Biomedical subjects

K Ishino

Publications and source records attributed to K Ishino.

At least 19 recordsLinked to original sources

PubMed2003

[Lateral tunnel versus extracardiac cavopulmonary connections].

To examine the mid term outcome of the lateral tunnel Fontan and the result is to be compared to extracardiac Fontan operation. Between March 1991 and May 2002, 72 lateral tunnel (LT) and 28 extracardiac conduit (EC) total cavopulmonary connection (TCPC) were performed. Right atrium was incised parallel to the sulcus terminalis and LT was created by using autologous right atrial wall. Lateral tunnel size was determined 1-2 mm larger than normal half pulmonary artery (PA) size according to the body weight. There were 1 early and 1 late death, both initial LT group. Supraventricular tachycardia was found in 1 patient with EC group and 4 in LT group (all heterotaxy syndrome). There were no differences in mortality and mobidity between LT and EC TCPC. Lateral tunnel TCPC is useful especially to small infants and children.

Adolescent↗

PubMed2001

[Right ventricular outflow tract reconstruction using monocusp valved outflow patch for pulmonary atresia with ventricular septal defect: influence of the presence of major aorto-pulmonary collateral arteries].

We have preferably utilized monocusp valved outflow patch (MVOP) for right ventricular outflow tract (RVOT) reconstruction in pulmonary atresia with ventricular septal defect (PA + VSD). The purpose of this study was to evaluate the influence of the presence of major aorto-pulmonary collateral arteries (MAPCAs) on probability of MVOP reconstruction and development of RVOT restenosis in midterm. 49 patients underwent complete repair (either MVOP reconstruction or Rastelli procedure) of PA + VSD in our service. These patients were divided into 2 groups: group 1; 21 patients with MAPCAs, group 2; 28 patients without MAPCAs. There was one operative death (group 1). The probably of MVOP reconstruction was similar between group 1 and group 2 (71 vs 79%, p = 0.57, chi 2 test). Follow-up was completed for 48 survivors with the period ranged 3-108 months (mean 47 months). In group 1, one patient died suddenly at home 10 months after surgery. For 47 long-term patients, the ratio of freedom from RVOT restenosis was 72% (95% CI: 52-92%, Kaplan-Meier method) at 5 year. There was no difference between 2 groups (group 1; 73%, 95% CI: 45-100%, group 2; 74%, 95% CI: 48-99%, respectively, p = 0.85 by Log-Rank test). The presence of MAPCAs in PA + VSD was not a risk factor for either the probably of MVOP reconstruction or development of RVOT restenosis in midterm.

Adolescent↗

PubMed2001

[Surgical treatment of transposition of the great arteries: the arterial switch operation].

Transposition of the great arteries (TGA) is one of the most common congenital cardiac anomalies resulting in cyanosis. Various atrial-level physiological procedures were developed in the late 1950s and early 1960s, including the Senning and Mustard procedure. In 1975, Jatene et al. reported the first successful arterial switch procedure in a patient with d-TGA and ventricular septal defect. In 1977, Yacoub et al. introduced a two-stage repair comprising initial pulmonary artery banding to retain the left ventricle, supplemented by a systemic-pulmonary artery shunt, thereby potentially expanding the arterial switch procedure to a much wider population of patients. In 1983, the concept of the primary neonatal arterial switch procedure was introduced by Castaneda et al. Since then, the primary artery switch procedure in neonates and early infants has become the standard for the treatment of TGA. This is due to the fact that the only the arterial switch procedure allows complete anatomical repair. In Japan, 102 neonates with simple TGA underwent the arterial switch procedure, with hospital death occurring in 21 (20.6% mortality rate) according to the 1998 annual report. In Okayama University Hospital, 48 neonates, underwent the arterial switch procedure, with 1 hospital death (2.1% mortality rate) and no late deaths since 1991.

Humans↗

PubMed2001

[Isolated cerebral and myocardial perfusion during aortic arch repair in neonates].

OBJECTIVES: To prevent possible neurologic injury after hypothermic circulatory arrest, aortic arch obstruction with cardiac defects is repaired in one stage using isolated cerebral and myocardial perfusion (ICMP). This study investigated serum S-100 protein(S-100) levels in neonates undergoing ICMP. METHODS: Between February 2000 and January 2001, 19 neonate patients underwent repair of critical congenital heart defects. Seven of these patients with aortic coarctation(n = 3) or interrupted aortic arch (n = 4) with ventricular septal defect(ICMP group) underwent primary total repair. An arterial cannula was inserted either into the ascending aorta or into a polytetrafluoroethylene graft which was anastomosed to the innominate artery. During arch repair, a cross-clamp was placed between the innominate and left carotid arteries, and an end-to-end arch anastomosis was performed with cerebral perfusion and heart beating. During ICMP the flow was reduced to maintain a radial artery pressure of 30-45 mmHg. The remaining 12 patients underwent complete transposition of great arteries(n = 9) or total anomalous pulmonary venous connection(n = 3) using a cardiopulmonary bypass(CPB) with flow of 150-180 ml/kg/min(control group). Sequential blood samples for S-100 determinations were taken after induction of anesthesia, 30 min after aortic declamping(post-ACC), 30 min after CPB, and 24 hr after CPB. RESULTS: There were no early and late deaths. Neurologic symptoms were not observed in any patients. Mean ICMP time in ICMP group was 17 +/- 4 min. In all patients, S-100 showed the highest value post-ACC and then declined with time. There were no differences in S-100 between the groups at any other time point. CONCLUSIONS: Selective cerebral perfusion through the innominate artery may be able to maintain brain circulation.

Aorta, Thoracic↗

PubMed2000

PKCeta associates with cyclin E/cdk2/p21 complex, phosphorylates p21 and inhibits cdk2 kinase in keratinocytes.

PKC is activated on the cell membrane by phospholipids, thereby transducing signals to intracellular pathways. We provide here another function of PKC, namely, regulating cell cycle by interaction with the cyclin E/cdk2/p21 complex. Among the 10 isoforms of PKC, PKCeta is predominantly expressed in squamous cell epithelia and induces terminal differentiation of keratinocytes. PKCeta that is endogenously expressed or overexpressed was found to associate with the cyclin E/cdk2/p21 complex in keratinocytes of mice and humans. Requirement of a possible adaptor protein to the binding was suggested by the reconstitution of PKCeta and the cyclin E/cdk2/p21 complex which were prepared from human keratinocytes or Sf9 insect cells. Colocalization of PKCeta with cdk2 and cyclin E was observed in the cytoplasm, particularly in the perinuclear region. p21 was phosphorylated in the complex in a PKC-activator dependent manner. Association of PKCeta with cdk2 resulted in marked inhibition of cdk2-kinase activity when measured by phosphorylation of Rb. Dominant negative PKCeta associated with the cyclin E/cdk2/p21 complex, but caused a little inhibition of cdk2 kinase activity. Among the known regulatory mechanisms of cdk2 activity, dephosphorylation of Thr160 was demonstrated. Oncogene (2000) 19, 6334 - 6341.

Animals↗

PubMed2000

Specific decrease in the level of Hic-5, a focal adhesion protein, during immortalization of mouse embryonic fibroblasts, and its association with focal adhesion kinase.

Hic-5 is a paxillin homologue with four LIM domains in its C-terminal region, localized mainly in focal adhesions in normal fibroblasts. Hic-5 is also known to associate with focal adhesion kinase (FAK) or the related CAKbeta, and with vinculin. In the present study, we examined changes in Hic-5 and paxillin protein levels in primary mouse embryo fibroblasts (MEF) during mortal and immortal stages. The Hic-5 level was markedly decreased when cells became immortalized, whereas that of paxillin was increased. The vinculin level was not changed significantly. Hic-5 was mainly localized in focal adhesion plaques of mortal MEF but was localized in the nuclear periphery in the immortalized MEF; the number of focal adhesion plaques was decreased in these cells. Mouse Hic-5 contains three LD domains in its N-terminal half, and the first LD domain (LD1) appears to be involved in interaction with FAK. However, this interaction was not essential for recruitment of Hic-5 to focal adhesions, since its subcellular localization was similar in FAK(-/-) cells. Forced expression of Hic-5 decreased colony forming ability of MEF from FAK(+/+) mice, but not of FAK(-/-) cells. These observations suggested the involvement of Hic-5 in determination of cellular proliferative capacity in collaboration with other cytoskeletal components.

Amino Acid Sequence↗

PubMed2000

Staged biventricular repair of pulmonary atresia or stenosis with intact ventricular septum.

BACKGROUND: Since 1991 we have performed a multistage palliative approach to biventricular repair of pulmonary atresia or critical pulmonary stenosis with intact ventricular septum in infants with a detectable right ventricular infundibulum. METHODS: A total of 25 patients (19 pulmonary atresia and 6 critical pulmonary stenosis) underwent initial palliation consisting of a transarterial pulmonary valvotomy and a polytetrafluoroethylene shunt between the left subclavian artery and pulmonary trunk. Among the 23 survivors, 15 underwent balloon valvotomy. Six of these patients later required additional palliative surgery that consisted of repeat pulmonary valvotomy, adjustment of an atrial communication, and resection of the hypertrophied muscles in the right ventricle. RESULTS: Of the 25 patients, 23 (92%) survived. In all, 20 patients underwent definitive operations: 18 (90%) biventricular repair (12 pulmonary atresia, and 6 critical pulmonary stenosis), one bidirectional Glenn, and one Fontan procedure. The actuarial probability of achieving a biventricular repair at 36 months of age was 69%. In 18 patients right ventricular end-diastolic volume significantly increased but tricuspid valve diameter did not change. CONCLUSIONS: The multistage palliation procedure to promote right ventricular growth makes a definitive biventricular repair of pulmonary atresia or critical pulmonary stenosis with intact ventricular septum possible in the majority of infants with a patent infundibulum.

Cardiac Surgical Procedures↗

PubMed2000

Single-stage repair of aortic coarctation with ventricular septal defect using isolated cerebral and myocardial perfusion.

OBJECTIVE: To avoid hypothermic circulatory arrest, we have repaired aortic coarctation with ventricular septal defect (VSD) in a one-stage procedure using an isolated cerebral and myocardial perfusion technique, and retrospectively compared this novel approach to the conventional two-stage approach. METHODS: Between October 1991 and February 1999, 24 infants, aged 4-137 days (median, 27 days) and weighing 1.7-4.3 kg (median, 3.0 kg), underwent the repair of aortic coarctation with VSD either in one (group I, n=11) or two stages (group II, n=13). In Group I, an arterial cannula for cardiopulmonary bypass was inserted into the ascending aorta in six patients with coarctation only, or into a polytetrafluoroethylene (PTFE) graft which was anastomosed to the innominate artery in the remaining five who had hypoplastic arches. A cross-clamp was placed between the innominate and left carotid arteries. The bypass flow was reduced to 30-50% of full flow at 28 degrees C, thereby maintaining a radial artery pressure of 30-45 mmHg. At this point, the aortic coarctation was repaired by an end-to-end arch anastomosis, while maintaining brain perfusion and with the heart still beating. In five patients with hypoplastic aortic arches, the innominate artery proximal to the graft was then secured down and the arch anastomosis was extended to the distal ascending aorta, while providing isolated cerebral perfusion and cardioplegic arrest. After arch reconstruction was performed, the clamp was moved onto the ascending aorta, and the VSD was closed with systemic perfusion. In contrast, for group II patients, coarctation repairs were performed through a posterolateral approach, and existing VSDs were closed as secondary procedures. RESULTS: The mean isolated cerebral and myocardial perfusion time for group I was 13 min (range, 7-20 min). The myocardial ischemic time did not differ between groups I and II (43+/-4 vs. 42+/-5 min, not significant). There were no hospital mortalities or neurological complications in either group, but one late death in each group. CONCLUSION: Single-stage repair of aortic coarctation with VSD does not increase myocardial ischemic time compared to the traditional two-stage approach. The isolated cerebral and myocardial perfusion technique may offer substantial brain and myocardial protection during aortic arch reconstruction.

Aortic Coarctation↗

PubMed1999

Myocardial adenine nucleotides, glycogen, and Na, K-ATPase in patients with idiopathic dilated cardiomyopathy requiring mechanical circulatory support.

Acute decompensation leading to progressive pump failure is a main cause of death in patients with congestive heart failure. To find possible metabolic defects associated with the onset of this fatal occurrence, we measured myocardial adenine nucleotides, glycogen, and Na,K-ATPase in patients with end-stage idiopathic dilated cardiomyopathy. The biopsy specimens were obtained from the right ventricle of beating hearts during implantation of a biventricular assistance device in 23 patients (group I) suffering from irreversible cardiogenic shock and during heart transplantation in 20 patients (group II) in compensated heart failure. Left ventricular ejection fraction (LVEF) was determined preoperatively by echocardiography. Left ventricular function in group I was more severely impaired than in group II (LVEF 16.8%+/-4.6% vs 22.1%+/-5.1 %; p <0.01). Myocardial adenosine triphosphate (ATP) in group I was significantly reduced in comparison with group II (119.4+/-10.2 vs 27.7+/-7.4 nmol/mg noncollagen protein; p <0.01). There was no difference in glycogen levels. Na,K-ATPase concentration in group I (n = 8) was lower than that of group II (n = 20) (425+/-80 vs 498+/-75 pmol/g wet weight; p <0.05). Linear regression analyses showed a significant correlation between adenosine triphosphate (ATP) and LVEF (r = 0.41, p <0.01) and between Na,K-ATPase and LVEF (r = 0.55, p <0.01). These results indicate that loss of myocardial ATP and Na,K-ATPase could partially contribute to the development of spontaneous deterioration of the chronically overloaded heart.

Adenine Nucleotides↗

PubMed1999

The modified Norwood procedure for hypoplastic left heart syndrome: early to intermediate results of 120 patients with particular reference to aortic arch repair.

BACKGROUND: Classic first-stage Norwood repair of hypoplastic left heart syndrome uses a homograft patch enlargement to obtain an unobstructed aorta and coronary arteries. Because of possible disadvantages of the homograft, such as lack of growth, degeneration and calcification, and availability, we have tried to repair the aorta without patch supplementation. METHODS: Between February 1993 and September 1997, 120 patients, aged birth to 47 days (median 4 days) and weighing 1.7 to 4.4 kg (median 3.1 kg), underwent first-stage palliation for hypoplastic left heart syndrome. The diameter of the ascending aorta ranged from 1.5 to 8.0 mm (median 3.0 mm). Eight patients had an aberrant right subclavian artery arising from the descending thoracic aorta. In 95 patients (group I), all duct tissue was excised and the descending aorta was anastomosed to the aortic arch, which had been opened back into the ascending aorta. Then to this confluence was anastomosed the proximal main pulmonary artery. In the remaining 25 patients (group II), continuity of the aortic arch was maintained and the repair was performed with a Damus-Kaye-Stansel anastomosis. The size of the systemic-to-pulmonary shunt was 3 mm in 48 patients, 3.5 mm in 70, and 4.0 mm in 2. RESULTS: Circulatory arrest time ranged from 19 to 105 minutes (median 54 minutes). A homograft patch was necessary for the arch reconstruction in 18 patients (15%); 9 group I patients (10%) and 9 group II (36%) (P =.001). There were 82 hospital survivors (68%); 69 group I patients (73%) and 13 group II (52%) (P =.04), 71 patients without a patch (70%) and 11 with a patch (61%) (P >.2). By multiple logistic regression, the aberrant right subclavian artery was a significant risk factor for hospital death (P =.008). There were 6 late deaths. Sixteen of 71 patients (23%) who underwent second-stage palliation had a neoaortic arch obstruction develop, with a peak gradient greater than 10 mm Hg; 14 group I patients (23%) and 2 group II (22%) ( P >.2), 15 without a patch (23%) and 1 with a patch (17%) (P >.2). Overall survivals were 57% at 1 year and 55% at 2 years. CONCLUSION: The modified Norwood procedure for first-stage palliation of hypoplastic left heart syndrome is possible in the majority of patients without the use of exogenous materials and does not result in an increased incidence of neoaortic arch obstruction. Repair of the aorta without patch supplementation may improve the potential for long-term growth of the new aorta.

Anastomosis, Surgical↗

PubMed1999

Preoperative extracorporeal membrane oxygenation in newborns with total anomalous pulmonary venous connection.

This report describes three neonates who were supported with extracorporeal membrane oxygenation before surgical correction of total anomalous pulmonary venous connection. Extracorporeal membrane oxygenation was initially used to treat preoperative end-organ failure and suspected persistent pulmonary hypertension. All patients underwent surgical correction of total anomalous pulmonary venous connection after 8, 4 and 4 days of preoperative support, respectively. Two of these patients required extracorporeal membrane oxygenation after surgery; one died from bleeding while the other was weaned from extracorporeal membrane oxygenation on day 8 and discharged from the hospital. These results show that veno-arterial extracorporeal membrane oxygenation represents a life-saving perioperative means for supporting moribund neonates with total anomalous pulmonary venous connection and is effective in improving preoperative patient's condition.

Cardiac Surgical Procedures↗

PubMed1999

Adenovirus-mediated gene transfer to keratinocytes--a review.

The introduction and expression of a foreign gene provide a powerful tool for investigating functions and regulation of a gene of interest; however, keratinocytes have a major drawback in that foreign genes are hardly transfected by conventional methods and stable transformants are most difficult to establish in normal keratinocytes with a limited short life span. To overcome these problems, we used an adenovirus vector, Ax, developed by Saito et al, which yields desired recombinant viruses at an efficiency about 100-fold that of conventional methods, and by which genes are expressed at a high level under the control of a composite CAG promoter. We established Ax vectors carrying various isoforms of protein kinase C (PKC). Using these vectors, we found that the eta and delta isoforms of PKC, but not the alpha and zeta isoforms, mediate terminal differentiation in normal human keratinocytes. These Ax-vectors are also applicable to organ culture of mouse embryos. Advantages and disadvantages of adenovirus vectors and their use for keratinocyte biology are reviewed.

Adenoviridae↗

PubMed1998

Cannulation-induced coronary artery dissection: successful management with circulatory assist devices and coronary bypass grafting.

A coronary artery dissection is a rare but well-known lethal complication associated with coronary perfusion. We herein report the case of a right coronary dissection that occurred after an aortic valve replacement. Coronary bypass grafting was successful after the establishment of mechanical biventricular support with an intra-aortic balloon pump and a right ventricular assist device.

Aortic Valve↗

PubMed1998

Phorbol ester-induced G1 arrest in BALB/MK-2 mouse keratinocytes is mediated by delta and eta isoforms of protein kinase C.

We investigated the possible negative regulation of the cell cycle by protein kinase C (PKC) isoforms in synchronously grown BALB/MK-2 mouse keratinocytes, in which PKC isoforms were overexpressed by using the adenovirus vector Ax. Cells at the G1/S boundary of the cell cycle were the most sensitive to the inhibitory effect of 12-O-tetradecanoylphorbol-13-acetate (TPA), a PKC agonist, resulting in G1 arrest. TPA-induced inhibition of DNA synthesis was augmented by overexpression of the eta and delta isoforms, but rescued by the dominant-negative and antisense eta isoforms. In contrast, the alpha and zeta isoforms showed no effect on DNA synthesis with or without TPA treatment. Immunoblotting indicated cell cycle-dependent expression of the eta isoform, being highest in cells at the G1/S boundary. The present study provides evidence that the eta and delta isoforms of PKC are involved in negative regulation of cell cycle at the G1/S boundary in mouse keratinocytes.

Adenoviridae↗

PubMed1998

Induction of differentiation in normal human keratinocytes by adenovirus-mediated introduction of the eta and delta isoforms of protein kinase C.

Protein kinase C (PKC) plays a crucial role(s) in regulation of growth and differentiation of cells. In the present study, we examined possible roles of the alpha, delta, eta, and zeta isoforms of PKC in squamous differentiation by overexpressing these genes in normal human keratinocytes. Because of the difficulty of introducing foreign genes into keratinocytes, we used an adenovirus vector system, Ax, which allows expression of these genes at a high level in almost all the cells infected for at least 72 h. Increased kinase activity was demonstrated in the cells overexpressing the alpha, delta, and eta isoforms. Overexpression of the eta isoform inhibited the growth of keratinocytes of humans and mice in a dose (multiplicity of infection [MOI])-dependent manner, leading to G1 arrest. The eta-overexpressing cells became enlarged and flattened, showing squamous cell phenotypes. Expression and activity of transglutaminase 1, a key enzyme of squamous cell differentiation, were induced in the eta-overexpressing cells in dose (MOI)- and time-dependent manners. The inhibition of growth and the induction of transglutaminase 1 activity were found only in the cells that express the eta isoform endogenously, i.e., in human and mouse keratinocytes but not in human and mouse fibroblasts or COS1 cells. A dominant-negative eta isoform counteracted the induction of transglutaminase 1 by differentiation inducers such as a phorbol ester, 1alpha,25-dihydroxyvitamin D3, and a high concentration of Ca2+. Among the isoforms examined, the delta isoform also inhibited the growth of keratinocytes and induced transglutaminase 1, but the alpha and zeta isoforms did not. These findings indicate that the eta and delta isoforms of PKC are involved crucially in squamous cell differentiation.

Adenoviruses, Human↗

PubMed1998

Increase in telomere sequence-binding activity in normal human fibroblasts in senescence or in cells treated with phorbol ester or N-methyl-N'-nitro-N-nitrosoguanidine.

The telomere is a specialized chromatin structure composed of unique repetitive DNA sequences and specific nuclear proteins. Telomere sequence-binding activity was measured by a mobility shift assay using nuclear extract from normal human fibroblasts. The specific binding activity to the telomere sequence increased in cells that were in a senescence state compared to that in cells at early population doublings. Treatment of cells with tumor promoting phorbol ester TPA induced an increase in the telomere sequence binding activity of nuclear extract in young cells, but the increase was marginal in senescent cells. DNA-damaging N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) also increased the telomere sequence binding activity in young cells, but not in senescent cells. As a reference, we measured the binding activity to NFkB sequence. It was activated by TPA or okadaic acid, but was not affected by MNNG or in senescence. The increase in telomere sequence-binding activity seemed to depend on activation of tyrosine phosphorylation, since an inhibitor of Tyr-kinase abolished the increase in telomere-binding activity. The molecular weight of the major binding factor in the normal human fibroblasts was approximately 32 kDa which is different from that of the telomere-associated protein, TRF-1.

Carcinogens↗

PubMed1997

Myocardial recovery through ECMO after repair of total anomalous pulmonary venous connection: the importance of left heart unloading.

A 7-day-old boy who had been placed on extracorporeal membrane oxygenation on his second day of life developed biventricular failure after undergoing surgical repair of a supracardiac variant of total anomalous pulmonary venous connection. Extracorporeal membrane oxygenation was again necessary for postoperative cardiopulmonary support. However, severe left ventricular failure made it imperative to leave the vertical vein open during support in order to decrease pressure on the left ventricle. The patient was successfully weaned from extracorporeal membrane oxygenation on day 8 after surgery and discharged from the hospital on day 23.

Blood Pressure↗

PubMed1997

Circulatory support with paracorporeal pneumatic ventricular assist device (VAD) in infants and children.

OBJECTIVE: The feasibility and efficacy of the pneumatic 'Berlin Heart' ventricular assist device (VAD) were evaluated in 14 pediatric patients with profound cardiogenic shock refractory to conventional therapy. METHODS: There were two patient groups. Eleven patients, aged 2 weeks 15 years and weighing 3.2-52 kg received a left ventricular assist device or a biventricular assist device as a bridge to cardiac transplantation (bridge group). Nine of them had liver, kidney, or lung dysfunction before device implantation. Three patients were supported with a biventricular assist device for myocardial recovery (recovery group): a 6-month-old girl for postcardiotomy shock, a 10-month-old girl for allograft failure after cardiac transplantation, and a 4-year-old boy with acute myocarditis. RESULTS: In the bridge group, eight patients were transplanted after a bridge duration of 6-98 days (mean, 32 days) with five long-term survivors. Organ functions were normalized during bridging in all of the transplant recipients. In the recovery group, the first patient was removed from support after 2 days because of irreversible brain damage. The second patient was weaned from biventricular support after 8 days, but suffered from recurrent allograft failure. The third patient received biventricular support for 21 days followed by extracorporeal membrane oxygenation and was subsequently discharged from the hospital. CONCLUSIONS: The 'Berlin Heart' VAD can keep selected infants and children with life-threatening heart failure for weeks or months.

Adolescent↗