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T Tabata

Publications and source records attributed to T Tabata.

At least 127 records · Page 7Linked to original sources
PubMed1997

[Clinical study of gasless laparoscopic adrenalectomy in 17 cases--comparison between laparoscopic adrenalectomy with and without pneumoperitoneum].

PURPOSE: To determine the efficiency of gasless laparoscopic adrenalectomy, this procedure was compared to that with pneumoperitoneum. PATIENTS AND METHODS: Between February 1994 and December 1996, 17 gasless laparoscopic adrenalectomy were performed in 5 men and 12 women, 36 to 79 years old. Clinical diagnosis was primary aldosteronism in 8, pheocromocytoma in 2, incidentaloma in 4 and adrenal cyst in 3. When gasless laparoscopic adrenalectomy was performed, the laparoscope was inserted through the upper margin of the umbilicus by open laparotomy. To create a workable space, a 1.2 mm Kirschner wire was advanced subcutaneously below the costal arch and attached to a retractor. Operating time, estimated blood loss, changes of the end tidal CO2 concentration during operation, operative complications and postoperative course were compared to those with pneumoperitoneum in 12 cases. RESULTS: In both procedures, satisfying workable spaces were created in all cases. The mean operating time and estimated blood loss were 245 min and 201 ml without pneumoperitoneum, 317 min and 274 ml with pneumoperitoneum, respectively. The mean changes of end tidal CO2 concentration during operation were 3.2 mmHg without pneumoperitoneum and 5.1 mmHg with pneumoperitoneum. As operative complications, open operations were required in 2 cases (1 without pneumoperitoneum and another with pneumoperitoneum) to control intraoperative bleeding. They had the histories of transabdominal operations. Postoperative bleeding was observed in 2 cases (1 without pneumoperitoneum and another with pneumoperitoneum). One of them (with pneumoperitoneum) needed surgical management for hemostasis. Fever over 38 degrees C that occurred in 1 case with pneumoperitoneum appeared to be absorption fever. No differences were observed in the number of the days to the start of oral intake and for postoperative hospitalization between the two groups. CONCLUSIONS: Gasless laparoscopic adrenalectomy is available for most adrenal tumors. Suction could be used unrestrictedly and there were no hemodynamic or ventilatory effects due to pneumoperitoneum. This procedure appears to be safe and advantageous for the treatment of most adrenal tumors.

Adrenal Gland Diseases↗
PubMed1997

[A case of systemic origin of an aberrant artery to the basal segment of the lung].

We report on a rare case of systemic origin of an aberrant artery to the basal segment of the lung (Pryce I type intralobar pulmonary sequestration) that caused occasional bloody sputum. The patient was admitted to our hospital after an abnormal image was discovered in Chest X-ray film. The chest MRI showed an abnormal vessel originating from the descending aorta. The aortagram showed an abnormal artery originating from the descending aorta and entering the left lower lobe, and the left pulmonary angiogram revealed a poorly blood supply to the left basal segments. The preoperative diagnosis of systemic origin of an aberrant artery to the basal segment of the lung was given. The patient was subjected to surgical treatment. During surgery, it was found that the abnormal artery, 12 mm in diameter, which was connected from the descending aorta to the left basal segments. The abnormal artery was dissected, and the left basal segments was removed. The postoperative course was uneventful.

Aorta, Thoracic↗
PubMed1997

[Role of leukotriene B4 in monocrotaline-induced pulmonary hypertension].

Monocrotaline (MCT) causes lung inflammation and chronic pulmonary hypertension associated with lung vascular thickening in rats. We hypothesized that leukotriene B4 (LTB4) and LTB4-induced accumulation of leukocytes in the lung play a role in MCT-induced lung disease, and therefore measured LTB4 and myeloperoxidase (MPO) levels in lung tissue of MCT-treated rats. Next, we examined the effect of an orally active LTB4 receptor antagonist (ONO4057) on MPO levels in lung tissue, on pulmonary hypertension, and on pulmonary vascular remodeling induced by MCT. Lung LTB4 and MPO levels had increased by 3 days after MCT injection. In the ONO4057-treated MCT rats, lung MPO levels were significantly lower than in the rats given MCT but not ONO4057. By the third week after injection. MCT had caused increases in mean pulmonary arterial pressure, in the ratio of right ventricular weight to left ventricle+septum weight (RV/[VS + S]), and in media wall thickness of the muscular arteries of the lung. Treatment with ONO4057, either for 3 weeks or during the first week after MCT injection, significantly reduced pulmonary hypertension, right ventricular hypertrophy, and lung vascular thickening induced by MCT. These results indicate that ONO4057 reduces both the accumulation of leukocytes in lung tissue and the chronic pulmonary hypertension induced by MCT, and they suggest a role for LTB4 in the inflammatory process that contributes to pulmonary hypertension and lung vascular remodeling induced by MCT in rats.

Animals↗
PubMed1997

Tricuspid inflow and regurgitant flow dynamics after mitral valve replacement: differences relating to surgical repair of the tricuspid valve.

BACKGROUND AND AIMS OF THE STUDY: Changes in tricuspid inflow and regurgitant flow dynamics were evaluated in patients with functional tricuspid regurgitation (TR) who underwent mitral valve replacement (MVR) with and without tricuspid annuloplasty (TAP). METHODS: In a group of 30 patients, all with atrial fibrillation, 15 underwent TAP performed according to the modified De Vega technique; the remaining 15 did not undergo TAP. Patients were studied before and serially after surgery, using pulsed and color Doppler echocardiography. The mean follow up was 4.7 years in the TAP group and 5.1 years in the non-TAP group. RESULTS: In the TAP group, immediately after surgery, the area of the TR jet decreased markedly, and the deceleration time of the tricuspid inflow velocity wave was significantly prolonged compared with that before surgery. By contrast, in the non-TAP group, both the area of the TR jet and deceleration time of tricuspid inflow velocity were virtually unchanged. The area of the TR jet remained small for a long period in the TAP group, but in non-TAP patients was increased in four cases over seven years, with two patients developing right-sided heart failure. Recent data showed the area of the TR jet to be significantly smaller, with maximum tricuspid inflow velocity significantly increased, and deceleration time of the tricuspid inflow velocity wave significantly prolonged in the TAP group compared with the non-TAP group. CONCLUSIONS: In patients with functional tricuspid regurgitation undergoing MVR, concomitant TAP may cause mild tricuspid stenosis, but produces sustained preventive effects against TR. Careful follow up is needed in patients who have not undergone TAP, as TR is not markedly decreased and may even be exacerbated. Aggressive TAP is recommended in patients showing dilatation of the tricuspid annulus, even if TR is mild.

Adult↗
PubMed1997

The 'sail sound' and tricuspid regurgitation in Ebstein's anomaly: the value of echocardiography in evaluating their mechanisms.

We describe a patient with Ebstein's anomaly in whom Doppler echocardiography was used to clarify the mechanism responsible for 'sail sound' and tricuspid regurgitation associated with this condition. Phonocardiography revealed an additional early systolic heart sound, consisting of a first low-amplitude component (T1) and a second high-amplitude component (T2, 'sail sound'). In simultaneous recordings of the tricuspid valve motion using M mode echocardiography and phonocardiography, the closing of the tricuspid valve occurred with T1 which originated at the tip of the tricuspid leaflets, while T2 originated from the body of the tricuspid leaflets. Using color Doppler imaging, the tricuspid regurgitant signal was detected during pansystole, indicating a blue signal during the phase corresponding to T1 and a mosaic signal during the phase corresponding to T2 at end-systole. Thus, 'sail sound' in patients with Ebstein's anomaly is not simply a closing sound of the tricuspid valve, but a complex closing sound which includes a sudden stopping sound after the anterior and/or other tricuspid leaflets balloon out at systole.

Diagnosis, Differential↗
PubMed1997

[Effect of thoracoscopic procedure versus standard posterolateral/muscle-sparing thoracotomy on pulmonary lung function].

To understand the effects of thoracoscopic approach to thoracotomy on lung function, we investigated the changes in lung function after thoracoscopic operation (n = 7) and compared them to those after standard posterolateral (n = 5) or muscle-sparing thoracotomy (n = 6). In 18 patients with benign lung tumor in which surgical treatment resected in partial resection of the lung tissue, we measured TLC, VC, RV, FEV1.0, FEV1.0%, Peak Flow and DLco preoperatively and at 2, 4 weeks postoperatively. In the standard posterolateral or muscle-sparing thoracotomy groups, FVC, TLC, FEV1.0 and Peak Flow decreased to about 80% of preoperative value at 2 weeks. At 4 weeks after operation, these values showed to increase some what, but did not reach to the preoperative value. Whereas, the thoracoscopic procedure group, did not show the decrease in lung function through the time course. There was not significant different between standard posterolateral and muscle-sparing thoracotomy. We conclude that thoracoscopic approach is an useful technique to thoracotomy because of its minimizing after thoracotomy effect of lung function loss.

Adult↗
PubMed1997

[Increase in pulmonary vascular permeability caused by increased expression of Mac-1 on the surface of polymorphonuclear leukocytes].

We studied the expression of adhesion molecules on the surface of human polymorphonuclear leukocytes (PMNs). The effects of mechanical stimulation were measured with a flow cytometer and pulmonary vascular injury due to accumulation of PMNs in the lungs was assessed by a gravimetric method. The accumulation of PMNs in the lungs was studied by measuring the amount of myeloperoxidase. PMNs were stimulated by gentle agitation in a glass container for 10 s. Mac-1 (CD11b/CD18) was upregulated on the surface of PMNs that were mechanically stimulated. When unstimulated PMNs were exposed to isolated rat lungs, the filtration coefficient did not change from that under baseline conditions. However, when mechanically stimulated PMNs were exposed to isolated rat lungs, the filtration coefficient was about 5 times higher than that measured at baseline. When mechanically stimulated PMNs treated with anti-CD18 antibody were used, the increase in the filtration coefficient was completely blocked. The assay of myeloperoxidase revealed that PMNs stuck to isolated rat lungs only after stimulated PMNs were added. We conclude that when the adhesiveness of PMNs is increased by mechanical stimulation, these cells adhere to pulmonary vessels and increase pulmonary vascular permeability.

Animals↗
PubMed1997

[Prediction of postoperative pulmonary hemodynamics for the second lobectomy after the contralateral lobectomy].

We presented 7 cases who were performed the second lobectomy for the second lung cancer after the first successful lobectomy on the contralateral lung (3 cases for right upper lobectomy + left lower lobectomy and 4 cases for right upper lobectomy + left lower lobectomy). In 6 patients, the predicted postoperative FEV1 estimated by multiplying the preoperative FEV1 by the fraction of perfusion to the contralateral lung was less than 800 ml/m2BSA, which is our first cut-off for identifying lung resection candidates. Unilateral pulmonary arterial occlusion test (UPAO) revealed that total pulmonary vascular resistance (TPVRI) in 3 of those 6 patients was lower than 700 dyne.sec.cm-5/m2BSA, our second cut-off for lung resection. More precise postlobectomy pulmonary hemodynamics in another 3 of those 6 patients were then estimated by adapting selective pulmonary occlusion test (SPAO). Since TPVRI during SPAO was lower than the cut-off value, it was suggested that second lobectomy would be feasible with low incidence of post operative cardiopulmonary complication. There was no serious complications in all 7 cases during their postoperative course. We believe that more precise prediction of postoperative pulmonary hemodynamics by adapting UPAO and SPAO could be one of the tools to minimumize postoperative cardiopulmonary complications in those patients needed second lobectomy for the second lung cancer after the first successful lobectomy on the contralateral lung even though their impaired lung fung function.

Aged↗
PubMed1996

Hepatitis C biochemical remission and viral replication in haemodialysis patients.

The natural course of non-A, non-B (type C) hepatitis was studied in 62 haemodialysis patients. From the onset of the disease, serum alanine aminotransferase levels were monitored monthly for 9-218 mon (median 115). After fluctuation of aminotransferase levels for 1-206 mon (median 39), 57 (92%) patients showed normalization of these levels lasting until the end of the follow-up, which was for > 2 yr in 31 (50%) cases and for > 5 yr in 15 (24%) cases. At the end of follow-up, hepatitis C viraemia was assessed by reverse transcription-polymerase chain reaction (RT-PCR) and branched DNA (bDNA) assay. Viraemic levels were significantly lower in the 15 patients with normal aminotransferase for > 5 yr (median RT-PCR + ve/bDNA-ve, range RT-PCR-ve to 10(6.7) Eq/mL) than in the 47 cases with normal levels for < 5 yr (median 10(6.6), range RT-PCR + ve/bDNA-ve to 10(7.6) Eq/mL) (P < 0.01). Moreover, a significant inverse relation was observed between viraemic levels and the duration of aminotransferase normalization (r = -0.46, P < 0.01). These findings indicate that biochemical remission of hepatitis C may be frequent in haemodialysis patients and may be related to viral attenuation.

Adult↗
PubMed1996

Changes in left ventricular inflow and pulmonary venous flow velocities during preload alteration in dilated heart.

The aim of the present study was to assess the changes of left ventricular inflow (LVIF) and pulmonary venous flow (PVF) velocities during preload alteration in 30 patients with dilated heart (LV end-diastolic dimension > or = 6.0 cm) and impaired LV systolic function (% fractional shortening of the LV < or = 25%). We performed transesophageal pulsed Doppler echocardiography during lower body negative (LBNP, -40 mmHg) and positive pressure (LBPP, +40 mmHg) in 10 patients with dilated cardiomyopathy, in 20 with old myocardial infarction, and in 22 healthy controls. Eight of the patients showed a pseudonormalization (compliance failure) pattern, and 22 showed a decreased early diastolic wave and compensatorily increased atrial systolic wave (relaxation failure) pattern of LVIF in the control state. Mean pulmonary capillary wedge pressure (PCWP) was greater in the compliance failure group than in the relaxation failure group in the control state. LVIF in 6 of the 22 patients with the relaxation failure pattern changed to the compliance failure pattern during LBPP, and that in 3 of 8 patients in the compliance failure group changed to the relaxation failure pattern during LBNP. The 6 patients with a change from the relaxation failure to the compliance failure pattern showed significantly higher peak diastolic and atrial systolic PVFs during LBPP than in the control state, and significantly higher PCWPs in the control state than the 16 patients with no change in LVIF. These findings suggest that the compliance failure and relaxation failure patterns of LVIF are readily interchangeable in various hemodynamic conditions, and that pattern analysis of LVIF and PVF during preload alteration is useful for understanding the hemodynamic severity and for evaluating preload reduction therapy in the dilated heart.

Blood Flow Velocity↗
PubMed1996

Clinical significance of the apical late systolic ejection murmur: a new phonocardiographic sign indicating dynamic mid-left ventricular obstruction.

Systolic ejection murmurs of the left heart usually have their peak during early to mid-systole. Few reports have addressed ejection murmurs with their peak at late systole. We evaluated the clinical significance of an apical systolic ejection murmur with a peak intensity during late systole using Doppler and two-dimensional (2-D) echocardiography and phonocardiography. The apical late systolic ejection murmur was observed in 9 of 13 consecutive patients with mid-left ventricular obstruction. We investigated the ejection flow velocity and the timing of maximum velocity at the three different sites of the left ventricle, the left ventricular cavity shape, and the timing of the peak murmur intensity in these nine patients (late-murmur group). The same parameters were also examined in 8 consecutive patients with mid-systolic ejection murmurs (mid-murmur group), 10 with early systolic ejection murmurs (early-murmur group), and 7 controls without murmurs. Patients with aortic stenosis were excluded. The mid-ventricular ejection flow velocity was significantly higher in the late-murmur group than in the other three groups; that of the outflow tract was markedly higher in the mid-murmur group. The ejection flow velocity at the aortic orifice of patients in the early-murmur group was significantly high compared with that of the controls. The timing of the peak murmur intensity in each group correlated with that of the peak flow signal at the corresponding site with maximum velocity. In all patients in the late-murmur group, 2-D echocardiography revealed a systolic narrowing of the cavity at the mid-ventricle. Amyl nitrite inhalation induced a marked increase in the intensity of the murmur without evidence of appearing or increasing mitral regurgitation. It was concluded that the apical ejection murmur with a late systolic peak intensity is a new phonocardiographic sign indicative of dynamic, mid-left ventricular obstruction. This murmur should be differentiated from the mitral regurgitant murmur.

Adult↗
PubMed1996

Possible mechanisms of mitral regurgitation in dilated hearts: a study using transesophageal echocardiography.

HYPOTHESIS: This study was undertaken to clarify the mechanisms of mitral regurgitation (MR) in dilated hearts. METHODS: In all, 68 patients with dilated heart and MR, including 26 patients with dilated cardiomyopathy (DCM), 24 with prior anterior myocardial infarction (A-MI), and 18 with prior posteroinferior myocardial infarction (I-MI), as well as 25 normal subjects were examined by transesophageal two-dimensional and color Doppler echocardiography. RESULTS: The maximum area of the MR signal in the DCM group correlated positively with the anteroposterior diameter of the mitral annulus at late systole. Although the coaptation edge length of the anterior and posterior mitral leaflets appeared shorter in dilated hearts than in the hearts of controls, a significant difference did not exist. The length of the coaptation edge correlated negatively with the maximum area of the MR signal in all dilated hearts, and characteristic systolic displacement of the coaptation point of both mitral leaflets occurred. The MI groups demonstrated anterior and posterior displacement in the direction of the short axis of the left ventricle in the A-MI and I-MI groups, respectively. However, the DCM group demonstrated inferior displacement toward the long axis of the left ventricle; its magnitude correlated positively with the maximum area of the MR signal. CONCLUSION: A major cause of MR in dilated hearts is mitral malcoaptation due to displacement of the coaptation point of the mitral leaflets along the long or short axis of the left ventricle. This is caused by left ventricular enlargement and/or asynergy of the left ventricular wall, rather than by a decrease in mitral coaptation edge length due to mitral annular dilation.

Adult↗
PubMed1996

Omega-conotoxin-MVIID blocks an omega-conotoxin-GVIA-sensitive, high-threshold Ca2+ current in fish retinal ganglion cells.

Reduction of Ca2+ current amplitude by the Conus peptide omega-conotoxin-MVIID (omega-CTx-MVIID) was measured in voltage-clamped, goldfish retinal ganglion cells. Effects of depolarizing shifts in holding potential, and sequential applications of omega-CTx-MVIID, omega-CTx-GVIA, and BAY-K-8644, together with effects of Ni2+ and omega-Aga-IIIA, indicated that omega-CTx-MVIID may target Ca2+ channels differing from those termed T, L, N, P < Q and R.

Animals↗
PubMed1996

Changes in transmitral and pulmonary venous flow velocity patterns after cardioversion of atrial fibrillation.

To examine the recovery time of left atrial mechanical function after electrical cardioversion of atrial fibrillation, we recorded transmitral flow, pulmonary venous flow velocities, and interatrial septal motion during atrial systole within 24 hours (16 +/- 5 hours) and 10 days after cardioversion in 25 patients with atrial fibrillation, including 6 patients with hypertension, 4 with ischemic heart disease, 2 with alcoholic heart disease, 5 with dilated cardiomyopathy, and 8 with no evidence of underlying heart disease. With the exception of the five patients with dilated cardiomyopathy, the peak atrial systolic transmitral and pulmonary venous flow velocities, peak first systolic velocity of pulmonary venous flow, duration of both atrial systolic waves, and amplitude of the interatrial septal motion during atrial systole decreased markedly within 24 hours after cardioversion and increased 10 days after cardioversion. These results suggest that active atrial systolic and relaxant variables obtained from transmitral and pulmonary venous flow velocities may reflect left atrial mechanical function after cardioversion of atrial fibrillation.

Atrial Fibrillation↗
PubMed1996

Relationship between pulmonary capillary wedge V wave and transmitral and pulmonary venous flow velocity patterns in various heart diseases.

BACKGROUND: A large V wave in a pulmonary capillary wedge pressure (PCWP) tracing is characteristic of mitral regurgitation. However, the V wave is often increased in patients without or with no significant mitral regurgitation. METHODS AND RESULTS: The V wave was in the PCWP tracing investigated in 65 patients using transmitral flow (TMF) and pulmonary venous flow (PVF) velocity patterns obtained by transesophageal pulsed Doppler echocardiography. A large V wave was defined if the peak V wave minus the mean PCWP (V-mPCWP) was greater than 7 mmHg. Three study groups were formed: 15 patients with large V waves and significant mitral regurgitation, 15 patients with large V waves with no significant mitral regurgitation, and 35 patients with small V waves. The mPCWP and left ventricular end-diastolic pressure were greatest in the group with large V waves and no significant mitral regurgitation. Peak early diastolic TMF and PVF velocities were significantly greater in the two groups with large V waves. The peak second systolic PVF velocity was lowest in the group with large V waves and significant mitral regurgitation, followed by the group with large V waves and no significant mitral regurgitation. The V-mPCWP was positively correlated with the peak early diastolic TMF and PVF velocities and negatively correlated with the peak second systolic PVF velocities. Additionally, mitral regurgitation severity in patients with large V waves and significant mitral regurgitation was positively correlated with the peak early diastolic TMF and PVF velocities and negatively correlated with the peak second systolic PVF velocity. CONCLUSIONS: These results suggest that large V waves in PCWP tracings appear not only in severe mitral regurgitation, but also in any condition with markedly elevated left ventricular end-diastolic pressure. Combined analysis of the TMF and PVF velocity patterns is helpful in determining the etiology of these hemodynamic abnormalities.

Blood Flow Velocity↗