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Biomedical subjects

K Abe

Publications and source records attributed to K Abe.

At least 919 records · Page 51Linked to original sources

Isolation of genes involved in gravitropism.

When upright growing wild type barley seedling are placed to a horizontal position they will respond to this gravistimulation by a curvature against the gravitational force. The mutant serpentina, however, shows gravitropic response only in an early stage of development. Older seedlings, gravistimulated 92 h after germination are agravitropic. They will grow horizontally. We try to identify genes involved in gravitropism by comparing gene expression of i) non-gravistimulated and gravistimulated wild type barley seedlings and of ii) gravistimulated wild type and serpentina.

DNA Probes↗

Immunoreactive adrenomedullin in human adrenal glands and adrenal tumors.

Adrenomedullin is a potent vasodilator peptide that was isolated from human pheochromocytoma. We developed a sensitive and specific radioimmunoassay for adrenomedullin and studied the presence of adrenomedullin in human adrenal glands and adrenal tumors, including pheochromocytoma. High concentrations of immunoreactive adrenomedullin were found in normal parts of adrenal glands (cortex and medulla) (12.6 +/- 1.0 pmol/g wet wt, N = 7, mean +/- SEM). High concentrations of immunoreactive adrenomedullin were also present in the tumor tissues of pheochromocytoma (4.5 +/- 1.5 pmol/g wet wt, N = 11). Immunoreactive adrenomedullin was detected in some adrenocortical tumors, but these concentrations were much lower than those in the normal adrenal glands and pheochromocytomas. Reverse phase high-performance liquid chromatography of the normal adrenal gland and pheochromocytoma showed a peak eluting in the position of synthetic adrenomedullin 1-52. The present study has shown the presence of high concentrations of immunoreactive adrenomedullin in the normal adrenal glands and pheochromocytomas.

Adenocarcinoma↗

[Clinical features of acute hepatitis G].

Fifty-one patients with acute A, B, C, and non A-C hepatitis were studied. Alcoholic abusers and drug-induced hepatitis were excluded from non A-C hepatitis. Among 10 patients with acute non A-C hepatitis, 3 were positive for HGV-RNA by nested RT-PCR as primer of 5' non-coding region of HGV. Maximal s-ALT values in acute hepatitis G patients were significantly higher than those in acute hepatitis C(p < 0.05), but not different from those in acute hepatitis A and B. Although HGV-RNA was demonstrated after 9 years of onset of hepatitis in one patient, non of three patients took chronic course. In one patient, route of transmission was assumed to be blood transfusion.

Acute Disease↗

In situ observation of bovine serum albumin-adsorbed stearic acid monolayer by Brewster angle microscopy.

The morphology of protein-adsorbed stearic acid monolayers containing a fluorescent probe (rhodamine B octadecylester perchloride: RBO) was observed by using fluorescence spectroscopy, fluorescence microscopy, and Brewster angle microscopy (BAM). The quenching of fluorescence of RBO was observed at the limiting area of the stearic acid monolayer. Thus, the fluorescence of RBO could be a good marker for packing of the matrix monolayer. On the other hand, the BAM image showed the morphology of not the matrix monolayer, but the adsorbed protein monolayer. Thus, the packing processes of the two could be distinguished. The present method is available for a protein that does not have visible absorption, such as bovine serum albumin (BSA). It is suggested that electrostatic interaction between matrix and protein molecules greatly affects the change in the morphology of the protein-adsorbed monolayer.

Adsorption↗

Structural changes of collagen components and diminution of nerves in congenital ureteropelvic junction obstruction.

PURPOSE: Three-dimensional arrangements of smooth muscle cells, collagenous component and peripheral nerves of congenital ureteropelvic junction (UPJ) obstruction were studied in order to clarify the pathogenetic mechanism of interaction among these neuro-myo-stromal components. MATERIALS AND METHODS: The UPJ and upper ureters were obtained from 14 patients with congenital hydronephrosis (7 intrinsic and 4 extrinsic obstruction) and 7 normal controls. Three-dimensional arrangement of each structural component was observed by scanning electron microscopy, and the nerve distribution was analyzed with immunohistochemistry for protein gene product 9.5. RESULTS: The UPJ of intrinsic obstruction had structural features as follows. Muscle fascicles were sparse and thin. Each muscle cell was thin in diameter. Intercellular spaces were six to seven times wider than controls. Collagen fibrillar sheaths of smooth muscle cells (pericellular collagen fibrils attached to the basement membrane) were interwoven to form a dense felt-like structure against thin lace-like sheaths in controls. Interstitial collagenous component showed dense and compact structure against loose network of wavy collagen bundles in controls. In the muscular layer, nerve distribution was decreased to about one-third of controls. In contrast, non-stenotic portion of intrinsic UPJ obstruction as well as materials from extrinsic UPJ obstruction showed no structural difference as compared with controls. CONCLUSIONS: In the intrinsic obstruction, nerve fibers were depleted in the muscular layers in the ureteric walls, resulting in dysfunction and atrophy of muscle fibers and an increase of collagen fibers in the muscle layers with abnormal accumulation of intercellular and interstitial collagen. These changes may disrupt the mobility of UPJ and lead to both mechanical and functional obstruction.

Adult↗

[Age-related changes of diffusional anisotropy in the cerebral white matter in normal subjects].

To investigate age-related changes of diffusional anisotropy in the cerebral white matter, we performed diffusion-weighted MRI studies in 21 normal subjects aged 25 to 96 years. The anisotropic rations (ARs), defined as the apparent diffusion coefficients perpendicular to the nerve fibers to those parallel to the nerve fibers, were significantly higher in elderly than in young subjects in the anterior and posterior white matter surrounding the lateral ventricle. Moreover, significant correlation between age and AR was found in the anterior white matter. The ventricular index (VI) measured on MRI, as a quantitative indicator of brain atrophy, was significantly higher in elderly than younger subjects, and significantly correlated with AR in the anterior white matter. Multiple regression analysis demonstrated that the VI showed the highest correlation for AR. On the other hand, there was no significant correlations between ARs in the corpus callosum and age. These results suggest that morphological changes in the myelin and axon in the white matter occur in elderly normal subjects, probably due to neuronal loss with aging.

Adult↗

Proposal of reference values for home blood pressure measurement: prognostic criteria based on a prospective observation of the general population in Ohasama, Japan.

The purpose of this study was to propose reference values, from a viewpoint of prognostic significance, for blood pressure (BP) measured at home with a semiautomated device (home BP measurement) to differentiate normotension and hypertension. We obtained home BP measurements for 1,913 population-based subjects aged 40 years and over in a rural Japanese community and followed up their survival for a mean duration of 5.0 years. There were 141 deaths during the follow-up period. The association between baseline BP values and the overall mortality was examined by Cox proportional hazards regression model, adjusted for age, gender, and the use of antihypertensive medication. The results indicated that the predictive power of home BP level for subsequent mortality was stronger than that of casual screening BP. There was a linear association between home systolic BP and mortality. The association between home diastolic BP and mortality was nonlinear and well approximated with the secondary degree equation of diastolic BP values. Based on this relation, we propose that the reference value for hypertension is 137/84 mm Hg, and normotension is below 137 mm Hg for home systolic BP and between 66 and 83 mm Hg for home diastolic BP. Home diastolic BP below 66 mm Hg should be considered as low diastolic blood pressure. In this population, home systolic BP of 137 mm Hg and home diastolic BP of 84 mm Hg corresponded to the 80th and 87th percentiles, respectively. Then, 29% of the subjects were classified as having hypertension, 52% as normotension, and 19% as low diastolic blood pressure. All previous studies proposing reference values for home BP measurement, derived from cross-sectional observations, were based on the statistical distribution of home BP values. The reference value must, however, be the one that best predicts the risk for morbidity and mortality from hypertension-related complications. This is the first report proposing reference values for home BP measurement based on prognostic criteria.

Adult↗

[Experiment in ultra-rapid injection of isotonic sodium chloride after injection of contrast medium: time-density analysis of the aorta and portal vein].

Ultra rapid injection of isotonic sodium chloride after the injection of contrast medium may make it possible to clearly distinguish between the arterial phase and the portal phase. This method could improve the detectability of hepatocellular carcinoma on double phase dynamic spiral CT. A time-density analysis of the aorta and the portal vein was carried out according to the following 2 protocols (5 cases each). In protocol 1, 95 ml of Iopamidol (300 mgI/ml) was injected at a rate of 3 ml/second, while the protocol 2, 40 ml of isotonic sodium chloride was injected at a rate of 10 ml/second after the injection of 60 ml of Iopamidol (300 mgI/ ml) at a rate of 10 ml/second. The duration of the arterial phase (aortic enhancement unit (EU) > or = 200) in protocol 2 was 11 seconds, which was shorter than that in protocol 1. In protocol 2, the duration of the clearly portal dominant phase (reversal phase; aortic EU < portal EU) was about 11 seconds.

Adult↗

[beta-blocker in hypertension].

The beta-blockers are either nonselective and affect both beta 1- and beta 2-receptors, are relatively selective for the alpha 1 subclass, or are able to have activity against alpha-receptors. The ability to reduce blood pressure is very common among all beta-blockers, and beta-blockers are recommended for one of the first-line drugs in hypertension treatment by JNCV. beta-blockers should be used considering their pharmacological properties and potential side effects, according to the pathophysiological conditions involved. The superiority of beta-blocker to other types of antihypertensive drug has not yet been evidenced by larger scale clinical trials which have been carried out so far. To verify more precisely the usefulness of beta-blocker in hypertension treatment, more large scale clinical trials are required to be carried out. The fixed-dose combination of beta-blockers and calcium blockers appears to be more effective rather than that of beta-blockers and diuretics.

Adrenergic beta-Antagonists↗

[Salivary gland masses: dynamic MR imaging and pathologic correlation].

PURPOSE: To evaluate the efficiency of dynamic contrast-enhanced magnetic resonance imaging (MRI) for the diagnosis of salivary gland masses. MATERIALS AND METHODS: We retrospectively examined 19 salivary gland masses that were pathologically diagnosed by surgical operation or biopsy. We obtained T1- and T2-weighted images on MRI, performed dynamic studies on each mass and examined the correlation between enhancement patterns and pathological findings. RESULTS: Four enhancement patterns were recognized on contrast-enhanced MRI: type 1 showed marked, homogeneous enhancement; type 2 slight, homogeneous enhancement; type 3 marginal enhancement; and type 4 poor enhancement of the mass. Most pleomorphic adenomas had a type 1 enhancement pattern, but two had a type 2 pattern. Pathologically, each mass enhancement pattern had different tumor cell and matrix components. Warthin's tumor generally showed the type 4 pattern. Primary malignant tumors of the salivary gland all showed the type 3 pattern, and pathological specimens showed many tumor cells along the marginal portion of the tumor. One inflammatory cyst and one Warthin's tumor also showed the type 3 pattern. Except for metastatic renal cell carcinoma, the enhancement patterns of late phase images and dynamic study images were the same. CONCLUSIONS: Dynamic MRI added little diagnostic information about salivary gland masses, but the contrast-enhanced MR features correlated well with the pathological findings.

Adenolymphoma↗