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Biomedical subjects

K Taniguchi

Publications and source records attributed to K Taniguchi.

At least 595 records · Page 33Linked to original sources

'Radioresistant' CD4-CD8- intrathymic T cell precursors differentiate into mature CD4+CD8- and CD4-CD8+ T cells. Development of 'radioresistant' CD4-CD8- intrathymic T cell precursors.

Using lectin (PNA) and monoclonal antibodies for Pgp-1, IL-2R, H-2k, CD3, and F23.1 (T cell receptor V beta 8), we characterized the 'radioresistant' CD4-CD8- double negative thymocytes at an early stage after 800 rad irradiation. Most of the CD4-CD8- cells on day 8 after irradiation expressed a high level of Thy-1, H-2k, and PNA, while a small proportion of these cells were CD3+ and/or F23.1+. The appearance of Pgp-1 and IL-2R on the 'radioresistant' double negative precursors was also sequentially examined from day 5 to day 9 after irradiation. The double negative thymocytes at day 5 expressed the highest level of Pgp-1 antigens and these cells gradually decreased in number from day 7 to day 9. By contrast, IL-2R was transiently expressed on the double negative cells on the day 7 and 8 after irradiation. These results indicate that progression of thymocyte development occurred within the CD4-CD8- thymocytes after irradiation. We further examined the homing ability of the double negative 'radioresistant' intrathymic T cell precursors to the periphery by intrathymic cell transplantation method. The double negative thymocytes proliferate and differentiate into CD4+CD8+ cells and CD4+CD8- cells but few CD4-CD8+ cells in the thymus, while only CD4-CD8+ cells were detected in the peripheral lymphoid organs 14 days after intrathymic transplantation of the double negative cells in the H-2 compatible Thy-1 congenic mice. These results suggest that the 'radioresistant' intrathymic precursors differentiate and mature in the thymus and migrate to the periphery.

Animals↗

Long term effects of adult-thymectomy on natural killer activity and spontaneous tumor incidence.

Long term effects of adult-thymectomy on both natural killer (NK) activity and spontaneous tumor incidence were investigated in C57BL/6 mice maintained in specific pathogen free atmosphere. As compared with the age matched sham-thymectomized mice, a substantially low incidence of spontaneous tumour (6%) and a high level of splenic NK activity were noted one and a half year later in C57BL/6 mice thymectomized at 6 weeks of age. In contrast, sham-thymectomized mice showed a high incidence of the spontaneous tumor (57%) associated with a low level of splenic NK activity. These results suggest that NK cells play a critical role to prevent the occurrence of spontaneous tumor in vivo.

Age Factors↗

[Clinical evaluation of isosorbide dinitrate (ISDN) spray: a study on the plasma concentrations of ISDN and on its hemodynamic effects using three administration routes].

The effects of ISDN spray has been evaluated using oral, nasal or tracheal routes in patients under enflurane anesthesia. These 30 patients were in ASA I or II physical status without cardiovascular, kidney or liver diseases. Under enflurane anesthesia, hemodynamic parameters (blood pressure and heart rate), blood gas and plasma concentration of ISDN were measured at several points before and after drug administration. The plasma concentration reached a maximum point (C max) 4 min after drug administration in the oral group (O-group) and nasal group (N-group), and the values obtained were 48.4 +/- 5.4 ng.ml-1 and 87.4 +/- 13.8 ng.ml-1 respectively. The C max of the N-group was significantly higher than that of O-group (P less than 0.05). In the O- and N-groups, systolic blood pressure decreased 10% and 17%, after 4 min (P less than 0.05) and recovered 20 after min. Diastolic blood pressure decreased in both groups after 4 min (P less than 0.05). Heart rate significantly increased in the N-group (P less than 0.05), and continued to change up to 60 min after drug administration. In both groups, PaO2/FIO2 decreased 14% and 9% after 10 min (P less than 0.01). In the tracheal group, plasma concentration did not increase and these hemodynamic changes were not observed. These results suggest that nasal route of ISDN spray is the best route of administration.

Administration, Intranasal↗

[Clinical evaluation of midazolam as an anesthetic for geriatric patients and patients with hepatic dysfunction].

This study evaluated the usefulness of midazolam in inducing a anesthetic state in 60 patients who underwent surgery under general anesthesia. The patients were divided into 3 groups; a geriatric group, a hepatic dysfunction group, and a control group (adults without complications). To induce sleep 0.15 mg.kg-1 or 0.2 mg.kg-1 of midazolam was administered intravenously to all three groups. After the administration of midazolam, the mean time for obtaining absence of response to calling name and absence of ciliary reflex were not significantly different in the three groups. The pulse rate and respiratory rate also did not change remarkably. But significant decreases were observed in the systolic blood pressure and tidal volume in all three groups. However, they were not significantly different among the three groups. These results indicate that midazolam is a useful drug for inducing anesthetic state in geriatric patients and patients with hepatic dysfunction.

Adult↗

Serological and genetic characterization of bovine rotaviruses in Thailand by ELISA and RNA-RNA hybridization: detection of numerous non-serotype 6 strains.

A total of 62 fecal specimens positive for rotavirus were collected from diarrheic cows in Thailand in 1988 and 1989. The antigenic properties of rotaviruses in stool were examined by enzyme-liked immunosorbent assays using specific monoclonal antibodies directed at VP4, VP6 or VP7: all the bovine rotavirus strains were determined as subgroup I; none of the strains were reactive with serotype 6-specific monoclonal antibody; and different reactivities of the bovine strains with two anti-VP4 monoclonal antibodies were observed. Polyacrylamide gel electrophoresis of viral RNA exhibited three different RNA electropherotypes. In RNA-RNA hybridization experiments using cell culture-adapted three strains as well as a reference bovine strain (NCDV), RNA from the Thai bovine strains showed very low homology to that from NCDV; only three or four RNA segments were hybridized between the RNAs from Thai samples and NCDV. These results suggested that bovine rotaviruses isolated in Thailand are serologically and genetically distinct from a reference serotype 6 bovine strain, NCDV.

Animals↗

Rapid enzymatic analysis of plasma for tyrosine.

In this rapid, simple, and convenient enzymatic method for measurement of tyrosine in plasma, tyrosine is converted to tyramine by action of tyrosine decarboxylase (EC 4.1.1.25) and the tyramine produced is oxidized to p-hydroxybenzyl aldehyde and hydrogen peroxide by action of tyramine oxidase (EC 1.4.3.9). The hydrogen peroxide is reacted with 4-aminoantipyrine and N-ethyl-N-(2-hydroxy-3-sulfopropyl)-m-toluidine in the presence of peroxidase (EC 1.11.1.7) to obtain quinoneimine dye, the absorbance of which is measured at 570 nm. Thus tyrosine is measured in the visible range. The CV was 4.6% or less, and the measurement was unaffected by other amino acids, except for phenylalanine. The values obtained (y) correlated well with those obtained with an amino acid analyzer (x): y = 0.902x + 3.92 mumol/L (Syx = 12.3; r = 0.985; n = 54).

Autoanalysis↗

[Flow cytometric DNA analysis of pediatric solid tumor].

Ninety nine case of various solid tumors in children were clinically and histologically investigated and the findings were compared with the data obtained by flow-cytometric DNA analysis using paraffin-embedded tumor tissue. Most of the embryonal tumors such as neuroblastoma, nephroblastoma, or medulloblastoma tended to show a diploid DNA stemline (65.2%) in comparison with non-embryonal tumors (45.2%) (p less than 0.025). Aneuploid cases of embryonal tumors in children disclosed histologically rather differentiated appearances, and with a favorable clinical outcome. On the other hand, non-embryonal tumors in children revealed in general an aneuploid DNA stemline and higher rate in high grade malignancy, resembling that of the malignant neoplasms in adult. These prominent features of the flow-cytometric DNA analysis of the embryonal tumors in children suggest that there are some differences in the tumor cytogenetics or histogenesis between the embryonal tumors and the non-embryonal tumors.

Child, Preschool↗

Stimulatory effect of 1,25-dihydroxyvitamin D3 on transferrin synthesis in primary cultures of adult rat hepatocytes.

The effect of 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] on protein synthesis was studied in primary cultures of adult rat hepatocytes, in comparison with those of dexamethasone (DEX). The transferrin (TF) level in the culture medium assayed by a radioimmunoassay (RIA), after incubation for 24 hr was increased in the presence of 1,25-(OH)2D3, significantly at concentrations of more than 10(-12) M and maximally to about 140% of that in control cultures at 10(-8) M, without change in the albumin concentrations, assayed by an EIA. Other vitamin D3 metabolites had similar but weaker effects in increasing transferrin synthesis. On the other hand, incubation with 10(-6) M Dex for 24 hr enhanced the syntheses of both transferrin and albumin. Addition of 10(-7) M actinomycin D did not significantly block the effect of 1,25-(OH)2D3, but did suppress that of dexamethasone. These results indicate that 1,25-(OH)2D3 stimulates TF synthesis of cultured rat hepatocytes with different mechanism(s) of action from that of dexamethasone.

Albumins↗

[Diuretic effects of aminophylline in patients after cardiac surgery].

Diuretic effects of aminophylline in patients after cardiac surgery were studied by using the local renal thermodilution catheter (Goodman Co. Ltd.). The subjects were 11 patients who underwent cardiac surgery in our hospital. All patients had shown almost normal renal and endocrine function. On the day of operation, we indwelld renal thermodilution catheter into the left renal vein under fluoroscopy. After operation, when the urinary volume decreased below 1 ml.kg-1.hr-1, we administered aminophylline at a rate of 2 ml.kg-1.hr-1. We measured HR, BP, CO, PAP, CVP, renal blood flow, urinary volume, urinary electrolytes, plasma renin activity, angiotensin II, aldosteron, ADH and alpha hANP just before and after infusion of aminophylline. The urine volume, renal blood flow and renal blood flow distribution rate showed significant increases of about 70%, 40% and 35% respectively. But hemodynamic parameters including HR, mean BP and CO increased for 5%, 10% and 8% respectively after administration of aminophylline. In the endocrine system, only angiotensin II increased significantly but aminophylline did not cause any change in endocrine system. The results suggest that diuretic effect of aminophylline is mainly achieved by increasing renal blood flow.

Adult↗

[Intraoperative cardiac output monitoring by the transtracheal Doppler method].

We investigated the cardiac output measured with a transtracheal doppler (TTD) tube in surgical patients and evaluated its usefulness during operations. This tube was located at the point where maximum velocity of blood flow was obtained in the ascending aorta. At this point the cross-sectional area of the ascending aorta was calculated and the cardiac output was obtained by multiplying this area with average blood flow velocity which had been ultrasonically determined. The cardiac output by the TTD method was compared with that of the thermodilution method in 10 patients. The results with both groups showed a direct linear correlation. We obtained the following linear equation: TTD C.O. = 0.61 Thermo C.O. + 1.3 C.O.: cardiac output. The direct correlation coefficient proved to be 0.85 at a risk factor of 0.01. The result suggests that this non-invasive TTD method is easily available and useful in monitoring the intraoperative cardiac output.

Aged↗

[A clinicopathological study on patients with bladder cancer treated with cystectomy].

A clinical and histopathological investigation was made on 170 patients with bladder cancer who underwent total cystectomy at our institutions between 1982 and 1986. The overall 5-year survival rates of patients with pTis + pTa, pT1, pT2, pT3, pT3b and pT4 were 100, 71.8, 60.7, 39.2, 31.4 and 0% respectively, those of patients with G1, G2 and G3 were 100%, 67.6%, 35.7% respectively. As for histopathological growth and spread pattern (INF), intramural lymphatic invasion (ly) and venous invasion (v), INF beta, INF gamma, ly2, v (+) showed the worst prognosis. These histopathological factors were considered to be closely correlated to each other. Studies on these histopathological factors are very important in planning the subsequent therapy.

Adult↗

[Lipoperoxidation and antioxidant substances in the human placenta during gestation].

Recently particular interest has been shown in the relationship of the aging phenomenon to lipid peroxidation by free radicals. We studied changes in lipid peroxidation in the human placenta by measuring lipoperoxides from early pregnancy to term. In addition, we studied changes in the activities of superoxide dismutase, catalase, glutathione peroxidase and the concentration of alpha-tocopherol in the placental tissues. The degree of lipid peroxidation in placental tissue in early pregnancy was significantly higher than that in late pregnancy. Lipid peroxidation in the case of spontaneous abortion was slightly higher than that in normal pregnancy. The activities of SOD and catalase increased significantly, but glutathione peroxidase activity remained almost the same throughout development. On the other hand, the alpha-tocopherol concentration decreased gradually as gestation progressed. These results suggest that early placental tissue is functionally immature, then gradually suppresses lipoperoxide formation as pregnancy advances. The placental tissue protects the fetus from many kinds of radicals in the feto-maternal circulation.

Catalase↗

[Late results of CABG for postinfarction angina--relation to preoperative myocardial infarct size].

We evaluated the late results of coronary bypass grafting (CABG) in 85 patients. The patients were divided into two groups according to preoperative MI size estimated by the Selvester QRS score; 24 with MI size of larger than 20% of LV muscle (group A; average 28 +/- 11%), and 61 with MI size smaller than 20% (group B; average 10 +/- 9%). New York Heart Association classes of both groups following CABG improved significantly (from 2.8 +/- 0.7 to 1.3 +/- 0.4 in group A; p less than 0.01, from 2.5 +/- 0.6 to 1.2 +/- 0.5 in group B; p less than 0.01). There was higher incidence of serious ventricular arrhythmias in group A than in group B (83% vs. 21%, p less than 0.01). In Group A, LVEF and LVESVI did not improve following CABG (from 17 +/- 9 to 16 +/- 8 mmHg, from 39 +/- 15 to 40 +/- 15%, from 66 +/- 28 to 69 +/- 40 ml/M2), while in Group B, those improved significantly (from 13 +/- 6 to 11 +/- 5 mmHg; p less than 0.01, from 53 +/- 14 to 58 +/- 10%; p less than 0.01, from 39 +/- 23 to 32 +/- 14 ml/M2; p less than 0.05). The exercise-to-rest LVSWI ratios increased significantly following CABG in both groups (from 86 +/- 25 to 160 +/- 56% in group A; p less than 0.05, from 92 +/- 31 to 140 +/- 37% in group B; p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[The influence of pulmonary regurgitation on left ventricular function after repair of tetralogy of Fallot].

The influence of right ventricular (RV) volume overload by pulmonary regurgitation (PR) on left ventricular (LV) function was evaluated postoperatively in 23 patients with tetralogy of Fallot (TF). The age at operation was 3.1 +/- 1.7 (mean +/- SD) years. The age at postoperative study was 5.9 +/- 2.0 years. We determined RV end-diastolic volume (%RVEDV), RV ejection fraction (EF), %LVEDV, LV end-systolic volume (%LVESV), LVEF, and LV end-systolic stress (ESS)/%LVESV. Patients were divided into 2 groups on the basis of presence or absence of RV volume overload by PR as follows: The %RVEDV (175 +/- 23%) of group 1 (n = 10) was 150% greater than normal RVEDV. Group 2 (n = 13) had normal %RVEDV (108 +/- 23%). Preoperatively, there had been no differences in hemoglobin, %RVEDV, RVEF, %LVEDV, LVEF, and in the ratio of average cross-sectional area of the left and right pulmonary arteries to cross-sectional area of the normal right pulmonary artery between the 2 groups. Moreover, there were no differences in age at repair, or during postoperative study, nor in the postoperative ratio of RV to LV systolic pressure between the 2 groups. RVEF was significantly less in group 1 than in group 2 (0.53 +/- 0.05 vs 0.58 +/- 0.05, p less than 0.05). %LVEDV and %LVESV in group 1, 138 +/- 10% and 171 +/- 30% respectively, were significantly greater than those in group 2, 116 +/- 11% and 133 +/- 20% respectively (p less than 0.001 in %LVEDV and p less than 0.01 in %LVESV).(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiac Volume↗

Evaluation of severity of heart failure using ventilatory gas analysis.

To evaluate the severity of heart failure, cardiopulmonary exercise testing was performed in 99 normal subjects and in 382 patients with cardiac disease. Anaerobic threshold, peak oxygen uptake, and the ratio of increase in oxygen uptake to work-rate increment were determined by ventilatory and gas exchange measurements as indexes for assessing the severity of heart failure. Anaerobic threshold and peak oxygen uptake declined with age, and males showed higher values than females in both indexes. Anaerobic threshold, as the percentage of predicted value for age, sex, and body weight, decreased as New York Heart Association (NYHA) class increased as follows: 90.2 +/- 15.4% in class I, 76.9 +/- 13.8% in class II, and 59.7 +/- 11.9% in class III (mean +/- SD). Although the ratio of increase in oxygen uptake to work-rate increment was not influenced by age or sex, it decreased as the severity of heart disease progressed. These results suggest that indexes from cardiopulmonary exercise testing are closely related to the pathophysiology of heart failure. We conclude that these indexes can be used as objective and reliable parameters for evaluation of the severity of heart failure in terms of functional capacity.

Anaerobic Threshold↗