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H Ohno

Publications and source records attributed to H Ohno.

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

Superoxide dismutase gene expression is activated by a single bout of exercise in rat skeletal muscle.

The goal of this experiment was to examine contraction-mediated activation of superoxide dismutase (SOD) gene expression in rat superficial vastus lateralis (SVL, type IIb) and deep vastus lateralis (DVL, type IIa) muscles. Female Sprague-Dawley rats were randomly divided into exercise (E) and control (C) groups that were sacrificed at 0, 1, 2, 4, 10, 24, and 48 h (n=6) following an acute bout of treadmill exercise (25 m/min, 5% grade) to exhaustion (running time approximately equals 1 h). Nuclear factor-kappaB (NF-kappaB) in DVL and SVL showed maximal binding at 2 and 10 h respectively, and remained elevated. Activator protein-1 (AP-1) showed maximal binding at 1 h post-exercise, and returned to resting levels at 10 h in both muscles. Mn SOD mRNA abundance in the DVL was increased at 0 (P<0.01), 1, and 2 h (P<0.05) post-exercise, whereas Mn SOD protein was unchanged. In SVL, Mn SOD mRNA abundance was not altered by exercise, whereas Mn SOD protein content was increased at 10 (P<0.05) and 24 h (P<0.075) post-exercise. CuZn SOD mRNA was unchanged with exercise in DVL and SVL, but CuZn SOD protein was elevated 48 h after exercise in both DVL and SVL (P<0.01). Activities of Mn SOD, CuZn SOD and total SOD showed no change with exercise in either muscle examined. These findings indicate that an acute bout of exercise can increase binding of NF-kappaB and AP-1 in both SVL and DVL, which may stimulate Mn SOD mRNA transcription in the more oxidative type DVL muscle. The increased CuZn SOD protein contents seen post-exercise, without increases in mRNA abundance in both DVL and SVL, suggest a translational mechanism in this SOD isoform.

Animals↗
PubMed2001

Occurrence of organo-arsenicals in jellyfishes and their mucus.

Water-soluble arsenic compound fractions were extracted from seven species of jellyfishes and subjected to analysis by high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS) for arsenicals. A low content of arsenic was found to be the characteristic of jellyfish. Arsenobetaine (AB) was the major arsenic compound without exception in the tissues of the jellyfish species and mucus-blobs collected from some of them. Although the arsenic content in Beroe cucumis, which preys on Bolinopsis mikado, was more than 13 times that in B. mikado, the chromatograms of these two species were similar in the distribution pattern of arsenicals. The nine species of jellyfishes including two species treated in the previous paper can be classified into arsenocholine (AC)-rich and AC-poor species. Jellyfishes belonging to Semaostamae were classified as AC-rich species.

Animals↗
PubMed2001

Mercury pollution in the Tapajos River basin, Amazon: mercury level of head hair and health effects.

There is increasing concern about the potential neurotoxic effects of exposure to methylmercury for the 6 million people living in the Amazon, even in regions situated far away from the gold mines (garimpos), considered to be the major source of mercury pollution. In November 1998, a spot investigation on mercury contamination was conducted in three fishing villages (Barreiras, Rainha, and Sao Luiz do Tapajos) on the Tapajos River, an effluent of the Amazon, situated several hundred kilometers downstream from the gold-mining areas. A total of 132 fishermen and their families volunteered for the current study. As was anticipated, the total mercury levels in the head hair collected from the fishing villages were relatively high (14.1-20.8 ppm on the average) and the number of subjects with a high total mercury level over 10 ppm (the least upper bound of a normal value) was 103 (78.0%) in total, along with various symptoms, thereby suggesting wide mercury contamination in the Tapajos River basin. Moreover, in view of the absence of other diseases (e.g., alcoholism or malaria), a high intake of fish containing a methylmercury level, and high hair mercury levels in addition to the various symptoms such as sensory disturbance (especially glove-and-stocking type, which is characteristic of Minamata disease), tremor, failure in two-point discrimination, and slight balancing failure, several subjects examined were diagnosed with mild Minamata disease. The findings obtained suggest, thus, that the mercury pollution in the Amazon should be crucially observed for head hair mercury level and health in a much broader region.

Adolescent↗
PubMed2001

Cloning and characterization of the 5'-flanking region of human cytokeratin 19 gene in human cholangiocarcinoma cell line.

BACKGROUND/AIMS: The regulatory mechanism of cell-specific gene expression in cholangiocytes has not been sufficiently evaluated. In this study, we characterized the 5'-flanking region of the cytokeratin 19 gene expressed specifically in cholangiocytes. METHODS: We cloned a 2952-bp fragment in the 5'-flanking region of cytokeratin 19 and evaluated the regulatory mechanism of gene expression in this region by assaying transient expression of reporter gene and DNA footprinting. RESULTS: This segment of the 5'-flanking region of the human cytokeratin 19 gene shows an intense transcriptional activity in the cholangioma cell line KMBC, which was about 10 times its activity in the osteosarcoma cell line Saos-2, which does not express cytokeratin 19. From the results of reporter assays, important transcription regulatory elements are considered to be located in the segments from -2249 to -2050 bp and from -732 bp to the first ATG, and six protein-binding sites were detected in the segment from -732 bp to the first ATG by the DNA footprinting technique. CONCLUSIONS: Sp1 site, CCAAT box, and TATA box were present in the segment from -374 to the first ATG, and they are considered to constitute a cholangiocyte-specific promoter.

Base Sequence↗
PubMed2001

Single bout of exercise eliminates the immobilization-induced oxidative stress in rat brain.

We were interested in the effects of immobilization (IM), a single bout of exercise (E) and immobilization followed by exercise (EIM) on memory and oxidative damage of macromolecules in hippocampus of rat brain. Eight hours of IM resulted in impairment of passive avoidance test (memory retrieval deficit) and increased latency to start locomotion in an open-field test. Two hours of swimming did not significantly alter the memory retrieval deficit and latency, while the EIM group had longer latency and similar memory than control and E groups. The oxidative damage of lipids, proteins and nuclear DNA increased significantly in IM group and no increase was observed in E and EIM animals. The activity of proteasome was not altered in any groups. The activity of glutamine synthetase (GS) was decreased in IM group (P < 0.05), this down regulation was not observed in E and EIM groups. These data suggest that oxidative damage of macromolecules is associated with impaired cognitive function. Single bout of exercise after immobilization eliminates the oxidative damage of macromolecules and normalizes memory function, probably by its ability to restore the activity level of GS and eliminate the consequences of immobilization-induced prolonged efflux of glutamate.

Animals↗
PubMed2001

Characteristics of plasma extracellular SOD in burned patients.

The aim of this study was to examine three types of superoxide dismutase (SOD) in plasma after burns, and especially to clarify the characteristics of plasma extracellular SOD (EC-SOD) in burned patients. A total of 71 blood samples were collected from 18 patients on arrival, day 1, day 3 and day 5 after burns. We measured three types of SOD (Mn, Cu/Zn, EC) in plasma using ELISA, and the relationships among the three types of SOD concentrations were examined. We next analyzed the characteristics of plasma EC-SOD using stepwise multivariate regression analysis. Any plasma SOD isoenzyme concentration measured after burns was beyond the normal range and EC-SOD accounted for the major part of plasma SODs. EC-SOD and Cu/Zn-SOD were positively correlated, whereas Mn-SOD was not related to the other SODs. Also, plasma EC-SOD was significantly related to existence of inhalation injury, %TBSA and age, respectively. The plasma EC-SOD might therefore play some roles in the pathophysiology of burned patients.

Adult↗
PubMed2001

Heterogeneous breakpoints on the immunoglobulin genes are involved in fusion with the 5' region of BCL2 in B-cell tumors.

The 5' flanking region of the BCL2 gene (5'-BCL2) is a breakpoint cluster of rearrangements with immunoglobulin genes (IGs). In contrast to t(14;18)(q32;q21) affecting the 3' region of BCL2, 5'-BCL2 can fuse to not only the heavy chain gene (IGH), but also two light chain gene (IGL) loci. We report here cloning and sequencing of a total of eleven 5'-BCL2 / IGs junctional areas of B-cell tumors, which were amplified by long-distance polymerase chain reaction-based assays. The breakpoints on 5'-BCL2 were distributed from 378 to 2312 bp upstream of the translational initiation site and, reflecting the alteration of regulatory sequences of BCL2, 5'-BCL2 / IGs-positive cells showed markedly higher levels of BCL2 expression than those of t(14;18)-positive cells. In contrast, the breakpoints on the IGs were variable. Two 5'-BCL2 / IGH and two 5'-BCL2 / IGLkappa junctions occurred 5' of the joining (J) segments, suggesting operation of an erroneous variable (V) / diversity (D) / J and V / J rearrangement mechanism. However, two other 5'-BCL2 / IGH junctions affected switch regions, and the kappa-deleting element, which is located 24 kb downstream of the constant region of IGLkappa, followed the 5'-BCL2 in another case. One 5'-BCL2 / IGLkappa and two 5'-BCL2 / IGLlambda junctions involved intronic regions where the normal recombination process does not occur. In the remaining one case, the 5'-BCL2 fused 3' of a Vlambda gene that was upstream of another Vlambda / Jlambda complex carrying a non-producing configuration, indicating that the receptor editing mechanism was likely involved in this rearrangement. Our study revealed heterogeneous anatomy of the 5'-BCL2 / IGs fusion gene leading to transcriptional activation of BCL2, and suggested that the mechanisms underlying the formation of this particular oncogene / IGs recombination are not identical to those of t(14;18).

Base Sequence↗
PubMed2001

Telomerase activity is not altered by regular strenuous exercise in skeletal muscle or by sarcoma in liver of rats.

Telomerase is a specialized ribonucleoprotein enzyme complex which prevents the loss of the telomere. The activity of telomerase can be up- and down-regulated by various oxidative stresses but the effect of physical exercise is not known, whereas the modifying effect of cancer on telomerase activity is well documented. In the first study, we investigated the effect of mild and strenuous exercise training on telomerase activity, assessed by a PCR ELISA kit. No alteration in telomerase activity was detected. In the second investigation, solid sarcoma cells were transplanted to control, exercise trained or exercise trained and still exercising mice. On the 16th day after the transplantation, the size of tumors in the exercise trained group was 72% and in the exercising group 57% (P < 0.05) of that in the controls. Telomerase activity and 8-hydroxy-2'-deoxyguanosine levels in the liver were not significantly altered by exercise and/or sarcoma. We conclude that mild and strenuous exercise training does not significantly affect the activity of telomerase in the systems studied. Exercise training during sarcoma significantly retards the development of tumors and could possibly serve as a positive adjunct to treatment.

8-Hydroxy-2'-Deoxyguanosine↗
PubMed2001

Direct targeting of cis-Golgi matrix proteins to the Golgi apparatus.

The targeting route of newly synthesized GM130 and GRASP65 to the Golgi apparatus was investigated by three different approaches. First, localization of pulse labeled GM130 and GRASP65 in normal rat kidney (NRK) cells was traced by subcellular fractionation followed by immunoprecipitation. Immediately after the pulse labeling, GM130 and GRASP65 were found in the Golgi but not in the endoplasmic reticulum (ER) membrane fractions, whereas a control Golgi membrane protein was still found in the ER membrane fractions. Second, epitope tagged GM130 and GRASP65 were expressed in NRK cells by plasmid microinjection into the nuclei and their localization was analyzed by immunofluorescence. When ER to Golgi transport was inhibited by prior microinjection of a GTP-restricted mutant of Sar1 protein into the cytosol, the expressed GM130 and GRASP65 showed clear Golgi localization. Last, binding of GM130 and GRASP65 to the membranes was analyzed in vitro. In vitro synthesized GM130 and GRASP65 specifically bound to purified Golgi membranes but not to microsomal membranes. The bound GM130 and GRASP65 were found to form a complex with pre-existing counterparts on the Golgi membrane. These results strongly suggested that GM130 and GRASP65 are directly targeted to the Golgi membrane without initial assembly on the ER and subsequent vesicular transport to the Golgi apparatus.

Animals↗
PubMed2001

[Development of aziridination and azetizination reactions of amino allenes using a palladium catalyst].

Palladium-catalyzed synthesis of alkenylaziridines and azetidines from alpha- and beta-amino allenes are presented. Whereas palladium-catalyzed reaction of N-arylsulfonyl-alpha-amino allenes with an aryl iodide in the presence of potassium carbonate in DMF at around 70 degrees C affords the corresponding 3-pyrroline derivatives, the reaction in refluxing 1,4-dioxane under similar conditions yields exclusively or most predominantly the corresponding 2-alkenylaziridines bearing an aryl group on the double bond. Similarly, N-arylsulfonyl-beta-amino allenes can be also cyclized into the corresponding alkenylazetidines bearing 2,4-cis-sunstituents under palladium-catalyzed cyclization conditions in DMF.

Alkadienes↗
PubMed2001

Changes in the tissue and plasma superoxide dismutase (SOD) levels in a burned rat model.

To examine whether thermal injury alters the superoxide dismutase (SOD) concentrations in various types of tissue or plasma, we studied the plasma and tissue Mn- and Cu/Zn-SOD levels in a rodent burn model. The animals were resuscitated with saline (50 mg/kg, i.p.) immediately following thermal injury and thereafter were sacrificed at either 6 or 24 hours post-burn. The Mn- and Cu/Zn-SOD levels were measured using an enzyme-linked immunosorbent assay (ELISA). The plasma Mn- and Cu/Zn-SOD concentrations significantly increased 6 hours after the injury and positively correlated with the burn size. The kidney Mn-SOD concentrations were significantly higher 24 hours after the injury in the animals with 30% burns than in those with either sham or 50% burn injuries. The lung Cu/Zn-SOD concentrations were also significantly higher 6 hours after the injury in animals with 30% burns than in the other two types above. These findings suggest that the changes in the SOD concentrations after burn injury vary according to the type of SOD and also the type of tissue. As a result, the SOD concentrations may play some role in the early response to thermal trauma.

Animals↗
PubMed2001

Corrosion behavior and surface structure of orthodontic Ni-Ti alloy wires.

The corrosion behaviors of a commercial Ni-Ti alloy orthodontic wire and a polished plate with same composition in 0.9% NaCl and 1% lactic acid solutions were examined using an electrochemical technique, an analysis of released ions, and a surface analysis by X-ray photoelectron spectroscopy (XPS). The effect of polishing the wire on the corrosion was also examined. The XPS analysis demonstrated the presence of a thick oxide film mainly composed of TiO2 with trace amounts of Ni hydroxide, which had formed on the wire surface during the heat treatment and subsequent pickling processes. This oxide layer contributed to the higher resistance of the as-received wire to both general and localized corrosion in 0.9% NaCl solution, compared with that of the polished plate and the polished wire. The thick oxide layer, however, was not stable and did not protect the orthodontic wire from corrosion in 0.1% lactic acid solution.

Corrosion↗
PubMed2001

Mechanism of adhesion between 4-META resin and alloys based on Bolger's acid-base interaction.

The water durability at adhesion interfaces between 4-META resin and Au-In or Au-Si alloys was investigated by the peeling test and by surface analysis using X-ray photoelectron spectroscopy (XPS) as well as theoretical consideration based on Bolger's acid-base theory. XPS spectra demonstrated that several-nm thick layers of In2O3 and SiO2 were formed on the Au-In and Au-Si alloys. The water durability of the Au-In alloys increased with increases in In content. The Au-Si alloy and quartz glass specimens showed a total absence of water durability. Bolger's theory suggested that the interaction of 4-MET with In2O3 was considered to be ionic and stable in the presence of water while that of 4-MET with SiO2 was due to hydrogen bonds, which can easily be dissociated in the presence of water. These findings suggest that Bolger's theory is useful for evaluating chemical interactions between an adhesive monomer and oxides on a precious metal alloy.

Acrylic Resins↗
PubMed2001

XPS study on the weakest zone in the adhesion structure between resin containing 4-META and precious metal alloys treated with different surface modification methods.

Three precious metal alloys, Type IV gold alloy, 14 K gold alloy, and silver-based alloy, were treated with different surface modifications including a metal primer (VBATDT) application, a SiOx coating method, high-temperature oxidation, modification method with a liquid Ga-Sn alloy, and tin electroplating. Then thin PMMA films were bonded with a resin containing 4-META. Water durability at the adhesion interface was evaluated after water immersion, followed by thermal cycling used liquid nitrogen. The weakest zone at the interface was investigated using XPS only for the Ag-Pd alloy specimens that had been surface-treated with as-polishing, adhesive primer, and the SiOx coating method, since peeling of the PMMA film on the surface of specimens surface-treated by other methods was not observed. Metal elements were detected from the resin side at the adhesion interface. The chemical states of Cu in the resin before argon ion etching were characterized as metal oxides and/or states of chemical interaction with 4-META, VBATDT, or SiOx.

Acrylic Resins↗
PubMed2001

[Laparoscopy-assisted total nephroureterectomy for renal pelvic and/or lower ureteral cancer].

PURPOSE: The usefulness of laparoscopy-assisted total nephroureterectomy for patients with renal pelvic and lower ureteral cancer is evaluated. MATERIAL: Seven patients with renal pelvic cancer and four with lower ureteral cancer performed laparoscopy-assisted total nephroureterectomy from May 1997 to December 2000 (Ten males and one female, mean age 68.5 year-old). METHOD: Of the 11 patients, the initial one received preoperative embolization of the renal artery. Under general anesthesia laparoscopy-assisted total nephroureterectomy underwent via transperitoneal approach in three patients and retroperitoneal approach in eight. After the kidney was completely dissected under laparoscopic procedure, it was delivered en bloc with ureter from the skin incision in the lower abdomen. RESULT: Two patients needed conversion to open surgery. The mean operating time of nine patients except for conversion cases was 272 minutes and the mean blood loss was 313 ml. There was no major complication associated with laparoscopic procedure. There was no significant difference in both complication and recurrence rate between laparoscopy-assisted total nephroureterectomy and open surgery. CONCLUSION: Laparoscopy-assisted total nephroureterectomy is an useful procedure for the treatment of patients with renal pelvic and lower ureteral cancer because it enables us to remove out the kidney and ureter from one small lower abdominal incision.

Aged↗
PubMed2001

[High-dose therapy and peripheral blood stem cell transplantation for patients with aggressive non-Hodgkin's lymphoma remaining in initial remission: results of a feasibility study].

High-dose therapy with peripheral blood stem cell transplantation (HDT/PBSCT) was performed as one aspect of front-line therapy in patients with poor-risk aggressive non-Hodgkin's lymphoma (high-intermediate/high risk) according to the age-adjusted international prognostic index (aaIPI). Twenty-nine patients were enrolled in this study between November 1994 and March 1999. CHOP + etoposide (CHOP-E) was used as an initial chemotherapy and as a chemotherapy agent for the purpose of cell harvesting. Peripheral blood stem cells were harvested from 17 patients, and HDT with CEC (carboplatin, etoposide, cyclophosphamide)/PBSCT was performed in 11 patients. Eighteen patients dropped out, including five for whom CHOP-E therapy was ineffective and 5 who did not give consent for cell harvesting or HDT/PBSCT. CHOP-E therapy produced complete remission (CR) in 15 out of 26 patients (58%) after discounting the 3 who were ineligible among the 29 who were initially enrolled. The median observation period after PBSCT in the 11 patients who underwent HDT/PBSCT was 25 months (3 to 50 months), and the 3-year disease-free survival rate was 73%. No serious complications associated with the transplantation were observed. We were able to confirm the feasibility and safety of HDT/PBSCT as one form of front-line therapy for aggressive non-Hodgkin's lymphoma in patients under 60 years of age.

Adolescent↗
PubMed2001

Adaptation to exercise-induced oxidative stress: from muscle to brain.

Exercise increases the generation of reactive oxygen and nitrogen species (RONS) and by causing adaptation, could decrease the incidence of RONS-associated diseases. A single bout of exercise, depending upon intensity and duration, can cause an increase in antioxidant enzyme activity, decrease levels of thiols and antioxidant vitamins, and result in oxidative damage as a sign of incomplete adaptation. Increased levels of RONS and oxidative damage are initiators of a specific adaptive response, such as the stimulation of the activation of antioxidant enzymes, thiols, and enhanced oxidative damage repair. Regular exercise has the capability to develop compensation to oxidative stress, resulting in overcompensation against the increased level of RONS production and oxidative damage. Regular exercise causes adaptation of the antioxidant and repair systems, which could result in a decreased base level of oxidative damage and increased resistance to oxidative stress.

Adaptation, Biological↗