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81.
82.
Bernhard U. Zabel Susan L. Naylor Karl-Heinz Grzeschik Alan Y. Sakaguchi 《Somatic Cell and Molecular Genetics》1984,10(1):105-108
Using human-mouse somatic cell hybrids containing different parts of chromosome 6 and a DNA probe of the oncogene (V-myb) of avian myeloblastosis virus (AMV), we regionally mapped by Southern blot techniques the human cellular myb (cmyb) protooncogene to 6q21qter. 相似文献
83.
Keiichi Tamai Masafumi Toyoshima Nobuyuki Tanaka Noriko Yamamoto Yuji Owada Hiroshi Kiyonari Kazuko Murata Yoshiyuki Ueno Masao Ono Tooru Shimosegawa Nobuo Yaegashi Masahiko Watanabe Kazuo Sugamura 《The American journal of pathology》2008,173(6):1806-1817
The endosomal sorting complex required for transport (ESCRT) proteins form multimolecular complexes that control multivesicular body formation, endosomal sorting, and transport ubiquitinated membrane proteins (including cell-surface receptors) to the endosomes for degradation. There is accumulating evidence that endosomal dysfunction is linked to neural cell degeneration in vitro, but little is known about the relationship between neural disorders and ESCRT proteins in vivo. Here we specifically deleted the hrs gene, ESCRT-0, in the neurons of mice by crossing loxP-flanked hrs mice with transgenic mice expressing the synapsin-I Cre protein (SynI-cre). Histological analyses revealed that both apoptosis and a loss of hippocampal CA3 pyramidal neurons occurred in the hrsflox/flox;SynI-cre mice. Notably, the hrsflox/flox;SynI-cre mice accumulated ubiquitinated proteins, such as glutamate receptors and an autophagy-regulating protein, p62. These molecules are particularly prominent in the hippocampal CA3 neurons and cerebral cortex with advancing age. Accordingly, we found that both locomotor activity and learning ability were severely reduced in the hrsflox/flox;SynI-cre mice. These data suggest that Hrs plays an important role in neural cell survival in vivo and provide an animal model for neurodegenerative diseases that are known to be commonly affected by the generation of proteinaceous aggregates. 相似文献
84.
Expression of cyclin D1, retinoblastoma gene protein, and p16 MTS1 protein in atypical adenomatous hyperplasia and adenocarcinoma of the lung 总被引:2,自引:0,他引:2
Y. Kurasono Takaaki Ito Yoichi Kameda Nobuo Nakamura Hitoshi Kitamura 《Virchows Archiv : an international journal of pathology》1998,432(3):207-215
To clarify the events leading to the disruption of cell growth control that occurs during the development of pulmonary adenocarcinoma
(AC), we used immunohistochemistry to evaluate the expression of G1 cycle regulators, cyclin D1, Rb protein (pRb), and p16
MTS1 protein and the tumour proliferation marker, Ki 67, both in AC of the lung and in its precursor lesion, atypical adenomatous
hyperplasia (AAH). The frequency of lesions with cyclin D1 overexpression was relatively high in AAH (47–89%), but was decreased
in early AC (28%) and overt AC (35%). The loss of pRb expression was rare in both AAH (0–18%) and early AC (0%), and was infrequent
even in overt AC (13%). The loss of p16 expression was also relatively infrequent in both the premalignant and the malignant
lesions (11–25%). Our results suggest that overexpression of cyclin D1 is an early event and plays an important part in tumorigenesis
in the case of lung AC. However, cyclin D1 overexpression is not required for the development and maintenance of a malignant
phenotype. It is likely that some cyclin D1-independent pathways other than Rb and p16 abnormalities have an important role
in the malignant transformation from AAH to early AC.
Received: 8 July 1997 / 26 September 1997 相似文献
85.
Yasuhiko?IwasakiEmail author Nobuo?Nakabayashi Kazuhiko?Ishihara 《Journal of artificial organs》2003,6(4):260-266
To identify the advantages of 2-methacryloyloxyethyl phosphorylcholine (MPC) copolymer-coated polysulfone (PSf) hollow fibers for hemodialyzer and hemofilter minimodules with hollow fibers were made and blood compatibility was evaluated in vitro and ex vivo. Three types of hollow fibers, i.e., pure PSf (no additives), PSf alloyed with poly(1-vinyl-2-pyrrolidone) (PVPy), and PSf coated with the MPC copolymer, were processed in wet conditions. Commercially available hollow fibers (APS) were used as a control sample. The PSf hollow fibers have a condensed structure. A porous structure was observed when the PVPy was alloyed before wet processing, and no effect of the innercoated MPC copolymer on the porous structure was observed. One-tenth-sized minimodules of the conventional hemodialyzer were fabricated with 200 fibers each. The solute permeability of the hollow fibers was evaluated using 10% bovine serum in a buffer solution containing cytochrome C, which is a model protein of 2-microglobulin. After circulation for 2.5h, the solute permeability of APS and PVPy-alloyed PSf hollow fibers decreased to 50% compared with their initial values. In contrast, the value for the hollow fibers innercoated with the MPC copolymer maintained its initial level. The inner surface of the dialysis membranes was observed with a transmission electron microscope and a layer of adsorbed protein on the PSf, APS, and PVPy-alloyed PSf hollow fibers was observed, but not on the MPC copolymer-coated fibers. Blood cell adhesion was then evaluated by circulation of whole rabbit blood without any anticoagulant ex vivo. Many adherent cells were observed on the PVPy-alloyed PSf hollow fibers; however, blood cells did not adhere or aggregate on the MPC copolymer-coated hollow fibers. From these results, we concluded that the in-situ coating of MPC copolymer on PSf hollow fibers is effective in preventing blood coagulation and maintaining the solute permeability of the fibers. 相似文献
86.
Haruo Hagiwara Nobuo Ohwada Takeo Aoki Takeshi Suzuki Kuniaki Takata 《Medical molecular morphology》2008,41(4):221-226
Stromal cells in the lamina propria of the human oviduct mucosa are unique cells that can differentiate into decidual cells
during ectopic pregnancy in the oviduct. The nature of stromal cells is still unknown. In the present study, we investigated
human oviductal stromal cells with transmission electron microscopy and immunohistochemistry and revealed that they had ultrastructural
features similar to myofibroblasts and expressed alpha-smooth muscle actin, a marker used to identify myofibroblasts. Primary
cilia were also one of the characteristic profiles of the stromal cells. These findings showed that the connective tissue-stromal
cells in the human oviduct mucosa are myofibroblasts. They are considered to play an important role in the transport of oocytes
by bringing about contraction of the mucosal folds. 相似文献
87.
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
88.
Nobuo Takeshima Kiyoji Tanaka Fumio Kobayashi Takemasa Watanabe Takashi Kato 《European journal of applied physiology》1993,67(2):138-143
Summary In this study we attempted to determine the effects of exercise training at the intensity corresponding to lactate threshold (Thla
–) on various health-related variables in sedentary but apparently healthy elderly subjects. Six men and five women volunteers [mean age 68.9 (SD 3.4) years] performed supervised endurance-type training on stationary cycle ergometers for 30 min and recreational activities for 30 min, 3 days a week for 12 weeks. Four men and four women served as the control group [68.8 (SD 4.4) years]. As a result of the training programme, statistically significant increases in maximal oxygen consumption (10%), oxygen consumption at Thla
–(18%), distance covered in 12-min walk, side step, and leg extensor power were found in the training group, while no changes occurred in the control group. The changes in serum cholesterol and triglyceride concentrations from the pre- to post-training period were statistically significant. High-density lipoprotein cholesterol remained unchanged, and low-density lipoprotein cholesterol tended to decrease following the training programme. These data would indicate that exercise training at the intensity corresponding to Thla
–may have favourable effects on overall physical fitness and some serum lipid variables in older individuals. 相似文献
89.
Extracellular ATP stimulated histamine release and generation of leukotrience C4 (LTC4) accompanied with the formation of inositol phosphates and a rapid increase in intracellular Ca2+ ([Ca2+]i) in mouse bone marrow-derived cultured mast cells (BMMC). The rank order of histamine-releasing potency of ATP and its metabolites is ATP greater than ADP greater than AMP greater than adenosine. Nonhydrolyzable ATP analog, adenosine-5'-O-[2-thiotriphosphate] (ATP-S) released more histamine from the cells than ATP. On the other hand, simultaneous addition of adenosine analogues at micromolar concentrations potentiated histamine release from the cells induced by ATP (50 microM) or DNP-HSA antigen (0.1 ng/ml) in the following rank order: adenosine greater than AMP much greater than ADP = ATP. Histamine release potentiated by adenosine was blocked by the treatment with pertussis toxin, whereas histamine release induced by ATP was not affected by the toxin, suggesting that extracellular ATP stimulate histamine release from BMMC probably via mechanisms independent of the potentiation of histamine release induced by adenosine. 相似文献
90.