Relationship between the administration of nicardipine hydrochloride and the development of delirium in patients on mechanical ventilation.

A history of hypertension is a known risk factor for delirium in patients in intensive care units, but the effect of antihypertensive agents on delirium development is unclear. Nicardipine, a calcium channel blocker, is widely used in ICU as a treatment agent for hypertensive emergency. This study investigated the relationship between the administration of nicardipine hydrochloride and delirium development in patients under mechanical ventilation. We conducted a medical chart review of 103 patients, who were divided into two groups according to the use of nicardipine hydrochloride. The prevalence of delirium was compared with respect to factors such as age, sex, laboratory data, and medical history, by multivariate analysis. 21 patients (20.4 %) were treated with nicardipine hydrochloride in 103 patients. The treatment and non-treatment groups differed significantly in age (72 vs. 65 years) and history of high blood pressure (57% vs. 11%). Multivariate analysis revealed that patients in the treatment group developed delirium significantly less often than those in the non-treatment group (19% vs. 48%). These results suggested that treatment of high blood pressure with nicardipine hydrochloride is a possible method for preventing the development of delirium.

Five-band microwave radiometer system for non-invasive measurement of brain temperature in new-born infants: system calibration and its feasibility.

Recent simulation studies have shown that a technique of multi-frequency microwave radiometry is feasible for non-invasive measurement of deep brain temperatures in the new-born infants. A five-band microwave radiometer system has been developed, and its operation in a normal electromagnetic environment is checked. Five receivers operating with a waveguide antenna and at center frequencies of 1.2, 1.65, 2.3, 3.0 and 3.6 GHz (0.4 GHz bandwidth) are calibrated using a temperature-controlled water-bath. Temperature resolutions obtained for each receiver are 0.183, 0.273, 0.148, 0.108 and 0.118 K, respectively. A temperature retrieval simulation based on these resolutions and the previously proposed algorithm shows that the confidence interval, as produced by thermal noise, is 0.62 K for the retrieved central brain temperature. If the conductivity of brain is estimated wrong by 10 %, this will result in an error of 0.3-0.4 K. The result of this work is encouraging for realization of radiometric measurement of temperature profile in a baby's head.

Diabetes mellitus prevents ischemic preconditioning in patients with a first acute anterior wall myocardial infarction.

OBJECTIVES: This study was undertaken to assess whether prodromal angina could have beneficial effects in diabetic patients with acute myocardial infarction (AMI). BACKGROUND: Prodromal angina occurring shortly before the onset of AMI is associated with favorable outcomes by the mechanism of ischemic preconditioning. However, little is known about the impact of diabetes on ischemic preconditioning. METHODS: We studied 611 patients with a first anterior wall AMI who underwent emergency catheterization within 12 h after the onset of chest pain: 490 patients without diabetes and 121 patients with non-insulin treated diabetes. Prodromal angina was defined as angina episode(s) occurring within 24 h before the onset of AMI. Serial contrast left ventriculograms were obtained in 424 patients at the time of acute and predischarge catheterization. RESULTS: In non-diabetic patients, prodromal angina was associated with lower peak creatine kinase (CK) value (3,068 +/- 2,647 IU/l vs. 3,601 +/- 2,462 IU/l, p = 0.037), larger increase in left ventricular ejection fraction (LVEF) (10.1 +/- 13.0% vs. 5.8 +/- 13.4%, p = 0.004) and lower in-hospital mortality (3.4% vs. 9.3%, p = 0.015). On the contrary, in diabetic patients, there was no significant difference in peak CK value (3,382 +/- 2,520 IU/l vs. 3,233 +/- 2,412 IU/l, p = NS), the change in LVEF (6.7 +/- 13.8% vs. 7.1 +/- 12.4%, p = NS) and in-hospital mortality (8.8% vs. 11.0%, p = NS) between patients with and patients without prodromal angina. CONCLUSIONS: Prodromal angina limited infarct size, enhanced recovery of LV function and improved survival in non-diabetic patients with AMI. However, such beneficial effects of prodromal angina were not observed in diabetic patients, suggesting that diabetes might prevent ischemic preconditioning.

Impact of diabetes mellitus on long term survival after acute myocardial infarction in patients with single vessel disease.

OBJECTIVE: To assess the influence of diabetes on long term prognosis after reperfusion treatment and its interaction with multivessel disease. DESIGN: A retrospective observational study. SETTING: Hiroshima City Hospital. PATIENTS: 1660 consecutive patients with acute myocardial infarction who underwent coronary angiography within 24 hours after the onset of chest pain. MAIN OUTCOME MEASURES: Influence of diabetes on 10 year survival after infarction was assessed using the generalised Wilcoxon test and Cox's proportional hazards regression. Follow up was completed in 1622 patients (98%). RESULTS: Diabetic patients had more multivessel disease than non-diabetic patients (53% v 34%, p < 0.001). When only patients with single vessel disease were compared, diabetes was associated with a reduced 10 year survival after infarction (p = 0.002). On the other hand, in patients with multivessel disease there was no significant difference in survival between diabetic and non-diabetic patients (p = 0.70). Multivariate analysis also showed that diabetes was an independent risk factor related to 10 year mortality after infarction in patients with single vessel disease (odds ratio (OR) 1.81, 95% confidence interval (CI) 1.27 to 2.54; p = 0.001) and not in patients with multivessel disease (OR 1.17, 95% CI 0.85 to 1.60; p = 0.34). CONCLUSIONS: Diabetes is an independent predictor of long term mortality after infarction in patients with single vessel disease. However, in the presence of multivessel disease, prognosis after infarction is impaired regardless of diabetes, and the influence of diabetes is less obvious.

A novel nuclear phosphoprotein, GANP, is up-regulated in centrocytes of the germinal center and associated with MCM3, a protein essential for DNA replication.

Antigen (Ag) immunization induces formation of the germinal center (GC), with large, rapidly proliferating centroblasts in the dark zone, and small, nondividing centrocytes in the light zone. We identified a novel nuclear protein, GANP, that is up-regulated in centrocytes. We found that GANP was up-regulated in GC B cells of Peyer's patches in normal mice and in spleens from Ag-immunized mice. GANP-positive cells appeared in the light zone of the GC, with coexpression of the peanut agglutinin (PNA) (PNA)-positive B220-positive phenotype. The expression of GANP was strikingly correlated with GC formation because Bcl6-deficient mice did not show the up-regulation of GANP. GANP-positive cells were mostly surrounded by follicular dendritic cells. Stimulation with anti-micro and anti-CD40 induced up-regulation of ganp messenger RNA as well as GANP protein in B220-positive B cells in vitro. GANP is a 210-kd protein localized in both the cytoplasm and nuclei, with a homologous region to Map80 that is associated with MCM3, a protein essential for DNA replication. Remarkably, GANP is associated with MCM3 in B cells and MCM3 is also up-regulated in the GC area. These results suggest that the up-regulation of GANP might participate in the development of Ag-driven B cells in GCs through its interaction with MCM3.

[Suppression of conditioned fear by administration of CCKB receptor antagonist PD135158].

The aim of this study is to determine whether or not CCKB receptor antagonist PD135158 suppresses conditioned fear. Rats were individually subjected to 30 min of inescapable electric footshock in a chamber with a grid floor. PD135158 or the vehicle was administered 30 min before placing the rats in the shock chamber again. The rats were observed for 5 min without receiving shock. The administration of PD135158 30 min before conditioned-fear stress significantly reduced freezing behavior. PD135158 blocked the expression of conditioned fear. PD135158 was again administered 30 min before footshock. Then, the rats were individually subjected to 30 min of inescapable electric footshock in the shock chamber. Twenty-four hours after receiving footshock, the rats were again placed in the shock chamber and observed for 5 min without shock administration. The administration of PD135158 30 min before footshock significantly reduced conditioned freezing. PD135158 blocked the anxiety of conditioned fear. PD135158 blocked not only the anxiety, but also the expression of conditioned fear. These results suggest that CCKB receptor might play an important role in conditioned-fear stress. They indicate that CCKB receptor is related to anxiety.

Extrashot-ODS, a syringe-type minicolumn sample injector for a reversed-phase high-performance liquid chromatographic column. Application to antiepileptics in human sera.

Extrashot-ODS (EXS-ODS) is a syringe-type minicolumn developed for sample injection into reversed-phase high-performance liquid chromatographic columns. EXS-ODS consists of (a) a stainless-steel needle fitted to an ordinary syringe-loading sample injector for HPLC, (b) a 45-microl minicolumn tube made of polytetrafluoroethylene (PTFE) and packed with ODS-silica and (c) a minicolumn holder made of polystyrene, which is connected to the needle on one side and the other side is shaped so as to be fitted with a solvent syringe. Using the device, we simultaneously analyzed three antiepileptics in 20 microl of human sera. First, we introduced a 20-microl serum specimen diluted with 100 microl of buffer solution into the device and, second, 100 microl of distilled water. Then the device was attached to the HPLC injector and 130 microl of methanol were introduced into the HPLC column through the device. Then, reversed-phase HPLC was conducted in the usual manner, with the chromatogram reading at a wavelength of 210 nm for the assays of 5,5-diphenylhydantoin, phenobarbital and carbamazepine. The results obtained by direct peak-height calibration were comparable to those given by the immunological method.

[Development of syringe-type off line pre-column and simultaneous quantitation of four xanthine derivatives (caffeine, theobromine, theophylline and paraxanthine) in serum].

A new syringe-type minicolumn, called Extrashot-Silica (EXS-Silica), containing diatomaceous earth granules was described. The EXS-Silica differs from the conventional pretreatment column. Using the EXS-Silica we can execute the simultaneous extraction-injection to HPLC, column. Therefore, an analysis using the EXS-Silica is an easier and faster method than the general HPLC analysis method. In this study, we carried out the simultaneous determination of four xanthine derivatives, such as caffeine, theobromine, theophylline and paraxanthine, in serum specimens. We used dichloromethane containing 4% ethanol (v/v) for the extraction-injection and water-acetic acid-ethanol-dichloromethane (0.2:0.2:4:95.6, v/v) for the mobile phase of HPLC. The eluent was monitored with a UV detector at 275 nm. A linear relationship between the amount of drug and the peak height was confirmed in the range of 1-40 micrograms/ml for the above-mentioned four xanthine derivatives in the serum. When a 5 microliters aliquot of the serum was subjected to this method, the observed detection limits of the drug were far less than therapeutic concentrations. The analytical accuracy of our method was finally confirmed by comparing the obtained analytical data by the new method with those obtained using the fluorescense polarization immunoassay method. Serum concentrations of theophylline obtained by these two methods correlate satisfactorily. Except for minor modifications in the injector, the existing liquid-chromatographic equipment can be used.

[Endothelin-1 levels in sputum and plasma of asthmatic patient after allergen provocation].

Recently, endothelin-1 (ET-1) has a potent of contractive effect to bronchial smooth muscle, and it suggests that ET-1 contributes to pathophysiology of bronchial asthma. To study the role of endothelin-1 (ET-1) in allergic asthma, we measured ET concentration in plasma and in sputum of nine allergic subjects following allergen provocation by using sandwich-enzyme immunoassay (EIA). ET-1 concentration in plasma were higher during IAR (2.31 +/- 0.24 pg/ml) (0.05 < p < 0.1) and LAR (2.55 +/- 0.27 pg/ml) (0.05 < p < 0.1) than prechallenge value (1.99 +/- 0.23 pg/ml) but there was no significant difference. On the other hand ET-1 concentration in sputum were significantly higher during IAR (14.75 +/- 2.77 pg/ml) (p < 0.05) and LAR (18.51 +/- 4.57 pg/ml) (p < 0.05) than prechallenge values (4.29 +/- 2.55 pg/ml). Thus these results suggest that ET-1 play a role of allergic bronchoconstraction (IAR and LAR) after allergen challenge.

[Limb myokymia with involuntary finger movement caused by peripheral neuropathy due to systemic lupus erythematosus (SLE)--a case report].

A 24-year-old woman with SLE since the age of 12 developed sensory-motor peripheral neuropathy in 1990. Her sensory neuropathy was symmetrical in all limbs and distally dominant. Electrophysiological study showed marked reduction of motor and sensory conduction velocities. Sural nerve biopsy revealed vasculitis and axonopathy. Symptoms of neuropathy and nerve conduction velocities were improved by high dose steroid treatment. After one year she had a fever of unknown origin, and then presented limb myokymia with involuntary finger movement which was fine, irregular, and continuous. Needle EMG revealed myokymic discharge at dorsal interosseous and flexor pollicis brevis muscles. Because myokymia was increased by hyperventilation and suppressed by local anesthesia at the wrist, her myokymia was thought to originate in the peripheral nerve. This is the first case report of limb myokymia with finger involuntary movement caused by peripheral neuropathy due to SLE.

Simple and accurate high-performance liquid chromatographic method for the measurement of three antiepileptics in therapeutic drug monitoring.

A high-performance liquid chromatographic method for simultaneous determination of three antiepileptics, phenytoin, phenobarbital, and carbamazepine, in serum for therapeutic drug monitoring is described. The drugs were extracted and injected onto a silica-gel column using a syringe-type minicolumn, Extrashot-Silica, packed with diatomaceous earth granules. We used dichloromethane for extraction-injection and n-hexane containing 0.2% acetic acid, 2% ethanol, and 15% dichloromethane for the mobile phase of a silica-gel HPLC. The eluent was monitored with a UV detector set at 240 nm. Linear relationships between the amount of drug and peak height were confirmed at 1-20 micrograms/ml in serum for carbamazepine and 5-40 micrograms/ml in serum for phenytoin and phenobarbital. When a 5-microliters aliquot of serum was subjected to this method, the observed detection limits of the drugs were far less than therapeutic concentrations. Thus, our method was simple and accurate enough to be used in routine therapeutic drug monitoring and basic pharmacokinetic studies.

Change in responsiveness of airway and beta-adrenoceptor in guinea pigs.

Allergen inhalation challenge resulted in significant (p < 0.05) increase in airway responsiveness to methacholine soon after immediate airway response (IAR) in guinea pigs actively sensitized with inhaled ovalbumin (OA) in vivo. We have investigated the involvement of thromboxane (Tx) A2 and platelet activating factor (PAF) in this airway hyperresponsiveness (AH). Pretreatment with CS-518, a selective thromboxane synthetase inhibitor, significantly inhibited both IAR (p < 0.07) and AH (p < 0.01), while pretreatment with WEB 2086, a PAF receptor antagonist, significantly inhibited only IAR (p < 0.05), but not AH after IAR. Propranolol, when inhaled before OA exposure, had no effect on bronchomotor tone, but if inhaled after IAR, it caused immediate death of guinea pigs. This result suggests that hyperresponsiveness of beta-adrenoceptor to propranolol may be induced by IAR. Examination of bronchoalveolar lavage (BAL) fluid revealed that no changes in cellular content were observed 60 min after OA exposure. In vitro, responsiveness of tracheal smooth muscle to carbachol was not changed by sensitization. Furthermore, anaphylactic reaction in vitro had no effect on the responsiveness. We conclude that airway responsiveness increases soon after IAR when infiltration of inflammatory cells is not yet found in vivo. It is also suggested that TxA2 but not PAF is involved in AH. Hyperresponsiveness to propranolol after IAR in OA sensitized guinea pigs illustrates the possibility of changes in function of beta-adrenoceptor after IAR.

Simple and accurate determination of methylpyrazines in biofluids using high-performance liquid chromatography.

The determination of six methylpyrazines was performed using high-performance liquid chromatography (HPLC). Methylpyrazines were simultaneously extracted and injected onto a silica gel column with a syringe-type minicolumn packed with diatomaceous earth granules. The extraction-injection solvent used was dichloromethane and the mobile phase solvent for HPLC was dichloromethane containing 0.08% of 1.65 M ammonia solution and 0.5% of methanol. Methylpyrazines were detected using an ultraviolet detector set at 275 nm. Linear relationships between the amount of sample and peak height were confirmed from 50 ng/ml to 10 micrograms/ml of the biofluids. When an aliquot of 10 microliters of biofluid was introduced to the minicolumn, the detection limit of methylpyrazines was as low as 30 ng/ml with each pyrazine derivative. The method is simple and accurate and is thus applicable to pharmacokinetic studies which are performed on animals. The results showed that the possible pharmacological effects of methylpyrazines might be evaluated pharmacokinetically using this newly developed technique.

Molecular cloning and nucleotide sequencing of the Arthrobacter dextranase gene and its expression in Escherichia coli and Streptococcus sanguis.

A bacterial strain, which assimilated dextran and water-insoluble glucan produced by Streptococcus mutans, was isolated from soil. The bacterium produced and secreted potent dextranase activity, which was identified as Arthrobacter sp. and named CB-8. The dextranase was purified and some enzymatic properties were characterized. The enzyme efficiently decomposed the water-insoluble glucan as well as dextran. A gene library from the bacteria was constructed with Escherichia coli, using plasmid pUC19, and clones producing dextranase activity were selected. Based on the result of nucleotide sequencing analysis, it was deduced that the dextranase was synthesized in CB-8 cells as a polypeptide precursor consisting of 640 amino acid residues, including 49 N-terminal amino acid residues which could be regarded as a signal peptide. In the E. coli transformant, the dextranase activity was detected mostly in the periplasmic space. The gene for the dextranase was introduced into Streptococcus sanguis, using an E. coli-S. sanguis shuttle vector that contained the promoter sequence of a gene for glucosyltransferase derived from a strain of S. mutans. The active dextranase was also expressed and accumulated in S. sanguis cells.

Biomechanical study on monocortical osteosynthesis for the fracture of the mandible.

In order to compare the rigidity of the fixation and resultant bone healing of monocortical versus bicortical osteosynthesis, biomechanical tests were performed in dogs. Use of a gnathotome made it possible to produce a mandibular fracture with minimal bone defect between fragments. An AO dynamic compression plate and a mini-plate were used for the fixation of each half side of the fractured mandible. The biomechanical tests revealed that bicortical osteosynthesis was superior to monocortical in the rigidity of the fixation. However, the results after removal of the plates, at 14 weeks postoperatively, showed that there was no apparent difference between the 2 sides. Monocortical osteosynthesis is useful in the treatment of mandibular fractures, except for fractures with bone defects, comminuted fragments and laceration of the lateral cortical bone.

Use of lyophilized porcine skin to the oral wound. Clinical application and experimental evaluation as a temporary dressing material.

In order to cover the defect of the oral mucosa temporarily, we used lyophilized porcine skin (LPS) in 10 cases. The use of LPS seemed to be effective from the following points of view; alleviation of postoperative pain and as a protection against exogenous irritants. A fixation method, that is, a continuous locked suture, was devised technically to prevent the LPS from tearing by suturing. With this simple method, the patient maintained good oral hygiene and had only a slight discomfort. Histological examination using Japanese white rabbits showed no apparent difference in wound healing between this method and interrupted suture with tie-over compression. Re-epithelialization of the wound in the non-dressed (control) group was recognized earlier than that in the LPS-covered group.