Prepulse-induced mode 2 gating behavior with and without beta-adrenergic stimulation in cardiac L-type Ca channels

Mode 2 gating of L-type Ca channels is characterized by high channel open probability (NPo) and long openings. In cardiac myocytes, this mode is evoked physiologically in two apparently different circumstances: membrane depolarization (prepulse facilitation) and activation of protein kinase A. To examine whether the phosphorylation mechanism is involved during prepulse-induced facilitation of cardiac L-type Ca channels, we used isolated guinea pig ventricular myocytes to analyze depolarization-induced modal gating behavior under different basal levels of phosphorylation. In control, NPo measured at 0 mV was augmented as the duration of prepulse to +100 mV was prolonged from 50 to 400 ms. This was due to the induction of mode 2 gating behavior clustered at the beginning of test pulses. Analysis of open time distribution revealed that the prepulse evoked an extra component, the time constant of which is not dependent on prepulse duration. When isoproterenol (1 microM) was applied to keep Ca channels at an enhanced level of phosphorylation, basal NPo without prepulse was increased by a factor of 3.6 +/- 2.2 (n = 6). Under these conditions, prepulse further increased NPo by promoting long openings with the same kinetics of transition to mode 2 gating (tau congruent with 200 ms at +100 mV). Likewise, recovery from mode 2 gating, as estimated by the decay of averaged unitary current, was not affected after beta-stimulation (tau congruent with 25 ms at 0 mV). The kinetic behavior independent from the basal level of phosphorylation or activity of cAMP-dependent protein kinase suggests that prepulse facilitation of the cardiac Ca channel involves a mechanism directly related to voltage-dependent conformational change rather than voltage-dependent phosphorylation.

Potentiation of recombinant L-type Ca channel currents by alpha1-adrenoceptors coexpressed in baby hamster kidney (BHK) cells

In cardiac myocytes, the effect of alpha1-adrenergic stimulation on L-type Ca current remains to be clarified. We examined this issue by the transient coexpression of alpha1-adrenoceptors on BHKC12 cells, where recombinant Ca channels composed of cardiac alpha1 subunit and skeletal beta, gamma, alpha2/delta subunits were stably expressed. After transfection of plasmid DNA encoding bovine alpha1C-adrenoceptors, bath-applied phenylephrine potentiated the cloned Ca channel current during perforated-patch whole-cell recording by 26+/-6% in 6 out of 12 cells. The potentiation was elicited also by methoxamine, and was blocked by prazosin. Phenylephrine also increased the channel open probability during cell-attached single channel recording in 7 out of 15 cells. The ratio of successful modulation of Ca channels was in accordance with the ratio of successful expression of alpha1-adrenoceptors, as estimated by beta-galactosidase staining. These results suggest that the stimulation of alpha1C-adrenoceptors is linked to potentiation of cardiac L-type Ca current. BHK cells provide a valuable expression system to study the modulation of Ca channels evoked by a receptor stimulation.

208-W TEM00 operation of a diode-pumped Nd:YAG rod laser

208-W average-power TEM(00) -mode operation from a diode-pumped Nd:YAG rod laser was demonstrated. The side-pumping method of generating a high-gain aberration-free rod, the bifocusing-compensation technique with two identically pumped rods, and a suitable choice of beam spot size were employed in the design of this laser. At the maximum pump power of 1.1 kW the fundamental transverse-mode operation (M(2)<1.1) was characterized by 7.6% electrical efficiency. The extraction efficiency was almost 60% of full multimode operation. Stable operation was obtained within a pump-power range of 15% of the maximum pump power.

Preparation of poly(ethylene glycol)-polystyrene block copolymers using photochemistry of dithiocarbamate as a reduced cell-adhesive coating material

This article reports a novel preparation method of poly(ethylene glycol) (PEG)-polystyrene (PST) amphiphilic block copolymers with well-defined block lengths by using photopolymerization of an iniferter, benzyl N,N-diethyldithiocarbamate. PEG macroiniferters, which were prepared by end-capping of PEG monomethyl ethers with benzyl N,N-diethyldithiocarbamate group at one end, were irradiated with UV light in the presence of styrene (ST). NMR analyses showed that the PST block was chain-extended from the PEG block, resulting in the preparation of PEG-PST block copolymers. The number-average molecular weights of the copolymers increased almost linearly with irradiation time, light intensity, and concentration of ST. The polydispersities of the copolymers remained relatively small throughout the reaction (Mw/Mn approximately 1.3). The composition of two PEG-PST block copolymers thus obtained was as follows: PEG (Mn; 1.9 x 10(3) gmol(-1))-PST (3.0 x 10(3) gmol(-1)) and PEG (4.9 x 10(3) gmol(-1))-PST (2.6 x 10(3) gmol(-1)). These copolymers were coated onto a poly(ethylene terephthalate) film surface. X-ray photoelectron spectroscopy analyses and water wettability measurements showed that the PST block was enriched at the outermost layer as cast in air, whereas upon immersion into water, the PEG block was oriented toward water. Enhanced wettability was observed for the diblock copolymer with a higher PEG content. Significantly reduced cell adhesion was observed on both the coated surfaces. Thus, the PEG-PST block copolymer may function as a cell adhesion-resistant coating which reduced cell-substrate interaction.

A new, simple method for measuring mucociliary clearance in guinea-pigs

Airway mucociliary transport (MCT), which continuously removes inhaled particles and cellular debris from deep in the lung, is impaired in a number of diseases such as bronchitis and asthma. In order to determine the effects of candidate drugs on MCT function in the airway, a new in situ method to measure MCT function was established. MCT function is represented by the distance a gelatin solution containing Evans blue as a marker moves after injection into the trachea. The basal rate of dye transport in non-treated guinea-pigs was 4.4+/-0.2 mm/min. The beta2-adrenoceptor agonist salbutamol (2, 6, 10, 20 mg/kg, po), dose-dependently accelerated the basal MCT rate. However, its effect was completely inhibited by pretreatment with the non-selective beta -adrenoceptor antagonist, propranolol (1 mg/kg, iv). MCT function in guinea-pigs was significantly attenuated to 2.6+/-0.3 mm/min by SO2 gas exposure. Salbutamol failed to prevent MCT dysfunction in SO2-exposed animals at doses previously shown to accelerate basal MCT rate. This simple method is useful for estimating MCT function in several airway disease models and for examining new drugs designed to improve MCT function in airway diseases.

Emergence and spread of a new clone of M type 1 group A Streptococcus coincident with the increase in invasive diseases in Japan

BACKGROUND

In Japan invasive group A streptococcal infections such as sepsis and toxic shock syndrome (TSS) have increased since 1992. As is the case in the United States and Europe, M1 serotype is predominant among the isolates from Japanese patients.

METHODS

By restriction enzyme digestion and pulsed field gel electrophoresis, we investigated the whole genomic DNA profiles of 95 M type 1 group A streptococcal strains isolated from patients with serious diseases including sepsis, toxic shock syndrome, necrotizing fasciitis and nonsuppurative complications and with uncomplicated pharyngitis during 1979 through 1996 in Japan.

RESULTS

The genome profiles among 8 of 10 isolates from patients with serious diseases in 1979 through 1991 were all the same and were shared by the profiles of the 35 of 48 isolates from patients with uncomplicated pharyngitis in 1982 through 1991. All 18 strains isolated from patients with invasive diseases in 1992 to 1996 had a unique profile, which was shared by the profiles of 18 of 19 isolates from uncomplicated pharyngitis during the same period. This genomic profile was distinct from the predominant or any other profiles before 1992, and it was found to be a new clone.

CONCLUSIONS

The emergence and spread of this new clone of M type 1 Streptococcus after 1991 may be associated with the increase in invasive streptococcal infections that occurred during the same period in Japan. Genomic profiles as well as serotypes of streptococcal isolates are important for the epidemiology of clinical relevance in streptococcal diseases.

MR imaging of hepatic injury in the LEC rat under a high magnetic field (7.05 T)

Visualization of copper-induced hepatitis (CuH) in LEC rats was performed by using an MRI apparatus equipped with a magnet producing a high magnetic field of 7.05 T. When three groups of LEC rats (6-16 [pre-hepatitis], 15-26 [acute hepatitis] and 40-77 [chronic hepatitis] weeks old) were examined by MRI under T2-weighted imaging conditions which are suitable for the diagnosis of human hepatitis, hypointense MR images of the livers were, as a whole, obtained in all groups, suggesting that these conditions were not adequate for imaging of CuH of LEC rats. The shortening of the T1 and T2 relaxation times of livers due to an excess amount of paramagnetic irons under the high magnetic field was responsible for the lowering of MR signal intensities of the livers, especially those of 15 to 26-week old rats showing acute hepatitis. However, theoretical calculation of the MR signal intensities using the T1 and T2 relaxation times of the livers indicated that their imaging might be possible under proton density-weighted conditions even with a high magnetic field. Experimental results showed that hepatic injury was visualized as hyperintense regions in the MR image of the liver in the acute-phase rat.

Effect of overproduction of interleukin 5 on dinitrofluorobenzene-induced allergic cutaneous response in mice

The effect of overproduction of interleukin (IL) 5 on the allergic cutaneous response was investigated in transgenic mice overexpressing IL-5. Five repeated topical applications of 2, 4-dinitrofluorobenzene (DNFB) to the ears of mice resulted in allergic dermatitis on the ears as well as significant elevation in dinitrophenol-specific IgE antibody and total IgE in the serum in both wild-type and transgenic mice. The development of dermatitis as measured by skin thickness and histopathological changes were potentiated in the transgenic mice. In IL-5 transgenic mice, significant accumulation of eosinophils in skin lesions was observed after five paintings of DNFB, and the magnitudes of eosinophilia and IL-5 messenger RNA expression were significantly higher than in wild-type mice. The dinitrophenol-specific and total IgE in the serum were higher in IL-5 transgenic mice. The late phase reaction of IgE antibody-mediated biphasic cutaneous response was potentiated in IL-5 transgenic mice. The magnitudes of vasopermeability increase by passive cutaneous anaphylaxis, serotonin, and platelet-activating factor were similar in both mice. These results indicate that overproduction of IL-5 resulted in the potentiation of DNFB-induced dermatitis by elevation of IgE production, IgE-mediated allergic late-phase cutaneous reaction, and eosinophilia in the skin lesion.

The change of bone mineral density in secondary osteoporosis and vertebral fracture incidence

Causes of secondary osteoporosis are diverse, and bone changes in this condition have been elucidated less than those in primary osteoporosis. In this study, bone mineral density (BMD) was measured in the lumbar spine, distal and proximal sites of the radius, and calcaneus in representative disorders that cause secondary osteoporosis to evaluate its changes. Also, the incidence of nontraumatic vertebral fracture was examined. The subjects were 80 patients with rheumatoid arthritis, 50 patients undergoing glucocorticoid (steroid) therapy, 20 patients with chronic hepatitis, 24 patients with liver cirrhosis, 14 patients with primary biliary cirrhosis (PBC), 26 patients with diabetes mellitus, and 20 postgastrectomy patients; all were ambulatory female outpatients. Two hundred females with primary osteoporosis were examined as a control group. The reproducibility of the measurement of the BMD was satisfactory at about 3% by all methods of measurement employed. Concerning changes in BMD, periarticular trabecular bone density was most markedly reduced in the rheumatoid arthritis group. The patients receiving steroid therapy showed the greatest decreases in the trabecular bone mineral density at the distal 4% of the radius and lumbar spinal BMD. In addition, the threshold of vertebral fracture was higher in those undergoing steroid therapy than in those with primary osteoporosis. The patients with PBC showed the greatest decreases in BMD among patients with chronic liver disorders, and no decrease in BMD was noted in the chronic hepatitis group. BMD was reduced only in the radius in the patients with diabetic mellitus, and it was generally reduced in the postgastrectomy patients. BMD of the calcaneus was not reduced in any group.

[Extended resection of the great vessels for primary lung cancer and mediastinal tumor]

From 1973 to 1998, we resected and reconstructed the great vessels in 44 patients with primary lung cancer or mediastinal tumor. Among them, 39 patients (28 with lung cancer and 11 with mediastinal tumor) and 5 patients (all with lung cancer) underwent reconstruction of the superior vena cava (SVC) and aorta, respectively. The SVC was repaired by expanded polytetrafluoroethylene (EPTFE) graft (n = 8), prosthetic patch (n = 5) or direct suture (n = 26). The aorta was repaired with temporary subclavian artery-descending aorta (n = 3), or left atrium-femoral artery bypass (n = 2). No complication or operative death occurred after surgery. The survival rate of the patients with lung cancer who underwent SVC reconstruction at 3 year and 5 year were 26.2% and 11.2%, respectively. Five of 11 (45.5%) patients with mediastinal tumor are alive at 5 years. We concluded that extended resection for primary lung cancer or mediastinal tumor invading the SVC is acceptable operation method for some patients.

[Monozygotic twins with suspected hereditary sensory and autonomic neuropathy (HSAN) type V]

We report a pair of 1-year-5-month-old female monozygotic twins with generalized loss of pain sensation, but without impairment of other sensory modalities and the diaphoretic function. Routine electrophysiological investigations revealed no abnormalities. Morphometric analysis of biopsied sural nerve showed that the number of small myelinated fibers was reduced and that of unmyelinated fibers was normal or mildly reduced. On the basis of these findings, we suspected a diagnosis of a rare disorder, HSAN type V, which has not previously been reported in Japan.

[Endothelial-derived nitric oxide mediates the peripheral vasodilatory effects of amrinone in humans]

Amrinone, which is used for the treatment of acute congestive heart failure, has vasodilatory and positive inotropic effects through the increment of intracellular cyclic adenosine monophosphate. Recent in vitro investigations have shown that amrinone has an endothelium-dependent vasodilatory effect. The present study examined whether amrinone shows this endothelium-dependent vasodilatory effect in human peripheral vessels. Forearm blood flow during intra-arterial infusion of graded doses (12.5, 25, 50, 100, 200 micrograms/min) of amrinone was measured using plethysmography in 10 healthy subjects without organic vascular disease before and after nitric oxide synthase blocking with NG-monomethyl-L-arginine (L-NMMA, 400 mumol). The graded dose of amrinone produced progressive increases in amrinone plasma concentrations, and a dose over 100 micrograms/min caused amrinone plasma concentrations of more than 1.0 microgram/ml. The increase in forearm blood flow in response to amrinone was significantly depressed after L-NMMA doses of less than 100 micrograms/min, but the increase in forearm blood flow during infusion of higher doses (100, 200 micrograms/min) was not affected by L-NMMA. These results suggest that endothelial-derived nitric oxide may partially contribute to amrinone-induced vasodilation in humans. Thus, the vasodilatory effect of amrinone might be impaired in patients with endothelial dysfunction.

Structures of P-type transporting ATPases and chromosomal locations of their genes

P-type ATPases (E1E2-ATPases) are primary active transporters which form phospho-intermediates during their catalytic cycle. They are classified into P1 to P4 based on the primary structure and potential transmembrane segments. Although the classic P-type ATPases are cation transporters, two new members have recently been found; one is a flippase catalyzing the flip-flop movement of aminophospholipids, but the substrate and function of the other one remain unknown. It would be interesting to determine whether the cations and aminophospholipids are transported by similar or different mechanisms. P-type ATPases are believed to have been derived from a common ancestor, and their genes are found to be distributed in various chromosomal loci. However, gene duplication events can be traced from the tandem arrangement of genes and their linkage map. Na+/K+- and H+/K+-ATPases have not only closely related a subunits but also similar beta subunits. Renal Na+/K+-ATPase has an additional subunit gamma. Similar small polypeptides (phospholemman, Mat-8 and CHIF), which induce Cl- and K+ currents, have been found. The idea of their functional and structural coupling with P-type ATPases, especially with H+/K+-ATPase, is intriguing. Each P-type ATPase must have specific domains or sequences for its intracellular trafficking (sorting, retention and recycling). Identification of such regions and studies on the molecules playing role in their recognition may facilitate the unveiling of various cellular processes regulated by P-type ATPases.

Effects of alpha1-adrenergic stimulation on L-type Ca2+ current in rat ventricular myocytes

The effect of alpha1-adrenergic stimulation on L-type Ca2+ current (ICa,L) in adult rat ventricular myocytes was investigated using three different methods of current recording. During conventional whole-cell recordings with 5 mm-BAPTA included in the pipette solution, phenylephrine (20 microM) did not increase ICa,L after 10 min of application. With nystatin perforated-patch whole-cell recordings, phenylephrine potentiated ICa,L, although there were variations among myocytes. The most frequent response was a transient suppression of peak ICa,L at approximately 2 min of exposure followed by a sustained increase of current amplitude evident after 5-10 min exposure. The relative current amplitude 10 min after phenylephrine application was 1.08+/-0.05 compared to control (n=14 cells,P<0.05). During cell-attached single channel recordings, phenylephrine (1 microM) increased the L-type Ca2+ channel open probability (NPo) by 2.25+/-0.31-fold (n=21,P<0.01). It potentiated NPo by increasing the number of openings per sweep and also by promoting longer openings. These effects developed slowly in approximately 10 min. Phenylephrine had no on unitary current amplitude. The potentiation was also elicited by methoxamine (5 microM) and was blocked by prazosin (1 microM), indicating that it was mediated by alpha1-adrenergic receptor stimulation. The increase in NP(o) was suppressed by chelerythrine, a protein kinase C inhibitor. Our results demonstrate that ICa,L can be enhanced by alpha1-adrenergic stimulation, and stress the importance of not disturbing the intracellular environment during studies of the modulation of cardiac ICa,L by alpha1-adrenergic stimulation.

Role of cardiac chloride currents in changes in action potential characteristics and arrhythmias

Various types of Cl- currents have been recorded in cardiac myocytes from different regions of the heart and in different species. With few exceptions, most of these currents are not active under basal conditions, but are activated under the influence of various agonists and by physical stress. These channels are distributed nonuniformly, depending on the cell type, tissue and region of the heart. Therefore, Cl- current activation may influence membrane potential and impulse formation differently in different cells, and may play a role in arrhythmogenesis. Among these Cl- currents, the protein kinase A-activated Cl- current (I Cl.PKA), the stretch- or swelling-activated Cl- current (I Cl.SWELL) and the Ca(2+)-activated Cl current (I Cl.Ca) comprise the major anion currents that modify cardiac electrical activity. These currents exhibit outward-going rectification, or are predominantly activated at depolarized voltages and, thus, contribute significantly to shortening of the action potential duration but little to diastolic depolarization. The action potential shortening by Cl- current activation may not only perpetuate reentry by shortening the refractory period in a reentry pathway, but may also prevent the development of early afterdepolarization and triggered activity caused by the prolongation of action potentials. I Cl.Ca contributes to delayed afterdepolarization at diastolic potentials in Ca(2+)-overloaded cells. Another factor limiting the influence of Cl- currents on diastolic potentials is the presence of a predominantly opposing background K+ current, except at the nodal regions that lack these K+ channels, or under conditions of decreased K+ conductance. Therefore, the contribution of Cl- currents to the genesis of arrhythmias may depend on their association with the conductance of other ions, especially that of K+.

Therapeutic results of intra-arterial chemotherapy in patients with malignant glioma

Thirty-three adult patients with anaplastic astrocytoma or glioblastoma multiforme, verified between 1990 and 1997, received postoperative intra-arterial ACNU chemotherapy and irradiation. Since our previous strategies to malignant gliomas had included intra-venous ACNU, the purpose of the present study is to evaluate the advantage of intra-arterial ACNU over its intra-venous counterpart as the historical control (37 patients). The median survival was 74.7 weeks for the former and 81.7 weeks for the latter. Although both groups were equivalent in survival, toxicity was less frequent in the intra-arterial group. Histopathological diagnosis, patient age and the Karnofsky's performance status related well with the survival.

Telomerase activity as an indicator of potentially malignant adrenal tumors

BACKGROUND

Telomerase is an enzyme that adds repeated telomere sequences to the ends of chromosome arms. It helps maintain both the length of telomere and infinite cell proliferation. In recent years, telomerase activity has been considered an important characteristic that differentiates between normal and cancerous cells. Because the authors often encountered difficulties in distinguishing between benign and malignant adrenal tumors, they investigated whether the expression of telomerase activity could distinguish potentially malignant adrenal tumors.

METHODS

The authors examined telomerase activity in 48 samples of adrenal tumor tissue and 27 samples of adjacent normal adrenal tissue. All samples were obtained from 48 patients who underwent surgery at Hamamatsu University Hospital in Hamamatsu, Japan. Based on the clinical and postoperative pathologic examinations, 45 samples were diagnosed as benign and 3 were diagnosed as malignant. Telomerase activity was examined using a telomerase repeat amplification protocol (TRAP) assay.

RESULTS

Of the 48 adrenal tumor samples, 7 (14.6%) had telomerase activity. All adjacent normal adrenal tissues were negative for telomerase activity. Of the telomerase positive samples, two were clinically known adrenocortical carcinoma, and another was metastatic adrenal tumor from lung carcinoma. Four other telomerase positive samples were diagnosed as benign after clinical and initial pathologic examinations. However, two of the patients from whom these samples were taken developed metastatic lesions after adrenalectomy.

CONCLUSIONS

A telomerase assay of adrenal tumors may help predict their malignant potential.

Recurrent aciclovir-resistant herpes simplex in a child with Wiskott-Aldrich syndrome

A boy with Wiskott-Aldrich syndrome suffered from thymidine kinase (TK)-altered and aciclovir-resistant herpes simplex virus type 1 (HSV-1) skin infections. He presented with severe herpes simplex around the left eye in March 1993 at the age of 8 years. HSV-1 strain TAS was isolated and was shown to be susceptible to aciclovir (50% inhibitory concentration (IC50) 0.23 microg/mL). He was treated with intravenous (i.v.) high dose aciclovir, 2 mg/kg per h, which produced an improvement. About 1 year later (May 1994), a severe herpes simplex infection appeared on his face, arm, genitalia, back and foot. Treatment with i.v. aciclovir, 2 mg/kg per h, was initiated, but the skin lesions did not improve. HSV-1 strain TAR was isolated and was shown to be resistant to aciclovir (IC50 36 microg/mL). HSV-1 TAR and TAS were susceptible to vidarabine (IC50 4. 4 and 2.9 microg/mL, respectively). The skin lesions were treated with i.v. vidarabine, 15-20 mg/kg per day, and healed satisfactorily. However, in March 1995, the patient again experienced a severe herpes simplex infection around the left eye. HSV-1 strain R95 was isolated and was shown to be resistant to aciclovir (IC50 36 microg/mL). Diminished sensitivity of HSV-1 TAR and R95 to aciclovir was associated with reduced viral TK activity and loss of aciclovir phosphorylation activity.

[Association of bone mineral density with vitamin D receptor gene polymorphism--changes in radial bone mineral density with long-term follow-up: longitudinal study]

Recent studies have shown that genetic effects on bone mineral density (BMD) and bone turnover are related to vitamin D receptor (VDR) gene polymorphism. However, discordant studies have been published and it is still not clear whether VDR genotypes influence bone mass accretion and/or postmenopausal bone loss. To assess allelic influence of the VDR gene on BMD, we determined changes in 1/6-radial-BMD by several repeat measurements in the same subjects for about ten years and analyzed VDR polymorphism of BsmI restriction enzyme in 53 normal healthy Japanese women (age: 50.3 +/- 4.7 years, mean +/- SD). Twenty-seven (age: 53.2 +/- 4.7 years) of the subjects were post-menopausal (POST group). Among these 53 subjects, the distribution of bb, Bb and BB genotypes was 64.2%, 34% and 1.9%, respectively. The genotype frequencies in this study were very similar to those in previous reports concerning other Japanese women. There was no difference between the b group (women with bb genotype) and B group (women with BB or Bb genotype) in age, body weight, height, body mass index (BMI), years since menopause, serum osteocalcin and serum alkaline phosphatase values. In the POST group, BMD of the B group at menopause was lower than that of the b group (p < 0.05). About ten years after menopause, BMD did not differ significantly between these groups because the decrease in BMD in the b group was larger than that in the B group. Regarding changes in BMD in the POST group for four years after menopause, BMD of the b group was significantly decreased compared with the B group (p < 0.01). Our findings suggest that the differences in BMD by VDR genotype were larger among pre- and pri-menopausal women and seemed to decrease with years after menopause. It is suggested that there are other factors influencing BMD and postmenopausal bone loss in elderly women.

Denture mobility with six degrees of freedom during function

The purpose of this study was (1) to assemble and verify a system to measure the three-dimensional (3-D) movement of the upper and lower complete dentures and the movement of the mandible simultaneously, and (2) to analyse the relation between denture movements and the path of closure of the mandible during function. A 3-D motion capture system with four infrared TV cameras was used for this purpose. The relation between the dentures and the mandibular movements was analysed through the change of the inner product of normal vectors of the denture occlusal planes and mandibular planes. The mandibular movements were classified into two types; the normal stroke (the path of closure was on the ipsilateral side of mastication) and the reverse stroke (on the contralateral side). The results showed that the system could measure the denture mobility within a 0.3 mm error. The mobility of the upper dentures had a correlation to the path of closure of the mandible regardless of the working side or nonworking side, and the lower dentures had a tendency to move toward the working side.

[The effects of YM26818: 1-(2-dimethylaminoethyl)-1-(3,4,5-trimethoxyphenyl)urea and derivatives on pulmonary surfactant secretion and lung compliance]

To discover a novel compound which has an effect on pulmonary surfactant (PS) secretion, we studied the effects of various compounds on PS secretion by measuring the contents of PS in the bronchoalveolar lavage (BAL) fluid in guinea pigs. In the chemical modification study of ambroxol, which is known as a PS secretagogue, and a compound we discovered from our compounds library, 1-(2-dimethylaminoethyl)-1-(3,4,5-trimethoxyphenyl)urea: YM-26818 (the increasing effect on PS in BALF, 34.7% at 50 mg/kg, i.p.). In the surfactant deficient model induced by BAL in guinea pigs, YM-26818 (5 and 10 mg/kg, p.o.) significantly increased the contents of PS in the BAL fluid compared with that of control animals (5 mg/kg: 60.3 +/- 8.0, 10 mg/kg: 59.4 +/- 4.3% increase). Concomitantly by these effects, the recovery of lung compliance was observed in this model (AUC of lung volume, control: 560 +/- 15, YM-26818 5 mg/kg: 898 +/- 51, YM-2681 10 mg/kg: 956 +/- 11 ml.min). These results may indicate that YM-26818 is useful for the therapy of adult respiratory distress syndrome (ARDS) and obstructive pulmonary diseases.