[Generation of the 5' EST using 5'-end enriched cDNA library].
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to S Sugano.
Explore the source record for details and available documents.
We studied power spectral analysis of heart rate (HR) variability in the horse, with the hypothesis that the quantitative information provided by the spectral analysis of HR variability reflects the interaction between sympathetic and parasympathetic regulatory activities. For this purpose, electrocardiogram, blood pressure (BP) and respiratory (Resp) waveform were simultaneously recorded from Thoroughbred horses (3-5 years old) and analyzed by power spectrum. There were two major spectral components at low-frequency (LF) and high-frequency (HF) bands for HR variability. The peak of Resp variability clearly occurred at the HF range. In contrast to Resp variability, the power spectra of BP variability occurred at lower frequencies. The maximum coherence between HR and Resp variabilities and HR and BP variabilities occurred at approximately 0.15 and approximately 0.03 Hz, respectively. These relationships were similar to the ensemble spectra. On the basis of these data, we have defined two frequency bands of interest: LF (0.01-0.07 Hz) and HF (0.07-0.6 Hz). Therefore, we believe that power spectral analysis of HR variability provides a very powerful technique for assessing autonomic nervous activity in the horse.
The promoter of TGF-beta type II receptor lacks TATA box or CAAT box. In order to define the exact transcriptional start site(s), we used "oligo-capping" method developed by ourselves. The major transcripts were started from GAA located between -35 and -33 relative to 5' end of cDNA. Other minor transcripts started from -4, +11 and +17. Deletion analysis of this promoter region revealed that it contained two adjacently located promoters (P1 and P2) capable of acting by itself. The P1 is located between -22 and +55 which covers the minor transcriptional start sites described above. The P2 is located just upstream of the P1 between -137 and -22. The results showed all of the transcripts were started either from P1 or P2.
The biosynthesis of the alternative oxidase protein consisting of cyanide-insensitive and salicylhydroxamic acid-sensitive respiration in Aspergillus niger was investigated. Cyanide-insensitive respiration was enhanced by addition of antimycin A to the incubation mixture, but repressed by the addition of cycloheximide, emetine, puromycin (cytosolic translation inhibitors), carbonylcyanide-m-chlorophenylhydrazone (uncoupler) and actinomycin D (transcription inhibitor). These results show that the alternative oxidase protein of A. niger was synthesized de novo in cytosol and transported in mitochondria.
From proteolytic digest of swine hemoglobin, we isolated four peptide, E-1 (Phe-Gln-Lys-Val-Val-Ala), E-2 (Phe-Gln-Lys-Val-Val-Ala-Gly), peptide 30-3 (Phe-Gln-Lys-Val-Val-Ala-Lys) and H-1 (Gly-Lys-Lys-Val-Leu-Gln). These peptides inhibited angiotensin I-converting enzyme activity with an IC50 of 5.8, 7.4, 2.1 and 1.9 microM, respectively. Oral administration of 50 mg/kg E-1 and 50 mg/kg H-1 decreased blood pressure in spontaneously hypertensive rats. In normotensive rats, oral administration of 500 mg/kg E-1 and 500 mg/kg H-1 inhibited the pressor effect of i.v. administrated 300 ng/kg angiotensin I, possibly by inhibiting its conversion to angiotensin II. These results suggest that these peptides are orally effective inhibitors of angiotensin I-converting enzyme that have a hypotensive effect.
This study shows the effects of a selective endothelin ET(B) receptor agonist, IRL 1720 {Ac-[Ala11,15]endothelin-1-(8-21)}, on cardiovascular responses in anesthetized spontaneously hypertensive rats and Wistar-Kyoto rats. Single intravenous bolus injection of IRL 1720 caused a dose-related short-lasting fall in blood pressure, left ventricular pressure and myocardial contractility. However, repeated intravenous bolus injection of 10(-5) mol/kg IRL 1720 produced a biphasic response consisting of an initial short-lasting decrease followed by a sustained increase in these parameters. The initial decrease was reduced, whereas the following increase was enhanced with the repeated injections of IRL 1720. The cardiovascular pressor response was not inhibited by the endothelin ET(A) receptor antagonist, FR139317 ((R)2-[(R)-2-[(S)-2-[[1-(hexahydro-1H-azepinyl)]carbonyl] amino-4-+methylpentanoyl] amino-3-[3-(1-methyl-1H-indolyl)]propionyl]amino -3- (2-pyridyl)propionic acid). The effects of IRL 1720 were qualitatively similar but more potent in spontaneously hypertensive rats than in Wistar-Kyoto rats. These results suggest the existence of two types of endothelin ET(B) receptor for IRL 1720: a tachyphylactic endothelin ET(B) receptor that mediates cardiovascular depressor responses and a less tachyphylactic endothelin ET(B) receptor that mediates pressor responses in the rat.
The aim of this study was to demonstrate the presence of nasal 'cold' receptors, through recordings of action potentials from the ethmoidal nerve (EN), in guinea pigs and to characterize their responsiveness to l-menthol and capsaicin. Constant flows (400 ml/min) of room air (20 degrees C), warm air (45 degrees C), room air containing l-menthol, and cold air (-5 degrees C) were directed into the nasal cavity in the inspiratory direction via a nasopharyngeal catheter in the anesthetized guinea pigs breathing spontaneously through a tracheostomy. The ethmoidal afferent activity was increased by cold air, and to a greater extent by l-menthol but hardly by warm air. After topical anesthesia of the nasal cavity with 2% lidocaine, cold air and l-menthol no longer stimulated the EN. L-menthol noticeably stimulated the EN even after repeated capsaicin instillation into the nose, but these values were lower than those following the l-menthol stimulus before the 1st capsaicin treatment. These results suggest that the ethmoidal nerve in guinea pigs has cold-sensitive receptors which consist of both small myelinated fibers and C-fiber endings.
The insertion of a copper (II) ion into mesoporphyrin by a monoclonal catalytic antibody has been investigated kinetically by measuring the increase in Soret absorbance due to the production of copper (II)-mesoporphyrin. The initial rate of the reaction showed saturation kinetics as a function of the mesoporphyrin concentration, while it increased linearly with an increase in the copper (II) concentration. Based on observations, a scheme for the reaction was proposed: mesoporphyrin binds to the antibody to form a complex, and copper (II) binds to the complex to yield copper (II)-mesoporphyrin. Kinetic parameters for the respective steps were estimated, and the thermodynamic parameters were calculated. The binding of mesoporphyrin to the antibody was endothermic and entropically driven. This implies that hydrophobic interactions are an important factor in the binding. Free energy profiles for the antibody-catalyzed and uncatalyzed reactions were drawn by use of the obtained thermodynamic parameter values. The results demonstrate that the rate acceleration by, the antibody is ascribable to transition-state stabilization, and suggest that the structure of mesoporphyrin in the complex is more distorted than that of free mesoporphyrin.
Dihydroxycholesterol and pregnenolone were clearly detected on HPLC when 22R-hydroxycholesterol was incubated with a reconstituted P450scc system containing equimolar amounts of P450scc and adrenodoxin. The dihydroxycholesterol, which has been accepted to be an intermediate in the conversion of 22R-hydroxycholesterol to pregnenolone, accumulated when adrenodoxin was at a subsaturating level with respect to P450scc. The formation of the intermediate increased with increasing pH in the range of 7.2 to 8.1, and the ratio of the intermediate to the product, pregnenolone, increased with increasing pH. When the binding of P450scc to adrenodoxin was weakened by elevation of the ionic strength, the formation of the intermediate relative to the product increased. The apparent Km for dihydroxycholesterol at a subsaturating level of adrenodoxin was about 7 microM, in contrast to 4 microM at a saturating level of adrenodoxin, implying that the affinity of dihydroxycholesterol is lower at a subsaturating level of adrenodoxin than at a saturating one. These results suggest that a subsaturating level of adrenodoxin weakened the binding of dihydroxycholesterol to P450scc and thus the intermediate, dihydroxycholesterol, was released. An intermediate other than dihydroxycholesterol, obtained when cholesterol was used as the substrate, was identified as 22R-hydroxycholesterol by HPLC and mass spectroscopic analysis. The intermediate obtained when 22R-hydroxycholesterol was used as the substrate was identified as 20R,22R-dihydroxycholesterol by HPLC, mass, and 1H-NMR spectroscopic analyses. These results provide direct evidence that cholesterol is metabolized to pregnenolone by way of 22R-hydroxycholesterol and 20R,22R-dihydroxycholesterol by P45 scc.
We have studied the autonomic nervous function in voles (Microtus arvalis) and mice. For this purpose, ECGs were recorded from conscious and unrestrained voles and mice using radiotelemetry and the autonomic nervous function was investigated by the power spectral analysis of heart rate variability. Heart rate in voles was lower than mice and the coefficient of variance was larger in voles. In the power spectra of voles and mice, there were two major spectral components with the high frequency (HF) peak generally appearing between 2.0 and 4.0 Hz, and the low frequency (LF) peak appearing below 0.6 Hz. On the basis of this data, we set the two frequency bands as LF (0.1-1.0 Hz) and HF (1.0-5.0 Hz) to evaluate autonomic nervous function. The LF and HF powers were larger in voles than mice. The LF/HF ratio was thought to provide a convenient index of autonomic nervous balance and was smaller in voles than mice. The LF powers in both species were reduced by atropine, but propranolol reduced the LF power only in mice. The HF power was reduced by atropine only in voles. The intrinsic heart rate produced by a double blockade with atropine and propranolol in voles was almost the same as control levels, but in mice was lower than controls. The ratio of the LF and HF powers by a double blockade were almost the same as those of the administration of atropine in voles, but nearer to propranolol in mice. These results suggested that the parasympathetic nervous function was predominant in voles, but the sympathetic one was predominant in mice.
We have studied the physiological and behavioural responses in small rodents to ambient alterations. For this purpose, voles and mice were exposed to relatively low (12 degrees C) and high (35 degrees C) ambient temperatures, and heart rate (HR), locomotor activity (LA) and body temperature (BT) were recorded using telemetry system. The control HR (at 24 degrees C) of voles was lower than that of mice. The 'heat exposure' decreased HR to 85.0 +/- 3.3% in voles, and to 78.0 +/- 3.2% in mice compared with the mean HR of the same time in the control day. The 'cold exposure' increased the HR to 131.9 +/- 8.8% in voles, and 119 +/- 10.9% in mice. The decreasing rate of HR in heat exposure was smaller in voles than mice, and in cold exposure the increased rate was larger in voles than mice. Cold exposure decreased BT in both species; 96.1 +/- 0.5% in voles and 93.7 +/- 1.0% in mice. The LA was not changed significantly by heat exposure in either species, but was partially increased by cold exposure. These results demonstrate that telemetry was helpful for qualitative and quantitative behavioural studies in small rodents, and confirmed that the physiological and behavioural responses to ambient temperature changes differed between these animals.
Cardiorespiratory effects of capsaicin (CAPS) solution instilled into the larynx and the reflex mechanisms were investigated in rats with spontaneous breathing or under artificial ventilation. The first challenge with CAPS (100 micrograms/ml, 20 microliters) markedly inhibited spontaneous breathing due to a considerable prolongation of expiration time (TE) (1785% of control) in all rats. Circulatory changes such as hypertension (mean systolic blood pressure-210 mmHg) and bradycardia (10.5% decrease in heart rate) were also elicited by the 1st challenge with CAPS. These changes were largely reduced by the second challenge of CAPS; but not abolished in 3 of 5 rats by bilateral section of the superior laryngeal nerves (SLNs) and recurrent laryngeal nerves (RLNs). The bradycardia and hypertension after the CAPS-instillation were able to be elicited to the same extent in rats in the absence of apnea under artificial ventilation. The bradycardia was entirely abolished by pretreatment with atropine injection, while the hypertension was largely inhibited by phentolamine and propranolol. These results demonstrated that the laryngeal and/or pharyngeal noxious stimulus could induce marked cardiorespiratory reflexes, where the circulatory changes could be elicited in the absence of apnea, suggesting the presence of eliciting mechanisms of circulatory changes independent on the occurrence of apnea. In addition, it was also suggested that those cardiorespiratory responses were mediated by the afferents such as unmyelinated C-fiber endings and thin myelinated fibers and by the efferents, both the parasympathetic and sympathetic nervous systems.
Auditory brainstem response (ABR) is a useful method in evaluating auditory function in human. To investigate the ABR threshold is more effective than to pursue the trends in each component of ABR. In this study, tone burst sound stimuli were employed and the ABR threshold shift caused by kanamycin administration was investigated in dogs. In a series of monitoring of ABR against short-period auditory lesions, changes in the ABR waveform after intravenous administration of kanamycin were detected. These changes returned gradually and were reversible. The changes in ABR against long-period auditory function disorder were perceived by an increase in the ABR threshold. The ABR threshold shift occurred earlier in the high frequency sounds than in the lower frequency sounds. This is why amino glycoside antibiotics damage the cochlear hair cells in the basal layer and lead to the loss of hearing selectively for high frequency tones. These findings suggest that tracing of the ABR threshold by tone bursts could provide information that has a specificity for frequency in hearing tests and is a useful method in clinical veterinary medicine or/and toxicological tests.
BACKGROUND: There is no useful oscillometric device to measure the systemic arterial pressure in small experimental animals except rats. Therefore we evaluated a recently developed automatic oscillometric device for the indirect blood pressure measurement in guinea pigs.METHODS: Twenty male Hartley guinea pigs were used. We found that unanaesthetized guinea pigs stayed comfortably in a guinea pig-holder without training. A pneumatic cuff was placed snugly around the crus of the left limb. Cuff size was selected according to previous recommendations (cuff width = limb circumference x 0.4). Systolic blood pressure corresponded to the point at which oscillations began to increase; mean arterial pressure corresponded to the point at which the oscillations peaked. Diastolic blood pressure was calculated from the values of systolic and mean blood pressures. To test the accuracy of this device, the direct and indirect values were arbitrarily collected from simultaneous recordings of six anaesthetized guinea pigs with various levels of blood pressure induced by intravenous noradrenaline infusions. RESULTS: The oscillometric device for indirect blood pressure measurements allows the measurement of blood pressure easily and quickly. Twenty unanaesthetized guinea pigs had a heart rate of 280.0 +/- 6.7 beats/min (mean +/- SEM) and systolic, mean and diastolic blood pressures of 94.0 +/- 2.2, 63.6 +/- 1.7 and 48.4 +/- 1.6 mmHg, respectively. These values are almost the same as those found in earlier studies. Correlation coefficients between direct and indirect values were > 0.9 for all blood pressures. CONCLUSIONS: These results suggest that this device may be valuable for monitoring systemic arterial blood pressure in guinea pigs.
Explore the source record for details and available documents.
The protein C anticoagulant pathway is an important downregulating mechanism of the blood coagulation cascade. We report a 47-yr-old male with Budd-Chiari syndrome and occlusion of the inferior vena cava. His plasma protein C antigen level was decreased to 42%, and its activity was 34%. Other coagulable factors were normal. Protein C deficiency should be considered a possible etiological factor of the Budd-Chiari syndrome.
Epstein-Barr virus DNA was detected in 3 cases of lymph node metastasis with nasopharyngeal carcinoma, using in situ hybridization. EBV-DNA was demonstrated on the nuclei of the neoplastic cells, and was absent on those of lymphocytes. Localization of EBV-DNA in neoplastic cells was confirmed by the double-labeling method combining in situ hybridization and immunocytochemistry. Direct evidence of the presence of EBV-DNA in malignant epithelial cells from lymph node metastasis with nasopharyngeal carcinoma was clearly demonstrated in this study.
A multicenter study was carried out in 24 institutions in Kanagawa Prefecture, Japan. The subjects were 113 male and 145 female patients, ranging in age from 28 to 86 years (mean 63.7) who complained of dryness of the mouth and throat. The following illnesses were diagnosed: xerostomia and pharyngoxerosis in 161, radiation xerostomia and pharyngoxerosis in 56, chronic pharyngitis with dry mouth and throat in 22, and Sjögren's syndrome in 7. Eleven patients had other symptoms. The subjects were given a 3-g pack of granules of formula ophiopogoins three times a day before a meal. Their subjective symptoms and objective signs were examined prior to, 2, and 4 weeks after the beginning of therapy.