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Biomedical subjects

T Yoshimura

Publications and source records attributed to T Yoshimura.

At least 721 records · Page 40Linked to original sources

[Some properties of a vasopressor substance generated in human plasma by incubation and its clinical significance in pregnancy-induced hypertension].

A study to measure the pressor substance, called active pressor principle (APP), which is generated in incubated human plasma was performed using anesthetized and ganglion blocked rats. It was found that APP has properties characteristic of protein. APP was not extractable with mixtures of chloroform: methanol. APP was present at 50 to 70% saturation with ammonium sulfate. By treating the plasma with Pronase, the pressor activity of the plasma was almost completely abolished. The molecular weight of APP as determined by gel filtration was about 68,000. By adding diisopropyl fluorophosphate before incubation of the plasma, the generation of vasopressor substance was prevented. Treatment of the rat with captopril was ineffective in inhibiting the pressor effect of incubated plasma. It was found that the plasma of normal pregnant women generated significantly higher amounts of APP than the plasma of nonpregnant women. The plasma obtained from patients with pregnancy-induced hypertension generated significantly lower amounts of APP than the plasma of normal pregnant women. These findings suggest that a vasoactive protein (APP) is generated during simple incubation of plasma, and a serine protease is involved in the formation of this substance. Concerning the relevance of these results to blood pressure regulation in pregnancy-induced hypertension, probably APP is involved in blood pressure regulation via a compensatory mechanism.

Female↗

Endometriosis associated with ascites.

Pelvic endometriosis associated with massive ascites is an unusual occurrence. Only 12 cases have been reported since 1954 when Brews first described this entity. The authors present two cases recently encountered at Saga Medical School Hospital. Clinical courses and operative findings are described and other cases from the literature are reviewed. The possible etiologic mechanisms of the ascites are explored and the possibility of conservative surgery and hormonal therapy with danazol is discussed.

Adult↗

[Establishment and characterization of a cell line derived from mucinous cystadenocarcinoma of human ovary].

A human tumor cell line MCAS, which was derived from mucinous cystadenocarcinoma of the ovary, was established. The tissue specimen was obtained on December 1, 1983 and the culture was maintained in Ham's F-12 medium supplemented with 20% fetal calf serum. Continuous growth made possible cell transfer every 3-5 days and the seventy-third passage was achieved on August 15, 1984. This cell line has the following characteristics. The doubling time of the MCAS cell line was 27 hours and the saturation density was 5.1 X 10(4)/cm2. The cultured cells appeared monolayer and the cellular arrangement was a pavement-like pattern. Rather large cells with vacuoles in the cytoplasm appeared in the confluent state and PAS staining proved to be positive specifically in these large cells. A chromosomal analysis revealed a peritetraploid tendency. By heterotransplantation of MCAS cells to the nude athymic mouse, the tumor developed and had both cystic and solid components. The cystic content was mucinous. Histopathological diagnosis of the tumor was papillary adenocarcinoma and alcian blue staining was positive. The characteristics of the original mucinous cystadenocarcinoma have been precisely maintained in this cell line.

Animals↗

Partition of amphiphilic molecules into phospholipid vesicles and human erythrocyte ghosts: measurements by ultraviolet difference spectroscopy.

Molar partition coefficients for chlorpromazine and methochlorpromazine between phospholipid vesicles or human erythrocyte ghosts and buffer are determined by ultraviolet difference spectroscopy. The partition coefficients between small unilamellar egg phosphatidylcholine vesicles and buffer at pH 7.4 are 4.4 X 10(5) for chlorpromazine and 0.8 X 10(5) for methochlorpromazine, determined with 10 microM amphiphile. An increase in the partition of chlorpromazine into vesicles is seen as the pH is increased to the pKa of chlorpromazine at 9.2. Chlorpromazine also partitions preferentially into fluid-phase phospholipid compared to solid-phase phospholipid. Molar partition coefficients between unsealed human erythrocyte ghosts and buffer at pH 8.0 with 10 microM amphiphile are determined to be 6.5 X 10(5) for chlorpromazine and 2.5 X 10(5) for methochlorpromazine. Difference spectroscopy is an equilibrium technique that does not require separation of bound from free amphiphile, as do many other methods of determining membrane-buffer partition coefficients. This method is useful for any amphiphile that has an appreciable absorbance below its critical micelle concentration and whose absorbance is sensitive to environment.

Chemical Phenomena↗

[Review on dietary methods for epidemiologic studies].

Different dietary methods have been used for epidemiologic studies on nutrition, diet and disease. Methods so far reported are classified into dietary record method (including weighing method), recall method, Burke's method, frequency method, and semiquantitative frequency method. The recall method and frequency method are considered to be unsuitable when the average intake of nutrients and foods of individuals is to be assessed. It is difficult for a person to recall food intake over several days, and the 24-hour recall method is unable to evaluate the average intake. Quantitative assessment of intake is hardly possible in the frequency method. Dietary evaluation in case-control studies has limitations in terms of difficulties in retrospective dietary assessment and the change in dietary habit over a long period of time. Current epidemiologic knowledge on diet and disease stimulates cohort studies using the 7-day dietary record or semiquantitive frequency method.

Diet Surveys↗

Bovine brain phosphatidylinositol transfer protein. Effects of pH, ionic strength and lipid composition on transfer activity.

Phosphatidylinositol and phosphatidylcholine are transferred between bilayer membranes in the presence of a specific phosphatidylinositol transfer protein isolated from bovine brain. The effects of pH, ionic strength and lipid composition on the rate of transfer of these phospholipids between small unilamellar vesicles have been investigated. At low ionic strength, phosphatidylinositol transfer between vesicles prepared from phosphatidylcholine and 5 mol% phosphatidylinositol was maximal at about pH 5 and moderately dependent on hydrogen ion concentration in more alkaline regions. A similar dependence on pH was noted for phosphatidylcholine transfer between membranes containing phosphatidylcholine or mixtures of phosphatidylcholine and 5 mol% phosphatidylinositol, phosphatidic acid, phosphatidylglycerol, phosphatidylethanolamine or stearylamine. The rate of transfer between anionic vesicles was somewhat higher than that between neutral or cationic vesicles. At higher ionic strength the transfer reactions in neutral and alkaline regions were less sensitive to pH. Phospholipid transfers between vesicles containing 5 mol% of anionic lipid increased sharply as ionic strength decreased below 0.1. In contrast, phosphatidylcholine transfer between membranes which contained only zwitterionic phospholipids or 5 mol% stearylamine was unaffected by variations of ionic strength. Irrespective of the lipid composition of membranes, pH affected both the apparent Km and Vmax, while ionic strength generally affected the apparent Vmax. These results indicate a significant role of electrostatic interactions in the phospholipid transfer catalyzed by phosphatidylinositol transfer protein.

Animals↗

Imidazole, imidazolate, and hydroxide complexes of (protoporphyrin IX)iron(III) and its dimethyl ester as model systems for ferric hemoproteins: electron paramagnetic resonance and electronic spectral study.

The EPR and electronic spectral changes upon titration of systems consisting of (protoporphyrin IX)iron(III) chloride (Fe(PPIX)Cl) or its dimethyl ester (Fe-(PPIXDME)Cl) and imidazole derivatives with tetrabutylammonium hydroxide solution have been measured at 77 and 298 degrees K in various solvents. The EPR and electronic spectra of the melt of Fe(PPIXDME)Cl in imidazole derivatives have been also measured. The imidazole derivatives studied here were imidazole and 4-methyl-, 4-phenyl-, 2-methyl-, 2,4-dimethyl-, 1-methyl-, and 1-acetylimidazole. The spectral changes upon addition of hydroxide were markedly different between the systems containing NH imidazoles (BH), with a dissociable proton, and those containing NR imidazoles (BR), without it. In the former systems, five spectral species were successively formed at 77 degrees K and were assigned to following complexes: [Fe(P)(BH)2]+, Fe(P)(BH)(B), [Fe(P)(B)2]-, Fe(P)(BH)(OH), and [Fe(P)(B)(OH)]-, where P is PPIX or PPIXDME. In the latter systems, initial complex, [Fe(P)(BR)2]+, was found to be changed to final complex, Fe(P)(BR)(OH), through an intermediate at 77 degrees K. At 298 degrees K, both systems were found to react with hydroxide to finally form Fe(P)(OH). The crystal field parameters were evaluated using the EPR g values in low-spin complexes studied here and in hemoproteins. The five regions corresponding to five low-spin complexes could be distinguished in crystal field diagrams.

Chemical Phenomena↗

Electronic spectra for nitrosyl(protoporphyrin IX dimethyl ester)iron(II) and its complexes with nitrogenous bases as model systems for nitrosylhemoproteins.

Soret and visible absorption spectra for nitrosyl(protoporphyrin IX dimethyl ester)iron(II) (Fe(PPIXDME)(NO] and its complexes with nitrogenous bases (imidazoles, pyridines, aliphatic amines, and cyclic secondary amines) as model systems for nitrosylhemoproteins have been measured in various solvents. As the solvent polarity increases, the Soret and visible absorption bands for the five-coordinate Fe(PPIXDME) (NO) were shifted to shorter wavelengths. Accompanying the coordination of a nitrogenous base to the vacant axial position of Fe(PPIXDME)(NO), the Soret band becomes sharp and the band maximum is shifted to longer wavelengths. The band positions for the six-coordinate Fe(PPIXDME)(NO)(Base) complex are not sensitive to the pi-bonding ability of the axial ligand trans to NO group. The electronic spectra of five-coordinate Fe(PPIXDME)(NO) and six-coordinate Fe(PPIXDME)(NO)(Base) complexes are interpreted in relation to the structural information. The comparison of the spectra for model systems with those for nitrosylhemoproteins is discussed.

Amines↗

Growth hormone studies in lysinuric protein intolerance.

Our two patients with lysinuric protein intolerance, a 14-year-old boy and his 12-year-old sister, showed growth retardation and their bone ages were retarded. Growth hormone secretion responded to glucagon-propranolol and showed a good response to arginine. However, growth hormone showed little response to insulin. After the oral administration of arginine hydrochloride, growth hormone showed a good response to insulin and glucagon-propranolol, and gain in height and weight accelerated. This result may suggest that an adequate supply of arginine is effective in improving the growth retardation in lysinuric protein intolerance.

Adolescent↗

Chemotactic subpopulation of macrophage cell line cells (M1 cells) discerned by three macrophage chemotactic factors from delayed hypersensitivity reaction sites.

The functional specificity of three types of macrophage chemotactic factors ( MCFs ), -a, -b, and -c, from purified protein derivative of tuberculin (PPD)-induced delayed hypersensitivity reaction (DHR) skin sites on guinea pigs, was analyzed using macrophage cell line cells, M1, established from myeloid leukemia cells of a SL/Am strain mouse. M1 cells yielded two subclones: Mk1 cells, which were Ia+ and migrated specifically toward MCF-c; and Mm1 cells, which were Ia- and migrated specifically toward MCF-a and -b. These differences show the heterogeneity of the biologic activities of the MCFs in the presence of cell line cells. M-1 cells, blast cells, when grown in continuous culture, migrated toward none of the MCFs . Upon differentiation to mature macrophage-like cells in conditioned medium (M+1 cells), however, they migrated to MCF-a, -b, and -c and the experimental evidence points to the possibility that M+1 cells are separated into subpopulations on the basis of their chemotactic response. Cytotoxic treatment of M+1 cells with anti-Ia antisera resulted in the specific decrease of activity toward MCF-c. Furthermore, MCF-c attracted Ia-positive M+1 cells, while MCF-a and -b attracted Ia-negative M+1 cells. Thus, our results indicate the existence of two migrating subpopulations of M+1 cells with specificities for MCF-a, and -b and for MCF-c, respectively. The data suggest that MCF-c attracts Ia-bearing accessory macrophages and MCF-a and -b attract Ia-negative macrophages in the DHR.

Animals↗

The effect of carboxylates and halides on L-lysine 6-aminotransferase-catalyzed reactions.

L-Lysine:2-oxoglutarate 6-aminotransferase catalyzes very slow transamination between L-alanine and 2-oxoglutarate. A high concentration of anions such as formate, acetate and halides greatly accelerated this transamination without affecting the affinity of the enzyme for L-alanine. In contrast, the anions strongly inhibited the normal L-lysine 6-transamination in a competitive manner with L-lysine and in a non-competitive manner with 2-oxoglutarate. This result suggests that the enzyme has an anion binding site which normally binds the carboxyl group of L-lysine. The binding of halides or carboxylates to this site probably induces a conformational change of the enzyme, and results in the inhibition of L-lysine 6-transamination, and in the stimulation of L-alanine transamination. Treatment of the enzyme with an arginine-specific dicarbonyl reagent, phenylglyoxal, led to a loss of the enzyme activity for L-lysine. The activity for L-alanine was not affected, but the stimulating effect of anions on L-alanine transamination was impaired. Thus, it is suggested that an arginine residue(s) plays an important role in the anion binding site.

Alanine↗

Cytogenetic and functional studies of leukocytes with Pelger-Huët anomaly.

A cytogenetic study was undertaken in 15 cases of Pelger-Huët (P-H) anomaly in 3 families. An enlarged short arm of chromosome 22 (22p+) was found in 14 cases, but in these families 4 cases without P-H anomaly did not show 22p+ in the karyotype. In P-H anomaly, delayed skin hypersensitivity reactions, levels of serum IgG, IgM and IgA, lymphocyte subpopulations, and natural killer and antibody-dependent, cell-mediated cytotoxicity activities were within normal range. The level of serum IgE, mitogen responses in peripheral blood lymphocyte and plaque-forming cell counts were also within normal range with the exception of a case with atopic eczema. Enzymatic activities, nitroblue tetrazolium reduction and phagocytic capacities of neutrophils appeared normal. Abnormalities of neutrophils in cases of P-H anomaly, as compared with normal subjects, were also negative in examinations for chemotaxis and spontaneous migration under agarose and in a membrane filter.

Adolescent↗

Surgical implications of the pathophysiology of advanced valvular heart disease.

The pathophysiology of advanced valvular heart disease and its clinical implications were analyzed. The study was undertaken primarily on 153 recent patients with implantation of central flow valves. The operative mortality rate was 3.9%, with deaths except one related to LOS. There was a higher incidence of LOS in left ventricular volume-overloaded hearts, and a much higher incidence in patients associated with TR: 70% of TR cases with RVEDP higher than 15 mmHg developed LOS. Cardiac contractile reserve proved to be useful index for predicting immediate postoperative and long-term results; less favorable results were indicated in patients with PWE below 10 mm even after epinephrine infusion. In volume-overloaded hearts, the muscle cell diameter of the left ventricle increased proportionally to the dimension of the left ventricle, with interstitial fibrosis representing irreversible morphological change. Patients with a prolonged indocyanine green disappearance rate showed fibrosis of the liver and were complicated more frequently by LOS, hepatic and renal disturbance and increased mortality. Patients with cardiac cachexia were liable to develop LOS postoperatively, and preoperative GIK therapy appeared to be effective in improving depressed metabolism and hemodynamics, except in patients with severe TR.

Adult↗