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41.
Kunii Y Kamada M Ohtsuki S Araki T Kataoka K Kageyama M Nakagawa N Seino Y 《Acta medica Okayama》2003,57(4):191-197
This study was designed to explore whether it was possible to evaluate the severity of VSD, PDA, and ASD by measuring brain natriuretic peptide (BNP) levels. We also investigated normal BNP levels in children to provide a baseline for our study. We measured BNP levels in 253 normal children, including 11 normal neonates, and in 91 VSD patients, 29 PDA patients, and 34 ASD patients. BNP levels showed no age-related differences in normal children (the mean value: 5.3 +/- 3.8 pg/ml). In the healthy neonates, BNP levels rose from 10.4 +/- 11.9 pg/ml in cord blood to 118.8 +/- 83.2 pg/ml on day 0, then fell to 15.3 +/- 7.8 pg/ml by day 7. In VSD and PDA patients, BNP levels correlated significantly with Qp/Qs, LVEDV, and peak RVP/LVP. In ASD patients, BNP levels correlated with Qp/Qs and RVEDV. Especially, in VSD patients, as an index corresponding to 1.5-2.0 of the Qp/Qs ratio, BNP levels of 20-35 pg/ml were found to be best with regard to both sensitivity and specificity. In the healthy neonates, BNP levels changed rapidly after birth. In VSD, PDA, and ASD patients, BNP levels were well-correlated with the severity of the disease. Especially, in VSD patients, it that appears BNP levels may be useful in evaluating surgical indications, with 20-35 pg/ml levels being the appropriate cut-off value. 相似文献
42.
43.
Cortical spreading depression (SD) is characterized by propagation of neuronal/glial membrane depolarization throughout the unilateral cerebral cortex and has been linked to several neurological disorders, including migraine aura and epilepsy. SD induction resulted in a dramatic increase in BrdU-incorporated cells in the ipsilateral cortical hemisphere that was dependent on the number of elicited SD. Immunohistochemical studies revealed that 53% of the BrdU-labeled cells in the SD-generated cortex were NG2 immunopositive and 25% were OX-42 immunopositive. The remaining 22% of BrdU-incorporated cells showed no immunoreactivity to GST-rr, GFAP, NeuN, NG2 or OX-42.These data indicate that functional excitation of the cerebral cortex induces proliferative response in cortical cells, which may subsequently differentiate into glial progenitor or microglia within 3 days after stimulation. 相似文献
44.
Masuyama K Taniguchi I Kataoka N Ohno M 《Genes to cells : devoted to molecular & cellular mechanisms》2004,9(10):959-965
Different classes of RNA are exported to the cytoplasm by distinct mechanisms. Each class of RNA forms distinct complexes with nuclear proteins prior to its export to the cytoplasm. In our attempt to obtain comprehensive information of protein factors that specifically associate with mRNAs in the nucleus, we performed in vivo UV-crosslinking analysis after microinjection of various RNAs into Xenopus oocyte nucleus. We found a group of proteins preferentially crosslinked to mRNAs. Immunoprecipitation experiments revealed that some of the crosslinked signals corresponded to SR (serine/arginine-rich) proteins, a family of essential RNA-binding proteins involved in pre-mRNA splicing. It was previously suggested that some members of SR protein family are involved in export of a specific intronless mRNA, histone H2A mRNA and some spliced mRNAs. However, it is still to be clarified if SR proteins are involved in export of general mRNAs, especially general intronless mRNAs that do not contain specific RNA export elements. When we microinjected an antibody against SR proteins into the nucleus, export of mRNAs was severely inhibited, regardless of whether the mRNAs were produced via pre-mRNA splicing or not, whereas export of other RNAs was not affected. These results unequivocally showed that SR proteins are involved in export of both general intronless and spliced mRNAs. 相似文献
45.
Akihisa Kataoka Naoki Nishimura Noboru Uchiyama Hiroshi Ono Jun Kishi Naohiko Chonabayashi 《Arerugī》2007,56(7):685-690
BACKGROUND: Many drugs and the combinations of drugs are recommended for each treatment step in bronchial asthma. However, there are few issues examined about the optimal drug and combination of drugs in a long term prognosis. In this study, we investigated the optimal drugs and combinations of drugs from a point of view of prognosis. METHODS: One hundred and ninety four patients who visited our hospital for treatment from November, 2003 to October, 2004 and were managed according to GINA guideline were surveyed retrospectively. We compared the rate of step up and the frequency of urgent visit and urgent hospitalization in one year between drug groups in each treatment step. RESULTS: The rate of step up was significantly higher in leukotriene receptor antagonist (LTRA) group than in inhalation corticosteroid (ICS) group and theophylline group in Step 2. The frequency of urgent visit and urgent hospitalization was significantly higher in ICS+LTRA group than in ICS+theophylline group and ICS+long-acting beta 2-agonist (LABA) group in Step 3. CONCLUSION: There is a possibility that the prognosis becomes bad when we use LTRA in the practical treatment according to GINA guideline. 相似文献
46.
Shigeru Amano Hideo Kataoka Fumitada Hazama Minora Nakatake Atsuhiko Maki 《Pathology international》1985,35(4):969-974
Hepatocellular carcinoma (HCC) showing marked elevation of serum alpha fetoprotein (AFP) (maximum; 70942.0 ng/ml at the end stage) and serum carcinoembryonic antigen (CEA)(maximum; 7368.4 ng/ml at the end stage) was surgically resected. In the resected liver, there were two different tumor nodules which were adjacent to each other but clearly separated by a thin connective tissue. One of the nodules was a well differentiated and the other was poorly differentiated HCC. Immunoperoxidase study revealed that both CEA and AFP were localized in the tumor cells of the poorly differentiated HCC. This is the first report which clearly proved CEA synthesis in the cells of HCC. Serial staining showed that there was simultaneous synthesis of CEA and AFP in some of the tumor cells. ACTA PATHOL. JPN. 35: 969–974, 1985. 相似文献
47.
An electron microscope study of the development of the exocrine and endocrine pancreas with special reference to intercellular junctions 总被引:1,自引:0,他引:1
Intercellular junctions in pancreatic acinar, duct and endocrine cells were studied by thin section and freeze-fracture methods in developing rats and mice. Undifferentiated cells were joined by the zonula occludens and isolated fragments of tight junctional strands. Small gap junctions were either occasionally associated with tight junctional strands or appeared independent of them. During the morphological differentiation of acinar cells, strands of the zonula occludens developed to form a complicated meshwork while gap junctions rapidly increased in size. Duct cells were joined by the less-developed zonula occludens but gap junctions were rarely seen. In the neonate, intercellular junctions were similar to those in adult acini and intercalated ducts. Endocrine cells were joined by maculae occludentes and small gap junctions. During late prenatal days, the macula occludens increased in size and gap junctions in number. Sometimes tight junctional strands disappeared to leave membrane elevations, some of which were associated with small gap junctions. Maculae occludentes on endocrine cells were gradually fragmentized and diminished during postnatal development. They were completely lost in the rat. These results suggest that intercellular junctions play important roles in pancreatic development. In particular, the transient development of maculae occludentes is associated with endocrine cell development, and intercellular communication mediated by gap junctions may be important for the differentiation of acinar and endocrine cells. 相似文献
48.
Kazuki Nabeshima Teruhiko Inoue Yoshiya Shimao Hiroaki Kataoka M. Koono 《Virchows Archiv : an international journal of pathology》1998,433(3):243-253
We have already presented a two-dimensional cell motility assay using a highly metastatic variant (L-10) of human rectal
adenocarcinoma cell line RCM-1 as a motility model of tumour cells of epithelial origin. In this model, L-10 cells showed
locomotion as a coherent sheet when stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA), and we called this type of movement ”cohort migration”. Electron and immunoelectron
microscopic study of the migrating cell sheets demonstrated localized release from cell–cell adhesion only at the lower portion
of the cells with loss of E-cadherin immunoreactivity, and this change was associated with increased tyrosine phosphorylation
of the E-cadherin–catenin complex, including β-catenin. Cell–extracellular matrix (ECM) interactions involved in this TPA-induced
cohort migration and their effect on tyrosine phosphorylation of the E-cadherin-catenin complex have now been investigated.
L-10 cell cohort migration was almost completely inhibited by addition of Arg-Gly-Asp (RGD) peptide into the medium, and thus
RGD dependent. Cohort migration was stimulated on type I and IV collagens, fibronectin (FN)- and laminin-coated substratum,
but was inhibited by RGD only on FN-coated surface. By using immunofluorescent techniques, FN was demonstrated preferentially
around migrating cells, and a protein synthesis inhibitor, cycloheximide, inhibited the migration by about 75%. FN produced
by L-10 cells were found to be mostly EDA+ FN when analysed by RT-PCR. Moreover, anti-FN antibody, but not anti-vitronectin
antibody, inhibited the TPA-induced cohort migration almost completely. Thus, it was likely that L-10 cells produced FN themselves
and moved on the FN substrate in an RGD-dependent manner. However, stimulation of migration by type I collagen coating and
inhibition by RGD treatment did not affect the tyrosine phosphorylation of the E-cadherin–catenin complex induced by TPA,
indicating that cell–cell interactions were adjusted to suit cell migration, irrespective of the condition of cell–ECM adhesion,
during TPA-induced cohort migration.
Received: 31 December 1997 / Accepted: 2 April 1998 相似文献
49.
A mesenchymal chondrosarcoma found in a 7-year-old Holstein cow was studied by light and electron microscopy. There was a primary site in the subcutaneous tissue at the base of the neck and metastases in the lungs, pleura, broncho-mediastinal lymph nodes, kidneys and heart. The neoplasm was composed of undifferentiated mesenchymal tissue, myxoid tissue and chondroid tissue. The neoplastic cells of the former two tissues were characterized by desmosome-like junctions and moderate to small amounts of rough endoplasmic reticulum (RER). 相似文献