Evaluation of an immunoassay method for the determination of urinary collagen crosslink excretion.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to K Hata.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
We examined the effects of a novel water-soluble forskolin derivative, NKH477 (0.5 microgram/kg/min), on arterial-ventricular (A-V) coupling and mechanical energy transduction from heart to circulatory bed in comparison with those of dobutamine (3 micrograms/kg/min) in 8 patients with left ventricular (LV) systolic dysfunction using a conductance catheter method. A-V coupling was assessed as the ratio of the effective arterial elastance (E(a)) to the slope of the end-systolic pressure-volume relation (ESPVR) (E(max), left ventricular contractility index), and the ratio of mechanical energy transduction was obtained as the fraction of PV area (PVA) comprised of stroke work (SW). E(max) (2.59 mm Hg/ml/m2), E(a)/E(max) (1.62), and SW/PVA (0.58) were impaired in control contractile state. NKH477 increased Emax to the same extent as dobutamine. E(a) decreased with NKH477 but not with dobutamine. As a consequence, the decrease in E(a)/E(max) with NKH477 was greater than that with dobutamine (52 vs. 47%, p < 0.05); the increase in SW/PVA with NKH477 was also greater than that with dobutamine (28 vs. 21%, p < 0.05). These findings suggest that NKH477 may be a superior alternative to dobutamine in A-V coupling and mechanical energy transduction in patients with LV systolic dysfunction.
Explore the source record for details and available documents.
Of 471 patients undergoing a complete resection for non-small-cell carcinoma of the lung between 1972 and 1989, 40 patients (8.5%) had local recurrences without extrathoracic distant metastasis. Excluding 8 patients who had malignant pleural effusion, we selected 32 patients (24 with hilar-mediastinal lymph node, 6 with bronchial stump, and 2 with chest wall recurrence) from the 40 patients and assessed the significance of local control by radiotherapy. The median length of survival after disease recurrence for these 32 patients was 19 months. Of 29 patients given radiation treatment, 16 who responded to the treatment survived significantly longer than nonresponders (median survival time 27 months versus 6 months, p < 0.01). Univariate analyses of survival after recurrences in relation to various factors revealed that sex and disease-free intervals were significant prognostic factors (p < 0.05) other than the effect of radiotherapy. A multivariate analysis showed that the effect of radiotherapy was the predominant prognostic factor. From these results, we conclude that local control with radiation is beneficial in patients with solely locally recurrent tumors in terms of improved survival.
Previous studies on lymphocyte cytotoxicity against autologous human hepatocytes had been studied using Terasaki plates, in which dead hepatocytes after incubation with lymphocytes were counted visually. No studies with 51Cr-labeled human hepatocytes as targets have been reported, although it can give us more objective results. In the present study, we established procedures for labeling human hepatocytes with 51Cr and for measuring cytotoxicity of freshly isolated liver-infiltrating lymphocytes (LIL) against 51Cr-labeled human autologous hepatocytes. Hepatocytes were isolated from diseased and 'normal' liver tissues, cultured overnight, and labeled with 51Cr 'in situ' in the wells of 96-well round bottom plates. Human hepatocytes isolated from either 'normal' or diseased liver tissues labeled well with 51Cr, and mean spontaneous 51Cr release was less than 15% in the presence of 5% fetal bovine serum or human AB serum. Freshly isolated LIL obtained from chronic viral hepatitis but not from other liver diseases showed cytotoxicity against 51Cr-labeled autologous hepatocytes in 4 h 51Cr release assays, and the percent specific lysis was linearly related to the E:T cell ratio. LIL from viral hepatitis were able to mediate natural killer (NK) activity against K562 targets, lymphokine-activated killer-like activity against Daudi cells, and lectin-dependent cellular cytotoxicity. Two-color flow cytometry analysis showed that these LIL contained both CD3+ T cells and CD3-CD56+ NK cells. This is the first report which examined the cytotoxicity of liver-infiltrating lymphocytes against 51Cr-labeled human hepatocytes, and it will be useful in assessing local immune response against autologous hepatocytes in chronic liver diseases.
Using color and pulsed Doppler ultrasonography, arcuate arterial velocimetry was carried out in 91 normal women, at 16-40 weeks, menstrual age. The arcuate arterial hemodynamics was assessed by the calculation of the resistance index (RI). A curvilinear relationship was found between the RI value of the arcuate artery obtained from the placental site in the uterus and menstrual age (R2 = 0.328). The relationships between the RI value of the arcuate artery obtained from the nonplacental site (R2 = 0.268) or the averaged RI value between the placental and nonplacental sites (R2 = 0.321) and menstrual age were both linear. Normal ranges of RI values of arcuate arteries during pregnancy for the placental site, nonplacental site, and their average values were generated. These results provide a foundation for evaluating uteroplacental velocimetry in normal pregnancy using Doppler ultrasonography.
The outcome of eight patients with invasive thymoma accompanying pleural dissemination was investigated. Only two patients had mediastinal tumor resection and pleural disseminated tumor excision. Seven patients underwent radiotherapy to the mediastinum and/or disseminated tumors. A clinical response to radiotherapy was achieved in the six patients with evaluable lesions (complete response in five patients and partial response in one). The estimated 5-year survival rate was 87.5%. Four patients were alive more than 10 years. So far, the mediastinal tumors of seven patients have been controlled for periods ranging from 42 to 154 months. Recurrence in six patients appeared as pleural tumors. Four out of the six patients had five courses of radiotherapy to the recurrent pleural tumors, four of which achieved complete response. No distant metastases were observed at any time. These observations suggest that radiotherapy should be the primary mode of treatment in cases of invasive thymoma with pleural dissemination.
The inhibitory effect of various compounds on the activities of four types of rat sialidase was investigated. 2-Deoxy-2,3-dehydro-N-acetylneuraminic acid and N-acetylneuraminic acid were competitive inhibitors for the sialidases. The former was effective against cytosolic sialidase and intralysosomal sialidase more than two membrane-associated sialidases I and II, the latter being a much weaker inhibitor. A heavy metal ion such as Cu2+ (1 mM) and thiol-modifying 4-hydroxymercuribenzoate (50 microM) caused complete inhibition of the activities of cytosolic sialidase and membrane sialidase I, while no decrease in the activities of intralysosomal sialidase and membrane sialidase II was observed. When 4-nitrophenyloxamic acid and siastatin B, inhibitors of bacterial sialidases, and synthetic thioglycoside GM3 analogue Neu5Ac alpha-s-(2-6)Gal beta(1-4)Glc beta(1-1) ceramide, an inhibitor of influenza virus sialidase, were tested, they did not affect any activity of the rat sialidases. By the differential effect of these inhibitors, the four types of rat sialidase could be discriminated from one another and furthermore from viral and bacterial sialidases.
Explore the source record for details and available documents.
Several investigators have found experimentally that the force-time integral varies non-linearly with energy expenditure over the course of a cardiac contraction. Also, recent research findings have indicated that the crossbridge cycle to ATP hydrolysis ratio in muscle fiber systems may not be coupled with a one-to-one ratio. In order to investigate these findings, Huxley's sliding filament crossbridge muscle model coupled with parallel and series elastic components was simulated to examine the behavior of the crossbridge energy utilization and force-time integral vs time. Crossbridge (CB) energy utilization was determined by considering the ATP hydrolysis for the crossbridge cycling, and this CB energy was compared with the force-length energy in a contraction. This CB energy was calculated in both isometric and isotonic contractions as a function of contraction time and compared to the force-time integral. Simulation results demonstrated that the ratio of the force-time integral to CB energy varies strongly throughout the cardiac cycle for both isometric and isotonic cases, as has been observed experimentally. Simulations also showed that using the force-length energy component of energy vs the CB energy gave a better correlation between the total energetic predictions and the force-time integral, agreeing with recent finding that the crossbridge cycle to ATP hydrolysis ratio may not be coupled one-to-one, especially at lower force levels.
OBJECTIVES: The aim of this study was to compare the effects of a phosphodiesterase inhibitor and catecholamine on arterial-ventricular coupling and myocardial energetics in the diseases human heart. BACKGROUND: Recent experimental studies have indicated that the arterial-ventricular coupling analysis using the time-varying elastance model could discriminate between inotropic and vasoactive effects of the two agents. METHODS: With the use of a conductance catheter, left ventricular contractility and arterial afterload were measured from the slope of the end-systolic pressure-volume relation, Emax, and the slope of the end-systolic pressure-stroke volume relation, Ea. Arterial-ventricular coupling was assessed by Ea/Emax before and after administration of a new phosphodiesterase inhibitor, E-1020 (0.3 microgram/kg per min), and a beta 1-stimulant, dobutamine (5 micrograms/kg per min), in 20 patients with heart disease. Left ventricular mechanical efficiency was assessed as the ratio of stroke work to myocardial oxygen consumption per beat measured by the thermodilution method. RESULTS: The slope of the end-systolic pressure-volume relation increased comparably with both E-1020 (39%, p < 0.01) and dobutamine (47%, p < 0.01), but Ea/Emax decreased with E-1020 (1.25 to 0.78, -37%, p < 0.01) more than with dobutamine (1.23 to 0.99, -16%, p < 0.05). Although stroke work index increased with both agents, myocardial oxygen consumption remained unchanged with E-1020 but increased with dobutamine (p < 0.05). Consequently, left ventricular mechanical efficiency increased with E-1020 (0.30 to 0.36, p < 0.05) but remained unchanged with dobutamine (0.27 to 0.29, p = NS). CONCLUSIONS: The phosphodiesterase inhibitor E-1020 improved arterial-ventricular coupling more than did dobutamine, with a resultant increase in mechanical efficiency. These data were in accordance with the theoretic prediction of the coupling analysis in the diseases human heart.
OBJECTIVES: This study was designed to assess the relation between left ventricular regional myocardial oxygen consumption (VO2) and variables of regional myocardial contractile function under various loading conditions. BACKGROUND: Although the relation between global VO2 and global ventricular function has been extensively studied, the relation between regional VO2 and regional myocardial contraction is not fully understood. METHODS: Myocardial shortening (regional area shrinkage), regional work, regional total mechanical energy index and regional VO2 were measured under variously altered loading conditions in the isolated, blood-perfused dog left ventricle. Regional total mechanical energy per beat was quantified by wall tension-regional area area (TAA) by the analogy of left ventricular pressure-volume area. Left ventricular loading conditions were altered by changing end-diastolic volume and stroke volume with a servo pump as follows: 1) increased preload (increased end-diastolic volume and stroke volume at a constant ejection fraction), 2) decreased afterload (increased stroke volume at a constant end-diastolic volume), 3) increased preload and afterload (increased end-diastolic volume at a constant stroke volume), and 4) altered mode of contraction (ejecting vs. isovolumetric contractions). RESULTS: During increased preload, all three variables correlated positively with regional VO2 (r = 0.78 to 1.00). During decreased afterload, the correlation was negative for area shrinkage (r = -0.65 to -0.91) and variable for regional work (r = -0.55 to 0.98) but positive and highly linear for TAA (r = 0.80 to 0.99). During increased preload and afterload, the correlation was again negative for area shrinkage (r = -0.77 to -0.97) but positive for regional work (r = 0.83 to 0.93) and TAA (r = 0.95 to 0.99). During altered mode of contraction, the correlation was insignificant for area shrinkage (r = 0.24 to 0.57) and moderate for regional work (r = 0.50 to 0.79), whereas again highly linear for TAA (r = 0.95 to 0.98). Thus, only TAA correlated closely with regional VO2 under any loading conditions. Furthermore, the slope and regional VO2 intercept of the regional VO2-TAA relation was remarkably consistent among the different hearts and loading conditions. CONCLUSIONS: We conclude that there is a tight coupling between regional VO2 and regional total mechanical energy represented by TAA regardless of left ventricular afterload and preload conditions.
To study the effects of osteoblast products on osteoclast formation, we added the conditioned medium (CM) of rat osteoblastic cell line ROS17/2.8 to rat bone marrow cultures, in which tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like multinucleate cells (MNCs) formed in the presence of 10(-8) M 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). The formation of 1,25(OH)2D3-dependent TRAP-positive MNC at day 7 of culture was strongly inhibited by the > 10 kDa fraction of ROS17/2.8 cell-CM (ROSCM), but heat treated ROSCM (htROSCM) expressed marked stimulation in the formation of the MNCs. The expression of several osteoclastic phenotypes of the MNCs induced by htROSCM and 1,25(OH)2D3 was more enhanced compared with that of the MNCs induced by 1,25(OH)2D3 alone. The MNCs induced by htROSCM and 1,25(OH)2D3 were highly motile, were sensitive to calcitonin (CT), and had high bone resorbing activity. These data suggest that htROSCM promotes the osteoclast differentiation in the presence of 1,25(OH)2D3 in a rat bone marrow culture system. The stimulatory activity of TRAP-positive MNC formation in htROSCM is derived from heat-stable protein(s) that is (are) thought to be different from colony-stimulating factors (CSFs) such as macrophage-CSF (M-CSF) or granulocyte-macrophage-CSF (GM-CSF).
Growth of the fetal adrenal gland has been monitored by measurements of the circumference (AGC) and area (AGA) of the adrenal gland from 16 to 40 weeks menstrual age. Growth curves for these parameters have been determined using a Rossavik growth curve models [P = c(t)k + s(t)]. R2 values of 86.2 and 91.1% were obtained for AGC and AGA, respectively. Variability analysis indicated a progressive increase in variability with menstrual age for these two parameters. Variability data were used with the growth curve models to determine standard curves for AGC and AGA. These standard curves provide a superior means for evaluating the adrenal growth in the fetus and the fetal status in utero in high-risk pregnancies.
Echocardiographic assessments of fetal and neonatal systolic time intervals were made to determine differences in circulatory changes in 40 neonates delivered vaginally and 30 delivered by elective cesarean section. Left preejection period (LPEP), left ventricular ejection time (LVET), LPEP/LVET, right preejection period (RPEP), right ventricular ejection time (RVET), RPEP/RVET, and heart rate were determined at various time points from antenatal to 120 hours after delivery. There were no significant changes in left systolic time intervals between the two groups at any various time points. However, RPEP and RPEP/RVET values were significantly higher in the cesarean section group than in those in normal vaginal delivery group within 12 hours after delivery. These results suggest that the transient pulmonary hypertension after delivery is prolonged in babies delivered by elective cesarean section.