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Y Harada

Publications and source records attributed to Y Harada.

At least 325 records · Page 18Linked to original sources
PubMed1995

Effect of lipopolysaccharide on thymidine salvage as related to macrophage activation.

Lipopolysaccharide (LPS), known as one of the potent activators of macrophages, has inhibitory effects on the proliferation of normal macrophages and macrophage-like cell lines. We report here that LPS dose- and time-dependently suppressed the tritiated thymidine ([3H]TdR) incorporation into the acid-insoluble fraction with a significant inverse correlation to the tumour necrosis factor-alpha (TNF) production in the J774.1 macrophage cell line. Among the three tested enzymes involved in DNA synthesis, only thymidine kinase (TK) activity decreased progressively in parallel with the decline in [3H]TdR incorporation, reaching 97% inhibition within 12 hr of LPS treatment, while changes in the activities of other two enzymes, DNA polymerase alpha and thymidylate synthase (TS), were less significant. On the other hand, LPS inhibited the cell proliferation only incompletely, as judged by 62% inhibition of cell growth at 36 hr. Even in the experiments done in a TdR-free medium, cell growth was inhibited by LPS to the same extent, suggesting that TK was not directly involved in the proliferation of J774 cells. LPS also inhibited the conversion of TdR to thymidine monophosphate (TMP) in murine peritoneal exudate macrophages (PEM). Thus LPS-induced suppression of TdR salvage related to TNF production is common in both normal and neoplastic macrophages, and therefore may be of potential importance in the process of macrophage activation.

Animals↗
PubMed1995

[A case of remarkable response of colon cancer with multiple liver and bone metastasis treated with tegafur and cisplatin].

A 47-year-old man with ascending colon cancer with multiple liver metastases and bone metastasis (VII thoracic vertebra) showed a remarkable response to the combination therapy of tegafur and cisplatin. Tegafur (1,200 mg/day) was administered through continuous intravenous infusion mixed with IVH, and cisplatin was given every two weeks at a dose of 100 mg. The total dose of tegafur was 39.6g and that of cisplatin was 300mg. After therapy, primary and metastatic lesions were remarkably reduced according to various imaging techniques, and the serum CEA level of 34ng/ml at diagnosis decreased 3.7 ng/ml. Various tumor-related symptoms were improved. Drug toxicity caused slight nausea and leucopenia. Right hemicolectomy with R2 lymph node dissection was performed after chemotherapy. Histologically, primary lesion and regional lymph nodes showed diffuse fibrosis and necrosis, and only a few cancer cells remained some vessels. These results suggested that the combination chemotherapy of tegafur and cisplatin is useful for the treatment of colon cancer.

Adenocarcinoma↗
PubMed1995

[Two cases of gross E-type tracheo-esophageal fistulae associated with interruption of the aortic arch and coarctation of the aorta in early infancy].

Two cases of Gross E-type tracheoesophageal fistulae associated with interruption of the aortic arch in one and coarctation of the aorta in the other in early infancy were treated radically at Nagano Children's Hospital during the preceding 4 months until January 1994. The tracheoesophageal fistulae were noticed after the first stage surgery for the aortic arch anomalies, because of the remarkable abdominal distension under the intubated and ventilated condition of general anesthesia. Both the bronchial and esophageal optical fiber examinations were performed which proved useful to detect the fistulae. In each case, the transcervical division of the fistula was performed on an emergency basis. The external diameter of the fistula was 4 and 5 mm respectively. The fistulae dilated synchronously with ventilation. The early detection and surgical correction of the tracheoesophageal fistula can prevent serious complications such as DIC as seen in the first case probably caused by respiratory infection associated with the prolonged mechanical ventilation. Successful intracardiac repair were performed in both cases on the 25th and 7th day following the correction of the fistulae respectively.

Aorta, Thoracic↗
PubMed1995

Characterization of a cDNA clone encoding 23 kDa polypeptide of the oxygen-evolving complex of photosystem II in rice.

We isolated a cDNA for a gene that encodes the 23 kDa protein of the oxygen-evolving complex of photosystem II in rice. The amino acid sequence deduced from the cDNA is highly similar (71-60% homology) to those of the analogous genes from wheat, tomato, pea, spinach, tobacco and mustard. The expression of the gene that corresponds to the 23 kDa protein was inducible in green organs of mature and immature leaves, stems and young panicles but not inducible in roots. The high level of the transcripts was detected in both mature leaves and young panicles. The expression of the gene was low in etiolated seedlings, while the transcript of the gene was strongly induced by light, and the level of the expression increased during light irradiation. These observations suggest that the expression of the gene encoding the 23 kDa protein is organ-specific and light-inducible.

Amino Acid Sequence↗
PubMed1995

[A case of one stage-repair of interrupted aortic arch and ventricular septal defect in neonate using a separated cardiopulmonary bypass].

We report a case of one stage-repair of interrupted aortic arch and ventricular septal defect in neonate. The operation was performed at the age of 14 days. After a median sternotomy incision, a separated cardiopulmonary bypass was commenced through the ductus and a 4 mm EPTFE graft which was anastomoted to the right subclavian artery. Cerebral circulation was maintained through the graft during reconstruction of the aortic arch. Our method is useful regarding that brain damage can be avoided which may be induced by total circulatory arrest.

Aorta, Thoracic↗
PubMed1994

Genetic studies of 457 breast cancers. Clinicopathologic parameters compared with genetic alterations.

BACKGROUND: Human breast cancers frequently show loss of heterozygosity (LOH) and/or amplification at specific chromosomal regions. METHODS: To investigate the roles of these genetic alterations during tumor development and/or progression, 457 cases of primary breast cancer were examined for LOH at chromosomal regions 16q24, 17p13.3, and 17q21, and for amplification of the erb-B2 locus at 17q11.2 and the c-myc locus at 8q24. The genetic changes then were compared with lymph node metastasis, histologic type, and tumor stage. RESULTS: The LOH at 17q21 was observed more frequently in tumors of the solid, tubular type (41 of 75 [55%]) than in other types (48 of 187 [26%]) (P < 0.0001). The LOH at 17p13.3 was more frequent in scirrhous and solid, tubular tumors (77 of 141 [55%] and 48 of 88 [55%]) than in other types (29 of 89 [33%]) (P = 0.0004). Generally, mutations were seen more often in tumors with axillary lymph node metastases, undifferentiated tumors, and large or invasive tumors than in tumors considered less aggressive histopathologically. However, 22 tumors bearing three or more genetic alterations were found among 187 tumors histologically diagnosed as free of axillary lymph node metastasis; similarly, 12 of 122 t1 classification tumors and 4 of 89 histologically well differentiated tumors each contained three or more genetic alterations. Although these tumors would be regarded as having a relatively good prognosis on the basis of conventional clinicopathologic diagnosis, the authors suspect that, in fact, they do not. CONCLUSIONS: Patients whose tumors contain multiple genetic alterations should be treated as a new high risk group with respect to operative and/or postoperative management.

Blotting, Southern↗
PubMed1994

Binding properties of KB-5492, a novel anti-ulcer agent, at sigma receptors in porcine gastric fundic mucosa.

We examined the effects of KB-5492, 4-methoxyphenyl 4-(3,4,5-trimethoxybenzyl)-1-piperazine acetate monofumarate monohydrate, a novel anti-ulcer agent and a selective sigma receptor ligand, on specific [3H](+)-N-allyl-normetazocine (SKF 10,047) and [3H]1,3-di(2-tolyl)guanidine (DTG) binding in porcine gastric fundic mucosa. KB-5492 inhibited specific [3H](+)-SKF 10,047 binding in a competitive manner and specific [3H]DTG binding in a non-competitive manner. The Ki value of KB-5492 on specific [3H]DTG binding (Ki = 4.6 microM) was 8.4-fold higher than that on specific [3H](+)-SKF 10,047 binding (Ki = 0.55 microM). Computer-assisted analysis of the displacement curve of KB-5492 for specific [3H]DTG binding indicated the best fit for a two-site model rather than a one-site model, but not for specific [3H](+)-SKF 10,047 binding. Anti-ulcer agents such as omeprazole, cetraxate, cimetidine, sofalcone, sucralfate, teprenone and troxipide had weak or little effect on specific [3H](+)-SKF 10,047 and [3H]DTG binding at a concentration of 100 microM, except that omeprazole exhibited a low affinity for specific [3H](+)-SKF 10,047 binding. These findings suggest that KB-5492 is a unique anti-ulcer agent which binds to sigma receptors in porcine gastric fundic mucosa.

Animals↗
PubMed1994

Receptor binding profiles of KB-5492, a novel anti-ulcer agent, at sigma receptors in guinea-pig brain.

We studied the receptor binding profile of 4-methoxyphenyl 4-(3,4,5-trimethoxybenzyl)-1-piperazine acetate monofumarate monohydrate (KB-5492), a novel anti-ulcer agent, for the sigma receptor in guinea-pig brain membranes. KB-5492 selectively inhibited specific [3H]1,3-di(2-tolyl)guanidine (DTG) binding to the sigma receptor (IC50 = 3.15 microM) with a pseudo-Hill coefficient of 0.33. Computer-assisted analysis revealed that KB-5492 bound to high- and low-affinity sites. Although KB-5492 had weak affinity for alpha 2-adrenoceptors at 10 microM, it was almost inactive at a concentration of 10 microM in 33 other binding assays for receptors, second messenger systems and ion channels. sigma Receptor ligands such as haloperidol, DTG, (+)-3-(3-hydroxyphenol)-N-(1-propyl)piperidine (3-PPP), rimcazole and (-)-3-PPP inhibited specific [3H]DTG binding and their IC50 values were 0.003, 0.044, 0.33, 0.67 and 1.03 microM, respectively. On the other hand, various anti-ulcer agents such as cetraxate, cimetidine, omeprazole, sofalcone, sucralfate, teprenone and troxipide could hardly displace specific [3H]DTG binding at 100 microM. Scatchard-Rosenthal analysis indicated that [3H]DTG bound to a single site, and KD and Bmax values for [3H]DTG were 87.3 nM and 679.3 fmol/mg protein, respectively. KB-5492 significantly decreased the Bmax value, but did not affect the KD value. In contrast, haloperidol and DTG significantly increased the KD values, but did not affect the Kmax values. These findings indicate that KB-5492 selectively bound to the [3H]DTG-labeled sigma receptor and that other anti-ulcer agents had little affinity for the sigma receptor.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Single-molecule analysis of the actomyosin motor using nano-manipulation.

The elementary events in energy transduction by the actomyosin motor, driven by ATP hydrolysis, were directly recorded from multiple and single molecules using a recently developed technique for nano-manipulation of single actin filaments by a microneedle. In order to avoid the effects of random orientation of myosin and association of myosin with an artificial substrate in the surface motility assay, we used single myosin-rod cofilaments with various ratios. Distinct actomyosin attachment, force generation (the power stroke) and detachment events were detected at a very low myosin: rod ratio. At high load, one power stroke generated 5-6 pN peak force and 2.3 pN force averaged over the cycle, which were compatible with those deduced from noise analysis of force fluctuations caused by multiple molecules. As the load was reduced, the length of the power stroke increased. At near zero load, the length of a power stroke was approximately 17 nm. The results suggested that an ATPase cycle produces one power stroke at high load and many ones at low load.

Actins↗
PubMed1994

Detailed analysis of loss of heterozygosity on chromosome band 17p13 in breast carcinoma on the basis of a high-resolution physical map with 29 markers.

We have constructed a physical map of chromosome band 17p13, using 29 markers that had been localized to 17p13 by means of fluorescence in situ hybridization (FISH) and analysis by pulsed-field gel electrophoresis (PFGE). The map spans nearly 8 Mb of genomic DNA, and the estimated average distance between each marker is roughly 290 kb. The p13 band of chromosome 17 is thought to contain a putative tumor suppressor gene in addition and distal to TP53. Deletion mapping in a large number of breast carcinomas indicated that the tumor suppressor gene lies between the loci defined by cC117-708 (D17S878) and p144D6 (D17S34), which are an estimated 7 Mb apart. Our results should contribute to construction of a contig map of chromosome band 17p13 with cosmid and/or YAC (yeast artificial chromosome) clones, and to isolation of the putative tumor suppressor gene.

Breast Neoplasms↗
PubMed1994

A Drosophila homolog of cadherin associated with armadillo and essential for embryonic cell-cell adhesion.

We have identified a Drosophila homolog of vertebrate classic cadherins. A monoclonal antibody to Drosophila alpha-catenin (D alpha-catenin) copurifies a 150-kDa glycoprotein (gp150) along with the alpha-catenin. To further characterize this protein, we generated monoclonal antibodies to gp150 and isolated its cDNAs using the antibodies. Predicted sequences of the encoded product revealed that it is a transmembrane protein with similarity to vertebrate classic cadherins, and so we designated this molecule DE-cadherin. The extracellular domain has six cadherin-specific repeats, although the first repeat seems to be cleaved off upon maturation, and the cytoplasmic domain shows significant identity to that of vertebrate classic cadherins. DE-cadherin is distinguishable from its vertebrate counterparts by a large insertion with local sequence similarity to Fat, laminin A chain, Slit, and neurexin I at the proximal region of the extracellular domain. Despite such differences, DE-cadherin is functionally similar to vertebrate classic cadherins. For example, it is associated with alpha-catenin and beta-catenin (Armadillo), and protected from trypsin digestion only in the presence of Ca2+, as is the case for many of classic cadherins. Transfection of S2 cells with the DE-cadherin cDNA enhances their Ca(2+)-dependent cell aggregation. Antibodies to this molecule inhibited aggregation of not only the transfectants but also early embryonic cells. DE-cadherin is concentrated at the apical poles of epithelial cell-cell junctions. All these results suggest that DE-cadherin is a homolog of vertebrate classic cadherins and that the vertebrate and invertebrate share common mechanisms for regulation of cell-cell adhesion.

Amino Acid Sequence↗
PubMed1994

Effect of betaine on S-adenosylmethionine levels in the cerebrospinal fluid in a patient with methylenetetrahydrofolate reductase deficiency and peripheral neuropathy.

A 16-year-old Japanese girl with 5,10-methylenetetrahydrofolate reductase deficiency showed peripheral neuropathy. There were no significant responses to vitamin B6, vitamin B12 or folate, given alone or in combination. With the addition of betaine monohydrate, she has been free from gait disturbance and muscle weakness. The concentration of S-adenosylmethionine in cerebrospinal fluid, which was undetectable before receiving betaine monohydrate, increased to about the normal level 24 months after treatment with betaine monohydrate.

Adolescent↗
PubMed1994

Experimental study of laparoscopic selective proximal vagotomy using a carbon dioxide laser.

This study investigated the effectiveness of laparoscopic selective proximal vagotomy using a CO2 laser. Irradiation of the stomach was performed from the serosal aspect using a defocused CO2 laser beam. In the first experiment, the inhibitory effect on cysteamine ulcers in rats was compared between surgical vagotomy and CO2 laser vagotomy using three different irradiation fields. The results suggested that irradiation near the lesser curvature provided sufficient denervation. In the second experiment, CO2 laser vagotomy was performed laparoscopically in dogs. The procedure lasted less than 1 h and a postoperative endoscopic Congo red test confirmed its effectiveness. Subserosal tissues including the vagus nerve branches showed degeneration and were replaced by fibrosis 3 months postoperatively, but the deeper tissues were spared. In conclusion, laparoscopic CO2 laser vagotomy may be as effective for reducing acid secretion as standard surgical vagotomy. Its simplicity and safety suggest that a clinical trial in humans may be warranted.

Animals↗
PubMed1994

Sequence tagged sites of microclones obtained by microdissection of a human chromosomal region 11q23 and isolation of yeast artificial chromosomes.

A human chromosomal region 11q23-specific DNA library has been constructed by means of microdissection-microcloning method with polymerase chain reaction (PCR) technique (Seki et al., Genomics 16: 1993). DNA sequences were determined for 25 microclones that contained approximately 300-500 bp insert and gave a unique (single copy) signal in Southern blot analysis. The sequence tagged site (STS) was designed and appropriate condition for PCR was determined for each unique microclone. Twelve STSs were established and used for PCR-screening of human genomic libraries constructed with yeast artificial chromosome (YAC). Thirteen YAC clones have been isolated from eight STSs. These chromosomal region-specific STSs and YAC clones will be useful in the positional cloning of disease-related genes localized to the q23 region of chromosome 11.

Base Sequence↗
PubMed1994

Detection of minute intestinal metaplastic lesions by video microscopy.

Using video microscopy in 225 resected stomachs we detected 32 minute solitary lesions of intestinal metaplasia histologically. The magnified features of the minute lesions showed a characteristic appearance and were classified into three types: mesh-like (type A), villoid (type B), and tubular (type C). All the lesions classified as type A exhibited the incomplete type of intestinal metaplasia according to the results of histopathological and/or histochemical examination. In contrast, most lesions classified as type B exhibited the complete type of intestinal metaplasia. We concluded that intentional detection of minute lesions in resected stomachs by video microscopy is simple and useful, especially in cases of minute lesions < 5 mm in diameter. Moreover, our findings demonstrate that the minute intestinal metaplastic lesions have morphological characteristics based on which they can be classified into three types of lesions. These morphological characteristics correlate with their histopathological findings.

Adult↗