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S Murakawa

Publications and source records attributed to S Murakawa.

At least 37 records · Page 2Linked to original sources
PubMed1995

[Noninvasive detection of the limitation of simple cold storage of the heart by myocardial electrical impedance].

The purpose of this study was to determine if graft viability during simple cold storage can be monitored from alteration of myocardial electrical impedance. Twelve anesthetized dogs were underwent rapid cardiac extripation and were placed in simple cold storage. They were divided into two groups according to preserved solution. Group S was preserved in 12 hours in saline. Group U was preserved in 24 hours in the University of Wisconsin (UW) solution. Myocardial electrical impedance was measured serially by use of a LCR meter and analyzed the changes of myocardial resistivity during preservation. Myocardial specimens were taken for myocardial ATP measurement with high-performance liquid chromatography and for water content in two groups. Moreover in order to predict the cardiac function after transplantation in two groups, heterotopic cardiac transplantation in the neck was performed in mongrel dogs and left ventricular (LV) Emax was measured. Myocardial resistivity increased significantly until 5.5 hours in group S, 13 hours in group U. ATP remained above 50% at 5.5 hours in Group S, 13.7 hours in Group U. Resistivity increase rate was over 0.1 omega cm/min in the period ATP remained above 50%. Myocardial water content increased during preservation in group S, but did not in group U. There was no relationship between the increase of resistivity and myocardial water content. LVEmax at 120 min after reperfusion was over 90% of preischemic value in 4 hour preserved heart in saline and 12 hour preserved heart in UW. Measurement of myocardial resistivity during simple cold storage may be feasivle as a monitor of graft viability.

Adenosine Triphosphate↗
PubMed1994

Another approach for aortic valve replacement through left thoracotomy.

We report a 54-year-old man with a history of esophagectomy and retrosternal esophagogastric anastomosis for esophageal cancer through right thoracotomy in whom cardiac failure developed due to aortic regurgitation. He underwent aortic valve replacement through a left thoracotomy with division of two great arteries and their strong traction toward the surgeon by stay sutures. He has been well for 3 years postoperatively in New York Heart Association class I.

Anastomosis, Surgical↗
PubMed1993

[Right ventricular myxoma--case report and review of the literature].

Primary tumors of the heart are rare, with the most common being myxoma, although myxoma of ventricular origin are uncommon. A careful review of the literature showed that 72 patients worldwide had cardiac myxomas located in the right ventricle. A 13-year-old asymptomatic girl with no previous history of cardiac disease was referred to a local hospital for evaluation of a heart murmur detected during a routine medical examination. Right ventricular myxoma was diagnosed and confirmed by echocardiogram, angiocardiography, CT, and MRI, MRI was firstly performed of right ventricular myxoma, and that showed right ventricular myxoma and the myocardium at the same intensity. Surgery was performed by first opening the right atrium. A lobulated mass was visualized through the tricuspid valve. Using a long needle, we confirmed that the wall was attached to the pedicle of the myxoma. Right ventriculotomy was subsequently performed in this region. The mass was passed through the tricuspid valve, and was reseated along with surrounding myocardium but with minimal excision of the right ventricular wall. The excised myxoma weighed 11 g, and had developed a short and small pedicle (5 mm x 5 mm) on the free wall and septum of the right ventricle. The patient recovered uneventfully and was discharged two weeks after the operation.

Adolescent↗
PubMed1993

[Intraoperative assessment of left ventricular function with left ventricular pressure-volume relationships in patients with open heart surgery].

There are few reports on the assessment of the left ventricular function from left pressure-volume relationships intraoperatively in open heart surgery. LV Emax, Ea/Ees and EW/PVA efficiency were assessed intraoperatively by using a left ventricular conductance catheter in patients with aortocoronary bypass. After dobutamine administration (DOB, 10 micrograms/kg/min), LV Emax was increased by 33 +/- 23% during cardiopulmonary bypass (CPB) and 60 +/- 38% after weaning from CPB. Ea/Ees changed from 2.14 +/- 1.36 to 1.08 +/- 0.47 after weaning from CPB with dobutamine administration. EW/PVA efficiency changed from 52 +/- 12% to 66 +/- 10%. The change of LV Emax after dobutamine administration was correlated with the change of LV Emax after weaning from CPB and was correlated with Ea/Ees and EW/PVA efficiency after weaning from CPB. We concluded that measuring LV Emax before and after dobutamine administration during CPB is useful to assess left ventricular contraction clinically.

Aged↗
PubMed1993

[Assessment of left ventricular contraction with LV Emax during cardiopulmonary bypass in patients with open heart surgery].

There are few reports on the assessment of left ventricular contraction during cardiopulmonary bypass (CPB) in open heart surgery. LV Emax is thought to be a load-independent index of left ventricular function. We used a left ventricular conductance catheter to measure LV Emax from "non-working beating heart" during CPB in 16 patients who underwent open heart surgery. During CPB, at 45 minutes after aortic declamping, changes of heart rate with atrial pacing (120/min) did not change LV Emax, but after intravenous dobutamine administration (DOB, 10 micrograms/kg/min) LV Emax increased by 26% (p < 0.01). DOB increased LV Emax in 14 of 16 patients during CPB. These 14 patients were weaned from CPB without difficulty. But in 2 other patients DOB didn't increase LV Emax during CPB. In order to be weaned from CPB, the two patients needed epinephrine and intraaortic balloon pumping. We concluded that change of LV Emax made by intravenous administration of dobutamine is one of useful indexes to assess left ventricular contractility during cardiopulmonary bypass.

Cardiopulmonary Bypass↗
PubMed1992

Biological potency of a fluorinated vitamin D analogue in hypoparathyroidism.

Several in vivo experiments have revealed that a synthesized fluorinated analogue of vitamin D, 26,26,26,27,27,27-hexafluoro-1,25-dihydroxyvitamin D3 (26,27-F6-1,25(OH)2D3) has a higher and longer-lasting biological activity than 1,25(OH)2D3 in calcium regulating actions. We evaluated the biological potency and the availability for clinical use of this compound in hypocalcemia associated with hypoparathyroidism. In an experimental setting, daily administration of 650 pmol/kg of 26,27-F6-1,25(OH)2D3 showed an equivalent effect to that of 3250 pmol/kg of 1,25(OH)2D3 in elevating whole blood ionized calcium levels in parathyroidectomized rats. Furthermore, an additional clinical study demonstrated that 0.5-1.5 micrograms/day of 26,27-F6-1,25(OH)2D3 were considered adequate maintenance doses in various types of hypoparathyroidism and that changes of medication to the same doses of 1,25(OH)2D3 resulted in prompt decline of urinary calcium excretion and of whole blood ionized calcium levels, and in recurrence of symptoms related to hypocalcemia. Although the mechanism responsible for the high potency of this analogue remains unclear, our experience confirms that 26,27-F6-1,25(OH)2D3 has higher biological activities in bone calcium mobilization and is more potent than 1,25(OH)2D3 in correcting hypocalcemia of hypoparathyroidism in a hospital setting.

Animals↗
PubMed1992

[A case of invasive thymoma which had grown in the SVC via left innominate vein through thymic vein].

A 66-year-old male was referred to our department with mediastinal tumor. The chest X-ray and the chest CT showed a large tumor adjacent to pulmonary artery and descending aorta. Cavogram revealed a filling defect of the SVC. He underwent complete resection of the tumor, resection of the SVC and reconstruction of the SVC with ringed PTFE. The main tumor was 12 x 7 cm in size and the tumor in the SVC was 20 x 15 mm in size. Histopathological findings showed a lymphocytic thymoma. Compact invaded nest of tumor cell was found in the innominate vein. The tumor in the SVC was invasive to the intima of the SVC, but its media and adventure were intact. This case is rare among patients with invasive thymoma as far as the growth is concerned.

Aged↗
PubMed1992

[Modified technique for chronic tricuspid regurgitation in rabbits and evaluation of intestinal malabsorption in the chronic stage of this model].

UNLABELLED: One of pathophysiological processes in cardiac cachexia with severe congestive cardiac failure is malabsorption in the intestine. This malabsorption might be caused by high venous pressure in the intestine, following congestive liver due to congestive cardiac failure. However, this has not been proved experimentally yet. In this experiment, rabbits were utilized because their body weights are relatively equal and their life cycle is shorter than that of dogs, for which experimental procedure has been established. Our purpose was first, to establish the technique which can produce tricuspid regurgitation (TR) in rabbits, and secondly, to examine the degree of malabsorption in these animals in the chronic stage of TR. SURGICAL TECHNIQUE: The TR rabbits (n = 4) were provided by means of division of the chordae of the tricuspid valve through the 4th intercostal space in the right thoracotomy. Division of the chordae was performed through the right atrial incision under direct vision while employing total temporary inflow occlusion. The duration of inflow occlusion varied from one to two minutes. RESULT: The mean of the peak right atrial pressure before the procedure was 6.5 mmHg, that just after the procedure was 16.1 mmHg, and that two to four months after the procedure was 17.0 mmHg. The peak right atrial pressure just after the procedure were higher than those before the procedure, and the peak right atrial pressure two to four months after the procedure were also higher than those before the procedure in all rabbits.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

[Preservation of the heart with University of Wisconsin solution--hemodynamic and morphological evaluation in a canine heterotopically transplanted heart].

University of Wisconsin (UW) solution has been reported to extend the safe cold ischemic time in the preservation of the liver, kidney and pancreas. However, there have been few reports of safe cold ischemic time in heart preservation with UW solution. The purpose of this study was to find whether UW solution can extend the safe cold ischemic time in cardiac transplantation in dogs. Heterotopic cardiac transplantation was performed in mongrel dogs after cold ischemic preservation of the hearts with UW solution, ischemic time 8, 16 and 24 hours (Gr.UW8, Gr.UW16 and Gr.UW24, respectively) and with GIK solution, ischemic time 4 hours (Gr.G4) which is considered the safe cold ischemic time in clinical cardiac transplantation. The following was studied: 1) Emax of the LV, myocardial contraction, by pressure-volume curve with the volume measured conductance catheter method, 2) myocardial tissue blood flow of the LV (MTBF), with laser doppler tissue flow meter, 3) serum CPK and electron microscopical evaluation. Emax and MTBF were measured before transplantation and after reperfusion. Their results were expressed as percentage of the values before transplantation. As results, after 120 minutes from reperfusion, Emax was recovered to 94 +/- 13% in Gr.G4, 104 +/- 11% in Gr.UW8, 67 +/- 22% in Gr.UW16 and 66 +/- 16% in Gr.UW24. Emax in Gr.G4 and Gr.UW8 were significantly (p less than 0.01) higher than that in Gr.UW16 and Gr.UW24. After 120 minutes from reperfusion, MTBF was recovered to 90 +/- 19% in Gr.G4, 98 +/- 9% in Gr.UW8, 63 +/- 19% in Gr.UW16 and 61 +/- 6% in Gr.UW24.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine↗
PubMed1991

Pannorin, a new 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor produced by Chrysosporium pannorum.

Pannorin, a naphthopyrone that inhibits 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, the rate-limiting enzyme in cholesterol synthesis, was isolated from a culture broth of Chrysosporium pannorum M10539 by solvent extraction, Bio-Gel P-6 column chromatography and reverse phase HPLC (Silica ODS). Spectroscopic analyses of the compound yielded 4,8,10-trihydroxy-5-methyl-2H-naphtho[1,2-b]pyran-2-one as the proposed structure. Pannorin inhibited HMG-CoA reductase and in vitro sterol synthesis 50% at a concentration of 160 microM.

Animals↗
PubMed1991

[Downhill esophageal varices due to superior vena cava syndrome].

This study examined the incidence of downhill esophageal varices due to SVC syndrome. The presence of downhill esophageal varices was examined by esophagoscopy or autopsy. Downhill esophageal varices were detected in two of nine (22%) patients with SVC syndrome. One case was a 66-year-old male case who and underwent upper lobectomy for lung cancer in September 1985. He developed SVC syndrome due to recurrence in 1986 and died in 1987. Downhill esophageal varices wer in the upper esophagus by esophagoscopy and confirmed by autopsy. The another case was a 61-year-old female who developed carcinoma of the tongue in 1986 and lymph node metastasis to the mediastinum in 1987. Autopsy revealed downhill esophageal varices in the upper and middle esophagus. Eleven cases of downhill esophageal varices due to SVC syndrome reported in Japan were reviewed and discussed.

Adenocarcinoma↗
PubMed1991

[A case of intrathoracic perineurial cyst].

A 67-year-old man was referred to our surgical clinic for evaluation of an abnormal shadow on the chest X-ray examination. CT scan and MRI revealed a tumor in the posterior mediastinum and destruction of the pedicle and intraspinal invagination by the tumor. The tumor in a paravertebral area are linked with a vertebral canal through a destructed intervertebral foramen. MRI showed that the tumor was a cyst which contained fluid. On thoracotomy a hen's egg sized cyst was found in the posterior mediastinum, the cyst was excised. Pathological diagnosis was a perineurial cyst. This case was clearly differentiated from an intrathoracic meningocele and a neurilemmoma microscopically. This case is the first intrathoracic perineurial cyst in Japan.

Aged↗
PubMed1990

Isolation and biosynthesis of 3 alpha-hydroxy-3,5-dihydromonacolin L.

3 alpha-Hydroxy-3,5-dihydromonacolin L acid (acid form), a new compound related to monacolin K (mevinolin), was isolated from the culture broth of a strain of Monascus ruber. The structure of the compound was determined by a combination of physical techniques. 4a,5-Dihydromonacolin L was converted to 3 alpha-hydroxy-3,5-dihydromonacolin L by a cell-free extract of M. ruber in the presence of molecular oxygen. The results demonstrate that the former is the direct precursor in the biosynthesis of the latter.

Ascomycota↗