Biomedical subjects

M Kawase

Publications and source records attributed to M Kawase.

At least 109 records · Page 6Linked to original sources

PubMed1996

Changes in concentrations of methylglyoxal, D-lactate and glyoxalase activities in liver and plasma of rats fed a 3'-methyl-4-dimethylaminoazobenzene-rich diet.

Donryu male albino rats were fed a diet containing 0.064% 3'-methyl-4-dimethylaminoazobenzene (MDAB) for 21 weeks. During the ensuing rat liver carcinogenesis, changes in the concentrations of methylglyoxal, D-lactate and glutathione as well as activities of glyoxalase I and II in liver and plasma were examined. After the start of the diet, hepatic contents of methylglyoxal and D-lactate increased to about 7 and 3 times that of the control, respectively. However, after 21 weeks the D-lactate content decreased from the elevated level, but remained at a higher level of 1.4 times the control. The hepatic glyoxalase I activity increased 1.2 to 1.7 times over the control during carcinogenesis, while glyoxalase II activity increased 160% during the precancerous state and decreased to 55% of control at 21 weeks. the hepatic level of reduced glutathione (GSH) increased and peaked after 4 weeks of the MDAB diet and decreased thereafter to 57% of the control level after 21 weeks. Both pyruvate and L-lactate levels increased in the liver and plasma of MDAB-fed rats when rats had obvious symptoms of hepatoma.

Alanine Transaminase↗

PubMed1996

Spinal malignant lymphoma appearing after radiation and chemotherapy of a pineal region tumor.

The occurrence of malignant lymphoma in the pineal region is very rare. We experienced a case of pineal region tumor that was treated by radiation and chemotherapy. After 1 year, the tumor metastasized to the cauda equina and was operated on. The diagnosis was malignant lymphoma. Although the incidence of intracranial malignant lymphoma is known to be on the increase recently, malignant lymphoma should be considered in the differential diagnosis of pineal region tumors.

Adolescent↗

PubMed1996

Biosynthesis of Poly(3-Hydroxyalkanoic Acid) Copolymer from CO(inf2) in Pseudomonas acidophila through Introduction of the DNA Fragment Responsible for Chemolithoautotrophic Growth of Alcaligenes hydrogenophilus.

Pseudomonas acidophila is a bacterial strain producing a poly(3-hydroxyalkanoic acid) (PHA) copolymer from low-molecular-weight organic compounds such as formate and acetate. The genes responsible for PHA production were cloned in cosmid pIK7 containing a 14.8-kb HindIII fragment of P. acidophila DNA. With the aim of developing a means of producing a PHA copolymer from CO(inf2), cosmid pIK7 was introduced into a polymer-negative mutant of the chemolithoautotrophic bacterium Alcaligenes eutrophus PHB(sup-)4. However, the recombinant strain produced a homopolymer of 3-hydroxybutyric acid (polyhydroxybutyric acid) from CO(inf2). Since it was thought that the composition of the accumulated polymer might depend not on the PHA biosynthetic genes but on the metabolism of the host strain, a recombinant plasmid, pFUS, containing the genes for chemolithoautotrophic growth of the hydrogen-oxidizing bacterium A. hydrogenophilus was introduced into P. acidophila by conjugation. The recombinant plasmid pFUS was stably maintained in P. acidophila in the absence of chemolithoautotrophic or antibiotic selection. This pFUS-harboring strain possessed the ability to grow under a gas mixture of H(inf2), O(inf2), and CO(inf2) in a mineral salts medium, and PHA copolymer accumulation was confirmed by nuclear magnetic resonance spectral analysis. A gas chromatogram obtained by gas chromatography-mass spectrometry showed the composition of the polymer to be 52.8% 3-hydroxybutyrate, 41.1% 3-hydroxyoctanoate, and 6.1% 3-hydroxydecanoate. This is the first report of the production of a PHA copolymer from CO(inf2) as sole carbon source.

Journal Article↗

PubMed1996

Reconstruction of dilated aortic annulus using short tubular Dacron graft for aortic root replacement by aortic homograft--a solution for size mismatch.

To circumvent the problems associated with a dilated aortic annulus we first reduced the diameter of the annulus with a short section of Dacron graft and then implanted a smaller size homograft within the graft. This procedure was successfully performed for complete homograft aortic root replacement in a 25-year-old man with severe aortic insufficiency due to a dilated aortic annulus. The indication for homograft replacement can thus be widened, even to patients with a dilated aortic annulus.

Adult↗

PubMed1996

[Left free wall rupture complicating acute myocardial infarction--a case report of surgical success by a new modified method].

The success rate of surgical treatment for blowout type free wall rupture of the left ventricle following myocardial infarction has been reported as 4 to 24%. A 64-year-old woman was admitted to our hospital for inferior acute myocardial infarction with cardiogenic shock. In the catheter laboratory, her hemodynamics disclosed electro-mechanical dissociation, and we had to perform an emergent operation there. In order to preserve left ventricular volume and reduce the risk of bleeding, we adopted a modified method using both patch and felt strip sandwich methods which obtained favorable result. The patient was sent to a rehabilitation hospital on the 43rd post operative day because of a mild cerebral complication and she is now doing well with only a slight speaking disturbance at a follow-up period of 10 months.

Cardiac Surgical Procedures↗

PubMed1995

Contents of D-lactate and its related metabolites as well as enzyme activities in the liver, muscle and blood plasma of aging rats.

As it is generally known. L-lactate is formed via the Embden-Meyerhof glycolytic pathway from triosephosphates, whereas D-lactate is formed via methylglyoxal in rat. In this paper, age-related changes in the levels of D-lactate and its related compounds in rat tissues are reported. Rats from 5 weeks to 30 months old were used in these experiments. (1) We observed that rats above 27 months old were decrepit as judged by external appearance movement and other physiological data of them. (2) The hepatic levels of D-lactate, methylglyoxal and pyruvate became markedly lower in aging rats, especially the D-lactate content in 30 month-old rats was lower by 90% than that of the 5 week-old rats. (3) As for plasma, D-lactate and phosphate levels became lower with aging, whereas levels of L-lactate and pyruvate were not altered. (4) In skeletal muscle, aging caused a lower methylglyoxal concentration. The D-lactate level was markedly decreased at the age of 30 months in muscle. (5) As for enzyme, activities of glyoxalase I and II became markedly decreased with age in livers, whereas the activity of glyoxalase I in muscle was maintained at control level and glyoxalase II increased with age.

Aging↗

PubMed1995

Most of the VP1 unique region of B19 parvovirus is on the capsid surface.

B19 parvovirus is pathogenic in man and a vaccine is desirable. In convalescence after acute infection, the dominant humoral immune response is directed to the minor capsid protein called VP1, which differs from the major capsid protein by an additional NH2-terminal 227 amino acids. We have previously shown that this unique region contains multiple linear neutralizing epitopes. We produced seven recombinant B19 capsids that contained progressively truncated VP1 unique region sequences, each fused to a Flag peptide (AspTyrLysAspAspAspAspLys) at the NH2-terminus. Capsids containing normal VP2 and truncated Flag-VP1 proteins and, in some cases, only truncated Flag-VP1 chimeric proteins, were analyzed by ELISA, affinity chromatography, and electron microscopy using anti-Flag monoclonal antibody. All regions examined showed binding to anti-Flag antibody in multiple assays, indicating that most of the VP1 unique region is external to the capsid and accessible to antibody binding. These results have implications for the design of a B19 parvovirus vaccine and the use of empty capsids for presentation of heterologous protein antigens.

Amino Acid Sequence↗

PubMed1995

Peptides derived from the unique region of B19 parvovirus minor capsid protein elicit neutralizing antibodies in rabbits.

B19 parvovirus is pathogenic in humans. The virus propagates in the bone marrow, where it is cytotoxic to erythroid progenitor cells. Antibodies appear in blood after infection and neutralize virus in vitro; infection appears to confer lasting immunity. The predominant immune response on immunoblot is to the minor capsid protein (VP1), which differs from the major capsid protein (VP2) by an additional 227 amino acids. We previously demonstrated that antisera directed to a fusion protein containing this unique region or to more limited fusion peptides of 50-100 amino acids each neutralized virus. In the current work, we tested synthetic peptides of about 20 amino acids derived from the VP1 unique region for their ability to elicit a neutralizing antibody response in rabbits. Individual peptides were covalently linked to a lysine core to produce a multivalent antigen. Animals produced antibodies to all 13 synthetic peptides, as determined by ELISA. At 12 weeks, animals injected with one of three peptides--two from the far amino terminus and the third from the center of the unique region--had produced antibodies that completely neutralized virus; by 16 weeks, antisera elicited with another four peptides also were effective. In summary, we identified regions containing neutralizing epitopes within the first 80 amino acids and amino acids 148-205 of the unique region. Our data suggest that synthetic peptides might be useful vaccine reagents for protection against parvovirus infection in humans.

Amino Acid Sequence↗

PubMed1995

Purification of functional recombinant YY1 expressed in Sf9 insect cells.

We expressed a gene for YY1, the multifunctional mammalian transcription factor, with a recombinant baculovirus in insect cells and obtained high levels of protein in cell lysates. A simple and efficient purification method was developed. In the final step, we used DNA affinity chromatography with concatermerized sequence derived from the upstream region of the B19 parvovirus P6 promoter, which has strong affinity for YY1. Approximately 1.8 mg of highly purified YY1 was obtained from 10(9) Sf9 cells. Highly purified YY1 behaved as authentic YY1 on electrophoretic mobility shift assays and in enhancing transcription from the P6 promoter. YY1 produced in a baculovirus system should prove useful for in vitro transcription assays of YY1 and related regulatory proteins.

Animals↗

PubMed1995

Modest truncation of the major capsid protein abrogates B19 parvovirus capsid formation.

In vitro studies have suggested an important role for the minor capsid protein (VP1) unique region and the junction between VP1 and the major capsid protein (VP2) in the neutralizing immune response to B19 parvovirus. We investigated the role of the NH2-terminal region of the major structural protein in capsid structure by expressing progressively more truncated versions of the VP2 gene followed by analysis using immunoblotting and electron microscopy of density gradient-purified particles. Deletion of the first 25 amino acids (aa) of VP2 did not affect capsid assembly. Altered VP2 with truncations to aa 26 to 30, including a single amino acid deletion at position 25, failed to self-assemble but did participate with normal VP2 in the capsid structure. The altered region corresponds to the beginning of the beta A antiparallel strand. Truncations beyond aa 30 were incompatible with either self-assembly or coassembly, probably because of deletion of the beta B strand, which helps to form the core structure of the virus.

Amino Acid Sequence↗

PubMed1995

[Mitral valve plasty for better long term results].

Between July 1991 and January 1995, 74 patients with pure mitral valve regurgitation (MR) underwent mitral valve plasty (MVP) at out institute. Our procedure includes chordal replacement of the anterior leaflet with PTFE sutures (42 patients). There were one hospital death (1.4%) and two late deaths (2.7%) in this series. Only 2 patients (2.7%) needed valve replacement after unsatisfactory repair during the same operation. Late postoperative doppler echocardiographic study (mean follow-up, 12.0 months) showed less than mild regurgitation in 66 patients (95.7%) of 69 patients who are alive. In April 1993 we decided to complete the repair with no or only trivial regurgitant flow by intraoperative transesophageal echodoppler study (TEE). The results have remarkably improved. Late postoperative echodoppler study revealed less than mild reguritant flow in all 49 patients having undergone mitral valve repair with no or trivial regurgitation by intraoperative TEE. It is clear than the TEE study has contributed to the better quality of mitral valve plasty, and we believe that it is important for better long term results to complete mitral valve plasty with no or only trivial regurgitant flow.

Adult↗

PubMed1995

Serial transesophageal echocardiography imaging of a postoperative aortic ring abscess: a case report.

Transesophageal echocardiography (TEE) was used for the serial observation of a postoperative perivalvular abscess of a prosthetic aortic valve in a 65-year-old man who underwent aortic valve replacement for aortic regurgitation. Five months later, TEE revealed an aortic ring abscess. Ascending aortic grafting (Bentall method) and translocation of the aortic prosthetic valve were conducted for progressive mechanical valve dysfunction. Postoperative TEE showed flow between the left ventricular outflow tract and the abscess, which was unrestricted 1 month later. Associated clinical improvement suggested that washout of the abscess was a critical factor. This case illustrates the usefulness of TEE for examining postoperative aortic ring abscess.

Abscess↗

PubMed1995

[A case report of annuloaortic ectasia with coarctation of the aorta and "high take off" of the right coronary artery].

A 21-year-old male who had annuloaortic ectasia with coarctation of the aorta and "high take off" of the right coronary artery underwent two stage operations. A bypass operation using an artificial graft was performed for coarctation of the aorta at the first procedure. The second procedure, Cabrol's operation, was performed on 83rd day after the first operation. At the second operation we found "high take off" of the right coronary artery. The right coronary artery originated about five centimeters above the rim of the left sinus of Valsalva. Post-operative cause was uneventful. Annuloaortic ectasia combined with coarctation of the aorta and "high take off" of the right coronary artery is very rare in the literature.

Adult↗

PubMed1995

[Occlusion of left coronary ostium involving aortic stenosis and insufficiency].

Aortic valve replacement combined with enlargement of the valvar ring by the Nicks method and coronary artery bypass grafting via the left internal thoracic artery were performed for an 11-year-old girl with occlusion of the left coronary ostium. The left coronary sinus was covered with membranous tissue, so the left coronary ostium was not found. Aortic valve replacement with 21 mm prosthetic valve was possible by enlarging the valvar ring. The internal thoracic artery which is expected to grow with development of the body was used as the graft.

Aortic Valve Insufficiency↗

PubMed1994

Production of human PTH(1-34) via a recombinant DNA technique.

The production of hPTH(1-34) by site specific chemical cleavage of [Cys35]hPTH(1-84) obtained by a biotechnology technique is described. The amino-peptide bond of S-cyanylated cysteine residues in peptides or proteins is specifically cleaved by exposure to an alkaline solution (Stark, G. R. (1977) Methods Enzymol, 47, 129-132). However, when applying this method to [Cys35]hPTH(1-84), we observed many by-products. Formation of these by-products was suppressed using a short reaction in 0.03N NaOH containing 6M urea at low temperature, and hPTH(1-34) was specifically produced. The product was indistinguishable from standard hPTH(1-34) with respect to chemical and biological characterization.

Amino Acid Sequence↗

PubMed1994

The successful surgical repair of a left ventricular-right atrial communication and aneurysm of the mitral valve caused by infective endocarditis: report of a case.

We report herein the case of a 42-year-old man who developed a left ventricular-right atrial communication and aneurysm of the mitral valve caused by infective endocarditis, which was associated with aortic regurgitation. Based on the findings of congestive heart failure, prolongation of the PR interval, and the added threat of rupture of the mitral aneurysm, surgical treatment was decided upon as the best course of action. The aortic and mitral valves were replaced with prosthetic mechanical valves, and the septal communication was simultaneously closed with a patch. The patient's postoperative course was uneventful and he has been in good health since. Thus, we believe that aggressive surgical intervention for complicated lesions such as those seen in our patient may be life-saving, even in the presence of inflammatory signs.

Adult↗

PubMed1994

Simple method for determining proper length of artificial chordae in mitral valve repair.

A simple method for determining the length of artificial chordae in mitral reconstructive operations is described. A small tourniquet is used for fine adjustment of the length of polytetrafluoroethylene stitches before tying them during leaking test. We have used this technique in 10 consecutive patients with anterior mitral leaflet prolapse since August 1992. Intraoperative transesophageal echocardiography revealed no or only trace mitral regurgitation after valve repair in all cases. This method minimized the time of determining the proper length of artificial chordae and achieved good results.

Chordae Tendineae↗

PubMed1994

Carbon sources for D-lactate formation in rat liver.

Carbon sources for D-lactate formation were investigated in vitro using 6,000 x g supernatant of rat liver homogenate and by rat liver perfusion in situ. As carbon sources, L-threonine, glucose, glycerol, acetone, and acetoacetate were tested. Glycerol was the best substrate for D-lactate formation via methylglyoxal in rat liver. Glucose was the second most preferred substrate, while L-threonine, acetone, and acetoacetate were poor substrates for D-lactate formation. Glycerol was several times more effective than normal as a substrate of D-lactate in the supernatants of liver homogenates of diabetic and starved rats, while it was less effective as a substrate of L-lactate. The glycerol kinase [EC 2.7.1.30] activities in livers increased in the diabetic and starved states. These and other results can explain why the plasma concentration of D-lactate increases several-fold after running and why the D-lactate contents in plasma, liver, and skeletal muscle are markedly increases in diabetic and starved rats.

Acetoacetates↗