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Y Yoshino

Publications and source records attributed to Y Yoshino.

At least 19 recordsLinked to original sources
PubMed1992

Soybean protein isolate and soybean lectin inhibit iron absorption in rats.

Inhibitory effects of soybean protein isolate (SPI) and soybean lectin on the intestinal absorption of nonheme iron were investigated by in vivo studies in rats. Rats fed the SPI-based diet absorbed significantly less iron than did control rats fed the casein-based diet. Supplementing the SPI diets with 8% D-galactose significantly increased the incorporation of iron into liver ferritin, although D-galactose did not significantly increase iron absorption. Heat treatment of SPI significantly increased iron absorption. Ascorbate did not enhance iron absorption in rats fed the SPI-based diet. The presence of lectin in an aqueous extract of SPI was suggested by hemagglutination activity as well as by immunoreactivity with soybean lectin antibody. Soybean lectin introduced into ligated segments of the upper small intestine of rats inhibited ferrous iron absorption. This inhibitory effect, especially in the mucosal uptake, was significantly improved by addition of N-acetyl-D-galactosamine to soybean lectin. Soybean lectin had no effect on ferric iron absorption. Our results suggest that a portion of the reduction in iron absorption in rats fed SPI may be due to lectins.

Animals↗
PubMed1992

Primary angiosarcoma of the right atrium detected by magnetic resonance imaging.

A 20-year-old woman with a primary angiosarcoma of the right atrium is reported. The patient had a cardiorespiratory arrest due to cardiac tamponade with bloody pericardial effusion. Magnetic resonance imaging (MRI) revealed a tumor, which was corroborated by selective coronary angiography. Open-heart surgery was performed. The tumor relapsed however, and she died four months after operation. The tumor was undetectable by echocardiography, but MRI demonstrated a heterogeneous mass with focal areas of high- and low-signal intensity in the right atrium, suggesting that MRI may allow characterization of cardiac tumors.

Adult↗
PubMed1991

Effects of iron on lipid peroxidation.

To elucidate the effects of iron on lipid peroxidation, three kinds of assays were done. (i) The effects of intravenous injection of single doses of iron dextran (100 mg iron) on lipid peroxidation in various tissues and the blood plasma of rats were examined by the thiobarbituric acid reaction. Malondialdehyde concentrations were significantly elevated in the spleen, heart, and plasma 3 h after injection, whereas significant increases were observed in the liver and adipose tissue at 24 and 48 h, respectively. In the liver and spleen, the elevated malondialdehyde concentrations persisted until Day 28. In contrast, levels were reduced in the heart and adipose tissue within 4 weeks after iron injection. Plasma malondialdehyde concentrations were 70-times that of controls at 24 h after iron injection. The level subsequently decreased sharply by Day 6. In red blood cells, lipid peroxidation was not affected by iron. Malondialdehyde levels were correlated with the iron contents of the liver, spleen, heart, adipose tissue, and plasma (r value range 0.39-0.88, p less than 0.05). Furthermore, there was a strong correlation in the liver and spleen at iron levels below 2,000 micrograms/g (r = 0.94, p less than 0.0001; r = 0.94, p less than 0.0001, respectively). (ii) In vitro experiments demonstrated that the addition of iron as ferric chloride, iron dextran, ferritin, and hemosiderin to normal liver homogenate accelerated malondialdehyde production. However, such increases were less than 10% of those caused by equivalent iron in the liver homogenate of iron treated rats. (iii) Compared to controls, spleens from eight thalassemia patients showed a high level of malondialdehyde and iron.

Adipose Tissue↗
PubMed1991

The role of diferric transferrin in iron absorption and transferrin concentration in rat pancreatic juice and milk.

Transferrin (Tf) was found immunologically in pancreatic juice of normal rats at a concentration of 0.28 +/- 0.10 mg/ml but was found to be approximately 4-times higher in iron-deficient rats. Iron saturation of pancreatic Tf of normal rats was 40% and similar to that of serum Tf. Approximately 27% of a dose of iron from 59Fe-diferric Tf was absorbed through the ligated segments of proximal intestine in normal rats. The iron absorption ratio of 59Fe-diferric Tf was higher from the duodenal and jejunal segments than the ileum and significantly inhibited by monodansylcadaverine (MDC) or 20-times excess of unlabeled diferric Tf. The presence of Tf receptors was demonstrated by specific binding of 125I-diferric Tf to the brush border membrane vesicles of the small intestine in normal rats. The binding was not inhibited by the presence of albumin or IgG. The association constant (Ka) was 1.03 +/- 0.50 x 10(8) M-1 and number of binding sites was 5.10 +/- 0.96 x 10(12) sites/mg protein in the proximal intestine. The number of binding sites for Tf was higher in the proximal intestine than in the distal one. These results suggested that some iron was absorbed as diferric Tf into enterocytes through receptor-mediated endocytosis.

Animals↗
PubMed1991

[A case of measles meningoencephalitis with marked increase of plasma cells in cerebrospinal fluid].

Marked increase of plasma cells in cerebrospinal fluid (CSF) was observed in a 22-year-old female patient with measles meningoencephalitis. Typical measles exanthema was followed, 3 days later, by neurological abnormalities such as confusion, severe meningeal signs and bilateral pyramidal signs. Immunological examination showed slight elevation of IgG, normal T cell subsets and NK cell activity in peripheral blood. The antibody titer of measles was 32x in serum (4x after 2 months). CSF contained 167 cells/mm3, 66% of which was plasma cells. Total protein was 75 mg/dl, and IgG (24.5 mg/dl) showed high values. The antibody titer of measles was 4x (1x after 2 months). The antibody index was 7.15 (N = 2). The anti-myelin antibody was 8x. Oligoclonal band in CSF was negative. The appearance of large number of plasma cells in CSF in viral meningoencephalitis is extremely rare in the literature. However, B cell activation in peripheral blood in measles encephalitis has been reported. Therefore, immunologically abnormal findings in CSF of this case suggest marked B cell activation occurring in the central nervous system in measles meningoencephalitis.

Adult↗
PubMed1990

Utilization of vitamin A in rats with inflammation.

Reductions in the concentration of retinol (vitamin A) in serum, lung and kidney were observed in rats subjected to inflammation-inducing treatments (turpentine oil injection of thermal injury). At the same time, the liver showed an almost normal vitamin A content. Feeding of retinol to vitamin A-depleted rats with inflammation revealed that intestinal absorption of retinol was still active in the inflamed state, and the livers of these rats showed good incorporation of retinol. The livers of normal and vitamin A-depleted rats subjected to the inflammatory treatments showed a normal RBP content (retinol-binding protein) and hepatic release of holo-RBP into the serum was not impaired functionally. These results suggest the possibility that the decreases of vitamin A in the lung, serum and kidney may be due primarily to enhanced local consumption of vitamin A related to the inflammation, rather than to a reduced supply of vitamin A from the liver or to decreased intestinal absorption. In bovine serum albumin (BSA)-sensitized rats produced by direct intubation of BSA into the lungs, the level of vitamin A in the lung decreased prior to that in the liver or serum, supporting the hypothesis that the decrease in vitamin A in the inflamed lungs of these rats may be due mainly to the consumption of vitamin A in the lung in response to inflammation.

Animals↗
PubMed1990

Characteristics of activation of rat mast cells by polyethylenimines and a polyallylamine: effects on the release of histamine and of arachidonate and its metabolites.

1. Three polyethylenimines and one polyallylamine released radioactivity from rat peritoneal mast cells labeled with [1-14C]arachidonic acid and concomitantly released histamine from the cells. 2. This enhancement of the release of radioactivity was inhibited by phospholipase A2 inhibitors, quinacrine (1 mM) and p-bromophenacyl bromide (10 microM), suggesting that polyethylenimine and polyallylamine activates phospholipase A2 to generate arachidonate and its metabolites. 3. The effects of H-7 or K-252a, general kinase inhibitors for the release of histamine and of arachidonate and its metabolites induced by the polycations, were different from those of W-7, a calmodulin inhibitor. The mechanisms to generate arachidonate and its metabolites seemed to differ from those to release histamine; activation of phospholipase A2 by the polycations was calmodulin-dependent. 4. p-Bromophenacyl bromide inhibited the histamine release induced by polyethylenimines and a polyallylamine, suggesting that arachidonate production by means of phospholipase A2 activation by polycations is an important process in the release of histamine from mast cells.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗
PubMed1990

An analysis of subretinal fluid in bullous retinal detachment.

A patient with bilateral bullous retinal detachment underwent drainage of the subretinal fluid. The analysis of the subretinal fluid revealed a high protein concentration--17.4 g/dl OD, 27.5 g/dl OS--which was 3-5 times higher than that of the patient's serum. The protein fractionations of the subretinal fluid were almost the same as those of the serum. These findings may well explain the shifting fluid and support the theory that bullous retinal detachment is caused by the breakdown of retinal pigment epithelial function as a barrier between the choroid and retina.

Adult↗
PubMed1990

Advantage of cine-MR imaging for the evaluation of valvular regurgitation.

It is well known that the regurgitant blood flow of valvular disease shows a low intensity signal (LS) in cine-MR imaging (cMRI). To determine the significance of cMRI in evaluation of valvular regurgitation, 104 patients who had been assessed by cineangiography also underwent oblique cMRI for mitral regurgitation (MR) and aortic regurgitation (AR), and transverse cMRI for tricuspid regurgitation (TR). In evaluating the accuracy of diagnosis of valvular regurgitation on the basis of the presence of LS in the recipient chamber, sensitivity was found to be 93.5% for MR, 100% for AR and 85.7% for TR; specificity was 76.9% for MR and 100% for AR. The length and area of LS were planimetered in any view with the largest area, and its ratios to the length and area of the recipient chamber of view were calculated. Each index was significantly higher than the degree calculated by cineangiography. The best correlation with angiography was the ratio of the area of LS to the recipient chamber, and a semiquantitative classification by the index was coincident with angiographic severity in 38 of 43 (88.4%) patients undergoing MR, and in 28 of 30 (93.3%) patients undergoing AR. Thus, cMRI is a clinically useful noninvasive method in the identification and semiquantitative assessment of regurgitation severity.

Aortic Valve Insufficiency↗
PubMed1990

Comparison of histamine release induced by synthetic polycations with that by compound 48/80 from rat mast cells.

We compared the histamine release induced by polyethylenimines and polyallylamines with that induced by compound 48/80. Lidocaine inhibited the histamine release induced by polyethylenimine with a molecular weight of 600 (PEI6), but disodium cromoglycate did not. The histamine releases induced by all polyethylenimines and polyallylamines tested were inhibited by lidocaine, but not by disodium cromoglycate. Islet activating protein inhibited the histamine release induced by PEI6. Its effects on the release by other polyethylenimines and polyallylamines were less than that on PEI6. It is likely that the inhibition of G proteins by islet activating protein resulted in a decrease of the histamine release. This possibility was supported by the finding that guanyl-5'-(beta, gamma-imino) triphosphate enhanced the histamine release. An inhibitor of polyphosphoinositide phosphodiesterase, neomycin, did not affect the histamine releases induced by these polymers. The effect of PEI6 seemed to resemble that of compound 48/80. After pretreatment of mast cells with wheat germ agglutinin and with Limax flavus agglutinin, releases of histamine induced by PEI6 and compound 48/80 decreased, suggesting that the binding sites of PEI6 and compound 48/80 had sialic acid and/or N-acetyl glucosamine residues. The binding site for PEI6 seemed to especially overlap those of compound 48/80.

Animals↗
PubMed1990

Concentrations of lactoferrin and iron in human milk at different stages of lactation.

Lactoferrin (LF) was isolated from human milk by serial procedures of 45% ammonium sulfate precipitation, CM Sephadex C-50 ion-exchange chromatography, Sephadex G-100 gel filtration, and Cu-affinity chromatography, in which 59Fe lactoferrin was used as the tracer. The recovery of LF from human milk was 3.3%. LF from human milk was a single component having a molecular weight of 78k on SDS-PAGE, and showed pI 8.02 by isoelectric focusing on slab gel. The LF concentration was measured by rocket immunoelectrophoretic assay using anti-human LF antiserum in human colostrum and milk, from 1 to 60 days after parturition (125 samples). The LF concentrations in colostrum (1-3 days of puerperium, n = 35), the transitional milk (4-7 days, n = 60), and mature milk (20-60 days, n = 30) were 6.7 +/- 0.7, 3.7 +/- 0.1, and 2.6 +/- 0.4 (mean +/- SEM) g/liter, respectively. Both the LF and total protein (TP) concentrations showed significantly inverse correlations with the days after parturition (p less than 0.001). The lactoferrin/total protein ratio (LF/TP) in the mature milk (16.1 +/- 1.4%) was significantly less than that in the colostrum (20.4 +/- 1.2%, p less than 0.05) and the transitional milk (21.4 +/- 0.9%, p less than 0.05). Furthermore, iron concentration (Fe) in human milk was also measured by the internal standard technique of the spiked method on atomic absorption, and the lactoferrin iron saturation (LS%) was calculated. Neither Fe nor LS% had significant difference among these three stages of the lactation. The means (n = 125) of Fe and LS% were 60.6 +/- 5.4 micrograms/100 ml and 11.8 +/- 1.1%, respectively. However, significant correlation was observed between LF and Fe (p less than 0.005) or between LF/TP and both of Fe (p less than 0.05) and TP (p less than 0.001) in the mature milk. These results suggest that the mechanism stimulating the synthesis and secretion of LF is different from those of other proteins and LF can play variable roles in iron nutrition of babies at the different stages of lactation.

Amino Acids↗
PubMed1990

[Assay of nuclear triiodothyronine receptors in the precentral gyrus in patients with amyotrophic lateral sclerosis].

Abnormality in the receptor of the cell might have some bearing on the selective cellular damage in systemic degenerative diseases. In relation to deranged metabolic turnover of the folate cycle in amyotrophic lateral sclerosis (ALS), we have measured nuclear triiodothyronine receptors (NT3R) in the precentral gyrus, stored at -80 degrees C after autopsy, of 4 ALS patients and 8 patients with non-neurological diseases. Cell nuclei were separated in bulk from about 1 g of grey matter by the method of Løvtrup-Rein & McEwen, and T3-binding assay was carried out by the method of Silva et al. DNA was measured by the method of Giles & Myers based on Burton's method. Specific bindings comprised more than 85% of total bindings. Scatchard analysis showed that the maximal binding capacity, namely the density of NT3R was significantly reduced in ALS, compared to that of the controls. The dissociation constant, namely the affinity was not different between the two groups. The present investigation suggests that NT3R may be reduced in the motoneuron of ALS patients, although the result might merely indicate the loss of nerve cells from the ALS motor cortex. This point should be clarified, but the bulk separation of pure nerve cell nuclei from autopsied human brain has not so far been successful in our laboratory. Action of thyroid hormone in the mature brain has not fully been clarified. Meanwhile, some investigators suggest that the metabolic state of the central nervous system of ALS has a tendency of hypothyroidism. Therefore, the relevance of thyroid hormone to pathogenesis or pathophysiology of ALS will be an important subject in future study.

Aged↗
PubMed1990

[Polyesthesia--report of two cases].

Polyesthesia is an abnormal sensation in which a single sensory stimulation seems to be felt as several ones. We report two cases showing this rare phenomenon. The first case was a 34-year-old man having a history of SLE for 20 years. When he was 22 years old, he suffered from transverse myelopathy at the tenth thoracic level. Two years after this episode, he noticed a curious sensory experience. Namely, when he rubbed his hand or lateral trunk, similar sensation occurred on the foot of the same side simultaneously. This phenomenon has continued for ten years. The characteristics of this double sensation were as follows; effective modes of stimulation were rubbing, tapping and vibration. Pinprick or cold/warm stimuli could not elicit any sensation on the foot. The sensation observed on the foot was always ipsilateral and simultaneous in almost symmetrical distribution. Rubbing the foot could not elicit any sensation on the hand or trunk. Somatosensory evoked potentials (SEPs) following tibial and peroneal nerve stimulation could not be recorded on the scalp. Dermatomal SEPs below the tenth thoracic level were also silent over the scalp. SEPs obtained by median nerve stimulation were normal bilaterally. Various neuroradiological examinations including CT and MRI were noncontributory. This phenomenon, diagnosed as synesthesia, may be related to denervation supersensitivity after spinal cord lesion and sprouting from the fibers conveying hand and thoracic information to those denervated neurons at the posterior column nuclei. The second case was a 70-year-old woman having a history of syphilis. She noticed a characteristic sensation for ten years. Namely, when she rubbed her face, especially her forehead and cheeks, another sensation occurred 1 second after primary stimulation at the same place.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[Three cases of spontaneous rupture of the oesophagus (Boerhaave's syndrome)].

We reported three cases of spontaneous rupture which were surgically treated with direct suture method. One patient was operated on within eight hours after rupture with good results. In two patients diagnoses were made more than two days after rupture. One had esophageal fistula, but completely recovered after cervical oesophageal fistula, and another died of multiple organ failure. In this syndrome, early diagnosis and surgical treatment are essential for acceptable results. For early diagnosis, we emphasized on the presence of roentgenologic mediastinal and cervical emphysema. In patients for whom diagnosis was delayed and post-operative leakage at the oesophageal suture line occurred, temporarily fistulation of the cervical oesophagus proved to be effective in exclusion and diversion of the ruptured segment.

Adult↗
PubMed1989

Comparative study of clinical factors predisposing patients to proliferative vitreoretinopathy.

Clinical features of 57 eyes with proliferative vitreoretinopathy (primary PVR) that developed preoperatively were statistically analyzed and compared with a control group of 1353 eyes with non-PVR rhegmatogenous retinal detachment. The statistically significant (P less than 0.05) factors predisposing to PVR were as follows: retinal detachment for more than 1 month; aphakia (47.4% in the PVR group versus 11.1% in the control group); vitreous hemorrhage (26.3% versus 11.0%); giant tear (15.8% versus 0.8%); breaks larger than 3 disc diameters (62.1% versus 27.3%); and horseshoe tear (65.5% versus 44.9%).

Adolescent↗