Biomedical subjects

K Tatsuno

Publications and source records attributed to K Tatsuno.

At least 19 recordsLinked to original sources

PubMed1998

Morphometric analysis of atrioventricular septal defect with common valve orifice.

OBJECTIVES: We sought to analyze morphometric features of atrioventricular septal defect (AVSD) in autopsy specimens and to consider the developmental implications of obstruction in either ventricular outflow tract. BACKGROUND: Left ventricular outlet obstruction (LVO) is more prevalent in patients with Rastelli type A morphology. When tetralogy of Fallot (ToF) complicates this malformation, there is usually a free-floating superior bridging leaflet. The reasons for these associations are uncertain. METHODS: In 133 hearts with AVSD and common atrioventricular (AV) valve orifice, we measured the degrees of horizontal and anterior deviation of the great arteries from the AV valve, the diameters of the ventricular outlets and the great arteries and the degree of deficiency of the ventricular septum. RESULTS: In Rastelli type A morphology, the great arteries were deviated more leftward than in type C morphology (p < 0.01). Type A hearts also had a relatively small aorta, with a long and narrow subaortic tract. The presence of obstruction in either ventricular outlet was associated with a more oblique arrangement of the great arteries, with the pulmonary trunk being more leftward than in hearts without LVO (p < 0.01). In combination with ToF, the aorta was dextroposed and the pulmonary trunk was located more posteriorly (p < 0.01). No heart with type A morphology showed ToF (p < 0.01). CONCLUSIONS: The geometric arrangement of the great arteries correlated significantly with obstruction in either ventricular outflow tract and with the Rastelli subtypes. Malrotation of the developing outlet septum may be an embryologic factor producing obstruction, with horizontal deviation of the outlets also influencing the morphology of the superior bridging leaflet.

Aorta↗

PubMed1997

Properties of yeast expressed Aspergillus nidulans chitin synthase B which is essential for hyphal growth.

A complementary DNA of the Aspergillus nidulans chsB gene encoding chitin synthase, an essential gene for hyphal growth, was obtained by RT-PCR and expressed in Saccharomyces cerevisiae by using the GAL1 promoter in a multicopy plasmid. The biochemical characteristics of chitin synthase B (ChsB) expressed in S. cerevisiae were examined. The chitin synthase B produced in galactose medium showed zymogenicity due to activation by trypsin treatment and required Mg2+ ion to exert maximal activity. It was competitively inhibited by polyoxin D. The Ki value of the inhibitor was 10 microM, and the K(m) for the substrate was 1.6 mM. The activity was enhanced by the addition of N-acetylglucosamine. The optimal pH is 7.5 when Mg2+ is used. These characteristics are the same as those of other chitin synthases.

Aspergillus nidulans↗

PubMed1997

[Open heart surgery without blood transfusion for complete atrioventricular septal defect associated with tetralogy of Fallot].

Open heart surgery without blood transfusion was successfully performed in two patients with complete atrioventricular septal defect associated with tetralogy of Fallot. The postoperative hemodynamics and respiratory status were uneventful in both patients (central venous pressure after ICU admission: 13.7 cmH2O and 11.5 cmH2O, intubation time after surgery: 9 hours and 11 hours). Autologous blood donation immediately after induction of anesthesia and minimization of bypass circuit were effective methods for open heart surgery without blood transfusion, particularly in cyanotic patients requiring prolonged cardiopulmonary bypass for intracardiac repair.

Blood Transfusion, Autologous↗

PubMed1997

[Open heart surgery without homologous blood transfusion for tetralogy of Fallot--use of hydroxyethyl starch diminishes the necessity of protein transfusion].

To avoid any blood or protein transfusions, we employed 6% hydroxyethyl starch in 0.9% saline (saline HES) during cardiopulmonary bypass (CPB) for intracardiac repair in 24 consecutive patients with Tetralogy of Fallot (TF). The postoperative course has been satisfactory (central venous pressure 9.5 +/- 1.2 cmH2O, duration of intubation after surgery 4.4 +/- 1.5 hours), and all patients but one did not require transfusion therapy during their hospital stay. We conclude that intracardiac repair without transfusions is feasible in almost all patients with TF, when substituting saline HES for blood or proteins.

Blood Proteins↗

PubMed1996

Inhibition of hepatitis-B-virus core promoter by p53: implications for carcinogenesis in hepatocytes.

The incidence of hepatocellular carcinoma (HCC) is particularly high in regions of Asia and sub-Saharan Africa where rates of infection with human hepatitis-B virus (HBV) and aflatoxin-B1 contamination of food are high. In HCC tumors occurring in inhabitants of these regions, a G-to-T mutation frequently occurs at position 249 of the tumor-suppressor gene p53. This suggests that HBV and p53 mutation may collaborate in the carcinogenic process in liver. We have examined the effect of the HBV protein HBX in HCC lines with exogenous wild-type p53 or mutated p53 on transactivation of 2 different reporter genes. Transfection of HCC lines with wild-type p53 and a reporter with the promoter from the p53-responsive gene WAF1/p21 resulted in a high level of expression, as expected. When cells were co-transfected with a reporter gene driven by the HBV core promoter and with the HBX gene, expression was enhanced in the Hep 3B, HLE, PLC/PRF/5 and HuH 7 lines, but not in the HuH 1 line. Co-transfection of the reporter with a plasmid containing wild-type p53 resulted in significant inhibition of the HBV core promoter in all of the lines, whereas the mutated p53 gene had no effect. Our results indicate that wild-type p53 can inhibit transcription from the HBV core promoter. In similar experiments, both HBX and p53 were co-transfected into HCC lines with the WAF1/p2l reporter gene. HBX inhibited p53-induced expression in 4 of the 6 lines (Hep 3B, HuH 1, HuH 7 and HLE), there was no effect in one line (HLF), and enhancement was evident in PLC/PRF/5. Our results indicate that inhibition of p53 transcriptional activity by HBX does occur in HCC, but is highly cell-context-dependent. Inhibition of transcription from the HBV core promoter by wild-type p53 appears to be more universal, and may represent a mechanism by which wild-type p53 can protect against the carcinogenic process in liver.

Carcinoma, Hepatocellular↗

PubMed1996

[Axillo-iliac bypass grafting for reoperation of graft stenosis after aortic arch reconstruction of type B interruption of the aortic arch: two cases report].

Right axillo-iliac bypass grafting was performed in two females (10 and 14 years old) who had stenosis or obstruction of grafts after reconstruction of the aortic arch in type B interruption. The initial bypass operations were carried out at the age of 5 months and 5 years, with the use of a 5-mm EPTFE graft and a 10-mm Dacron graft. Nine years later, the EPTFE graft was completely obstructed, and the Dacron bypass has stenosis, kink and calcification. To minimize surgical invasion, axillo-iliac extra-anatomical bypass was employed in both patients. 8-mm or 10-mm Hemashield grafts were implanted between the right axillar artery and the right common iliac artery through the intrapleural-preperitoneal route, and favourable results were obtained in both patients. The axillo-iliac bypass is considered to be a beneficial conservative method of reoperation for stenosis after graft reconstruction of the aortic arch in the younger age patients.

Adolescent↗

PubMed1996

[Open heart surgery with bloodless priming for cyanotic congenital heart diseases--the role of autologous blood donation after induction of anesthesia].

In 50 patients with cyanotic congenital heart diseases, open heart surgery was conducted with bloodless priming from January 1994 to August 1995. Surgical procedures included the Rastelli procedure (n = 14), the modified Fontan procedure (n = 10), and intracardiac repair of TOF (n = 26). The non-transfusion rate from January 1994 to August 1994 was 17% (1/6) in the Rastelli group, 67% (2/3) in the Fontan group, and 67% (8/12) in the TOF group. Autologous blood donation immediately after induction of anesthesia was carried out from September 1994 because post-operative hemorrhage and severe hemolysis of residual blood of the pump required conventional blood transfusions up to August. Autologous blood of 12 +/- 2 ml/kg could be collected, and the non-transfusion rate from September 1994 to August 1995 was increased to 75% (6/8) in the Rastelli group, 86% (6/7) in the Fontan group, and 93% (13/14) in the TOF group. There were no complications due to asanguineous extracorporeal circulation or autologous blood donation, and the post-operative hemodynamic and respiratory status were uneventful in almost all cases. We conclude that open heart surgery without blood transfusion is feasible in more than 70-80% patients who undergo the Rastelli procedure, the modified Fontan procedure or intracardiac repair of TOF. Autologous blood donation after induction of anesthesia proved to be highly effective method for reducing conventional blood transfusion.

Blood Transfusion, Autologous↗

PubMed1995

Does hypoplasia of one pulmonary artery preclude a definitive repair in pulmonary atresia, intact ventricular septum, and hypoplastic right ventricle?

Twins with pulmonary atresia, intact ventricular septum, and hypoplastic right ventricle associated with underdeveloped and discontinuous left pulmonary artery are described. Operations to connect the left pulmonary artery to the main pulmonary trunk, with subsequent biventricular repair assisted by bidirectional cavopulmonary anastomosis and atrial fenestration were performed. Follow-up catheterization proved spontaneous closure of the fenestration in one patient. Both patients have been in a satisfactory condition for 3 years since operation.

Anastomosis, Surgical↗

PubMed1995

[Open heart surgery with bloodless priming for ventricular septal defect and pulmonary hypertension].

In 17 patients with ventricular septal defect and pulmonary hypertension (VSD, PH) weighing 5.2 kg to 9.5 kg, open heart surgery was conducted with bloodless priming (total priming volume: 370-470 ml). None of the patients required blood transfusion during their hospital stay. The post-operative respiratory status was excellent in all cases with duration of intubation being 6 +/- 3 hours. While 12 patients weighing over 6.6 kg maintained individual constant hematocrit (Hct) values during cardiopulmonary bypass (CPB), all 5 patients weighing under 6.1 kg showed significant decrease during rewarming (17 +/- 2% after initiation of CPB to 14 +/- 2% during rewarming). The lowest Hct value was 12% during rewarming in 6.0 kg infant. The pre-operative circulating blood volume (CBV) was calculated retrospectively from the priming volume, the Hct value after anesthetic induction and the Hct value after initiation of CPB. The relationship, CBV (ml) = body weight (kg) x 72-13 (r = 0.85, p < 0.01) was derived. Using this equation, we calculated the predicted Hct level after initiation of CPB using the 370 ml bypass circuit in 43 VSD PH patients weighing 3.4 kg-5.9 kg. The Hct values were 17 +/- 2% in 13 patients weighing over 5 kg with 12 (91 percent) above 15%, and 13 +/- 2% in 30 patients weighing under 4 kg with 3 (11 percent) above 15%. Hct levels of 34%-36% before CPB were essential in patients weighing 4.0 kg-4.9 kg for the Hct level after initiation of CPB to exceed 15%.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Loss, Surgical↗

PubMed1995

[Valvuloannuloplasty for atrioventricular valvular regurgitation in complicated cyanotic cardiac anomalies].

Valvuloannuloplasty for atrioventricular (AV) valvular regurgitation was performed in 13 patients with univentricular AV connection and double outlet right ventricle. The suturing-up of free margins of the anterior and posterior common leaflets, which divides the common orifice into two parts, was performed in 4 children with quadricuspid or quintacuspid common AV valve and effectively reduced the regurgitation. The semicircular annuloplasty with a thin GORE-TEX graft was carried out in two patients having tricuspid AV valve, and a favourable result was obtained. In bicuspid AV valvular regurgitation, two patients received the suturing-up of free margins of prolapsed leaflets, and the results were satisfactory. From these results we consider that the semicircular annuloplasty for dilated tricuspid AV valve and the suturing-up of free margins of dilated or prolapsing leaflets in quadricuspid or quintacuspid and bicuspid AV valves are the recommendable procedures. If more than mild AV valvular regurgitation remained after these valvuloplasties, the Kay's and/or DeVega's annuloplasties should be added for eliminating the regurgitation.

Adolescent↗

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

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

Valvuloplasty for common atrioventricular valve regurgitation in cyanotic heart diseases.

Valvuloplasty for common atrioventricular valvular regurgitation and bidirectional cavopulmonary shunt were successfully performed in 3 children with univentricular heart and double-outlet right ventricle. The free margins of opposite leaflets of the common atrioventricular valve were sutured together to restore coaptation of the leaflets, and Kay-Reed's or DeVega's annuloplasty was carried out. Postoperative examinations revealed significant reduction of atrioventricular valve regurgitation and improvement of general condition in all patients.

Child↗

PubMed1994

[Valvulo-annuloplasty for atrioventricular valvular regurgitation in univentricular heart and double outlet right ventricle].

Valvulo-annuloplasty for atrioventricular (AV) valvular regurgitation was performed in 10 patients with univentricular heart and double outlet right ventricle. Kay annuloplasty alone was employed in three patients with a quadricuspid or tricuspid common AV valve. Two of them died after the operation and the remaining one is waiting for reoperation because of recurrence of severe AV valve regurgitation. The suturing-up of free margins of the anterior and posterior common leaflets was performed in 3 children with quadricuspid common AV valve and effectively reduced the regurgitation. The semicircular annuloplasty with a thin Gore-tex graft or the suturing-up of floppy leaflets combined with plasty of the chordae and papillary muscle was carried out in two patients having tricuspid AV valve, and a favourable result was obtained in the semicircular annuloplasty. In mitral AV valvular regurgitation, two patients received the suturing-up of free margins of prolapsed leaflets, and the results were satisfactory. From these results we consider that the semicircular annuloplasty for dilated tricuspid AV valve and the suturing-up of free margins of dilated or floppy leaflets in quadricuspid and bicuspid AV valves are the recommendable procedures. If more than mild AV valvular regurgitation remains after these valvuloplasties, the Kay and/or DeVega annuloplasties should be added for eliminating the regurgitation.

Adolescent↗

PubMed1994

[Clinical study of continuous warm blood cardioplegia with normothermic cardiopulmonary bypass in coronary artery bypass surgery].

This study was undertaken to determine whether continuous warm blood cardioplegia (CWBCP) could be acceptable as an alternative method for myocardial preservation in cardiac surgery. Between December 1991 and June 1993, 100 consecutive patients underwent coronary artery bypass surgery. Four patients who received terminal warm blood cardioplegia were excluded in this study. Fourty-eight patients (Group C) served as historical controls, and fourty-eight patients (Group W) from October 1992 to June 1993 served as a prospective, consecutive cohort for statistical comparison. Two groups varied in the types of myocardial protection and cardiopulmonary bypass (CPB) used: intermittent cold blood cardioplegia and moderate hypothermic CPB were used in Group C and CWBCP and normothermic CPB in Group W. The groups had similar number of bypass grafting, aortic cross-clamping time and CPB time. No patients was died. The prevalence of intraoperative cerebral infarction was equal in both groups (4.2%). The incidence of spontaneous defibrillation at cross-clamp removal was higher in Group W (85.4% versus 8.3%; p < 0.01). Less inotrope (dopamine) at 6 hours after operation was required in Group W (3.27 +/- 2.48 versus 4.78 +/- 2.99 micrograms/kg/min; p < 0.01). The intraoperative urgent use of the intraaortic balloon pump was noticeably less prevalent in Group W (0% versus 12.5%; p < 0.05). Group W patients were more likely to be hemodynamically stable after CPB discontinuing. Serum potassium levels during CPB was higher in Group W (max. 5.67 +/- 0.96 versus 4.39 +/- 0.50 mEq/l), so excessive potassium was eliminated using extracorporeal ultrafiltration. The major drawback of CWBCP was that continuous coronary perfusate occasionally obscured anastomosis site.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1993

Valve morphology in complete atrioventricular septal defect: variability relevant to operation.

The remodeling of the atrioventricular valves in patients with complete atrioventricular septal defects is the crucial part of surgical repair. Variability in valve morphology is an important factor. This study evaluates the variability in morphology of the anterior and posterior leaflets in 30 heart specimens. All hearts had an anterior bridging leaflet: Rastelli type A in 12, type B in 2, and type C in 16. The posterior leaflet revealed four morphologic patterns: a right- and left-sided posterior leaflet, both inserting directly onto the crest of the ventricular septum (5 hearts); a common posterior leaflet attached to the septal crest by a membrane (2 hearts); a common posterior leaflet attached to the septal crest by multiple chordae (13 hearts); and a virtually free-floating posterior leaflet (11 hearts). The categorization is surgically relevant in making a distinction between hearts with and without an interventricular communication underneath the posterior leaflet. Surgically relevant variations occurred also in arrangement and positioning of chordae originating from the right septal side. There was no relationship between the Rastelli classification of the anterior leaflet and that of the posterior leaflet. The variability in morphology of the posterior leaflet and its attachments to the ventricular septum appear equally crucial for successful repair as that of the anterior leaflet.

Chordae Tendineae↗

PubMed1993

Cytokines induce uridine phosphorylase in mouse colon 26 carcinoma cells and make the cells more susceptible to 5'-deoxy-5-fluorouridine.

The antiproliferative activity of 5-fluorouracil (5-FUra) and 5'-deoxy-5-fluorouridine (5'-dFUrd), used in combination with typical cytokines and growth factors, was investigated in mouse colon 26 carcinoma cells. Tumor necrosis factor alpha (TNF alpha), interleukin-1 alpha (IL-1 alpha), and interferon gamma (IFN gamma) at low doses showing < 50% inhibition of cell growth by themselves enhanced the susceptibility of the cells to the activity of 5'-dFUrd. In particular, a mixture of these cytokines greatly enhanced the activity of 5'-dFUrd and 5-FUra by up to 12.4- and 2.7-fold, respectively, whereas the activity of other cytostatics was only slightly changed (< 1.5-fold). Basic fibroblast growth factor also increased the susceptibility, but only to 5'-dFUrd. This preferential enhancement of the activity of 5'-dFUrd would be due to induction by the cytokines of uridine phosphorylase (Urd Pase), by which 5'-dFUrd is converted to 5-FUra. TNF alpha, IL-1 alpha, IFN gamma, and a mixture of these factors increased the enzyme activity by up to 3.7-fold in colon 26 cells. Consequently, the anabolism of 5'-dFUrd to fluoronucleotides and the incorporation of 5-FUra into RNA in colon 26 cells were increased by TNF alpha treatment. In addition, the increase by the cytokine mixture in the susceptibility to 5'-dFUrd was abolished by an inhibitor of Urd Pase, 2,2'-anhydro-5-ethyluridine. These results indicate that induction of Urd Pase activity by cytokines is a critical event that increases the susceptibility to 5'-dFUrd.

Animals↗

PubMed1993

Atypical form of atrioventricular septal defect without left axis deviation: relation between morphology and unusual QRS axis.

OBJECTIVE: To clarify the morphological features relating to an intermediate axis or a right axis deviation in atrioventricular septal defect (AVSD). SUBJECTS: 135 patients with typical AVSD and with nine patients with atypical AVSD, characterised by a well formed atrial septum, a milder downward displacement of the atrioventricular valves, and a shorter length of the ostium primum defect. MAIN OUTCOME MEASURES: Relation between morphology and electrocardiographic and vectorcardiographic findings; prevalence of Down's syndrome and of other cardiac anomalies. RESULTS: All nine patients with atypical AVSD had an unusual mean frontal QRS axis compared with six of the 135 patients (4%) with typical AVSD (p < 0.01). All eight patients who underwent the vector analyses showed atypical movement of the QRS loop--that is, an initial left inferior movement in the frontal loop (eight patients) and counter-clockwise rotation in the sagittal loop (seven). The corresponding values for 119 patients with typical AVSD were 20 and 22 patients (p < 0.01). Seven patients with atypical AVSD (78%) and 55 (41%) with typical AVSD had Down's syndrome (p < 0.05). None of the twenty one patients with additional cardiac anomalies had atypical AVSD, an unusual QRS axis, or unusual movement in the QRS loop. CONCLUSIONS: The atypical morphology, supposedly related to the degree of posteroinferior displacement of the conduction system, was one of the causes of unusual movement of the QRS loop in AVSD.

Adolescent↗