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T Katsube

Publications and source records attributed to T Katsube.

At least 55 records · Page 3Linked to original sources
PubMed1998

N-glycosylation does not affect assembly and targeting of proglycinin in yeast.

Glycinin, a simple protein, and beta-conglycinin, a glycoprotein, are the dominant storage proteins of soybean and are suggested to be derived from a common ancestor. To investigate why glycinin does not require glycosylation for its maturation, we attempted N-glycosylation of proglycinin A1aB1b using site-directed mutagenesis and yeast expression system. An N-glycosylation consensus sequence Asn-X-Ser/Thr was created at positions 103, 183, 196, 284 and 457 in the variable regions being strongly hydrophilic revealed from the alignment of amino acid sequences of various glycinin-type proteins. Among five mutant proglycinins (Q103N, H183N, G198T, S284N, N459T), Q103N was fully glycosylated, and H183N and N459T were partly (around 20% of the expressed proteins), whereas others were barely or not glycosylated. The glycosylated proglycinin was susceptible to endo-beta-N-acetylglucosamidase and N-glycanase cleavages. N-glycosylation did not cause inconveniences to processing of signal peptide, assembly into trimers and targeting into the vacuoles. Thermal and trypsin sensitivity analyses of the glycosylated proglycinin suggested that N-linked glycan prevents protein-protein interaction but does not stabilize the protein conformation. The reason why glycinin does not require N-glycosylation for its maturation is discussed.

Antigens, Plant↗
PubMed1998

Direct binding between two PDZ domain proteins Canoe and ZO-1 and their roles in regulation of the jun N-terminal kinase pathway in Drosophila morphogenesis.

During Drosophila embryogenesis, the ventral epidermis dorsally expands and the left and right epithelial sheets meet and fuse along the dorsal midline. For this dorsal closure to occur, two PDZ domain proteins, Cno and ZO-1, are required. The dorsal epidermis remains open when the expression of ZO-1 and Cno are reduced simultaneously by hypomorphic mutations in the relevant loci. ZO-1 and Cno colocalize at adherens junctions in embryonic epithelia, and form a protein complex upon binding to each other. Genetic analysis showed that Cno is involved in the Jun N-terminal kinase (JNK) pathway for dorsal closure, as a modulator acting upstream of, or in parallel with, the small GTPase Drac1. The ZO-1-Cno complex may be involved in dynamic changes in cytoskeletal organization and cell adhesion during morphogenetic events associated with dorsal closure in the Drosophila embryo.

Animals↗
PubMed1998

[Relationship between telomerase activity and clinicopathological findings in gastric cancer].

In recent, telomerase has been drawing the attention, because it plays important role in cell immortalization. Since Kim et al exploited TRAP (telomeric repeat amplification protocol) assay which detected telomerase activity efficiently, telomerase activity of various tissues have been detected. In this study, telomerase activity of gastric cancer of resected or biopsy specimen were detected. And we have examined relationship between telomerase activity and clinicopathological factors. In advanced cancer, telomerase activity is negative in 2 cases and positive in 17 cases. In case with lymph node metastasis, negative in 3 cases and positive in 14 cases. In differentiated type, negative 1 cases and positive 20 cases. In noncancerous gastric mucosa, telomerase activity is positive in only 2 cases of 9 cases with intestinal metaplasia. Previous results were same in biopsy specimen. In summary, telomerase activity was detected in 76.7% of gastric cancer and most of advanced cancer or differentiated type. Some intestinal metaplasia cases with telomerase activity suggested precancerous stage.

Humans↗
PubMed1997

cDNA sequence and expression of a gene encoding a pyruvate dehydrogenase kinase homolog of Drosophila melanogaster.

Pyruvate dehydrogenase is a catalyst for an irreversible step in the degradation of glucose and its activity is regulated by a highly specific protein kinase, pyruvate dehydrogenase kinase (PDK). PDK belongs to a family of mitochondrial protein kinases unique from other eukaryotic protein kinases. We cloned a cDNA encoding a putative PDK from Drosophila melanogaster (DmPDK). The deduced DmPDK consists of 413 amino acids and shares up to 57.8% homology with human and rat PDK isoenzymes. Developmental Northern blot analysis revealed two major transcripts of 2.1 kb and 2.7 kb. The 2.7-kb transcript was expressed throughout ontogeny, whereas the 2.1-kb transcript was specific to embryos and adult females. Whole-mount in situ hybridization revealed that PDK mRNA is ubiquitously distributed in the embryo. The DmPdk gene was cytologically mapped to the 45CD region on the right arm of the second chromosome.

Amino Acid Sequence↗
PubMed1995

A role for the distal CCAAT box of the gamma-globin gene in Hb switching.

Hereditary persistence of fetal hemoglobin (HPFH) is a condition manifested by continued expression of the gamma-globin gene in adult life. The four types of HPFH mutations (-117 G-A, -114 C-T, -114 C-G, and 13 bp del) clustered in the vicinity of the distal CCAAT box of the gamma-globin gene suggest the relevance of this region to the fetal-to-adult hemoglobin switching. Functional analysis in erythroid cell lines showed that these HPFH mutations reduced the activity of the gamma-globin promoter in K562 expressing embryonic and fetal globin chains, but not in KU812 expressing fetal and adult globin chains. These results suggest that the distal CCAAT box region has different functions in the fetus and the adult. In vitro, binding of NFE3 to the distal CCAAT box was commonly reduced by these HPFH mutations, suggesting that the binding of NFE3 to the distal CCAAT box may repress the gamma-globin gene in adults. Overlap of the binding sites of NFE3 and CP1, a potential activator, indicates the regulation of the gamma-globin gene by the competition between these factors. In addition, an unknown factor interacting with the -114 C-T HPFH mutant CCAAT box may be involved in elevation of the gamma-globin expression in an individual with the -114 C-T mutation.

Base Sequence↗
PubMed1995

Modification tolerability of soybean proglycinin.

Proglycinins containing multiple modifications, that is, with two kinds of single modifications, designed previously to improve food functions, were assessed for ability to form proper conformations. This was done to discover the modification tolerability of proglycinin. Based on our results, three new criteria are proposed for judging formation of proper conformations. Our results suggest that proglycinin molecules tolerate different combinations of single modifications without misfolding.

Amino Acid Sequence↗
PubMed1995

[A case of advanced esophageal cancer made resectable by preoperative combination therapy with 5-FU and CDDP].

The authors experienced a case of advanced esophageal cancer made resectable by combination therapy with 5-FU and CDDP as a neoadjuvant chemotherapy. The patient was a 69-year-old-man suffering from esophageal cancer of A3.N4 (+).Pl0.M0 at stage IV. At this case was diagnosed to be radically unresectable, this form of combination therapy was used. The patient showed PR after 2 courses and the operation could then be conducted. The intraoperative findings revealed fibrous fusion of tumor with the aorta, but no direct invasion. The metastatic lymph nodes were necrotized and reduced. It was evaluated as Grade 3 in accordance with the "Histologic criteria for the effects of anticancer chemotherapy." The postoperative course was favorable without recurrence. This therapy caused no adverse reactions and seems effective as a neoadjuvant chemotherapy for advanced esophageal cancer.

Aged↗
PubMed1995

[Study on pyrimidine nucleoside phosphorylase (PyNPase) activity in resected tissues of patients with gastric cancer].

Pyrimidine nucleoside phosphorylase (PyNPase) activity was measured in gastric cancer tissue from 25 patients who underwent resections of gastric cancer. The relation between the activity and host and tumor factors in gastric cancer was studied, and the following results were obtained. 1. PyNPase activity was 128.3 +/- 99.5 in cancer tissue and 37.2 +/- 23.1 in non-cancer tissue. The level was significantly higher in cancer tissue (p < 0.0001). 2. With respect to host factors, the PyNPase activity tended to be high in patients in whom cell-mediated immune response was maintained. 3. With respect to tumor factors, the values tended to be high in patients who were positive for lymph vessel and venous invasion, and positive for lymph node metastasis. 5'-deoxy-5-fluorouridine(5'-DFUR) is an anticancer agent which manifests antitumor effects when it is transformed into 5-FU by PyNPase. When this agent is administered to gastric cancer patients, it can be expected to be more effective in the above types of patients because of its characteristics.

Adult↗
PubMed1995

[Portal hemodynamic changes from TIPS--evaluation with pulse Doppler method].

Transjugular intrahepatic portosystemic shunt (TIPS) was applied in three patients with Child C liver cirrhosis. Portal venous pressure was reduced by an average of 10.7 mmHg, and results such as the disappearance of esophageal varices and reduction in ascites were obtained. The portal hemodynamics of these three patients was observed before and after TIPS using the pulse Doppler method. When portal hemodynamics in the main portal vein was examined before TIPS, it was found that the mean blood flow velocity had decreased, the blood flow volume was reduced and the cross-sectional area of the vein had increased. The congestion index was high and there was definite congestion of the portal venous system. After TIPS, the blood flow velocity and volume increased, the cross-sectional area of the vein was reduced and the congestion index was lower. Congestion of the portal venous system was improved in these three patients and the clinical efficacy of TIPS was proven by these results. If the stent can be detected sonographically, stent patency is easily confirmed with the pulse Doppler method which is usefull examination technique for follow-up of patients undergoing TIPS.

Aged↗
PubMed1995

[Influence of intratumor administration of OK-432 on the tumor selectivity of 5'-DFUR].

The influence of intratumor administration of OK-432 on the tumor-selective antitumor effect of 5'-DFUR was studied in 49 patients with advanced gastric cancer. The patients were divided into 4 groups that received oral 5'-DFUR, intratumor OK-432, oral 5'-DFUR plus intratumor and intracutaneous OK-432, or no therapy before operation. Using surgical specimens, the PyNPase activity and 5-FU content were measured, and the localization of PyNPase was determined immunohistologically. The results were as follows: 1) 5'-DFUR therapy decreased intratumor PyNPase activity whereas administration of OK-432 increased it. 2) PyNPase activity was higher in cancer tissue than in normal tissue for all groups. 3) The 5-FU content of cancer tissue was higher in patients receiving OK-432 plus 5'-DFUR than in patients receiving 5'-DFUR alone. 4) In the resected tumors, PyNPase was mainly localized in the cancer cells of some patients and in the stromal cells of others. Thus, the localization of PyNPase showed two major patterns.

Antineoplastic Agents↗
PubMed1995

Molecular analysis of the human fetal-to-adult globin switching.

Hereditary persistence of fetal hemoglobin (HPFH) is a condition characterized by continued expression of the gamma-globin gene in adult life. Analysis of a Japanese HPFH family had revealed that the C-T transition at position -114 within the distal CCAAT box of the gamma-globin gene associated with the HPFH allele. In the vicinity of the distal CCAAT box, other two mutations (-117 C-T, 13 bp del) had been identified in individuals with a HPFH phenotype. Functional analysis of these mutant promoters in erythroid cell lines suggested that the distal CCAAT box works positively in the fetus but negatively in the adult on the expression of the gamma-globin gene. Further study on transgenic mice showed that the -114 mutation was responsible for the elevated expression of the gamma-globin gene in the adult. To elucidate the molecular mechanism underlying the persistent expression of the gamma-globin genes associated with the HPFH mutations, interaction of the mutant promoters with nuclear factors was analyzed. Relevance of the nuclear factor, NFE3, to the gamma-globin regulation was suggested by the affected binding of NFE3 to the altered distal CCAAT boxes with HPFH mutations (-117, -114, 13 bp del).

Adult↗
PubMed1994

Clinical studies of type-I procollagen carboxyterminal peptide in serum of patients with gastric cancer: comparison with CEA and CA19-9.

The serum level of a newly developed monoclonal antibody against type-I procollagen carboxyterminal peptide (P-1-P) was determined in patients with gastric cancer. The location of P-1-P in gastric cancer tissue was also investigated. We found that: (1) The serum P-1-P level and the positivity rate in patients with gastric cancer were similar to those in patients with other malignant or benign GI diseases and healthy individuals. (2) In patients with gastric cancer, the P-1-P positivity rate was significantly lower than that of CEA or CA19-9. (3) In patients with gastric cancer, the P-1-P positivity rate increased as the disease stage advanced. (4) Among patients with gastric cancer, the P-1-P positivity rate was significantly higher in those with scirrhous type than in those with medullary or intermediate type. (5) P-1-P was detected in the cytoplasm of cancer cells. P-1-P staining was stronger in scirrhous type and histologically undifferentiated gastric cancer. These results show that P-1-P can serve as a good marker for scirrhous type gastric cancer. The production of collagen by cancer cells themselves seems to be involved in collagen production in scirrhous type gastric cancer.

Adenocarcinoma, Scirrhous↗
PubMed1994

Crystallization and preliminary X-ray analysis of soybean proglycinins modified by protein engineering.

Glycinin is one of the most abundant storage proteins in soybean seeds. We earlier reported the preparation of proglycinins modified by protein engineering to improve food functions. Crystals of the modified proglycinins (delta I, delta V8, IV + 4Met, V + 4Met, Gly12, and Ser88) expressed in Escherichia coli were grown, each under different suitable crystallization conditions. The crystals of delta I, V + 4Met, Gly12, and Ser88 diffracted X-rays sufficiently for crystallographic analysis. delta I, Gly12, and Ser88 crystals were tetragonal, space group P4(1) or P4(3), and with unit cell dimensions a = b = 114.3-115.9 A and c = 145.1-146.1 A. V + 4Met crystals were monoclinic, space group P2, and with unit cell dimensions a = 118.7 A, b = 78.1 A, c = 109.9 A, and beta = 119 degrees. The number of promoters per asymmetric unit of all of the crystals of these four modified proglycinins was about 3. This value is consistent with proglycinins being trimers. These data indicated that most of the modified proglycinin crystals examined here could be studied by X-ray crystallography to elucidate the relationships between the structure and the functional properties of glycinin at molecular level.

Amino Acid Sequence↗
PubMed1994

[Study on intratumor administration of lentinan--primary changes in cancerous tissues].

Lentinan was administered for gastric cancer in order to determine what type of changes would occur as a consequence. In an experimental study, the intraperitoneal administration of lentinan on cancerous tissues caused a marked development of reticular fibers, along with an enhanced interstitial response. Findings which support the relationship between a marked development of reticular fibers and an anti-tumor effect, were also obtained. Furthermore, lentinan was administered for human gastric cancer to evaluate whether or not an increase in interstitial response would be observed. As a result, reticular fibers developed in tumor sites with a resultant fragmentation of cancer cell nests. Many T lymphocytes infiltrated cancer sites where the lentinan was administered. These findings suggest that the intratumor administration of lentinan enhanced an interstitial response and also activated an anti-tumor immune response in the human gastric cancer tissues.

Animals↗