Biomedical subjects

Y Shimamura

Publications and source records attributed to Y Shimamura.

At least 55 records · Page 3Linked to original sources

PubMed1994

A randomized trial of intrahepatic arterial infusion of 4'-epidoxorubicin with Lipiodol versus 4'-epidoxorubicin alone in the treatment of hepatocellular carcinoma.

We conducted a prospective randomized trial to evaluate the efficacy of Lipiodol in intrahepatic arterial infusion chemotherapy for patients with hepatocellular carcinoma (HCC). A total of 38 patients with unresectable HCCs and underlying cirrhosis were entered in this trial, and 36 of them were evaluable. Every 4 weeks, 17 patients received 70 mg of 4'-epidoxorubicin (epirubicin) alone (group A), whereas 19 patients received a Lipiodol emulsion containing the same dose of epirubicin (group B) through the hepatic artery. A tumor response (CR+PR) was observed in 12% of group A patients and in 42% of group B patients. The group B patients showed a significantly higher response rate than the group A patients. There was a tendency for an increased duration of survival (P = 0.09) in the group B patients. These results suggested that the infusion of the Lipiodol emulsion with epirubicin was more effective than epirubicin alone for the treatment of these patients with HCC.

Aged↗

PubMed1994

Pharmacokinetic properties of E3810, a new proton pump inhibitor, in healthy male volunteers.

E3810 is a new H+,K(+)-ATPase inhibitor with a substituted benzimidazole, which is under clinical investigation for peptic ulcer treatment in Japan and the USA. Three separate studies were conducted to evaluate the safety and to establish the pharmacokinetic profile of E3810 after oral administration to healthy male subjects. E3810 was administered as: single oral doses (1, 3, 10, 20, 40 and 80 mg) in fasting conditions, a single oral dose (20 mg) after a meal and repeated oral doses (20 and 40 mg) once daily for 7 days. The concentrations of E3810 and its metabolites in plasma and urine were determined by HPLC methods with UV detection. E3810 was generally well tolerated by all subjects. In the single-dose study, Cmax and AUC increased with increasing doses in the dose range examined. The mean plasma half-life was about 1.0 hour and was dose-independent. The apparent oral clearance of E3810 ranged from 4.37 to 8.40 ml/min/kg. No significant deviation from linear pharmacokinetics was observed. Approximately, 30% of a dose was excreted into the urine as thioether carboxylic acid-E3810 and its glucuronide. The mean serum protein binding was 96.3%. No effect of food intake on the Cmax and AUC was observed while tmax after a meal was 1.7 hours longer than that in the fasting conditions. No appreciable change in drug pharmacokinetics was observed during repeated oral dosing of E3810.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed1994

[Surgical treatment of infective endocarditis in patients with congenital heart disease].

From 1981 to March 1993, 21 patients underwent surgical treatment for infective endocarditis (IE) associated with congenital heart disease (CHD). We evaluated the surgical results with regard to various factors, including microorganisms, pre- and postoperative complications, the correlation between CHD and the infective focus in the valve, the operative methods and surgical results. Underlying CHD included ventricular septal defect (VSD) in 15 (71.5%), persistent ductus arteriosus (PDA) in 2 (9.5%), tetralogy of Fallot (TF) in 2 (9.5%) and incomplete endocardial cushion defect (IECD) in 2 patients (9.5%). Microorganisms were detected in 71.4% of the patients, including streptococcus in 11 patients (52.4%), staphylococcus in 2 (9.5%) and gram-negative bacillin in 2 (9.5%). Embolism or infarction was noted preoperatively in 5 patients (23.8%) and was located in the kidney in 4 patients, the leg in 2, and in the liver and lung in 1 patient each. Among 15 patients with VSD, the lesion of IE was seen on the left side of the heart in 11 patients, on the right side in 3 and on both sides in 1. The PDA and IECD were seen on the left side in 2 patients each, but the IE focus of the 2 patients with TF was on the left side in one and on both sides in the other patient. Aortic valve replacement was performed in 17 patients, mitral valve replacement in 3, tricuspid valve plasty in 2, tricuspid annuloplasty in 1 and pulmonary valve resection in 2 patients. The operative mortality was 4.8% and there were no reoperations or late deaths.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

[Curative report of post sternotomy mediastinitis due to bacterofungal infection].

We describe a 72-year-old patient with mediastinitis caused by Methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans after median sternotomy who was successfully treated with wound closure with pectoral musculocutaneous flap and closed continuous mediastinal irrigation. The irrigation device consisted of two pairs of irrigation and suction tubes which placed upper and lower half of mediastinum respectively, in which high rate irrigation technique (200 ml/h) was employed using 0.01% of Vancomycin hydrochloride as a base agent and additional 0.1% of Povidone-iodine in early phase and 0.01% of Fluconazole in late phase. After 12-days irrigation, the drainage culture turned negative and the wound was healed and tomographically granulated. High rate irrigation with sufficient concentration of antimicrobial agents selected according to each organism sensitivity could eliminate redundant irrigation and contribute to avoid antimicrobial toxication. We experienced also another four cases (two caused by MRSA, two caused by Serratia liquefaciens) treated successfully with this technique. These results led us to believe that continuous mediastinal irrigation technique could be carried out with safe and effectiveness so far as high rate irrigation with low concentration of Povidone-iodine is employed.

Aged↗

PubMed1993

Distal aortic arch aneurysmectomy and coronary revascularization through a left thoracotomy.

A successful single operation of a distal aortic arch aneurysm and coronary artery disease through a left lateral thoracotomy using a simple hypothermic retrograde cerebral perfusion technique for cerebral protection in a 64-year-old man is reported. During ventricular fibrillation accompanying cooling to 15 degrees C, a left internal thoracic artery was anastomosed with the left anterior descending coronary artery, and the aneurysm was replaced with a patch during hypothermic retrograde cerebral perfusion.

Aorta, Thoracic↗

PubMed1993

[A case report of malignant mesothelioma].

A case of successful surgical removal of a primary malignant pericardial mesothelioma was reported. The patient was a 79-year-old man with a complaint of dyspnea at rest. Chest X-ray study showed enlargement of upper mediastinum. Echocardiogram, computed tomography and MRI revealed a giant mass occupying the pericardial space anterior to the heart with marked pericardial effusion. The right ventricle was severely compressed with this tumor. Total resection of the tumor was achieved because the tumor was localized without invading surrounding tissue. The tumor was 17 x 12 x 10 cm in size and 900 g in weight. Rare growth fashion as a distinct isolated mass was a key of successful outcome.

Aged↗

PubMed1993

[A case report of BWG syndrome in an elderly patient performed with mitral valve replacement 11 years after single CABG].

A 46-year-old female who had undergone single CABG for BWG syndrome 11 years ago was referred to our hospital for paroxysmal atrial fibrillation. The roentgenogram showed slightly cardiomegaly and the enlargement of LA. Ischemic changes of ECG appeared at I, aVL, V5, V6, as inverted T wave, and low voltage R wave at V1-V4, but non Q wave. The thallium-201 emission computed tomogram at exercise revealed poor perfusion at apical region without redistribution pattern. Catheterization showed mitral regurgitation (grade III), big right coronary artery (RCA) arising from aorta, rich collateral to poor left coronary artery (LCA), and bypass graft was obstructed. The proximal end of LCA was closed, and didn't arise from both pulmonary artery and ascending aorta. In this cases, MVR only without re-CABG to LCA was selected and performed. Postoperative course was uneventful. The result of this case suggested that MVR was an effective surgical procedure for MR of BWG syndrome in the adult case and it was better to add CABG to LCA as much as possible if the ischemic region was large.

Coronary Artery Bypass↗

PubMed1993

[Late malfunction of the Björk-Shiley valve prosthesis due to Delrin disc defacement].

A 55-year-old woman eighteen years after mitral valvular replacement with Delrin disc Björk-Shiley valve prosthesis underwent a reoperation of prosthetic valve replacement for the prosthetic malfunction due to disc defacement. The patient suffered from faintness and vertigo at rest. An echocardiographic examination showed a moderate mitral insufficiency with a normal disc movement. Precise examination on the removed prosthesis revealed accelerated defacement of disc margin which made the ring-disc clearance up to 0.35 mm and strut-shaped groove formation on the inlet surface of the disc occluder. These findings suggested a pronouncedly earlier disc wear than predicted by Björk and co-workers. We concluded, therefore, that a patient undergone a valve replacement with Delrin disc Björk-Shiley valve should be examined periodically by echocardiography even though being without any symptoms.

Female↗

PubMed1993

Temporary redistribution of hepatic or pancreatic blood flow by vascular occluders during intra-arterial chemotherapy for carcinoma of the liver or pancreas.

Surgically placed inflatable vascular occluders temporarily increased or restricted the target volume for intra-arterial therapy for tumors in the liver and pancreas. Proximal occlusion of the common hepatic artery directed retrograde flow from the cannulated gastroduodenal artery into a variant left hepatic artery in one patient with carcinoma of the liver. Occlusion of the distal splenic artery and common hepatic artery after distal gastrectomy with cannulation of the left gastric artery gave selective perfusion of the tumor-bearing pancreatic head in three patients. The occlusions had no untoward effects and the regional infusions seemed to retard local tumor growth.

Catheterization↗

PubMed1993

Pharmacokinetics of E2020, a new compound for Alzheimer's disease, in healthy male volunteers.

E2020 is a new cholinesterase inhibitor with a novel chemical structure, which is under clinical investigation for use in Alzheimer's disease in Japan and the USA. Three separate studies were conducted to evaluate the safety and to establish the pharmacokinetic profile of E2020 after oral administration to healthy male subjects. E2020 was administered as: (1) single oral doses (0.3 mg, 1 mg, 2 mg, 5 mg, 8 mg and 10 mg) in a fasting condition, (2) a single oral dose (2 mg) after a meal and (3) repeated oral doses (2 mg once daily for 21 days). The concentrations of E2020 and its metabolites in plasma, serum, urine and feces were determined by HPLC methods with UV detection. E2020 was generally well tolerated by all subjects. In the single-dose study, there was a linear relationship between dose and mean AUC. The mean plasma half-life was about 50 hours and was dose-independent. The total clearance and renal clearance of E2020 were also dose-independent and the mean values after 10 mg dosing were 9.7 l/hour and 0.86 l/hour, respectively. The cumulative total urinary and fecal excretion of the sum of unchanged E2020 and its metabolites at 264 hours after the administration of the single 10-mg-dose was 36.1% and 8.6% of the dose, respectively. The mean serum protein binding was 92.6%. No effect of food intake on the pharmacokinetics was observed. Evaluation of the mean trough levels and AUC0-24 of E2020 indicated that a steady-state was achieved after approximately 2 weeks of daily dosing.

Adult↗

PubMed1993

[Scintigraphic comparison of graft patency between the left internal thoracic artery and saphenous vein graft after coronary bypass surgery].

Graft patency after coronary bypass surgery (CABG) was evaluated with stress 201-thallium scintigraphy (stress 201Tl) in 26 cases, including 13 cases using the left internal thoracic artery (LITA group) in situ and 13 cases with saphenous vein graft (SVG group). All of them had effort or unstable angina caused by LAD lesion without apparent infarction. Stress 201Tl using a symptom-limited, graded bicycle exercise test was performed before CABG and 1 month, 6 months to 1 year, 1 year to 1.5 years after surgery. Five tomographic images including the apical side of the area fed by the bypass anastomosed to LAD in short axial sections were picked out and piled up. Fan-shaped ROI was made on this area and % Tl uptake was calculated using the following formula. 201Tl counts in ROI--Background counts/Maximum counts--Background counts x 100 (%) The normal % Tl uptake calculated in the control group (n = 11) in this ROI was 68.2 +/- 4.8%. Preoperative % Tl uptake showed 49.3 +/- 0.2% in the LITA group and 54.3 +/- 13.2% in the SVG group. % Tl uptake of the SVG group 1 month after CABG was slightly higher than that of the LITA group, (62.0 +/- 7.0% vs. 56.3 +/- 7.6%). However 6 months to 1 year after, % Tl uptake of the LITA group increased to 60.8 +/- 6.4%, inspite of a tendency on the decrease of that in the SVG group, (59.0 +/- 8.5%), and further more, 1 year to 1.5 years after CABG, increased to 62.3 +/- 5.1% near the normal % Tl uptake of the control group and the SVG group decreased to 58.8 +/- 6.8%. This result suggested that arterial in situ bypass graft might have an auto-regulation and "growing property" corresponding to flow demand, and this helps the excellent long-term patency of arterial bypass grafts.

Adult↗

PubMed1993

[Newly-developed catheter for cardio-renal assist during intraaortic balloon counterpulsation].

A new catheter was developed for the cardio-renal assist during intra-aortic balloon counterpulsation. The catheter consists of both a large balloon of conventional IAB (TMP balloon) located at the distal end of the catheter and an additional small balloon 10 cm distant from the large balloon with common lumen and single shaft. Experimental study was carried out in the mock circulatory system simulating the descending aorta employing a conventional IAB catheter as a control. It was demonstrated that the flow in the mid portion between both balloons could be increased maximally by as much as 28% of that of the control under the continuous flow and 214% under the pulsatile flow. The double balloon catheter was considered to improve the renal perfusion as well as the coronary perfusion.

Assisted Circulation↗

PubMed1993

Debulking surgery and arterial embolization for unresectable liver cancer.

Hepatocellular carcinomas measuring less than 5 cm in diameter became completely necrotic after arterial chemoembolization with Lipiodol, doxorubicin, and gelfoam more often than larger lesions. In 60 patients, we surgically debulked large unresectable tumors, with the aim of subsequently embolizing residual small tumors transarterially. Forty-seven patients were actually embolized. The rate of major non-fatal complications was similar to that seen after radical resections, but the hospital mortality rate was 30%, as compared with 4%. Stage I disease, including non-embolized patients and hospital mortality, had an estimated 5-year survival rate of 27%. This result approached that obtained after curative resections, and was better than that seen after embolization only. Stage II disease had no five-year survivors and its survival curve was intermediate, lying between those of curatively resected and embolization patients. No stage I patients with tumor growth in the portal trunk or lobar branches survived for 2 years. The results warrant further study of this treatment strategy.

Adult↗

PubMed1993

[Blood purification after aorto-coronary bypass grafting for dialysis patients].

Four dialysis patients received aorto-coronary bypass grafting (CABG) at Fukuyama cardiovascular hospital from April 1989 to March 1992. We employed continuous ambulatory peritoneal dialysis (CAPD) in two cases, hemodialysis with extracorporeal ultrafiltration method (ECUM + HD) in one case and hemodiafiltration with continuous veno-venous hemofiltration (CVVHF + HDF) in one case for perioperative management. In each cases, intermittent HD was undergone during 4 days before operation. Intraoperatively, HD was used together with extracorporeal circulation. Blood pressure in the postoperative course changed more frequently in CAPD cases than ECUM + HD or CVVHF + HDF case. Especially, CVVHF + HDF stabilized the movement of circulation and kept balance of serum BUN, Cr after the operation (BUN; 27.2 +/- 6.3, Cr; 5.0 +/- 0.6). We concluded that CVVHF + HDF would be the most favorable method to maintain the fluid balance stably for the uremic patients after CABG.

Adult↗

PubMed1993

[A case report--successful surgical treatment of prosthetic aortic valve detachment with enlargement of sinuses of Valsalva caused by the recurrence of aortitis].

A successful operation on a 49-year-old female with aortitis syndrome associated with prosthetic aortic valve detachment was reported. Aortic valve replacement using SJM 25A had been performed for aortic regurgitation caused by aortitis. Though her C-reactive protein (CRP) was kept between (+/-) and (2+) with prednisolone administered, general fatigue suddenly appeared 4 years after the first operation. The blood sedimentation rate was 65 mm/30 min and CRP was (4+), and the echocardiography showed abnormal movement of the prosthetic valve with perivalvular leakage on admission. Aortography showed the valve detachment and abnormal movement due to enlargement of sinuses of Valsalva, one of which was transformed as a diverticulum and projected into Left ventricular cavity with moderate leakage. After the inflammation was well controlled, she was operated upon. Dilatation of sinuses, perforation of intima around the prosthetic valve were recognized as left ventricular-aortic discontinuity, but ascending aorta was not enlarged. So the prosthetic valve was suspended below coronary ostia with transmural mattress sutures from right atrium. Postoperative course was uneventful. The postoperative aortography revealed only trivial perivalvular leakage without abnormal movement of the valve. This was a rare case of the valve detachment in the aortitis patient.

Aortic Arch Syndromes↗

PubMed1992

Simple hypothermic retrograde cerebral perfusion during aortic arch replacement. A preliminary report on two successful cases.

We recently found that hypothermic retrograde cerebral perfusion can be performed by simply elevating the central venous pressure in Trendelenburg's position while the aortic arch is open. In this technique, with an occlusion balloon in the descending aorta, deep hypothermic perfusion of the lower half of the body is performed as oxygen-rich venous blood supplies the brain. Two successful cases are reported: one of dissecting aortic aneurysm, DeBakey type II, with a true aortic arch aneurysm, in a 53-year-old woman, and one of acute aortic dissection, DeBakey type I, in a 53-year-old man. With the brain under retrograde perfusion at a rectal temperature of 15 degrees C and a central venous pressure of 15 mm Hg, replacement of the ascending to the descending aorta in the former case and to the proximal aortic arch in the latter case was successful. Cerebral circulatory arrest times were 81 and 65 minutes, respectively. No neurologic deficit was found postoperatively. It is suggested that this simple technique protected the brain for a long period of cerebral circulatory arrest during the aortic arch operation by supplying it with oxygen and simplifying the operative procedure.

Aorta, Thoracic↗

PubMed1992

[Simple hypothermic retrograde cerebral perfusion for brain protection during aortic arch surgery].

We have recently found that retrograde cerebral perfusion can be performed by simply elevating central venous pressure to 15 mmHg in the Trendelenburg position when the aortic arch is open during aortic arch surgery. During deep hypothermic (15 degrees C) perfusion of the lower half of the body with the descending aorta occluded, and with single cannulation of the right atrium for drainage, oxygen-saturated venous blood perfuses the brain retrogradely, supplying it with oxygen. This method renders clamping of the aortic arch and the arch vessels unnecessary. Eleven cases of aortic arch aneurysm (9 males, 2 females; 5 true aneurysms, 5 dissecting aneurysms, one combined aneurysm; mean age, 63 years) were operated using this technique, whose clinical significance was then evaluated. Median sternotomy was performed in 4 cases, left thoracotomy in 7. Patch replacement was performed in 2 cases and graft replacement in 9 cases (the proximal arch in 2, the whole arch in 2, the distal arch in 5). In two cases coronary artery bypass surgery using the internal thoracic artery was performed simultaneously via lateral thoracotomy. Operation time was 517 +/- 139 min, pump time was 211 +/- 34 min, cardiac arrest time was 84 +/- 34 min and the lowest rectal temperature was 15.7 +/- 1.1 degrees C. In the venous return, PO2 was 188 +/- 136 mmHg, and SO2 97.5 +/- 2.9%, the respective values in the retrogradely perfused blood in the aortic arch being 46 +/- 12 mmHg and 68.8 +/- 18.8%.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1991

Coagulopathy in chronic subdural hematoma.

Coagulation factors were studied in 30 fluids aspirated from 25 patients with chronic subdural hematoma. Compared with the normal range for plasma, the hematoma fluids demonstrated a marked reduction in factors II, V, VII, VIII, and X, moderate reduction of factors IX and XI, and slight reduction of XII. Factor VII and IX inhibitors were not present or negligible. Activated protein C and antithrombin III were decreased and fibrinopeptide A was markedly increased. No case had a basic disorder causing these abnormal data spontaneously. The decrease in activated protein C possibly caused the marked reduction of factor VIII, therefore the intrinsic and extrinsic clotting pathways were affected differently. The results show excessive activation of coagulation, predominantly via the extrinsic clotting pathway in hematoma, suggesting its importance in the growth of chronic subdural hematoma.

Aged↗