Search PubMed⌕ Search

Biomedical subjects

H Yasui

Publications and source records attributed to H Yasui.

At least 253 records · Page 14Linked to original sources
PubMed1992

[Successful intrauterine digoxin therapy for fetal complete atrioventricular block with endocardial cushion defect: a case report].

We report herein a case of fetal complete atrioventricular block accompanied with endocardial cushion defect, successfully diagnosed and treated, in utero, with transplacental digitalization. A 23-year-old Japanese woman, at 20 weeks of gestation, was referred to the Maternity and Perinatal Care Unit of Kyushu University Hospital because of fetal continuous bradycardia. B-mode scanning and dual M-mode echocardiography revealed that the fetus had complete atrioventricular block with endocardial cushion defect with a ventricular rate of 60 beats per minute. At 23 weeks of gestation, it was found that the fractional shortenings (FSs) in both ventricles and the ventricular rate had decreased, with an increase in pericardial effusion. Thus, we diagnosed the fetus as having cardiac failure. Transplacental digoxin treatment was started and continued for 10 weeks, after which fetal pericardial effusion, as well as FSs ameliorated. The pregnancy was interrupted by cesarean section at 33 weeks of gestation due to a decrease in FSs with an accumulation of fetal ascites. A 1780g female infant was delivered and a pacemaker was implanted surgically, immediately after birth. She is alive and well at the time of writing.

Adult↗
PubMed1992

The myocardial recovery mode after cold storage for transplantation with Collins' solution and cardioplegic solution. A functional and metabolic study in the rat heart.

Mechanisms and kinetics of the effects of the ionic composition of two different storage solutions, an intracellular type and an extracellular type, were analyzed by examining the myocardial functional and metabolic recovery processes during the early reperfusion periods after 3 hours of cold storage using an isolated perfused working rat heart model. The hearts were stored either in our own cardioplegic solution (group 1) or in Collins' solution (group 2) for 3 hours at 4 degrees C and were then reperfused. The electromechanical activity in group 1 was elevated, as indicated by a higher incidence of ventricular fibrillation at 5 minutes of reperfusion (group 1: 5/6; group 2: 0/5; p < 0.05). The coronary flow rate in group 2 was significantly lower, at least for the first 15 minutes after reperfusion, than that of group 1, suggesting the possible existence of vasoconstriction in group 2. Although myocardial oxygen uptake during this period was smaller in group 2, the recovery of myocardial high-energy phosphate levels was better and creatine kinase leakage was less in group 2. The recovery of aortic flow after 30 minutes of reperfusion was significantly better in group 2 (group 1, 59.1 +/- 5.8%; group 2, 71.7 +/- 6.0%; p < 0.01), although the early recovery was somewhat worse in group 2. These data suggest that the heart stored in an intracellular-type solution, compared with one stored in an extracellular-type solution, recovers in an electromechanically suppressed fashion during the early reperfusion phase, associated with a better metabolic recovery and a slower but larger functional recovery. The disadvantage of the intracellular-type solution, however, may be its effect on the increase of coronary vascular resistance during the early reperfusion period.

Animals↗
PubMed1992

Excellent durability of the Hancock porcine bioprosthesis in the tricuspid position. A sixteen-year follow-up study.

From February 1975 to August 1981, 23 consecutive patients underwent tricuspid valve replacement, which was either isolated (six patients) or combined with the replacement of other valves (17) by means of a standard, glutaraldehyde-preserved Hancock porcine bioprostheses. Patients' ages ranged from 9 to 53 (mean 36.2) years. The follow-up period ranged from 0.2 to 16.5 years (mean 9.1) and was complete in 100% of all cases. Structural valve failure of the tricuspid Hancock valve was noticed in two patients, a 9-year-old boy and a 13-year-old girl 3.4 and 16.5 years after implantation, respectively. The actuarial freedom rate from structural valve failure at 10 years was 94 +/- 6%. There were six tricuspid prosthesis-related events: structural valve failure in two and valve thrombosis, anticoagulant-related bleeding, prosthetic valve endocarditis, and periprosthetic leak in one each, respectively. The actuarial freedom from these events at 10 years was 78 +/- 10%. Five pairs of aortic/mitral-tricuspid Hancock valves were explanted simultaneously from the same patients after 8.1 to 13.9 (mean 11.4) years postoperatively. A gross examination showed no valve dysfunction in the explants from the tricuspid position, but degenerative changes with valve dysfunction in those from the mitral and aortic position were observed (none of five versus five of seven; p < 0.03). We concluded that the selection of a Hancock bioprosthesis in the tricuspid position is acceptable because of the low incidence of prosthesis-related complications and the excellent durability of more than 10 years.

Actuarial Analysis↗
PubMed1992

Collins' solution for cold storage of the heart for transplantation must be reversed with cardioplegic solution before reperfusion. A functional and metabolic study in the rat heart.

The following hypotheses were tested using an isolated perfused working rat heart model: (1) Collins' solution for cold storage of the heart is harmful for the heart during reperfusion; (2) a "reverse" of the intracellular-type Collins' solution with an extracellular-type cardioplegic solution before reperfusion is able to prevent this disadvantage of Collins' solution. The following two major groups (I and II) and five subgroups (-a to -e) in each group were prepared. In group I (reversed group); the hearts were initially stored in Collins' solution but were reversed by a 1-minute flush with cardioplegic solution followed by storage in cardioplegic solution for the last 1 to 180 minutes of the total 3-hour storage, that is, groups I-a (reversed for 1 minute), I-b (10 minutes), I-c (30 minutes), I-d (90 minutes), and I-e (180 minutes). In group II (nonreversed control group); the hearts were stored in Collins' solution throughout 3 hours and were also divided into five subgroups of groups II-a, II-b, II-c, II-d, and II-e in which only a 1-minute flush with Collins' solution was performed at the point corresponding to group I. The coronary flow in any of group II showed a marked decrease during the early reperfusion period. In group I, however, the coronary flow increased significantly in proportion to the duration of the reversing phase. The recovery of the aortic flow and the cardiac output in group I showed a bell-shaped pattern in relation to the duration of the reversing phase, reaching their peak values when reversed for 30 minutes (group I-c). The prolonged reverse (180 minutes) resulted in a deterioration of functional recovery associated with a poorer preservation of high-energy phosphates and a larger enzyme leakage. These results suggest that the beneficial effects of intracellular-type Collins' solution for cold storage of the heart were further improved by reversing Collins' solution with the extracellular-type cardioplegic solution for the last 30 minutes of the 3-hour cold storage because the disadvantageous vasoconstriction due to Collins' solution during reperfusion was successfully prevented by the replacement of intravascular and extravascular Collins' solution with cardioplegic solution before the reperfusion.

Animals↗
PubMed1992

[Spontaneous peripelvic extravasation after the operation of rectal cancer, treated by indwelling the ureteral stent: report of three cases].

Three cases of spontaneous peripelvic extravasation after the operation of rectal cancer are reported. In case 1, a 65-year-old female complained of left flank pain one month after high-anterior resection for rectal cancer. Drip infusion pyelography (DIP) and retrograde pyelography (RP) showed extravasation from the left renal pelvis. The ureteral stent was indwelled, and the extravasation showed remission. In case 2, a 55-year-old female complained of left lumbago 6 months after Miles' operation for rectal cancer. DIP showed extravasation from the left renal pelvis. The same findings were confirmed on the repeated DIP after 10 days. The ureteral stent was indwelled, and the extravasation was cured. In case 3, a 69-year-old male complained of left flank pain and left abdominal tumor 10 months after Miles' operation for rectal cancer. DIP and RP showed extravasation from the right renal pelvis, and computed tomographic (CT) scan showed urinoma formation. Drainage of the urinoma was performed and the ureteral stent was indwelled. The urinoma and the extravasation was cured. We emphasized the usefulness of indwelling the ureteral stent for the conservative management of spontaneous peripelvic extravasation caused by a malignant tumor, and a discussion of the relevant literature follows.

Aged↗
PubMed1992

[Successful surgical treatment by Konno aortoventriculoplasty in 2 cases of congenital aortic valvular stenosis].

Konno's aortoventriculoplasty was performed in two children aged 6 years and 10 years old with congenital aortic valvular stenosis. One had previous aortic valvotomy at 21 days of age. Preoperative peak systolic pressure gradients between the left ventricle and the aorta were 120 and 140 mmHg, respectively. The original diameter of the aortic valve ring were 12 mm and 16 mm and one had supra-annular aortic stenosis whose diameter was 7 mm. The 19 mm and 23 mm SJM prosthetic valves were inserted in the subcoronary position. The postoperative course was uneventful. Their ECG showed sinus rhythm with complete right bundle branch block. Both two patients made good recovery regarding clinical data and symptoms.

Aorta↗
PubMed1992

Significance of the concentrated red cell and albumin priming method with particular reference to anaphylatoxin generation.

Anaphylatoxins generated by cardiopulmonary bypass were observed in basic and clinical studies (n = 120 in the latter). In vitro immunoglobulin fractions denatured by oxygen bubbling produced C4a, C3a, and C5a, but albumin identically treated did not. Therefore concentrated red cells with albumin were used to prime homologous blood for clinical application during cardiopulmonary bypass. Complement levels were compared with type of oxygenator (bubble or membrane) and the ratio of primed homologous blood to circulating autologous blood volume. With the bubble oxygenator at a low ratio of homologous to autologous blood (arbitrarily defined as less than 20%), C3a levels during cardiopulmonary bypass tended to be lower in the concentrated red cells plus albumin priming group than in the ordinary priming group (p less than 0.1, at 60 and 90 minutes of cardiopulmonary bypass). C4a and C3a levels increased less after protamine administration with concentrated red cells plus albumin priming (p less than 0.05, p less than 0.01, respectively, 90 minutes after protamine) than with ordinary priming. Such changes in the membrane oxygenator group were less remarkable. Thus C3a levels were approximately the same in both oxygenator groups primed with concentrated red cells plus albumin. The higher the homologous to autologous ratio, the steeper the C4a and C3a increase from the beginning of cardiopulmonary bypass with the bubble oxygenator. This tendency was less remarkable in the membrane oxygenator group. Early postoperative pulmonary function was improved by concentrated red cells plus albumin priming, especially in the bubble oxygenator group. In conclusion, (1) oxygenator systems primed with concentrated red cells plus albumin produced less anaphylatoxin than those with homologous blood, especially with the bubble oxygenator, and (2) our clinical results support the importance of immunoglobulin denatured by oxygen bubbling in anaphylatoxin generation (by means of the classical pathway), as shown by our in vitro study.

Anaphylatoxins↗
PubMed1991

Analysis of arterial-venous blood concentration difference of drugs based on recirculatory theory with fast inverse Laplace transform (FILT).

An arterial and venous blood (or plasma) concentration difference of drugs across the lung of rats was evaluated based on the recirculatory concept. The recirculatory system is given by the combination of the transfer functions for the pulmonary and the systemic circulations and is described by a Laplace-transformed equation, i.e., an image equation. For the manipulation of the image equations, the fast inverse Laplace transform (FILT) was adopted and MULTI(FILT) was used for the simultaneous curve fitting to estimate the pharmacokinetic parameters in the recirculatory model. Metoprolol as a test drug and cephalexin as a control drug were infused respectively into the femoral vein for 30 min, and arterial and venous blood samples were collected simultaneously through the cannula at the femoral artery and at right atrium during and after the infusion. Exponential functions were assumed for the weight functions through both the pulmonary and systemic circulations. Results of the curve fitting showed that the single-pass extraction ratio through the pulmonary circulation (Ep) of metoprolol was about 0.2, whereas that of cephalexin was negligible. The mean transit times through the pulmonary circulation (tp) of metoprolol and cephalexin were both about 0.5 min, which is small. The single-pass extraction ratios through the systemic circulation (Es) of metoprolol and cephalexin were both about 0.1, and the mean transit times through the systemic circulation (ts) were 11.5 min and 8.2 min, respectively.

Animals↗
PubMed1991

Anomalous origin of the right pulmonary artery from the ascending aorta.

Five cases of anomalous origin of the right pulmonary artery from the ascending aorta were seen at our hospital. Patients 1 and 2 had an intact right pulmonary artery originating from a right posterior aspect (proximal form), and primary anastomosis of the right pulmonary artery and main pulmonary trunk was performed. Patients 3 and 4 showed a narrowing right pulmonary artery originating from near the base of the innominate artery (distal form). The stenotic right pulmonary artery was reconstructed with an 8-mm graft in patient 3, whereas patient 4 became inoperable because complete obstruction had developed in the right pulmonary artery during the 3 months that the patient was waiting to undergo operation. In patient 5, primary anastomosis was undertaken, but morphologically the anomalous origin was of the distal form, so the occurrence of stenosis in the reconstructed right pulmonary artery was a matter of concern. The morphological type was found to be related to the surgical options in this anomaly. Therefore, primary anastomosis was considered the best choice for a correction of the proximal form, whereas a graft interposition with a resection of the stenotic portion on the right pulmonary artery was deemed preferable in the distal form.

Aorta↗
PubMed1991

Preparation and characterization of a chimeric CD19 monoclonal antibody.

FMC63 is an IgG2a mouse monoclonal antibody belonging to the CD19 cluster. CD19 antibodies react with a 95kDa protein expressed by cells of the B lymphocyte lineage, from pre-B cells to mature B lymphocytes. CD19 antibodies have been suggested as candidates for immunological attack on leukaemic and lymphoma cells of the B lineage because the antigen is restricted to the B lineage. With the potential use of FMC63 in immunotherapy in mind, we have produced a mouse-human chimera in which the genes coding for the VDJ region of the heavy chain and the VJ region of the light chain derive from the FMC63 mouse hybridoma, while the C region genes code for human IgG1. The genes have been transfected back into a mouse myeloma line, which secretes low levels of immunoglobulin. (Ig). This Ig was purified and biotinylated in order to determine the specificity of the antibody. The chimeric antibody has a reaction profile concordant with the original FMC63 antibody, but has the properties of a human IgG1, including the ability to fix human complement. However, the antibody is not cytotoxic in vitro in the presence of complement or cells capable of mediating antibody-dependent cellular cytotoxicity. Possible reasons for this and ways of using the antibody are discussed.

Animals↗
PubMed1991

Relation between height and the maximum conduction velocity of the ulnar motor nerve in human subjects.

The maximum motor nerve conduction velocity of the right and left ulnar motor nerve was measured in more than 650 healthy medical students of both sexes. There was no side difference in the maximum conduction velocity. The shorter person has a statistically significant higher conduction velocity than the taller person. Comparison of students of both sexes showed a slightly higher conduction velocity in females. However, with regard to its relation to height, the conduction velocity was higher in males.

Adult↗
PubMed1991

Enhancement of immune response in Peyer's patch cells cultured with Bifidobacterium breve.

Bifidobacterium breve, included in fermented milk, was tested for adjuvanticity and mitogenicity using cells of mouse Peyer's patch, one of the gut-associated lymphoid tissues. Addition of B. breve enhanced antilipopolysaccharide antibody production in Peyer's patch cells and also anti-sheep red blood cell plaque-forming cells in Peyer's patch cells cultured with sheep red blood cells. Furthermore, addition of B. breve accelerated proliferation of Peyer's patch cells, particularly B cells. In BALB/c mice, enhancement of proliferation by B. breve was also found in Peyer's patch cells from nude mice and a B cell-enriched fraction, including both the B cell fraction and plastic-adherent cells. Enhancement was not found in the fraction in which Sephadex G10-adherent and carbonyl-iron phagocytic cells were excluded from Peyer's patch cells or in a pure B cell fraction in which plastic-adherent cells were excluded from the B cell-enriched fraction of Peyer's patch cells. The proliferation of B cells was enhanced when the supernatant of plastic-adherent cells cultured with B. breve was added. It is concluded that B. breve activated plastic-adherent cells and that these cells secreted a soluble factor that enhanced proliferation of B cells.

Animals↗
PubMed1991

[Recommendation for open heart surgery in infancy].

Progress in infant open-heart surgery last 10 years was reviewed mainly based on the surgical experiences in Fukuoka Children's Hospital. Recent advances and present problems in patient's care, cardiopulmonary bypass methods and cardioplegia were discussed. Low surgical mortality of 4.8% in 245 infant open-heart repairs between 1988 and 1990 in Fukuoka is highly suggestive of early primary repair for most of congenital heart diseases.

Cardiac Surgical Procedures↗
PubMed1991

[Diagnosis and surgical treatment of accessory mitral valve with associated congenital heart disease].

Accessory mitral valve (AcMV) is a rare cardiac anomaly that may possibly cause left ventricular outflow tract (LVOT) obstruction. Five patients who underwent surgical resection of AcMV were reported. All these patients had associated cardiac anomalies, which include transposition of great arteries (TGA) in two cases, ventricular septal defect (VSD) in one, double outlet right ventricle (DORV) in one and membranous septal aneurysm (MSA) in one. Age at operation ranged from 23 days to 22 months. In these cases preoperative pressure gradient across the LVOT ranged from 10 to 35 mmHg. Resection of AcMV was performed together with radical operation for associated anomalies in all the patients. Approach for resection of AcMV consisted of trans-ventricular septum method in 3 patients of VSD, DORV or MSA and trans-pulmonary artery method in 2 cases of TGA. There was no operative death. The postoperative pressure gradient across the LVOT ranged from 0 to 13 mmHg. Two dimensional echocardiography was essential for the accurate preoperative diagnosis of AcMV in 4 out of the 5 patients. The trans-ventricular septum method, when the large VSD was present, for resection of AcMV was found to be quite useful especially for neonates in order to obtain an excellent operative field, as compared with the conventional method.

Echocardiography↗
PubMed1990

Inhibition of mouse alpha/beta-interferon of the multiplication of alpha/beta-interferon-resistant Friend erythroleukemia cells cocultured with mouse hepatocytes.

Administration of alpha/beta-interferon (IFN) exerts a marked antitumor effect in DBA/2 mice given injections i.v. of large numbers of IFN-alpha/beta-resistant erythroleukemia cells (FLC). To investigate the possible mechanisms of FLC tumor inhibition in the liver of interferon-treated mice, we developed an in vitro model consisting of a coculture of IFN-alpha/beta-resistant 3Cl8 FLC and syngeneic mouse hepatocytes. Whereas IFN-alpha/beta did not inhibit the multiplication of 3Cl8 FLC cultivated alone, it effectively inhibited the multiplication of 3Cl8 FLC in coculture with hepatocytes. The inhibitory effect was directly proportional to the amount of IFN-alpha/beta added to the cocultures, and more than 90% inhibition of FLC multiplication was noted with 1.6 x 10(5) IU/ml of IFN-alpha/beta on Day 3 of coculture. When FLC were separated from the monolayer of hepatocytes by a pored membrane (0.4 microns), the inhibitory effect on FLC proliferation was unchanged, indicating that a soluble factor(s) released from IFN-treated hepatocytes was most important in the inhibition of FLC multiplication. An inhibitory activity of FLC multiplication was detected only in the conditioned medium of IFN-treated hepatocytes but not in the conditioned medium of control hepatocytes nor in extracts of IFN-treated or control hepatocytes. The inhibitory factor(s) in the conditioned medium of IFN-treated hepatocytes was retained by an ultrafiltration membrane (Mr cut off 10,000), and its activity was completely abrogated by trypsin digestion. Its stability to treatment with 1 M acetic acid as well as lack of correlation between the antiproliferative effect and the amount of L-arginine in the medium distinguished this factor(s) from liver arginase which was also found to be a potent inhibitor of FLC multiplication in vitro. The inhibitory factor(s) was also distinguishable in its biological activity from IFN gamma, interleukin 1 alpha and beta, and transforming growth factor beta 1 and beta 2. These results suggest the possibility that the inhibitory effect of IFN-alpha/beta on the development of 3Cl8 FLC in the livers of IFN-treated mice may be mediated by an IFN-induced inhibitor of FLC multiplication.

Animals↗
PubMed1990

Myocardial protection by retrograde cardioplegia in arterial switch operation.

Retrograde coronary sinus perfusion of cold cardioplegic solution was evaluated in infants undergoing an arterial switch operation for transposition of the great arteries. To assess myocardial injury during ischemia, hemodynamic measurements were conducted at weaning from cardiopulmonary bypass and a postoperative assay of creatine kinase isoenzyme MB was performed. In 22 infants with retrograde coronary sinus perfusion, the initial cardioplegic infusion was performed through the aortic root and additional infusion was repeated every 30 minutes by retrograde coronary sinus perfusion. The other 11 infants received additional solution by antegrade selective coronary artery perfusion. The aortic cross-clamp time in the retrograde coronary sinus perfusion group was significantly shorter than that in the antegrade selective coronary perfusion group (128 +/- 19 versus 143 +/- 21 minutes, p less than 0.05). There were no significant differences between the two groups in terms of postoperative hemodynamic variables and enzyme indexes. Eight neonates in the retrograde coronary sinus perfusion group also exhibited enzymatic and hemodynamic indexes similar to those of older infants. These results suggested that retroperfusion of cardioplegic solution was a safe and useful means of myocardial protection in infants and neonates because of the simplification of the operative procedure and the avoidance of traumatic injury to the coronary ostia.

Cardioplegic Solutions↗
PubMed1990

Studies on topical antiinflammatory agents. V. 17-(Alkylthio)- and methoxyalkanoates of corticosteroids.

As part of our search for new topical antiinflammatory agents, a series of corticosteroid 17-(alkylthio)- and methoxyalkanoate derivatives was prepared and tested for vasoconstrictive activities. Several compounds were proved to have activity superior or comparable to that of 9 alpha-fluoro-11 beta,21-dihydroxy-16 beta-methyl-17 alpha-valeryloxy-1,4-pregnadiene-3,20-dione (betamethasone 17-valerate, BV). Among these compounds, 21-chloro-11 beta-hydroxy-17 alpha-(methylthio)acetoxy-4-pregnene-3,20-dione (5Aa) was found to have the most potent activity, being more active than BV. The structure-activity relationships of the series revealed that introduction of a (methylthio)acetate function into the 17-position as well as the 21-position of corticosteroids was effective for enhancing the topical antiinflammatory activity.

Administration, Topical↗