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Biomedical subjects

Y Shimoda

Publications and source records attributed to Y Shimoda.

At least 37 records · Page 2Linked to original sources
PubMed1994

Calcium ion binding of three different types of oligo/polysialic acids as studied by equilibrium dialysis and circular dichroic methods.

Ca2+ binding properties of three different types of oligo/polysialic acid chains, i.e., oligo/poly(Neu5Ac), oligo/poly(Neu5Gc), and oligo/poly(KDN), were studied by equilibrium dialysis and circular dichroism. Colominic acid, high molecular weight polysialoglycoprotein (H-PSGP), low molecular weight polysialoglycoprotein (L-PSGP), and 3-deoxy-D-glycero-D-galacto-2-nonulosonic acid (KDN) glycoprotein were found to bind calcium ions with about 8-100 times the affinity of sialic acid monomer. Analysis by equilibrium dialysis of the binding of Ca2+ to colominic acid was biphasic, and the high-affinity interaction was shown to change with the degree of polymerization. Specific binding of Ca2+ to polysialic acid (polySia) caused characteristic effects in the circular dichroism spectrum. A pronounced decrease in the circular dichroism of polySia at 205 nm was observed upon addition of calcium. H-PSGP was found to bind calcium ions with 3-fold higher affinity than L-PSGP.

Animals↗
PubMed1994

Diagnosis of inflammatory pseudotumor of the liver: value of CT.

OBJECTIVE: Inflammatory pseudotumor of the liver is a localized mass consisting of a fibrous stroma and chronic inflammatory infiltrate without anaplasia. Diagnosis of this rare disease is important to avoid surgery. The purpose of this study was to determine if CT is useful in the diagnosis of this lesion. SUBJECTS AND METHODS: CT scans of nine patients with a proved diagnosis of inflammatory pseudotumor of the liver were reviewed. Diagnosis was made by the surgical resection in three patients and by percutaneous biopsy in six patients. Six patients had symptoms and laboratory data suggesting active inflammation caused by the pseudotumor. The remaining three patients were asymptomatic. CT scans were performed with IV administration of the contrast material; scans were obtained in the portal venous and delayed phases in six patients and in the delayed phase in three patients. CT scans were analyzed for the number and size of the hepatic masses, and the degree and pattern of contrast enhancement on portal venous phase and delayed-phase images. RESULTS: Eight patients had a solitary hepatic mass, and one patient had two masses on the CT scan. The average size of the masses in the symptomatic patients (8.3 cm) was larger than that in the asymptomatic group (3.6 cm). CT scans in the portal venous phase showed a variable degree of contrast enhancement (seven masses). At least a part of seven masses, six of which were in symptomatic patients, showed greater contrast enhancement on delayed-phase CT scans than on the normal liver parenchyma. No constant pattern of enhancement was observed on delayed-phase CT scans in asymptomatic patients. CONCLUSION: Inflammatory pseudotumor of the liver should be included in a differential diagnosis in patients with a hepatic mass on a CT scan, especially when patients are symptomatic and the mass is fairly large and solitary showing contrast enhancement greater than that of liver parenchyma on delayed-phase CT scans. Percutaneous biopsy should be performed to obtain a histologic confirmation.

Adolescent↗
PubMed1994

[Informed consent in anesthesia].

Informed consent is required for not only operative procedures but also anesthesia. One hundred and sixty-two patients, including those in a control group, were interviewed between the 3rd and 10th days after operations. An information sheet describes the anesthetic management and complications (possibilities of teeth damage, hoarseness and sore throat) in a simple style. This survey showed that those who had received the information sheet before operation showed significantly deeper understanding of anesthesia (56.2%) compared with those who had not received the information sheet (40.3%) (P < 0.05). The information sheet did not cause or increase anxiety about anesthesia. Those who had anxiety about anesthesia before the operation needed detailed printed information (63.8%) compared with those without anxiety (36.6%) (P < 0.01). An information sheet describing the anesthetic management and complications is useful for obtaining informed consent.

Aged↗
PubMed1993

Colonic submucosal tumors: a new classification based on radiologic characteristics.

OBJECTIVE: Despite advances in gastrointestinal radiologic techniques, findings from barium enema studies cannot be used reliably to predict the histologic nature of a colonic submucosal tumor. Therefore, we generated a new and comprehensive classification system for all colonic submucosal tumors based on a correlation between their radiologic characteristics and their histopathologic features. MATERIALS AND METHODS: Between 1978 and 1990, 89 patients had 95 colonic submucosal tumors diagnosed on the basis of barium enema studies and confirmed by biopsy or surgery. Of these, 39 patients (44%) were symptomatic and 50 patients (56%) were asymptomatic. Single lesions (82 cases) and multiple lesions (12 cases of lymphoma and one case of blue rubber bleb nevus) were observed. The 95 lesions included 21 carcinoids, 27 malignant lymphomas, 17 lipomas, 10 lymphangiomas, six leiomyosarcomas, five leiomyomas, and nine others. We analyzed the radiologic findings and classified these lesions according to their appearance. RESULTS: All tumors were classified on the basis of their morphologic appearance into five types: (1) wide-based sessile lesion with gradually sloping margin and smooth surface (17 cases); (2) wide-based sessile lesion, more polypoid than the first type, with a smooth surface, with or without a central depression (49 cases); (3) wide-based sessile lesion with lobulated surface (six cases); (4) pedunculated lesion with smooth or granular surface (17 cases); (5) unclassified, not any of the previously mentioned types, may be diffusely stenotic or aneurysmal (six cases). The most common finding was the wide-based sessile lesion with a smooth surface and a possible central depression; next most common was the wide-based sessile lesion with gradually sloping margin and smooth surface; next was the pedunculated lesion with a smooth or granular surface. Eighty-six percent of the lesions were single; 14% were multiple. Histologic confirmation revealed mainly lymphoma (29%) and carcinoid (22%), of which the most common finding was a wide-based sessile lesion with a smooth surface, with or without a central depression. CONCLUSION: This new classification based on radiologic characteristics covers all varieties of colonic submucosal tumors. It can serve as a guideline for predicting a specific diagnosis of a colonic submucosal tumor on the basis of radiologic findings.

Adolescent↗
PubMed1993

[Coronary artery spasm under general and epidural anesthesia].

A 66-year-old man without history of angina pectoris was scheduled for subtotal gastrectomy under epidural anesthesia supplemented with nitrous oxide and isoflurane. ECG showed an elevation of ST segment after hypotension. It passed into Wenckebach A-V block and complete A-V block. But an elevation of ST segment was relieved by raising blood pressure and it became sinus rhythm. Serum enzymes (CPK-MB, GOT and LDH) were normal after operation. It is suspected that coronary spasm was induced by hypotension and vagal stimulation under inadequate level of anesthesia, though we could not prove this arteriographically.

Aged↗
PubMed1992

Ultrastructural studies of medullary synaptic inputs to vasopressin-immunoreactive neurons in the supraoptic nucleus of the rat hypothalamus.

Direct projections from the A1/C1 catecholaminergic cell group in the caudal ventrolateral medulla oblongata to neurons containing vasopressin (VP) in the supraoptic nucleus (SON) were studied electron microscopically by a double-labeling technique which combines anterograde tracing after injection of wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) into the A1/C1 cell group with VP immunocytochemistry. WGA-HRP-labeled axon terminals originating from neurons in the A1/C1 cell group were found to make synaptic contacts with VP-immunoreactive cell bodies and dendrites in the SON, most often forming axo-dendritic synapses. This indicates that VP-containing neurosecretory neurons in the SON receive monosynaptic catecholaminergic input from the A1/C1 cell group.

Animals↗
PubMed1992

The effects of urinastatin on the plasma levels of granulocyte elastase during open heart surgery under simple deep hypothermia.

Changes in granulocyte elastase (GLE) and Beta-gluculonidase (Beta-gl) were observed during open heart surgeries which were performed under deep hypothermia with surface cooling. In addition, the effect of urinary trypsin inhibitor, urinastatin, on the activities of these enzymes was studied. The patients were divided into three groups, namely group U-I with intravenous injection of 6000 u.kg(-1) of urinastatin before cooling, group U-II administered with an additional 6000 u.kg(-1) after warming to 30 degrees C, and an untreated group (Group C). The plasma level of GLE increased significantly in the three groups compared with the level before cooling respectively. In the group U-II, the GLE level after the warming was lower than that in the control group. The serum level of Beta-gl increased significantly in the three groups at the end of rewarming (36 degrees C). The release of GLE from lysosomes in granulocytes was inhibited in the group U-II. The insufficient inhibition of GLE release in the group U-I is probably due to relatively short half-life of urinastatin. Therefore double administration of 6000 u.kg(-1), before and after the cooling, may be required to achieve the therapeutic effect. Consequently, urinastatin appears to be useful in open heart surgery under deep hypothermia with surface cooling.

Journal Article↗
PubMed1992

Hyperpolarizing interplexiform cell of the dace retina identified physiologically and morphologically.

One type of interplexiform cell (IPC) in the dace retina was discriminated physiologically from other cell classes and identified morphologically with HRP staining. This type responded with slow hyperpolarizing potentials to white diffuse light, and in addition a slow hyperpolarization (after potential) was observed after the cessation of light with relatively high intensities. The latency of the ON phase of the response was always longer than that of the second-order neurons and the amacrine cells. Morphologically, this type of IPC was similar in appearance with the dopaminergic IPC. The conventional synaptic specialization between this type of IPC and horizontal cells was observed, and the IPC was presynaptic.

Animals↗
PubMed1992

Intestinal anisakiasis: US in diagnosis.

Eighteen consecutive patients with intestinal anisakiasis were studied with high-resolution ultrasound (US) and barium studies. US showed markedly thickened bowel loops associated with luminal narrowing, swelling of Kerckring folds, and decreased peristalsis. A small amount of ascitic fluid around the bowel loops was found, and cytologic examinations of the ascites revealed a dense infiltration of eosinophils. Barium studies demonstrated segmental mucosal edema of the small intestine: The most common site was the distal ileum, and the mean length of the edematous lesion was 19 cm. All patients underwent treatment of symptoms without laparotomy, and their symptoms disappeared by the eighth day after onset. Patients with acute abdominal symptoms should be asked about the intake of raw or undercooked fish. If the above US features are found, the diagnosis of intestinal anisakiasis must be seriously considered to avoid unnecessary surgical treatment.

Adult↗
PubMed1991

Reversal of established nephropathy in New Zealand B/W F1 mice by 15-deoxyspergualin.

The therapeutic effect of 15-deoxyspergualin (DSP) in old New Zealand Black/White F1 mice (B/W mice) with clinical nephropathy was studied and compared with cyclophosphamide (CY). The mice were treated with 0.05 ml phosphate-buffered saline, subcutaneously, four times/week, with DSP, 6 mg/kg body weight, s.c., four times/week, or with CY, 15 mg/kg, i.p., once a week, starting at the 28th week of age. They were serially semiquantitated for proteinuria, and serum IgG anti-dsDNA antibody was measured by ELISA. Spleen cell surface markers such as L3T4, Lyt2 and IgG were flow-cytometrically analyzed, and interleukin-2 (IL-2) activity in vitro was measured using CTLL cells. Kidney specimens were studied with light and immunofluorescence microscopy. The mice treated with either CY or DSP survived significantly longer than the control mice. L3T4+ cells in the DSP-treated mice at 40 weeks of age were significantly less than those in the 28-week-old control mice (p less than 0.05). In contrast, IL-2 generation in the three groups of mice showed no significant variations at 32-40 weeks of age. Serum anti-DNA antibody levels in both of the CY and DSP groups remained low and comparable with that in the 28-week-old mice, and the incidence of significant proteinuria decreased. Likewise, glomerular histology in the treated groups was improved compared with the 28-week-old control mice, and the deposition of IgG and C3 in the treated groups remained unchanged or further decreased. Accordingly, the renal (immuno)histological findings in the DSP group were quite comparable with or even better than those in the CY-treated mice. DSP may have suppressed the abnormal antibody production by modulating the T cell function(s), which is in contrast to the direct action against B cells due to CY.

Animals↗
PubMed1991

[Two cases of pulmonary edema during and after cesarean section].

Pulmonary edema occurred during and after Cesarean section under general anesthesia in two pregnant women. They had no preoperative complication. After delivery, anesthesia was maintained with 66% N2O in oxygen and intravenous injection of pentazocine and diazepam. At the same time, 0.2 mg of methylergometrin was injected intramuscularly and 2,000 micrograms of prostaglandin F2 alpha was injected to the muscle of the uterus in order to induce uterine contraction. In one case, SpO2 dropped and airway pressure increased immediately after the administration. In another case, chest rale was auscultated on postoperative round at 2 hours after operation. The cases suggest that pulmonary edema was caused by a large quantity of oxytocics, which increased volume load on systemic circulation.

Adult↗
PubMed1989

[Case report on the Ehlers-Danlos syndrome].

The Ehlers-Danlos syndrome is a hereditary disease of the connective tissue, characterized by tendencies of hyperextensibility and fragility of the skin, and hypermobility of the joints. We are reporting in this paper on a 4 year, 4 month old boy with the Ehlers-Danlos syndrome, Type III. The following findings were obtained: 1) In addition to the three main symptoms the complications of exotropia, low position of the auricle, defect of the right musculuspectoralis major, right double thumbs, dislocation of hip joint, right inguinal hernia, right undescended testis and pes planovalgus were found. 2) Based on histopathological tissue examination, hypoplasia of the collagen fibers and the elastic fibers was found. 3) The occlusion was edge to edge, the plate was high arched and the upper and the lower dental arches were contracted. 4) The mesiodistal lengths of all primary teeth and the lengths and widths of the dental arches were smaller than the standard size. 5) The orthopantomo and dental x-rays revealed a tendency toward late calcification of the deciduous teeth and permanent teeth germs, and the stricture of the root canals. 6) According to x-ray cephalometric analysis, retardation of the growth of the upper face as well as the maxilla and mandibula was found.

Child, Preschool↗
PubMed1989

[Study of pit and fissure sealants. The effect of viscosity of the sealants and type of the applicators on the administration time and the sealed area].

From the standpoint of the durability of the sealants, it is assumed that the sealants should be applied only to the bottom part of the pit and fissure to avoid marginal fracture and wear of the materials. Because of this, a minimum area for the sealant to be applied is required for a stable prevention of dental caries. The purpose of this study was to investigate the effect of viscosity of the sealants and various applicators in the techniques for minimum-area-sealing. Three sealants with various degrees of viscosity were applied to the stone models of a lower first molar by means of four types of applicators. Three operators conducting the experiment were a dentist with two years of experience, a dentist with one year of experience and a student. The time required for administration and the area of sealed pits and fissures were evaluated. The following results were obtained. 1. The sealants with a lower degree of viscosity revealed a shorter administration time and a narrower sealed area. 2. The applicators with thinner nozzles brought about a shorter administration time and a narrower sealed area. 3. The administration time did not exhibit significant differences among the operators, while the sealed area exhibited significant differences. 4. The longer the period of the clinical experience of the operator, the narrower the sealed area obtained. From the above results, it is recommended to select a sealant with low viscosity and utilize an applicator with a thin nozzle or a brush with a fine tip to obtain the minimum-sealing-area. Additionally, prior to the clinical trial, one should become acquainted with the characteristics of the sealant as well as the manipulation of the applicator.

Pit and Fissure Sealants↗
PubMed1989

[Analysis of P-glycoprotein in patients with acute leukemias by flow cytometry].

The identification of a P-glycoprotein product of multidrug-resistant gene (mdr 1) was reported recently. To examine the expression of the P-glycoprotein in acute leukemias of various types, we have prepared leukemic blast cells from patients and measured their positivity of P-glycoprotein using monoclonal anti-P-glycoprotein antibody (C219) by flow cytometry. P-glycoprotein is expressed in 8 out of 44 cases including leukemic blast cells but not lymphocytes and monocytes. In these cases showed drug resistance was shown clinically. In addition, the expression of the P-glycoprotein was not observed in the drug-sensitive cases and at the time of initial chemotherapy. Our results suggest that measurement of P-glycoprotein in acute leukemias by flow cytometry may prove to be a valuable tool for the design of chemotherapy protocols.

ATP Binding Cassette Transporter, Subfamily B, Mem↗