Biomedical subjects

H Tsuboi

Publications and source records attributed to H Tsuboi.

At least 73 records · Page 4Linked to original sources

PubMed1996

[A case of pulmonary sarcoma with a differential diagnosis from preoperative pulmonary thromboembolism].

Primary sarcoma of pulmonary artery is a rare tumor. A 46-year-old man was hospitalized because of dyspnea and hemoptysis. Pulmonary thromboembolism was suspected by chest X-ray, scintigraphy, and CT. But the mass had a to-and-fro movement above the pulmonary valve on pulmonary arterial cineangiography. We strongly suspected that it was primary neoplasm of pulmonary artery. The pulmonary artery was opened under cardiopulmonary bypass. The tumor arised pulmonary trunk and extended peripherally. The tumor was surgically removed as complete as possible, though a proxymal balloon embolectomy was unsuccessful. The histological finding was malignant fibrous histiocytoma of the pulmonary artery.

Cardiopulmonary Bypass↗

PubMed1996

[A case report of open heart surgery in an infant with MNMS caused by femoral arterial cannulation during cardiopulmonary bypass].

We report a case of myonephropathic metabolic syndrome (MNMS) and compartment syndrome caused by femoral arterial cannulation during long-term cardiopulmonary bypass. A boy who had been diagnosed with truncus arteriosus type 1 and who subsequently underwent a Rastelli operation at age 3 months had a second Rastelli operation at age 6 years due to graft stenosis (pressure gradient 82 mmHg between RV and PA). MNMS and compartment syndrome occurred postoperatively due to long-term femoral arterial cannulation during cardiopulmonary bypass. However, acute renal failure was successfully managed with CAPD. The patient recovered from acute renal failure 40 days postoperatively. CAPD is considered useful for postoperative acute renal failure in infants. We conclude that retrograde insertion of the cannula should be changed to anterograde insertion at an earlier time, or else the cannula should be inserted via the prosthetic graft.

Acute Kidney Injury↗

PubMed1996

[Reconstruction of right ventricular outflow tract-pulmonary artery utilizing autologous tissue in extreme tetralogy of Fallot after coil embolization for major aortopulmonary collateral artery: report of a case].

We report a successful surgical treatment for tetralogy of Fallot with pulmonary atresia. A 18-year-old girl was admitted because of increasing exertional dyspnea and cyanosis. She had undergone bilateral classical Blalock-Taussing shunt. Prior to the correction, two major aortopulmonary collateral arteries were embolized using steel coils. Under cardiopulmonary bypass, posterior wall of the pulmonary artery was anastomosed directly to the cranial margin of the ventriculotomy for a floor made of autologous tissue. The roof was reconstructed using a patch with a monocusp. The patient is in a good postoperative condition. A coil embolization is useful and this reconstruction utilizing autologous tissue could prevent a late stenosis of the reconstructed pulmonary artery tract.

Adolescent↗

PubMed1996

[Usefulness of scheduled IABP for CABG].

We examined the usefulness of intra-aortic balloon pumping (IABP) before the coronary arterial bypass grafting (IABP) before the coronary arterial bypass grafting (CABG) in patients with severe ischemic heart disease. Left main trunk (LMT) disease, unstable angina and low ejection fraction (less than 40%) were indications for scheduled IABP. Eleven patients underwent IABP before CABG surgery (the scheduled IABP group), and five patients didn't before CABG surgery (the unscheduled IAPB group). Analysis comprised the duration of IABP and mortality. There were no significant differences between the two groups in age, pre-operational cardiac index, ejection fraction, aorta clamp time or total perfusion time. IABP application times were significantly longer in the unscheduled IABP group than in the scheduled IABP group (p < 0.05). No death occurred in the scheduled group, but three patients in the unscheduled group died (p < 0.05). No complications were observed due to IABP in any patient of either group. We conclude that scheduled IABP is useful for patients with severe ischemic heart disease.

Aged↗

PubMed1996

[A case of report of traumatic aortic regurgitation accompanying cerebral embolism].

Aortic regurgitation due to nonpenetrating trauma of the chest is an extremely rare disease and only 12 cases have been reported in this country. We report a case we treated and present additional of retrospective discussions. The patient was a 59-year-old man who lost consciousness due to a heavy blow to the chest during work. He was diagnosed as having acute aortic regurgitation. A close examination on the 3rd day after the injury revealed cerebral embolism and heart failure could not be controlled by physical treatment. Surgery was performed on the 5th day after the injury. The aorta was incised under cardiopulmonary bypass to examine aortic valves. Commissures between the RCC and the NCC and between the NCC and the LCC had been torn from the aortic wall and injured and thrombus adhesion was observed in a part of the NCC. After repairing the aortic wall, the valve was replaced by SJM valve. Postoperative course is satisfactory.

Aortic Valve↗

PubMed1995

Flow stimulates ICAM-1 expression time and shear stress dependently in cultured human endothelial cells.

Human umbilical vein endothelial cells were subjected to controlled levels of shear stress in a flow-loading apparatus, and changes in the expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) were measured by flow cytometry. Application of shear stress (15 dynes/cm2) increased the cell surface expression of ICAM-1 2.7 times the control level 4 hr after the onset of flow, while it caused no change in VCAM-1 expression. The increase of ICAM-1 expression by shear stress was time- and force-dependent and reversible. Flow loading using perfusates with different viscosity revealed that the increase in ICAM-1 was shear-stress- rather than shear-rate-dependent. Reverse transcriptase/polymerase chain reaction analysis showed upregulation of ICAM-1 mRNA levels by shear stress, whose time course closely paralleled that of the cell surface protein. These results suggest that shear stress generated by blood flow acts as a regulator of cell adhesion molecule expression on vascular endothelial cells.

Base Sequence↗

PubMed1995

Down-regulation of vascular adhesion molecule-1 by fluid shear stress in cultured mouse endothelial cells.

This study was undertaken to determine whether blood flow modulates the adhesive property of vascular endothelial cells to lymphocytes and, if it does, what adhesion molecules are involved. Cultured mouse endothelial cells were exposed to medium flow in a parallel plate chamber, and binding assay using fluorescence-labeled lymphocytes was carried out. The adhesion rate of endothelial cells to lymphocytes, which was high in the static control state, decreased when exposed to shear stress (1.5 dynes/cm2) for 6 h. The treatment of static endothelial cells with a monoclonal antibody of vascular cell adhesion molecule-1 (VCAM-1) depressed the adhesion rate to the same extent as that caused by flow, while monoclonal antibodies of CD44 and intercellular adhesion molecule-1 had no effect on it. Flow cytometric analysis revealed that the application of flow decreased markedly the amount of VCAM-1 expressed on the cell surface. A reverse transcriptase-polymerase chain reaction of mRNA showed that flow depressed VCAM-1 mRNA levels. These results suggest that blood flow can modulate the adhesive property of endothelial cells to lymphocytes via affecting the surface expression of adhesion molecules, e.g., down-regulation of VCAM-1.

Animals↗

PubMed1995

Efficacy of benidipine hydrochloride on myocardial ischemia and reperfusion.

The efficacy of benidipine hydrochloride in preventing myocardial ischemia and reperfusion injury was evaluated in isolated rabbit hearts (n = 28). Isovolumic left ventricular function, coronary flow, creatine phosphokinase (CPK) release, and myocardial water content were measured after ischemia during both normothermia (37 degrees C; Group I) and hypothermia (23 degrees C; Group II). After baseline measurements, hearts were induced to arrest by chilled cardioplegic solution. Each group was divided into two subgroups, depending upon whether benidipine hydrochloride (10(-9) mole/liter) was added in the cardioplegia (A, without benidipine; B, with benidipine). After 30 min of ischemia for Group I and 180 min for Group II (which added another cardioplegia every 30 min), hearts were reperfused. Measurements the same as those at baseline were carried out every 15 or 30 min for up to 60 min. Benidipine-treated hearts started beating in a shorter time than did control hearts (Group I-B, 38.7 +/- 3.7 sec vs Group I-A, 59.9 +/- 5.6; Group II-B, 36.7 +/- 2.0 vs Group II-A, 47.8 +/- 3.3). The percentage of recovery of left ventricular developed pressure after 60 min of reperfusion was significantly better in benidipine groups (P < 0.05). With respect to changes in coronary flow and CPK release after reperfusion, benidipine groups were preserved extremely well. We conclude that the addition of benidipine hydrochloride to cardioplegic solution significantly improves ventricular function after myocardial ischemia and reperfusion.

Animals↗

PubMed1995

Clinical significance of no-reflow phenomenon observed on angiography after successful treatment of acute myocardial infarction with percutaneous transluminal coronary angioplasty.

The clinical significance of the angiographic no-reflow phenomenon was evaluated in 93 patients with acute myocardial infarction treated by percutaneous transluminal coronary angioplasty (PTCA). On the basis of the post-PTCA angiograms, patients were divided into three groups: normal angiogram (group 1, n = 65), slight no-reflow (group 2, n = 13), and severe no-reflow (group 3, n = 15). Regional wall motion in the chronic phase was depressed in groups 2 and 3 compared with group 1. The proportion of the area of the transmural infarction to that of the total infarction determined by scintigraphy was higher in groups 2 and 3 than in group 1. A significantly higher incidence of myocardial rupture and of death resulting from cardiac causes was observed in group 3 compared with group 1. The severity of this phenomenon immediately after an emergency PTCA correlated well with the severity of myocardial damage, with patients having severe no-reflow showing the poorest prognosis.

Adult↗

PubMed1995

[Clinical evaluation of patients with cardiopulmonary bypass by plasma granulocyte elastase].

To evaluate the role of granulocyte elastase (GEL) at cardiopulmonary bypass (CPB), the plasma GEL level was measured in 24 patients who underwent elective cardiac surgery and 47 patients who underwent elective gastroenterological surgery. The cardiac surgical patients were divided into two groups: 5 patients with CPB less than 120 minutes (HL group), and 19 patients with CPB more than 120 minutes (HH group). The patients with gastro-enterological surgery were also divided into two groups: 15 patients with postoperative complications (GC group), and 32 patients without postoperative complications (GU group). All the patients of GU, HL and HH groups were alive. Two patients of GC group died because of multiple organ failure (MOF). The serum levels of GEL in both the HH group and the GC group remained higher than in the GU group at 6 postoperative day (POD). The high serum level of IL-8 gave rise to high serum level of GEL in the HH group, even after cardiac surgery. We assumed that anti-cytokine therapy and aggressive administration of Ulinastatin are useful against postoperative complications and that careful management is need after long CPB.

Cardiac Surgical Procedures↗

PubMed1995

Focused-ion-beam digging of biological specimens.

The focused ion beam (FIB) technique has been applied for digging damageable biological specimens of human hair and the housefly eye. Sharp cross-sections have been formed for these specimens and their cross-sectional structures have been observed in scanning ion microscope (SIM) images. The applicability of FIB has been confirmed for these biological specimens.

Animals↗

PubMed1995

[Clinical analysis of the surgical therapy of DeBakey type I acute aortic dissection].

We investigated relation of operative mortality with factors such as during from onset to operation, cardiac tamponade, age (more than 70 years old), aortic regurgitation, and shock. Fourteen patients underwent emergent surgery for DeBakey type I acute aortic dissection. These patients were the basis for this reports. Operative mortality was 43% (6/14). Although not statistically significant, there was a trend toward preoperative cardiac tamponade, namely the patients with preoperative tamponade had a poor prognosis. Causes of death were as follows, two patients related to the residual false lumen, two patients to surgical procedure, one patients to ischemic heart and one to mis-swallowing after operation. Among two patients who related to the residual false lumen, one died of rupture of the descending aorta that the clamping was performed during operation and the other occlusion of superior mesenteric artery 43 days after operation. Causes of deaths in patients in relation with surgical procedure were brain death and postoperative bleeding in 1 each. We concluded that the residual false lumen is a risk factor in the peri-operative stage.

Adult↗

PubMed1995

[Changes in intraoperative and postoperative colloid oncotic pressure after open heart surgery especially in relation to non-blood priming or blood priming].

In order to evaluate the colloid oncotic pressure (COP) is useful index of hemodynamics and respiratory recovery after open heart surgery, cardiac index (CI), pulmonary capillary wedge pressure (PCWP), (A-a) Do2 and COP were measured in 34 patients during 48 hours after the cardiopulmonary bypass (CPB). The patients were divided into non-blood priming group: 11 patients and blood priming group (23 patients). In addition, blood priming group divided into two groups, one with dopamine (more than 15 micrograms/kg/min), epinephrine or intraaortic balloon pumping (severe blood subgroup, n = 6) and the other without these treatments after open heart surgery (slight blood subgroup n = 17). The COP levels in the non-blood priming group were significantly higher than those in the blood priming group from aortic cross-clamp to 10 minutes after aortic declamping (p < 0.01). From 1 to 48 hours after CPB, COP in the non-blood priming group and slight blood subgroups was significantly higher than severe blood subgroups (p < 0.05). CI and COP-PCWP levels were significantly higher in the non-blood priming group and slight blood subgroups than those in the severe blood group (p < 0.05). It is concluded that COP is useful index of hemodynamics and respiratory recovery after open heart surgery and our priming system without blood is effective in order to eliminate the blood transfusion.

Aged↗

PubMed1995

[Influence of cardiopulmonary bypass on biological response].

To investigate the influence of cardiopulmonary bypass (CPB) on biological response, we measured the serum level of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and granulocyte elastase (GEL) in 24 patients who underwent elective cardiac surgery and 32 patients who underwent elective gastroenterological surgery. All patients were alive. The serum level of GEL in cardiac patients was significantly higher than that in gastroenterological patients on the 1st and the 3rd postoperative day (P = 0.00008, P = 0.00097 respectively). In addition. there was a significant relationship between CPB time and the serum level of GEL immediately after CPB (r = 0.53, P = 0. 007). That is a reason why higher level of serum GEL in cardiac surgery is due to the bacterial translocation. TNF-alpha and IL-1beta were detected in only :3 patients who underwent over 250 minutes CPB. It is most important to shorten the CPB time in order to decrease the serum GEL and lessen the biological response surgery.

Cardiopulmonary Bypass↗

PubMed1994

Fluid shear stress increases the expression of thrombomodulin by cultured human endothelial cells.

Endothelial cells (ECs) cultured from human umbilical vein were exposed to medium flow in a flow-loading chamber, and changes in thrombomodulin (TM) expression were examined by flow cytometry and enzyme linked immunosorbent assay with monoclonal antibody. The expression of TM antigen was increased time- and shear stress-dependently by flow, and when exposed to a shear stress of 15 dynes/cm2 for 24 hr, it increased to approximately 200% of the stationary control level. Reverse transcriptase-polymerase chain reaction showed that TM mRNA levels in ECs also increased in response to flow. TM mRNA began to increase one hour after the application of shear stress of 15 dynes/cm2 and reached a maximum (approximately 330% of stationary control) after eight hours. These results, demonstrating an up-regulating effect of flow on TM expression in ECs, suggest that shear stress may be an important modulator of intravascular blood coagulation.

Antibodies, Monoclonal↗

PubMed1994

Laminar flow stimulates ATP- and shear stress-dependent nitric oxide production in cultured bovine endothelial cells.

Based on the fact that nitric oxide (NO) production is associated with changes in intracellular cGMP levels and is selectively inhibited by N omega-methyl L-arginine (L-NME), we investigated the shear stress dependency of NO production in endothelial cells (ECs) from its cGMP responses to various shear stress loads. Cultured fetal bovine aortic ECs treated with a phosphodiesterase inhibitor, isobutylmethylxanthine (IBMX; 1 mM), were exposed to a laminar flow of Krebs buffer solution for 5 minutes in a parallel-plate flow chamber and examined for changes in intracellular cGMP levels by radioimmunoassay using an [125I] cGMP kit. Application of flow increased the cGMP levels. The increase was significant in the presence of extracellular ATP (1 microM)(control, 286.1 +/- 43.6; flow, 506.5 +/- 44.9 fmol/10(7) cells; p < 0.001), but not in its absence (control, 256.6 +/- 60.6; flow, 301.5 +/- 91.4 fmol/10(7) cells; N.S.). The cGMP levels increased significantly as the magnitude of shear stress applied increased. Treatment of ECs with a specific inhibitor of NO production, L-NMA (200 microM), completely inhibited the flow-induced increase in cGMP, and L-arginine reversed the L-NMA-induced inhibition, indicating that the increase in cGMP was due to NO produced by the flow. The flow-induced increase in NO production was markedly suppressed when extracellular Ca++ was chelated by adding EGTA to the perfusate. These findings suggest that flow stimulates NO production to increase cGMP levels shear stress-dependently in ECs and that extracellular Ca++ and ATP modulate the effects of flow.

1-Methyl-3-isobutylxanthine↗

PubMed1994

Estimation of remnant liver function before hepatectomy by means of technetium-99m-diethylenetriamine-pentaacetic acid galactosyl human albumin.

To improve the results of hepatectomy in cirrhotic patients, the likely reserve function of the liver was evaluated before surgery. Asialoglycoprotein receptor (ASGP-R) is a hepatic cell surface receptor specific for galactose-terminated glycoproteins. Technetium-99m-diethylene triamine pentaacetic acid-galactosyl human serum albumin (99mTc-GSA) is a newly developed analog ligand to ASPG-R. The probable functional reserve of the remnant liver after hepatectomy was estimated preoperatively as the hepatic binding protein (HBP) concentration specific for ASGP-R on the hepatocellular membrane of the remnant liver. This estimate was based on the effective liver volume rate, obtained by the uptake of 99mTc-GSA. In all, 3 normal volunteers, 3 patients with chronic hepatitis (CH), 9 patients with liver cirrhosis (LC), 2 patients with hepatic cystadenoma, 3 patients with hepatocellular carcinoma (HCC) associated with CH, and 21 HCC patients with LC were studied. The mean value +/- SD obtained for HBP in normal volunteers (three cases) and in patients with mild (four cases), moderate (two cases), and severe liver damage (five cases) were 0.74 +/- 0.03 microM, 0.43 +/- 0.042 microM, 0.31 +/- 0.05 microM, and 0.20 +/- 0.05 microM, respectively. Most of the cases in which the preoperative HBP of the remnant liver was above 0.22 microM had a good postoperative course irrespective of the type of hepatectomy. On the other hand, in subjects with a remnant liver HBP of between 0.22 and 0.11 microM, postoperative severe liver dysfunction occurred in about 50% of cases. In all cases with a remnant liver HBP below 0.1 microM, the prognosis was very poor, indicating that hepatectomy should be avoided. The HBP concentration detected by the 99mTc-GSA study is a very sensitive indicator of changes in the hepatic functional reserve, and the HBP value for the functional reserve of the remnant liver is extremely useful for estimating the liver function before and after hepatectomy.

Adult↗

PubMed1994

The addition of glutathione (YM737) to a crystalloid cardioplegic solution enhances myocardial protection.

The effectiveness of a glutathione preparation, YM737, as a free radical scavenger when added to hypothermic (4 degrees C) crystalloid cardioplegic solution was evaluated in this study. Rabbit hearts were preserved for 3 h in cardioplegic arrest by infusing 20 ml crystalloid cardioplegic solution initially, with additional 10-ml boluses administered every 30 min, while maintaining a myocardial temperature of 10 degrees C. They were then reperfused with Krebs-Henseleit bicarbonate buffer at 37 degrees C in a perfusion circuit for 60 min. The hearts were divided into two groups of six: One in which crystalloid cardioplegic solution was perfused (group 1); and one in which crystalloid cardioplegic solution containing YM737 1 mg/ml was perfused (group 2). The postischemic developed pressure (mmHg) in group 2 was significantly greater than that in group 1 after 60 min of reperfusion, being 44.8 +/- 8.4 versus 87.8 +/- 5.2 in groups 1 and 2, respectively (P < 0.01). Moreover, group 2 exhibited significantly lower postischemic left ventricular compliance after 60 min than group 1 (P < 0.01) and a significantly higher postischemic peak LV dp/dt (mmHg/sec) after 60 min of reperfusion, being 925 +/- 213 versus 1,550 +/- 111 in groups 1 and 2, respectively (P < 0.05). Based on the comparisons of postischemic hemodynamics it was concluded that the addition of glutathione to crystalloid cardioplegic solution does in fact enhance myocardial protection.

Animals↗