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Biomedical subjects

M Katayama

Publications and source records attributed to M Katayama.

At least 343 records · Page 19Linked to original sources

Inhibitors on an elastase-like enzyme activity catalyzing Suc-Ala-Ala-Pro-Leu-pNA amidolysis in human seminal plasma.

The behavior of some proteinase inhibitors toward the Suc-Ala-Ala-Pro-Leu-pNA amidolytic enzyme activity in human seminal plasma (HSP) was tested. [(2S, 3R)-3-Amino-2-hydroxy-5-methyl-hexanoyl]L-valyl-L-valyl-L-aspartic acid (Amastatin) and 3-[1-[(2-(hydroxymethyl)- -pyrolidinyl)-2-methylpropyl]-carbamoyl] octanohydroxamic acid (Actinonin) showed strong inhibitory effects. No inhibition of this present enzyme activity was seen with anti-human serum (whole), anti-human leukocyte elastase, phenyl-methyl sulfonyl fluoride, Elastatinal, ethyeneglycol bis(beta-aminoethyl ethyl)N,N,N:N'-tetra acetic acid, and [L-3-trans-ethoxycarbonyl-oxirane-2-carbonyl]1-L-leucine(3-methylbutyl)a mido (E-64). No relation was observed between human pancreatic elastase antigen and the Suc-Ala-Ala-Pro-Leu-pNA amidolytic enzyme enzyme activity in HSP. Two peaks of Suc-Ala-Ala-Leu-Pro-pNA amidolytic enzyme activity were separated by Cellulofine GCL-2000 gel filtration and these activities were completely abolished by addition of Amastatin. Suc-Ala-Ala-Pro-Leu-pNA amidolytic enzyme activity in HSP is not an elastase-like metalloproteinase but is rather an acyl amidase-like leucine aminopeptidase.

Amidohydrolases↗

Blood coagulation factor X (FX) in human seminal plasma.

The active form of human blood coagulation factor X (FXa, EC 3.4.21.6) showing N-alpha-Benzoyl-L-isoleucyl-L-glutamyl-L-glycyl-L-arginine- p-nitroanilide (S-2222) hydrolyzing activity was first detected in human semen (seminal plasma) by affinity chromatography using anti-human coagulation factor X, and this enzyme activity was inhibited by anti-human FX. This enzyme has been associated with the human coagulation factor X (FX) in human semen (seminal plasma) by Western blot analysis, and the molecular mass of mature FX was also estimated to be 59 KDa by SDS-PAGE and Western blot analysis.

Blotting, Western↗

Action of physiologically active materials in human semen during aging.

We examined the activities of some physiologically active substances (enzymes) in human seminal plasma from subjects in their 20s, 30s, and 40s. The average volume of semen per ejaculation in this investigation did not differ significantly depending on the age of the subject. Two age dependent patterns of decrease of substances in semen were observed, and the substances including tissue kallikrein and prostate specific antigen (PSA) basic arginine amidase in human seminal plasma showing the first pattern (a significant decrease in the 40s as compared to the 30s) might be initially secreted from the prostate gland, and whereas the glands secreting the other group of substances including active form coagulation factor X (FXa) and plasminogen are not now known. The levels of these substances in semen decrease in the subjects in their 30s. The coagulation and liquefaction times of human semen from older subjects were both prolonged with those of semen from younger subjects, and that such alteractions ultimately cause the age dependent declines of the motility of sperm and the ability of fertility.

Adult↗

Amidolytic activities and prostate-specific antigen in human seminal plasma.

The amounts of protein measured by absorbance at 280 nm, succinyl-L-alanyl-L-alanyl-L-prolyl-L-leucine-p-nitroanilide (Suc-Ala-Ala-Pro-Leu-pNA), D-valyl-cyclohexyl-alanyl-L-arginine-p-nitroanilide (Val-CHA-Arg-pNA), and glutamyl-L-phenylalanine-p-nitroanilide (Glu-Phe-pNA) amidolytic activities, and prostate-specific antigen (PSA) were measured in human seminal plasma (HSP) samples separated from the semen of 46 cases, including 13 cases of azoospermia and 33 cases of normozoospermia showing either good or poor quality of liquefaction. There was a highly significant correlation between the concentrations of all amidolytic enzyme activities studied and the concentration of PSA in HSP samples (p<.01). The HSP sample volume showed a relatively good negative coefficient of correlation to all items measured (p<.01) with the exception of protein concentration. The Suc-Ala-Ala-Pro-Leu-pNA, Val-CHA-Arg-pNA, and Glu-Phe-pNA amidolytic activities in azoospermia HSP samples were 2.33. 1.68, and 1.43 times higher, respectively, than those of normozoospermia samples showing good quality liquefaction. After the addition of morphologically purified human sperm to HSP sample of azoospermia cases, the Suc-Ala-Ala-Pro-Leu-pNA amidolytic activity in the HSP sample of azoospermia was not decreased for up to 18 h incubation, while the number of motile human sperm gradually declined, and no motile human sperm were detected after 18 h of incubation. The high Suc-Ala-AlaPro-Leu-pNA amidolytic activity in HSP samples of azoospermia cases did not result from a lack of motility.

Amidohydrolases↗

CT findings in hepatic and splenic amyloidosis.

In a patient with biopsy proven focal amyloidosis of the liver CT showed a uniform decrease in attenuation, with a focal large low-density lesion in the right hepatic lobe. Following intravenous contrast medium injection, there was poor contrast enhancement.

Amyloidosis↗

Effect of ketone bodies on hyperglycemia and lactic acidemia in hemorrhagic stress.

BACKGROUND: To investigate the effect of hyperketonemia on altered glucose metabolism under stress conditions, we infused sodium D-3-hydroxybutyrate (3-OHB) into rats in hemorrhagic hypotension and evaluated the plasma concentration of substrates related to glucose metabolism. METHODS: Three groups of anesthetized rats (weight, 280 g to 320 g) were bled acutely, and their mean arterial pressures were maintained at 40 mm Hg. From 1 hour before hemorrhage to the end of the experiment, rats in the first group (n = 10) were infused with 3-OHB at a rate of 30 mumol/kg.min (3-OHB group), those in the second group (n = 10) received glucose and sodium bicarbonate (glucose group), and the remaining 10 rats received only sodium bicarbonate and no energy substrates (control group). Sodium bicarbonate was used to control the alkalizing effect of 3-OHB. RESULTS: Hyperketonemia (1158 +/- 30 mumol/L - 1618 +/- 154 mumol/L) occurred only in the 3-OHB group. Hyperglycemia and lactic acidemia during hemorrhagic shock were suppressed significantly compared with the control group. Plasma concentration of alanine was also lower compared with the control group. In the glucose group, although plasma lactate concentration was lower, plasma glucose concentration was not suppressed, and plasma alanine concentration was higher in comparison with the control group during hemorrhagic shock. There was no significant difference in plasma insulin concentration among the three groups. CONCLUSIONS: These results suggest that administered 3-OHB may suppress glycolysis during hemorrhagic shock.

3-Hydroxybutyric Acid↗

Miniature membrane oxygenator for use in neonatal ECMO.

A new miniature membrane oxygenator (Kuraray KMO, size, 0.3 m2, with a priming volume of 47 ml, compliance of less than 0.1 ml/100 mmHg, and pressure loss of 45 mmHg) with improved gas transfer and mechanical durability was developed and tested. The membrane material is a hollow fiber double layer polyolefin. The testing procedures determined by the AAMI were followed, and the results showed improved O2 and CO2 transfer (70 ml/min and 55 ml/min, respectively). Hemolysis was within acceptable limits, and plasma leakage was undetectable after 7 days of perfusion. Clinical study demonstrated satisfactory performance.

Carbon Dioxide↗

Magnetic field of atrial depolarization.

The isomagnetic maps of normal subjects and patients with right and left atrial overloading were recorded to determine the characteristic features of the magnetic field of atrial depolarization. The isomagnetic maps examined in this study indicated the instantaneous current source, which specifically localizes the current sources due to the right and left atria, respectively. The magnetic field recorded with a second derivative gradiometer clearly detected the cardiac current source from the right atrium, which is located close to the anterior chest wall, thus this method improved the diagnostic sensitivity for right atrial overloading. In patients with left atrial overloading, the isomagnetic map showed multiple dipoles due to the right and left atria, respectively, which are difficult to be detected by the electrocardiogram or isopotential map. These results suggest that the magnetocardiogram provides useful information on the current source to supplement information obtained by the conventional electrocardiogram.

Adult↗

Prognostic significance of hst-1 gene amplification in primary esophageal carcinomas and its relationship to other prognostic factors.

We studied hst-1 gene amplification in 50 primary human esophageal carcinomas using Southern blot analysis. We found 3- to 9-fold amplification of the hst-1 gene in 15 out of 50 (30.0%) DNA samples from primary tumors. There was no evidence of a correlation between hst-1 gene amplification and several prognostic factors other than the histological type; hst-1 gene amplification was more common in well differentiated squamous cell carcinoma. Survival rates for patients bearing tumors with and without hst-1 gene amplification were calculated by the Kaplan-Meier method and evaluated by the log-rank test. The survival curves for the two groups were almost identical. These results suggest that amplification of the hst-1 gene is a poor indicator of the prognosis of patients who have undergone surgery for primary esophageal carcinoma.

Adult↗