Biomedical subjects

H Orita

Publications and source records attributed to H Orita.

At least 37 records · Page 2Linked to original sources

PubMed1995

Absorption cytometric DNA analysis of sections of gastric carcinomas and a comparison with cytofluorometry of single-cell suspensions and flow cytometry.

Measurements were made of cellular deoxyribonucleic acid (DNA) content in paraffin-embedded materials from 44 gastric carcinomas, using three different methods; static cytometric light absorbance technique using tissue sections (SCM-abs), static cytometric fluorescence technique using single-cell suspensions (SCM-flu), and flow cytometry (FCM). The DNA ploidy determined by SCM-abs was grouped into low or high ploidy according to dispersion on the DNA histogram, and the DNA ploidy determined by SCM-flu and FCM was grouped into diploidy or aneuploidy, according to the peak DNA value. Accord between SCM-abs and SCM-flu or between SCM-abs and FCM was confirmed when low ploidy by SCM-abs showed diploidy by SCM-flu or FCM and high ploidy by SCM-abs showed aneuploidy by SCM-flu or FCM. An incomplete but good accord of DNA ploidy was obtained with these methods.

Absorption↗

PubMed1995

In vitro evaluation of nicorandil, diltiazem, and prostaglandin E1 on hypothermic injury to immature myocytes.

The purpose of the present study was to evaluate the functional and biochemical effects of nicorandil (NRD), diltiazem (DTZ), or prostaglandin E1 (PGE) on cardiac myocytes incubated under hypothermic conditions. Cardiac myocytes were isolated from neonatal rat ventricles and cultured for 4 days with MCDB 107 medium. Myocytes (12.5 x 10(5) myocytes/flask) were then incubated at 4 degrees C for 24 hr in media containing various concentrations of NRD, DTZ, or PGE. After hypothermic incubation, creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) were measured. The myocytes were then cultured for an additional 24 hr at 37 degrees C to evaluate the recovery of myocyte beating rate. In the nicorandil groups, 10(-4) M NRD showed significantly increased beating rate recovery compared to control (44.2% vs 24.6%, respectively, as a percentage of control, i.e., beating rate prior to hypothermic incubation). Treatment with 10(-6) M diltiazem showed no beneficial effects (10(-6) M: 25.2%; control: 29.8%); however, beating was not observed at 10(-4) or 10(-5) M. There were no significant changes among the PGE groups. The release of CPK and LDH was significantly suppressed with 10(-4) M NRD (10(-4) M: 24.1, 257.2 MIU/flask; control: 125.4, 459.5 mIU/flask, respectively). However, 10(-4) M DTZ showed significantly increased CPK and LDH levels compared to the control (10(-4) M: 203.3, 883.4 mIU/flask; control: 112.3, 457.4 mIU/flask, respectively). There were no significant differences for CPK and LDH levels among the PGE groups. In conclusion, nicorandil has protective characteristics for immature myocytes that may be suitable for cardiac preservation in the neonatal period.

Alprostadil↗

PubMed1995

Long-term hypothermic preservation of cardiac myocytes isolated from the neonatal rat ventricle: a comparison of various crystalloid solutions.

In this study, the functional and biochemical effects of crystalloid solutions on immature cardiac myocytes incubated under hypothermic conditions were evaluated. Cardiac myocytes were isolated from neonatal rat ventricles and cultured for 4 days, following which 12.5 x 10(5) myocytes per flask were incubated at 4 degrees C for 3, 6, 12, and 18 h in five types of crystalloid solutions: lactated Ringer's (LR), St. Thomas' Hospital (ST), University of Wisconsin (UW), 5% glucose-based potassium (GK), and normal saline (NS). The levels of creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) in the solutions were measured after each hypothermic incubation, following which the myocytes were cultured for an additional 24 h at 37 degrees C to evaluate the recovery of the myocyte beating rate. In the LR, UW, and NS groups, the recovery ratios of the myocyte beating rate were over 95% of the control (the beating rate prior to hypothermic incubation) at 3 h, but decreased to 20.3, 15.1, and 0%, respectively, at 18 h. The ST and GK groups had significantly lower recovery ratios than the other three groups (72.9% and 63.4%, respectively) at 3 h. The release of CPK and LDH in the LR, UW, and NS groups was significantly suppressed compared to the ST and GK groups, with the greatest suppression observed in the LR group. Moreover, the ST and GK groups had the highest CPK and LDH levels, respectively. Thus, LR solution had the least cytotoxic effects, indicating that it could be the most suitable basic solution of the various cardioplegic or preservation solutions during the neonatal period.

Adenosine↗

PubMed1995

Hypoxic injury of immature cardiac myocytes under various hypothermic conditions using an in vitro cell-culture model.

The purpose of this study was to evaluate the functional and biochemical effects in immature cardiac myocytes under hypoxic and hypothermic conditions. Cardiac myocytes were isolated from neonatal rat ventricles and cultured for 4 days, after which 12.5 x 10(5) myocytes/flask were incubated under 3% hypoxic conditions at 4 degrees C, 10 degrees C, 15 degrees C, 20 degrees C, 25 degrees C, and 37 degrees C for 6, 12, and 24 h. After each hypoxic incubation, creatine kinase (CK) and lactate dehydrogenase (LDH) were measured in the incubation medium. The myocytes were then cultured for an additional 24 h at 37 degrees C to evaluate the recovery of the myocyte beating rate. In the 4 degrees C and 37 degrees C groups, the myocyte beating rate recovery markedly decreased with increasing incubation times from 78.1% and 97.2% at 6 h to 0.0% and 38.4% of the control, which was the beating rate prior to hypoxic incubation, at 24 h, respectively. However, in the 10 degrees C, 15 degrees C, and 25 degrees C groups, this value decreased significantly only at 24 h. In the 20 degrees C group, beating rate completely recovered in 24 h. A marked increase was found in the release of CK and LDH in the 4 degrees C group from 28.5 mIU/flask and 232.9 mIU/flask at 6 h to 83.7 mIU/flask and 640.7 mIU/flask at 24 h, respectively. However, in the 25 degrees C and 37 degrees C groups, this release was significantly increased only at 24 h.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1995

[Effects of combined aprotinin and prostagrandin E1 therapy on aortic arch replacement].

This study was undertaken to compare the effects of combined aprotinin and prostaglandin E1 therapy on aortic arch replacement. Twenty patients were divided into 2 groups with (group A; n = 10) or without (group B; n = 10) the treatment (200 KIU of aprotinin and 0.01-0.02 microgram/kg/min of prostaglandin E1 during cardiopulmonary bypass (CPB) and the first postoperative day. Preoperative evaluation of respiratory function and all parameters related to CPB procedure were revealed to be equal between the groups. Postoperative A-a DO2 and respiratory index (RI) as functional parameters of oxygenation capacity, dosage of dopamine were monitored at 0, 3, 6, 12, 18 and 24 hr after termination of CPB and at extubation period. Serum creatinine, platelet numbers and blood coagulation function (PT, APTT) were also assayed postoperatively. The recovery of respiratory and cardiac function were superior in group A with treatment, but renal and blood coagulation function showed no difference in the groups. We suggest the combined therapy with aprotinin and prostaglandin E1 for aortic arch replacement may emerge as a valuable treatment to save postoperative respiratory and cardiac function.

Alprostadil↗

PubMed1995

[Valve repair or valvulectomy without replacement for infective endocarditis: a report of 11 cases].

Recently advances in early diagnosis of infective endocarditis (IE) by echocardiography provide for IE as a target disorder for valve repair. Valvulectomy without replacement might be still better operation of choice for some cases of intractable right-sided endocarditis. For our experience in 11 cases of valve repair or valvulectomy without replacement for IE, actuarial survival and reoperation-free rate at 6.8 years of mean follow-up after surgery was 81.8% and 90.9%. Persistent infection and intraoperative evaluation of the residual regurgitation was the point for postoperative management after these procedures. Although an elaborative valve repair should be applied for right-sided endocarditis, total pulmonary valvulectomy or regional tricuspid valvulectomy without prosthesis was available for destructive endocarditis.

Adolescent↗

PubMed1995

[A case of pentalogy of Cantrell with tetralogy of Fallot and left ventricular diverticulum].

We report a successful repair of tetralogy of Fallot and left ventricular diverticulum associated with pentaology of Cantrell. The repair consisted of partial infundibular septectomy, closure of ventricular septum, reconstruction of right ventricular outlet using monocuspid transjunctional patch, and resection of left ventricular diverticulum. The infundibulum was extremely elongated, caused by ventricular dextroversion, and the hypoplasia of pulmonary trunk was absent. Therefore, transjunctional patch was longer, even after infundibular septectomy. This report discuss the pathogenesis of these cardiac anomalies and surgical imlication.

Abnormalities, Multiple↗

PubMed1995

[Rastelli operation for congenital heart disease complicated with peripheral pulmonary artery stenosis].

Peripheral pulmonary artery stenosis following the occlusion of ductus arteriosus is not rare in patients with pulmonary atresia. It is also seen after the creation of Blalock-Taussig shunt for various types of cyanotic congenital heart disease. Although pericardial patch enlargement for the pulmonary artery stenosis has been done at corrective surgery, the results were unsatisfactory because of restenosis. So, we proposed and performed a new method of pulmonary artery plasty using large rectangular heterogeneous pericardium, by which pulmonary artery could be widely enlarged from the pulmonary trunk to periphery of the stenosis. A 3-year-old female (case 1) was diagnosed with pulmonary atresia, ventricular septal defect, patent ductus arteriosus and coronary anomaly associated with left pulmonary artery stenosis. She previously received left Blalock-Taussig shunt. Another patient was a 4-year-old male (case 2) diagnosed with double-outlet right ventricle, pulmonary stenosis and patent ductus arteriosus. He also received right Blalock-Taussig shunt and had left pulmonary artery stenosis. Both patients received Rastelli operation with pulmonary artery plasty simultaneously. Rastelli operation was performed using composite graft consisted of valved heterogeneous pericardial roll and knitted Dacron graft. Post operative courses were uneventful and they were doing well one year after operation. We consider that the pulmonary artery plasty with rectangular heterogeneous pericardial patch is an effective surgical procedure to avoid restenosis compared with conventional pericardial patch enlargement or balloon pulmonary artery plasty.

Blood Vessel Prosthesis↗

PubMed1995

[A case report of infective endocarditis complicated with Klippel-Trenaunay-Weber syndrome].

We reported an experience of successful aortic valve replacement due to active infective endocarditis complicated with Klippel-Trenaunay-Weber (KTW) syndrome which was characterized by limb hypertrophy, hemangioma, arteriovenous fistula and varicose veins. A 27-year-old man was admitted to our hospital because of severe dyspnea and high grade fever. Echocardiogram revealed severe aortic regurgitation and destruction of aortic valve due to active infective endocarditis. We performed aortic valve replacement and patch closure of annular abscess. As to vascular malformation of lower limb including arteriovenous fistula and varicose veins, surgical treatment was not undergone to avoid postoperative limb dysfunction. Although the origin of infective endocarditis was uncertain, the patient had peripheral vascular malformations. It was postulated that valvular endocardial injury might be occurred by cardiac volume overload due to arteriovenous fistula. The patients with KTW syndrome should be followed under careful observation since infective endocarditis may be one of the complications of the syndrome.

Adult↗

PubMed1995

[Limited skin incision and partial median sternotomy for the repair of atrial septal defects in children].

Eight patients underwent the repair of atrial septal defect using the limited skin incision and partial median sternotomy. The average length of skin incision was 55% of the longitudinal size of the sternum. Our approach did not prolong the operation time and decreased the bloodloss. Moreover, postoperative events, such as hematoma, sternal instability, and wound infection, were not observed, and the cosmetic result was excellent. We think this method is safe and effective especially for children with atrial septal defect.

Child↗

PubMed1995

[Antegrade or retrograde blood cardioplegic method: comparison of postsurgical right ventricular function and conduction disturbances].

This study was undertaken to compare postsurgical right ventricular function and the occurrence of conduction disturbances after employing cold blood antegrade or retrograde cardioplegia during open heart surgery. Thirty-four patients were divided into AC (antegrade) and RC (retrograde) groups for the difference of route for delivery of cardioplegic solutions. Preoperative evaluation of cardiac and respiratory function revealed to be equal characteristics between the groups. Postoperatively, A-aDO2 and respiratory index (RI) as functional parameters of oxygenation capacity, LVSWI, RVSWI, dosage of dopamine and conduction disturbances were monitored at 0, 3, 6, 12 hours after termination of cardiopulmonary bypass and at extubation period. Although the recovery of respiratory function and left ventricular function were similar in both groups, temporal suppression of right ventricular function was indicated in RC group during early period after surgery, and then recovered to the same values of AC group within 3 hours. In RC group, several type of conduction disturbances were detected in 28 per cent of patients. But none of the persistent conduction disturbances were remained in all patients. We suggest retrograde coronary sinus perfusion may emerge as a valuable alternative to antegrade methods for delivery of cardioplegia.

Blood↗

PubMed1995

[Comparison of postsurgical respiratory function employing either cold blood or crystalloid cardioplegia during open heart surgery].

This study was undertaken to compare postsurgical respiratory function after employing cold blood or cold crystalloid cardioplegia during open heart surgery. Fourty patients were divided into two groups for the difference of the cardioplegic solutions. Preoperatively, left ventricular stroke work index (LVSWI) and respiratory function test was evaluated. Postoperatively, A-a DO2 and respiratory index (RI) as functional parameters of oxygenation capacity, LVSWI and dosage of dopamine were monitored at 3, 6, 12, 18, 24 hours after cardiopulmonary bypass and at extubation period. The recovery of respiratory function and cardiac performance were superior in blood cardioplegia with a less accumulation of water in the pulmonary interstitium as a result of hemodilution effect.

Blood↗

PubMed1995

[A case report on a reconstructive operation of a traumatic tricuspid regurgitation with a congenital defect of the left pericardium].

We reported a successful tricuspid valve replacement in a 58-years old man, who had easy fatiguability after 14 years of a blunt chest trauma. The preoperative examination revealed a marked cardiomegaly with deformation of both ventricles and grade 4 tricuspid regurgitation caused by the prolapse of the anterior leaflet. The operative inspection revealed a left pericardial defect with a diameter of 10 cm and a torn anterior papillary muscle. Since a usual plastic procedure did not improve the regurgitation, a Carpentier-Edward bioprosthetic valve was implanted in the supra annular position. Atrioventricular conduction was preserved. The tricuspid valve was not resected to preserve the ventricular function. The patient recovered his own activity.

Heart Injuries↗

PubMed1995

[A case of tricuspid atresia treated with fenestrated total cavopulmonary connection at late infantile stage].

A one-year-old girl with tricuspid atresia (TA) underwent fenestrated totalcavopulmonary connection (TCPC) after pulmonary artery banding. Under cardiopulmonary bypass, an fenestrated intraatrial cavocaval channel was constructed with a prosthetic graft of polytrafluorothylene. The SVC was transsected and each end of SVC was anastomosed to the pulmonary artery in a end-to-side fashion. She did not need "high CVP management" nor "low HR management" in the post operative course. We suggest that fenestrated TCPC may be indicated for the patients of TA at late infantile stage.

Blood Vessel Prosthesis↗

PubMed1994

Role of intraoperative assessment of lymph node metastasis and serosal invasion in patients with gastric cancer.

The clinical diagnoses of nodal status (N) and tumor invasion (T) were performed intraoperatively during 1499 consecutive operations for gastric carcinoma and compared with subsequent pathologic diagnoses. An accurate macroscopic diagnosis of N stage was difficult; overall accuracy was only 56.6%. Intraoperative assessment of T stage (particularly of serosal invasion) was correct for 93.2% of early stages of the disease with invasion confined to the mucosa or submucosa (pT1) when the pathologist assessed the T stage in the resected specimen, for 95.6% of advanced tumors invading the serosa (pT3), but for tumors of an intermediate stage with invasion involving the muscularis propria or the subserosa (pT2) in only 41.9% of cases. Macroscopic overestimation occurred in 58.1% of cases with pT2 tumors, which were characterized by carcinomas in the upper third of the stomach, tumors larger than 5 cm, carcinomas of the ulcerating type, differentiated adenocarcinomas, tumors invading the subserosa, and those accompanied by lymph node metastasis or liver metastasis. The overestimated group had a significantly poorer prognosis than the correctly assessed cases (P < 0.05). Since multivariate logistic regression analysis showed that the significant risk factor related to the inaccurate intraoperative assessment of T stage was tumor size, the error in diagnosis may correlate with a greater degree of tumor spread. Surgeons should decide their therapeutic approach at the time of surgery on the basis of their intraoperative assessment of tumor spread. We recommend extensive surgery followed by adequate chemotherapy when serosal invasion is suspected at surgery.

Adenocarcinoma↗

PubMed1994

In vitro protective effects of nicorandil on hypothermic injury to immature cardiac myocytes: comparison with nitroglycerin.

The purpose of the present study was to evaluate the functional and biochemical effects of nicorandil and nitroglycerin on cardiac myocytes incubated under hypothermic conditions. Nicorandil is a coronary vasodilator with mixed nitrate-potassium channel agonist activity. Cardiac myocytes were isolated from neonatal rat ventricles and cultured for 4 days with MCDB 197 medium. Myocytes (12.5 x 10(5) myocytes/flask) were then incubated at 4 degrees C for 24 hours in media containing various concentrations of nicorandil (NRD) or nitroglycerin (NTG). After hypothermic incubation, CPK and LDH were measured. The myocytes were cultured for an additional 24 hours at 37 degrees C to evaluate the recovery of the myocyte beating rate. In the nicorandil group, 10(-4) M NRD showed a significant beating rate recovery compared to control (44.2% vs. 24.6%, respectively, as a percent of control; i.e., beating rate prior to hypothermic incubation). Nitroglycerin treatment had no effect on either beating rate recovery or release of CPK and LDH from myocytes. However, the release of CPK and LDH was significantly suppressed by 10(-4) M nicorandil compared to the control (10(-4) M NRD: 24.1, 257.2; control: 125.4 mIU/flask, 459.5 mIU/flask, respectively). Thus nicorandil showed an approximate two-fold recovery of myocyte functional activity after hypothermic incubation with only minor biochemical effects, and therefore may be suitable for cardiac preservation.

Animals↗

PubMed1994

In vitro evaluation of phosphate, bicarbonate, and Hepes buffered storage solutions on hypothermic injury to immature myocytes.

In this study we evaluated cardiac myocyte viability and function under hypothermic conditions using three types of buffer solutions: phosphate buffer solution (PBS), Krebs-Henseleit bicarbonate buffer solution (KHB), and Hepes buffered minimum salt solution (MSS). As a control, normal saline solution (NSS) was used. Cardiac myocytes were isolated from neonatal rat ventricles. Myocytes (12.5 x 10(5) myocytes/culture flask) were then incubated at 4 degrees C for 6, 12, 18, and 24 hours in various buffer solutions. After each incubation time, CPK and LDH were measured. The myocytes were then incubated for an additional 24 hours at 37 degrees C to evaluate the recovery of the myocyte beating rate. Group MSS had a significantly better beating rate recovery than group NSS (control) after 18 hours (MSS, 32.7%, NSS, 0.0% of control; i.e., beating rate prior to hypothermic incubation). In contrast, group KHB showed a significantly lower recovery ratio than group NSS at 12 hours (41.0%, 78.8%, respectively), and the lowest recovery was observed in group PBS beginning at 6 hours of hypothermic incubation (27.6%). Group MSS significantly suppressed the release of CPK and LDH compared to group NSS at 24 hours (MSS, 246.7 and 440.2 mIU/flask; NSS, 369.7 and 821.3 mIU/flask, respectively). In contrast, groups PBS and KHB showed significantly increased CPK and LDH levels compared to group NSS after 12 hours (PBS, 388.6 and 721.4 mIU/flask; KHB, 340.5 and 540.5 mIU/flask; NSS, 91.5 and 222.7 mIU/flask, respectively). In conclusion, Hepes buffer has cytoprotective characteristics that may be suitable for long-term hypothermic preservation of immature myocardium compared to phosphate or bicarbonate buffer.

Animals↗

PubMed1994

Spontaneous rupture of the descending aorta through atherosclerotic plaque: report of a case.

Spontaneous rupture of the thoracic descending aorta is rare, and uniformly fatal without surgery. We report herein the case of a man in whom such a rupture was successfully treated with emergency surgery. We believe that the rupture in this patient was most likely associated with perforation through an atherosclerotic plaque of the descending aorta and was induced by sudden hypertension.

Aged↗