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Biomedical subjects

M Washio

Publications and source records attributed to M Washio.

At least 91 records · Page 5Linked to original sources
PubMed1994

Effect of serum concentration on hypothermic preservation of cardiac myocytes isolated from neonatal rat ventricle.

The purpose of the present study was to evaluate the functional and biochemical effects of serum concentrations on hypothermic preservation of cardiac myocytes. Myocytes were isolated from neonatal rat ventricles and cultured for 4 days, and then incubated for 24 hrs at 4 degrees C in media containing 0, 2, 5, 10, and 20% fetal calf serum (FCS). The myocytes were then cultured for an additional 24 hrs at 37 degrees C to evaluate the recovery of myocyte beating rate. The recovery ratio of myocyte beating rate after hypothermic incubation was 25.3 +/- 14.2 percent of control in the serum-free, 33.0% in 2% FCS, 30.7% in 5% FCS, 22.3% in 10% FCS, and 24.3% in 20% FCS groups. Serum-free, 10% and 20% FCS groups had lower recovery ratios compared to the other two groups. The release of CPK and LDH after hypothermic incubation were similar in the serum-free, 2% and 5% FCS groups, however, significant increases were observed for the 10% and 20% FCS groups. It is suggested that fetal calf serum at high concentrations (> 10%) might be injurious to immature myocardium under hypothermic preservation, and that the optimum concentration of FCS is two percent or less.

Animals↗
PubMed1994

Evaluation of immature cardiac myocyte viability after 24 hours of hypothermic preservation.

In this study, we evaluated cardiac myocyte viability and function under hypothermic conditions using three types of storage solutions; saline solution (SS), Euro-Collins solution (ECS) and MCDB 107 medium (MM). Cardiac myocytes were isolated from neonatal rat ventricles by collagenase dispersion and cultured for 4 days with MCDB 107 medium. A total of 12.5 x 10(5) myocytes/culture dish were used and the myocytes were incubated at 4 degrees C for 6, 12, 18 and 24 hrs in the various storage solutions. After each incubation time, CPK and LDH were measured in the storage solutions. The myocytes were then cultured in MCDB 107 medium and incubated for 24 hrs at 37 degrees C to evaluate the recovery of the myocyte beating rate. In group MM (n = 7), the recovery ratio of the myocyte beating rate was 99.2 percent of control (beating rate prior to hypothermic incubation) at 6 hours, 104.6% at 12 hrs and 44.8% at 24 hrs. Groups SS and ECS (n = 7 each) had significantly lower recovery ratios than the MM group (at 6 hrs: 74.3, 34.0; at 12 hrs: 61.0, 32.2; at 24 hrs: 0.0, 0.0 percent of control, respectively). Release of CPK and LDH in the MM group gradually increased and at 24 hrs was 28.6 IU/l and 93.6 IU/l, respectively. However, the SS group had significantly increased CPK and LDH values at 24 hrs (CPK: 66.9, LDH: 164.2). The ECS group showed the greatest increase in both markers (CPK: 317.5, LDH: 421.2). In summary, saline solution showed a beneficial effect on recovery of myocyte viability at 12 hours compared to Euro-Collins solution, however, MCDB 107 medium had the best overall protective effect on cultured myocytes. Accordingly, alternate hypothermic storage solutions, such as cell-culture medium, may have protective characteristics that are suitable for cardiac preservation.

Amino Acids↗
PubMed1994

[Palliative surgery of congenital heart disease in early infancy].

A total of 38 patients aged under 3 months with congenital heart disease (CHD) underwent palliative surgery between April, 1988 and March, 1993. The mean age at operation was 28.0 (range 1 to 87) days. Palliative procedures were: pulmonary artery banding (PAB) in 14 patients (IAA complex: 4, CoA complex: 6, AVSD: 2, TA: 2), Blalock-Taussig shunt (BTS) in 12 (TOF: 2, TGA: 1, AVSD: 1, PA-IVS: 3, PA-VSD: 3, PA-SV: 1, PA-AVSD: 1), Brock operation in 6 (PPS: 2, PA-IVS: 3, PA-SV: 1), Blalock-Hanlon operation (BH) with PAB in 2 (MA-SV: 2) and Norwood operation (NRD) in 4 (HLHS: 4). PAB of IAA or CoA complex was performed just after the repair of IAA or CoA. Overall operative mortality was 23% (PAB: 14.3, BTS: 8.3, Brock: 33.3, NRD: 100%). One week after PAB, pulmonary artery pressure (PAP) decreased significantly compared to the intraoperative PAP value after PAB (43.1 +/- 16.2, 32.3 +/- 9.0 mmHg, p < 0.05, respectively). Pulmonary artery index (PAI), which is an index of pulmonary artery growth, after BTS increased significantly compared to the preoperative value (mean follow-up interval: 22.1 months) (379.5 +/- 101.4, 159.3 +/- 51.2, p < 0.001, respectively). During Brock operation, balloon catheter was used in order to dilate pulmonary valve. One year after Brock operation, mean pressure gradient through the pulmonary valve 22.6 mmHg. Two-staged corrections of CHD will be performed both safely and successfully by effective palliations at the first stages in early infancy.

Cardiac Surgical Procedures↗
PubMed1994

[Tetralogy of Fallot with absent pulmonary valve: a successful case by total corrective surgery in 25 days old infant].

A 25 days old neonate of tetralogy of Fallot with absent pulmonary valve underwent total corrective surgery which consisted of VSD patch closure, resection of anterior wall of both pulmonary arteries and right ventricular outflow tract reconstruction using a monocuspid equine pericardial patch. Postoperatively, the right pulmonary artery diameter decreased from 17.8 mm (307%N) to 7.5 mm (129%N) and the left pulmonary artery diameter from 16.9 mm (338%N) to 8.3 mm (166%N). The patient was weaned from the ventilator 2 days after operation, whose post-operative course was uneventful. Total corrective surgery may provide a great success to symptomatic patients during the neonatal period.

Cardiac Surgical Procedures↗
PubMed1994

[Reoperations for complications after mechanical valve replacement].

Among 310 patients with mechanical valve replacement, 24 patients required reoperations for three types of complications; 12 disc immobilizations on 10 patients, 9 prosthetic valve endocarditis (PVE) on 8 patients and 8 perivalvular leakage or aortic pseudoaneurysm on 7 patients. Long-term survival was 71 percent for PVE and leakage, and 20 percent for emergency surgery of disc immobilization with mean follow up of 67 months. We suggest a few compromised patients with healed fungal endocarditis might show various types of prosthetic valve complications such as tissue ingrowth, late perivalvular leakage or pseudoaneurysmal formation.

Adolescent↗
PubMed1994

Clinicopathological study of poststreptococcal glomerulonephritis in the elderly.

In order to characterize the clinical features in elderly patients with poststreptococcal glomerulonephritis (PSGN), 31 patients, who were both histologically and immunologically proven to be PSGN, were divided up into 3 groups according to age; elderly patients being 55 years or older (n = 7), middle-aged patients being 40 to 54 years old (n = 7) and younger patients being 20 to 39 years old (n = 17). Renal functional impairment as indicated by serum creatinine levels of over 2.0 mg/dl, developed in 4 of the elderly patients and later completely improved at the end of the follow-up period (178.9 +/- 150.7 days). On the other hand, none of the middle-aged and younger patients revealed any renal function impairment. Hypertension was observed more frequently in elderly patients than in younger patients, and was 86% and 6% at the time of admission, respectively. In addition, 43% of elderly patients remained hypertensive at the time of discharge. There was no difference in total protein, ASO, CH50, the degree of proteinuria or proliferative and exudative features in renal histology among the three groups. None of the elderly patients with PSGN died or developed persistent renal failure. In conclusion, elderly patients with PSGN had a high incidence of renal functional impairment and hypertension compared to the younger patients on admission, however, their short-term prognosis seems to be favorable.

Adult↗
PubMed1994

[Cytoprotective effects of nicorandil on immature myocytes under hypothermic conditions].

We evaluated the functional and biochemical effects of nicorandil on cardiac myocytes incubated under hypothermic conditions. Cardiac myocytes were isolated from neonatal rat ventricles and cultured for 4 days. Myocytes (12.5 x 10(5) myocytes/flask) were then incubated at 4 degrees C for 24 hrs in media with nicorandil as follows: O M nicorandil (group C: control), 10(-5)M (group N 1), 5 x 10(-5)M (group N 2), 10(-4)M (group N 3). After hypothermic incubation, CPK and LDH were measured. The myocytes were then cultured for 24 hrs at 37 degrees C to evaluate the recovery of myocyte beating rate. For the beating rate, group N 3 showed a significantly increased recovery compared to the control (N 3: 44.2, p < 0.02, C: 24.6 percent of control; ie, beating rate prior to hypothermic incubation). The release of CPK and LDH was significantly suppressed in group N 3 compared to the control (N 3: 24.1, p < 0.005, 247.2, p < 0.01; C: 125.4 mIU/flask, 459.5 mIU/flask, respectively). Thus, nicorandil has cytoprotective effects on immature myocytes under hypothermic conditions.

Animals↗
PubMed1994

[A case of nontraumatic rupture of ascending aorta].

A 34-year-old man became shock caused by nontraumatic ascending aortic rupture. He was urgently operated. The aortic annulus was mildly ectatic and right coronary cusp was aneurysmal but not perforated. There was a small laceration in the anterior aortic wall without dissection. Cabrol operation was performed.

Adult↗
PubMed1994

[Localized cardiac tamponade after aortic valve replacement: a case report].

We report a case of localized cardiac tamponade after aortic valve replacement. A 56-year-old man had an aortic valve replacement for his aortic valve steno-insufficiency. At 3-postoperative day, severe hypotension occurred, causing acute renal failure. There were no cardiomegaly, high central venous pressure, nor echo-free space. A mass shadow, appearing on chest X-ray at 37-postoperative day, was diagnosed as a localized tamponade by means of a computed tomography and a radioangiography at 38 postoperative day. After the spontaneous drainage of old bloody effusion from the partially opened wound in mid-line, his cardiac and renal failure improved rapidly. When the hematoma is localized, computed tomography is most diagnostic while conventional echo-cardiography often fails to show echo-free spaces.

Aortic Valve↗
PubMed1994

[A rare case of total anomalous pulmonary venous connection to the right atrium confounding with cor triatrium].

Three-days-old newborn baby underwent ligation of the ductus arteriosus under the diagnosis of TAPVC and PDA with high flow heart failure. Her UCG showed the direct connection of common pulmonary venous chamber (CPVC) to the upper and medial portion of right atrium. CPVC positioned just above the left atrium but does not communicated with the left atrium. These findings characterized this anomaly as II A cor triatriatum classified by Lucus-Schumidt. At 5-month-old, corrective operation was performed. Both right and left venous chambers joined just before the connection to right atrium and drained to right atrium at the upper portion of atrial septum. CPVC and left atrium had independent wall. Accordingly, operative diagnosis was made as TAPVC (IIb). Intraatrial routing was performed using porcine pericardial patch. At 6 months after operation, patient is doing well without the sign of venous obstruction. This type of TAPVC is rare and may confound with cor triatriatum. Our case may suggest the pathological mechanism of cor triatriatum and that at least some of cor triatriatum may be identical with TAPVC.

Cardiac Surgical Procedures↗
PubMed1994

Cardiac myocyte functional and biochemical changes after hypothermic preservation in vitro. Protective effects of storage solutions.

In this study, we evaluated cardiac myocyte viability and function under hypothermic conditions with four types of storage solutions, saline solution, Euro-Collins solution, University of Wisconsin solution, and MCDB 107 medium. Cardiac myocytes were isolated from neonatal rat ventricles by collagenase dispersion and cultured for 4 days with MCDB 107 medium. A total of 12.5 x 10(5) myocytes per culture dish was used and the myocytes were incubated at 4 degrees C for 6, 12, 18, and 24 hours in the various storage solutions. After each incubation time, creatine kinase and lactate dehydrogenase were measured in the storage solutions. The myocytes were then incubated for 24 hours at 37 degrees C to evaluate the recovery of the myocyte beating rate. In the MCDB 107 group (n = 7), the recovery ratio of myocyte beating rate was complete by 12 hours, then decreased to 44.8% of control (beating rate before hypothermic incubation) at 24 hours. The saline, Euro-Collins, and University of Wisconsin groups (n = 7 each) had significantly lower recovery ratios than the MCDB 107 group (at 12 hours: 61.0%, 32.2%, and 48.9%; at 18 hours: 0.0%, 5.5%, and 15.1% of control, respectively). Release of creatine kinase and lactate dehydrogenase in the MCDB 107 group gradually increased and at 24 hours was 143.2 mIU/flask and 486.2 mIU/flask, respectively. However, the saline and University of Wisconsin groups had significantly increased creatine kinase and lactate dehydrogenase values at 24 hours (creatine kinase: 334.6 and 319.6 mIU/flask; lactate dehydrogenase: 821.6 and 654.4 mIU/flask, respectively). The Euro-Collins group showed the greatest increase in both markers (creatine kinase: 1587.5, lactate dehydrogenase: 2106.9 mIU/flask). In summary, saline and University of Wisconsin solutions showed a beneficial effect on recovery of myocyte viability at 12 hours compared with Euro-Collins solution, however MCDB 107 medium had the best overall protective effect on cultured myocytes. Accordingly, alternate hypothermic storage solutions, such as cell-culture medium, may have protective characteristics that are suitable for cardiac preservation.

Adenosine↗
PubMed1993

Protection of cardiac myocytes from hypothermic injury by cardiac fibroblasts isolated from neonatal rat ventricle.

In this study, we evaluated the functional and biochemical effects of cardiac fibroblasts (CFs) on cardiac myocytes (CMs) incubated under hypothermic conditions. CMs and CFs were isolated from neonatal rat ventricles and cultures of myocytes only or myocytes in coculture with CFs were established. A CM and CF concentration of 2.5 x 10(5) cells/ml was chosen and the optimum proportion of CF was determined to be 33% (ml CM:ml CF) as follows: 6:0 (group C-a), 4:0 (group C-b), 4:2 (group M-F). On the fourth day of culture, cells were incubated at 4 degrees C for 6, 12, 18, 24, 36 and 48 hr. After each incubation, creatine phosphokinase ((PK) and lactate dehydrogenase (LDH) were measured in the medium, and then the cells were cultured for an additional 24 hr at 37 degrees C to evaluate the recovery of the CM contracting rate. In groups C-a and C-b (n = 6 each), the recovery ratio of CM contracting rate decreased at 18 hr (C-a, 59.0; C-b, 55.6% of control; i.e., contracting rate prior to hypothermic incubation), reaching null levels at 48 hr. However, group M-F (n = 6) showed a significantly increased recovery at 18 hr (95.7%, P < 0.05; at 48 hrs, 27.6%). Release of CPK and LDH in groups C-a and C-b increased gradually by 24 hr and showed a marked increase at 48 hr (C-a, 114.3 x 10(-2), 194.2 x 10(-2); C-b, 81.6 x 10(-2), 118.6 x 10(-2) IU/flask, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Clinico-pathological studies on a transitional type between extrahepatic biliary atresia and paucity of the interlobular bile ducts.

Among the neonatal and infantile cases of obstructive jaundice seen at Niigata and Yamagata University Hospitals between 1976 and 1990, extrahepatic bile ducts were visualized in 19 cases by either preoperative endoscopic retrograde cholangiopancreaticography (ERCP) or intraoperative cholangiography. Neonatal hepatitis was diagnosed in 3 of these cases by clear images of the bile duct system extending from the common bile duct to the intrahepatic bile duct. In 7 cases, the common bile duct was able to be seen, while the common hepatic duct was only slightly visualized. Four of these 7 cases were consistent with paucity of the interlobular bile ducts (PILBD) based on hepatic histology, while the remaining 3 showed fibrosis, bile ductular proliferation, and many bile plugs in the bile ductuli of the portal areas, concurrent with histological changes in extrahepatic biliary atresia (EHBA), not PILBD. In 9 cases, only the common bile duct was visualized while the common hepatic duct was not seen, 7 of these 9 cases being consistent with type III-a1 EHBA. In 2 cases, neither fibrosis nor proliferation of the bile ductuli was observed in the portal areas, and portal areas without any bile ductuli were also seen, in accordance with findings for PILBD. Three cases which showed similar hepatic histological findings to EHBA despite the presence of patent extrahepatic bile ducts, and 2 cases which had obstructed extrahepatic bile ducts and hepatic histological findings similar to PILBD, were thought to be of a transitional type between EHBA and PILBD.(ABSTRACT TRUNCATED AT 250 WORDS)

Bile Duct Diseases↗
PubMed1993

Prevention of postischemic reperfusion injury: the improvement of myocardial tissue blood flow after ischemia by terminal nicorandil-Mg cardioplegia.

We evaluated the preventive effect of postischemic reperfusion injury by Nicorandil-Mg cardioplegia given just prior to reperfusion as "terminal cardioplegia." Twenty seven dogs were placed on cardiopulmonary bypass and the aorta was cross-clamped for 90 min under hypothermic (17-19 degrees C) cardioplegic arrest. The canine hearts were divided into three groups: in group A (n = 10) the hearts reperfused without any treatment; in group B (n = 9) the hearts received coronary perfusion with Nicorandil-Mg solution (Nic, 8 mg/l; Mg, 20 mEq/l; glucose, 50 g/l) for 2 min just prior to reperfusion; and in group C (n = 8) the hearts received coronary perfusion with Nicorandil-Mg free solution (glucose, 50 g/l). During and after ischemia, the myocardial tissue PCO2 (t-PCO2) was continuously monitored by an ion-sensitive field effective transistor (ISFET) sensor. In addition, the myocardial tissue blood flow (TBF), oxygen consumption, and lactate flux were then calculated at 5, 10, 20, and 40 min of reperfusion. In the initial reperfusion period, Group B showed an improved TBF compared to group A and C (at 5 min, group B was 42.7 +/- 11.9; group A was 29.4 +/- 11.2, P < 0.025; and group C was 33.9 +/- 9.2% of the preischemic control level, P < 0.05). T-PCO2 in group B was significantly decreased at 5 min of reperfusion (group B, 127.5 +/- 22.5-->42.5 +/- 9.7; group A, 117.5 +/- 23.0-->85.2 +/- 17.4, P < 0.001; group C, 122.3 mmHg-->68.2 +/- 18.7 mmHg, P < 0.01), and group B had a better metabolic recovery.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

A cardiac myocyte culture system as an in vitro experimental model for the evaluation of hypothermic preservation.

In cardiac transplantation, the donor heart is exposed to severe hypothermic and ischemic conditions. The purpose of the present study was to evaluate the functional and biochemical effects on cardiac myocytes cultured under hypothermic conditions. Cardiac myocytes were isolated from neonatal rat ventricles and cultured for 4 days, then incubated (1.5 x 10(6) myocytes/culture flask) for 24 h in media at 4, 10, 15, 20, and 37 degrees C. In addition, myocytes were incubated at 4 degrees C for 6, 12, 18, 24, 36, and 48 h. After each incubation, creatine phosphokinase (CPK) and lactate dehydrogenase (LDH) were measured and the myocytes then cultured for an additional 24 h at 37 degrees C to evaluate the recovery of the myocyte beating rate. The recovery ratio of the myocyte beating rate following 24 h of varying temperature incubations was complete for the 10, 15, 20, and 37 degrees C groups, although it was markedly decreased in the 4 degrees C group, at 25.1% of the control; taken as the beating rate prior to hypothermic incubation. The release of CPK and LDH in the 4 degrees C group showed a three-fold increase compared to the other four groups, with a CPK of 147.2 mIU/flask and a LDH of 487.5 mIU/flask. The recovery of the beating rate for varying time incubations at 4 degrees C was complete for the 6- and 12-h groups, but decreased significantly in the other four groups, being 59.0% at 18 h, 28.2% at 24 h, 16.3% at 36 h, and 0% at 48 h.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

In vitro evaluation of diltiazem on hypothermic injury to immature myocytes.

The purpose of the present study was to evaluate the functional and biochemical effects of diltiazem (DTZ) on cardiac myocytes incubated under hypothermic conditions. Cardiac myocytes were isolated from neonatal rat ventricles and cultured for 4 days with MCDB 107 medium. Then, myocytes (12.5 x 10(5) myocytes/flask) were incubated at 4 degrees C for 24 hours in media with or without DTZ at concentrations of 0 M (group C), 10(-7) M (Group D1), 10(-6) M (group D2), 10(-5) M (group D3), or 10(-4) M (group D4). After 24 hours at 4 degrees C, CPK and LDH were measured. The myocytes were then cultured for 24 hours at 37 degrees C to evaluate the recovery of the myocyte beating rate. In group C (n = 7), the recovery ratio of the myocyte beating rate was 29.9% of control (beating rate prior to hypothermic incubation). Groups D1 and D2 (n = 7 each) had approximately the same recovery ratios as group C (24.0% and 24.7%, respectively); however, groups D3 and D4 (n = 7 each) showed no beating rate recovery. Release of CPK and LDH in group C was 112.3 mIU/flask and 457.4 mIU/flask, respectively. Groups D1 and D2 showed no significant differences in both enzymes compared to group C. However, the levels of CPK were significantly higher in group D4 (203.3, p < 0.05), and LDH levels were significantly higher in groups D3 and D4 (669.3, p < 0.05; 883.4, p < 0.02). In conclusion, DTZ showed no protective effects on hypothermic injury to immature cardiac myocytes; moreover, it accelerated cellular injury at the concentrations of 10(-5) and 10(-4) M both functionally and biochemically. Therefore, diltiazem may not be suitable for cardiac preservation during the neonatal period.

Animals↗
PubMed1993

Pulsatile low-flow perfusion for enhanced cerebral protection.

We examined the oxygen tension, carbon dioxide tension, and pH in canine brains under profound hypothermia to evaluate the effects of perfusion (circulatory arrest for 1 hour; 25 and 50 mL.kg-1 x min-1 for 2 hours) with and without pulsatile assistance. The effects of pulsatile flow on cerebral blood flow and metabolism were also evaluated in dogs supported by low-flow perfusion (25 mL.kg-1 x min-1) for 2 hours. Profound hypoxia occurred in the brain after 20 to 60 minutes of circulatory arrest. Brain tissue acidosis with hypercapnia was moderated by perfusion at a rate of flow of 50 mL.kg-1 x min-1. Pulsatile low-flow perfusion (25 mL.kg-1 x min-1) moderated cerebral hypercapnia and made the cerebral metabolism aerobic without affecting the total cerebral blood flow and consumption of oxygen.

Acid-Base Equilibrium↗