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Biomedical subjects

T Misaki

Publications and source records attributed to T Misaki.

At least 145 records · Page 8Linked to original sources

Surgical treatment of patients with Wolff-Parkinson-White syndrome and associated acquired valvular heart disease.

Between November 1973 and March 1993, 454 patients underwent surgical division of an accessory pathway. The surgical and electrophysiologic data for 15 of these patients who underwent concomitant operation for acquired valvular heart disease were examined. This subgroup consisted of 10 male and 5 female patients whose ages ranged from 11 to 62 years (mean 51.6 +/- 9.7 years). The primary surgical indication was congestive heart failure in all cases; a concomitant history of cardiopulmonary resuscitation was present in two cases. Nine of these patients had mitral valve disease, three had aortic valve disease, two had combined aortic and mitral valve disease, and one had tricuspid valve disease. The surgical technique used for the treatment of Wolff-Parkinson-White syndrome included (1) an endocardial approach with the use of cardioplegic arrest, (2) a sharp dissection of the involved valve anulus, and (3) cryoablation. Concomitant surgical treatments of valvular heart disease included open mitral commissurotomy in five cases, mitral valve replacement in four cases, aortic valve replacement in three cases, aortic valve replacement with mitral valve commissurotomy in two cases, and tricuspid valvuloplasty (De Vega technique) in one case. Other concomitant surgical procedures included tricuspid annuloplasty with atrialized right ventricle and replacement of the ascending aorta in one case and left ventricular myectomy for hypertrophic obstructive cardiomyopathy in one case. No early deaths occurred. A successful disappearance of the delta wave and episodes of recurrent tachycardia were achieved in all 15 patients. Long-term surgical follow-up, averaging 86.2 +/- 54.8 months also demonstrated no late instances or recurrence of either a delta wave or tachycardia.

Adolescent↗

[A case report of scimitar syndrome: a new technique in the correction of partial anomalous pulmonary venous drainage].

A twenty eight year-old man with anomalous pulmonary venous drainage from the right lung to the inferior vena cava (scimitar syndrome) underwent surgical treatment. We have successfully modified the surgical technique that consists of using the anterior wall of the right atrium, to form a tunnel that will divert the anomalous pulmonary vein to the left atrium. After rerouting of the anomalous pulmonary vein, the anterior wall of the right atrium was reconstructed with a polytetrafluoroethylene patch. To our knowledge, this is the first time this technique has been used to correct this syndrome.

Adult↗

[Basic and clinical evaluation of a novel immunoradiometric assay kit for free thyroxine].

We have evaluated a new immunoradiometric assay for free thyroxine (T4) utilizing thyroxine-coated particles and radioiodinated monoclonal anti-T4 antibodies. The assay results were reproducible with coefficients of variation no more than 3.1% for intraassay and no more than 6.7% for interassay. Serum free T4 values for 48 healthy subjects distributed at 1.13 +/- 0.19 ng/dl (mean +/- SD). In various thyroid diseases, the results with the new kit compared well with two other measurements (T4-analog RIA and equilibrium dialysis RIA). Altered concentration of thyroxine binding globulin did not significantly affect this assay, while anti-thyroxine autoantibodies caused factitiously elevated free T4 values in some cases. In pregnancy, free T4 concentration tended to decline mildly in late stages. About 20% of hypoalbuminemic samples from patients with nonthyroidal illnesses had free T4 concentration more than 2.00 ng/dl, probably due to renal failure or to the use of diuretics, heparin, or other drugs which may increase serum free T4 fraction in vivo. In conclusion, this new free T4 IRMA kit is convenient and reproducible, and suitable for routine measurement of clinical material.

Animals↗

Radioiodine uptake by squamous-cell carcinoma of the lung.

A patient with a history of total thyroidectomy for papillary carcinoma showed a solitary hot spot in the chest on post-therapy radioiodine imaging. Subsequent evaluation demonstrated that this lesion was a primary squamous-cell lung cancer. Our case illustrates a rare but important differential diagnosis from lung metastasis of thyroid cancer in 131I scintigraphy. Alternatively, this "aberrant uptake" might be a rather common phenomenon for lung neoplasms, although the underlying mechanism is not yet known. Future experimental studies might lead to a new application of radioiodine imaging in pulmonary oncology.

Adenocarcinoma, Papillary↗

Scintigraphic findings of the thyroid in euthyroid ophthalmic Graves' disease.

UNLABELLED: The scintigraphic findings of the thyroid were analyzed in patients with euthyroid ophthalmic Graves' disease known to have some thyroid-related abnormalities. METHODS: Technetium-99m-pertechnetate images of the thyroid from 38 euthyroid ophthalmic Graves' disease patients with small, soft or nonpalpable goiter were analyzed. RESULTS: Scan images showed homogeneous (even) and nonhomogeneous (uneven) 99mTc uptake in 20 and 16 patients respectively. Poor images due to low uptake were observed in two patients. Six patients displayed alterations in scintigraphic appearance from even to uneven patterns after T3 suppression test. Statistical analysis revealed that the uneven pattern was more frequently observed in euthyroid ophthalmic Graves' disease patients than in 26 patients with hyperthyroid Graves' disease who were euthyroid during antithyroid drug therapy (p < 0.005). The scintigraphic heterogeneity was correlated with reduced uptake as well as a higher ratio of the uptake values after T3 treatment to the pretreatment values. Scintigraphically, hot or warm lesions were observed in most cases showing the uneven pattern (16/22; 73%). Rather low titers of antithyroglobulin, antimicrosomal antibodies and TSH-binding inhibitor immunoglobulins were detected in only 4 (10.5%), 7 (18.4%) and 12 (31.6%) patients respectively, while the prevalence of thyroid-stimulating antibodies (TSAb) was as high as 86.8% (33/38). The scintigraphic heterogeneity did not correlate with the detection of these antibodies but did correlated with the severity and duration of ophthalmopathy. CONCLUSIONS: The presence of functioning follicular cells with some autonomy that were heterogeneously distributed in the thyroid was observed in about half the euthyroid ophthalmic Graves' disease patients. Chronic stimulation by TSAb may be the underlying mechanism for these findings.

Adolescent↗

[Use of inferior epigastric artery for coronary artery bypass grafting].

Between 3/91 and 3/93 twenty-nine patients (pts.) with a mean age of 55 years (30-68) underwent CABG (including 3 reoperation) using inferior epigastric artery (IEA) in addition to internal thoracic artery and saphenous vein graft. IEAs were harvested as pedicles with a mean length of 12.2 cm (7.5-17). Overall distal anastomoses were performed 3.2 per patients. And a mean of 2.3 anastomoses were completed as an arterial graft. IEA grafts were applied to left anterior descending artery in 10, diagonal branch in 15, in marginal branches in 2 and right coronary artery in 2. Mean cardiopulmonary bypass time amounted to 103 minutes and operation procedures were completed in 258 minutes (mean). Aortic cross clamp time of 48 minutes were required. One patient was died of cerebral accident 23 days postoperatively. Except for two abdominal wall infection no wound healing problems occurred. One reexploration for bleeding were necessary. Postoperative angiography revealed patent IEA grafts in 12 of 13 patients (92%). We concluded that the application of IEAs for CABG is available as a third arterial graft and with respect to intraoperative management and perioperative complications use of IEA combined with ITAs appears suited or superior to the use of the right gastroepiploic artery.

Abdominal Muscles↗

Increased uptake of iodine-131 in metastases of differentiated thyroid carcinoma associated with less severe hypothyroidism following total thyroidectomy.

BACKGROUND: In an attempt to determine possible factors affecting the efficacy of iodine-131 (I-131) treatment for metastatic thyroid carcinoma, the authors focused their efforts on thyroid functions after total thyroidectomy. METHODS: Between 1980 and 1991, 47 patients with lung metastases of differentiated thyroid carcinoma were treated with I-131. Relationships of the images on post-therapy scans with various clinical features were studied. RESULTS: Among them, 28 (59.6%) showed I-131 uptake in the metastases on post-therapy scans. Younger patients had lesions that concentrated more radioactive iodine than did those of older patients. The amount of I-131 concentrated in the metastatic lesions correlated with serum triiodothyronine (T3), thyroxine (T4), and thyroglobulin levels and inversely with serum thyroid-stimulating hormone (TSH) levels determined at the time of therapy. Serum T3 and T4 levels were significantly higher in 28 patients with positive scans than in 19 patients with negative scans. Most patients who had metastases with markedly increased radioactivity were euthyroid or mildly hypothyroid, suggesting that thyroid hormones produced by tumor masses compensated for severe hypothyroidism after total thyroidectomy, and showed favorable responses to the treatment. In three patients successfully treated, decreases in serum thyroglobulin levels and the size of metastatic lesions were accompanied by the development of severe hypothyroidism. CONCLUSIONS: The presence of a large amount of metastatic functioning thyroid tissues responsive to I-131 treatment can be suspected in patients with less severe hypothyroidism after total thyroidectomy.

Adenocarcinoma↗

Composite reconstruction of the esophagus.

Composite reconstruction of the esophagus using both the mobilized stomach and free jejunal graft is described. Tension at the anastomotic site can be minimized with interposition of a jejunal autograft between the pharyngeal stump and the mobilized stomach, even when the mobilized stomach is not long enough. Furthermore, problems derived from differing calibers of the pharyngeal stump and the mobilized stomach can be resolved by creating an end-to-side pharyngojejunal anastomosis. Our method is proposed as one procedure for reconstruction of the esophagus when the pull-up organ is too short.

Anastomosis, Surgical↗

Effect of low-dose aprotinin on coagulation and fibrinolysis in cardiopulmonary bypass.

To study the effect of low-dose aprotinin on hemostasis in patients undergoing cardiopulmonary bypass (CPB) for coronary artery bypass operations and to elucidate the mechanism of aprotinin action, we randomized 14 of 27 patients to receive 30,000 KIU/kg aprotinin in the CPB priming volume and 7,500 KIU/kg aprotinin intravenously each hour during CPB (1 patient was excluded from the aprotinin group because of protamine shock). Intraoperative and postoperative blood loss was significantly reduced in the aprotinin group. Antithrombin III level was significantly decreased, and the levels of thrombin-antithrombin III complexes were significantly increased during CPB in both groups, indicating activation of the clotting system. The marked increase in fibrin(ogen) degradation products during CPB in the control group, indicating enhanced fibrinolytic activity, was significantly reduced in the aprotinin group. alpha 2-Plasmin inhibitor was significantly reduced during CPB in the control group. The marked increase in alpha 2-plasmin inhibitor-plasmin complexes in the control group, indicating plasmin activity, was significantly reduced in the aprotinin group. A marked decrease in the platelet count was observed during CPB similarly in both groups. These findings demonstrated that low-dose aprotinin administration was effective in reducing intraoperative and postoperative blood loss and that activation of the clotting system during CPB was not followed by hyperfibrinolysis in aprotinin-treated patients. The improved hemostasis is mainly attributable to the prevention of hyperfibrinolysis during CPB.

Antifibrinolytic Agents↗

Fluctuating thyroid function depending on the balance between stimulating and blocking types of TSH receptor antibodies: a case report.

A 41-year-old hyperthyroid woman visited the hospital in April 1989. She spontaneously developed hypothyroidism in August 1989 and recurrent hyperthyroidism in November 1991. TSH binding inhibitor immunoglobulins (TBII) and thyroid-stimulating antibodies (TSAb) activities were 34.7% (normal range, < 11.0%) and 295.0% (normal range, < 145.0%), respectively, at her first visit. When she was hypothyroid, TBII were 85.9-90.0%, TSAb were 75-190%, and thyroid stimulation-blocking antibodies (TSBAb) activities were 80.0-96.6% (normal range, < 32.2%). When she became hyperthyroid again, TSAb activities were markedly increased to 1108% with TBII and TSBAb activities being 82.2 and 62.8%, respectively. The results indicate that both stimulating and blocking types of TSH receptor antibodies were present in her serum and that her fluctuating thyroid function could be explained by alterations in the balance between the activities of these two types of antibodies.

Adult↗

Evaluating bronchial drainage pathways in patients with lung disease using digital subtraction angiography.

RATIONALE AND OBJECTIVES: The purpose of the study was to evaluate the venous drainage pathways of the bronchial circulation during bronchial embolotheraphy or infusion therapy. METHODS: The subjects consisted of 21 patients with lung disorders. All of them underwent bronchial arteriography for drug infusion or embolization. Bronchial arteriography was done using both cut-film and digital subtraction methods. RESULTS: The venous drainage pathways of arteriograms could be determined in 15 (71%) patients and classified into the four types: type 1, direct drainage into a pulmonary vein; type 2, drainage into a pulmonary artery with antegrade flow; type 3, drainage into a pulmonary artery with retrograde flow; and type 4, drainage into a bronchial vein. No drainage route could be identified in six (29%) patients. CONCLUSIONS: Digital subtraction angiography can depict the venous drainage pathways in most patients. Drainage occurs into a pulmonary vein in the majority of patients.

Angiography, Digital Subtraction↗

Effects of acute ischemia on anisotropic conduction in canine ventricular muscle.

The effects of acute ischemia on conduction velocities in the longitudinal (theta L) and transverse (theta T) fiber axis were determined from epicardial activation patterns, recorded with 48 bipolar electrodes (plaque electrode, 25 x 35 mm) on the left anterior ventricular wall of eight dogs and the posterior wall of seven dogs. During left ventricular stimulation (cycle length = 300 msec) in the center of the plaque electrode, theta L, theta T, and the ratio of longitudinal to transverse conduction velocities (theta L/T) were measured before and 2 to 5 minutes after occlusion of the left anterior descending coronary artery or the left circumflex coronary artery. During the control state theta L was greater than theta T demonstrating anisotropic properties of cardiac muscle, not only in the anterior but also in the posterior wall. During acute ischemia theta L and theta T were decreased from the control value and theta T was decreased by a greater extent than theta L resulting in an increase in theta L/T from 1.83 +/- 0.31 (mean +/- SD) to 2.19 +/- 0.36 in the anterior wall and from 1.58 +/- 0.17 to 1.92 +/- 0.28 in the posterior wall. During ventricular fibrillation some lines of conduction block were parallel to the long axis of epicardial muscle fiber bundle and the others were perpendicular. In conclusion, acute ischemia increased anisotropic conduction (theta L/T) in the epicardial ventricular muscle mainly due to greater reduction in theta T, in the anterior and the posterior wall. This augmented anisotropic ventricular conduction may have some relation to the initiation of ventricular fibrillation during acute ischemia.

Animals↗

Thyrotropin receptor antibodies in hypothyroid Graves' disease.

To clarify the relation of TSH receptor antibody (TRAb) to Graves' ophthalmopathy and thyroid function, the activities of TSH binding inhibitor immunoglobulins, thyroid-stimulating antibodies, and thyroid stimulation-blocking antibodies were measured in five patients with hypothyroid Graves' disease. The diagnosis was based on the presence of Graves' ophthalmopathy and either permanent or transient hypothyroidism without a history of treatment for hyperthyroid Graves' disease. TSH binding inhibitor immunoglobulins and thyroid-stimulating antibodies were detected in all five patients. Thyroid stimulation-blocking antibodies results indicated that a blocking type of TRAb was not a cause of hypothyroidism. Destructive changes in the thyroid were probably responsible for hypothyroidism, since 1) high antibody titers against thyroglobulin and thyroid microsomal antigen, 2) diffuse hypoechogenicity of the thyroid on ultrasonography, 3) absent or impaired responses of serum T3 after TRH or TSH stimulation, and 4) histological findings similar to those in Hashimoto's thyroiditis were observed. In all patients except one, thyroid function was changeable, with euthyroid and even subclinical hyperthyroid episodes occurring during the course of the illness. It is conceivable that such unstable thyroid function may be attributable to subtle changes in the balance between the effects of destructive changes in the thyroid and the stimulatory effects of TRAb. In conclusion, all patients had TRAb, suggesting a possible relationship between such antibodies and Graves' ophthalmopathy. Patients develop euthyroidism or subclinical hyperthyroidism during the course of the illness with high frequency.

Adult↗

Clinical diagnostic potentials of thyroid ultrasonography and scintigraphy: an evaluation.

This prospective study was designed to evaluate the potential contributions of high resolution ultrasonography (US) and Tc-99m scintigraphy in the routine diagnosis of thyroid disease. The diagnostic impacts of US and Tc-99m scintigraphy results in 177 patients visiting our thyroid clinic were assessed and scored according to the following criteria: when the information provided by either test supported, confirmed or changed the initial clinical diagnosis, they received scores of 2, 3 and 4 respectively, while score 1 was given when the test itself was useless for the differential diagnosis. US identified focal lesions that both palpation and scintigraphy had failed to detect in 14 (12.1%) of 116 patients with diffuse thyroid diseases, suggesting the necessity of routine US examinations in such patients. US scored higher than scintigraphy in the diagnosis of Hashimoto's thyroiditis, adenoma, adenocarcinoma and adenomatous goiter, and vice versa in the diagnosis of hyperthyroid and euthyroid Graves' diseases. Thus, the advantages of US over scintigraphy for morphological evaluation were confirmed. US was particularly useful for the differential diagnosis of adenomatous goiter from Hashimoto's thyroiditis or a single nodular disease. In contrast, scintigraphy gave functional images, being especially helpful for the differential diagnosis of thyrotoxicosis.

Diagnosis, Differential↗

Open heart surgery under total extracorporeal circulation in a patient with advanced glaucoma.

A patient with Wolff-Parkinson-White syndrome and severe glaucoma underwent division of the accessory pathway under total extracorporeal circulation (ECC). During ECC, systolic systemic pressure was maintained at 60-80 mmHg. Arterial pressure in the optic nerve terminal is reported to be half to one-third of systemic arterial pressure and approximates 20 mmHg during ECC. In the case presented, intraocular pressure was maintained below 15 mmHg throughout ECC. Postoperative examination of the patient revealed no change in visual acuity. During ECC, intraocular pressure may exceed the ocular bottom pressure, placing the optic nerve at risk of ischaemia. In cases where optic nerve ischaemia from ECC is likely, preoperative examination by an ophthalmologist is needed.

Adult↗