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Biomedical subjects

Y Oike

Publications and source records attributed to Y Oike.

At least 55 records · Page 3Linked to original sources
PubMed1990

[Evaluation of left ventricular mechanical energy efficiency and ventriculo-arterial coupling in humans using the conductance catheter technique].

To evaluate left ventricular mechanical energy efficiency and ventriculo-arterial coupling in humans, left ventricular pressure-volume relations were determined using the conductance catheter technique in 20 patients undergoing cardiac catheterization. The results were as follows: 1. A convex, curvilinear relationship was observed between end-systolic pressure-volume relations (Emax) and left ventricular ejection fraction (EF), as shown in the equation of EF = 28.5 x log (Emax) + 39.6 (r = 0.67, p less than 0.01, n = 20); EF remained nearly constant in the range of Emax greater than or equal to 4 mmHg/ml/m2, whereas, EF decreased markedly under the Emax of 4 mmHg/ml/m2. 2. A convex, curvilinear relationship was observed between Emax and mechanical energy efficiency (EW/PVA), as shown in the equation of EW/PVA = 30.5 x log (Emax) + 54.8 (r = 0.83, p less than 0.01, n = 16). 3. A concave, curvilinear relationship was observed between Emax and ventriculo-arterial coupling (Ea/Emax), as shown in the equation of Ea/Emax = -0.8 x (Emax)0.5 + 2.6 (r = -0.85, p less than 0.01, n = 16). Accordingly, EW/PVA was markedly decreased with changes in Emax in the range less than 4 mmHg/ml/m2, although it remained slightly increased above 4 mmHg/ml/m2. Ea/Emax was maintained constant (p less than 0.5) in the range of Emax above 4 mmHg/ml/m2 but was abruptly decreased when Emax was reduced below 4 mmHg/ml/m2. These results indicate that depressed left ventricle attempts to work effectively at the risk of mechanical energy efficiency and with suitable matching by aortic property. Application of pressure-volume relationships provides a new framework for evaluation and treatment of the failing heart.

Adolescent↗
PubMed1989

[Coronary hemodynamics in a patient developing chest pain in the middle age in congenital coronary-pulmonary fistula].

Recently reports of congenital coronary-pulmonary fistula have been increasing with the wide-spread use of coronary angiography. However, the cause of the angina sometimes seen as a chief complaint in coronary fistula has not been well demonstrated although it has been suggested that coronary steal phenomenon accounts for it. This report documented coronary hemodynamics in a patient who came to develop anterior chest pain in the middle age owing to congenital coronary-pulmonary fistula, measuring coronary flow before and after the fistula-closure operation. A 35-year-old woman suffered from a sudden onset of severe anterior chest pain in April, 1986. She was referred to our hospital on suspicion of ruptured aneurysm of Valsalva. Auscultation disclosed continuous murmur at 3 LSB, but no evidence of ruptured aneurysm of Valsalva was detected by echocardiography nor aortography. Coronary angiography showed both left and right coronary fistula into the stem of pulmonary artery and otherwise normal angiogram. Great cardiac vein flow (GCVF) measured with regional thermodilution method was 25 ml/min at rest (70 bpm) and 30 ml/min during rapid atrial pacing (150 bpm) before the operation, and 30 ml/min (78 bpm) and 58 ml/min (150 bpm) after the operation, respectively. Before the surgery, anterior coronary resistance (CRant) was higher than that in normal subjects at rest and remained almost steady during atrial pacing. After the surgery, CRant was still higher at rest but remarkably reduced during pacing of 150 bpm. These findings suggest that the gradual increase in peripheral coronary resistance for a long time may lead to the inducement of coronary steal in the middle-later age in patients with coronary fistula.

Adult↗
PubMed1989

[A case of myocardial infarction due to the left main trunk lesion, in which percutaneous coronary recanalization and emergency coronary-aorto bypass graft, and subsequent percutaneous coronary angioplasty were effective not only from a viewpoint of survival but from comeback to social life].

A case of acute myocardial infarction due to the lesion in the left main coronary artery was reported. A 50-year male was referred to our department for suspected acute myocardial infarction. Physical examination on admission revealed slight cyanosis with cold sweating due to severe chest pain. Pulse was irregular and heart rate was 78 beats/min. Blood pressure was 100/80 mmHg. A series of electrocardiograms (ECG) and laboratory data provided the diagnosis of wide-ranged anterolateral infarction in the left ventricle. Emergency coronary angiograms taken without delay showed a subtotal occlusion (99% stenosis) of the left main coronary trunk (LMT) before the initiation of intracoronary thrombolysis (PTCR). Following the intracoronary infusion of urokinase of 1,200,000 units, symptoms and ECG changes transiently improved but worsened later, and LMT stenotic lesion and delayed filling of myocardium were similar with before PTCR. Emergency coronary-aorto bypass graft (CABG) was undertaken without a significant delay to both the left anterior descending artery (LAD) and left circumflex coronary artery (LCX). With these treatments, the patient could survive despite the wide area of infarction due to LMT lesion. Coronary angiograms performed 37 days after the CABG showed that the graft to LAD was completely occluded and the LCX graft was patent with partial stenosis. Treadmill test at this time induced an anginal episode with ischemic ECG changes on moderate exercise, indicating the presence of significant area of ischemic myocardium. For salvage of the ischemic myocardium, percutaneous transluminal coronary angioplasty (PTCA) was successfully performed for the LMT stenosis, resulting in no episode of angina nor ischemic ECG changes during exercise loading.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty, Balloon, Coronary↗
PubMed1989

[A case of left atrial ball thrombus observed in a patient with combined valvular heart disease, accompanying anomalous coronary venous run].

A 53-year woman, who had been under observation for combined valvular heart disease, was admitted to our hospital for further examination of embolic episodes to brain and kidney. Echocardiographic examination showed the evidence of free-moving ball thrombus in the left atrium, and emergent cardiac catheterization following the echocardiography confirmed the diagnosis of it as well as mitral stenosis, aortic regurgitation with stenosis, and tricuspid regurgitation. In addition, coronary angiography disclosed the anomalous coronary venous run. With these findings, the cause of embolic episodes was found to be due to the thrombus in the left atrium. In the surgery performed a ball thrombus of 40 x 35 x 36 mm and a mural thrombus of 15 x 35 x 20 mm in size in the left atrium were detected and removed, and both mitral and aortic valves were replaced to artificial ones. She had a good hospital course after the surgery and discharged without any complication. In this report, we discussed a case of left atrial thrombus observed in a combined valvular heart disease, with 29 literatures reported in our country.

Coronary Vessel Anomalies↗
PubMed1988

Immunofluorescent localization of tenascin during development of the mouse urogenital sinus: possible involvement in genital duct morphogenesis.

Tenascin is a compound of the mesenchymal extracellular matrix and has been proposed as a possible mediator in epithelial-mesenchymal interactions, because of its characteristic distribution in tissues during fetal development. In the present study, we have investigated by immunofluorescence the changes in the distribution of tenascin during development of the mouse urogenital sinus, a process in which tissue interactions were found to be essential. Tenascin first appears in dorsal mesenchyme on days 13-15 of gestation, coinciding with morphological changes of the epithelium. During male development, tenascin accumulates in the dorsal mesenchyme around the junction of Wolffian ducts, but not in the ventral mesenchyme, into which prostatic buds (prostate gland anlagen) project from the sinus epithelium. During female development, the mesenchyme that participates in the downgrowth of the vagina (derived from Müllerian ducts) stains intensively for tenascin. In both of these tenascin-positive areas, the epithelium undergoes conspicuous morphogenetic changes. The results suggest that mesenchymal tenascin could be involved in the epithelial morphogenesis of the sinus, especially in the morphogenesis of the genital ducts.

Animals↗
PubMed1987

A monoclonal antibody that specifically recognizes a glucuronic acid 2-sulfate-containing determinant in intact chondroitin sulfate chain.

Monoclonal antibodies produced against chick embryo limb bud proteoglycan (PG-M) were selected for their ability to recognize determinants on intact chondroitin sulfate chains. One of these monoclonal antibodies (IgM; designated MO-225) reacts with PG-M, chick embryo cartilage proteoglycans (PG-H, PG-Lb, and PG-Lt), and bovine nasal cartilage proteoglycan, but not with Swarm rat chondrosarcoma proteoglycan. The reactivity of PG-H to MO-225 is not affected by keratanase digestion but is completely abolished after chondroitinase digestion. Competitive binding analyses with various glycosaminoglycan samples indicate that the determinant recognized by MO-225 resides in a D-glucuronic acid 2-sulfate(beta 1----3)N-acetylgalactosamine 6-sulfate disaccharide unit (D-unit) common to antigenic chondroitin sulfates. A tetrasaccharide trisulfate containing D-unit at the reducing end is the smallest chondroitin sulfate fragment that can inhibit the binding of the antibody to PG-H. Decreasing the size of a D-unit-rich chondroitin sulfate by hyaluronidase digestion results in progressive reduction in its inhibitory activity. The results suggest that the epitope has a requirement for a long stretch of a disaccharide-repeating structure for a better fit to the antibody.

Animals↗
PubMed1987

Comparison among lipid constituents in native LDL, ultra-water-soluble LDL, and vessel wall, and their significance in arteriosclerosis.

The lipid constituents in native low-density lipoproteins (LDL), ultra-water-soluble LDL (UWS-LDL), and aortic intimal tissues were compared. These lipoproteins were obtained from healthy persons and patients with atherosclerotic diseases. Also, aortic intimas were separated from arterial walls obtained within 5 hr after the donor's death. (1) From the native LDL, cholesterol esters (CE), triglycerides (TG), small amounts of free fatty cid (FFA), free cholesterol (CF), and phospholipids (PL) were demonstrable by iodine vapor on TLC, but from UWS-LDL the above lipids plus a new lipid (spot X) were observed between TG and FFA on TLC. And also, an unknown spot with the same Rf value as spot X was recognized on TLC of lipid extract from the atherosclerotic lesion, but not from the normal intima. (2) The production of spot X in UWS-LDL is probably related to the oxidation of lipids in native LDL. Also, the spot X in UWS-LDL and the spot X in the atherosclerotic lesions are probably related to the oxidation of CE in these lipids. (3) The existence of UWS-LDL is important to the initiation and probably the progression of atherosclerosis.

Aorta↗
PubMed1986

A large chondroitin sulfate proteoglycan (PG-M) synthesized before chondrogenesis in the limb bud of chick embryo.

Extraction of stage 22-23 chick embryo limb buds that had been metabolically labeled with [35S]sulfate yielded heparan sulfate proteoglycan, small chondroitin sulfate proteoglycan, and large chondroitin sulfate proteoglycan (designated PG-M). PG-M constituted over 60% of the total macromolecular [35S]sulfates. It was larger in hydrodynamic size, richer in protein, and contained fewer chondroitin sulfate chains as compared to the predominant proteoglycan (PG-H, Mr congruent to 1.5 X 10(6)) of chick embryo cartilage. The chondroitin sulfate chains were notable for their large size (Mr greater than or equal to 60,000) and high content of nonsulfated chondroitin units (about 20% of the total hexosamine). Hexosamine-containing chains corresponding in size to N-linked and O-linked oligosaccharides were also present. The core protein was rich in serine, glutamic acid (glutamine), and glycine which together comprised about 38% of the total amino acids. Following chondroitinase AC II (or ABC) digestion, core molecules were obtained which migrated on sodium dodecyl sulfate gel electrophoresis as a doublet of bands with approximately Mr = 550,000 (major) and 500,000, respectively. The Mr = 550,000 core glycoprotein was structurally different from the core glycoprotein (Mr congruent to 400,000) of PG-H, as ascertained by tryptic peptide mapping and immunochemical criteria. Immunofluorescent localization of PG-M showed that the intensity of PG-M staining progressively became higher in the core mesenchyme region than in the peripheral loose mesenchyme, closely following the condensation of mesenchymal cells. Since the cell condensation process has been shown to begin with the increase of fibronectin and type I collagen concentration, the similar change in PG-M distribution suggests that PG-M plays an important role in the cell condensation process by means of its interaction with fibronectin and type I collagen.

Animals↗
PubMed1986

Evolution of HBeAg/anti-HBe status and its relationship to clinical and histological outcome in chronic HBV carriers in childhood.

Fifty-five Japanese HBV carriers under 15 yr of age were followed for 12 months or longer, during which time we investigated the evolution of HBeAg/anti-HBe status and clinical and histological aspects of the liver disease. Of 45 cases positive for HBeAg at the initial examination, 34 remained positive for HBeAg during the follow-up periods, while the remaining 11 lost HBeAg and eight of these seroconverted to anti-HBe. At the final observation, HBeAg positivity in serum was found in as many as approximately 90% of the HBV carriers under 6 yr, but had fallen to 48% in carriers between 12 and 15 yr. The serum transaminase values in 11 cases who lost HBeAg were abnormally elevated for variable periods, but eventually returned to normal. In six of these 11 who had liver dysfunctions, liver biopsy was performed during the HBeAg positive phase or shortly after the disappearance of HBeAg. The histologies of liver were chronic persistent hepatitis in two cases and chronic active hepatitis in four. Repeat liver biopsies of two cases with chronic active hepatitis at the first examination showed nonspecific reactive hepatitis 2 and 4 yr after seroconversion or disappearance of HBeAg. These results indicate that HBeAg-positive HBV carriers with overt liver dysfunctions in childhood are prone to lose HBeAg or to seroconvert to anti-HBe, followed by a marked histological regression, and therefore that special antiviral therapy is probably unnecessary.

Adolescent↗
PubMed1985

Selective removal of heparan sulfate chains from proteoheparan sulfate with a commercial preparation of heparitinase.

Procedures employing the commercial preparation of heparitinase were developed for isolating a protein-enriched core molecule from proteoheparan sulfate by selective removal of the heparan sulfate chains. Treatment of proteoheparan sulfate with the enzyme preparation caused seriously extensive degradation owing to the presence of proteolytic activity in the enzyme preparation. This effect could be avoided by using a series of protease inhibitors which prevented proteolytic degradation with less significant effect on the heparitinase activity. Application of the procedures to a purified preparation from the Engelbreth-Holm-Swarm tumor yielded a single protein-enriched core fraction with a molecular weight of approximately 450,000, as ascertained by sodium dodceyl sulfate-gel electrophoresis.

Animals↗
PubMed1985

The core molecule from type H proteoglycan. Release of mannose-containing oligosaccharides by digestion with N-oligosaccharide glycopeptidase.

Chick-embryo cartilage contains a unique set of proteoglycans. Type H proteoglycan (PG-H) is the most abundant, constituting over 90% of the total cartilage hexuronate. We previously showed that treatment of PG-H with chondroitinase ACII and keratanase yields a protein-enriched core molecule [PG(-CS,KS)] with enzymically modified linkage oligosaccharides of the chondroitin sulphate and keratan sulphate chains. We report here that further treatment of PG(-CS,KS) with pepsin and N-oligosaccharide glycopeptidase (almond glycopeptidase) released four distinct types of mannose-containing oligosaccharide. Two of them were shown to be: (Formula: see text). Of the mannose-containing glycopeptides formed by pepsin digestion, about 40% (as mannose) were resistant to N-oligosaccharide glycopeptidase. Since the resistant fraction was enriched in keratan sulphate remnants, it is suggest that the mannose-containing oligosaccharides in this fraction represent those located in a keratan sulphate-enriched region of PG-H.

Amidohydrolases↗