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Biomedical subjects

H Kishimoto

Publications and source records attributed to H Kishimoto.

At least 343 records · Page 19Linked to original sources
PubMed1976

Zonation of the adrenal cortex. III. Distribution of cytochrome P-450 in the zona glomerulosa of the bovine adrenal cortex.

A microsomal fraction was obtained from the zona glomerulosa of the bovine adrenal cortex. Glucose-6-phosphate activity of the fraction was found to be much lower than that of the liver. Contents of RNA and phospholipids, besides electron microscopic findings, of the fraction also indicate that it is rich in smooth-surfaced endoplasmic reticulum. Distribution of cytochrome P-450 in the zona glomerulosa was studied using various fractions including the microsomal fraction described above. The amount of cytochrome P-450 in mitochondria and that in microsomes were determined to be 0.73 and 0.32 nmoles/mg protein, respectively. The CO-difference spectrum was affected not only by the concentration of added deoxycholate but also by the incubation time after addition. Approximately 40-50% of cytochrome P-450 in the samples were converted to cytochrome P-420 within 20-30 seconds of incubation with deoxycholate.

Adrenal Cortex↗
PubMed1976

Zonation of the adrenal cortex. I. Isolation of mitochondria from the zona glomerulosa of the bovine adrenal cortex.

Isolation procedures for mitochondria from the zona glomerulosa of the bovine adrenal cortex are described in comparison to those isolated from the zona fasciculo-reticularis. The cristal membranes of mitochondria in the zona glomerulosa in situ are tubular or tubulo-vesicular, whereas those of mitochondria in the zona fasciculo-reticularis in situ are vesicular. When mitochondria are isolated from the former zone, they invariably showed a condensed configuration regardless of isolation media, whereas those isolated from the later zone in a ST medium showed an orthodox configuration. When Ca2+ was added to mitochondria isolated form either zone in an STE medium in the condensed configuration, transition from the condensed to the orthodox configuration took place; the cristel membrane of mitochondria from the zona glomerulosa became tubular or tubulo-vesicular and those of mitochondria from the zona fasciculo-reticularis became vesicular. Purity of mitochondria thus obtained from the zona glomerulosa was examined by electron microscope and marker enzymes. Coupling efficiency of mitochondria was found to be remarkably affected by temperature during the isolation procedures and a choice of substrates.

Adrenal Cortex↗
PubMedDate not supplied

Thyroid nodules: re-evaluation with ultrasound.

The purpose of this study was to clarify ultrasound (US) evaluation of microcalcifications and determine whether the calcifications seen in US scans can reliably predict malignant thyroid tumors. Diagnostic accuracy of microcalcification and other various signs seen in US scans for predicting malignancy was evaluated prospectively in 259 pathologically verified thyroid nodules. Sonographic and pathologic correlation of calcifications was performed on 69 of 99 surgically removed nodules. Pathologic studies revealed that hyperechoic areas with acoustic shadowing represented mostly amorphous dense calcifications and sometimes microcalcifications, but small particles without acoustic shadowing mainly reflected microcalcifications and sometimes large amount of fibrous bands and condensed colloids. Of the various sonographic signs, microcalcification showed the highest accuracy (76%), specificity (93%), and positive predictive value (70%) for malignancy as a single sonographic sign, but its sensitivity (36%) was poor. Although sonographic microcalcification showed relatively high specificity, the accuracy of this finding for malignancy was insufficient.

Adenoma↗
PubMedDate not supplied

Morphologic analysis of common atrioventricular valves in patients with right atrial isomerism.

The objective of the study was to examine the relation between the morphology of the common atrioventricular valve and regurgitation of the valve in patients with right atrial isomerism. We examined seven consecutive patients with documented right atrial isomerism who subsequently underwent postmortem examination during a 10-year period. The degree of regurgitation and the diameters of the common valve were evaluated via cineangiography, and the site of regurgitation was evaluated by echocardiography. The morphology of the common atrioventricular valve was assessed further at autopsy. Cineangiography revealed valve diameters ranging from 14.8 to 27.8 mm (mean 20.9 mm). Valvar regurgitation was revealed within 2 months of birth in all patients. Regurgitation abruptly worsened in three patients after placement of a Blalock-Taussig shunt or a central shunt and postintubation. Autopsies revealed that the common atrioventricular valve consisted of four leaflets in five patients, and three leaflets in two. The anterior leaflets were large and protruding in all patients, and the lateral leaflets were thickened in six. All patients had a mass consisting of the left lateral leaflets and chordae with direct attachment of the chordae to the ventricular muscle (the right lateral leaflet was attached to the ventricular muscle and immobile in one patient). The lateral leaflets clung to the ventricular wall and exhibited poor movement in six patients. Leaflets with poor mobility corresponded to the regurgitant valvar site as assessed by echocardiography in six patients; and the regurgitation in three patients with acute deterioration occurred at the valvar side with poor mobility. It is concluded that the common atrioventricular valve in patients with right atrial isomerism has morphologic characteristics that may be associated with valvar regurgitation and malignant potential for abrupt deterioration after replacement of systemic-pulmonary shunting.

Cadaver↗
PubMedDate not supplied

Detection of hypervascular hepatocellular carcinoma by dynamic MRI and dynamic spiral CT.

OBJECTIVE: Our goal was to evaluate the detectability of hypervascular hepatocellular carcinomas (HCCs) by multislice dynamic MRI and dynamic spiral CT. MATERIALS AND METHODS: Prior to transcatheter arterial chemoembolization (TACE) with iodized oil, the liver was subjected to T1- and T2-weighted SE-MRI, multislice dynamic MRI after intravenous bolus injection of Gd-DTPA, early phase imaging with spiral CT (dynamic spiral CT) after intravenous bolus injection of contrast medium (at a rate of 2 or 3 ml/s), and delayed phase CT in 64 patients with 208 HCC nodules. The detectability of HCCs by MRI and CT was evaluated retrospectively compared with CT after TACE as a gold standard. RESULTS: The detectability of nodules < 1 cm in diameter was superior with dynamic MRI (67%) and dynamic spiral CT (50%) in comparison with SE-MRI (26%) and delayed phase CT (11%) (p < 0.01). The detectability of these tumors with dynamic MRI was significantly superior to that with dynamic spiral CT using an injection rate of 2 ml/s (p < 0.01), but not significantly different from that of dynamic spiral CT using a rate of 3 ml/s. CONCLUSION: Dynamic MRI and dynamic spiral CT are comparable for detecting hypervascular intrahepatic metastases of HCC.

Adult↗
PubMedDate not supplied

Diameters of the pulmonary arteries and veins as an indicator of bilateral and unilateral pulmonary blood flow in patients with congenital heart disease.

OBJECTIVES: This study was done to clarify which diameter, that of the pulmonary arteries (PAs) or that of the pulmonary veins (PVs), more precisely reflects pulmonary blood flow (PBF) bilaterally and unilaterally. METHODS: To evaluate bilateral PBF, we studied 15 consecutive patients with Kawasaki disease as normal patients and 30 patients with tetralogy of Fallot who received cardiac catheterization. To evaluate unilateral PBF, 20 patients with various congenital heart diseases undergoing cineangiography and lung perfusion scintigraphy were studied. The diameter of PA was measured immediately proximal to the origin of the first lobar branches bilaterally, and right PA area, left PA area, PA area (mm2), and PA index (mm2/m2) were calculated. The diameter of PV was also measured distal to the junction with the left atrium. Right PV area, left PV area, PV area (mm2), and PV index (mm2/m2) were calculated from these diameters. Pulmonary blood flow (PBF) was obtained by the Fick method during catheterization. To evaluate unilateral PBF, PBF was divided into right and left PBF according to the right/left perfusion ratio measured by lung perfusion scintigraphy. RESULTS: Evaluation of bilateral PBF was as follows: in normal patients, PA and PV areas were correlated with body surface area (r = 0.88, p = 0.0001 and r = 0.93, p = 0.0001); PA index and PV index ranged from 248 to 436 (mean = 343) mm2/m2 and from 346 to 595 (mean = 466) mm2/m2, respectively, and were constant irrespective of body surface area; PA and PV areas were correlated with PBF in normal patients, as well as in patients with tetralogy of Fallot. There was a better correlation between PV area and PBF than between PA area and PBF in normal patients, as well as a significantly better correlation in patients with tetralogy of Fallot. Evaluation of unilateral PBF was as follows: right PV area was correlated with right PBF (p = 0.0002), while right PA area was not; left PV area and left PA area were correlated with left PBF; right/left PV area ratio was correlated with the right/left perfusion ratio with better agreement than right/left PA area ratio. CONCLUSION: Our data suggest that the size of PVs in patients with congenital heart disease may be more useful than the size of PAs to indicate bilateral and unilateral PBF than the size of PAs. Differences in PV area of each lung may be a suitable indicator of discrepancy in blood flow to each lung.

Cardiac Catheterization↗