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11.
Shuichi Seki Hiroki Sakaguchi Nobuyoshi Kawakita Atsushi Yanai Tetsuo Kuroki Kenzo Kobayashi 《Virchows Archiv : an international journal of pathology》1993,422(2):133-143
The proliferative activity and ultrastructural characteristics of proliferating biliary epithelial cells were analysed immunohistocytochemically in 39 biopsied liver specimens from patients with acute viral hepatitis, chronic hepatitis and liver cirrhosis using a monoclonal antibody against DNA polymerase (DNA-PA). In acute viral hepatitis with perivenular confluent necrosis, proliferation of typical bile ducts was found frequently in portal areas. In chronic aggressive hepatitis and cirrhosis, ductular proliferation of both typical and atypical forms was found in enlarged portal and periportal areas and in confluent necrotic areas. The number of proliferating biliary epithelial cells that stained positive for DNA-PA was small. There were very few positively stained cells in atypical bile ducts in confluent necrotic areas of cirrhosis. Atypical bile ducts seen in chronic aggressive hepatitis, cirrhosis and acute hepatitis with confluent necrosis were positively stained for both cytokeratins 8 and 19. In cirrhosis, the number of stained biliary epithelial cells in typical bile ducts was larger than the number of such cells in atypical bile ducts (P< 0.01). By electron microscopy, the cells positively stained for DNA-PA were mostly so-called clear cells with irregular nuclei containing coarse nucleoplasm, and a few small cells with scanty cytoplasm and few organelles. 相似文献
12.
An insulin-nonresponsive variant was isolated from mutagenized mouse BALBc/3T3 fibroblasts. Selection was based on the insulin's mitogenic action upon quiescent cells and subsequent arrest at mitosis by vinblastine sulfate to remove insulin-responsive cells. Among four surviving colonies, one, designated IN-2, exhibited no binding for [125I] insulin at 2× 10–10 M and at 4° C. The binding ability, however, recovered substantially at 15° C and increased with higher temperature and at higher ligand concentrations. The binding profiles, Scatchard plot analysis, and the dissociation kinetics indicated that the receptors expressed on IN-2 cells possess lower affinity than the parental 3T3 cells. The IN-2 cells were negative for stimulating effects of insulin on 2-deoxyglucose uptake, thymidine incorporation, and cell growth. The IN-2 cells were also negative for cross-reactivity to antibodies which react with insulin receptors on 3T3 cells and for the susceptibility to a cytotoxic chimeric insulin which was cross-linked to diphtheria toxin fragment A. This negative response of IN-2 cells can be attributed to a deficiency in high-affinity receptors for insulin. The insulin bound to the low-affinity binding sites of IN-2 cells, however, undergoes internalization and intracellular degradation. Therefore, such processing by itself does not account for insulin's mitogenic action. 相似文献
13.
Masanori Taira Jun Kudoh Shinsei Minoshima Taizo Iizasa Hideaki Shimada Yoshiko Shimizu Masamiti Tatibana Nobuyoshi Shimizu 《Somatic Cell and Molecular Genetics》1989,15(1):29-37
Complementary DNA clones for phosphoribosylpyrophosphate synthetase subunits I and II (PRS I and PRS II) were used to determine the chromosomal localization of the corresponding human genes. Southern blot analysis of genomic DNAs isolated from human placenta and a panel of humanmouse somatic cell hybrids revealed that the rat PRS I cDNA probe detected at least five human specific DNA segments (23, 20, 14.5, 6.7, and 4.3 kb) in BamHI digests. The 23-, 14.5-, and 6.7-kb DNA segments were detected only if the hybrids contained human chromosome X or translocation chromosome 7p
+ (7qter>7p22::Xq21>Xqter), indicating the location of these segments to Xq21-qter (PRPS1). The 20- and 4.3-kb DNA segments did not cosegregate with the other three segments, and spot blot hybridization analysis using flow-sorted human chromosomes indicated that these are the PRPS1-related genes (PRPS1L1 and PRPS1L2) and could be assigned to chromosomes 7 and 9, respectively. The human-specific PRS II cDNA probe revealed a BamHI DNA segment (17 kb), which segregated condordantly with the X chromosome but not with the PRPS1 gene. We surmise that the gene for PRS II (PRPS2) is located at a different region of the X chromosome, namely Xpter-q21.Preliminary report of this research was presented at Ninth International Workshop on Human Gene Mapping, Abstract supplement p. 5 (1987). 相似文献
14.
15.
Kurose T Okumura Y Sato S Yamamoto Y Akaki S Takeda Y Kanazawa S Ando A Date H Shimizu N Hiraki Y 《Acta medica Okayama》2004,58(1):7-15
We evaluated the respiratory functions of patients with pulmonary emphysema who underwent lung volume reduction surgery (LVRS) by the mean transit time (MTT) with Xe-133 lung ventilation scintigraphy, forced expiration volume in 1 sec (FEV1.0), residual volume (RV), distance walked in 6 min (6-min walk), and the Hugh-Jones classification (H-J classification) before and after LVRS. In 69 patients with pulmonary emphysema (62 men, 7 women; age range, 47-75 years; mean age, 65.4 years +/- 6.1, preoperative H-J classification, III (two were II)-V) who underwent LVRS, all preoperative and postoperative parameters (MTT 3 weeks after LVRS and the others 3 months after LVRS) were judged statistically by the Wilcoxon signed-ranks test and Odds ratio. Every postoperative parameter was improved with a significant difference (P < 0.05) compared to preoperative parameters. MTT at 3 weeks after LVRS was not associated with %FEV1.0 and the H-J classification at 3 months after LVRS, but was associated with RV and a 6-min walk at 3 months after LVRS. MTT was useful for the clinical evalution of aerobic capability after LVRS. 相似文献
16.
Yasutake N Matsuzaki T Kimura K Hashimoto S Yokokura T Yoshikai Y 《Medical microbiology and immunology》1999,188(1):9-14
The involvement of several cytokines in the antitumor effect induced by intrapleural (i.pl.) injection of heat-killed cells
of Lactobacillus casei strain Shirota (LC 9018) in mice was investigated. Injection of LC 9018 i.pl. into Meth A fibrosarcoma (Meth A)-bearing mice
not only significantly prolonged the survival of the mice, but also effectively inhibited the accumulation of malignant pleural
fluid in the thoracic cavity. In the thoracic cavity of tumor-bearing mice treated with LC 9018, we observed large amounts
of several cytokines including interleukin (IL)-1β, interferon (IFN)-γ, IL-12 and tumor necrosis factor (TNF)-α. Both anti-IFN-γ
and anti-IL-12 monoclonal antibody (mAb) treatments partially diminished the antitumor activity of LC 9018 in vivo, while
the treatment of anti-IL-1β mAb did not influence the survival of the mice. However, anti-TNF-α mAb treatment completely abolished
the antitumor effect of LC 9018 in vivo, suggesting that in this model LC 9018 has a survival-prolonging effect involving
certain cytokines. Moreover, i.pl. injection of mouse recombinant TNF-α into Meth A-bearing mice pretreated with anti-TNF-α
mAb partially restored the survival-enhancing effect of LC 9018. These results led us to conclude that TNF-α induced by i.pl.
injection of LC 9018 plays an important role in the antitumor effect of LC 9018 in vivo.
Received: 22 February 1999 相似文献
17.
John H. Hunts Nobuyoshi Shimizu Tadashi Yamamoto Kumao Toyoshima Glenn T. Merlino Young-hua Xu Ira Pastan 《Somatic Cell and Molecular Genetics》1985,11(5):477-484
The epidermal growth factor (EGF) receptor, along with several oncogene protein products, possesses tyrosine-specific protein kinase activity. Furthermore, the EGF receptor has structural similarity to the putitive v-erb-B transforming protein. Because of these closely shared characteristics, it is important to elucidate the possible involvement of the EGF receptor in malignant transformation. The epidermal carcinoma cell line A431 exhibits an abnormally high number of EGF receptors, which is associated with the presence of translocation chromosome M4. Recently, A431 cells have been shown to contain amplified sequences for the EGF receptor gene(s) and also to produce a variant mRNA which diverges from the normal EGF receptor mRNA at the 3 end. Here we report, using the human EGF receptor cDNA probe pE7, that the chromosome M4 has a six-to sevenfold amplification of the EGF receptor gene. Furthermore, the presence of M4 in somatic cell hybrids correlates with the production of the variant 2.9-kb mRNA. This aberrant mRNA is apparently generated by an intrachromosomal rearrangement which was detected using as a probe a fragment of the pE15cDNA encoding the variant mRNA. 相似文献
18.
Nobuyoshi Kittaka MD PhD Satomi Nakajima MD Takaaki Hatano MD Yukiko Seto MD Hiroki Kusama MD PhD Saki Matsui MD PhD Minako Nishio MD PhD Fumie Fujisawa MD PhD Keiichiro Honma MD PhD Takahiro Nakayama MD PhD Yasuhiro Tamaki MD PhD 《The breast journal》2021,27(11):804-810
The ACOSOG Z0011 trial has resulted in the omission of axillary lymph node dissection (ALND) in early breast cancer patients with one or two metastatic sentinel lymph nodes (SLNs). There has been increasing interest in the necessity of intraoperative assessment of SLNs in patients treated based on the Z0011 criteria. We evaluated the utility of intraoperative assessment in these eligible patients. A total of 1396 patients were treated following the Z0011 criteria from April 2012 to December 2019. We examined the proportion and clinicopathological features of patients who underwent ALND due to three or more metastatic SLNs and the sensitivity of intraoperative assessment. Only 16 (1.1%) patients had three or more metastatic SLNs diagnosed by intraoperative assessment, and they immediately underwent ALND. Of the clinicopathological factors, high clinical tumor stage (p = 0.002) and high Ki-67 labeling index value (p = 0.056) were more likely to be associated with the presence of three or more metastatic SLNs. The major independent risk factor for three or more metastatic SLNs was high clinical tumor stage (OR 3.94 [95% CI 1.42–11.0]; p = 0.009). Intraoperative assessment had low sensitivity (70.5%) and a high false-negative rate (29.5%) in detecting SLN metastases. The main finding of our study was the small proportion of patients who required ALND due to three or more metastatic SLNs according to the Z0011 criteria. The Z0011 strategy enables intraoperative assessment of SLNs to be omitted in early breast cancer patients. 相似文献
19.
20.
Nobuyoshi Suto Lauren M Tanabe Jennifer D Austin Elizabeth Creekmore Paul Vezina 《Neuropsychopharmacology》2003,28(4):629-639
Previous exposure to amphetamine (AMPH) in the ventral tegmental area (VTA) enhances cocaine self-administration in a D(1) dopamine receptor-dependent manner. The present study examined the contribution of VTA NMDA, AMPA/kainate, and metabotropic glutamate (mGlu) receptors to this effect. Rats in different groups received three intra-VTA injections, one every third day, of either saline (0.5 microl/side), AMPH (2.5 microg/0.5 microl/side), AMPH+CPP (NMDA receptor antagonist; 10 microM or 100 microM/0.5 microl/side), AMPH+CNQX (AMPA/kainate receptor antagonist; 0.3 mM or 1 mM/0.5 microl/side), AMPH+MCPG (mGlu receptor antagonist; 0.5 mM or 50 mM/0.5 microl/side), or the glutamate receptor antagonists alone. Starting 7-10 days after the last pre-exposure injection, rats were trained to self-administer cocaine (0.3 mg/kg/infusion) and then tested under a progressive ratio (PR) schedule of reinforcement for 6 consecutive days. As reported previously, VTA AMPH pre-exposed rats worked more and obtained more infusions of cocaine than saline pre-exposed animals. Coadministration of CPP, CNQX, or MCPG with AMPH during pre-exposure dose-dependently blocked this enhancement of cocaine self-administration. Rats pre-exposed to the glutamate receptor antagonists alone did not differ on the test days from the saline pre-exposed controls. These results indicate that, in a manner paralleling the induction of sensitization of the locomotor stimulating effects of AMPH, activation of NMDA, AMPA/kainate, and mGlu receptors during pre-exposure to AMPH in the VTA is necessary for the enhancement of cocaine self-administration to develop. 相似文献