Search PubMed⌕ Search

Biomedical subjects

T Ueno

Publications and source records attributed to T Ueno.

At least 73 records · Page 4Linked to original sources
PubMed2001

Laparascope-assisted versus conventional restorative proctocolectomy with rectal mucosectomy.

To assess the advantages of a laparoscope-assisted proctocolectomy with ileal J-pouch anal anastomosis compared with conventional procedures, we retrospectively analyzed the results of the two procedures as follows: Eleven patients including five patients with familial adenomatous polyposis (FAP) and six with ulcerative colitis (UC) underwent a laparoscope-assisted proctocolectomy and hand-sewn ileal J-pouch anal anastomosis at our department from June 1997 to November 1999. This laparoscope-assisted colectomy (LAC) group was then compared with a group of 13 patients who had undergone conventional ileal pouch anal anastomosis using a standard laparotomy from 1986 to 1997. The median operative time of the LAC group was 8h 23min, which was 81 min longer than that of the standard colectomy (SC) group. The number of days during which eating was prohibited were similar in the two groups but the median postoperative hospital stay was significantly shorter in the LAC group (24.1 days). In the LAC group, the small incisions showed better cosmetic results and there was also a remarkable reduction in the degree of postoperative pain. In conclusion, a laparoscope-assisted proctocolectomy with ileal J-pouch anal anastomosis can be employed widely in patients with FAP and also in selected patients with UC.

Adenomatous Polyposis Coli↗
PubMed2001

Penetrating atherosclerotic ulcer.

The pathogenesis of penetrating atherosclerotic ulcer (PAU) in aortic disease remains controversial. Between January 1995 and April 1999, five patients underwent treatment for a PAU in our hospital. All were men, ranging in age from 46 to 74 years, with a mean age of 66.2 years. The PAU was located on the thoracic descending aorta in three patients and on the abdominal aorta in two. Preoperative diagnosis was established by contrast-enhanced computed tomographic scan and aortogram. Surgery was performed in four patients, as graft replacement in three, and patch plasty in one. The remaining patient is being carefully observed on antihypertensive therapy. No connective tissue disorder, trauma, dissection, or infection was seen in any of the patients who underwent surgery, all of whom had uneventful postoperative courses with no perioperative complications or enlargement of the aorta. We conclude that surgical treatment should be performed for patients with PAU to prevent an aortic catastrophe caused by rapid development of the lesion. This report might provide further evidence of the importance of PAU.

Aged↗
PubMed2001

Modification of virus infectivity by cytoplasmic tail of HIV-1 TM protein.

Envelope glycoprotein incorporation is an essential process in formation of infectious particles of human immunodeficiency virus. Accumulated data have indicated that the cytoplasmic tail of Env gp41 is required for efficient incorporation. By analyzing mutant viruses with truncated cytoplasmic tails, we found that the domain was required in a cell-type-dependent manner for maintaining virus infectivity. Although the viruses with truncated cytoplasmic tails produced from HeLa, A3.01 and SupT1 cells showed a greatly reduced infectivity, those from SW480 and MT-4 cells retained a significant infectivity. To clarify the different effect of the cytoplasmic tail mutation on virus infectivity, we performed biochemical studies on the virions produced from HeLa and SW480 cells. Although the truncation of cytoplasmic tail appeared to reduce the Env incorporation in both cell lines, it caused a significant incorporation of Env precursor with HeLa cells. The results suggested that the cytoplasmic tail regulated selective incorporation of processed Env into virions in a cell-type-dependent manner.

Cell Line↗
PubMed2001

Laminin deposition to type IV collagen enhances haptotaxis, chemokinesis, and adhesion of hepatoma cells through beta1-integrins.

BACKGROUND/AIMS: In hepatocellular carcinoma, laminin deposition to type IV collagen along the sinusoids is observed with the development of arterial network, coinciding with intrahepatic metastasis. We investigated the influence of laminin deposition to type IV collagen on hepatoma cell adhesion, motility and secretion of matrix metalloproteinases (MMPs), which are indispensable behaviors for tumor metastasis. METHODS: Hepatoma cell lines (KYN-1, -2 and -3) were used. The expression of integrin subunit mRNAs in hepatoma cells was confirmed by RT-PCR. The influence of laminin addition to type IV collagen on the adhesion, chemokinesis, and migration of KYN-1, -2 and -3 was evaluated by the haptotactic migration, phagokinetic track motility, and cell adhesion assays. The effects of integrin subunits on these activities were evaluated using the function-blocking antibodies for integrins. Phosphorylation of MEK1/2 and secretion of MMPs were investigated by Western blotting and gelatin zymography. RESULTS: Integrin alpha1, alpha2, alpha3, alpha6 and beta1 subunit mRNAs were detected. The combination of type IV collagen and laminin enhanced the migration, chemokinesis, and adhesion of hepatoma cells compared to that of type IV collagen when used alone. The enhanced activity was significantly suppressed by function-blocking antibodies for integrin alpha1, alpha2, alpha3, alpha6 and beta1 subunits. Hepatoma cells cultured on the combination of type IV collagen and laminin showed phosphorylation of MEK1/2 and increased secretion of MMPs. CONCLUSIONS: The addition of laminin to type IV collagen enhances hepatoma cell adhesion and motility through beta1-integrins.

Carcinoma, Hepatocellular↗
PubMed2001

Enhanced external counterpulsation improves exercise tolerance, reduces exercise-induced myocardial ischemia and improves left ventricular diastolic filling in patients with coronary artery disease.

OBJECTIVES: We examined whether enhanced external counterpulsation (EECP) improves myocardial ischemia, exercise tolerance and cardiac function in patients with coronary artery disease (CAD). BACKGROUND: Enhanced external counterpulsation reduces angina and improves exercise tolerance in patients with CAD. Some objective improvements of ischemia by EECP have been reported, but they should be confirmed further. Detailed hemodynamic effects of EECP have been less well documented. METHODS: Enhanced external counterpulsation was performed for a total of 35 h in patients with stable CAD (n = 12) who showed evidence of exercise-induced myocardial ischemia despite conventional medical or surgical therapies. All patients had significant stenotic lesions in major coronary arteries. RESULTS: Enhanced external counterpulsation improved all exercise test parameters (p < 0.05): exercise duration, time to 1-mm ST segment depression, rate-pressure product at peak exercise and rate-pressure product at 1-mm ST segment depression. Moreover, the prevalence of exercise-induced reversible perfusion defects by thallium scintigraphy decreased after treatment (p < 0.01). Enhanced external counterpulsation did not alter systolic function but improved diastolic filling, left ventricular (LV) end-diastolic pressure (p < 0.05) by cardiac catheterization and LV peak filling rate end-diastolic volume/s (p < 0.01) and time to peak filling rate (p < 0.05) by radionuclide scintigraphy. These hemodynamic improvements were associated with decreased plasma brain natriuretic peptides levels after EECP (p < 0.05). CONCLUSIONS: Thus, EECP treatment improves exercise tolerance and reduced myocardial ischemia by thallium scintigraphy in association with improved LV diastolic filling in patients with stable CAD.

Aged↗
PubMed2001

The impact of ischaemic preconditioning on spinal cord blood flow and paraplegia.

PURPOSE: We investigated the effect of ischaemic preconditioning (IP) on ischaemic spinal cord injury in a rabbit model. METHODS: Fourteen rabbits were divided into IP and control groups of seven rabbits each. We repeated 3-min clamping of the infrarenal abdominal aorta and 3-min reperfusion twice (preconditioning), followed by 15 min clamping in the IP group. In the control group, the aorta was clamped for 15 min without preconditioning. Lumbar cord blood flow and systemic blood pressure were measured until 3 h of reperfusion. Another 14 rabbits underwent the same procedures with or without IP and neurologic status was assessed on the second postoperative day. RESULTS: The percent change in lumbar cord blood flow after reperfusion was significantly greater (P=0.013) in the IP group despite lower mean blood pressure. There was no significant difference in overall neurologic status (P=0.461) but the incidence of spastic paraplegia in the IP group was lower (14%, 1/7) than that of control group (43%, 3/7). CONCLUSION: IP increased postischaemic lumbar cord blood flow and contributed to lower incidence of spastic paraplegia.

Animals↗
PubMed2001

Impairment of an event-related potential correlate of memory in schizophrenia: effects of immediate and delayed word repetition.

OBJECTIVE: We investigated the nature of the memory impairment in schizophrenia using an event-related potential (ERP). METHODS: Visual ERPs were recorded while 20 schizophrenics and 20 controls performed semantic categorization tasks with incidental word repetitions. Participants responded to occasional target words. Half of the non-target words were repeated immediately after initial presentation (lag 0) or after 5 intervening words (lag 5). RESULTS: In both groups, ERPs to words at lag 0 were more positive than those to non-repeated words, though this positive-going effect was attenuated in the schizophrenics, especially around 400-500 ms. The effect at lag 5 was smaller and shorter than that at lag 0 but was comparable between groups. Attenuation of the N400 peak occurred for word repetition at lag 0 in controls but not in schizophrenics, whereas a peak increment in the late positive component induced by word repetition at both lags was observed in both groups. CONCLUSIONS: Findings indicate that patients with schizophrenia have a deficit in a brain process modulating ERP correlates of memory, when words are repeated immediately. This deficit might be related to an abnormal N400 priming effect in schizophrenia.

Adult↗
PubMed2001

Characterization of sago palm (Metroxylon sagu) lignin by analytical pyrolysis.

Dioxane lignin prepared from sago palm (Metroxylon sagu) was characterized by analytical pyrolysis coupled to gas chromatography-mass spectrometry. Large abundances of the p-hydroxybenzoates ester-linked to the lignin were proven by analytical pyrolysis as well as by mild alkaline treatment that produced p-hydroxybenzoic acid in 16.3% yield. Pyrolysis in the presence of tetramethylammonium hydroxide (TMAH) before and after alkaline treatment also showed the presence of ester- and ether-linked p-hydroxybenzoates. Quantitative results of pyrolysis showed that the sago palm lignin is of syringyl type. The relative abundances of TMAH/pyrolysis products derived from the syringyl beta-aryl ether substructures were 4.9 times those of the guaiacyl equivalents. Proton nuclear magnetic resonance analysis also showed the presence of the p-hydroxybenzoates and the predominance of the syringyl moiety over the guaiacyl ones in the sago palm lignin.

Gas Chromatography-Mass Spectrometry↗
PubMed2001

Intraduodenal and intrajejunal administration of the herbal medicine, dai-kenchu-tou, stimulates small intestinal motility via cholinergic receptors in conscious dogs.

The aim of the present study was to study the effect and mechanism of action of intraduodenal and intrajejunal dai-kenchu-to, an herbal medicine clinically effective for uncomplicated postoperative adhesive intestinal obstruction, on upper gastrointestinal motility. Five mongrel dogs were equipped with four strain-gauge force transducers on the antrum, duodenum, and proximal and distal jejunum to measure contractile activity. Dai-kenchu-to (0.5, 1.5, and 3.0 g) was administered into the duodenal or proximal jejunal lumen. The effect of atropine, hexamethonium, phentolamine, propranolol, and ondansetron on intraduodenal and intrajejunal dai-kenchu-to-induced contractions was studied. Plasma motilin was measured by specific radioimmunoassay. Intraduodenal and intrajejunal dai-kenchu-to induced phasic contractions in the duodenum and proximal jejunum, respectively, and those contractions migrated distally. Phasic contractions induced by intraduodenal and intrajejunal dai-kenchu-to were inhibited by atropine and hexamethonium at all sites. Plasma motilin was not affected by dai-kenchu-to. Intraduodenal and intrajejunal dai-kenchu-to stimulates upper gastrointestinal motility at and distal to the administration sites through cholinergic receptors.

Animals↗
PubMed2001

Single-molecule observation of protein-protein interactions in the chaperonin system.

We have analyzed the dynamics of the chaperonin (GroEL)-cochaperonin (GroES) interaction at the single-molecule level. In the presence of ATP and non-native protein, binding of GroES to the immobilized GroEL occurred at a rate that is consistent with bulk kinetics measurements. However, the release of GroES from GroEL occurred after a lag period ( approximately 3 s) that was not recognized in earlier bulk-phase studies. This observation suggests a new kinetic intermediate in the GroEL-GroES reaction pathway.

Adenosine Triphosphate↗
PubMed2001

Changes in auditory P300 with clinical remission in schizophrenia: effects of facial-affect stimuli.

The auditory P300 is affected by arousal and emotion. We examined the effect of drawings expressing sadness or pleasure on auditory event-related potentials (ERP) during recovery from schizophrenia. Oddball-paradigm auditory ERP were recorded while presenting one of these drawings to nine patients with paranoid schizophrenia and seven patients with other types of schizophrenia during the acute stage and again during remission. P300 parameters (amplitude, area, and latency), reaction time, and symptom scores were evaluated. P300 amplitude and area were significantly greater in the recovery than in the acute phase. Increases were larger when viewing drawings that expressed sadness than when viewing drawings that expressed pleasure. In paranoid-type patients, P300 when viewing pleasurable drawings was similar to that when viewing sad drawings during the acute phase; in remission, P300 was significantly larger when viewing sad drawings than when viewing pleasurable drawings. In non-paranoid patients, P300 while viewing pleasurable drawings was significantly larger than that while viewing sad drawings during the acute phase; this difference disappeared during recovery. P300 latency and reaction time were not influenced by facial-affect stimuli or recovery. A significant negative correlation was noted between amplitude and negative symptom scores. P300 amplitude and area may be useful state markers during recovery in schizophrenic patients. Effects involving attention resources and emotional arousal are also involved.

Adolescent↗
PubMed2001

Visual event-related potential in mild dementia of the Alzheimer's type.

Visual event-related potentials (ERP) and behavioral measures were recorded during a geometrical-figure discrimination task to examine sensory processing in 10 patients with mild dementia of the Alzheimer's type (DAT) and 10 age-matched controls. No difference existed between the groups in P1, N1, and P2 potentials, which reflects the early stage of sensory processing, as well as in NA potential, which reflects pattern recognition. The patients showed reduced amplitude of P3 potential, retarded reaction time, and increased behavioral errors compared to controls. These findings suggest that the patients with mild DAT were intact in early sensory processing including pattern recognition but were selectively compromised in higher-level processing, including integration of information and memory matching, which may influence behavioral deviation.

Alzheimer Disease↗
PubMed2001

Guidelines for catheter intervention in coronary artery lesion in Kawasaki disease.

The Research Committee of Ministry of Health, Labour and Welfare 'Study of treatment and long-term management in Kawasaki disease' reported the guidelines for catheter intervention in coronary artery lesion in Kawasaki disease in this paper. The contents include: (i) background and natural history of coronary artery lesion in Kawasaki disease; (ii) indication of catheter intervention; (iii) types of procedure, and their indication and care; (iv) institute and backup system; (v) the management after procedure, evaluation and follow up; and (vi) prospects, especially in relation to bypass surgery.

Angioplasty, Balloon, Coronary↗
PubMed2001

Bidirectional modulation of P2X receptor-mediated response by divalent cations in rat dorsal motor nucleus of the vagus neurons.

The modulatory effects of Zn(2+) and other divalent cations on the ATP-induced responses of preganglionic neurons acutely dissociated from the rat dorsal motor nucleus of the vagus (DMV) were examined using a nystatin-perforated patch technique under voltage-clamp. DMV neurons were identified by back-filling of DiI placed on the vagal bundle at the neck. Zn(2+) exerts a concentration-dependent effect on P2X receptor-mediated current (I(ATP)): a potentiation by low concentrations of Zn(2+) (< or = 50 microM) and an inhibition by high concentrations (> 50 microM). Inhibition of the ATP response was associated with a prolongation of the rising phase of I(ATP). Cu(2+) mimicked Zn(2+) regarding the biphasic modulation of I(ATP). On the other hand, Ni(2+) potentiated, but failed to inhibit, the ATP response even at a concentration of 3 mM. Quantitative RT-PCR revealed the similarity of P2X(2) mRNA expression between the DMV and superior cervical ganglion (SCG) but not in the dorsal root ganglion (DRG) and hypoglossal nucleus (XII). The results from the electrophysiological and molecular approaches suggest that functional P2X receptors expressed in DMV neurons are characterized mainly by the P2X(2) and P2X(2/6) subtype. DMV neurons possess similar P2X receptor characteristics to SCG neurons.

Adenosine Triphosphate↗
PubMed2001

Concentration of progenitor cells collected from bone marrow fluid using a continuous flow cell separator.

In ABO major incompatibility on bone marrow transplantation (BMT), red cells must be removed from collected marrow fluid to prevent hemolysis. We report the concentration of progenitor cells collected using a continuous flow cell separator (Cobe Spectra). The average volume of concentrated bone marrow was 132 +/- 47 ml and that of red cells included was 5.1 +/- 2.4 ml. The red cell removal rate was 97.6%. The recovery rate was 40.6% for total nuclear cells, 77.9% for mononuclear cells, 100% for CD34+ cells, and 93.9% for colony forming unit granulocyte-macrophage. Eighteen patients undergoing allogeneic BMT showed no signs of fever or hemolysis during concentrated marrow fluid transfusion. The recovery rate of progenitor cells was high, indicating sufficient recovery of hemopoiesis. This technique is applicable in ABO-incompatible BMT and in frozen-storage stem cells.

ABO Blood-Group System↗
PubMed2001

Involvement of p21(WAF1/Cip1), p27(Kip1), and p18(INK4c) in troglitazone-induced cell-cycle arrest in human hepatoma cell lines.

Peroxisome proliferator-activated receptor gamma (PPARgamma) regulates cell growth and differentiation. Recent evidence has suggested that PPARgamma ligands had anti-tumor effects through inhibiting cell growth and inducing cell differentiation in several types of malignant neoplasm. In the present study, we investigated: 1) the expression of PPARgamma in both human hepatoma cell lines and 5 resected human hepatocellular carcinoma (HCC) tissues; 2) the growth-inhibitory effect of troglitazone, a PPARgamma ligand, on those hepatoma cells; and 3) the molecular mechanisms of troglitazone-induced cell-cycle arrest. Five hepatoma cell lines, HLF, HuH-7, HAK-1A, HAK-1B, and HAK-5, were used. The mRNA expression levels of PPARgamma, p21(WAF1/Cip1), and p27(Kip1) were determined by real-time quantitative reverse transcription-polymerase chain reaction. The expression of cell cycle-regulating proteins, such as p21, p27, p18(INK4c), cyclin E, and pRb, was examined using Western blotting. PPARgamma was constitutively expressed in all the cell lines and the HCC tissues used in this study. A cytostatic effect of troglitazone was found in those cell lines, and this inhibition of cell growth was dosage-dependent. G0/G1 arrest was apparently demonstrated in flow cytometric analysis in HLF, HAK-1A, HAK-1B, and HAK-5, all of which showed an increased expression of p21 protein. However, HuH-7, lacking p21 protein expression, did not demonstrate clear arrest in the cell-cycle analysis. HLF, which was deficient in the protein product of the retinoblastoma tumor-suppressor gene (pRb), responded most profoundly to troglitazone, showing an increased expression in not only p21, but also in p27 and in p18. These findings suggested that p21, p27, and p18 might be involved in troglitazone-induced cell-cycle arrest in human hepatoma cells.

CDC2-CDC28 Kinases↗
PubMed2001

Autocrine motility factor enhances hepatoma cell invasion across the basement membrane through activation of beta1 integrins.

Autocrine motility factor/phosphohexose isomerase (AMF/PHI) is a cytokine that is linked to tumor invasion and metastasis. In hepatocellular carcinoma (HCC) tissues, hepatoma cells produce AMF/PHI and its receptor, Mr 78,000 glycoprotein (gp78), is strongly detected in hepatoma cells invading into the stroma and tumor thrombi in the portal vein. Here, we investigated the mechanism of hepatoma cell invasion through Matrigel induced by AMF/PHI using 3 hepatoma cell lines. Production of AMF/PHI, phosphorylation of MEK1/2, and Rho activity were investigated by immunoblotting. Expression of AMF/PHI and gp78 was observed by confocal fluorescence microscopy. The influence of AMF/PHI on activated integrin beta1 subunit expression was evaluated by flow cytometry. Changes in invasion, adhesion, and motility induced by AMF/PHI were evaluated using chemoinvasion, adhesion, and phagokinetic track motility assays. The effect of AMF/PHI on matrix metalloproteinase (MMP) secretion was evaluated by gelatin zymography. Hepatoma cells produced AMF/PHI and expressed gp78. Although AMF/PHI was ubiquitously detected, gp78 was strongly expressed in migrating cells. AMF/PHI induced up-regulation of activated integrin beta1 subunit expression. AMF/PHI stimulated hepatoma cell invasion through Matrigel, and stimulated the adhesion, motility, and MMP-2 secretion of hepatoma cells. The latter effects were suppressed by the function-blocking antibody for integrin beta1 subunit. AMF/PHI also enhanced Rho activity and the phosphorylation of MEK1 and MEK 2. Our results indicate that AMF/PHI enhances hepatoma cell invasion through Matrigel in an autocrine manner by stimulating the adhesion, motility, and MMP-2 secretion of these cells through activation of beta1 integrins.

Basement Membrane↗