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Biomedical subjects

H Katoh

Publications and source records attributed to H Katoh.

At least 415 records · Page 23Linked to original sources
PubMed1988

Intraoperative EEG monitoring: (I). Parametric representation of processed EEG during anesthesia.

One of the most common techniques of EEG monitoring during operations is to produce a three dimensional image by displaying the frequency distributions with respect to time as in compressed spectral array (CSA) and density-modulated spectral array (DSA). In order to characterize these images by numerical parameters, we defined two parameters; the percent spectral edge frequency as the frequency at which the one-sided-power sum reaches the designated percentage of the total; and the mean frequency as the power-weighted mean within the interval that includes a dominant spectrum in the frequency distribution. These parameters were superimposed on displays to characterize EEG changes, and they proved to be a very powerful tool to quantitate variations in data among anesthetic techniques and thus efficiently control the depth and duration of anesthesia. We report a number of actual cases.

Adult↗
PubMed1988

Intraoperative EEG monitoring: (II). Similarity analysis using density-modulated t array.

A method of showing the similarity, in other words, defining the difference between a pair of EEG patterns has been developed. By using the student t test on the power spectra at the appropriate frequency intervals, the t values obtained can be used as an indicator of the difference between the spectral patterns with respect to the frequency intervals. This so-called t-profile can be computed on real time basis and the result superimposed in different colors using the apparatus described previously to produce a 3-dimensional picture. We call this picture a density-modulated t array or DTA. Along with CSA and DSA (compressed/density-modulated spectral arrays), it proved to be a very powerful tool in intraoperative EEG monitoring.

Adult↗
PubMed1987

Effects of clofibric acid and tiadenol on cytosolic long-chain acyl-CoA hydrolase and peroxisomal beta-oxidation in liver and extrahepatic tissues of rats.

The effects of two peroxisome proliferators, p-chlorophenoxyisobutyric acid (clofibric acid) and 2,2'-(decamethylenedithio)diethanol (tiadenol), on cytosolic long-chain acyl-CoA hydrolase and peroxisomal beta-oxidation were studied in several organs of rat. Among organs of control rats, the brain had the highest activity of long-chain acyl-CoA hydrolase, followed by testis, and a low activity was found in other tissues. Administration of the peroxisome proliferators caused a marked increase in activity of long-chain acyl-CoA hydrolase in both liver and intestinal mucosa and a slight increase in the activity in kidney, but little affected acyl-CoA hydrolase activity in either brain, testis, heart, spleen and skeletal muscle. In accordance with the change in the activity of acyl-CoA hydrolase, the activity of peroxisomal beta-oxidation was markedly increased in liver, intestinal mucosa and kidney, and a slight increase was found in brain and testis, whereas peroxisome proliferators little affected the activity in other organs tested. Gel filtration of cytosol from intestinal mucosa showed that clofibric acid caused an appearance of a new peak in intestinal mucosa. Although cytosol of liver, intestinal mucosa, brain and testis contained two 4-nitrophenyl acetate esterases with different molecular weights (about 105,000 and about 55,000), these esterases are different from cytosolic long-chain acyl-CoA hydrolases of these four organs in respect of molecular weight. The administration of clofibric acid little affected cytosolic 4-nitrophenyl acetate esterases. Comparative studies on cytosolic long-chain acyl-CoA hydrolases from these four organs showed that liver hydrolase I (molecular weight of about 80,000) had properties similar to those of brain and testis enzymes. On the other hand, intestinal mucosa enzyme was different from either hepatic hydrolase I or II (molecular weight of about 40,000). The results from the present study suggest that inductions of peroxisomal beta-oxidation and cytosolic long-chain acyl-CoA hydrolases are essential responses of rats to peroxisome proliferators not only in liver but also in intestinal mucosa and that induced hydrolases are not attributable to non-specific esterases.

Animals↗
PubMed1987

Protection of liver cells against experimental damage by extract of cultured Lentinus edodes mycelia (LEM).

Liver cell damage can be induced when isolated liver cells coated with specific antibodies against the liver cell membrane are cultured with peripheral blood mononuclear cells. Although this antibody-dependent cell-mediated cytotoxicity (ADCC) is dependent on the close contact of effector cells with target cells via specific antibodies, a cytotoxic factor or factors causing the inhibition of protein synthesis in liver cells has been detected in the culture supernatant from the ADCC reaction. Similarly, peritoneal exudate macrophages activated by endotoxin lipopolysaccharide also exert cytotoxic effects on isolated liver cells by production of a cytotoxic substance or substances. The liver cell damage caused by either the ADCC or activated macrophage culture supernatants were significantly reduced by pretreating the isolated liver cells with the extract of cultured Lentinus edodes mycelia (LEM). These results suggest that LEM may protect liver cells from immunological damage.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1987

Effects of extract of cultured Lentinus edodes mycelia (LEM) on polyclonal antibody response induced by pokeweed mitogen.

When polyclonal antibody response induced by pokeweed mitogen (PWM) was estimated by measuring antibody-forming cells produced against trinitrophenylated sheep red blood cells (TNP-SRBC) using hemolytic plaque assay, it was found to be augmented by the extract of cultured Lentinus edodes mycelia (LEM). Since some factor enhancing antibody response was detected in the culture supernatant of LEM-treated macrophages, this was fractionated by gel filtration, which revealed a substance with a molecular weight of about 15,000 daltons. This suggested that interleukin-1 (IL-1) was produced, and that it had caused, at least partially, the enhancement of antibody response. This possibility was confirmed by the direct assay of IL-1 activity, which demonstrated increased DNA synthesis in PHA-stimulated thymocytes.

Animals↗
PubMed1987

Coagulability and fibrinolytic changes during veno-venous bypass in liver transplantation.

In clinical liver transplantation, a venous bypass that rechannels the blood flow from the inferior vena cava and portal vein to the superior vena cava has been used to maintain the venous return. However, the usage of mechanical shunt has given rise to derangements of blood coagulability and fibrinolysis. Therefore, changes of coagulability and fibrinolysis during the venous bypass were examined in dogs using a centrifugal pump (Bio-Pump), and the effect of gabexate mesilate for coagulation were studied. Venous bypass from the inferior vena cava and the portal vein to the external jugular vein was performed in mongrel dogs (group A: bypass without pump, group B: bypass with the Bio-Pump, group C: bypass with the Bio-Pump and the addition of gabexate mesilate). In group A, blood pressure gradually decreased, but in groups B and C it maintained the pre-bypass level. All results of coagulation parameters and fibrinolytic measurements of group B were not significantly different from those of group A; only partial thromboplastin time was prolonged in group B. However, this prolongation was effectively prevented by the addition of gabexate mesilate in group C.

Animals↗
PubMed1987

Hyperthyroidism associated with autoimmune hemolytic anemia and periodic paralysis: a report of a case in which antihyperthyroid therapy alone was effective against hemolysis.

We describe a case of a 29-year-old man with hyperthyroidism associated with autoimmune hemolytic anemia and periodic paralysis. Euthyroidism, which was achieved by propylthiouracil, brought inhibition of hemolysis and amelioration of anemia in spite of continuously positive direct and indirect Coombs' tests. Neither adrenocortical steroid nor blood transfusion was administered. Since indirect monospecific Coombs' test was negative against anti-human complements serum, the membrane of red blood cells may be less fragile. This is one reason why hemolysis was inhibited by anti-hyperthyroid therapy only. This may indicate that the hyperdynamic circulatory state secondary to hyperthyroidism plays an important role in the destruction of red blood cells which were coated by anti-red blood cell antibody.

Adult↗
PubMed1987

[Triple primary malignancies (malignant melanoma, laryngeal cancer and hepatoma)].

A 61 year-old male patient, diagnosed to have a malignant melanoma in the left arm in April, 1981, was treated by chemotherapy (gamma-INF and DAVP) and a left axillary lymphadenectomy. In March, 1985, he had complained of hoarseness and an early laryngeal squamous cell carcinoma was found, and was subjected to laser treatment. On May 25, 1986, during his hospitalization for treatment of a multiple metastasis of a malignant melanoma, he suddenly suffered from a gastroduodenal perforation. During an emergency operation, a third cancer, a primary mixed hepatocellular and cholangiocellular carcinoma, was discovered.

Carcinoma, Hepatocellular↗
PubMed1987

[Small-cell carcinoma of the lung relapsing at the primary site three years after radiation therapy with chemotherapy].

A 55-year-old man was diagnosed as having limited disease (T2N2M0, stage III) of small-cell carcinoma of the lung. He underwent radiation therapy (60 Gy in 30 fractions) in addition to combination chemotherapy, resulting in complete response with advantage for irradiation. Relapse in the primary site was seen three years after completion of the initial treatment. As a result, retreatment was started using radiation therapy (50 Gy in 25 fractions) with chemotherapy. The tumor almost disappeared again. Subsequently, cerebral metastasis was observed in the fourth year, indicating clinical and prognostic significance. Thoracic irradiation contributed to prolonged survival in this case. The most effective manner of combining irradiation and chemotherapy and the most efficacious doses were discussed.

Carcinoma, Small Cell↗