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T Ohno

Publications and source records attributed to T Ohno.

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

Expansion of an ablated site and induction of apoptosis after microwave coagulation therapy in rat liver.

BACKGROUND/PURPOSE: Microwave coagulation therapy (MCT), one of the ablation therapies, has been widely used to treat liver cancers, yielding excellent clinical results. Despite its efficacy, the precise events that take place in the ablated liver after MCT remain unknown. We investigated sequential histologic changes around MCT sites and the relationship between MCT and apoptosis in rat liver. METHODS: One session of MCT at 30 W was applied to rat liver. The rats were killed at 0, 2, 6, 12, 24, 72, and 168 h after MCT. The liver surface area was measured for sequential evaluations of the size of the impaired field (i.e., the liver surface affected by MCT). The size of the impaired field was assessed by measuring the area that showed macroscopic changes in color with a relatively clear border. To assess apoptosis, we examined terminal deoxynucleotidyl transferase d-uridine triphosphate nick end labeling stained sections, determined the positive cell count for DNA fragmentation, and observed DNA ladder formation by gel electrophoresis. Caspase-3 activity at the ablated margin was measured for the enzymatic evaluation of apoptosis. RESULTS: The impaired field gradually expanded through 12 h after MCT. Caspase-3 activity increased four fold from the baseline, peaking at 2 h after MCT, and DNA fragmentation, confirmed by DNA ladder formation, was significantly increased at 6 h. CONCLUSIONS: Alterations in the ablated liver tissue indicated that the activation of caspase-3 around the MCT site was followed by apoptosis and expansion of the impaired field. The expansion continued until 12 h after MCT, and this may be beneficial for the local control of liver cancer.

Animals↗
PubMed2001

Preventive antitumor activity against hepatocellular carcinoma (HCC) induced by immunization with fusions of dendritic cells and HCC cells in mice.

BACKGROUND: The prevention of recurrence of hepatocellular carcinoma (HCC) after treatment is very important for improvement of the prognosis of HCC patients. Dendritic cells (DCs) are potent antigen-presenting cells that can prime naive T cells to induce a primary immune response. We attempted to induce preventive antitumor immunity against HCC by immunizing BALB/c mice with fusions of DCs and HCC cells. METHODS: Murine bone marrow-derived DCs and a murine HCC cell line. BNL cells, were fused by treatment with 50% polyethyleneglvcol (PEG). Fusion efficacy was assessed by the analysis of fusions of BNL cells stained with red fluorescent dye and DCs stained with green fluorescent dye. Mice injected intravenously with DC/BNL fusions were challenged by BNL cell inoculation. RESULTS: About 30% of the PEG-treated non-adherent cells with both fluorescences were considered to be fusion cells. The cell fraction of DC/BNL fusions showed phenotypes of DCs, MHC class II, CD80, CD86, and intercellular adhesion molecule (ICAM)-1, which were not expressed on BNL cells. Mice immunized with the fusions were protected against the inoculation of BNL tumor cells, whereas injection with a mixture of DCs and BNL cells not treated with PEG did not provide significant resistance against BNL cell inoculation. Splenocytes from DC/BNL fusion-immunized mice showed lytic activity against BNL cells. CONCLUSIONS: These results demonstrate that immunization with fusions of DCs and HCC cells is capable of inducing preventive antitumor immunity against HCC.

Animals↗
PubMed2001

A group of five parameters as a new biological marker on F344/N rats.

The National Institute for Longevity Sciences (NILS) established an aging farm (A/F) for producing aging/aged laboratory rodents at the Experimental Animal Facility Wing under the NILS A/F Guide planned by the Laboratory Animal Research Facilities (LARF). Five parameters, the average life span, the number of days of 75, 50, and 25% survival points, and average of the top 10 longest life span among laboratory strains of rodents at NILS-A/F, were reproducible for F344/N rats specifically by strain and sex under the LARF A/F guide. These five parameters may serve as an effective and practical biological marker, especially in aging science including longevity science, to evaluate characteristics of strains of laboratory rodents. The five parameters can identify clear substrain differences between F344/N and F344/Du and breeder differences between F344/DuCrj and F344/DuCrl.

Journal Article↗
PubMed2001

Transmission electron microscopy of fine aromatic hydrocarbon particles.

Fine perylene and pyrene particles were produced by evaporation in helium gas. The particles were sensitive to electron beam radiation. The pyrene particles sublimed under observation. These difficulties were cleared up by reducing electron beam exposure and sandwiching a specimen between two Formvar films. The fine perylene particles were rectangular or hexagonal plates about 50nm thick. The size was about 200-2000nm. The fine pyrene particles were polymorphic with a size of about 300-2000nm. The crystal forms of the perylene and pyrene particles were determined from the electron diffraction patterns to be alpha-perylene and pyrene I, respectively.

Journal Article↗
PubMed2001

A rise of the serum level of von Willebrand factor occurs before clinical manifestation of the severe form of ovarian hyperstimulation syndrome.

BACKGROUND: Ovarian hyperstimulation syndrome (OHSS) appears to be caused by increased capillary permeability in the vascular endothelial cells. Such cells secrete excess amounts of von Willebrand factor (vWF), a large adhesive glycoprotein. METHODS: We retrospectively evaluated the circulating levels of vWF and of vascular endothelial growth factor (VEGF) twice, on the days of oocyte retrieval and embryo transfer, in 46 women who developed early-onset OHSS. RESULTS: Nineteen, 14, and 13 women developed mild, moderate, and severe OHSS, respectively. Inconsistent changes were observed in the VEGF during oocyte retrieval and embryo transfer. However, the net increase in serum vWF during that period showed an increase in absolute value at the time of embryo transfer that paralleled an increase in the severity of OHSS. That is, in mild OHSS, the serum vWF increased from 140 +/- 44 to 164 +/- 28%; in moderate OHSS, it increased from 113 +/- 47 to 186 +/- 22%; and in severe OHSS, it increased from 120 +/- 35 to 274 +/- 63%. All 9 women with a vWF level > 230% at embryo transfer developed severe OHSS, while 9 of 13 women with severe OHSS exhibited a vWF > 230% at embryo transfer. CONCLUSION: The results suggest that a rise of the serum level of vWF occurs prior to clinical manifestation of OHSS in patients with severe OHSS but not in patients with mild OHSS.

Adult↗
PubMed2001

Successful autologous peripheral blood stem cell transplantation for relapsed intravascular lymphomatosis.

We describe a case of relapsed intravascular lymphomatosis (IVL) successfully treated with autologous PBSCT. A 59-year-old Japanese female patient with IVL who had achieved CR after six courses of biweekly CHOP therapy developed lymphoma. She achieved a second CR after six courses of modified biweekly CHOP therapy, followed by autologous PBSCH and high-dose chemotherapy (CBDCA, VP-16, MCNU, CY) with PBSCT. There has not been any evidence of recurrence 48 months after PBSCT. Our case suggests that PBSC is acceptable as a source for stem cell rescue in IVL.

Antigens, CD34↗
PubMed2001

Purification and properties of the cell-associated beta-xylosidase from Aureobasidium.

beta-Xylosidase was extracted from Aureobasidium sp. ATCC 20524 and purified to homogeneity. The molecular mass was estimated at 411 kDa. The enzyme contained 15.3% (w/w) carbohydrate. The optimum pH and temperature were pH 3.5 and 80 degrees C, respectively. The enzyme was stable at pH 3.5-9 after 3 h and at 80 degrees C after 15 min. The Michaelis constant (K(m)) and maximum velocity (V(max)) toward p-nitrophenyl-beta-D-xyloside were 2.0 mmol l(-1) and 0.94 mmol min(-1) mg(-1) protein, respectively. The enzyme was inhibited strongly by mercury, lead, and copper ions.

Copper↗
PubMed2001

Hypermethylation of p16INK4A gene promoter during the progression of plasma cell dyscrasia.

Recent studies have indicated a close relationship between inactivation of tumor suppressor genes (TSGs) and disease progression. The genes encoding the cyclin-dependent kinase inhibitors p16INK4A and p15INK4B are potent TSGs, and correlations between their inactivation and disease progression have also been reported in various malignancies. In this study, we analyzed the methylation status of p16INK4A and p15INK4B gene promoters in plasma cell dyscrasias (PCDs) by methylation-specific PCR (MSP). In analyses using DNAs extracted from bone marrow mononuclear cells (BM-MNCs), patients with multiple myeloma (MM) showed frequent hypermethylation of the p16INK4A gene (15/37, 41%), whereas p15INK4B gene methylation was not so frequent (5/37, 14%). Many patients whose BM-MNC showed dense methylation of the p16INK4A gene had extramedullary plasmacytoma (extra-PC), and all available extra-PC samples showed alterations of the p16INK4A gene (4; dense methylation, 1; homozygous deletion). In contrast to MM, hypermethylation of the p16INK4A gene was significantly infrequent in indolent PCDs (2/22, 9%, P= 0.0055). The infrequency in indolent PCDs was also confirmed by analyses using DNAs extracted from BM smears (1/29, 3%). It is possible that hypermethylation of the p16INK4A gene promoter contributes to progression to aggressive MM from indolent PCD, especially to extra-PC development.

Biomarkers↗
PubMed2001

Effects of albumin infusion therapy on total and unbound bilirubin values in term infants with intensive phototherapy.

BACKGROUND: The purpose of the present study was to evaluate the effect of intravenous albumin administration on the serum total and unbound bilirubin values in term non-hemolytic hyperbilirubinemic neonates during intensive phototherapy. METHODS: Fifty-eight infants (gestational age 39.4 +/- 1.4 weeks; birth weight 3,245 +/- 435 g) were given phototherapy with similar light energy. Twenty infants (control group) received only phototherapy, while 38 others (albumin-treated group) were also given human albumin at 1 g/kg bodyweight, i.v., during the first 2 h of phototherapy. RESULTS: When comparing changes in total and unbound bilirubin values 0, 2, 6 and 24 h after entering the study between the albumin-treated group and the control group, there was a significant reduction in the serum unbound bilirubin values at the end of albumin treatment and at 6 and 24 h. However, there was no significant reduction in total serum bilirubin values during the study period. In the albumin-treated group, the mean serum unbound bilirubin reduction from the baseline level at the end of albumin treatment and at 6 and 24 h was 0.40 +/- 0.19, 0.41 +/- 0.20 and 0.43 +/- 0.20 microg/dL, respectively. CONCLUSIONS: The results suggest that albumin priming may be effective for an immediate reduction in serum unbound bilirubin values, the fraction that is potentially neurotoxic.

Albumins↗
PubMed2001

Ganglioside as an endogenous growth suppressor for glomerular mesangial cells.

BACKGROUND: Glomerular mesangial cells potentially secrete many growth-modulating substances that could regulate mesangial cell proliferation. To date, however, the properties of such factors have not been fully evaluated. METHODS: For that purpose, conditioned medium (CM) from mesangial cells was used for cross-feeding experiments. Cell proliferation was evaluated by 3H-thymidine incorporation assay and direct cell counting. The growth-regulatory molecule was further characterized using biochemical techniques. RESULTS: Cross-feeding this CM to mesangial cells in vitro, despite stimulation with platelet-derived growth factor (PDGF), effectively suppressed the cells' synthesis of DNA in a dose-dependent manner. The inhibitory substance derived from mesangial cells was less than 3 kD in molecular mass, was heat stable, and was insensitive to proteinase K. After neuraminidase digestion, this inhibitory activity was lost. These data indicated that the inhibiting substance bore the typical features of gangliosides, which are multifunctional glycolipids that reside in cell membrane. Gangliosides were abundant in the CM from mesangial cells, as detected by metabolic radiolabeling and thin-layer chromatography (TLC). This result suggested that mesangial cells constitutively shed gangliosides. The growth suppressive activity in the CM was blunted when mesangial cells were pretreated with the ganglioside synthesis inhibitor d-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol-HCl (d-threo-PDMP; 20 micromol/L) in accordance with the decreased ganglioside content in cells. Finally, gangliosides isolated from CM of mesangial cells suppressed PDGF-induced DNA synthesis of mesangial cells. CONCLUSIONS: These results suggest that mesangial cells constitutively shed gangliosides that then suppress the division of these cells in an autocrine-like manner.

Animals↗
PubMed2001

Adaptive cytoprotection mediated by prostaglandin I(2) is attributable to sensitization of CRGP-containing sensory nerves.

BACKGROUND & AIMS: The phenomenon by which the gastric mucosa is protected in response to mild irritants has been called adaptive cytoprotection, a mechanism believed to be related to production of endogenous prostaglandins (PGs). We tested whether PGs generated by mild irritant prevent injury through the release of calcitonin gene-related peptide (CGRP) from the sensory nerves using prostanoid receptor-knockout mice. METHODS: The stomach was doubly cannulated and perfused with 1 mol/L NaCl or 50% ethanol. CGRP levels in the perfusate were determined by enzyme immunoassay, and the injured area was estimated at the end of perfusion. RESULTS: Preperfusion with mildly hypertonic saline (1 mol/L NaCl) increased generation of gastric PGE(2) and PGI(2) and reduced ethanol-induced mucosal damage. Exposure of ethanol after 1 mol/L NaCl increased intragastric CGRP levels from 166 +/- 27 to 713 +/- 55 pg/2 min (n = 4, P < 0.05), and the protective action of 1 mol/L NaCl was inhibited by indomethacin treatment. CGRP antagonist blocked 1 mol/L NaCl-induced protective effect. Intragastric perfusion of 50% ethanol after administration of PGI(2), but not of PGE(2), increased CGRP levels. Application of 1 mol/L NaCl to IP receptor-knockout mice (IP(-/-)) did not elicit the protective effects seen in the wild-type on ethanol-induced gastric mucosal lesions. Protective effect of 1 mol/L NaCl was observed in EP3 receptor-knockout mice (EP3(-/-)). CGRP level during ethanol perfusion was not increased in IP(-/-) but was increased in EP3(-/-) and wild-type counterparts after preperfusion of 1 mol/L NaCl. CONCLUSIONS: These results indicate that the endogenous PGI(2) generated by 1 mol/L NaCl may have a protective role in gastric mucosal injury through enhancement of CGRP release from gastric mucosa. This mechanism may explain the adaptive cytoprotection observed after treatment with mild irritants.

6-Ketoprostaglandin F1 alpha↗
PubMed2001

The dangers of snowboarding: a 9-year prospective comparison of snowboarding and skiing injuries.

We studied 2,552 snowboarding injuries and 5048 skiing injuries sustained during 1988-97. The number of snowboarding injuries had been increasing year by year and was 6 times as many as skiing injuries (2.0 versus 0.35 per 1,000 visits). The types of snowboarding injuries included fractures (39%), lacerations (21%), dislocations (17%), and contusions (15%). Upper extremity injuries were more frequent than those in the lower extremity in snowboarders. The commonest fractures involved the radius (48%), clavicle (11%), humerus (11%), and ulna (7-8%). The shoulder joint was most commonly dislocated (55%) followed by the elbow (27%), acromioclavicular (10%), finger (4%), and hip joints. In snowboarding accidents, the rates of fractures and dislocations were higher than those in skiing in almost every part of the body. Severe injuries were commoner in snowboarding accidents. We recommend the use of appropriate equipment and instructions for beginners to prevent such injuries.

Adolescent↗
PubMed2001

Mucinous adenocarcinoma of Bartholin gland treated with radiation therapy: a case report.

Adenocarcinoma of Bartholin gland is a very rare disease and its molecular pathological features are poorly delineated. A 92-year-old woman with mucinous adenocarcinoma of Bartholin gland with metastasis to the right inguinal lymph node was treated with radiation therapy alone. Despite intensive radiation therapy, the tumor was locally recurrent and the patient died 10 months after radiation therapy. We searched for the presence of human papillomavirus 16 and 18 DNA and the expression of p53 protein, CA19-9, CEA and MIB-1 antigen. Immunohistochemical study showed that mucinous adenocarcinoma of Bartholin gland produced CA19-9 and CEA.

Adenocarcinoma, Mucinous↗
PubMed2001

Mechanism of inhibitory effect of NCC164 on replication of human immunodeficiency virus.

The effect of a novel anti-HIV (human immunodeficiency virus) compound, designated NCC164, has been studied with HIV infected cultures. The agent exhibited concentration-dependent inhibition of HIV replication in primary infected cultures of H9 cell line and PBMCs. Substantial inhibition of viral replication was observed at concentration of NCC164 that showed little cytotoxicity. The ratio of IC50 values for the MTT (3-4,5 dimethylthiazol-2,5 diphenyl tetrazolium bromide) to RT (reverse transcriptase) assays means the selectivity index was more than 100. In attempting to define the inhibitory mechanism of NCC164, we investigated its effect on each step of HIV replication. This agent was highly effective against HIV replication regardless of the addition period during early stages of infection (adsorption to integration) but did not inhibit reverse transcriptase activity directly. The agent efficiently blocked virus maturation without side effect and the number of progeny produced by NCC164-treated cells was markedly reduced.

Adenosine↗
PubMed2001

Application of pressure-controlled colon delivery capsule to oral administration of glycyrrhizin in dogs.

A colon delivery system has been used to improve the bioavailability of glycyrrhizin, a glycoside of glycyrrhetic acid. The bioavailability of glycyrrhizin is low when administered in conventional oral galenic dosage forms because glycyrrhizin is enzymatically hydrolysed both in the stomach and in the intestine. It was reasoned that if large amounts of glycyrrhizin were directly delivered to the colon, enzymatic activity should be reduced due to saturation so that intact glycyrrhizin could be absorbed into the systemic circulation. Based on this assumption, pressure-controlled colon delivery capsules (PCDCs) were used as a colon delivery system. Eight types of glycyrrhizin solution were prepared and were introduced into PCDCs. After oral administration of the test PCDCs to beagle dogs, blood samples were obtained over 24 h and plasma glycyrrhizin concentrations were measured by an HPLC method. With PCDCs containing aqueous glycyrrhizin and propylene glycol solutions, plasma glycyrrhizin levels were extremely low and the bioavailabilities of glycyrrhizin were 0.6% and 0.4%, respectively. When Labrasol was added to both types of glycyrrhizin solution, the bioavailability was improved to 4.6% for aqueous solution and 3.8% for propylene glycol solution. When a surfactant, Polysorbate 80, was added in combination with Labrasol, synergistic effects were not obtained. Furthermore, dose-dependent effects of Polysorbate 80 were not obtained. Labrasol, which is a component of self-emulsifying drug delivery systems (SEDDS), has been shown to strongly improve the bioavailability of glycyrrhizin from the colon.

Administration, Oral↗
PubMed2001

Application of Eudragit P-4135F for the delivery of ellagic acid to the rat lower small intestine.

Based on the assumption that the delivery of ellagic acid to its site of action would show an antiinflammatory activity in inflammatory bowel disease (IBD), we have prepared microspheres using a new pH-sensitive polymer, Eudragit P-4135F (P-4135F), to deliver ellagic acid to the lower small intestine in rats. The microspheres were spherical in shape and the mean diameters were approximately 100-150 microm. The amount of ellagic acid released from the microspheres decreased by increasing the formulated amount of P-4135F. The release characteristics of ellagic acid were pH-dependent. By considering the factors loading efficiency and microsphere particle size distribution, ellagic acid-2 microspheres (P-4135F/ellagic acid = 1.65) were selected for further investigation. In a dissolution study, more than 95% ellagic acid was released within 0.5 h in pH 7.4 and 8.0 buffers. The release percent of ellagic acid was less than 40% in pH 6.8 and 7.0 and was less than 10% in pH 5.6 and 5.9. To observe the dissolution sites of the microspheres in the rat small intestine fluorescein was formulated in the microspheres as a tracer drug along with ellagic acid (50 mg kg(-1)). After intraduodenal administration of fluorescein-labelled microspheres to rats, the plasma fluorescein level started to increase at 0.5 h, by which time the microspheres had reached the middle part of the ileum. Microspheres started to dissolve within 1.0 h and the peak plasma fluorescein concentration was observed at 3.0 h, when the majority of the administered microspheres were dissolved in the terminal ileum. These results suggested that P-4135F microspheres could deliver ellagic acid to the lower part of the small intestine, and that the released ellagic acid would be distributed into the caecum and the ascending colon.

Administration, Oral↗
PubMed2001

Resting ultrasonic tissue characterization and dobutamine stress echocardiography for prediction of functional recovery in chronic left ventricular ischemic dysfunction.

This study was designed to assess the diagnostic accuracy of the percentage of resting systolic wall thickening (WT), dobutamine stress echocardiography (DSE), resting cyclic variation of integrated backscatter (IBS-CV), and low-dose dobutamine stress IBS-CV (DSE-IB) for the prediction of regional function recovery (RFR) in patients with chronic left ventricular (LV) ischemic dysfunction. The study also evaluated whether or not global LV function affected the diagnostic accuracy. All studies were conducted before percutaneous transluminal coronary angioplasty (PTCA) and RFR was assessed after PTCA (mean interval, 10 months) in 30 patients with chronic LV ischemic dysfunction. Patients were divided into 2 groups according to the LV ejection fraction (LVEF): group A, LVEF<40%, n=14; group B, LVEF> or =40%, n=16. Of a total of 480 segments, 37 initially demonstrating akinetic wall motion before PTCA were analyzed. The wall motion of 24 of the 37 segments improved on visual analysis after PTCA. In the prediction of RFR, resting WT, DSE, resting IBS-CV and DSE-IB had sensitivities of 79%, 79%, 92% and 62%, and specificities of 54%, 84%, 83% and 69%, respectively. In particular, the resting IBS-CV in group A, as well as DSE, was an excellent predictor of RFR (sensitivity, 100%; specificity, 86%; vs sensitivity, 82%; specificity, 78%; respectively). Therefore, both resting IBS-CV and DSE are useful predictors for RFR in patients with chronic LV ischemic dysfunction.

Aged↗