PubMed Health⌕ Search

Biomedical subjects

M Sakaguchi

Publications and source records attributed to M Sakaguchi.

512 records · Page 29Linked to original sources
PubMedDate not supplied

Neurotological evaluation of vertical semicircular canal function in inner ear malformation. A case report.

A 9-year-old boy with inner ear malformation complained of slight deafness and unsteadiness. CT revealed a normal cochlea despite enlargement of the lateral semicircular canals. The vertical semicircular canals developed more or less normally. The caloric test showed complete canal paresis bilaterally; however, a horizontal rotational stimulus elicited a vestibulo-ocular response, which showed only rightward and downward nystagmus, and their maximal slow-phase velocities were low. In addition, the examination of the vertical semicircular canal function using the head-tilted rotation test revealed a more active response, and the maximal slow-phase velocities were higher than those of a standard horizontal rotational test. These results suggest that the function of the vertical semicircular canal was well preserved and that it may have perceived the horizontal acceleration instead of the lateral semicircular canal.

Audiometry, Pure-Tone↗
PubMedDate not supplied

Hyperthermia enhances the cytotoxicity against hypoxic cells of RP-170, a new 2-nitroimidazole nucleoside hypoxic cell sensitizer.

The effect of the new hypoxic cell sensitizer, 1-[2-hydroxy-1-(hydroxymethyl)-ethoxy]methyl-2-nitroimidazole (RP-170), combined with heat against EMT6/KU cells, was determined under conditions of in vitro hypoxia. Heat-induced cytotoxicity for the EMT6/KU cells was increased to a greater extent under conditions of hypoxia and a normal pH of the medium. Hypoxia also reduced the surviving fraction of the cells treated either with RP-170 alone or with RP-170 plus heat. The concomitant treatment of RP-170 and heat inhibited the clonogenic activity of the EMT6/KU cells under conditions of in vitro hypoxia in all experimental groups, with a significant difference (p < 0.05). Therefore, RP-170 combined with exposure to heat may be an effective treatment for hypoxic cells in a solid tumor, as these cells are resistant to radiation and/or to many chemotherapeutic agents.

Animals↗
PubMedDate not supplied

Treatment of surgically induced acute liver failure with transplantation of highly differentiated immortalized human hepatocytes.

Primary human hepatocytes are an ideal source of hepatic function in bioartficial liver (BAL), but the shortage of human livers available for hepatocyte isolation limits this modality. To resolve this issue, primary human fetal hepatocytes were immortalized using simian virus 40 large T antigen. One of the immortal cell lines, OUMS-29, showed highly differentiated liver functions. Intrasplenic transplantation of OUMS-29 cells protected 90% hepatectomized rats from hyperammonemia and significantly prolonged their survival. Essentially unlimited availability of OUMS-29 cells supports their clinical use for BAL treatment.

Ammonia↗
PubMedDate not supplied

Laser Doppler assessment of human colonic blood flow.

We have used laser Doppler flowmetry to assess human colonic blood flow in patients with healthy mucosa and in those with active proctitis. We report a significant correlation between colonic serosal laser Doppler flux readings and serosal tissue oxygen tension (n = 45: r = 0.671: p = 0.001). Mucosal blood flow was measured using the PF309 probe of a Perimed Pf2b set on 12 kHz frequency shift. There was no significant difference throughout the colon in healthy patients. The flow in rectal mucosa was significantly higher in patients with proctocolitis than in normal mucosa.

Colon↗
PubMedDate not supplied

Effects of dietary N-3 and saturated fats on growth rates of the human colonic cancer cell lines SW-620 and LS 174T in vivo in relation to tissue and plasma lipids.

Ninety nude mice were inoculated subcutaneously with 1 x 10(7) cells of the human colonic cancer cell lines, SW-620 and LS174T. Tumour growth was assessed weekly for three weeks whilst the animals were receiving one of three diets: control (4.6% fat), coconut (20% fat, saturated fatty acids) and Maxepa (20% fat; n-3 fatty acids). At the end of the study SW-620 tumour weights (mean +/- SD, gm) were: control = 0.38 +/- 0.22, coconut = 0.43 +/- 0.31, Maxepa 0.20 +/- 0.16; the LS174T tumour weights were control = 1.33 +/- 1.27, coconut = 0.47 +/- 0.74, Maxepa = 0.38 +/- 0.56 (p less than 0.001, analysis of covariance). The Maxepa diet produced significant retardation in tumour growth (p less than 0.001). This was associated with reduced levels of linoleic acid and arachidonic acid in adipose tissue and tumour lipids with incorporation of n-3 fatty acids (all p less than 0.01 at least, analysis of variance). Moreover, the Maxepa diet produced significant reductions of plasma cholesterol, phospholipids and triglycerides (all p less than 0.01).

Adipose Tissue↗
PubMedDate not supplied

Histamine release from pulmonary mast cells after lung transplantation in rats.

BACKGROUND AND METHODS: On the assumption that lung mast cells might respond and release histamine after lung transplantation, the number of mast cells and tissue histamine content were investigated for 2 weeks after rat orthotopic left lung isotransplantation (Lewis rat to Lewis rat) and allotransplantation (Lewis rat to Brown Norway rat). The allografts were rejected histologically by day 7 (grade A4). RESULTS: In the isografts, both the numbers of mast cells and histamine content were lower (p < 0.05) on day 4 but higher (p < 0.001) on day 14 compared with the nontransplanted donor left lungs (control). In the allografts, the numbers of mast cells on day 7 and histamine content on day 1 were lower (p < 0.05) than controls and both continued to be low thereafter. On day 7, the histamine content of the allografts was low (p < 0.05) compared with the level of the isografts. Conversely, no significant change was found in histamine content of the untransplanted right native lungs except for on day 14 after isotransplantation, when the content was higher than the controls, suggesting the possibility of a systemic signal for proliferation of mast cells. CONCLUSIONS: Our data indicated that degranulation of the pulmonary mast cells and consequent histamine release localized in the grafts occurred under the microenvironment of reimplantation and rejection after rat lung transplantation.

Animals↗
PubMedDate not supplied

Pharmacological characteristics of Sho-seiryu-to, an antiallergic Kampo medicine without effects on histamine H1 receptors and muscarinic cholinergic system in the brain.

The pharmacological characteristics of Sho-seiryu-to, an antiallergic Kampo medicine, were investigated. Forty-eight-hour passive cutaneous anaphylactic (PCA) reaction was significantly inhibited in rats orally administered Sho-seiryu-to (1000 mg/kg). Sho-seiryu-to significantly inhibited increase in vascular permeability induced by histamine. These data confirm previous findings that Sho-seiryu-to has antiallergic activity in animals and suggest that the antagonism of histamine may be an antiallergic mechanism of Sho-seiryu-to. Sho-seiryu-to did not affect locomotor activity or motor coordination in mice. Although ketotifen prolonged sleeping time induced by pentobarbital, Sho-seiryu-to had no such effect. Nor was there any effect on oxotremorine-induced tremor and [3H]-mepyramine binding to histamine H1 receptors in rat brain. Thus, Sho-seiryu-to appears to be useful for treating type I allergy, with relatively few side effects such as sedation and drowsiness due mainly to blockade of histamine H1 and muscarinic receptors in the brain.

Animals↗