A8) were omitted, the same tendency was observed. However, no differences were observed between the patient groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Crossover comparison between the depressor effects of low and high work-rate exercise in mild hypertension

1. The relationship between work-rate and the antihypertensive effect of exercise in hypertensives, and the mechanism of that effect, were investigated by a crossover clinical trial. 2. Ten mild hypertensives were randomly divided into two groups. One group performed low work-rate exercise (LWE) on a cycle ergometer for 10 weeks (blood lactate threshold; approximately 50% of maximum oxygen consumption [Vo2max]). After a 10 week interval without exercise training, these subjects were then switched to a high work-rate exercise (HWE) regimen (4 mmol/L of blood lactate; approximately 75% of Vo2max) for another 10 weeks. In the other group, the order of exercise training was reversed. Since two patients withdrew from the protocol during HWE periods, statistical analysis was performed on the data from the remaining eight patients. There were no order effects observed in any of the data from the two groups. 3. During both LWE and HWE, resting blood pressure (BP) fell significantly after the initiation of exercise therapy (P < 0.05). Furthermore, the overall effects of 10 weeks of LWE and HWE on BP were not significantly different. 4. The work-rate at the lactate threshold, which reflects physical fitness, had increased significantly by 16 W (P < 0.01) after the LWE period and by 11 W (P < 0.01) after the HWE. 5. During the LWE period, changes in haemodynamic and humoral variables were not significant, except for a reduction in plasma norepinephrine at week 10 (P < 0.05). In the HWE period, changes in haemodynamic and humoral variables were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)