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Biomedical subjects

T Ono

Publications and source records attributed to T Ono.

At least 883 records · Page 49Linked to original sources
PubMed1990

Novel 1,4-dihydropyridine calcium antagonists. I. Synthesis and hypotensive activity of 4-(substituted pyridyl)-1,4-dihydropyridine derivatives.

A series of 4-(substituted pyridyl)-1,4-dihydropyridine derivatives were synthesized and their hypotensive effects examined. Several compounds, 2-(N-benzyl-N-methylamino)ethyl methyl 1,4-dihydro-2,6-dimethyl-4-(3-nitro-2-pyridyl)-3,5-pyridinedicarboxylate (2b), its 4-(4-nitro-2-pyridyl) analogue (2g), 4-(3-trifluoromethyl-2-pyridyl) analogue (2c), 4-(2-trifluoromethyl-3-pyridyl) analogue (3e), 4-(4-cyano-2-pyridyl) analogue (2e), 4-(2-cyano-3-pyridyl) analogue (3d), and 4-(6-bromo-2-pyridyl) analogue (2i), were found to have a hypotensive activity parallel to that of nicardipine; 2c and 3e, in particular, had approximately twice the duration of nicardipine, and 2e had the most potent hypotensive activity of all the derivatives synthesized.

Animals↗
PubMed1990

[Inhibition of cytochrome P-450-dependent monoxygenase activities by a synthetic androgen danazol in mouse hepatic microsomes].

The inhibitory effect of danazol, a synthetic androgen, on the hydroxylations of testosterone as a model for endogenous steroids and the dealkylations of aminopyrine and 7-ethoxycoumarin as models for xenobiotics in mouse hepatic microsomes in vitro was studied. Danazol inhibited these enzyme activities in a dose-dependent fashion. The inhibition constants (Ki) of danazol for these enzyme activities were 1-4 orders of magnitude lower than those of cimetidine, while there was a great difference among the inhibitory potencies of danazol for each enzyme activity. Addition of danazol to microsomal preparation resulted in a reverse type I difference spectrum and the spectrophotometric analysis revealed that danazol had a high affinity for cytochrome P-450 with dissociation constants (Ks) of 0.9 and 4.2 microM, which were 2 orders of magnitude lower than those of cimetidine. On the other hand, danazol did not significantly affect reduced nicotinamide adenine dinucleotide phosphate cytochrome c reductase activity and levels of cytochrome P-450 in the microsomes. These results suggest that danazol is a highly potent inhibitor for several cytochrome P-450-mediated metabolisms of testosterone and xenobiotics in mouse hepatic microsomes.

Animals↗
PubMed1990

[Diagnosis of abortion and fetal death by the ultrasonographical device in cynomolgus monkeys under indoor individually-caged conditions].

This paper describes the rate of naturally occurring abortion and fetal death that were diagnosed by the use of an ultrasonographical device in 683 pregnant cynomolgus monkeys (Macaca fascicularis) of which 542 were wild-imported monkeys and 141 were colony-bred monkeys. All of these animals had become pregnant by the 3-day timed mating system. The combined rate of abortion and fetal death was 7.0% in the wild-imported animals and 7.8% in the colony-bred animals. There were no significant differences in the rate with respect to different ages and to different period of feeding at Tsukuba Primate Center. Seventy-eight per cent (38 monkeys) of the total cases occurred during the first 5 to 9 pregnancy-weeks.

Abortion, Veterinary↗
PubMed1990

[Respiratory neurons in medullary reticular formation which directly project to hypoglossal motoneurons in cats].

The present study was carried out to determine the location of the excitatory premotor neurons projecting to the hypoglossal motoneurons (XII MNs) that show respiratory activities in pentobarbital-anesthetized cats. Projections from these hypoglossal premotor neurons to the phrenic motoneurons were also investigated. The following results were obtained. (1) Injection of a fluorescent dye (Fast Blue, FB) into the hypoglossal nucleus and another fluorescent dye (Nuclear Yellow, NY) into the phrenic nucleus the cells in the medullary reticular formation labelled retrogradely with FB and/or NY mainly in the region ventrolateral to the nucleus of the tractus soritarius (vl-NTS) and dorsomedial to the nucleus ambiguus (dm-AMB). (2) There were respiratory neurons in the region vl-NTS and dm-AMB which antidromically responded to the stimulation of the hypoglossal nucleus. Some of them antidromically responded also to the stimulation of the phrenic nucleus. (3) Averaging of the hypoglossal and phrenic nerve discharges by spontaneous spikes of single respiratory neurons in the region vl-NTS and dm-AMB revealed a facilitation in the hypoglossal nerve discharge. In some of these excitatory hypoglossal premotor neurons, a facilitation was also revealed in the phrenic nerve discharge. It was concluded that there were respiratory neurons in the region vl-NTS and dm-AMB which were excitatory premotor neurons projecting to the XII MNs showing respiratory activities. Some of them had excitatory projections to both the hypoglossal and phrenic motoneurons via the bifurcating axons.

Action Potentials↗
PubMed1990

Chemical modification of erythromycins. III. In vitro and in vivo antibacterial activities of new semisynthetic 6-O-methylerythromycins A, TE-031 (clarithromycin) and TE-032.

The in vitro and in vivo antibacterial activities of 6-O-methylerythromycin A (TE-031, A-56268, or clarithromycin) and 6,11-di-O-methylerythromycin A (TE-032) have been compared with those of erythromycin A (EM) and josamycin (JM). TE-031 and TE-032, having the same antibacterial spectra as EM, are active against aerobic Gram-positive bacteria, some Gram-negative bacteria, anaerobic bacteria, L-form bacteria and Mycoplasma pneumoniae. The activity of TE-031 against clinical isolates is equal to or two times more potent than that of EM, whereas TE-032 is slightly less active than EM. The activities of TE-031 and TE-032 are pH dependent (more active at pH 8 than at 5) and are increased by adding serum to medium. TE-031 and TE-032 show dose-related bactericidal activities against Haemophilus influenzae. The therapeutic efficacies of TE-031 and TE-032 against systemic and subcutaneous infections provoked by Gram-positive bacteria in mice are 4- to 35-fold superior to those of EM and JM. TE-031 and TE-032 have demonstrated higher and longer-lasting plasma levels than EM when administered orally to mice, rats or dogs.

Animals↗
PubMed1990

[Preliminary screening for antiviral AIDS drugs. I. Report on fiscal year 1988].

Preliminary screening for antiviral AIDS drugs has been carried out, using three different in vitro assay systems. Among 105 samples tested, 13 were found to inhibit the growth of HIV in vitro. Eleven of 13 were well-known anti-HIV chemicals, while the remaining two of plant origin were new chemicals whose anti-HIV activities have not been reported elsewhere.

Antiviral Agents↗
PubMed1990

Effect of ketotifen on the reactivity of eosinophils with the incubation of anti-IgG.

Blood eosinophils obtained from 25 patients with bronchial asthma were reacted with anti-IgG or with normal rabbit serum as the control. Morphological changes were examined by light microscopy, scanning electron microscopy and transmission electron microscopy. Reactive eosinophils in morphology with anti-IgG (27.8 per cent) were significantly higher (p less than 0.001) than those with the control (1.2 per cent). We also examined the effects of ketotifen and tranilast, both of which have eosinophil chemotactic inhibitory functions, on the morphological changes. Ketotifen altered the morphological reactivation of eosinophils and the generation of leukotrienes induced by anti-IgG, and this inhibition occurred in a concentration-dependent manner. Tranilast had no effect on the morphology of eosinophils and the generation of leukotrienes. These results suggest that eosinophil IgG receptors may have a role in the pathogenesis of asthma and that ketotifen may prevent their reactivity and, thus, could be of potential use in the treatment of asthma.

Adolescent↗
PubMed1990

Clinical application of electric resistance welding and soldering methods to removable partial dentures.

The joining procedure for uniting metal structures is very important in the construction of removable partial dentures. However, it has several restricted problems in joining wrought wire clasps to rests or major connectors. For example, the base metal wires made of chromium-cobalt alloy are subject to changes in their mechanical properties caused by heating, and damage to acrylic resin materials (denture base and artificial teeth) occurs in the repair of removable partial dentures by using the torch soldering method. In this paper, in order to resolve these problems, an electric resistance welding machine was applied to attach wrought wire components to a removable partial denture framework. This welding machine was used to attach metal structures temporarily to each other, and to solder the welded joint with hard solder. Consequently, some problems of the conventional torch soldering method were improved by using the electric resistance welding and soldering methods. It was suggested that the clinical application of the electric welding and soldering methods was very useful in the construction of removable partial dentures.

Aged↗
PubMed1990

[Removable partial dentures applied by electric welding and soldering methods].

The joining procedure for uniting metal structures is very important in the dental clinic, and various kinds of metal joining methods have been performed for clinical application. The conventional torch soldering method using a blow torch has been generally adopted. However, it has several clinical problems, especially in the construction of removable partial dentures. The base metal wires made of a chromium-cobalt alloy are subject to changes in their mechanical properties caused by heating, when wrought wire clasps are joined to rests or frameworks. In addition to the flexibility of wrought wire clasps, damage to acrylic resin denture bases and acrylic resin teeth occurs in the repair of removable partial dentures. In this paper, the electric resistance welding and soldering methods were applied to attach wrought wire components to a removable partial denture framework to resolve the problems of the torch soldering method. As a result, it is suggested that these electric resistance welding and soldering methods have the following advantages, as compared with the conventional torch soldering method. 1. When using this electric resistance welding method, it is possible to fix metals temporarily to each other more securely and strongly than the conventional temporary fixation methods using sticky wax or acrylic resin. 2. The electric resistance soldering method does not require any heat insulation or a partition as the torch soldering method does, because the soldered area is only heated partially. 3. In the case of soldering electrically wrought wire clasps to metal structures such as rests and connectors, there is no fear of of overheating a wide area of wires.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromium Alloys↗
PubMed1990

[Expression of HLA-class I and II antigens on basal cell carcinoma].

Sixteen cases of Basal Cell Carcinoma have been tested with monoclonal antibodies to HLA-class I, beta 2-microglobulin, HLA-DR, DP and DQ antigens immunohistochemically using frozen tissues. HLA-class I antigens were expressed weakly on BCC in thirteen and fifteen out of sixteen cases using two different monoclonal antibodies respectively. beta 2-microglobulin was expressed differently with the same intensity as normal epidermis in 6 cases, weaker than normal epidermis in 8 cases and absent in 2 cases. There is no correlation with the expression of HLA-class I between histological type and lymphocyte infiltration. On the other hand, HLA-DR, DP and DQ antigens were positive in 4, 3 and 3 cases respectively. But the percentage of positive cells for HLA-class II were only 1-2%. The expression of HLA-DR antigen was most strongest among HLA-class II antigens.

Aged↗
PubMed1990

[Frequency of food intake of dentulous and complete denture wearers].

The study was carried out on 1466 subjects, whose ages ranged from 20 to 80 years of age, of whom 1181 were dentulous and 285 were complete dentures. We studied the frequency with which the 1466 cases partook of food. The results were as follows: 1) Ingested foods were classified into 10 groups along with the frequency with which they were ingested on a yearly seasonal basis. Food groups were classified as follows: vegetables, grain, sea food, beans, meat, seaweed, potatoes, fruits, etc. 2) The Ingested foods of the dentulous group were similar to those of the complete denture wearers. 3) In all age groups the foods most ingested were: steamed rice, wakame, tofu, bread, scallions, Japanese omelette, and tomatoes. 4) The younger subjects (20 to 39 years) statistically ate significantly lower amounts of steamed rice than did the older age groups. 5) The younger generation ate more meat, while the older groups ate more sea food.

Adolescent↗
PubMed1990

[Enhanced effect of hepatic arterial infusion of anticancer drugs of rabbit VX-2 hepatic implants].

To obtain a high concentration of adriamycin (ADR) in hepatic malignant tumors, intraarterial injection method was devised depending upon the different application with Lipiodol. The VX-2 carcinoma was implanted in the domestic rabbit after laparotomy. When the tumor grew to 2 cm in size, ADR was infused through the hepatic artery by the following four methods; Group 1, one shot injection of ADR (n = 5); Group 2, ADR infusion between Lipiodol injections (n = 6); Group 3, infusion of Lipiodol suspended with Urographin dissolved in Lipiodol (n = 7); Group 4, ADR dissolved in Lipiodol by Sonicator (n = 5). ADR concentration of the tumor, liver, heart, kidney and bone marrow were measured by HPLC one hour after ADR administration. In Group 3, the concentrations of ADR within tumor were significantly higher than in the other three groups (p less than 0.01 or less than 0.02). In addition, the tumor-to-liver ratio of ADR was significantly higher in the other three groups (p less than 0.05 or less than 0.10). ADR concentration of heart and kidney was lower in Group 3 than in the other groups. These results suggest that Lipiodol may enhance the therapeutic effects of hepatic arterial ADR infusion by hepatic arterial ADR infusion by increasing its tumor uptake.

Animals↗
PubMed1990

[A case of asbestos exposure complicated by a malignant pheochromocytoma].

Reported is a case of non-functioning malignant pheochromocytoma. The patient had an occupational history of asbestos exposure and pleural plaque was seen in the chest X-rays. The tumor appeared from right adrenal gland and its size was 12 x 15 cm, which was measured by CT scanning. This determined to be non functioning because catecholamines in the serum and VMA in the urine were within normal limits. A metastasis of this tumor was seen in the lung, the liver, and the bone. So far as is known, this is the first case of asbestos exposure complicated with malignant pheochromocytoma that has been reported in the Japanese literature.

Adrenal Gland Neoplasms↗
PubMed1990

[Systemic mast cell disease associated with cutaneous xanthomas and markedly elevated serum IgE].

Systemic mast cell disease (SMCD) is a rare disease often associated with symptoms of general malaise, pruritus, diarrhea, vomiting, fever, urticaria pigmentosa, hepatosplenomegaly and lymphadenopathy. We reported a case of SMCD associated with cutaneous xanthoma and serum hyper IgE. Skin biopsy revealed xanthomas and diffuse infiltration of mast cells in the dermis. The association of SMCD with xanthoma was reported in the literature for only one case. The hyper IgE could be due to the defect of IgE receptors on the cell membrane of mast cells of dysfunction of T and/or B cell. Any of the treatment using H1 and H2 receptor blockade, disodium cromoglycate, adrenocorticosteroid or chemotherapy (VEPA) were not effective. The patient died of pulmonary edema and multiple organ failure 7 months after the diagnosis was established. The crush method for the cytological examination of bone marrow was considered more useful than smear method for the diagnosis of SMCD.

Humans↗