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Biomedical subjects

Y Kikuchi

Publications and source records attributed to Y Kikuchi.

At least 847 records · Page 47Linked to original sources

[Diagnostic value of biochemical tumor markers in serum of patients with cancer of the ovary].

A comparison of several serum tumor markers (lactate dehydrogenase (LDH), LDH isozyme, hydroxybutylrate dehydrogenase (HBD), alkaline phosphatase (ALP), cholinesterase (Choline-E), aldolase (ALD), leucine aminopeptidase (LAP), gamma-glutamyl transpeptidase (gamma-GTP), human chorionic gonadotropin (HCG), carcinoembryonic antigen (CEA) and alpha 1-fetoprotein (AFP)) was made in patients with carcinoma or benign tumor of the ovary and healthy control subjects. The greatest positive rates were obtained with the markers HBD (76.5%) and Choline-E (73.3%) for patients with carcinoma of the ovary, respectively. However, based on false positive results, Choline-E was also greatest (50.0%) for patients with benign tumor of the ovary. The lowest false positive rates were obtained with ALD, but the positive rates for patients with stage I and II diseases were 0.0%. The most suitable single marker for patients with stage I and II diseases was HBD (62.5%), followed by LDH (41.7%). Three of 4 patients with early cancer, who had normal serum LDH levels, showed abnormal LDH isozyme patterns (elevated LDH-4 and -5). A combination of LDH activity and LDH isozyme resulted in an increase in the positive results (41.7% to 70.0%), that is, the cancer patients were positive for one of the two markers. For CEA, AFP and HCG, the positive results were 26.9%, 19.0% and 7.1%, respectively. Positive and false positive rates for ALP were 36.7% and 7.1%, but the positive rates in the early stage were lower (14.3%), compared to those for LDH and HBD. HBD and LDH activities in the ovarian malignant tissues and ascitic fluids were significantly higher than those in the benign tumor tissues and ascitic fluids, resulting in a significant elevation of serum LDH and HBD levels in the patients. Moreover, it was suggested that inhibition test of ALP by the inhibitors might be able to identify the tissue origin of ALP in the cancer patients.

Carcinoembryonic Antigen↗

[Clinical evaluation of serum CEA levels in uterine cervix cancer].

Serum CEA levels were measured in the blood of 98 patients with uterine cervix cancer before, during, and after treatment to investigate the relationship among the CEA level, the extent of the disease, and recovery. The CEA level rose as the disease progressed. Although there was no significant difference in the survival rates of patients with various CEA levels, those who returned to normal levels after treatment recuperated better. There was not clear evidence that CEA levels are clinically significant. However, it can be concluded that CEA levels at pre- and post-treatment times are helpful in the early detection of disease, prognosis, and in predicting recurrence or metastasis.

Carcinoembryonic Antigen↗

Circularization of linear viroid RNA via 2'-phosphomonoester, 3', 5'-phosphodiester bonds by a novel type of RNA ligase from wheat germ and Chlamydomonas.

A novel type of RNA ligase activity in extracts of wheat germ or Chlamydomonas requires 2', 3'-cyclic phosphate and 5'-phosphate ends for ligation to form a 2'-phosphomonoester, 3',5'-phosphodiester bond. Using 5'-3 2P-labeled linear PSTV, we demonstrate that RNase T1-nicked viroid predominantly forms (formula; see text) U-bonds. Natural linear PSTV, however, forms mainly (formula; see text) A-bonds upon enzymatic circularization. We show that natural linear PSTV RNA has nicks between C181 and A182, or between C348 and A349, and that consequently C181 and C348 carry 2',3'-cyclophosphate termini.

Chemical Phenomena↗

Preocclusive perfusion area as a determinant of infarct size in a canine model.

The extent of myocardial infarction related to the pre-occlusive perfusion are was quantitatively evaluated in a canine model. The perfusion area was determined preocclusively by selective injection of tracer microspheres into the coronary artery in question, then the main trunk and a small lateral branch of the left circumflex coronary artery was occluded in group 1 (10 dogs) and group 2 (10 dogs), respectively. Rapid freezing was used to prepare autoradiographic samples for determination of the perfusion are along with samples for dehydrogenase staining in order to delineate the extent of myocardial infarction. The relationship between perfusion area and infarct size was examined in 50 micrometers thick samples from base, middle and apex of the ventricle and a direct linear correlation between the perfused (P) and infarcted area (I) in the left ventricle (LV) was noted regardless of the perfusion size or the location in the ventricle. The linear relationship I = 0.93P - 4.9 (r = 0.95, P less than 0.001) was obtained in all 20 dogs. Transmural extent of necrosis was larger in the endocardium than in the epicardium, thereby representing a more salvageable myocardium in the epicardium. It is concluded that the preocclusive determination of perfusion are by high resolution autoradiography is a useful method of obtaining physiological perfusion not affected by ischaemia. Also the infarct size when standardized by the perfusion area is mainly influenced by transmural location but not by the spacial geometry or the size of the occluded area.

Animals↗

Non-destructive detection of methionine sulfoxide in the resilium of a surf clam by solid-state 13C-NMR spectroscopy.

Methionine sulfoxide was detected in the resilium (internal hinge ligament) of a surf clam by high-resolution solid-state 13C-NMR spectroscopy involving cross-polarization and magic angle spinning, using no chemical procedure. The results support the previous report [Kikuchi, Y. and Tamiya, N. (1981) J. Biochem. (Tokyo) 89, 1975-1976] on a high content of methionine sulfoxide observed by chemical methods in the resilium protein of surf clam species.

Amino Acids↗

Pharmacokinetics of cefotetan (YM09330) in humans.

The pharmacokinetics and safety of cefotetan (YM09330) were examined after intravenous administration of single and multiple doses to normal volunteers. Cefotetan was well tolerated in single doses of 500 to 3,000 mg and in multiple doses of 500 and 1,000 mg at 12-h intervals for 1 and 3 days. These doses produced high plasma levels. The half-life (3 h) of cefotetan was longer than that of cefazolin. There was no evidence of drug accumulation in the plasma in the multiple-dose study. Mean recoveries of cefotetan in urine within a 24-h period were 74.5 to 88.4% of the dose, regardless of the route of administration and the dosage. The tautomer of cefotetan accounted for approximately 5% of the dose excreted in the urine. No tautomer was detected in plasma. Concentrations of drug in plasma and urine measured by microbiological assay were in good agreement with those measured by high-pressure liquid chromatography.

Adult↗

Force-velocity relationship of expiratory muscles in normal subjects.

We examined the force-velocity relationship of the respiratory muscles in normal subjects under nearly isotonic conditions, taking into consideration the pleural pressure (Ppl) changes during maximum forced expirations (MFE). We used an electromagnetic valve (EMV) to select the Ppl value at the onset of mouth flow; and both a pressure reservoir and a variable resistance to control the Ppl changes after the opening of the EMV during MFE. To simulate isotonic conditions and to obtain the shortening velocity of the contractile element (CE), we mathematically corrected the velocity of the series elastic component (SEC), using a modified version of Hill's equation. Although the maximum tension at total lung capacity (TLC) [1,156 +/- 215 (SD) g/cm] was larger than that at functional residual capacity (FRC) (782 +/- 97 g/cm) there was no significant difference in the maximum shortening velocity, 3.4 +/- 1.0 and 3.2 +/- 0.8 circumference/s at TLC and FRC, respectively. The mean values of k (slope) for the SEC at TLC and FRC were 19 +/- 4 and 18 +/- 5 circumference-1, respectively, and they were not significantly different. We concluded that the force-velocity relationship of the expiratory muscles exhibited the same mechanical properties as that of the other skeletal muscles.

Adult↗

Red blood cell deformability in renal failure.

Red blood cell deformability was measured in 74 cases of renal failure and diabetic nephropathy by means of a modified nuclepore membrane filter method. Low red blood cell deformability was observed in a certain proportion of the patients. In cases of renal failure only weak correlation was found between reduced red blood cell deformability and BUN as well as between reduced red blood cell deformability and creatinine level, while simultaneous changes in these variable were observed in several patients. The reduction in red blood cell deformability in cases of diabetic nephropathy slightly exceeded that in cases of renal failure and correlated with an increment in HbA1c content. The effects of uremic toxins were unclear in in vitro tests. The red blood cell deformability was impaired in nephrectomized rabbits.

Animals↗

A study of the deformability of red blood cells of a teleost fish, the yellowtail (Seriola quinqueradiata), and a comparison with human erythrocytes.

The blood of a carangid fish, the yellowtail (Seriola quinqueradiata) has been studied with particular reference to the deformability properties of the red blood cells. The rate at which blood flows through a Nuclepore filter containing 5 micrometers pores has been determined under the same conditions that have been used with human blood. Marked differences were found in the flow of yellowtail blood which depended on the particular way in which the blood had been sampled. Such differences seem to be due to a sensitivity of fish red blood cells to their environmental conditions. Blood flow through filters is temperature-dependent, the rate increasing with a rise in temperature. Measurements made at 37 degrees C gave values which were similar to those normally obtained for human red blood cells, in spite of their greater dimensions (10.4 x 6.8 x 3.4 micrometers), and nucleated nature. It was also found that the blood flow rate of human blood was slower than that of yellowtail blood when measured at the normal environmental temperatures (15 degrees C) for these fish.

Animals↗

Multiple atherosclerotic coronary aneurysms in association with acute myocardial infarction.

A 60-year-old woman with multiple coronary aneurysms, complicated with acute infero-posterior myocardial infarction is presented. The cine-coronary arteriogram disclosed a diffuse dilatation of epicardial coronary arteries associated with multiple aneurysms, fusiform ones in the right coronary and the left circumflex coronary arteries and saccular ones in the left anterior descending coronary artery. Distal run-off was poor. Ventriculography revealed a decrease in the ejection fraction (36%) and segmental abnormal wall motion at the apical and infero-posterior regions. The cause of the aneurysms appeared to be atherosclerotic. We suggested that coronary embolization was the cause of acute myocardial infarction in this case.

Aneurysm↗

Ultrastructural changes in the endothelial surface of the canine carotid artery induced by wall shear stress load.

To study the morphological changes in the endothelial surface of the artery induced by wall shear stress load, an arterio-venous shunt was constructed between the common carotid artery and the external jugular vein in 21 dogs. The ultrastructural changes in the endothelial surface were observed by scanning electron microscopy after the measurement of the hemodynamic parameters. In acute experiments (3 days or 1 week postoperative), the clear ultrastructural changes, such as the disturbance of the smooth folds, the find transverse wrinkles, the small spindle swellings, the splitting of the intercellular junction of the endothelial cells and occasionally the desquamation of the endothelial cells, were significantly observed as proportional to the elevated flow rate ratio (fs/fc, fs: flow rate of the shunted artery, fc: flow rate of the control artery). In subacute experiments (2 or 4 weeks postoperative), the small spindle swellings were observed in the shunted artery with high flow rate ratio. In chronic experiments (5 or 6 months postoperative), these changes were less proportional to the flow rate ratio. These morphological changes were significant in the disturbance of the endothelial barrier in acute experiments and they were significant in adaptive regulatory change in the chronic experiments. These support our previous observation (Am. J. Physiol. 239, H14-21, 1980). The possibility of the wall shear stress for atherogenesis was discussed.

Animals↗

White blood cell adhesion to endothelium and rheological behavior in microvessels of overinflated frog's lung.

The flow behaviors of white blood cells (WBCs) in frog's pulmonary microvessels were recorded and analyzed by means of a microscope-TV camera system. When the flow velocity in arterioles was reduced to a level lower than 1 mm/sec by a moderate overinflation of the exposed lung, WBCs rolled on the endothelial surface, frequently came in contact with the capillary orifice and passed it quickly without deformation. The time length which was required for WBCs to pass through the capillary orifice was shorter than the time length for red blood cells. This observation suggested that WBCs were no hinderance to blood delivery from arterioles to the capillary network in the normal and moderate overinflation of the lung. However, when the lung was strongly overinflated and the center line flow velocity was reduced to 0.1 mm/sec, WBCs adhered to the endothelium in ten minutes. The adhering WBCs could not be detached by the recovery of the blood flow. It seemed probable that a large shear stress up to 100 to 200 dynes/cm2 was necessary to pull down the interaction between the adhering WBCs and the endothelium.

Animals↗

Reduced red cell filtrability due to red cell plasma protein interactions.

The adsorption of protein on red cell surface was studied by the measurement of protein in plasma and incubation of blood with 131I-albumin. The protein concentration of the moderately hypertonic plasma clearly decreased by the addition of red cells. The decay counts of 131I-albumin increased in the centrifuged red cell segment as the ionic strength in the plasma increased. For the interpretation of these results it was assumed that the human red cells suspended in plasma are covered with albumin under the normal ionic strength and adsorb more albumin molecules when the ionic strength in the plasma is elevated by the addition of NaCl. A multilayer adsorption of albumin is suggested at the ionic strength of 450 mOsmol. The excess adsorption of albumin on red cells reduces the filtrability of red cells through the nuclepore filter.

Adsorption↗