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Biomedical subjects

H Sano

Publications and source records attributed to H Sano.

At least 397 records · Page 22Linked to original sources
PubMed1995

[Changes in hearing features according to days from onset of sudden deafness].

We analyzed 746 patients with idiopathic sudden hearing loss who visited our clinic within 16 days after the onset. Patients were divided into 10 groups according to the number of days between the initial visit and the onset. Initial hearing levels, audiometric types and hearing recoveries were investigated in these groups to estimate the natural history of sudden deafness. The results were as follows: 1) There were no significant differences among the 10 groups regarding the averaged five-frequency hearing levels of initial audiograms. 2) Regarding the audiometric types of the initial audiograms, flat and upward slope types were frequently seen in the groups who visited us within 6 days. In contrast, the population of down slope types gradually increased in the groups presenting after 7 days. In the ultimate audiograms, flat and down slope types were frequently seen in all groups. 3) There were significant differences among the 10 groups regarding the averaged five-frequency improvement (one-way analysis of variance, p < 0.01). After 9 days, hearing recovery became less likely.

Hearing↗
PubMed1995

[Endoscopic mucosal resection of the stomach using a ligating device (EMRL)--experimental study for the purpose of establishing reliable and safe technique].

We confirmed a new reliable and safe technique for endoscopic mucosal resection of the stomach using a ligating device (EMRL), which was used for endoscopic ligation of esophageal varices. We resected the gastric mucosa by this procedure in 6 mongrel dogs, and examined resected specimens histopathologically. It is concluded that EMRL can take a mucosal specimen 15 x 12mm in size on the average, be performed almost all the site which was previously difficult to resect endoscopically, and the submucosal local injection of physiological saline solution is necessary to perform EMRL. Based on these conclusion, we experimented to establish the safe and reliable technique of the divided mucosal resection, too. EMRL procedure is an easy and valuable treatment modality.

Adenoma↗
PubMed1995

[Clinical usefulness of 3-D CT endoscopic imaging of cerebral aneurysms].

Usefulness of endoscopic imaging of cerebral aneurysms is presented. 3D-luminal images were obtained using a new processing technique which extracts CT numbers in the boundary region between the vessel wall and contrast media filling in the vascular lumen. Clinical application of this technique to complicated large cerebral aneurysms showed that, with this 3D-CT endoscopic images and MRA, anatomical details of cerebral aneurysms such as the orifice of the aneurysm, intraluminal thrombus, and calcification of the wall could be clearly demonstrated. We operated on two large, complicated aneurysms after obtaining 3D-CT endoscopy images of the aneurysms. Such information was found to be very useful when operating on difficult and complicated cerebral aneurysms.

Artifacts↗
PubMed1995

[Evaluation of nuclear morphometric risk grade as a prognostic factor of early breast cancer].

The prognostic significance of nuclear areas was studied in 241 patients with primary stage I or II breast cancer. The mean follow-up period was 56.4 months. The nuclear areas of 100 breast cancer cells in HE stained specimen in each patient were measured by means of an image analyzing system, and the mean nuclear area (MNA) and standard deviation of nuclear area (SDNA) were calculated. MNA and SDNA were significantly larger in patients with recurrence than without it. Patients were divided into 2 groups according to the Nuclear Morphometric Risk Grade (NMRG), which was defined as follows: high risk: MNA > or = 80 microns 2 and SDNA > or = 28 microns 2; low risk: MNA < 80 microns 2 or SDNA < 28 microns 2. High risk patients revealed significantly poor disease free and overall survival than low risk patients (p < 0.0001, p < 0.0001). Furthermore, NMRG was a significant prognostic factor in node-negative patients. Cox multivariate analysis showed that nodal status and NMRG were independent predictors of tumor recurrence (n:p = 0.001; NMRG:p = 0.27) and survival (n:p < 0.001; in the NMRG:p = 0.0007). NMRG was a strong prognostic factor in patients in the early stage and it might support the decision for or against adjuvant therapy.

Breast Neoplasms↗
PubMed1995

[Respiratory function in students who had asthma in childhood].

Students who had asthma in childhood can be divided into three groups: "asthma-remission" group "asthma-relapsing" group and "non-asthma-remission" group. When we made inquiries about three different groups, the incidence of each group was 58%, 27% and 15%, respectively. In order to determine if childhood asthma affects respiratory function in adulthood, we measured respiratory functions by spirometry in 26 students who had asthma in childhood, and in seven control students. There was no significant difference between students with childhood asthma and control students in terms of FEV1.0% of predicted value. However, students who had asthma in childhood had lower levels of V25/HT% of predicted value in comparison with control students. The effects of deep inhalation in the three groups were evaluated by determining the values of maximal expiratory flow at 40% (MEF40) of vital capacity from partial (P) and maximal (M) flow-volume curves. There was no difference between the remission group and the control group in the MEF40 M/P ratio. This suggests that childhood asthma may deteriorate respiratory functions in adulthood by remodeling of peripheral airways.

Adult↗
PubMed1995

Spatial ventricular gradient in patients with Wolff-Parkinson-White syndrome in comparison with normal subjects: vectorcardiographic evidence for significant repolarization changes due to preexcitation.

We investigated the use of the spatial ventricular gradient (VG) from vectorcardiogram (VCG) to determine whether significant repolarization differences were present in patients with WPW syndrome compared with normal subjects and also examined which VG parameter (i.e., elevation, azimuth, and magnitude) reflected the differences in repolarization properties during preexcitation. VG was calculated in 49 patients of Wolff-Parkinson-White (WPW) syndrome (group A: left-sided accessory pathway, n = 29; group B: right-sided, n = 20). Group N consisted of 607 normal subjects. In group A, the azimuth of VG was significantly (p < 0.01) greater than in groups B and N. In group B, the elevation of VG was significantly (p < 0.01) greater than in groups A and N. There were no significant differences in the magnitude of VG among groups. QRS duration was significantly (p < 0.01) related with the elevation of VG in group B. These findings suggested that VG is useful for spatial evaluation of repolarization abnormalities during preexcitation, which are related to the site of the accessory pathway.

Adolescent↗
PubMed1995

[Three patients with spontaneous pneumomediastinum, including one in whom pneumomediastinum recurred].

We encountered three patients with spontaneous pneumomediastinum. All three (two men and one woman) were previously healthy. They complained of chest pain or dyspnea. On admission, physical examination revealed subcutaneous emphysema. Chest roentgenograms and computed tomograms revealed pneumomediastinum and subcutaneous emphysema. All other findings were normal. All patients were treated with bed rest and all recovered in 7 to 9 days. Pneumomediastinum recurred in one patient after 20 months.

Adolescent↗
PubMed1995

Interfacial morphology and strength of bonds made to superficial versus deep dentin.

PURPOSE: To evaluate the interfacial morphology (SEM) of two bonding systems to superficial and deep dentin using a reverse-sandwich technique, coupled with measurement of micro-tensile bond strengths (MTBS). MATERIALS AND METHODDS: Superficial and deep dentin disks were prepared from the same tooth in freshly-extracted human third molars. All-Bond 2 (total etch versus no etch) or Imperva Bond (total etch versus no etch) were applied to superficial versus deep dentin surfaces and the two disks were bonded together into a reverse-sandwich configuration. RESULTS: SEM revealed that All-Bond 2 and Imperva Bond applied under total etch conditions formed thicker resin-infiltrated layers (4-8 micrometers) on deep dentin than on superficial dentin (2-4 micrometers), and that All-Bond 2 and Imperva Bond applied to unetched dentin formed very thin resin-infiltrated layers (less than 0.5 micrometers) on both dentin substrates. MTBS of All-Bond 2 and Imperva Bond were more than 20 MPa irrespective of dentin depth and were not significantly different. Without acid etching, the MTBS of both systems to deep dentin was significantly lower than to superficial dentin. These results suggested that for the total-etch systems, dentin depth affected the thickness of the resin-infiltrated layer, but the thickness of the resin-infiltrated layer had no significant relationship with MBTS. The present data also indicated that the acid-etch technique could prevent the decrease of bond strength seen in deep dentin in the absence of etching.

Acid Etching, Dental↗
PubMed1995

Treatment and prognosis of a vertically fractured maxillary molar with widely separated segments: a case report.

This is a report of the treatment and prognosis of a maxillary second molar exhibiting a complete vertical crown-root fracture. The buccal and palatal segments were widely separated by as much as 2 mm and were immobile. To restore this tooth, it was essential to bring the segments into close apposition. This was accomplished by application of orthodontic elastics to the tooth crown in combination with a wire splint. After approximately 1 month of continuous use of the orthodontic elastics, the dislodged segments were suitably repositioned close to their original positions. The tooth was then endodontically treated and restored with a cast complete crown. The restored tooth has been functioning well, with periodic periodontal maintenance, for more than 3.5 years, indicating a promising prognosis.

Adult↗
PubMed1994

Expression of the gene for a small GTP binding protein in transgenic tobacco elevates endogenous cytokinin levels, abnormally induces salicylic acid in response to wounding, and increases resistance to tobacco mosaic virus infection.

Tobacco plants transformed with rgp1, a gene encoding a Ras-related small GTP binding protein, were previously shown to exhibit a distinct reduction in apical dominance with increased tillering. These abnormal pheno-types were later found to be associated with elevated levels of endogenous cytokinins (zeatin and zeatin riboside). Analysis of the expression of several genes known to be affected by cytokinins identified a clear increase in the mRNA levels of genes encoding acidic pathogenesis-related proteins in both transgenic plants and their progenies. This increase was directly attributable to elevated levels of the acidic pathogenesis-related protein inducers, salicylic acid (SA) and salicylic acid beta-glucoside, due to an abnormal and sensitive response of the transgenic plants to wounding. In contrast, mRNA levels of the gene for proteinase inhibitor II, which is normally induced by wounding, were generally suppressed in the same wounded plants, probably due to SA overproduction. The changes in SA and pathogenesis-related protein levels in the transgenic plants resulted in a distinct increase in their resistance to tobacco mosaic virus infection. In normal plants, the wound and pathogen-induced signal transduction pathways are considered to function independently. However, the wound induction of SA in the transgenic plants suggests that overexpression of this small GTP binding protein somehow interferes with the normal signal pathways, possibly by affecting cytokinin biosynthesis, and results in cross-signaling between these two transduction systems.

Journal Article↗
PubMed1994

[Detectability of cerebral aneurysms and surrounding vessels by three-dimensional evaluation using helical scanning CT (HES-CT)].

Helical scanning CT (HES-CT) is a new technique to enable high-speed volumetric data acquisition. We have applied HES-CT to the diagnosis of cerebral vascular diseases. In our experience, the relationship between the scanning parameters of HES-CT and image quality was complex and reciprocal, so that optimization of the parameters according to the clinical demands was essential. We compared HES-CT with conventional cerebral angiography to determine the detectability of the aneurysm and surrounding vessels, and sought the optimal parameters to delineate small vessels. All aneurysms were detected in multiplanar reconstruction (MPR) images. The smallest one was 3 x 4 mm. MPR images were found to have some advantages over conventional cerebral angiography in delineation of intracranial aneurysms: 1) scanning was over in a short time (30s), 2) the relationship between the aneurysm and surrounding vessels was easily recognized, 3) the diameter of the neck could be measured, because the neck of the aneurysm and parent artery could be imaged on the same plane without overlapping another vessel, 4) calcified lesions on the aneurysmal wall were detected, and 5) HES-CT was done safety without arterial puncture. However, the detectability of unknown aneurysm was less than the detectability of known aneurysm in MPR images. The 180 degrees interpolation algorithm and 1 mm slice were effective in detecting small vessels. However, vessels with a diameter less than 1 mm could not be detected by HES-CT. HES-CT was considered to be useful as a supplementary examination to conventional angiography for the diagnosis of intracranial aneurysms.

Adolescent↗
PubMed1994

Role of vascular cell adhesion molecule 1/very late activation antigen 4 and intercellular adhesion molecule 1/lymphocyte function-associated antigen 1 interactions in antigen-induced eosinophil and T cell recruitment into the tissue.

To determine the role of vascular cell adhesion molecule 1 (VCAM-1)/very late activation antigen 4 (VLA-4) and intercellular adhesion molecule 1 (ICAM-1)/lymphocyte function-associated antigen 1 (LFA-1) interactions in causing antigen-induced eosinophil and T cell recruitment into the tissue, we studied the effect of the in vivo blocking of VCAM-1, ICAM-1, VLA-4, and LFA-1 by pretreatment with monoclonal antibodies (mAb) to these four adhesion molecules on the eosinophil and T cell infiltration of the trachea induced by antigen inhalation in mice. The in vivo blocking of VCAM-1 and VLA-4, but not of ICAM-1 and LFA-1, prevented antigen-induced eosinophil infiltration into the mouse trachea. On the contrary, the in vivo blocking of VCAM-1 and VLA-4, but not of ICAM-1 and LFA-1, increased blood eosinophil counts after antigen challenge, but did not affect blood eosinophil counts without antigen challenge in sensitized mice. Furthermore, the expression of VCAM-1 but not ICAM-1 was strongly induced on the endothelium of the trachea after antigen challenge. In addition, pretreatment with anti-IL-4 mAb decreased the antigen-induced VCAM-1 expression only by 27% and had no significant effect on antigen-induced eosinophil infiltration into the trachea. The in vivo blocking of VCAM-1 and VLA-4 inhibited antigen-induced CD4+ and CD8+ T cell infiltration into the trachea more potently than that of ICAM-1 and LFA-1. In contrast, regardless of antigen challenge, the in vivo blocking of LFA-1, but not of ICAM-1, increased blood lymphocyte counts more than that of VCAM-1 and VLA-4. These results indicate that VCAM-1/VLA-4 interaction plays a predominant role in controlling antigen-induced eosinophil and T cell recruitment into the tissue and that the induction of VCAM-1 expression on the endothelium at the site of allergic inflammation regulates this eosinophil and T cell recruitment.

Administration, Inhalation↗
PubMed1994

Light and nutritional regulation of transcripts encoding a wheat protein kinase homolog is mediated by cytokinins.

Many metabolic processes in plants are regulated by phosphorylation of proteins by kinases, but little is known of the roles that specific protein kinase play in the various signal transduction pathways or the mechanisms by which these kinases themselves are regulated. We report here the isolation of a gene, wpk4, encoding a putative protein kinase from wheat that appears to belong to the SNF1 kinase subfamily and that shows increased transcript levels in response to multiple stimuli: light, nutrient deprivation, and cytokinin application. Although wpk4 mRNA is undetectable in etiolated seedlings, it rapidly accumulates within 1 hr of illumination. General nutrient deprivation also increases wpk4 mRNA levels, but only under light conditions. In addition, of the various phytohormones tested, cytokinin (N6-benzylaminopurine) specifically increases wpk4 mRNA levels regardless of the light conditions, whereas in the presence of a cytokinin antagonist the level of wpk4 mRNA is not increased by either light or nutrient deprivation. These results suggest that the light and nutrient signals that induce wpk4 mRNA accumulation may be mediated through cytokinins and provide a strong basis for examining the coordinated regulation of protein phosphorylation by light, cytokinins, and nutritional cues in a single transduction pathway.

Adenine↗
PubMed1994

Different effect of thymidine kinase loss on TTP pools; comparison among human leukemia cell lines.

Thymidine kinase (TK)-deficient cells were established from six human leukemia cell lines to evaluate the role of TK in maintaining intracellular TTP pools. The residual TK activities in mutant cells were less than 3% of those of wild-type strains, except for a B-lymphoid cell line, Ball-1 (8.7%). In a promyelocytic leukemia cell line (HL-60), a splenic B cell line (WI-L2) and Ball-1, a mutational loss of TK resulted in a decrease of TTP pools by 80%, 33% and 54%, respectively. On the other hand, in the T cell lines, Molt-3, Molt-4 and CEM, TTP did not show any significant differences between parent and TK-deficient cells. TK-deficient HL-60 cells had, however, comparable levels of dATP, dGTP and dCTP with wild-type cells. An analysis of growth characteristics showed that the decrease of TTP was not due to the change of the cell cycle distribution. These results indicate that TK plays a different role in maintaining TTP pools among human leukemia cell lines.

B-Lymphocytes↗
PubMed1994

Microdynamics of the phospholipid bilayer in cardiomyopathic hamster heart cell membrane.

To investigate the microdynamics and the structural architecture of the membrane phospholipid bilayer during the course of cardiomyopathy, membrane fractions were prepared from hearts of cardiomyopathic Syrian hamsters (BIO 14.6) aged 4, 18 and 31 weeks and compared with age-matched control hamsters (F1b). Membrane cholesterol, phospholipids and phospholipid fatty acids were measured by thin-layer chromatography, gas-liquid chromatography and high performance liquid chromatography. Microdynamics of the phospholipid bilayer were determined by a nanosecond fluorometer using pulsed excitation of a fluorescent probe, diphenyl-hexatriene. At the age of 4 weeks, there was no difference in lipid compositions and microdynamics between the BIO 14.6 and F1b. At the age of 18 weeks, saturated fatty acids, 18:0 and 22:0 increased and 20:0, 20:2 and 32:4 decreased in the BIO 14.6. At the age of 31 weeks, adding to the above changes in phospholipid fatty acids, unsaturated fatty acids 20:4 and 22:6 decreased, moreover membrane phospholipids, especially phosphatidylinositol and phosphatidylethanolamine significantly decreased. The viscosity and the wobbling angle of phospholipid molecules were decreased significantly. We have previously demonstrated that intracellular Ca2+ accumulation might be responsible for the pathogenesis of cardiomyopathy. Thus, we conclude that cardiomyopathic membrane may alter its structure and function with age. These alterations in cell membranes might be involved in the cardiac hypertrophy and dysfunction through impaired Ca2+ handling in cardiomyopathic hamsters.

Animals↗
PubMed1994

Transforming growth factor beta-1 modulates the number of beta-adrenergic receptors in cardiac fibroblasts.

The effects of transforming growth factor beta-1 on concentration of intracellular Ca2+ changes in the presence of isoproterenol were studied in cardiac fibroblasts. Transforming growth factor beta-1 effect on cyclic-AMP production and ligand assay of beta-adrenergic receptors were also examined. Production of cyclic-AMP in fibroblasts preincubated with transforming growth factor beta-1 decreased compared with non-transforming growth factor beta-1-treated fibroblasts in the presence of isoproterenol. An increase of intracellular Ca2+ concentration in the presence of isoproterenol was also inhibited in transforming growth factor beta-1-treated fibroblasts. Islet-activating protein did not restore these reactions of transforming growth factor beta-1. Concentration change of intracellular calcium under the treatment of transforming growth factor beta-1 was unaffected by forskolin addition. Binding of [3H]CGP-12177 was decreased to 47% of control preincubated for 24 h with transforming growth factor beta-1 in fibroblasts. Scatchard plots suggested a decrease in beta-adrenergic receptor number without specific change in receptor affinity. These results suggested that transforming growth factor beta-1 modulates the signal transduction through beta-adrenergic receptor and intracellular Ca2+ concentration by regulating the number of receptor in fibroblasts.

Animals↗
PubMed1994

Enzymic synthesis of the trisaccharide core region of the carbohydrate chain of N-glycoprotein.

Transmannosylation from mannotriose (Man beta 1-4Man beta 1-4Man) to the 4-position at the nonreducing end N-acetylglucosaminyl residue of N,N'-diacetylchitobiose was regioselectively induced through the use of beta-D-mannanase from Aspergillus niger. The enzyme formed the trisaccharide Man beta 1-4GlcNAc beta 1-4GlcNAc (3.7% of the enzyme-catalysed net decrease of N,N'-diacetylchitobiose) from mannotriose as a donor and N,N'-diacetylchitobiose as an acceptor. Mannobiose (Man beta 1-4Man) was also shown to be useful as a donor substrate for the desired trisaccharide synthesis.

Aspergillus niger↗