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Biomedical subjects

T Ono

Publications and source records attributed to T Ono.

At least 379 records · Page 21Linked to original sources
PubMed1998

Benign asbestos pleural effusion associated with pulmonary aspergilloma.

A rare case of benign asbestos pleural effusion associated with aspergilloma is reported. A chest radiograph of a 75-year-old Japanese man who was admitted with right chest pain showed a right pleural effusion and nodular shadows in the right apex and left middle lung field. Thoracocentesis revealed an exudate with atypical mesothelial cells. An open lung biopsy showed aspergilloma in the right S2 area and no evidence of malignancy. Many reactive mesothelial cells were found in the pleura. A quantitative asbestos digestion study of the lung tissue biopsy showed high-grade asbestos exposure.

Aged↗
PubMed1998

Hereditary perioral pigmented follicular atrophoderma associated with milia and epidermoid cysts.

Eight members of a single family all presented the characteristic changes of facial, especially perioral, pigmented follicular atrophoderma, with numerous milia and epidermoid cysts. For this condition. diagnosis at a glance may be possible because of the perioral cutaneous manifestations. Histopathological examination of follicular atrophoderma revealed proliferation of basaloid cells continuous with the epidermis and coarse collagen fibres, with a decreased density of elastic fibres around the basaloid cells. Two of the eight individuals also showed generalized hypohidrosis. The eight affected persons were the proband, her son, mother, uncle, two younger sisters, cousin and nephew: an autosomal dominant mode of transmission was suggested from this family tree. The patients' symptoms resembled those of Bazex-Dupré-Christol syndrome, except for the different distribution of the follicular atrophoderma and the absence of basal cell carcinoma and hypotrichosis. This disease may be an entirely new syndrome characterized by perioral pigmented follicular atrophoderma associated with milia and epidermoid cysts.

Adolescent↗
PubMed1998

[Partial median sternotomy for pediatric cardiac surgery].

In order to minimize scarring and thereby improve the postoperative cosmetic appearance of pediatric cardiac surgery patients, we perform partial median sternotomy incisions. A short midline skin incision, from 1 to 2 cm below the articular notch of the second rib to the xiphoid process, is made. The sternum was divided from the xiphoid process to the articular notch of the second rib. The thymus is mobilized and the pericardium incised longitudinally. The aorta and superior and inferior vena cava are mobilized to facilitate direct cannulation. Cardiopulmonary bypass is instituted in the usual fashion. Twenty-four pediatric patients underwent repair of cardiac anomalies through a partial median sternotomy incision at our institution between June 1997 and September 1998. The average age of the patients was 4 years and 4 months (range, 4 days to 12 years) and the average weight was 16.0 kg (range, 3.2 to 40.5 kg). Cases included 13 VSD (ventricular septal defect) [including one DCRV (double chambered right ventricle) and one PS (pulmonary stenosis)], 9 ASD (atrial septal defect), one ECD (endocardial cushion defect), and one DORV (double outlet right ventricle) with mitral atresia. All patients were extubated within 3 hours after surgery and the average length of the ICU stay was within 24 hours (except for one 4-day-old baby who died of LOS (low cardiac output syndrome) on the 16th postoperative day). There were no wound infections or hospital mortalities. In our experience, this approach is safe, provides good exposure, and provides excellent cosmetic results.

Cardiac Surgical Procedures↗
PubMed1998

Morphologic changes in the upper airway structure following surgical correction of mandibular prognathism.

The purpose of this study was to investigate morphologic changes in oropharyngeal structures in mandibular prognathic patients after orthognathic surgery. The study consisted of 25 patients (12 males and 13 females) with mandibular prognathism who underwent surgical and orthodontic treatment. A set of 4 standardized lateral cephalograms were obtained from each subject preoperatively and at 3 months, 6 months, and 1 year postoperatively. Morphologic changes in upper airway structures were evaluated longitudinally by gender. Parameters of the anteroposterior width of the pharynx significantly decreased at 3 and 6 months in both genders, and these parameters tended to rebound to the preoperative values 1 year postoperatively in females, but not in males. The hyoid bone significantly descended inferiorly 1 year postoperatively in males, while there were no significant changes in females. The distance between the hyoid bone and the third vertebra gradually decreased in males postoperatively; however, there were no significant changes in females. The cross-sectional area of the hypopharynx significantly decreased 1 year postoperatively in males, but not in females. These results indicate that the upper airway morphology changed differently in males and females following surgery. To compensate for skeletal changes following surgery, it appears that males and females responded in different ways to preserve a functional upper airway.

Adult↗
PubMed1998

[Partial median sternotomy for pediatric cardiac surgery].

In order to minimize scar appearance and thereby improve postoperative cosmetic appearance for pediatric cardiac surgery patients, we performed partial median sternotomy incisions. A short midline incision, from 1 to 2 cm below the articular notch of the 2nd rib to the xiphoid process, was made. The sternum was divided from the xiphoid process to the articular notch of the 2nd rib. The thymus was mobilized and the pericardium incised longitudinally. The aorta and superior and inferior vena cava were mobilized to facilitate direct cannulations. Cardiopulmonary bypass was instituted in the usual fashion. From June to December 1997, 14 patients between the ages of 4 days and 12 years have undergone cardiac repair using this technique. Cases included 7 VSD (including 4 pulmonary hypertension and 1 DCRV), 5 ASD, 1 ECD and and 1 DORV with mitral atresia. All patients were extubated within 3 hours after surgery, and there were no wound infections or hospital mortalities (except one 4 day old baby who died by LOS on the 16th postoperative day). In our experience, this approach is safe and provides good exposure with excellent cosmetic results.

Cardiac Surgical Procedures↗
PubMed1998

Contribution of endothelium in contractile response of isolated rabbit aortic preparation to electrical field stimulation.

An isolated rabbit aortic preparation, on which drugs selectively act from the intimal surface was made. The contractile response of the aortic preparation to norepinephrine (NE) (1 nM-10 microM) administered from the intimal surface was considerably reduced by removal of the endothelium, whereas the response to KCl was not changed. The contractile response of the aortic preparation to electrical field stimulation (EFS) was abolished by the treatment with tetrodotoxin (1 microM), guanethidine (1 microM) or prazosin (10 microM), indicating that the response was elicited by the release of NE from the adrenergic nerve terminals. The contractile response of the aortic preparation to EFS was also considerably reduced by the removal of the endothelium. A nitric oxide (NO) synthase inhibitor, NG-nitro-L-arginine (100 microM) had almost no effect on the contractile response to EFS, indicating that the involvement of NO in the contractile response was negligible. In prostaglandin F2 alpha (PGF 2 alpha)-contracted aortic preparation, the contractile response to EFS was never converted into relaxing response by the treatment with prazosin (10 microM). The finding confirmed that adrenergic beta action of NE released from nerve terminals on the aorta was minor. These findings indicate that endogenously released NE from adrenergic nerve terminals as well as exogenously administered NE acts on the endothelium and may release endothelium derived contracting factor(s) which act together with NE on the vascular smooth muscle.

Animals↗
PubMed1998

[Late phase II study of YNK-01 (an oral prodrug of cytarabine) for hepatocellular carcinoma].

Twenty-three patients with hepatocellular carcinoma (HCC) were enrolled in this cooperative study conducted in Hirosaki University Hospital. They were treated with YNK-01, a prodrug of cytarabine for oral administration. YNK-01 was given for 2 weeks and repeated every 4 weeks for as long as possible. There were 13 patients with NC, 10 with PD, and no PR. Among NC cases, 5 patients were maintained with NC for longer than 6 months. The main side effects of YNK-01 were anemia, leukopenia, thrombocytopenia, and symptoms of the alimentary tract (nausea, anorexia, diarrhea, etc), but no severe side effects over Grade 3 were observed.

Administration, Oral↗
PubMed1998

[Autonomic nervous function of the patients with neurally mediated syncope].

Although diagnosis of neurally mediated syncope (NMS) using head-up tilt (HUT) test has been established, the exact mechanism of NMS has not yet been elucidated. We evaluated beta and alpha-adrenergic function in NMS patients by pharmacological autonomic function test. The alpha-adrenergic sensitivity of NMS patients was significantly lower than that of control subjects. The patients who need low dose isoproterenol for provocation of syncope showed higher beta-adrenergic sensitivity than patients who developed syncope without isoproterenol. Thus, pharmacological autonomic function test was useful for evaluation of NMS patients.

Adolescent↗
PubMed1998

[On the application of the triple energy window method to the 201Tl imaging].

In the radionuclide imaging by 201Tl several K-X rays are acquired, so it is difficult to eliminate scattered photons in the acquired photons. This paper describes the limitation and efficiency of the triple energy window (TEW) method in the application of 201Tl myocardial studies. We evaluated the TEW method by simulations and the setting of the parameters in the TEW method were 20, 30 and 40% for the width of the main window, 3, 5 and 7% for the width of the two sub-windows. Moreover, the location of the main window was shifted by each 1 keV from 60 to 80 keV. Simulation results were evaluated with the mean square error between true scattered photons and estimated scattered photons. The results show that the mean square error was minimized when the widths of the main window were 20, 30 and 40%, and the centers of the main window were 66-68, 69-70 and 72-73 keV, respectively.

Algorithms↗
PubMed1997

A comparison of the genotoxicity of ethylnitrosourea and ethyl methanesulfonate in lacZ transgenic mice (Muta Mouse).

We compared the induction of gene mutations and chromosomal aberrations by ethylating agents in lacZ transgenic mice (Muta Mouse). Chromosomal aberrations were detected by the peripheral blood micronucleus assay. Gene mutations were detected in the lacZ transgene. A small amount of blood was sampled from a tail vessel during the expression time for fixation of gene mutations in vivo; this enabled us to detect and compare clastogenicity and gene mutations in the identical mouse. Single intraperitoneal injections of ENU (50-200 mg/kg) and EMS (100-400 mg/kg) strongly induced micronucleated reticulocytes (MN) detectable in peripheral blood 48 h after treatment. The maximum MN frequencies induced were 6.6% and 3.3% for ENU (100 mg/kg) and EMS (400 mg/kg), respectively (the control value was 0.3%). lacZ mutant frequency (MF) was analyzed in bone marrow and liver 7 days after treatment. Spontaneous MFs were 2.0-4.6 x 10(-6). MF in bone marrow was increased by ENU to 3.4 x 10(-5) at 200 mg/kg and induced by EMS to 1.8 x 10(-5) at 400 mg/kg. In liver, however, both chemicals at their highest doses induced only slight increases in MF. The induction of both micronuclei and lacZ mutations in bone marrow by both ENU and EMS correlated better with O6-ethylguanine adducts than with N7-ethylguanine adducts. The mutants (19 for ENU and 12 for EMS) were subjected to DNA sequence analysis. Among EMS-induced mutations, 75% were GC to AT transitions, which were probably caused by O6-ethylguanine. Among ENU-induced mutations, in contrast, 40% occurred as AT base pair substitutions (6 AT to TA transversions and 2 AT to GC transitions) (no such mutations were induced by EMS). These results, together with the known reactivity of ENU to thymine suggest that thymine adducts play a significant role in the ENU mutagenesis.

Animals↗
PubMed1997

2'-Fluoro modified nucleic acids: polymerase-directed synthesis, properties and stability to analysis by matrix-assisted laser desorption/ionization mass spectrometry.

Fragmentation is a major factor limiting mass range and resolution in the analysis of DNA by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Protonation of the nucleobase leads to base loss and backbone cleavage by a mechanism similar to the depurination reactions employed in the chemical degradation method of DNA sequencing. In a previous study [Tang,W., Zhu,L. and Smith,L.M. (1997) Anal. Chem ., 69, 302-312], the stabilizing effect of substituting the 24 hydrogen with an electronegative group such as hydroxyl or fluorine was investigated. These 24 substitutions stabilized the N-glycosidic linkage, blocking base loss and subsequent backbone cleavage. For such chemical modifications to be of practical significance, it would be useful to be able to employ the corresponding 24-modified nucleoside triphosphates in the polymerase-directed synthesis of DNA. This would provide an avenue to the preparation of 24-modified PCR fragments and dideoxy sequencing ladders stabilized for MALDI analysis. In this paper methods are described for the polymerase-directed synthesis of 24-fluoro modified DNA, using commercially available 24-fluoronucleoside triphosphates. The ability of a number of DNA and RNA polymerases to incorporate the 24-fluoro analogs was tested. Four thermostable DNA polymerases [Pfu (exo-), Vent (exo-), Deep Vent (exo-) and UlTma] were found that were able to incorporate 24-fluoronucleotides with reasonable efficiency. In order to perform Sanger sequencing reactions, the enzymes' ability to incorporate dideoxy terminators in conjunction with the 24-fluoronucleotides was evaluated. UlTma DNA polymerase was found to be the best of the enzymes tested for this purpose. MALDI analysis of enzymatically produced 24-fluoro modified DNA using the matrix 2,5-dihydroxy benzoic acid showed no base loss or backbone fragmentation, in contrast to the extensive fragmentation evident with unmodified DNA of the same sequence.

DNA↗
PubMed1997

Three-dimensional localization of dipoles for potentials evoked by posterior tibial nerve stimulation in the monkey.

Somatosensory evoked potentials (SEPs) elicited by right posterior tibial nerve stimulation were simultaneously recorded from 21-27 epidural electrodes in three monkeys. N23-P40 was recorded anterior to the left central sulcus, and P23-N40 was recorded on the parietal midline and the middle portion of the right hemisphere. These potentials were thought to be the primary cortical responses elicited by posterior tibial nerve stimulation in the monkey, since a topographical map made of them corresponded to the paradoxical lateralization of the primary cortical components in human posterior tibial nerve SEPs. Current source generators (dipoles) of these potentials were 3-dimensionally identified dipoles located in the left side of the mesial wall of the anterior parietal cortex, and oriented obliquely toward the right hemisphere by a dipole tracing (DT) method in which the 3-dimensional localization of dipoles in the brain were estimated and superimposed on magnetic resonance imaging (MRI) images.

Animals↗
PubMed1997

Calcium sensitization of smooth muscle mediated by a Rho-associated protein kinase in hypertension.

Abnormal smooth-muscle contractility may be a major cause of disease states such as hypertension, and a smooth-muscle relaxant that modulates this process would be useful therapeutically. Smooth-muscle contraction is regulated by the cytosolic Ca2+ concentration and by the Ca2+ sensitivity of myofilaments: the former activates myosin light-chain kinase and the latter is achieved partly by inhibition of myosin phosphatase. The small GTPase Rho and its target, Rho-associated kinase, participate in this latter mechanism in vitro, but their participation has not been demonstrated in intact muscles. Here we show that a pyridine derivative, Y-27632, selectively inhibits smooth-muscle contraction by inhibiting Ca2+ sensitization. We identified the Y-27632 target as a Rho-associated protein kinase, p160ROCK. Y-27632 consistently suppresses Rho-induced, p160ROCK-mediated formation of stress fibres in cultured cells and dramatically corrects hypertension in several hypertensive rat models. Our findings indicate that p160ROCK-mediated Ca2+ sensitization is involved in the pathophysiology of hypertension and suggest that compounds that inhibit this process might be useful therapeutically.

Amides↗
PubMed1997

Relationship between change of movement direction and activity of hippocampal place cells.

Hippocampal neurons which increase their activity when the rat passes through a certain position in the environment are called place cells. This paper describes the relationship between their temporal firing patterns and the behavior of the rat with the aim of characterizing the information they encode. The place field was identified in a circular open field during locomotion rewarded by intracranial self-stimulation of lateral hypothalamus. Detailed analysis of temporal firing patterns shows a correlation between changes in the orientation of movement trajectory and occurrence of the last firing of the burst trains emitted during passage of the animal through the place field. This suggests that some hippocampal neurons may encode the spatial information about the orientation changes in the place field.

Animals↗
PubMed1997

Biochemical and pharmacological characterization of FK706, a novel elastase inhibitor.

FK706, sodium 2-[4-[[(S)-1-[[(S)-2-[[(RS)-3, 3, 3-trifluoro-1-isopropyl-2-oxopropyl]aminocarbonyl]pyrrolidin -1-yl]carbonyl]-2-methylpropyl] aminocarbonyl] benzoylamino] acetate, C26H32F3N4NaO7, is a synthetic water-soluble inhibitor of human neutrophil elastase. This compound demonstrated a competitive and slow-binding inhibition of human neutrophil elastase with a Ki of 4.2 nM. In studies using synthetic substrates, FK706 inhibited human neutrophil elastase activity and porcine pancreatic elastase activity with respective IC50 values of 83 and 100 nM. FK706, however, inhibited more weakly, (IC50 values > 340 microM) other serine proteinases such as human pancreatic alpha-chymotrypsin, human pancreatic trypsin and human leukocyte cathepsin G. FK706 also effectively inhibited the hydrolysis of bovine neck ligament elastin (2 mg/ml final concentration) by human neutrophil elastase (4 microg/ml final concentration) with an IC50 value of 230 nM. FK706 protected animals against human neutrophil elastase (50 microg/animal)-induced lung hemorrhage with ED50 values of 2.4 microg/animal by intratracheal administration and 36.5 mg/kg by intravenous administration, respectively. Subcutaneous administration of FK706 significantly suppressed human neutrophil elastase (20 microg/paw)-induced paw edema in mice in a dose-dependent manner (47% inhibition at a dose of 100 mg/kg). These results suggest that FK706 would be a useful tool for investigating the role of human neutrophil elastase in inflammatory disorders associated with an excess of elastase, such as pulmonary emphysema, adult respiratory distress syndrome, septic shock, cystic fibrosis, chronic bronchitis and rheumatoid arthritis.

Animals↗