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K Yashiro

Publications and source records attributed to K Yashiro.

At least 91 records · Page 5Linked to original sources

Comparison of phospholipid synthesis in rat salivary glands: properties of 1-acylglycerophosphorylcholine and 1-acylglycerophosphate acyltransferase systems in microsomes.

1. 1-Acyl-sn-glycerol-3-phosphorylcholine and 1-acyl-sn-glycerol-3-phosphate acyltransferase activities were characterized in rat salivary gland microsomes. 2. The acyl-CoA selectivities between these two kinds of lysophospholipid acyltransferase activities were very different. 3. When the three major glands were compared (parotid, submandibular, sublingual), they showed their own particular acyltransferase activity, but they had very similar in acyl-CoA selectivity. 4. Those observations were also compared in rat liver microsomes.

1-Acylglycerol-3-Phosphate O-Acyltransferase↗

Crohn's disease in the esophagus--report of a case.

A case of esophageal Crohn's disease is described. Crohn's lesion was observed in the lower esophagus, and sarcoid-like granulomas were found in the biopsied specimen. A clinical consideration of this phenomenon is presented.

Adult↗

Inducing effects of chronic administration of isoproterenol on 1-acyl-sn-glycero-3-phosphate and 1-acyl-sn-glycero-3-phosphocholine acyltransferases in rat parotid salivary gland.

1. In rat parotid gland, chronic administration of isoproterenol caused significant increase of linoleic acid and decrease of arachidonic acid at the sn-2 position of phosphatidylcholine. 2. The activities of 1-acyl-sn-glycero-3-phosphate and 1-acyl-sn-glycero-3-phosphocholine acyltransferases were increased 3-8-fold and 2-fold, respectively, in the parotid gland microsomes of isoproterenol-treated rat. 3. Furthermore, the specificity of these two enzymes for various acyl-CoAs was also changed by administration of isoproterenol. 4. The alteration of unsaturated fatty acid composition at the sn-2 position of phosphatidylcholine was at least in part due to the change of activity and substrate specificity of lysophospholipid acyltransferases.

1-Acylglycerol-3-Phosphate O-Acyltransferase↗

Alteration of membrane phospholipids in hypertrophied rat salivary glands induced by chronic administration of isoproterenol.

Hypertrophy of parotid and submandibular glands, and elevated phospholipid content per gland in both were induced. However, phospholipid content per tissue weight increased only in the parotid gland. Sublingual gland phospholipids were unaffected with regard to the gland weight and phospholipid content; phospholipid class compositions were altered in each of the three glands, typically an increase of phosphatidylcholine and decreases of sphingomyelin and phosphatidic acid. Concerning fatty-acyl groups in phospholipid, prominent increase of octadecadienoic acid was observed in total and individual phospholipids of both parotid and submandibular glands. However, eicosatetraenoic acid decreased in the total phospholipids of these two glands. In the sublingual gland, phospholipids, fatty-acyl compositions were not changed by isoproterenol. The results suggest that isoproterenol-induced changes of membrane phospholipids are regulated by at least two different effects, one for fatty-acyl groups and another for base moieties of phospholipids.

Animals↗

Comparison of membrane phospholipid and its fatty acid compositions in developing rat salivary glands.

1. Membrane phospholipid and its fatty acid compositions have been analyzed in 3- and 9-week-old rat salivary glands. 2. When compared between the three major glands (parotid, submandibular, sublingual) in adult rats, phospholipid compositions were similar, but for their fatty acid, characteristic properties from each phospholipid were shown. 3. Alterations in their compositions were also observed during development of the salivary glands.

Aging↗

Properties of membrane phospholipids and their fatty acyl compositions of secretory granules from rat parotid gland.

A secretory granular fraction isolated from rat parotid glands was remarkably different from a microsomal fraction in its phospholipid composition. It had higher levels of lysophospholipids (8%) and phosphatidylethanolamine (31%), while there were lower levels of phosphatidylcholine (40%) and phosphatidylserine (2.1%) than the microsomal fraction. However, fatty acid compositions of individual phospholipid classes from the two subfractions were found to be nearly similar to each other. ESR analysis demonstrated that extracted phospholipids from the secretory granular fraction were more fluid than those from microsomes. The relevance of these observations to physiological function of secretory granules is discussed.

Acid Phosphatase↗

Two-dimensional Doppler echocardiographic assessment of closure of the ductus arteriosus in normal newborn infants.

To elucidate the mechanism involved in closure of the ductus arteriosus (DA), 50 normal full-term infants were examined with two-dimensional and pulsed Doppler echocardiography. The examinations were performed initially within 1 hour after delivery and serially for 3 days. The two-dimensionally derived long-axis plane of the DA disclosed a characteristic localized protrusion into its lumen in 30% of the subjects within 1 hour, in 80% by 4 hours, in 96% by 8 hours, and in all by 24 hours after birth. In 10 infants in whom the intraluminal protrusion did not appear within 4 hours after birth, none had any recognizable changes in the inner diameter or length of the DA during this initial period. The development of the intraluminal protrusion resulted in localized narrowing of the ductal lumen. Doppler echocardiography revealed a high-velocity jet within and downstream from the narrowed portion of the DA. Thereafter, ductal narrowing progressed along the entire length. The intraluminal protrusion may be early evidence of ductal changes leading to eventual functional and anatomic closure.

Age Factors↗

Noninvasive Doppler echocardiographic evaluation of shunt flow dynamics of the ductus arteriosus.

The pulsed Doppler technique was used to record the flow velocity patterns in the ductus arteriosus and the pulmonary artery in 26 patients with either isolated or complicated patent ductus arteriosus (PDA). In all patients, abnormal Doppler signals indicating left-to-right (L-R) or right-to-left shunt flow or both could be obtained at the site of the ductus arteriosus. These Doppler flow patterns determined within the ductus coincided with the direction of ductal flow seen on the contrast two-dimensional echocardiogram. No Doppler signals of shunt flow were demonstrated in any of 42 control subjects. The peak, mean, and diastolic velocities of the L-R shunt flow within the ductus were measured from the ductal flow velocity profiles. With the Doppler-derived measurements of the mean and diastolic velocities, patients with normal pulmonary arterial pressure and those with evidence of pulmonary hypertension could be correctly identified. In addition, the mean velocity of the diastolic antegrade flow portion obtained from the proximal left pulmonary artery, which was related to ductal L-R shunting, was measured in 16 patients with isolated PDA. This Doppler flow determinant showed a good linear correlation with the L-R shunt ratio determined by Fick's method (r = .88, p less than .01). Our technique permits the noninvasive evaluation of shunt flow dynamics in patients with PDA.

Blood Flow Velocity↗

Characterization of pulmonary carbonyl reductase of mouse and guinea pig.

Carbonyl reductases were purified from mouse and guinea pig lung. The mouse enzyme exhibited structural and catalytic similarity to the guinea pig enzyme: tetrameric structure consisting of an identical 23 kDa subunit; basicity (pI of 8.8); low substrate specificity for aliphatic and aromatic carbonyl compounds; dual cofactor specificity for NADPH and NADH; stereospecific transfer of the 4-pro S hydrogen of NADPH; and sensitivity to pyrazole, 2-mercaptoethanol and ferrous ion. Although 3-ketosteroids were extensively reduced by the mouse enzyme but not by the guinea pig enzyme in the forward reaction, the two enzymes similarly oxidized some alicyclic alcohols such as acenaphthenol, cyclohex-2-en-1-ol and benzenedihydrodiol in the presence of NADP+ and NAD+. A partial similarity between the two enzymes was observed immunologically, using antibodies against the purified guinea pig enzyme. The lung enzymes differ in several aspects from other oxidoreductases from extrapulmonary tissues. The immunoreactive protein was detected only in lung of the tissues of the two species.

Alcohol Oxidoreductases↗

Esophageal lesions in intestinal Behçet's disease.

Esophageal lesions are rarely seen in patients with intestinal Behçet's disease. Three patients with esophageal lesions (dissection of esophageal mucosa, esophageal ulcer, esophageal varices) were observed among 15 patients with intestinal Behçet's disease or non-specific simple ulcer (1974-1984). Two-thirds of these fifteen patients had fully developed or suspected Behçet's disease, and one-third had no symptoms typical of Behçet's disease. They are classified as non-specific simple ulcer. The average age of the 15 patients was 43 years, all patients but one were male. The recurrence rate after surgical treatment was 70%, that of medical treatment was 90%.

Adult↗