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H Ono

Publications and source records attributed to H Ono.

At least 109 records · Page 6Linked to original sources
PubMed2000

Molecular design of novel metal-binding oligomeric human metallothioneins.

Genes for dimeric and tetrameric human metallothionein (hMT) were designed and successfully overexpressed in Escherichia coli to generate functional oligomeric hMTs. An hMT synthesized with prokaryotic codons, a linker encoding a gly-gly-gly tripeptide, and Met-deficient hMT-II was ligated to create a dimeric hMT, from which a tetrameric hMT was then constructed. The increased molecular size of the constructs resulted in improved stability and productivity in E. coli. The oligomeric proteins formed inclusion bodies which were dissolved with dithiothreitol, and the purified apometallothioneins were reconstituted with Cd or Zn ions in a reducing condition. The oligomeric hMT proteins incubated with Cd ions showed a typical Cd-thiolate absorbance peak at 245-255 nm. The dimeric and tetrameric hMT proteins exhibited both Cd and Zn binding activities that were respectively two and four times higher than those of the hMT-II monomer protein. These novel oligomeric hMTs may be useful in bioremediation for heavy metals.

Amino Acid Sequence↗
PubMed2000

Plasma total glutathione concentrations in epileptic patients taking anticonvulsants.

Glutathione plays an important role in protecting cells against oxidative damage as a free radical scavenger. Since several anticonvulsants have been associated with decreased intrahepatic glutathione levels, we investigated plasma concentrations of total glutathione (including reduced and oxidized forms, tGSH=GSH+GSSG) in 45 epileptic patients taking anticonvulsant drugs. Plasma tGSH concentrations were significantly lower than in controls in patients treated with carbamazepine or phenytoin monotherapy, or with multiple drugs. Plasma tGSH concentrations in patients treated with valproic acid and in patients treated with phenobarbital did not differ significantly from those in controls. In no patient group was a significant correlation evident between duration of treatment or drug concentration and plasma tGSH concentration. No significant differences in plasma total cysteine concentrations were found between any patient group and controls. We conclude that some anticonvulsant drugs can lower plasma tGSH levels, reflecting treatment-related oxidative stress.

Adolescent↗
PubMed2000

Xenopus crescent encoding a Frizzled-like domain is expressed in the Spemann organizer and pronephros.

The Spemann organizer can be subdivided into head- and trunk-inducing tissues along the anteroposterior axis (Mangold, 1933. Naturwiisenschaften 43, 761-766; Spemann, 1931. Wilhelm Roux Arch. Entwicklungsmech. Org. 123, 389-517). Recent studies have suggested that head formation is brought about by repression of both Wnt and BMP signalling (Glinka et al., 1998. Nature 391, 357-362; Glinka et al., 1997. Nature 389, 517-519). Several Wnt inhibitors secreted from the head organizer region have been identified in Xenopus, such as Cerberus (Bouwmeester et al., 1996. Nature 382, 595-601), Frzb-1 (Leyns et al., 1997. Cell 88, 747-756; Lin et al., 1997. Proc. Natl. Acad. Sci. USA 94, 11196-11200), and Dkk-1 (Glinka et al., 1998. Nature 391, 357-362), supporting this two-inhibitor model. To isolate genes expressed in the head organizer, we screened a prechordal plate cDNA library by sequencing and expression pattern, and isolated the Xenopus ortholog of chick crescent encoding a Frizzled-like domain that is related to Wnt-binding regions of the Frizzled-family proteins. Expression of Xenopus crescent was first detected in the Spemann organizer region at the early gastrula stage and later in prechordal plate cells lining the boundary of mesoderm and ectoderm layers and in the anterior endoderm. At tailbud stages, the expression in the endomesoderm region was diminished, while expression in the pronephros became detectable. In animal cap assays, crescent gene was synergistically upregulated by coexpression of Xlim1, Ldb1, and Siamois, but not by Activin treatment.

Amino Acid Sequence↗
PubMed2000

Development of a host-vector system for Lactobacillus plantarum L137 isolated from a traditional fermented food produced in the Philippines.

Lactobacillus plantarum NC13, a strain derived from the L. plantarum strain L137 isolated from a traditional fermented food produced in the Philippines, contains 9 of the 15 plasmids in the parental strain. To construct a shuttle vector between L. plantarum and Escherichia coli for genetic manipulation of L137 and its derivatives, recombinant plasmids were prepared by using the 9-plasmid DNA mixture and an E. coli vector, pBluescript II SK+. The resultant recombinant plasmids were re-transferred to L. plantarum NCL21, an NC13-derived strain cured of 3 of the 9 plasmids, and 3 recombinant plasmids were obtained. The smallest plasmid, pRN14, contained a small cryptic plasmid, pLTK2, which is one of the plasmids in L. plantarum L137. Thus, the complete nucleotide sequence of pLTK2 was determined. The pLTK2 is 2295 bp in length, and has a major open reading frame of 951 bp. An encoded sequence of 317-amino acids showed extensive similarity with genes encoding replication protein (repA). A putative replication origin in pLTK2 also showed high homology to those of other gram-positive bacterial plasmids that replicate by the rolling circle mechanism. The shuttle vector pRN14 contained the erythromycin resistance gene and the ColE1 and pLTK2 replication origins. Transformation of L. plantarum strains with pRN14 by electroporation was optimized to give a transformation efficiency of 2 x 10(4) transformants/ mug plasmid. Plasmid pRN14 was stably maintained in strain NCL21, as well as in L. casei K95-5.

Journal Article↗
PubMed2000

Stem cell factor and/or endothelin-3 dependent immortal melanoblast and melanocyte populations derived from mouse neural crest cells.

Stem cell factor (SCF) and endothelin-3 (ET3) are both necessary for melanocyte development. In order to obtain immortal cell populations of melanoblasts that can survive without feeder cells, we first obtained an immortal cell population of neural crest cells (NCCs) from Sl/+ and +/+ mice of strain WB by incubating with a culture medium supplemented with SCF and ET3, and then we designated them as NCC-SE3 cells. NCC-SE3 cells were bipolar, polygonal, or round in shape and possessed melanosomes of stages I-III (mainly stage I). They were positive to dihydroxyphenylalanine (DOPA) reaction and expressed KIT (a receptor tyrosine kinase), tyrosinase, tyrosinase-related protein-1 (TRP1), tyrosinase-related protein-2 (TRP2), and endothelin-B receptor (ETRB) as determined by immunostaining. We next cultured NCC-SE3 cells by changing culture medium from the one supplemented with SCF + ET3 to the one supplemented with SCF or ET3. NCC-SE3 cells cultured with ET3 alone, designated as NCC-E3 cells, were bipolar in shape and had mainly stage II melanosomes and expressed the same proteins as did NCC-SE3 cells. However, NCC-SE3 cells cultured with SCF alone, designated as NCC-S4.1 cells, were polygonal in shape and had mainly stage I melanosomes. They are thought to be more immature because they were positive to KIT, TRP1, and TRP2, but not to ETR(B), tyrosinase, and DOPA reaction. When 12-O-tetradecanoylphorbol 13-acetate and cholera toxin were added to the culture medium, NCC-S4.1 cells changed shape from polygonal to bipolar and became DOPA-positive. This suggests that NCC-S4.1 cells are melanoblasts that have the potential to differentiate into melanocytes. These cell populations will be extremely useful to study factors that affect melanocyte development and melanogenesis.

Animals↗
PubMed2000

Delay of liver maturation as a cause of transient neonatal galactosemia.

BACKGROUND: Because a large amount of serum alpha-fetoprotein (alpha-FP) is synthesized in the liver of the fetus or premature newborn, high concentrations or delayed degradation of serum alpha-FP during the neonatal period may reflect hepatic immaturity. METHODS: In order to evaluate the relationship between transient neonatal galactosemia and delay of liver maturation, the concentration and half-life of serum alpha-FP during the neonatal period were measured in patients with transient galactosemia and in normal neonates. RESULTS: No significant differences were observed in the serum concentration of alpha-FP between normal and galactosemic patients less than 1 month of age. However, the half-life of serum alpha-FP was significantly longer in galactosemic patients between 15 and 60 days of age compared with age-matched normal neonates. CONCLUSION: Based on these results, we hypothesize that delay of liver maturation during the neonatal period, especially during the first 2 months after birth, can be a cause of transient neonatal galactosemia.

Galactose↗
PubMed2000

Transformation of the visual-line value in binocular vision: stimuli on corresponding points can be seen in two different directions.

We examined Wheatstone's (1838 Philosophical Transactions of the Royal Society of London 128 371-394) claim that images falling on retinally corresponding points can be seen in two different directions, in violation of Hering's law of identical visual direction. Our analyses showed that random-dot stereograms contain stimulus elements that are conceptually equivalent to the line stimuli in the stereogram from which Wheatstone made his claim. Our experiment demonstrated that two lines embedded in a random-dot stereogram appeared in two different directions when they stimulated retinally corresponding points, if the disparity gradient value of the lines was infinity relative to adjacent elements. To ensure that the two lines stimulated corresponding points, observers made vergence eye movements while maintaining the perception of the two lines in two different directions.

Convergence, Ocular↗
PubMed2000

Influence of corn oil and diet on reproduction and the kidney in female Sprague-Dawley rats.

The purpose of this study was to investigate the influence of corn oil administration on gestation, parturition, and lactation in rats, in conjunction with diets differing in composition of nutrients. Rats were divided into two groups, each fed different commercial pellets for rodents, CA-1 or CE-2, different from each other mainly in the source of protein. Female Sprague-Dawley rats in both diet groups were administered 0 (untreated control), 2, or 10 ml corn oil/kg body weight by gavage during the premating period (2 weeks), the mating period, the gestation period, and the lactation period (until day 3 of lactation). Food consumption of both the 10 ml/kg corn oil groups was significantly reduced throughout the study. Body weight gain in the 10 ml/kg corn oil group fed the CA-1 diet was significantly reduced on days 0 through 4 of lactation. Neither mating nor fertility indices were affected, and no clinical signs were observed during the gestation period in any groups. Several dams in the 10 ml/kg corn oil group fed the CA-1 diet, however, showed abnormal conditions after parturition, and three dams became moribund. Pup viability was also reduced in this group. Histopathologic examination of the kidneys of dams in the 10 ml/kg corn oil group fed the CA-1 diet revealed severe lesions in the proximal tubular epithelium, i.e., necrosis and fatty degeneration. Females in any group fed the CE-2 diet showed neither abnormal condition after parturition nor any severe lesions in the kidney. These data show that the combination of corn oil and diet with a particular constitution may cause adverse effects on the renal tubules in pregnant and/or lactating rats, suggesting that corn oil gavage as a vehicle can be a confounding factor in the reproductive toxicity studies, depending on the diet.

Animals↗
PubMed2000

Ectoine, the compatible solute of Halomonas elongata, confers hyperosmotic tolerance in cultured tobacco cells.

1,4,5,6-Tetrahydro-2-methyl-4-pyrimidinecarboxylic acid (ectoine) functions as a compatible osmolyte in the moderate halophile Halomonas elongata OUT30018. Ectoine is biosynthesized by three successive enzyme reactions from aspartic beta-semialdehyde. The genes encoding the enzymes involved in the biosynthesis, ectA, ectB, and ectC, encoding L-2,4-diaminobutyric acid acetyltransferase, L-2, 4-diaminobutyric acid transaminase, and L-ectoine synthase, respectively, have been previously cloned. To investigate the function of ectoine as a compatible solute in plant cells, the three genes were individually placed under the control of the cauliflower mosaic virus 35S promoter and introduced together into cultured tobacco (Nicotiana tabacum L.) cv Bright Yellow 2 (BY2) cells. The transgenic BY2 cells accumulated a small quantity of ectoine (14-79 nmol g(-1) fresh weight) and showed increased tolerance to hyperosmotic shock (900 mOsm). Furthermore, the transgenic BY2 cells exhibited a normal growth pattern even under hyperosmotic conditions (up to 530 mOsm), in which the growth of the untransformed BY2 (wild type) cells was obviously delayed. These results suggest that genetically engineered synthesis of ectoine results in the increased hyperosmotic tolerance of cultured tobacco BY2 cells despite the low level of accumulation of the solute.

Adaptation, Physiological↗
PubMed2000

Characterization of pRGO1, a plasmid from Propionibacterium acidipropionici, and its use for development of a host-vector system in propionibacteria.

The complete nucleotide sequence of pRGO1, a cryptic plasmid from Propionibacterium acidipropionici E214, was determined. pRGO1 is 6, 868 bp long, and its G+C content is 65.0%. Frame analysis of the sequence revealed six open reading frames, which were designated Orf1 to Orf6. The deduced amino acid sequences of Orf1 and Orf2 showed extensive similarities to an initiator of plasmid replication, the Rep protein, of various plasmids of gram-positive bacteria. The amino acid sequence of the putative translation product of orf3 exhibited a high degree of similarity to the amino acid sequences of DNA invertase in several bacteria. For the putative translation products of orf4, orf5, and orf6, on the other hand, no homologous sequences were found. The function of these open reading frames was studied by deletion analysis. A shuttle vector, pPK705, was constructed for shuttling between Escherichia coli and a Propionibacterium strain containing orf1 (repA), orf2 (repB), orf5, and orf6 from pRGO1, pUC18, and the hygromycin B-resistant gene as a drug marker. Shuttle vector pPK705 successfully transformed Propionibacterium freudenreichii subsp. shermanii IFO12426 by electroporation at an efficiency of 8 x 10(6) CFU/microg of DNA under optimized conditions. Transformation of various species of propionibacteria with pPK705 was also performed at efficiencies of about 10(4) to 10(7) CFU/microg of DNA. The vector was stably maintained in strains of P. freudenreichii subsp. shermanii, P. freudenreichii, P. pentosaceum, and P. freudenreichii subsp. freudenreichii grown under nonselective conditions. Successful manipulation of a host-vector system in propionibacteria should facilitate genetic studies and lead to creation of genes that are useful industrially.

Amino Acid Sequence↗
PubMed2000

Expression of CD44 variants and prognosis in oesophageal squamous cell carcinoma.

BACKGROUND: The CD44 variant (CD44v) isoforms have been noted as markers for tumour metastasis and prognosis in several adenocarcinomas. AIMS: To investigate whether CD44v, especially the CD44v2 (v2) isoform, may be a useful prognostic factor for patients with oesophageal squamous cell carcinoma, using a recently developed monoclonal antibody against a v2 epitope. PATIENTS: 233 patients (211 men and 22 women; mean age 61.9 years), with oesophageal squamous cell carcinomas curatively removed without additional treatment between 1987 and 1996 at the National Cancer Center Hospital, were analysed for CD44v expression. METHODS: The expression of CD44v was evaluated immunohistochemically using monoclonal antibodies against epitopes of the standard and variant protein, in paraffin embedded oesophageal squamous cell carcinoma tissue from 233 patients who had undergone cervical, mediastinal, and abdominal lymphadenectomy (three field dissection) for oesophagectomy. The data were evaluated for any correlation with clinicopathological indices or prognosis. RESULTS: Although total CD44 and CD44v6 (v6) were respectively observed in 99% and 97% of the cancer specimens, the expression of v2 was only 30%. Patients whose tumours were v2 positive had a significantly better prognosis than those whose tumours were v2 negative (p = 0.031). Furthermore, in patients without lymph node metastasis, v2 positivity alone was a significant independent factor of prognosis (relative risk of death associated with v2 negativity, 4.7; p = 0.037) in multivariate analysis. CONCLUSIONS: These results indicate that v2 is a useful marker for clinical prognosis in patients with oesophageal squamous cell carcinoma. Particularly in patients without lymph node metastasis, v2 status may thus have implications for the use of adjuvant chemotherapy and/or radiotherapy in patients with oesophageal cancer at an early stage.

Adult↗
PubMed2000

Fracture of hamate hook--diagnosis by the hamate hook lateral view.

Ten intact wrist joints were examined to evaluate the hamate hook visualisation by a hamate hook lateral radiographic view. Results of the study indicated that this 30 degrees -tilted lateral wrist radiographic projection with palmar abduction of the thumb clearly revealed the hamate hook from its base to the tip in the first web space away from the metacarpal bases and carpal bones. This radiographic technique was applied on patients who experienced pain at the hypothenar eminence. Fracture can be detected at the hamate hook in two cases and bilateral bipartite hamulus in one case. This specific supplementary projection is recommended in patients with the relevant physical signs.

Adolescent↗
PubMed2000

Phlebosclerotic colitis: value of radiography in diagnosis--report of three cases.

Three cases sharing the following radiologic features are reported: (a) abdominal conventional radiography-vascular calcifications at the right hemicolon, (b) abdominal computed tomography-colonic wall thickening and venous calcifications, and (c) barium enema examination-luminal narrowing of the right hemicolon and thumbprinting. There were no clinical or laboratory findings suggestive of portal hypertension. The disease entity, "phlebosclerotic colitis," should be differentiated from ordinary ischemic colitis.

Abdomen, Acute↗
PubMed2000

Mitotic index is the best predictive factor for survival of patients with resected hepatocellular carcinoma.

BACKGROUND: In patients with hepatocellular carcinoma (HCC), tumor recurrence is not infrequent after resection. It is presumed that characteristics of the tumor such as cellular malignancy might influence the prognosis of the patients in association with tumor stage and radicality of the procedure. METHODS: Univariate and multivariate analyses were used to retrospectively determine the clinicopathologic factors potentially related to survival in 40 patients who underwent hepatectomy for HCC. RESULTS: In univariate analysis, tumor stage I or II, mitotic index of 4 or less/10 random high-power fields, solitary tumor, and curative resection were significantly correlated with better survival. In multivariate analysis, the mitotic index and surgical curability were independently significant variables influencing survival of patients, and the mitotic index was the best predictive factor. A highly significant correlation was found between the mitotic index and Ki-67 labeling index. Compared to tumors with a mitotic index of 4 or less, those with a mitotic index of 5 or more had a higher association with multiple tumors and advanced tumor stage, which preclude curative resection. CONCLUSION: Analysis of the mitotic index is quite simple, and the mitotic index could be a useful factor for predicting the long-term survival of patients with HCC following hepatic resection.

Carcinoma, Hepatocellular↗
PubMed2000

Hepatectomy using an ultrasonically activated scalpel for hepatocellular carcinoma.

BACKGROUND: The first retrospective studies were performed to compare the efficacy of the ultrasonic cavitational aspirator (aspirator group) and the ultrasonically activated scalpel (scalpel group) for hepatic resection in patients with hepatocellular carcinoma. PATIENTS AND METHODS: The aspirator group consisted of 8 patients (6 with liver cirrhosis and 2 with chronic hepatitis in the nontumorous liver), and the scalpel group of 7 patients (6 with liver cirrhosis and 1 with chronic hepatitis). All patients underwent limited hepatic resection, and the intermittent Pringle maneuver was applied during hepatic transection. RESULTS: There were no significant differences in preoperative hepatic function, type of hepatectomy, tumor size and maximum cross-sectional area of the resected specimen between the 2 groups. The amount of intraoperative blood loss was significantly less in the scalpel group than in the aspirator group (684 versus 1,859 ml, p < 0.05). The operation time was significanly shorter in the scalpel group than in the aspirator group (176 versus 262 min, p < 0.05). There were no significant differences in postoperative liver function and morbidity between the 2 groups. CONCLUSIONS: The ultrasonically activated scalpel is effective in reducing blood loss and in shortening the time of operation, and can be employed during limited resection of the liver with cirrhosis or chronic hepatitis.

Aged↗