Search PubMed⌕ Search

Biomedical subjects

S Murata

Publications and source records attributed to S Murata.

At least 163 records · Page 9Linked to original sources
PubMed1995

[Supra-annular mitral valve replacement for a patient with prosthetic valve endocarditis].

Supraanular mitral valve replacement with a 29 mm CarboMedics prosthetic valve was performed for a 58-year-old patient of prosthetic valve endocarditis. He has received mitral valve replacement 2 years ago, and was admitted because of high fever and severe heart failure diagnosed mitral regurgitation due to valve dehiscence. An annular abscess was observed and the new 29 mm CarboMedics prosthetic valve was sutured to the left atrial wall approximately 10 mm above the original annulus in order to secure the firm suturings for valve implantation and to left the infected annulus intact. The patient, however, underwent reoperation because of valve dehiscence from atrial wall 6 months after surgery. Infectious abscess at the native mitral annulau was observed to be completely cured, and a mitral prosthesis was implanted at the annulus. The patient is discharged under satisfactory condition.

Endocarditis↗
PubMed1995

Role of transforming growth factor-beta 1 on platelet-induced enhancement of endothelin-1 production in cultured vascular endothelial cells.

We and other investigators obtained evidence that platelets stimulate endothelin-1 (ET-1) production at both message and protein levels in vascular endothelial cells (ECs), and that platelet-derived transforming growth factor-beta 1 (TGF-beta 1) is responsible for this stimulation. In the present study, we examined the effects of acidification or heat treatment, known to activate latent TGF-beta 1, on the platelet supernatant-induced ET-1 production in cultured porcine aortic ECs. Supernatant of platelets (6.0 x 10(8) platelets/ml) aggregated by adenosine diphosphate contained large amounts of TGF-beta 1, but were almost in a latent form, and the proportion of active TGF-beta 1 in the supernatant was increased markedly in the case of acidification or heat treatment. These treatments also significantly potentiated the supernatant-induced stimulation of prepro ET-1 mRNA expression and the ET-1 release in ECs. Purified TGF-beta 1 also enhanced ET-1 release, dose-dependently, but the enhancement declined at the higher concentrations. Thus, powerful stimulation of ET-1 production by platelet supernatant after acidification or heat treatment cannot be explained only by increments in active TGF-beta 1. The supernatant-induced stimulation of ET-1 synthesis was significantly inhibited by concomitant treatment of TGF-beta 1 neutralizing antibody, but this inhibition was incomplete even at a concentration that abolished TGF-beta 1-induced maximal stimulation. These results suggest that platelet-induced stimulation and subsequent acidification and heat treatment-induced potentiation on endothelial ET-1 production depend closely on release and activation of TGF-beta 1 derived from platelets.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

[Dislodgement of the ringed-graft--a case report].

A 70-year-old man underwent replacement of the distal aortic arch which contained a huge aneurysm using a ringed graft. He died suddenly of hemoptysis 54 months following the operation. An autopsy revealed dislodgement of the spool on the posterior aspect of the aorta. Histologic examination of the dislodged portion of the ring showed complete disruption of the intima and elastic fibers of the media. There were minimal histologic changes in the anterior portion of the anastomotic site. It is postulated that the long, kinked graft might have caused the late ring dislodgement.

Aged↗
PubMed1995

[Spatial and temporal alteration of the dual supply of the hepatic circulation with transient occlusion of the hepatic veins: spiral volumetric CT during arterial portography and arteriography].

To elucidate the contribution of hepatic veins to the blood flow of liver, CT arterial portography and/or arteriography was performed in eight patients having hepatocellular carcinoma with transient occlusion of the hepatic vein and eight without occlusion. In each patient with occlusion of the hepatic vein, CT showed a well-demarcated fan-shaped area of low density during arterial portography and increased density during arteriography in the corresponding area. Hepatic vein occlusion could result in the pooling of arterial blood in the liver parenchyma. Transient segmental hepatic venous occlusion might improve the results of transcatheter arterial infusion and transcatheter arterial embolization for liver tumors.

Adult↗
PubMed1995

[A long survival case of brain tumor considered as a metastatic tumor].

A case of long survival of brain tumor (well differentiated adenocarcinoma) was reported. A 55-year-old man was admitted in January, 1986, because of a one month history of progressive headache, dizziness and gait disturbance. CT scans revealed an enhancing tumor in contact with the falx in the right frontal lobe. The tumor was totally removed. The histopathological diagnosis was that of a well differentiated adenocarcinoma. The primary site of the adenocarcinoma was not detected. No chemotherapy or radiation therapy was given. Four years and 7 months after surgery CT scans demonstrated a recurrent tumor as a bilaterally expanding falx meningioma. Nearly total removal of the tumor was again performed and diagnosed as adenocarcinoma. Examinations to detect the primary site and other metastatic lesions were negative again. On May 1993, the patient died because of the intracranial dissemination of tumor without extracranial lesions. The period from the first operation to his death was 7 years and 5 months. This is a case of long survival of intracranial cancer, which was considered as a metastatic tumor, though the primary site and other metastatic lesions were not detected. The tumor in this case showed the atypical features of a metastatic adenocarcinoma. For example, the primary and recurrent tumors resembled a parasagital or falx meningioma in shape and they grew slowly. Therefore, there is a possibility that the tumor was actually a primary adenocarcinoma, which might have arisen from the embryologically migrated cells of the mucous membrane or from ectopic epithelial cells.

Adenocarcinoma↗
PubMed1995

[Surgical treatment of type A aortic dissection based on the location of the entry].

From 1987 to February of 1994, 42 cases of acute aortic dissection and 31 cases of chronic dissection have been operated in out institution. Our surgical technique for the treatment of aortic dissection is a tubular graft replacement following a resection of the segment of aorta containing the intimal tear. The location of the entry was, therefore, important to determine the extension of graft replacement and to select the circulatory support method during operation. 52%, 33% and 14% of cases in acute aortic dissection had entries in ascending, arch and descending aorta, respectively. Entries of 52%, 32% and 16% of cases in chronic dissection located in ascending, arch and descending aorta, respectively. In cases with the entry in ascending aorta, ascending aorta and partial aortic arch replacement was performed in 12 and 10, respectively, for acute dissection, whereas more extensive graft replacement procedure was selected for chronic dissection including complete arch replacement in three cases and two of them had concomitant Bentall type operation. Likewise, with the entry in aortic arch, partial arch replacement was performed more often in 9 than complete arch replacement in 5 for acute dissection, on the other hand, complete arch replacement procedure tended to be preferable in 6 cases for chronic dissection. For retrograde dissection with the entry in descending aorta, ascending aorta and complete arch replacement were performed in 4 and 6 cases, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

[Esophageal perforation by alkalis--a case report with conservative therapy].

In May 1993, a 59-year-old woman attempting suicide with toilet detergent (1% sodium hydroxide) was hospitalized as an emergency case. She developed sudden high fever (38-39 degrees C) on the 26th admission day. Thereafter diagnosis of left pyothorax due to perforation on caustic esophageal ulcer was made. Subsequent to thoracentesis continuous dranage of the left thoracic cavity ceased the fever after three days. Oral intake began on the 28th and extubation of the dranage was done on the 42nd after admission. Following hospital course of the patient was uneventful and the patient was discharged on the 111th day after admission. Esophagofluoroscopy taken at 6 months after discharge revealed no esophageal stenosis, and the patient returned to full social activities in good health.

Drainage↗
PubMed1995

[Successful cardiac surgery using normothermic cardiopulmonary bypass in an elderly patient with cryoglobulinemia].

The case of 70-year-old woman with cryoglobulinemia who underwent urgent operation for angina pectoris and mitral regurgitation is reported. Three bypass grafts and mitral valvuloplasty were performed under normothermic cardiopulmonary bypass with continuous warm blood cardioplegia. The postoperative course was uneventful. Normothermic cardioplegia requires further study as a technique for managing patients with cold autoimmune diseases such as cryoglobulinemia who require cardiopulmonary bypass.

Aged↗
PubMed1995

[Systemic-pulmonary artery shunt using Golaski graft: trial for measurement of the shunt flow].

For the systemic-pulmonary artery shunt operation, the modified Blalock-Taussig shunt was the first choice for procedure in our institution. Since 1990, Golaski knitted Dacron graft (4 or 5 mm in diameter) was used for the prosthesis. Ex-vivo flow calibration of the electromagnetic flow meter (Nihon Koden, MFV-3100) to Golaski graft showed good correlation between the real flow and value measured by the electromagnetic flow meter. Shunt flow was measured in the consecutive clinical fifteen cases. The shunt flow per body surface area of the patient who required additional shunt operation was 721 ml/min/m2 and one patient in whom the congestive heart failure developed after the shunt operation, had the shunt flow of 3,022 ml/min/m2. The adequate shunt flow in these cases was ranged from 745 to 2,820 ml/min/m2 (mean +/- 1 SD, 1,490 +/- 587.8). Therefore we performed the systemic-pulmonary artery shunt operation using Golaski graft to get the shunt flow of 1,000 ml/min/m2 (approximately a third of cardiac index) for the guide of good results.

Blood Flow Velocity↗
PubMed1995

[Coronary artery perforation after directional coronary atherectomy (DCA)].

Directional coronary atherectomy (DCA) was performed on a 51-year-old man with unstable angina due to a 90% stenosis of the proximal side of the left anterior descending artery (LAD). A coronary angiography after the DCA showed the coronary artery perforation communicating with the pericardial space. He suffered cardiac tamponade and cardiogenic shock, and was taken to the emergent surgical intervention. The both side of the perforation was ligated to control active bleeding and coronary artery bypass grafting to the distal portion of the LAD was performed. It is stated that the incidence of tamponade resulting from vessel perforation after DCA is extremely rare.

Angina, Unstable↗
PubMed1995

[Clinical significance of selective cerebral perfusion with cold blood on the brain protection].

In 42 patients with thoracic aortic disease, a selective cerebral perfusion with 16 degrees C cold blood was applied for the brain protection during the repair of the thoracic aorta. The surgical repair consisted of the replacement of the ascending aorta (9 cases), the ascending aorta and aortic arch (12 cases), the aortic arch (18 cases), and the aortic arch and descending aorta (3 cases). Twenty-two patients of them (52%) required emergency surgery and four patients died due to postoperative complications including visceral organ ischemia (2 cases) and multiple organ failure (2 cases). The mortality rate of this group was 18.2% (4/22 cases). In elective surgical classes, one patient died due to intraoperative coronary embolism. The mortality rate of this group was 5.0% (1/20 cases). No postoperative obvious brain defect was observed except one old patient (85-year-old female) with ruptured aortic arch who already had the brain infarction preoperatively. She died due to multiple organ failure with unconsciousness. Other patients including the patients with long cerebral perfusion (> 180 min) recovered well and returned to normal daily life. The selective cerebral perfusion with cold blood was easy to prepare and demonstrated the superb efficacy of brain protection in the patient.

Adult↗
PubMed1995

[Cerebral infarction after the cardiovascular operation].

From January, 1990 through July 1994, 615 adult patients were undergone cardiovascular operation under the cardiopulmonary bypass. Sixteen patients were suffered perioperative cerebral infarction. The etiology of the cerebral infarction was evaluated on the pre and postoperative brain CT findings by the neurologists. In the 283 coronary artery bypass operations, 4 patients suffered watershed infarction (WS) and 4 cerebral embolism. In the 252 valve operations, one WS and one embolism. In the 80 thoracic aortic operations, 5 WS and one embolism, respectively. The risk factors of WS were the elderly, emergency, the longer operative period, and the longer cardiopulmonary bypass period. The risk factor of the embolism were male, preoperative cerebral infarction, the calcified finding of the ascending aorta by the chest CT. It is important to take preventive strategies against the watershed infarction.

Adult↗
PubMed1994

Species-specific amplification of tRNA-derived short interspersed repetitive elements (SINEs) by retroposition: a process of parasitization of entire genomes during the evolution of salmonids.

Fourteen members of the Hpa I subfamilies of tRNA-derived SINEs in particular salmonid species were isolated from genomic libraries of chum salmon, kokanee, coho salmon, masu salmon, and steelhead. Alignment of the sequences of these 14 members, together with those of 4 members already published, 3 of which were previously demonstrated to have been amplified specifically in certain lineages, revealed the presence of five subfamilies with particular diagnostic nucleotides. The amplification of members of the same subfamily in different salmonid lineages and the amplification of members of different subfamilies in the same salmonid lineage suggest that multiple dispersed loci were responsible for amplification or, alternatively, that SINEs were transmitted horizontally between species. These two possibilities are not mutually exclusive. Our results also indicate that the Hpa I SINEs in salmonids behave like parasites. The amplification of these SINEs is ongoing and continues to shape the evolution of salmonid genomes.

Animals↗
PubMed1994

MRI in subacute combined degeneration.

We describe a patient with clear lesions in the spinal cord on MRI due to subacute combined degeneration. T2-weighted images clearly showed abnormal high signals in the posterior columns, which disappeared on recovery from the disease.

Aged↗
PubMed1994

Aortic arch aneurysm repair using selective cerebral perfusion.

Seventy-seven patients underwent aortic arch aneurysm repair using selective cerebral perfusion from January 1987 to August 1992. Early and long-term results and preoperative and postoperative cerebral function were evaluated. Cerebral function was assessed by the mini mental state-Himeji test and the Wechsler adult intelligence scale. Thirty-six patients had true aneurysms, and 41 had dissection. Hospital mortality for true and dissecting aneurysms was 19.4% and 7.3%, respectively. The 5-year actuarial survival rates for true and dissecting aneurysms were 59.0% and 65.3%, respectively (not significant). There were no significant differences in test scores before or after operation. Repair or replacement of the aortic arch using selective cerebral perfusion is a safe procedure with acceptable hospital mortality.

Aortic Dissection↗
PubMed1994

Safety evaluation of lipase G from Penicillium camembertii.

Lipase G, a partial glycerides eliminating enzyme produced by Penicillium camembertii, was subjected to safety evaluation studies to establish its safety when used as a processing aid in the food industry. The toxicological studies on the enzyme included a 90-day gavage study with rats, a mutagenicity study using bacteria, and a pathogenicity study using mice. The no-adverse-effect level from the 90-day gavage toxicity study was 2000 mg/kg body weight/day for rats. There was no evidence of mutagenic potential. The micro-organism was evaluated for pathogenicity using mice and classified as a non-pathogen. Results indicate that the production and use of lipase G may be regarded as safe for the enzyme production worker and the consumer.

Animals↗
PubMed1994

Effect of clentiazem (TA-3090) with posttreatment on neurologic and histologic disorders of stroke-prone spontaneously hypertensive rats with history of stroke.

After stroke-prone spontaneously hypertensive rats (SHRSP) received a salt-loaded diet to accelerate onset of stroke, the therapeutic effect of clentiazem, a benzothiazepine Ca antagonist, on neurologic and histologic disorders was examined. Treatment with clentiazem (3, 15, and 30 mg/kg) orally twice daily (b.i.d.) for 28 days after the occurrence of stroke reduced neurologic symptoms and histologic changes of brain and kidney in a dose-dependent manner. Acute treatment with clentiazem (15 mg/kg, b.i.d.) administered immediately after stroke for 1 week not only almost completely abolished neurologic symptoms during treatment, but partially improved them even after treatment. Subacute treatment with clentiazem starting 10 days after stroke and continuing for 18 days also suppressed the neurologic signs. Both acute and subacute treatment improved cerebral histology. These results suggest that clentiazem treatment in the acute and subacute phases of stroke is beneficial.

Administration, Oral↗