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Biomedical subjects

M Uematsu

Publications and source records attributed to M Uematsu.

At least 19 recordsLinked to original sources

The role of radiotherapy in the treatment of primary mediastinal seminoma.

Nine patients with primary mediastinal seminoma were treated with radiotherapy. All patients achieved complete response on chest radiography. None of the three patients treated with whole mediastinal irradiation relapsed. Four of the six patients with involved-field irradiation had marginal relapses, suggesting the efficacy of the whole mediastinal irradiation.

Adolescent

Molecular cloning and characterization of the constitutive bovine aortic endothelial cell nitric oxide synthase.

The constitutive endothelial cell nitric oxide synthase (NOS) importantly regulates vascular homeostasis. To gain understanding of this enzyme, a pEF BOS cDNA library of 5 x 10(5) clones was prepared from bovine aortic endothelial cells (BAEC) and screened with a 2.8-kb cDNA BamHI fragment of rat brain NOS. Clone pBOS13 was found to express NO synthase activity when transfected into COS-7 cells. Sequence analysis revealed sequences compatible with binding domains for calcium/calmodulin, flavin mononucleotide, flavin adenine nucleotide and NADPH. The deduced amino acid sequence revealed a protein with a relative mol mass of 133,286, which is 58% homologous to the rat cerebellar NOS and 51% homologous to the mouse macrophage NOS. The amino-terminal portion of the protein exhibits several characteristics peculiar to the endothelial cell NOS. These include a proline-rich region and several potential sites for proline-directed phosphorylation as well as a potential substrate site for acyl transferase. Northern hybridization to mRNA from cultured BAEC revealed an abundant 4.8-kb message, which was not increased by coincubation with tumor necrosis factor alpha, but was markedly increased by exposure to shear stress for 24 h. The unique features of the endothelial cell NO synthase, particularly in the amino terminal portion of the molecule, may provide for novel regulatory influences of enzyme activity and localization.

Amino Acid Oxidoreductases

Sequential appearance of fibronectin, collagen and elastin during fatty streak initiation and maturation in hypercholesterolemic fat-fed rabbits.

To elucidate whether tissue fibronectin increases in the early stages of atherogenesis induced by hypercholesterolemia without mechanical trauma, we investigated sequential changes in the distribution of tissue fibronectin during fatty streak initiation and maturation in the aortas of hypercholesterolemic fat-fed rabbits. The presence of fibronectin was examined on immunoperoxidase stained tissue specimens with the aid of a microscope-photometric technique. Twenty male albino rabbits were used. Cholesterol supplemented chow (1%) was given for 4 weeks (n = 6), 8 (n = 5) or 14 weeks (n = 5). A membrane-like layer positive for fibronectin was observed along the endothelium in the normal aorta. After 4 weeks of the cholesterol-feeding, fatty streaks were initiated in the intima, where fibronectin was more densely accumulated than the normal intima. After 8 weeks of the cholesterol-feeding, fatty streaks were expanding, associated with the dense staining for fibronectin. After 14 weeks, fibronectin was still concentrated in the endothelial layer and also in the superficial areas of the thickened intima, but decreased in the deep areas of the thickened intima where collagen and elastin appeared as bundles. The photometric data of fibronectin supported these visual observations. Thus, fibronectin appeared early and disappeared later in the intima during the process of fatty streak initiation and maturation. These findings suggest that in hypercholesterolemia without mechanical endothelial injury, fibronectin may play an important role in an early process of atherogenesis.

Animals

Contributors of characteristic mitral flow velocity pattern in congestive heart failure--from clinical observations back to experimental validations.

Mitral flow velocity pattern in patients with left ventricular (LV) diastolic dysfunction usually includes decreased peak early diastolic filling velocity (E), slowed deceleration of the early diastolic filling wave and increased peak filling velocity at atrial contraction (A). However, the abnormal mitral flow velocity pattern can be normalized in the presence of concomitant congestive heart failure. In such cases E can be equal to or even higher than normal, its deceleration is normal or faster than normal value, and A can be normal or lower than normal value. Clinical observations in patients with severe heart failure showed that the mitral flow velocity pattern changes with vasodilating therapy, reflecting the changes in the left atrial (LA) to LV pressure difference rather than those in the absolute LA pressure or LV pressure alone. This was validated in the canine study in which levels of LV dysfunction were made by the injection of microspheres into the left coronary artery to study the interrelation among the mitral flow velocity pattern and LA and LV pressures. In this experiment, the changes in the mitral flow velocity pattern could not be explained by the changes in LA or LV pressure alone but was better explained by the changes in the LA to LV pressure difference. Not only LA-LV crossover pressure but also LA compliance seem to be important as determinants of LA pressure level in diastole. In addition to LV relaxation rate, incompleteness of relaxation, elastic recoil and LV passive elastic properties, extracardiac constraint is also considered to be an important determinant of the level of the LV diastolic pressure and hence of the mitral flow velocity pattern at least in the presence of congestive heart failure. Thus, mitral flow velocity pattern is determined by the interaction of LA and LV pressures, both of which are affected by chamber properties as well as loading conditions.

Animals

Doppler assessment of left ventricular diastolic filling pattern during the convalescent stage of acute myocardial infarction. Effects of infarct size and coronary thrombolysis.

Pulsed Doppler echocardiography was used to study left ventricular diastolic filling pattern (LVDFP) over the convalescent stage of acute myocardial infarction (AMI) in 25 patients. Twelve normal subjects served as a control group. The patients were divided on the basis of enzymatically estimated infarct size into 2 groups: 7 as the large AMI group, and the other 18 as the small AMI group. Peak early diastolic filling velocity (E) and the ratio of E to peak filling velocity at atrial contraction (E/A ratio) were determined from the Doppler transmitral flow velocity recordings at 1 and 4 weeks after the onset of AMI. At 1 week E and E/A ratio were significantly lower in the small AMI group compared to the control and the large AMI groups, however, there was no significant difference in E and E/A ratio between the control and the large AMI groups. E/A increased with cumulative CK release among the patients (r = 0.54, p < 0.01). In the following 3 weeks E and E/A ratio decreased only in the large AMI group, and E and E/A ratio at 4 weeks weakly correlated with pulmonary capillary wedge pressure (r = 0.63, p < 0.01 and r = 0.65, p < 0.01) and ejection fraction (r = 0.50, p < 0.05 and r = 0.62, p < 0.01) among the patients. There was no significant difference in E or E/A ratio between patients with and without coronary thrombolysis. Thus, LVDFP in the early convalescent stage of AMI was characterized by low E and E/A ratio in patients with small AMI, however, a "pseudonormalized" pattern was observed in patients with large AMI. The effect of the infarct size on LVDFP diminished in the late convalescent stage of AMI. LVDFP in patients with AMI appears to be influenced by the infarct size and by the time of study. The effect of coronary thrombolysis on LVDFP was not evident throughout the convalescent stage of AMI in this study.

Convalescence

Primary non-AIDS related brain lymphoma. Patterns of failure following radiotherapy.

Thirteen patients with primary brain lymphoma (PBL) were treated with radiotherapy. Three patients also had ocular involvement with retinal masses at initial presentation. All but one patient received conventional whole brain irradiation and, in addition, spinal irradiation, intrathecal methotrexate or orbital irradiation were given in two, two and four patients respectively. The radiation doses for involved sites ranged from 40 to 65 Gy, and for prophylactic sites from 30 to 50 Gy. After radiotherapy, all patients had complete regression of the tumor on computed tomography. Nine patients relapsed, 5 of them with brain recurrence. Two patients had ocular recurrence exclusively as their first relapse. The remaining two relapsing patients had bone lesions. One patient died intercurrently. As a result, only three patients are alive and free of disease after 16 to 36 months and all three received some adjuvant treatment in addition to whole brain irradiation.

Adult

[Long-term results of the Blalock-Taussig shunts].

One-hundred and thirty-six patients received the classical Blalock-Taussig shunts between 1980 and 1990. Their age range at operation was 4 days to 12.8 years and their median age was 13 months. The operative mortality rate was 0.7% (1/136). The survivors were followed up from 1 month to 11.5 years, 5.4 years in average. Twenty-five patients required another shunt and the mean interval to that procedure was 2.4 years (modified Blalock-Taussig 23, classical Blalock-Taussig 2, Glenn 1, internal mammary artery-pulmonary artery shunt 1). Forty-five patients received corrective operations, there were four operative deaths (Fontan 2, Rastelli 2). There were 15 late deaths of which three deaths were not cardiogenic. One year after operation, 91.0% of patients remained in well-palliated condition. At three years after operation, 76.4% of patients continued to be in well-palliated condition. There were twelve neonates in this series. Their age range was 4 to 26 days and their median age was 13 days. There was no operative death. Five patients required second shunt. There were two late deaths. At present, six patients continue to be in well-palliated condition 8 months to 9 years after first operation. Angiographic findings showed the stenotic change of the vascular anastomoses in 49.3% (35/71) of patients. This study suggests that polydioxanone suture (PDS) will be useful for the growth of the anastomoses in Blalock-Taussig operation.

Anastomosis, Surgical

[Evaluation of left ventricular relaxation by mitral regurgitant curve].

To examine whether left ventricular (LV) isovolumic relaxation can be assessed noninvasively using a continuous-wave Doppler technique, we compared Doppler-determined parameters derived from mitral regurgitation (MR) velocity curve with micromanometer-derived indices of LV relaxation, peak negative dP/dt and tau, in 9 patients with MR (5 with dilated cardiomyopathy, 2 with old myocardial infarction and 2 with rheumatic MR). The rate of LV pressure decay (delta P/delta t) at aortic valve closure was calculated from the recordings of MR jet velocities based on the simplified Bernoulli equation. The time constant of LV pressure decay (tD) was determined as the time from the aortic valve closure to the point where the velocity declined by (1/e)1/2. Doppler-determined delta P/delta t correlated well with hemodynamic peak negative dP/dt (r = 0.97, p < 0.001), and tD with hemodynamic tau (r = 0.89, p < 0.005). Thus, we concluded that left ventricular isovolumic relaxation can be noninvasively assessed with a continuous-wave Doppler technique in the presence of mitral regurgitation.

Blood Flow Velocity

[Limited chemotherapy and radiotherapy for stage I-II intermediate or high grade lymphoma of nodal sites or Waldeyer's ring].

Between 1982 and 1988, forty-four patients with stage I-II intermediate or high grade lymphoma of nodal sites or Waldeyer's ring were treated with the protocol of full dose CHOP and irradiation. Two of these patients had B symptoms. Because the early results of the initial standard treatment with 6 cycles of CHOP and 40 Gy of irradiation were excellent with no relapses, the number of cycles of CHOP and total doses of irradiation were gradually reduced in order to make treatment safer. Since 1987, 3 cycles of CHOP and irradiation of 30 Gy has become the new standard treatment for patients without bulky tumor. All but a few of the 44 patients were treated within the range of these two standards. The follow-up period of 44 patients ranged from 20 to 94 months with median of 56 months. Two patients relapsed and died of disease, both of whom had B symptoms at the initial presentation. Another patient with a prior history of liver dysfunction died of complications of CHOP. The remaining 41 patients are currently alive and free of disease. Fifteen of these patients received the new standard treatment with median follow-up of 28 months, and all are alive and well. In the same period, thirteen patients with the same stage, histology and primary sites were treated outside the protocol mainly with radiation alone because of old age or very small lesion. Five of them died of disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult

Molecular identification and comparison of the starch synthase bound to starch granules between endosperm and leaf blades in rice plants.

Normal (nonglutinous) rice plants (Oryza sativa and O. glaberrima) contain more than 18% amylose in endosperm starch, while waxy (glutinous) plants lack it in this starch. In contrast, leaf starch contained more than 3.6% amylose even in waxy plants. SDS-PAGE analysis of proteins bound to endosperm starch granules in the normal plants revealed a single band with a Mr of 60 kd, whereas waxy plants did not exhibit a similar band. The activity of starch synthase (NDP-glucose-starch glucosyltransferase) was completely inhibited by antibody against the 60-kd protein. Thus, we conclude that the 60-kd protein is the waxy protein encoded by the Wx allele, which also plays a role in the synthesis of nonglutinous starch in endosperm tissue. In leaf blades, the proteins bound to starch granules separated into five bands with Mr's of 53.6 to 64.9 kd on SDS-PAGE. Analysis of these proteins by immunoblotting using antiserum against Wx protein and inhibition of starch synthase activity by the synthase antibody revealed that none of these proteins was homologous to Wx protein. We suggest that the synthesis of amylose in leaf blades is brought about by a protein encoded by a gene(s) different from the Wx gene expressed in the endosperm.

Amylose

[A case of left main bronchial rupture due to bronchocath tube].

A 68-year-old woman underwent a right upper lobectomy for lung cancer. After resection, we noticed the left main bronchial rupture due to bronchocath tube (polyvinyl chloride double lumen tube). The lesion of the rupture was repaired by interrupted sutures with 4-0 prolene. Subsequent course of the patient was uneventful. Tracheobronchial rupture is rare complication of intubation with polyvinyl chloride double lumen tube. There are 6 cases of this complication last five years in Japan. The cause and prevention of this complications are described. It is important to use an adequate tube size, to prevent malposition of the tube and overinflation of the bronchial balloon.

Aged

Recovery of circadian rhythm of plasma cortisol levels after a 3-day trip between Tokyo and San Francisco.

The objective of the present study is to investigate the change in the circadian rhythm of plasma cortisol levels following a 3-d trip and a westbound return flight from San Francisco (SFO) to Tokyo. Six healthy male students volunteered for the project. Plasma cortisol levels were monitored 4 times daily for 13 d during the experimental period. In Tokyo, the baseline pattern of cortisol concentrations showed the classical diurnal profile. During the 50-h stay in SFO, phase advancement of 8 h was observed for the initial 32 h. This was followed by a disturbance in the profile for the remaining 18-h period. After returning to Tokyo, the subjects exhibited the original diurnal pattern beginning Day 1. However, complete resynchronization was not apparent until Day 4 after the return.

Adaptation, Physiological

[A case of localized pleural mesothelioma].

A case of localized pleural mesothelioma is reported. A 49-year-old man was operated for coin lesion detected on routine chest X-ray. A tumor arose from the visceral pleura of right lower lobe and was pedunculated. Size of the tumor was 4 x 3 x 3 cm. Cut surface of the tumor was solid and yellowish white. Pathological diagnosis was fibrous type of the pleural mesothelioma. The patient is well and has no sign of recurrence for three years. There are 123 cases of localized pleural mesothelioma including our case in Japan. Five in 78 cases which was diagnosed to be benign histologically at operation, had recurrence later. It is important to follow up strictly for long term.

Humans

[Non-Hodgkin's lymphoma of the Waldeyer's ring: the treatment results of the past 22 years and the significance of CHOP].

From 1966 through 1988, 124 patients with non-Hodgkin's lymphoma of the Waldeyer's ring were treated. Seventy patients were male, and 54 were female. Age ranged from 5 to 81 years with a median value of 53 years. Pathological slides were reviewed and reclassified according to the Working Formulation. Diffuse large cell type was most common (53%). Since 1981, CHOP has been incorporated into the treatment including stage I and II patients. During these 22 years, new imaging modalities have developed, and an upstage rate by using those modalities has increased from 5% to 9%. In order to make the comparison meaningful, we used clinical stage determined at the day of the first visit. Fifty-one patients were clinical stage I, 64 were stage II, seven were stage III, and two were stage IV. B symptom was seen in 8 patients. Relapse developed in 45 patients (41%) out of 111 who achieved complete remission, and distant relapse was most frequent (89%). Salvage therapy was successful in only three patients of the 45 relapsed patients. Overall 5-year freedom from relapse (FFR) were 38% for the patients treated until 1980, and 69% for the patients treated thereafter (p less than 0.01). Addition of CHOP to radiotherapy has increased 5-year FFR of the stage II patients from 31% to 81% (p less than 0.01). In stage I, 5-year FFR was 71% in the patients treated with CHOP and radiotherapy, and it was 27% treated without CHOP. But the difference has no statistical significance, and we can not rule out the presence of selection bias.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent

Doppler echocardiographic quantitation of cross-sectional area under various hemodynamic conditions: an experimental validation in a canine model of supravalvular aortic stenosis.

The hemodynamic effects on cross-sectional area calculated with the continuity equation were assessed in canine experiments. In 13 open chest dogs, 46 supravalvular aortic stenoses were created by aortic root banding. The cross-sectional area of the stenosis was calculated by Doppler echocardiography with application of the continuity equation before and after the following hemodynamic interventions: protocol 1, atrial pacing at 90, 120, 150 and 180 beats/min after sinus node crush; protocol 2, preload reduction by mild and severe clamping of the inferior vena cava; and protocol 3, afterload augmentation by mild and severe clamping of the descending aorta. In each observation, a dimension of the stenosis was directly measured by two-dimensional echocardiography, and the cross-sectional area was determined as a reference standard. As a result of the hemodynamic interventions, significant changes were observed in stroke volume and pressure gradient (protocol 1), in cardiac output, stroke volume and pressure gradient (protocol 2) and in heart rate, cardiac output and pressure gradient (protocol 3). Despite these changes in hemodynamic variables, the Doppler-derived cross-sectional area showed no significant change for a given stenosis. In addition, areas calculated with the continuity equation (x) agreed well with those determined by two-dimensional echocardiography (y) (r = 0.96, p less than 0.001, y = 0.97x + 0.02, SEE = +/- 0.06 cm2). Thus, it is concluded that Doppler echocardiography with application of the continuity equation accurately predicts the stenotic cross-sectional area over a wide range of hemodynamic conditions in supravalvular aortic stenosis.

Animals

Transient global amnesia and Raynaud's phenomenon in scleroderma.

Transient global amnesia (TGA) is a well-recognized clinical entity, but its pathophysiology and prognosis have remained arguable. We reported that a 63-year-old woman with scleroderma developed two TGA episodes. The patient sometimes suffered from headaches when Raynaud's phenomenon appeared in her fingers, but she did not experience further cerebrovascular events. This case suggests that the unique clinical presentation of this syndrome may result from an ischemic event, possibly triggered by a vasospastic mechanism like Raynaud's phenomenon.

Amnesia

Coping styles to basic disorders among schizophrenics.

Coping efforts to subjectively experienced basic disorders were investigated by self-report in 60 chronic schizophrenics in Japan, and the relationships to clinical and demographic variables, intelligence, personality, and attitude toward their illness were analyzed. Self-reports on coping efforts were obtained for more than half of all subjectively experienced basic disorders, and the predominant technique was reported to be the approach oriented towards problem-solving. Within each coping style, the behavioral change, divertive problem-solving approach correlated negatively with hospitalization and symptoms, and the struggle, problem-solving efforts without any effective results correlated positively with symptoms. Suggestions regarding integration of these self-efforts into psychosocial treatment of schizophrenia are discussed.

Adaptation, Psychological

Quantitative color flow imaging to measure the two-dimensional distribution of blood flow velocity and the flow rate.

A quantitative Doppler color flow imaging was employed to measure the two-dimensional distribution of blood flow velocity and flow rate in a large vessel. Regional blood flow velocity was determined by converting the color intensity at the respective pixel into corresponding flow velocity and correcting the flow velocity for spatial ultrasound beam incident angle. Instantaneous flow rate was determined precisely from the image of velocity distribution on the cross-section of the flow tract in a steady flow model circuit. In clinical application, the differences in phasic changes in two-dimensional velocity distribution in the ascending aorta, between normal subjects and the patient with aortic regurgitation, were clearly depicted. The quantitative color flow imaging may have great potential to determine noninvasively and real-timely the two-dimensional distribution of flow velocity as well as flow rate in a large vessel.

Aortic Valve Insufficiency