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Biomedical subjects

T Someya

Publications and source records attributed to T Someya.

At least 109 records · Page 6Linked to original sources
PubMed1990

Measurement of haloperidol reductase activity in red blood cells and reduced haloperidol/haloperidol ratios in plasma in oriental psychiatric patients.

1. The authors established a method for measuring haloperidol (HAL) reductase activity in human red blood cells. 2. Characteristics of the HAL reductase in red blood cells were examined. This enzyme reaction was NADPH dependent, and the optimum pH was at 8.2-8.9. Vmax and Km were calculated as 25-150 pmol/hr/10(6) RBC and 160-2600 microM respectively. 3. HAL reductase activities in red blood cells from 14 patients treated with HAL were in a range of 9.7-20.8 pmol/hr/10(6) RBC. So far we did not find any significant correlation between HAL reductase activities and reduced HAL/HAL ratios in plasma.

Adult↗
PubMed1990

Antiproliferative effect of hyperthermia and ACNU on cultured human malignant melanoma cells.

Human malignant melanoma cultured cells were treated either with ACNU (1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chlorethyl)-3-nitro sourea hydrochloride), hyperthermia, or the combination of ACNU and hyperthermia. The combination treatment inhibited the cell growth to a slightly synergistic degree compared to the respective single treatments. The present in vitro experimental results support in part the finding of our previous report that the combination treatment with ACNU and hyperthermia have a significantly synergistic antitumor effect to human melanoma transplanted to nude mice. However, the synergistic effect was much less intense in the present in vitro experiment. The difference may have resulted from the environmental differences between in vitro and in vivo experimental systems.

Cell Count↗
PubMed1990

Nerve sheath myxoma. An immunohistochemical study of a case.

An 18-year-old Japanese male presented with a normal-skin-colored, dome-shaped, slightly tender tumor on his left palm. Histopathologically, the tumor consisted of distinct lobules, which were separated by fibrous connective tissue. Each lobule was composed of spindle or round cells within a myxoid matrix, pathognomonic of nerve sheath myxoma. The mucinous material was positively stained by Alcian blue (pH 2.5) and toluidine blue (pH 4.0). Immunohistochemically, the majority of spindle cells were positive for S-100 protein (beta-subunit) and neuron-specific enolase. Our findings lend further support to the hypothesis that nerve sheath myxoma is derived from Schwann cells.

Adolescent↗
PubMed1989

Two types of Ca channels in smooth muscle cells isolated from guinea-pig taenia coli.

1) Two types of voltage dependent Ca channels with different conductances and inactivation kinetics were identified from cell-attached patch clamp recordings. One type, with a larger conductance of 25pS, had a threshold of activation near -40mV and the mean current inactivated slowly. A second type of Ca channel, with a smaller conductance of 12pS channel, but the averaged mean current inactivated rapidly. 2) Cadmium ions inhibited the large conductance Ca channel currents, while the small conductance Ca channel currents was not blocked. 3) Large conductance Ca channel current selectively inhibited by dihydropyridine derivative, Nifedipine. Small conductance Ca channel current is abolished in dose dependent manner by pyrethroid insecticide, tetranethrine.

Animals↗
PubMed1989

Multiple types of voltage-dependent Ca channels in mammalian intestinal smooth muscle cells.

(1) Whole-cell and single channel recording techniques have been applied to smooth muscle cells isolated from guinea-pig taenia coli to examine whether multiple types of Ca channels exist. (2) Whole-cell recordings under physiological Ca concentration (1.8 mM) revealed two current components with fast and slow inactivating kinetics. The fast inactivating component was present when cells were held at very negative potentials (-80 mV). It was insensitive to the dihydropyridine (DHP) derivative, nifedipine. In contrast, the slow inactivating component was present at less negative holding potentials. It was blocked by nifedipine. (3) The two current components were found to have closely similar voltage dependencies for activation. (4) These results suggest that the fast inactivating decay of the Ca current was mediated not only by the entry of Ca into the cell but also by a voltage-dependent process via a different type of Ca channel with fast inactivating kinetics. (5) Recordings from cell-attached membrane patches with 100 mM external Ba clearly showed the existence of multiple types of Ca channels with different conductances. (6) The large conductance channels (30 pS) activated at more positive potentials (0 mV) and their averaged current decayed much more slowly. The DHP Ca antagonist, nifedipine, inhibited the large conductance channels increasing the proportion of blank sweeps and reducing the averaged current. On the other hand, the DHP Ca-agonist, BayK 8644, increased the average current by increasing the mean open-times of the large conductance channels. The presence of micromolar Cd in the patch pipettes produced a flickering block of the large conductance channels.(ABSTRACT TRUNCATED AT 250 WORDS)

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1989

Haloperidol reduction can be assayed in human red blood cells.

One metabolite of haloperidol present in plasma is "reduced haloperidol." This study demonstrates that human red blood cells are capable of converting haloperidol to reduced haloperidol in vitro. The reductase involved requires NADPH, as does haloperidol (ketone) reductase in human liver cytosol.

Adult↗
PubMed1989

Dynamic aspects of airborne bacterial flora over an experimental area in a suburb and distribution of resistant strains to antibacterial agents among airborne staphylococci.

Airborne bacterial floras were investigated at stations A to E and P on the UOEH campus located in a suburb of the city of Kitakyushu. Bacterial collections were carried out by a filtration method using a soluble gelatin foam filter at an altitude of 1 m from the ground and viable bacterial cells were enumerated on nutrient agar plates supplemented with 50 micrograms/ml cycloheximide. At station P, where airborne bacterial composition was evaluated as a mean value of 20 repeated experiments, there were 42% Gram-positive cocci, 37% Gram-positive rods, 3.5% Bacillus strains and 5.5% Gram-negative rods. Fluctuating values of cell amounts for Gram-positive cocci and rods during these experiments suggested that in the atmospheric layer near the ground, the former was a more transient group of airborne bacteria than the latter. When airborne bacterial flora over the experimental area was surveyed by observations at six stations, the dispersion profile of bacterial flora closely corresponded to vegetating states on the surface of the ground. Over vegetating areas, airborne bacterial flora appeared in about equal amounts of Gram-positive rods and cocci, while over bare ground, Gram-positive rods appeared more abundantly than Gram-positive cocci. To investigate the distribution of drug-resistant strains among airborne bacteria, sensitivity tests to six antibiotics were carried out with S. xylosus strains isolated at stations P and E. As a result, considerable amounts of single-drug-resistant strains for TC (DOX) and EM were recognized, but the distribution of multiple-drug-resistant S. xylosus was restricted to a few strains.

Air Microbiology↗
PubMed1989

[Study on hybrid materials compounded with porous hydroxyapatite and culture cells. 1. Attachment and the invasion of cultured cells to porous hydroxyapatite].

The purpose of this study was to investigate the effects of hybrid material compounded with periodontal ligament cells on human teeth and porous hydroxyapatite. As the first step, we tried to produce hybrid materials compounded with periodontal ligament cells and porous hydroxyapatite, and to observe the attachment and invasion of periodontal ligament cells porous hydroxyapatite. Human periodontal ligament cells which had been scraped off the root with a disposable blade were cultured at 37 degrees C in alpha-MEM plus 10% fetal calf serum. The culture cells were attached to the porous hydroxyapatite in vitro. After 3 and 14 days of incubation, the specimens were fixed in gluteraldehyde and examined using SEM. Other specimens were embedded in paraffin and successive specimens were prepared for to remodelling of the attachment and invasion. Many cells attached to the P-HAP granules, and some cells invaded the P-HAP granules. The results suggest that when these hybrid materials are implanted in bone defects, the cells remain in the defect for a certain period, and exhibit the functions and characteristics of itself.

Bone Regeneration↗
PubMed1989

[The plasma levels of haloperidol and reduced haloperidol in Japanese psychiatric patients].

We measured plasma levels of haloperidol (HAL) and its metabolite, reduced haloperidol (RHAL), in 30 psychiatric patients receiving haloperidol. HAL and RHAL levels were measured by reversed-phase high-performance liquid chromatography. The results were as follows. (1) Plasma levels of HAL had a highly positive correlation with daily dose per body weight (r = 0.902). (2) Distribution of individuals in relation to RHAL levels appeared to have a bimodal pattern. Of these 30 patients studied, 7 were identified as extensive metabolizers (23%). (3) RHAL/HAL ratios showed small intra-individual variance, while inter-individually they varied largely. The mean RHAL/HAL ratio in 30 patients was 0.692; when the 7 extensive metabolizers were excluded, it was 0.491. (4) In the individuals with clinical improvements, plasma levels of HAL and RHAL were 7.45 +/- 4.46, 3.96 +/- 2.16 ng/ml (mean +/- SD), respectively. Patients showing high plasma levels of HAL and RHAL (greater than 30 ng/ml) became aggravated during HAL treatment.

Adolescent↗
PubMed1988

Whole-cell and unitary Ca channel currents in mammalian intestinal smooth muscle cells: evidence for the existence of two types of Ca channels.

Whole-cell and single Ca channel currents were recorded in smooth muscle cells isolated from guinea-pig taenia coli to examine whether multiple types of Ca channels exist. Two different types of voltage-dependent Ca channels with different conductances and inactivation kinetics were identified from cell-attached patch clamp recordings using 50 mM Ba in the patch pipettes. One type of channel, with a large conductance of 25 pS, had a threshold of activation near -40 mV and the mean current reconstructed by averaging individual current responses inactivated slowly. A second type of channel, with a small conductance of 12 pS, had a similar threshold value to that of the 25 pS channel, but the averaged current inactivated rapidly. The steady state inactivation of the 12 pS channel was complete at a holding potential of -40 mV. We concluded that both channel types represent fast and slow inactivating voltage-dependent Ca channels which have been found in many excitable cells.

Animals↗
PubMed1986

HLA-DR2 and Dw2 in narcolepsy and in other disorders of excessive somnolence without cataplexy.

Studies on HLA antigens were conducted in several patient populations with the following findings: (a) All 135 Japanese narcoleptic patients, eight of whom were considered to have "symptomatic" narcolepsy, were found to be HLA-DR2 and HLA-DQw1 positive. All 17 members of a subgroup of the original population were also found to be HLA-Dw2-positive. It was concluded that HLA-DR2 is a prerequisite for the development of narcolepsy and that the diagnosis of narcolepsy can be excluded if HLA-DR2 or HLA-Dw2 is negative. The distinction between idiopathic and symptomatic narcolepsy needs to be reconsidered. (b) Haplotype studies in three families with narcoleptic members enabled detection of children at high risk for narcolepsy. (c) Of the 54 patients with disorders of excessive daytime sleepiness other than narcolepsy, those with essential hypersomnia (EHS) had a higher frequency of HLA-DR2; the others had a lower frequency. The DR2-positive EHS group could include members with an incomplete form of narcolepsy; the DR2-negative EHS group had disorders essentially different from narcolepsy, although both positive and negative groups manifested hypnagogic hallucinations, sleep paralysis, and sleep onset REMs. Two further studies were conducted in subgroups of the original narcoleptic population studied. In a subgroup of 30 patients who underwent lymphocyte subset studies, no T-cell abnormalities were detected; it is unlikely that an autoimmune mechanism is involved in the development of narcolepsy. In a subgroup of 33 narcoleptic patients, Southern's blot analysis of DNA using a DQ beta probe revealed three specific restriction fragments. Further studies are necessary to locate the DNA locus that carries the susceptibility gene for narcolepsy.

Alleles↗