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Biomedical subjects

S Takao

Publications and source records attributed to S Takao.

At least 145 records · Page 8Linked to original sources

[Intraperitoneal chemotherapy in gastric cancer with peritoneal metastasis using totally implantable peritoneal access system].

Fifteen patients with peritoneal metastasis of gastric cancer were treated with mainly ip-ETP (Etoposide: i.p., THP-ADM: i.v. and CDDP: i.p.) or other drugs by the use of a totally implantable peritoneal access system. In principle, intraperitoneal drug delivery was carried out every two weeks. CDDP was administered into the intraperitoneal cavity with intravenous sodium thiosulfate delivered simultaneously to protect against cisplatin-induced nephrotoxicity. RI-scintigram showed that the intraperitoneal catheter was fully useful even six months after the operation. As a result, performance status has been improved in 12 out of 15 cases, and ascites disappeared in 3 out of 6 cases with same. Ten cases have been alive for more than 6 months after operation. There have been no severe complications (e.g., nephrotoxicity or myelosuppression) even in the cases treated at frequent intervals for more than 8 months. The findings in this study indicated that ip-ETP using totally implantable peritoneal access system is beneficial for advanced gastric cancer with peritoneal metastasis.

Adult↗

[Two-route chemotherapy under AT-II induced hypertension using totally implanted injection port system in liver metastases derived from digestive cancers].

Two-route chemotherapy (TRC) with intraarterial infusion of cis-diamminedichloroplatinum and intravenous infusion of sodium thiosulfate was carried out on 8 cases of digestive cancer with liver metastases, using totally implanted injection port system. The metastases occurred from gastric cancer in 3 cases and from colonic cancer in 5 cases. Computed tomography and/or ultra-sonography revealed an overall response rate of 50% (4/8). Complete response (CR) was obtained in two cases. The therapy was repeated 12 times in one case of gastric cancer with multiple liver metastases and 5 times in another rectal cancer with a solid metastatic tumor. In the latter case, a right hepatic lobectomy was performed thereafter. The histology of the hepatic tumor showed mucin lakes and necrotic lesions, and no viable cancer cells were observed. This mode of chemotherapy was therefore considered a useful measure for the treatment of liver metastases derived from digestive cancers. Furthermore, no serious side effects occurred.

Adult↗

[Silent severe tricuspid regurgitation: a study by Doppler echocardiography].

Sixty-eight patients with severe tricuspid regurgitation proven by right ventriculography were examined using pulsed and continuous wave Doppler echocardiography and color Doppler flow imaging. Among the 68 patients, there was no tricuspid regurgitant murmur in 16 (24%) in whom laminar regurgitant flow signals were demonstrated by pulsed Doppler echocardiography. The area in which laminar flow was detected ranged from 8 to 46 mm2 (mean 19.5 +/- 9.8 mm2). The peak velocities in patients without regurgitant murmurs as measured by continuous wave Doppler echocardiography ranged from 1.1 to 1.9 m/sec (mean: 1.61 +/- 0.21 m/sec). Laminar regurgitant flow signals were obtained in six; and turbulent regurgitant flow signals in 46 of 52 patients with tricuspid regurgitant murmurs, and their peak velocities ranged from 1.7 to 5.1 m/sec (2.80 +/- 0.78 m/sec). The peak velocities of the regurgitant flow signals in patients without tricuspid regurgitant murmurs were significantly lower than those in patients with regurgitant murmurs (p less than 0.01). In six patients with laminar regurgitant flow signals and regurgitant murmurs, the areas of laminar flow signals ranged from 3 to 12 mm2 (mean 7.0 +/- 3.5 mm2) and were smaller than those of patients without regurgitant murmurs (p less than 0.001). A characteristic candle flame pattern of regurgitant flow signals was observed in all patients without murmurs. Thus, the absence of a tricuspid regurgitant murmur results from laminar regurgitant flow signals of low velocity and this is characterized by a candle flame pattern using color Doppler flow imaging.

Adolescent↗

[Doppler techniques in the detection of valvular regurgitation: their value and limitations].

To evaluate the clinical value of various Doppler techniques in detecting valvular regurgitation, we compared the sensitivity, timing and duration of regurgitation, and the peak velocity of regurgitant signals among conventional pulsed Doppler, color Doppler, continuous wave Doppler and HPRF Doppler echocardiography. 1. Sensitivity of Doppler techniques in detecting mitral regurgitation: Among fifty patients with mitral regurgitation confirmed by left ventriculography, mitral regurgitation was detected in 48 (96%) using color Doppler and pulsed Doppler echocardiography; in 41 (82%) by HPRF Doppler; and in 37 (74%) by continuous wave Doppler echocardiography. In 103 consecutive normal volunteers, mitral regurgitant signals were detected in 46 (45%) by color Doppler, in 39 (38%) by pulsed Doppler, in 16 (16%) by HPRF Doppler, and in 8 (8%) by continuous wave Doppler echocardiography. 2. Timing and duration of regurgitant signals: To assess the timing and duration of regurgitant signals, 43 patients with regurgitant signals of short duration during systole or diastole were studied using M-mode color Doppler echocardiography. Using the latter method, regurgitant signals throughout systole and the isovolumic relaxation period could be demonstrated in all but four patients who had regurgitant signals of short duration during systole, but suggesting mitral or tricuspid regurgitation. In all patients with regurgitant signals of short duration during diastole, aortic or pulmonary regurgitant signals throughout diastole could be demonstrated with M-mode color Doppler echocardiography. Thus, this technique is superior to conventional pulsed Doppler echocardiography for detecting accurate timing and duration of valvular regurgitation. 3. Peak velocity of regurgitant flow: To compare the peak velocity of regurgitant flow by continuous wave Doppler and by HPRF Doppler echocardiography, 20 patients with mitral regurgitation and 22 patients with tricuspid regurgitation were examined using the both methods. In patients with severe mitral regurgitation, the peak velocity detected by HPRF Doppler echocardiography correlated well (r = 0.96) with that detected by continuous wave Doppler echocardiography. However, in patients with mild mitral regurgitation, the peak velocity detected by HPRF Doppler echocardiography was higher than that detected by continuous wave Doppler echocardiography. In patients with severe tricuspid regurgitation, the peak velocity had a close correlation (r = 0.99) with the both techniques. In patients with mild tricuspid regurgitation, the peak velocity was higher by HPRF than by continuous wave Doppler echocardiography. In conclusion, color or pulsed Doppler echocardiography should be used for detecting valvular regurgitation. M-mode color Doppler echocardiography is superior to conventional pulsed Doppler echocardiography for detecting timing and duration of valvular regurgitation.(ABSTRACT TRUNCATED AT 400 WORDS)

Echocardiography, Doppler↗

Clinical implications of pulmonary regurgitation in healthy individuals: detection by cross sectional pulsed Doppler echocardiography.

Pulsed Doppler echocardiography in healthy individuals often shows a disturbance of diastolic flow in the right ventricular outflow tract just below the pulmonary valve that suggests regurgitation. This disturbance of diastolic flow was studied in 50 healthy individuals and 40 patients with cardiopulmonary disease, some of whom had a pulmonary regurgitant murmur. Diastolic flow was disturbed in 39 of the 50 healthy individuals. In 32, cross sectional echocardiography gave a satisfactory image of the pulmonary valve. The characteristic Doppler signals usually lasted throughout diastole, were directed toward the right ventricular cavity, and gradually waned towards end diastole; they formed a spindle shaped area of abnormal signals that extended to within 10 mm of the coaptation of the pulmonary valve towards the right ventricular cavity and the pressure difference estimated from the signals by the modified Bernoulli equation seemed to be proportional to the normal retrograde transpulmonary pressure difference. In all 40 patients with cardiopulmonary disease, signals indicating pulmonary regurgitation were found whether or not a regurgitant murmur was present. When it was present, however, the spindle was longer than 20 mm and in patients with pulmonary hypertension the velocity of abnormal diastolic flow was higher than in healthy individuals. The Doppler signals registering disturbed flow in the healthy individuals resembled the signals caused by pulmonary regurgitation in the patients in terms of location, orientation, and configuration. These results show that healthy individuals usually have trivial pulmonary regurgitation. In practice the distance that the flow disturbance extends from the valve and estimated pressure difference across the valve are probably the most important variables for assessing the clinical significance of pulmonary valve regurgitation.

Adult↗

Color Doppler evaluation of valvular regurgitation in normal subjects.

To determine prospectively the prevalence of mitral, aortic, tricuspid, and pulmonary regurgitation in normal persons, 211 consecutive, apparently healthy volunteers were examined with a color Doppler flow imaging system. The subjects were divided into five age groups (group 1, 6-9 years old; group 2, 10-19 years old, group 3, 20-29 years old, group 4, 30-39 years old, and group 5, 40-49 years old). The prevalence rate of mitral regurgitation in the normal subjects was 38-45% in each group. The mitral regurgitant jets came from the posteromedial commissure in all but two subjects. No aortic regurgitant flow signals were detected in the normal subjects. Tricuspid regurgitation was detected in 15-77% in each group, and pulmonary regurgitation was detected in 28-88%. Regarding the tricuspid and pulmonic valves, the prevalence rate of regurgitation is age dependent (p less than 0.01) and tends toward the lower rate in groups over the age of 30 years. The tricuspid and pulmonary regurgitant jets came from the center of the coaptation of each valve. The area of the regurgitant jet signals in normal persons was significantly smaller (p less than 0.001) than that obtained from patients with organic valve disease. Our study shows that in a large proportion of normal persons under the age of 50 years color Doppler echocardiography permits recording of regurgitant signals behind all valves except the aortic. In conclusion, one should be aware of the existence and characteristics of regurgitation in normal persons when evaluating valvular regurgitation by Doppler techniques.

Adolescent↗

Problems in the management of elderly patients with valvular heart disease.

One hundred and nine patients over the age of 65 years with valvular heart disease have been reviewed. Of these, 57 patients were treated medically (medical group) and the remaining 52 patients underwent valve surgery (surgical group). Of the 57 patients who were treated medically, 46 (81%) were in NYHA Functional Class I or II, 7 were in Class III, and 4 were in Class IV. Among these, there were 8 deaths. The 5 year survival rate of the medical group, calculated by the actuarial method, was 90 +/- 5%. Eight patients had a nonfatal cerebrovascular accident. Of the 52 elderly patients who underwent valve surgery, 20 were in NYHA Functional Class II, 21 were in Class III, and 11 were in Class IV. Of these, there were 5 operative deaths (9.6%). Four patients died of postoperative low cardiac output syndrome and renal failure. One died of intraoperative aortic dissection. Of the 470 patients under the age of 65 years, there were 15 operative deaths (3.2%). Forty-one of the 47 hospital survivors have improved their cardiac functional classification, while 6 patients have remained in the same class as preoperatively. The average NYHA Class prior to operation was 2.7 improved to Class 1.3 after operation. The 3 year survival rate of the surgical group, calculated by the actuarial method, was 81 +/- 6%. Thus, the prognosis of asymptomatic elderly patients is good. Although operative mortality for the symptomatic elderly patients is relatively high, valve surgery can be performed with a satisfactory prognostic outlook.

Actuarial Analysis↗

[Late complications of valve replacement: the benefits of non-invasive assessment].

Non-invasive techniques were assessed for their capabilities of detecting prosthetic valve malfunctions in 70 consecutive patients with angiographically-documented or surgically-proven prosthetic valve dysfunction. Their 74 dysfunctioning valves were studied using phonocardiography, M-mode and two-dimensional echocardiography and Doppler methods, including pulsed and continuous wave (CW) Doppler echocardiography and two-dimensional Doppler color flow mapping (2DD). These results were compared among the examinations, and also compared between 43 patients with 44 dysfunctioning mechanical valves and 27 patients with 30 dysfunctioning bioprosthetic valves. Symptoms related to valve malfunction were recognized in all patients with prosthetic valve endocarditis and in all patients but one with stenotic condition. In patients with valvular regurgitation, however, symptoms were observed in only six of the 21 patients with mechanical prostheses and in 12 of the 25 patients with bioprosthetic valves (p less than 0.01). Among 43 patients with 44 mechanical valve dysfunctions, the sensitivities of phonocardiography, M-mode and two-dimensional echocardiography and Doppler techniques were 85, 65 and 86 percent, respectively, in 20 patients with stenosis; 100, 57 and 80 percent in seven patients with transvalvular regurgitation; and 100, 50 and 100 percent in 14 patients with paravalvular regurgitation. Similarly, among 27 patients with bioprosthetic valve dysfunctions, the sensitivities of phonocardiography, M-mode and two-dimensional echocardiography and Doppler methods were 67, 100 and 100 percent, respectively, in three patients with stenotic condition; 85, 65 and 100 percent in 20 patients with transvalvular regurgitation; and 60, 40 and 100 percent in five patients with paravalvular regurgitation. Furthermore, 26 of the 27 patients with malfunctioning mechanical valves and 20 of the 24 patients with malfunctioning bioprostheses had abnormal findings using more than two techniques. In addition, each patient had at least one abnormal finding. In conclusion, malfunctioning mechanical or bioprosthetic prostheses could be detected using non-invasive techniques. The combined use of phonocardiography, M-mode and two-dimensional echocardiography and Doppler techniques is most helpful in detecting malfunctioning prostheses.

Adult↗

[Antitumor effect of intermittent oral administration of UFT against human rectal cancer xenografted in nude mice].

Effect and toxicities of oral administration of UFT were examined with tumor xenografts (COK-7LiM) in nude mice. Special attention was paid to the differences between daily (Q1D X 9) and intermittent (Q4D X 3) treatments with this agent. The optimal doses of UFT were determined on the basis of the maximal tolerated dose of the agent in nude mice. It was remarkable that the chemotherapeutic effect by intermittent administration of UFT showed a significantly better result than that by daily administration. No difference was seen in the toxicities between the two methods of administration of UFT. Moreover, the concentration of 5-FU in the tumor tissue treated with UFT intermittently was significantly higher than that by daily administration method.

Administration, Oral↗

[Time analysis of mitral regurgitation in patients with mitral valve prolapse: a study by phonocardiography and Doppler techniques].

To assess the timing and duration of mitral regurgitation (MR) in patients with mitral valve prolapse (MVP), 20 subjects with mid-systolic click(s) and/or a late systolic murmur were studied using phonocardiography, two-dimensional echocardiography (2DE) and Doppler techniques including pulsed Doppler (PD), high pulse repetition frequency Doppler (HPRF), continuous wave Doppler (CW) and M-mode color Doppler (MD) methods and two-dimensional Doppler color flow mapping (2DD). The results were compared with those of 16 patients with a pansystolic murmur having late systolic accentuation. MVP with MR was observed in 15 of the 20 patients with mid-systolic clicks and/or a late systolic murmur and in all of the 16 patients with a pansystolic murmur. Using MD, MR signals were seen throughout systole and isovolumic relaxation period in all but one of these patients, and they were not related to the patterns of the systolic murmur. In only one, an MR signal was recorded just after the click. Five patients with a mid-systolic click lacked the findings of MVP, but two of them had MR signal only in early systole. Using PD and HPRF techniques, the timing and duration of MR signals in patients with mid-systolic clicks and/or a late systolic murmur were varied by changing the sites of the sample volume. Similarly, the timing and duration of MR signals in these patients were dependent on the ultrasonic beam direction by the CW method. In most patients with a pansystolic murmur having late systolic accentuation, however, MR signals throughout systole and the isovolumic relaxation period were demonstrated by each Doppler method. Therefore, PD, HPRF, and CW were not so efficiently sensitive or adequate techniques for investigating the timing and duration of MR, especially in patients with mid-systolic clicks and/or a late systolic murmur, who had mild or eccentric MR jets. In conclusion, 1) MR in MVP involves the entire systole and isovolumic relaxation period, 2) PD, HPRF and CW methods are not adequate for detecting mild or eccentric MR jets in patients with mid-systolic clicks and/or a late systolic murmur, and 3) MD is useful for the time analysis of MR in these patients.

Adolescent↗

[Ventricular free wall rupture following acute myocardial infarction: a two-dimensional echocardiographic assessment].

To assess the usefulness of two-dimensional echocardiography (2DE) in diagnosing ventricular free wall rupture following acute myocardial infarction, we studied the 2DE findings and the clinical pictures of seven consecutive patients with ventricular free wall rupture confirmed at the time of surgery or autopsy. Three patients had acute rupture; four, subacute rupture. All patients apparently had circulatory collapse despite continuing electrical activity at the onset of cardiac rupture. Four patients with subacute rupture recovered. In all patients, mild pericardial effusion was imaged by 2DE; however, this was not characteristic for cardiac rupture. In the patients with acute rupture, active left ventricular contractions were not observed after each QRS complex of the electrocardiogram. However, weak mitral valve motion was recorded at the time of cardiopulmonary resuscitation. The interesting and constant finding in acute rupture was the right ventricular collapse observed throughout the cardiac cycle. Diastolic right ventricular collapse was consistently observed in patients with subacute rupture, immediately after recovery from cardiogenic shock. Subacute cardiac rupture is a potentially curable lesion, and the clinical features and quick 2DE confirmation of cardiac tamponade allowed immediate surgery which saved two of the four patients.

Adult↗

[Color Doppler evaluation of a specific left ventricular flow pattern in a case of left ventricular pseudoaneurysm].

This report describes a case of left ventricular pseudoaneurysm examined by phonocardiography, two-dimensional echocardiography, Doppler color flow mapping, continuous wave and conventional pulsed Doppler echocardiography. The patient had early systolic and early diastolic murmurs. The pseudoaneurysm sac and the site of left ventricular rupture were identified by two-dimensional echocardiography. The flow between the left ventricle and the pseudoaneurysm were imaged by Doppler color flow mapping. Two jets from the left ventricle were directed toward the aneurysm during systole, and from the aneurysm toward the left ventricle in early diastole. Continuous wave Doppler and high pulse repetition frequency Doppler echocardiography demonstrated the maximum flow velocity in systole to be 3 m/sec and in early diastole, 1.7 m/sec. Those flow patterns between the left ventricle and the pseudoaneurysm could have been closely related to the murmur. Doppler echocardiography thus proved useful for detecting specific flow patterns related to a left ventricular pseudoaneurysm.

Aged↗

Enzymological characteristics of avian influenza A virus neuraminidase.

Neuraminidases of 18 strains of avian influenza A virus were examined by both colorimetric and fluorometric assays using fetuin and 4-methylumbelliferyl-N-Ac-alpha-D-neuraminide as substrates, respectively, to compare them with those of human influenza A and B viruses. The ratios of the neuraminidase activity of avian influenza virus measured by the colorimetric assay method to that measured by the fluorometric assay were distributed in the range of 2.4-20.3. The enzyme of avian influenza virus showed calcium-ion dependence in both assay methods. These results suggest that neuraminidase of avian influenza A virus is varies greatly from one strain to another in substrate specificity as compared with those of human influenza A and B viruses, and that some strains of avian influenza A virus have a neuraminidase with unique enzymological characteristics different from that of human influenza A virus as well as that of influenza B virus.

Colorimetry↗

Age-related valvular regurgitation: a study by pulsed Doppler echocardiography.

To assess the prevalence of valvular regurgitation in the aged, we studied 176 apparently healthy volunteers with no history or physical evidence of cardiac abnormality. Their ages ranged from 40 to 90 (66 +/- 14, mean +/- SD) years. We examined these subjects by pulsed Doppler echocardiography combined with two-dimensional echocardiography to determine the prevalence of valvular regurgitation. Regurgitation began to appear in subjects in their fifties, increasing in prevalence with advancing age (r = .81, p less than .001), and was documented in all over age 80. Similarly, regurgitation involving more than one valve appeared in those 60 years and older, and was very common (89%) in subjects in their eighties. With each type of valvular regurgitation, the prevalence of each type of regurgitation increased with aging, but this tendency was most prominent for aortic regurgitation. We conclude that (1) single or multivalvular regurgitation as detected by pulsed Doppler echocardiography is very common in the aged and may be considered a normal finding in the absence of other evidence of heart disease, and (2) the high prevalence of regurgitation in the aged must be taken into account when Doppler examinations are being performed.

Adult↗

[Mechanical and electrocardiographic sequence of coronary artery occlusion: an echocardiographic study during coronary angioplasty].

The detection of regional myocardial dysfunction due to acute ischemic event has been limited almost entirely to experimental animal models. In human subjects, it has been limited to the observations during spontaneously-occurring or exercise-induced ischemic events. Recently, percutaneous transluminal coronary angioplasty (PTCA) provides an opportunity to study such dysfunction as the result of repeated interruptions of coronary blood flow. Echocardiograms and electrocardiograms were simultaneously recorded immediately before, during, and after 21 episodes of complete interruptions of coronary blood flow by PTCA in 11 patients. No patient had asynergy of the left ventricle either by two-dimensional echocardiography (2DE) or angiography. All patients had isolated single coronary artery stenosis including the left anterior descending artery in nine, left circumflex artery in one and right coronary artery in one. Recordings of M-mode and 2DE were successfully obtained in 10 patients. After balloon inflation, regional asynergy in the distribution of the instrumented coronary artery appeared in all 10 patients. Hypokinesis developed 9 +/- 3 (means +/- SD) sec after balloon inflation and progressed rapidly to akinesis or dyskinesis. At the same time, decreased systolic thickening of the left ventricular wall appeared in some patients in relation to the development of regional asynergy. However, systolic thinning of the left ventricular wall was not noted in all. The regional asynergy preceded ischemic electrocardiographic changes and had no relation to chest pain. Left ventricular wall motion began to normalize 12 +/- 3 sec after balloon deflation. Thereafter, transient hyperkinesis of the left ventricle developed. The first ischemic electrocardiographic change was a negative U wave which appeared 13 +/- 7 sec after coronary occlusion and remained 3 to 4 sec. Tall T waves were recorded at 28 +/- 12 sec and significant ST elevations developed 31 +/- 11 sec, after balloon inflation. These electrocardiographic changes invariably occurred only after the onset of wall motion abnormalities. Normalization of T waves was recognized at 17 +/- 16 sec and ST segment deviation were no longer present at 18 +/- 10 sec, after reperfusion. These electrocardiographic changes also preceded normalization of regional myocardial dysfunction. In conclusion, left ventricular wall motion abnormalities after coronary occlusion invariably precede the electrocardiographic changes, and begin to normalize after reperfusion prior to the electrocardiographic recovery.

Adult↗