Biomedical subjects

T Saga

Publications and source records attributed to T Saga.

At least 109 records · Page 6Linked to original sources

PubMed1995

[Two successful cases of total extracardiac right heart bypass].

We reported two successful cases of extracardiac total right heart bypass using 20 mm EPTFE conduit (modified total cavopulmonary connection). They were seven-year-old boy and nine-year-old girl. Both patients had complex heart disease including cyanosis, atrioventricular discordance. We selected this technique instead of modified Fontan or conventional total cavopulmonary connection because of safeness and easiness of surgery and the hemodynamic benefits. They don't have any restriction for their life postoperatively. We propose this technique as an alternative surgical option in candidates for a Fontan procedure or conventional total cavopulmonary connection.

Blood Vessel Prosthesis↗

PubMed1995

Improved myocardial fatty acid utilization after percutaneous transluminal coronary angioplasty.

Exercise-reinjection 201Tl imaging and resting 20-min and 3-hr BMIPP imaging were performed before and 4 mo after percutaneous transluminal coronary angioplasty (PTCA) in a patient with effort angina. Before PTCA, exercise 201Tl imaging showed decreased 201Tl activity in the septal wall, with significant fill-in on the reinjection 201Tl image. The resting 20-min BMIPP image showed decreased activity in the septal wall, with a slight redistribution on the 3-hr BMIPP image. The 201Tl and BMIPP images 4 mo after PTCA showed significant improvement in the 201Tl pattern and BMIPP uptake in the septal wall with no abnormally decreased activities.

Aged↗

PubMed1995

[Cytolysosomes in red blood cells of patients with Behçet's disease at the exacerbation stage].

Peripheral erythrocytes of 5 patients with Behet's disease, not receiving systemic treatment, at the exacerbation stage, and those of 3 healthy controls were investigated with a transmission electron microscope. More than 100 cells were examined per subject. Cytolysosomes (autophagic vacuoles) were frequently observed in cells of the patients. The average frequency of appearance of cytolysosomes was 5.4 +/- 1.5% (mean +/- deviation) in erythrocytes of the 5 patients, and 0.5 +/- 0.4% in those of the 3 control subjects. The difference was statistically significant (p < 0.026). These results suggest that cytolysosomes of erythrocytes may reflect abnormal production or removal involved in the pathophysiology of Behçet's disease.

Adult↗

PubMed1995

[Midterm result of free arterial graft for myocardial revascularization].

Free arterial grafts has been used as grafts for coronary artery bypass grafting (CABG) since April 1993 in our unit and midterm patency was confirmed by coronary angiogram in 32 patients. Of 32 free arterial grafts. 23 right internal thoracic artery grafts (RITAG), 7 gastroepiploic artery grafts (GEAG) and 2 left internal thoracic artery grafts (LITAG) were placed to 38 coronary arteries including 6 grafts for sequential bypass. 20 grafts were placed in the left circumflex artery. 11 to the diagonal branch, 5 to the left anterior descending artery and 3 to the right Free arterial grafts has been used as grafts for coronary artery bypass grafting (CABG) since April 1993 in our unit and midterm patency was confirmed by coronary angiogram in 32 patients. Of 32 free arterial grafts. 23 right internal thoracic artery grafts (RITAG), 7 gastroepiploic artery grafts (GEAG) and 2 left internal thoracic artery grafts (LITAG) were placed to 38 coronary arteries including 6 grafts for sequential bypass. 20 grafts were placed in the left circumflex artery. 11 to the diagonal branch, 5 to the left anterior descending artery and 3 to the right coronary artery. Coronary angiography later than 6 months after operation revealed the patency rate of 100% for LITAG and RITAG and 81.8% for GEAG. In total 36 free arterial graft remained patent and patency rate was 94.7% and the result was comparative to the midterm patency of in situ arterial graft in our series. Free arterial grafts can be expected to offer excellent long term patency and expand the indication of arterial grafts to CABG.

Coronary Angiography↗

PubMed1994

Two-step targeting of experimental lung metastases with biotinylated antibody and radiolabeled streptavidin.

Two-step monoclonal antibody tumor targeting using an avidin-biotin system has unique characteristics because of the high-affinity binding (10(15) M-1) and the lower molecular weight ligands (avidin, streptavidin, or biotin) used as carriers of radioisotopes, toxins, or drugs. The distribution of radiolabeled streptavidin in a two-step targeting strategy was investigated in lung metastases of line 10 carcinoma in guinea pigs. The microdistribution of administered D3 monoclonal antibody and 125I-labeled streptavidin in metastatic nodules was examined by immunohistochemistry and autoradiography, and the uptake was quantitated. With monoclonal antibody pretargeting, streptavidin was found mainly at the periphery of metastatic nodules 1.5 h after injection; it had penetrated deeper at 4 h and was approaching homogeneity in many of the tumor nodules at 24 h. These results indicate that streptavidin can penetrate into metastatic nodules more rapidly than can the antibody. The concentration of streptavidin in metastatic nodules 4 h after injection was 5.6 times higher for the pretargeted group than for the nonpretargeted group, and the pretargeting index was 4.7. Although the absolute uptake of streptavidin had decreased between 4 and 24 h, the metastasis:blood ratio had increased from 1.2 to 2.4. When compared with the animals injected with 125I-labeled D3 antibody alone, the pretargeted group achieved higher tumor:blood and tumor:lung ratios and a higher localization index at early times after injection of the radiolabeled species.

Animals↗

PubMed1994

Streptavidin distribution in metastatic tumors pretargeted with a biotinylated monoclonal antibody: theoretical and experimental pharmacokinetics.

We have developed a pharmacokinetic model for the analysis of a protocol that involves injection of a biotinylated monoclonal antibody followed at a later time by radiolabeled streptavidin. Three distinct physiological spaces are described: an avascular tumor nodule, the normal tissue surrounding the tumor, and the plasma. The model incorporates processes such as plasma kinetics, transcapillary transport, interstitial diffusion, binding reactions, and lymphatic clearances. We have modeled cases in which antigen turnover does not occur, in which antigen turnover does occur (24-h time constant), and in which circulating antibody is cleared from the plasma immediately prior to injection of streptavidin. We have calculated the spatial and temporal distributions of a tumor-specific antibody and of streptavidin in the tumor nodule using parameter values that simulate conditions of recent experiments on metastatic nodules in the guinea pig lung. The theoretical distribution of streptavidin in the tumor nodule shows an initial localization at the periphery that progresses to a fairly uniform distribution throughout the nodule, a temporal sequence that is very similar to experimental observation. This finding indicates that, in a tumor pretargeted with biotinylated antibody, streptavidin can encounter significant retardation in its penetration as a consequence of the high affinity interaction between these two species. Tumor:blood and tumor:lung ratios were calculated and compared to experimental results. In addition, the calculated tumor:blood ratios, tumor:lung ratios, and relative exposures were compared to values obtained from a model of one-step antibody delivery. The two-step protocol yielded an approximately 2- to 3-fold enhancement in these pharmacokinetic indices compared with the one-step method.

Animals↗

PubMed1994

131I-metaiodobenzylguanidine therapy for malignant pheochromocytoma.

131I-metaiodobenzylguanidine (MIBG) therapy was given to five patients with malignant pheochromocytoma. The patients received 1-3 doses of 3.33-4.625 GBq (total dose: 3.7 to 10.73 GBq). Partial tumor regression was observed in two patients, the tumor was unchanged in two patients, and slow progression was noted in one patient. Marked improvement in clinical symptoms was achieved in four patients. The other patient had no symptoms before 131I-MIBG treatment, but the serum epinephrine and dopamine decreased. There were no severe untoward responses in four patients. However, one patient developed transient but severe orthostatic hypotension, hypertension, and hyperglycemia from 1 week to 1 month after 131I-MIBG administration. Although complete remission was not obtained, all the patients achieved some benefit from 131I-MIBG therapy. Thus, 131I-MIBG appears to be useful for the palliation of malignant pheochromocytoma.

3-Iodobenzylguanidine↗

PubMed1994

Bivalvation with bridging for common atrioventricular valve regurgitation in right isomerism.

A child with regurgitation in the common atrioventricular valve associated with complex heart disease underwent bivalvation with bridging for common atrioventricular valve regurgitation and arterial-pulmonary shunt for low pulmonary blood flow. Postoperative cardiac catheterization and color Doppler echocardiography revealed elimination of atrioventricular valve regurgitation and ventricular enlargement, reflecting an increase in pulmonary artery blood flow. We describe the concept and technique of bivalvation with bridging for common atrioventricular valve regurgitation.

Child↗

PubMed1994

Application of high affinity binding concept to radiolabel avidin with Tc-99m labeled biotin and the effect of pI on biodistribution.

In order to label avidin with Tc-99m, we took advantage of the high affinity binding of biotin to avidin; we radiolabeled a biotin derivative with Tc-99m and then bound this Tc-99m labeled biotin derivative to avidin. For our labeling approach, N epsilon-biotinyl-L-lysine (Biocytin) was reacted with the N-hydroxy-succinimide ester of benzoylmercaptoacetyltriglycine (Bz-MAG3). The resulting Bz-MAG3-Biocytin was labeled with Tc-99m using Tc-99m glucarate as a Tc-99m transchelating agent and mixed with avidin at a 1:1 molar ratio resulting in almost a quantitative labeling yield. Tc-99m-MAG3-Biocytin/Avidin was stable in serum at 37 degrees C with 97 and 95% of the total Tc-99m activity still bound to avidin at 2 and 24 h, respectively. The biodistribution of Tc-99m-MAG3-Biocytin/Avidin in normal Balb/c mice showed a high liver and kidney uptake with 56.6 and 28.9%, respectively at 10 min. We attempted to lower the liver and the kidney activities by reducing the isoelectric point (pI) of avidin by conjugating succinic acid moieties at lysine residues of avidin (pI 10). The kidney uptake decreased to 19.0, 3.1 and 1.7% when the pI of avidin was reduced to 7.0-9.3, 5.5-6.2 and 4.0-4.8, respectively. The lowering of the pI, however, did not change the liver activity appreciably.

Animals↗

PubMed1994

Relationship between various parameters derived from 123I-labelled beta-methyl-branched fatty acid whole-body scintigraphy and left ventricular ejection fraction in patients with ischaemic heart disease.

Heart uptake and clearance of 123I-15-(p-iodophenyl)-3(R,S)-methyl- pentadecanoic acid (BMIPP) by whole-body scintigraphy in relation to left ventricular ejection fraction (LVEF) was evaluated in 34 patients with ischaemic heart disease. At 45 and 210 min after injection, anterior whole-body images were obtained. In each patient, multigated blood pool scintigraphy was also performed, and LVEF was calculated. The percentage heart uptake of BMIPP did not have a significant correlation with LVEF (R = -0.299, NS). In contrast, there was a positive correlation between LVEF measured by multigated blood pool scintigraphy and BMIPP count density of the heart (R = 0.467, P = 0.005). Myocardial BMIPP washout rate also positively correlated with LVEF (R = 0.472, P = 0.005). In addition to these observations, there was a positive correlation between the BMIPP count density of the heart and myocardial BMIPP washout rate (R = 0.0543, P = 0.001). Thus, the BMIPP count density of the heart and myocardial BMIPP washout rate derived from BMIPP whole-body scintigraphy directly correlated with LVEF. However, the correlations between these parameters and LVEF were not strong enough to allow left ventricular dysfunction to be assessed precisely.

Adult↗

PubMed1994

[Changes in platelet count and mean volume of platelet after administration of icosapentaenoic acid ethyl-ester, and factors that may affect those changes].

A total of 34 patients, aged 43 to 86 years old (mean 65), consisting of 26 males and 8 females, with thrombotic or arteriosclerotic diseases were orally given highly purified eicosapentaenoic acid ethyl-ester formulation (IPA-E) for 12 weeks without changing regular food intake. Changes in platelet count (PLT), mean platelet volume (MPV), platelet-crit (Pct) and change of distribution width of platelet size (PDW), and factors affecting the changes were studied administration, dose of IPA-E, age, sex, smoking habits, complications of diabetes mellitus and hyperlipidemia, and concomitant drugs such as calcium antagonists or diuretics. With daily administration of 1800 or 900 mg of IPA-E, PLT and Pct began to decrease after four weeks and decreased significantly after eight weeks until the completion of administration. After the 12th week, the MVP became smaller than the preadministration level, while PDW did not change significantly during the entire period of administration. The volume and rates of changes in PLT, MPV and Pct during administration for 12 weeks correlated negatively with those preadministration values. The PLT, MPV and Pct decreased significantly in both the 1800 and 900 mg groups compared to values before administration. There were no significant differences in changes between the two groups. The plasma IPA concentration in the 12th week of the 1800 mg group was significantly higher than that of the 900 mg group. The rate of changes in Pct had a significantly negative correlation with the achieved IPA concentration. The age, smoking habits, complications of diabetes mellitus, or concomitant drugs of calcium antagonists or diuretics did not affect the changes of platelet parameters significantly. The PLT and Pct in male patients decreased significantly, but no significant changes were observed in female patients. The PLT and Pct in patients with IIb and IV hyperlipidemia decreased significantly compared to those in normolipidemic or IIa hyperlipidemic subjects. The study demonstrated that IPA-E improved platelet parameters, suggesting IPA-E could prevent progression of thrombotic and arteriosclerotic diseases, IPA-E was particularly effective in male patients or patients with Type IIb or IV hyperlipidemia. Although a daily dose of 900 mg was effective, 1800 mg was even more effective.

Adult↗

PubMed1994

[A successful case of repeated prosthetic valve re-replacement for somatic growth in childhood].

The patient who had had systemic atrio-ventricular valve replacement with Björk-Shiley 19 M at the age of 4 years was treated successfully with repeated re-replacement with St. Jude Medical 23M and St. Jude Medical 27M at the age of 8 years and 16 years respectively, because of his somatic growth. Two size larger valve was easily replaced at each operation. The original disease of this patient was corrected transposition of the great arteries with ventricular septal defect and regurgitation of the left atrio-ventricular valve caused by Ebstain anomaly and severe pulmonary hypertension. This case revealed that the annulus of the atrio-ventricular valve would grow even when fixed to the prosthetic valve sawing ring, thereby permitting the use of a larger-sized valve at the time of second and third prosthetic valve re-replacement.

Adolescent↗

PubMed1994

[A case of idiopathic pulmonary hemosiderosis of adult onset].

A 69-year-old woman suddenly suffered massive hemoptysis and was admitted to the hospital. The test of anti-glomerular basement membrane antibodies was negative. Chest radiograph showed diffuse infiltrative shadows similar to those of lung edema in the both lung fields. The patient's condition worsened gradually during the next 3 weeks, with repeated massive hemoptysis. Steroid pulse therapy had limited effects on the progressive respiratory failure, and the patient died. Autopsy showed alveolar hemorrhage and macrophages containing haemosiderin. Immunofluoresence microscopy showed no deposits of immunoglobulin in the kidney. Idiopathic pulmonary hemosiderosis of adult onset with acute respiratory failure is rare in Japan.

Age of Onset↗

PubMed1994

[Prevalence of specific IgE antibodies for Dermatophagoides farinae and six inhalants in the general population].

A seroepidemiologic study of house dust allergy and pollinosis was performed among a general population aged 17 to 69 in Aichi Prefecture, Japan. The prevalence of blood containing IgE antibodies to four perennial antigens and three seasonal antigens was examined among 198 persons whose serum total IgE antibodies were above 40 IU/ml. The prevalence of blood containing IgE antibodies was from 9 to 18 percent among perennial antigens and from 6 to 30 percent among seasonal antigens. These results show that Dermatophagoides farinae, Cryptomeria japonica pollen and Anthoxanthumodoratum pollen are important antigens in this population.

Adolescent↗

PubMed1994

Effect of metabolism on retention of indium-111-labeled monoclonal antibody in liver and blood.

UNLABELLED: The effect of a chelator structure on the metabolic fate of the 111In-labeled monoclonal antibody (Mab) T101 was investigated in normal Balb/c mice to assess the importance of this chemical parameter in the reduction of the background radioactivity in blood and liver. METHODS: Mab T101 was conjugated with either 2-(p-isothiocyanatobenzyl)-6-methyl-diethylaminetriaminepentaac etic acid (DTPA) (1B4M), 2-(p-isothiocyanatobenzyl) cyclohexyl-DTPA (CHX-B) or cyclic DTPA dianhydride (cDTPA) and then radiolabeled with 111In. Normal mice were injected intravenously with these 111In-labeled T101 conjugates and sacrificed in groups of five up to 5 days postinjection for comparative biodistribution studies and analyses of liver, blood and urine samples for radioindium products. RESULTS: The biodistribution of 111In-1B4M-T101 and 111In-CHX-B-T101 were similar to each other but significantly different from that of 111In-cDTPA-T101, particularly in the blood and liver. Size-exclusion high-performance liquid chromatography indicated that the concentration of the intact 111In-immunoglobulin (Ig)G in liver decreased with similar rates for the three conjugates. Meanwhile, the concentration of a small DTPA-like metabolite in liver increased to a different peak value (4.6% ID/g for the cDTPA conjugate and 1.6% ID/g for the 1B4M and CHX-B conjugates) approximately at 24 hr and maintained a steady-state concentration up to 5 days. CONCLUSION: The thiourea linkage between T101 and the 111In-labeled chelates and a higher complex stability and higher lipophilicity of 111In-1B4M and 111In-CHX-B appear to be responsible for lower liver and higher blood radioactivity for the 1B4M and CHX-B conjugates.

Animals↗

PubMed1994

Kinetics of iodine-123-BMIPP in patients with prior myocardial infarction: assessment with dynamic rest and stress images compared with stress thallium-201 SPECT.

UNLABELLED: Myocardial kinetics of 123I-labeled 15-(p-iodophenyl)3R, S-methylpentadecanoic acid (BMIPP) were evaluated with dynamic SPECT, and stress and rest BMIPP images were directly compared in conjunction with stress 201Tl. METHODS: We studied 26 patients with prior myocardial infarction. Two minutes after injection of BMIPP, dynamic data acquisition with a three-headed SPECT was started and continued for 12 min. Conventional SPECT images were obtained at 20 min and 3 hr after injection. On a separate day, exercise, stress 201Tl SPECT was performed at 10 min and 3 hr after injection. Exercise stress-BMIPP imaging was performed in 15 of the patients, and static SPECT images were obtained. RESULTS: With dynamic SPECT, early clearance of BMIPP from the myocardium was observed in the segments with reversible 201Tl defects, suggesting enhanced contribution of backdiffusion from BMIPP. In myocardial segments with reversible 201Tl defects, 20-min BMIPP images showed a higher frequency of reduced uptake when compared to 3-hr 201Tl (90/163) imaging. CONCLUSION: With BMIPP dynamic SPECT, an enhanced contribution of backdiffusion in the early phase from ischemic myocardium was suggested. When exercise stress BMIPP images were obtained, a more severe defect was observed than on rest BMIPP and stress 201Tl imaging, possibly due to decreased coronary blood flow and impaired fatty acid uptake induced by ischemia during exercise.

Exercise Test↗

PubMed1993

Salmonid pituitary gonadotrophs. III. Chronological appearance of GTH I and other adenohypophysial hormones in the pituitary of the developing rainbow trout (Oncorhynchus mykiss irideus).

The first appearance of adenohypophysial cells in the developing rainbow trout embryo was studied by immunocytochemistry. Antibodies generated against the beta subunits of coho salmon gonadotropins (GTH I and GTH II), the beta subunit of human thyroid stimulating hormone (TSH), chum salmon prolactin (PRL), chum salmon growth hormone (GH), and synthetic alpha-MSH were used as immunocytochemical probes. The pituitary anlage was first recognized at developmental stage 21 (18 days postfertilization). At this stage, immunoreactive (ir) PRL and alpha-MSH cells were identified in the rostral and caudal regions of the pituitary, respectively. Cells containing ir-GH and ir-adrenocorticotropin (ACTH) appeared at stage 28 (35 days postfertilization). At the last stage before hatching (stage 29, 42 days postfertilization) ir-TSH cells were identified. Ir-GTH I cells were first observed in the pituitary at stage 32 (15 days after hatching), when mitosis of gonadal germ cells also was observed. At stage 35 (35 days after hatching), meiotic figures were first observed in a few germ cells of some fish indicating that gonadal sex differentiation probably begins at about this time. Cells containing ir-GTH II were not apparent in the pituitary at any stage of embryonic or larval development (up to stage 35) and were not present in pituitaries of trout at 6 months of age when the ovaries were in the perinucleolus stage and when only spermatogonia, but no spermatocytes were present in the testis. These observations suggest that GTH I, but not GTH II, may regulate initial gonadal growth and development in the embryonic and larval rainbow trout.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenocorticotropic Hormone↗

PubMed1993

A human/mouse chimeric monoclonal antibody against CA125 for radioimmunoimaging of ovarian cancer.

Murine monoclonal antibody 196-14 recognizes the ovarian-cancer-associated antigen CA125, but the epitope it recognizes is different from that of monoclonal antibody OC125. We developed a human/mouse chimeric 196-14 using the variable regions of the murine 196-14 and human heavy-chain (gamma 1) and light-chain (kappa) constant regions. Cell binding and competitive inhibition assays using chimeric 196-14 labeled with 125I, 111In or 99mTc demonstrated that the in vitro immunoreactivity of the chimeric antibody was identical to that of the parental murine monoclonal antibody. However, in mice bearing human ovarian cancer xenografts, the clearance from blood was faster and absolute levels of accumulation in the tumor were lower for the 125I-labeled or 99mTc-labeled chimeric antibody than for the murine antibody labeled with the corresponding radionuclides. The tumor-to-blood radioactivity ratio was not significantly different between the chimeric antibody and the murine antibody, regardless of the radionuclide used for labeling. Chimeric antibody 196-14 labeled with 131I, 111In or 99mTc is promising for the radioimmunoimaging of ovarian cancer.

Adenocarcinoma↗