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Biomedical subjects

M Oguchi

Publications and source records attributed to M Oguchi.

At least 73 records · Page 4Linked to original sources
PubMed1989

The increase of non-MHC-restricted cytotoxic cells (gamma/delta-TCR-bearing T cells or NK cells) and the abnormal differentiation of B cells in Wiskott-Aldrich syndrome.

The objective of this study was to analyze the configuration of the lymphocytes in Wiskott-Aldrich syndrome (WAS) by studying the surface antigens from nine cases using dual-color immunofluorescence analysis. All the patients showed the increase of non-MHC-restricted cytotoxic cells, namely CD3+ WT31- delta TCS1+ (gamma/delta-T cell receptor (TCR)-bearing cells) and/or CD16+ natural killer cells. The gamma/delta-TCR+ cells of WAS, however, were unique since they did not express CD5, which is present on ordinary gamma/delta-TCR+ cells. A reduced number of CD4+ cells and an increased percentage of CD11b+ Leu7+ cells within a CD8+ subset were observed in all cases. With regard to B cell subpopulations, most cases showed reduced Fc epsilon R2-bearing B cells, despite an elevated serum IgE.

Adolescent↗
PubMed1989

Met-enkephalin, injected during the early phase of stress, attenuates stress-induced increases in noradrenaline release in rat brain regions.

By measuring levels of 3-methoxy-4-hydroxyphenylethyleneglycol sulfate (MHPG-SO4), the major metabolite of noradrenaline (NA), we investigated the effects of Met-enkephalin (Met-ENK) ICV injected at three different stages of stress, i.e., 0 min, 5 min, or 10 min after exposure to immobilization stress. Immobilization stress caused significant increases in MHPG-SO4 levels in all brain regions examined, i.e., the hypothalamus, amygdala, thalamus, midbrain, hippocampus and locus coeruleus (LC), which suggests that stress increases NA release in these regions. Met-ENK at a dose of 50 micrograms, injected ICV immediately before stress exposure significantly attenuated stress-induced increases in MHPG-SO4 in the amygdala, thalamus and LC, but did not have such an effect when injected either 5 min or 10 min or 10 min after exposure to stress. Similarly, Met-ENK at 150 micrograms at 0 min significantly attenuated these increases in all brain regions examined, however, it did not do so when given at 5 min or 10 min after stress initiation. The amount of defecation and the weight loss caused by stress were also significantly attenuated by Met-ENK injected but only at 0 min. These results suggest that the attenuating effect of Met-ENK on stress-induced increases in NA release is greatly affected by the time of the peptide administration and that Met-ENK might inhibit stress-induced increases in NA release in these regions by affecting the initial changes induced by stress.

Animals↗
PubMed1989

Closed and continuous algae cultivation system for food production and gas exchange in CELSS.

In CELSS (Controlled Ecological Life Support System), utilization of photosynthetic algae is an effective means for obtaining food and oxygen at the same time. We have chosen Spirulina, a blue-green alga, and have studied possibilities of algae utilization. We have developed an advanced algae cultivation system, which is able to produce algae continuously in a closed condition. Major features of the new system are as follows. (1) In order to maintain homogeneous culture conditions, the cultivator was designed so as to cause a swirl on medium circulation. (2) Oxygen gas separation and carbon dioxide supply are conducted by a newly designed membrane module. (3) Algae mass and medium are separated by a specially designed harvester. (4) Cultivation conditions, such as pH, temperature, algae growth rate, light intensity and quantity of generated oxygen gas are controlled by a computer system and the data are automatically recorded. This equipment is a primary model for ground experiments in order to obtain some design data for space use. A feasibility of algae cultivation in a closed condition is discussed on the basis of data obtained by use of this new system.

Biomass↗
PubMed1989

Regressing ulcerative histiocytosis.

A 15-year-old girl presented with many round to oval erythematous indurated plaques on the trunk, scalp, and proximal portion of the extremities. The individual lesions showed ulceration within a short period but spontaneously healed after 2 or 3 months. The main histological feature was dermal proliferation of rather mature histiocytes that were regarded as neither inflammatory nor neoplastic, with subsequent destruction of normal dermal tissue architectures. Lymph nodes, bone marrow, and internal organs were not involved. The lesions were improved neither by potassium iodide therapy nor by combined therapy of corticosteroid and cyclophosphamide, but the patient recovered by clofazimine after a 2-year course. We considered this case to be an unusual form of cutaneous histiocytic proliferation, which we tentatively termed "regressing ulcerative histiocytosis."

Adolescent↗
PubMed1988

Expression of aggression attenuates stress-induced increases in rat brain noradrenaline turnover.

This experiment determined whether or not an aggressive biting response could attenuate stress-induced increases in brain noradrenaline (NA) turnover, by measuring contents of NA and its major metabolite, 3-methoxy-4-hydroxyphenylethyleneglycol sulfate (MHPG-SO4), in discrete brain regions of male Wistar rats. Rats were exposed to a 10 min supine restraint stress with or without being allowed to bite a wooden stick. In each group, the animals were sacrificed by decapitation either 0 min or 50 min after release from stress. NA and MHPG-SO4 levels were unaffected in both biting and non-biting groups immediately after stress, as compared to controls. Fifty min after release from stress, increases in plasma corticosterone levels induced by stress recovered in the biting group but remained high in the non-biting group. MHPG-SO4 levels significantly increased in the hypothalamus, amygdala, thalamus, midbrain, basal ganglia, hippocampus and cerebral cortex in both stressed groups, however the increases in the non-biting group were significantly higher than those in the biting group in the first 5 of these regions. These findings clearly show that giving rats an opportunity to express aggression during stress exposure results in a significant attenuation of stress-induced increases in NA turnover in specific brain regions, such as the hypothalamus and limbic areas. The present experiment provides a possible neurochemical basis for clinical studies showing that suppression of anger in a stressful, frustrating situation leads to pathological consequences in humans.

Aggression↗
PubMed1988

Is immobility of rats in the forced swim test "behavioral despair"?

Rats were forced to swim in a cistern until sinking in order to examine the possible relationship between sinking and immobility which has been reported to reflect "behavioral despair" in the forced swim test. Rats were classified into sinking and non-sinking groups, according to the appearance of sinking behavior over a 2 hr test. The sinking rats showed significantly shorter immobility times during the first 15 min as compared to the non-sinking rats. Therefore, sinking behavior seems to be a sign of emotional behavior such as fear and/or anxiety accompanied by defecation. Discriminant analysis showed that the immobility time during the first 15 min was a prediction of sinking. These findings suggest that the rapidly induced immobility in this forced swim test reflects the possibility of floating behavior in connection with the emotional reaction.

Animals↗
PubMed1988

Effect of acute ethanol administration on noradrenaline metabolism in brain regions of stressed and nonstressed rats.

The effects of ethanol on noradrenaline (NA) metabolism of brain regions in stressed and nonstressed rats were investigated. Male Wistar rats were injected IP with either saline, or ethanol at 0.5 g/kg or 2 g/kg, 5 min before exposure to 1-hr immobilization stress. Levels of NA and its major metabolite, 3-methoxy-4-hydroxyphenylethyleneglycol sulfate (MHPG-SO4) in various brain regions and plasma corticosterone levels were fluorometrically determined. Immobilization stress caused significant increases in MHPG-SO4 levels in all brain regions examined, i.e., the hypothalamus, amygdala, hippocampus, cerebral cortex and locus coeruleus (LC) region. In nonstressed rats, ethanol significantly increased MHPG-SO4 levels in the hypothalamus, hippocampus and cerebral cortex, but not in the amygdala or in the LC region. In stressed rats, ethanol attenuated stress-induced increases in MHPG-SO4 levels preferentially in the amygdala and LC region, but not in the remaining three regions. Although ethanol per se dose-dependently elevated plasma corticosterone levels in nonstressed rats, ethanol at 2 g/kg attenuated the stress-induced elevation of corticosterone. These results suggest that the attenuating effect of ethanol on stress-induced increases in NA turnover in the amygdala and LC region might be related to the stress-relieving properties of this drug.

Animals↗
PubMed1988

The number and size of normal mediastinal lymph nodes: a postmortem study.

For the CT diagnosis of pathologically enlarged nodes, information concerning the size of normal nodes is required. We studied 40 adult cadavers and determined the number and size of normal lymph nodes for each region of the mediastinum, counting all nodes and directly measuring the short and long diameters of each in the transverse plane of the node. The location of each node was classified according to the American Thoracic Society system, and the range and standard maximum sizes of normal lymph nodes in each location were determined. Nodes were found in 90-100% of cadavers in regions 4, 7, and 10; and in 68-85% of cadavers in regions 2 and 6. The average number of lymph nodes found was 3.5-4.8 in regions 4, 6, and 10R; 2.1-2.9 in regions 2, 7, and 10L; and 0.1-1.2 in all other regions. The mean short transverse diameters ranged from 2.4 to 5.6 mm, and the mean long transverse diameters ranged from 3.9 to 10.0 mm. The largest mean short and long transverse diameters were found in region 7, the next largest were in region 10R, followed by regions 4, 5, and 10L. We noted a different maximum normal size of lymph nodes in each region of the mediastinum. The short transverse diameter, which showed a smaller variation, appeared to be a more useful parameter than the long transverse diameter. We propose a standard for maximum normal short transverse diameters for nodes in each region of the mediastinum as follows: 12 mm for nodes in region 7; 10 mm for nodes in regions 4 and 10R; and 8 mm for nodes in other regions. The maximum long transverse diameters showed a wider variation, ranging from 25 to 10 mm.

Female↗
PubMed1988

Ultrasonic evaluation of cervical metastatic lymphadenopathy.

We investigated the location, size, and shape of cervical lymph nodes in head and neck cancer, using a 7.5-MHz ultrasound scanner. First, the different criteria for normal size were obtained for cervical lymph nodes in each region; lymph nodes greater than 9 mm in thickness in the internal jugular chain or greater than 7 mm in thickness in the submandibular and submental chains should be suspected of harboring metastatic foci. Second, metastatic nodes showed a more rounded configuration than nonmetastatic ones. Third, a comparative study of metastatic lymph nodes between the in vivo and in vitro ultrasonograms and the corresponding histopathological findings disclosed that an echogenic region in an ultrasonogram of a metastatic node was caused by coagulation necrosis, and a cystic area of liquefaction necrosis.

Carcinoma, Squamous Cell↗
PubMed1988

Intracytoplasmic crystalline inclusions in dermal infiltrating cells of granulomatous contact dermatitis due to gold earrings.

A case of granulomatous contact dermatitis due to gold earrings for pierced ears was studied ultrastructurally. The patient was a 24-year-old woman, who had reddish brown papules on the earlobes. Patch test using gold sodium thiomalate proved strong positive, with blister formation. Histological observation of the papule showed dense cell infiltration throughout the full thickness of the dermis. Ultrastructurally, dermal infiltrating cells consisted of lymphocytes and histiocytes. Unusual crystalline inclusion bodies were observed in the cytoplasm of these cells. These structures were elliptical, not encapsulated and showed a regular fingerprint-like pattern of parallel lines along the short axis. The width of the lines and their intervals was 12 nm. These findings suggest that continuous contact between gold and dermis may induce inflammation, causing granulomatous changes and the development of crystalline inclusion bodies.

Adult↗
PubMed1988

[Recurrence of non-Hodgkin's lymphoma: local control failures and regional recurrences].

From 1972 to 1982, 563 patients with Stage I and II non-Hodgkin's lymphoma received radiation therapy in the department of radiology which belongs to the JLRTS group. Local control failures were seen in only 5 cases (0.9%). The regional recurrences were found in 30 cases (5%). 17 of recurrences occurred during the first 5 years. 17 cases had remissions again, and 5 cases had 5 year survivals.

Combined Modality Therapy↗
PubMed1987

Food production and gas exchange system using blue-green alga (Spirulina) for CELSS.

In order to reduce the cultivation area required for the growth of higher plants in space adoption of algae, which have a higher photosynthetic ability, seems very suitable for obtaining oxygen and food as a useful source of high quality protein. The preliminary cultivation experiment for determining optimum cultivation conditions and for obtaining the critical design parameters of the cultivator itself has been conducted. Spirulina was cultivated in the 6-liter medium containing sodium hydrogen carbonate solution and a cultivation temperature controlled using a thermostat. Generated oxygen gas was separated using a polypropyrene porous hollow fiber membrane module. Through this experiment, oxygen gas (at a concentration of more than 46%) at a rate of 100-150 ml per minute could be obtained.

Air Conditioning↗
PubMed1987

Fundamental study on gas monitoring in CELSS.

A mass spectrometer and computer system was developed for conducting a fundamental study on gas monitoring in CELSS. Respiration and metabolism of the hamster and photosynthesis of the Spirulina were measured in a combination system consisting of a hamster chamber and a Spirulina cultivator. They are connected through a membrane gas exchanger. Some technical problems were examined. In the mass spectrometric gas monitoring, a simultaneous multi-sample measurement was developed by employing a rotating exchange valve. Long term precise measurement was obtained by employing an automatic calibration system. The membrane gas sampling probe proved to be useful for long term measurement. The cultivation rate of the Spirulina was effectively changed by controlling CO2 and light supply. The experimental results are helpful for improving the hamster-spirulina system.

Air Conditioning↗
PubMed1987

The applicability of catalytic wet-oxidation to CELSS.

The wet-oxidation catalysis of Au, Pd, Pt, Rh or Ru on a ceramic honeycomb carrier was traced in detail by 16 to 20 repetitive batch tests each. As a result, Pt or Pd on a honeycomb carrier was shown to catalyze complete nitrogen gasification as N2. Though the catalysts which realize both complete nitrogen gasification and complete oxidation could not be found, the Ru+Rh catalyst was found to be most promising. Ru honeycomb catalyzed both nitrification and nitrogen gasification.

Bioreactors↗