Biomedical subjects

N Tanaka

Publications and source records attributed to N Tanaka.

At least 73 records · Page 4Linked to original sources

PubMed2003

Proteome analysis of rice tissues by two-dimensional electrophoresis: an approach to the investigation of gibberellin regulated proteins.

Protein databases constructed using high-resolution two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) were used to explore the proteome expressed in various rice tissues. Proteins from leaf sheath, root, and cultured suspension cells were systematically analyzed using 2D-PAGE, mass spectrometry and Edman sequencing, followed by database searching. In all, 79 of the 431 spots detected by 2D-PAGE in the leaf sheath, 73 of the 508 spots in the root and 140 of the 962 spots in the cultured suspension cells could be identified. Protein lists were constructed for each tissue and used to investigate the effects of gibberellin (GA) treatment. In the leaf sheath, root and cultured suspension cells, 8, 21, and 14 of the identified proteins, respectively, were regulated by GA. These proteins included polypeptides involved in general metabolism, energy production, transcriptional regulation and signal transduction in the leaf sheath; in metabolism and defense in the root; and in metabolism, energy production, cell growth, defense and signal transduction in the cultured suspension cells. These results indicate that the proteome databases assembled in these studies will be useful for the rapid assessment of changes in protein content in specific tissues, and that proteins regulated by GA may play a significant role in tissue growth.

Cells, Cultured↗

PubMed2003

Expression of E-cadherin, alpha-catenin, and beta-catenin in the process of lymph node metastasis in oral squamous cell carcinoma.

Regional lymph node metastasis is a very important prognostic indicator. In the metastatic process, reduction in cell to cell adhesion including E-cadherin-catenin cell adhesion complex is an essential step. We investigated immunohistochemical expression of E-cadherin, alpha-catenin and beta-catenin in 159 tissue samples from patients with oral squamous cell carcinoma and examined the correlation between their expressions and the presence of regional lymph node metastasis. Significantly greater reduction in expression levels of E-cadherin, alpha-catenin and beta-catenin was found in the metastatic group (n=64) compared to the nonmetastatic group (n=95) (P=0.007, 0.001, 0.001, respectively). However, there was no significant correlation between their expressions and the features of the regional metastasis, the number of metastatic lymph nodes or the presence of extracapsular metastasis. These data suggest that evaluation of the immunohistochemical expression of E-cadherin, alpha-catenin and beta-catenin is extremely valuable for the diagnosis of metastatic occurrence.

Adult↗

PubMed2003

The effectiveness of insect-pollination test to evaluate the level of self-incompatibility and their genetic analysis in radish (Raphanus sativus L.).

We have tried an insect-pollination self-incompatibility (SI) test to strictly evaluate the level of SI as a model for the actual F(1) seed production field using radish as experimental material. Twelve inbred lines, homozygous for the S-alleles, were used in the artificial self-pollination and the insect-pollination SI test. There was a positive correlation ( r = 0.606) between the results by these two methods. Some lines showed a low level of SI in the insect-pollination test despite showing a high level of SI in the artificial self-pollination test. On the other hand, no lines showing a low level of SI in artificial self-pollination had a high level of SI in insect-pollination. These results show that the insect-pollination SI test can be considered to be a more reliable and stricter method than the artificial self-pollination test with respect to an evaluation of SI levels. We have raised and analyzed an F(2) population and F(3) lines derived from an F(1) cross between a line showing a high level of SI (R00-04) and one showing a low level. The rate of self-seed settings of the F(2) population showed a binomial distribution. There were 39 high-level SI plants to 15 low-level SI plants. This result and F(3) progeny tests suggested that the high level of SI which R00-04 showed is controlled by a dominant gene.

Animals↗

PubMed2003

A novel method for gene delivery and expression in esophageal epithelium with fibrin glues containing replication-deficient adenovirus vector.

BACKGROUND: Gene transfer to the esophageal epithelium holds the potential for the therapy of malignant as well as premalignant lesions in the upper gastrointestinal tract. Replication-deficient recombinant adenoviruses represent an efficient means of introducing genes in vivo into cells in a variety of organs. The majority of in vivo studies utilize direct submucosal injection for delivery of the viral vectors into the locoregional area of the gut; transferring genes into epithelial cells, however, is difficult because viruses are retained in the subepithelial space. To establish the efficient method for gene transfer into the epithelial cells, we have developed a multiluminal spray catheter that can be passed through the accessory channel of an endoscope, and we have evaluated the feasibility of fibrin glues as a vehicle of recombinant adenoviruses in a porcine model. METHODS: The fibrinogen solution and the thrombion solution containing an E1/E3 deleted recombinant adenovirus expressing the bacterial lacZ gene (Ad-lacZ) were endoscopically sprayed on the porcine esophagus through the catheter attached to the dual-barrel syringe. Twenty-four hours after gene delivery, beta-galactosidase activity of the esophagus was determined under the microscope following X-gal staining. RESULTS: The fibrin glue could be locally sprayed on the porcine esophagus by using the multichannel catheter through the endoscope. Attachment of the fibrin glue comtining Ad-lacZ caused strong beta-galactosidase staining on epithelial cells in the mucosal surface, but not in the basal cell layer. CONCLUSION: Endoscopic local delivery of recombinant adenoviruses in aerosolized fibrin glues through a multiluminal catheter could provide an optimal technique for gene transfer into epithelial cells in the mucosal surfece, which may have important implications for the treatment of human esophageal premalignant diseases.

Adenoviruses, Human↗

PubMed2003

Mechanical stimuli enhances the expression of RGD-CAP/betaig-h3 in the periodontal ligament.

RGD-CAP, a member of the fasciclin family, is expressed in the periodontal ligament (PDL). Since the PDL is continually subjected to mechanical forces from such orofacial functions as mastication, biting, speech and swallowing, the mechanical stimuli is thought to be associated with the expression of RGD-CAP. Furthermore, the adhesive functions of RGD-CAP may contribute to the maintenance or regeneration of PDL architecture. The objective of this study was to examine whether mechanical stimuli modulate the expression of RGD-CAP in the human PDL, and to examine the effects of recombinant RGD-CAP on the adhesion of PDL cells. During experimental tooth movement, the expression of RGD-CAP was significantly enhanced in the PDL. In vitro experiments with cultured PDL cells showed that the expression of RGD-CAP mRNA was significantly enhanced by mechanical tensile force of 15.4kPa for 48h. The induction of RGD-CAP mRNA, meanwhile, was completely inhibited by cycloheximide which is an inhibitor of protein synthesis. Furthermore, neutralising antibody against TGF-beta also suppressed the mechanical induction of RGD-CAP. The adhesion of cultured PDL cells onto plates coated with recombinant RGD-CAP increased significantly compared with the controls. These findings suggest that RGD-CAP, induced by TGF-beta expressed in response to mechanical stimuli, plays an important role in modulating the homeostasis of PDL.

Blotting, Western↗

PubMed2003