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Takashi Ono

Publications and source records attributed to Takashi Ono.

At least 37 records · Page 2Linked to original sources
PubMed2004

Modulation of voluntary swallowing by visual inputs in humans.

The purpose of this study was to test the hypothesis that a stimulus which strengthens a central input to a swallowing-related cortical area, given before voluntary swallowing, could facilitate subsequent swallowing movements. The subjects consisted of seven healthy volunteers. We used visual images to strengthen central input. The subjects voluntarily performed either dry swallowing or water swallowing after presentation of the visual images. Under the water-swallowing condition, the latency was significantly shorter and the maximum amplitude of the suprahyoid electromyographic (EMG) activity was significantly smaller in subjects who received drink-related visual input. However, there were no similar differences under the dry-swallowing condition. In addition, there were no significant differences in the mean EMG amplitude or the duration of EMG activity between subjects who did and did not receive drink-related visual input under either swallowing condition. We concluded that drink-related visual inputs prior to voluntary swallowing facilitate the initiation of swallowing and enhance swallowing-related muscle activity in the presence of peripheral inputs.

Adult↗
PubMed2004

Expression of gap junction protein connexin32 in chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma.

BACKGROUND: The gap junction (GJ) plays important roles in the maintenance of tissue homeostasis, the control of cell growth and differentiation, and the prevention of experimental hepatocarcinogenesis. In this study, we examined the relationship between the expression of the GJ protein connexin (Cx) 32 in 24 human hepatocellular carcinomas (HCCs) and 29 non-carcinomatous liver specimens (NCLs) of 31 patients. METHODS: An immunohistochemical study of Cx32 was done in 24 HCCs and 29 NCLs from 31 patients who had undergone hepatic resection. RESULTS: The Cx32 expression decreased gradually as the disease progressed to cirrhosis and HCC. In all Cx32 positive HCCs, the expression was mostly recognized in cytoplasm, not only on the cell membrane. This internalization of Cx32 was also recognized in liver specimens showing hepatitis and cirrhosis, although it was less frequent than in the HCCs. CONCLUSIONS: These findings suggest the possibility that changes in both the amount and the distribution of Cx32 may be implicated in human hepatocarcinogenesis.

Aged↗
PubMed2004

Mesojejunal lymph node metastasis in esophageal cancer following total gastrectomy.

We report on a case of thoracic esophageal cancer following total gastrectomy (rho-Roux-en-Y reconstruction) with metastasis to the mesojejunal lymph nodes. Subtotal esophagectomy with reconstruction using pedicled colon and dissection of two lymph node fields was performed. During the operation, we found three lymph nodes showing metastasis at the rho-Roux loop of the mesentery, and resected the rho-Roux loop. The route of the lymphatic drainage to the abdomen from the thoracic tumor seemed to have been changed by the prior gastrectomy. Based on the pathological findings, the case was diagnosed with T2N4M0, Stage IVa. We did not confirm that the distant metastases skipped the mesojejunal lymph nodes preoperatively; the distant metastases were detected accidentally by lymphoscintigraphy using technetium-99m tin colloid. We believe this case highlights the need for detailed examinations in esophageal cancer patients who have had prior gastrectomy.

Aged↗
PubMed2004

Oral appliance titration and nasal resistance in nonapneic subjects.

Initial mandibular position might be a key factor leading to rapid therapeutic outcome in oral appliance therapy for patients with obstructive sleep apnea (OSA). The purpose of this study was to investigate the effects of an adjustable oral appliance on nasal resistance in 7 nonapneic patients. Upright and supine nasal resistance was measured for each subject with an adjustable oral appliance in place in 3 mandibular positions: most retruded (MAX0), maximum protrusion (MAX100), and 67% of MAX100 (MAX67). A significant decrease in upright and supine nasal resistance was observed between MAX0 and MAX67 (P < .01), and between MAX0 and MAX100 (P < .01), but not between MAX67 and MAX100. In addition, there was a positive correlation between the nasal resistance at MAX0 and the nasal resistance change from MAX0 to MAX67 (P < .01), indicating that when the mandible was advanced from MAX0 to MAX67, the more nasal resistance at MAX0, the greater the reduction in nasal resistance at MAX67. These findings suggest that MAX67 might be indicated as the initial mandibular position and that gradual anterior titration of mandibular position beyond MAX67 would give OSA patients rapid therapeutic effects by reducing the nasal resistance. Moreover, OSA patients with augmented nasal resistance at MAX0 might have a greater reduction in nasal resistance in response to MAX67 in oral appliance therapy.

Adult↗
PubMed2004

Doxycycline inhibits cell proliferation and invasive potential: combination therapy with cyclooxygenase-2 inhibitor in human colorectal cancer cells.

Matrix metalloproteinases (MMPs) and cyclooxygenase (COX) enzymes play pivotal roles in the metastatic process of colorectal cancers. Inhibition of both MMPs and COX could be an attractive option for the inhibition of cell growth and invasion. Two human colorectal cancer cell lines, LS174T and HT29, were challenged with MMP inhibitor (doxycycline), selective COX-2 inhibitor (NS-398), or a combination of these agents to evaluate cancer cell proliferation and invasion. Dose-dependent growth inhibition was observed in both cell lines when they were treated with a single therapy. These effects were not related to MMP-2 or MMP-9 expression potential of the cell lines. Doxycycline (10 microg/mL) induced G(0)/G(1) arrest, and 20 microg/mL provoked annexin V positivity and up-regulated caspase-3 activity in HT29 cells. However, 20 microg/mL doxycycline caused no distinct apoptotic change in LS174T cells. Although MMP expression was not inhibited by 5 to 10 microg/mL doxycycline or 50 to 100 micromol/L NS-398, MMPs' activities were down-regulated by these concentrations. Cellular invasion was noticed in LS174T cells, but their capacity for invasion was diminished by these inhibitors. The antiproliferative and antiinvasive effects of the combination therapy were more pronounced. Doxycycline (5 microg/mL) with 50 micromol/L NS-398 inhibited cell proliferation and doxycycline (5 microg/mL) with 100 micromol/L NS-398 attenuated MMP expression and activity, as well as capacity for invasion, compared with single therapy. These data suggest that combination therapy consisting of an MMP inhibitor with a COX-2 inhibitor is an attractive approach to the treatment of colorectal cancers. The use of this treatment regimen for chemoprevention or treatment of colorectal cancers should be considered in future clinical trials.

Adenocarcinoma↗
PubMed2004

Effect of titrated mandibular advancement and jaw opening on the upper airway in nonapneic men: a magnetic resonance imaging and cephalometric study.

The aim of this study was to examine adaptive changes in the cross-sectional area of the upper airway during mandibular advancement and jaw opening and to explore whether these changes are directly related to morphologic features of the mandible. Fourteen nonapneic men participated in this study. A custom-made oral device was used to keep the mandible at 0% (F(0)V(0)), 50% (F(50)V(0)), 75% (F(75)V(0)), or 100% (F(100)V(0)) of maximum advancement, and at 50% (F(75)V(50)), 75% (F(75)V(75)), or 100% (F(75)V(100)) of maximum gape at F(75)V(0). Magnetic resonance imaging was used to investigate differences in the upper-airway cross-sectional area in these 7 positions. To eliminate excessive individual variation, changes in the mean (mean%) and minimum (min%) cross-sectional area of the upper airway were calculated as percentages of those at F(0)V(0). Cephalograms were taken to analyze morphologic features of the mandible. A dose-dependent change was seen when the mandible was advanced. The min% in F(100)V(0) was significantly greater than those in F(50)V(0) and F(75)V(0). The change in the upper airway size varied between subjects during jaw opening. At F(75)V(0), the min% of the whole upper airway was significantly associated with morphologic features of the mandible, such as the mandibular plane angle and lengths of the mandibular body and ramus.

Adaptation, Physiological↗
PubMed2004

Transforming growth factor-beta1 induced hepatocyte apoptosis--a possible mechanism for growth of colorectal liver metastasis.

The mechanisms of colonization and growth of metastatic liver tumors from colorectal cancers remain obscure. Forty-three resected colorectal metastatic liver tumors with surrounding livers were evaluated for apoptotic index (AI), proliferation index (PI), and immunohistochemical expressions of TGF-beta1. TGF-beta receptor II, Fas, and Fas-ligand. All the parameters were significantly higher in the peri-tumoral livers than in the tumors with the exception of PI, which was significantly high in tumors. Enhanced TGF-beta1 expression was noticed at the interface between the metastatic tumor and the adjacent liver parenchyma. The AIs of hepatocytes in the TGF-beta1-positive areas (8.7 +/- 7.5%, n = 43) were significantly higher when compared with those in the TGF-beta1-negative areas (2.4 +/- 4.5%, n = 42) (p < 0.001). However, the same kind of correlation could not be found in metastatic tumors. The enhanced expression of TGF-beta1 and hepatocyte apoptosis in the peri-tumoral liver parenchyma may suggest that TGF-beta1 plays a substantial role in the development of colorectal liver metastasis.

Aged↗
PubMed2004

Validity of the adaptive filter for accurate measurement of cardiac output in impedance cardiography.

The purpose of this study was to assess the validity of an adaptive filter, the scaled Fourier linear combiner (SFLC), in the impedance cardiography (ICG). Eight healthy males underwent constant-load bicycle exercise at different intensities from unloaded to near maximal intensity. The stroke volume (SV) and cardiac output (Q) measured by ICG at each condition were compared with those by the CO2 rebreathing method. We found that the noises were greatly reduced in the impedance waveform and that the inflection points, so-called the B- and X-points, were clearly detected even during strenuous exercise using the SFLC. Although a high correlation was observed between Qs measured by the two methods, the mean values of Qs in each method differed significantly and the regression line also differed significantly from the identity line. Likewise, a significant correlation was observed between SVs obtained by the two methods, but a significant difference in the group mean values and a trend of the regression line were observed. These findings suggest that the use of SFLC in ICG improves the performance in eliminating the noises and in detecting the inflection points in the waveform, thereby contributing to the accurate and beat-to-beat measurements of SV and Q especially during exercise.

Adult↗
PubMed2004

Beat-to-beat evaluation of systolic time intervals during bicycle exercise using impedance cardiography.

In order to elucidate the beat-to-beat changes of the systolic time intervals (STI) during exercise, we proposed new techniques relating to an adaptive filter and detection algorithms for B- and X-points in the impedance cardiograph (ICG). Six male subjects underwent a ramp bicycle exercise up to maximum intensity during which an ECG, ICG and phonocardiogram (PCG) were continuously measured. Following the application of an adaptive filter, the scaled Fourier linear combiner (SFLC), to the first derivative (dZ/dt) of the base impedance (deltaZ) and PCG waveforms, the B- and X-points were automatically determined. For the B-point detection we used three criteria: the zero-crossing point (B(zero)), the 15% response point (B15%) of the negative peak of the dZ/dt (dZ/dt(min)) and a new algorithm (B(new)). The X-point was separately determined by using the ICG and PCG waveforms. It was found that the shape of the dZ/dt waveform directly affected the determination of the B- and X-points. The B-points determined using B(zero) and B15%, criteria were sometimes unstable caused by the location of a notch preceding the dZ/dt(min) compared to the B(new). The time difference between the X-points measured by the ICG and PCG was mostly within +/- 20 milliseconds but statistically significant. Although a wide variation was seen in R-R intervals, the STI were more stable. The relationships between HR and STI from rest to maximal exercise showed a gentle curvilinear relationship. It is suggested that the STI can be obtained precisely on a beat-to-beat basis by using the adaptive filter and detection algorithms for the inflection points of the ICG even during maximum exercise.

Adult↗
PubMed2004

Comparison of fMRI data analysis by SPM99 on different operating systems.

The hardware chosen for fMRI data analysis may depend on the platform already present in the laboratory or the supporting software. In this study, we ran SPM99 software on multiple platforms to examine whether we could analyze fMRI data by SPM99, and to compare their differences and limitations in processing fMRI data, which can be attributed to hardware capabilities. Six normal right-handed volunteers participated in a study of hand-grasping to obtain fMRI data. Each subject performed a run that consisted of 98 images. The run was measured using a gradient echo-type echo planar imaging sequence on a 1.5T apparatus with a head coil. We used several personal computer (PC), Unix and Linux machines to analyze the fMRI data. There were no differences in the results obtained on several PC, Unix and Linux machines. The only limitations in processing large amounts of the fMRI data were found using PC machines. This suggests that the results obtained with different machines were not affected by differences in hardware components, such as the CPU, memory and hard drive. Rather, it is likely that the limitations in analyzing a huge amount of the fMRI data were due to differences in the operating system (OS).

Adult↗
PubMed2003

Carrier doping effect into quasi-one-dimensional bromo-bridged Ni(III) complexes with strong electron-correlation by Cu(II) ions, [Ni1-xCux(chxn)2Br]Br2-x.

This communication will describe the electron doping effect into Ni(III) complexes by Cu(II) ions, [Ni(1-x)Cu(x)(chxn)(2)Br]Br(2-x) (x = 0.038 and 0.101) by using an electrochemical oxidation method. A drastic increase of electrical conductivity as well as a new absorption band around 0.5 eV in single crystal reflectance spectra was observed by doping Cu(II) ions, indicating the electron doping was successfully made. An ESR result shows unpaired electrons locate in the d(x2-y2) orbitals of Cu(II) and have almost no interaction with those of other ions.

Journal Article↗
PubMed2003

Group V and X secretory phospholipase A(2)s-induced modification of high-density lipoprotein linked to the reduction of its antiatherogenic functions.

The quantitative or qualitative decline of high-density lipoprotein (HDL) is linked to the pathogenesis of atherosclerosis because of its antiatherogenic functions, including the mediation of reverse cholesterol transport from the peripheral cells to the liver. We have recently shown that group X secretory phospholipase A(2) (sPLA(2)-X) is involved in the pathogenesis of atherosclerosis via potent lipolysis of low-density lipoprotein (LDL) leading to macrophage foam cell formation. We demonstrate here that sPLA(2)-X as well as group V secretory PLA(2) (sPLA(2)-V), another group of sPLA(2) that can potently hydrolyze phosphatidylcholine (PC), also possess potent hydrolytic potency for PC in HDL linked to the production of a large amount of unsaturated fatty acids and lysophosphatidylcholine (lysoPC). In contrast, the classical types of group IB and IIA secretory PLA(2)s evoked little, if any, lypolytic modification of HDL. Treatment with sPLA(2)-X or -V also caused an increase in the negative charge of HDL with no oxidation and little modification of apolipoprotein AI (apoAI). Modification with sPLA(2)-X or -V resulted in significant decrease in the capacity of HDL to cause cellular cholesterol efflux from lipid-loaded macrophages. Immunohistochemical analysis revealed significant expression of sPLA(2)-X in foam cell lesions in the arterial intima of Watanabe heritable hyperlipidemic (WHHL) rabbit. These findings suggest that lipolytic modification of HDL by sPLA(2)-X or -V causes drastic change of HDL in terms of the production of a large amount of unsaturated fatty acids and lysoPC linked to the reduction of its antiatherogenic functions. These sPLA(2)-mediated modifications of plasma lipoproteins might be relevant to the pathogenesis of atherosclerosis.

Animals↗
PubMed2003

Role of group IIA phospholipase A2 in rat colitis induced by dextran sulfate sodium.

Although group IIA phospholipase A(2) has been suggested to be implicated in inflammatory bowel disease, its pathophysiological role in colitis remains unclear. We investigated whether group IIA phospholipase A(2) had pro-inflammatory roles in dextran sulfate sodium-induced colitis in the rat. Secretory phospholipase A(2) activity was markedly increased in the distal colon with two peaks. Strong immunostaining for group IIA phospholipase A(2) was found in subepithelial tissue and lamina propria at early stage and in deeper tissues of the erosion area at later stage. Treatment with a specific group IIA phospholipase A(2) inhibitor, S-3013/LY333013 (methyl[[3-(aminooxoacetyl)-2-ethyl-1-(phenylmethyl)]-1H-indol-4yl]oxy) acetate), reduced erosion area, shortening of colon and colonic inflammation, and strongly inhibited the increase in secretory phospholipase A(2) activity and moderately reduced myeloperoxidase activity in the colon in vivo, while eicosanoid levels were not affected. Marked group IIA phospholipase A(2) expression in the erosion area and the improvement of colitis by the group IIA phospholipase A(2) inhibitor strongly suggest that this enzyme plays pro-inflammatory roles in this colitis model.

Animals↗
PubMed2003

Effects of mandibular advancement on supine airway size in normal subjects during sleep.

STUDY OBJECTIVES: To examine changes in the upper-airway dimension and its surrounding structures induced by mandibular advancement during sleep. DESIGN: Eleven nonapneic adult males participated in the study. A set of supine lateral cephalograms was taken for each subject at the end of expiration during stage 1 and 2 non-rapid-eye-movement sleep with and without a Klearway appliance (Great Lakes Orthodontics, NY, USA), which was adjusted to 67% of the maximum protrusion position. The Wilcoxon signed-rank test was used to compare changes in the anteroposterior width of the upper airway and the positions of the hyoid bone and third cervical vertebra with and without the appliance. SETTING: N/A. PATIENTS OR PARTICIPANTS: N/A. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: The amount of jaw opening was significantly increased by wearing the titratable oral appliance, and the mandibular symphysis moved backward. The sagittal dimension of the superior pharyngeal airway was significantly increased; however, no significant changes were found in the middle and inferior pharyngeal airway. Significant posterior displacement of the hyoid bone and third cervical vertebra was seen. Moreover, significant inferior displacement of the hyoid bone was also seen. The relationship among the mandibular symphysis, the hyoid bone, and the third cervical vertebra remained constant. CONCLUSIONS: Mandibular advancement significantly increases the size of the upper airway in the velopharynx and results in posteroinferior displacement of the hyoid bone and posterior displacement of the third cervical vertebra during sleep.

Adult↗
PubMed2003

Sequential changes of connexin32 and connexin26 in ischemia-reperfusion of the liver in rats.

Serial changes in expression of hepatic gap junction components, connexin32 and connexin26 expressions during ischemia (60 min)-reperfusion injury of the liver were evaluated by immunofluorescence staining and reverse transcription-polymerase chain reaction in rats. Hepatic tissue calcium content and liver enzymes (aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase), were also examined. Connexin expressions were down-regulated during ischemia and steeply increased during the early reperfusion period. This upsurge in connexin was coincided with the augmentation in tissue calcium content level. And the mRNA levels of connexin changed in parallel with the connexin protein level until 60 min after reperfusion. Since it is known that the changes in intracellular Ca(2+) concentration controls the intercellular communication via gap junction, these findings suggest the possibility that gap junction may play a definitive role in reperfusion injury of the liver. Further studies may be necessary to clarify the exact role of connexins in hepatic ischemia-reperfusion injury.

Journal Article↗
PubMed2003

Effects of experimental nasal obstruction on human masseter and suprahyoid muscle activities during sleep.

The effect of nasal obstruction on nocturnal masseter and suprahyoid muscle activities using a newly developed portable electromygram (EMG)-recording unit was examined. Ten healthy Japanese males participated in this study. EMG activities of both the right masseter and bilateral suprahyoid muscles were recorded with a portable EMG-recording unit. At midnight, the subject was asked to lie on a bed after complete preparation with surface electrodes. After maximal clenching and jaw-opening effort (100% maximum voluntary contribution), the subject was allowed to fall asleep. In the first half of the night, EMG activities were recorded for about three hours of sleep without nasal obstruction. In the second half of the night, EMG activities were recorded for about three hours of sleep with nasal obstruction. In both muscles, there were no significant changes in either the maximal EMG activities or the number of events beyond 40% MVC with nasal obstruction. But in an evaluation based on the distribution of muscle activities, the EMG activity of the masseter muscle tended to decrease (P = .07) and that of the suprahyoid muscles increased significantly (P = .02) with nasal obstruction. These results suggest that nasal obstruction could modulate the activities of the masseter and suprahyoid muscles during sleep.

Adult↗
PubMed2003

Usefulness of arthroscopic surgery in hip trauma cases.

PURPOSE: The goal of this study is to clarify the usefulness of arthroscopic surgery as an adjunct in the management of hip trauma. TYPE OF STUDY: Clinical case series. METHODS: Eleven joints from 10 hip trauma cases were studied. All joints had been injured in traffic accidents. Seven joints were classified as Thompson and Epstein (T-E) type I, 2 joints as type II, and 1 joint as type IV. The remaining case was a fracture of the acetabular weight-bearing region that was not included within these classifications. The 5 femoral head fractures associated with hip dislocation were further classified according to Pipkin: 3 joints were type 1, 1 joint was type 2, and 1 joint was type 3. The interval from injury to arthroscopy ranged from 1 to 7 days, with a mean of 3.2 days. RESULTS: In 7 cases, small free osteochondral or chondral fragments that were not detectable on either plain radiographs or computed tomography scans were seen arthroscopically. These fragments were debrided. Arthroscopic osteosynthesis using absorbable pins and fragment extraction were performed in 1 case each of the Pipkin's type 1 femoral head fractures. In the case of the acetabular weight-bearing region fracture, reduction and percutaneous pinning were performed under arthroscopic observation. After a mean postoperative follow-up period of 9 years and 6 months, no abnormalities were observed in 9 of the joints. However, the T-E type IV joint developed osteoarthritis and the Pipkin type 3 joint developed aseptic osteonecrosis of the femoral head. CONCLUSIONS: Arthroscopic surgery allows procedures such as washout and debridement of small free osteochondral and chondral fragments, which were previously neglected in T-E type I and II dislocations despite the fact that they may cause osteoarthritis. In addition, arthroscopic surgery allows procedures such as the extraction or osteosynthesis of fracture fragments in cases associated with femoral head fractures.

Accidents, Traffic↗