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Nagahama H Hatakeyama S Nakayama K Nagata M Tomita K Nakayama K 《Anatomy and embryology》2001,203(2):77-87
The cyclin-dependent kinase (CDK) inhibitors p27Kip1 and p57Kip2 are thought to regulate progression of the cell cycle. We have previously shown that the phenotypes of p27-/- mice are substantially different from those of p57-/- mice, suggesting that spatial and temporal expression patterns of p27Kip1 and p57Kip2 might be distinct. In this study, the roles of p27Kip1 and p57Kip2 in development were examined by characterizing their expression patterns during mouse embryogenesis by immunohistochemical analysis. Whereas certain organs and tissues (brain, lens, ganglion, lung, heart, liver, skin and kidney) expressed both proteins, others expressed only p27Kip1 (thymus, spleen, retina, testis and ovary) or only p57Kip2 (gut, palate, pancreas, cartilage and skeletal muscle). In addition, some organs expressed both p27Kip1 and p57Kip2 but showed mutually exclusive patterns of distribution among tissues. Thus, in the adrenal gland, p57Kip2 was expressed in the cortex but not in the medulla, whereas p27Kip1 was expressed in the medulla but not in the cortex. Whereas the expression of p57Kip2 in most tissues was restricted to embryogenesis, expression of p27Kip1 in many tissues was maintained in adult animals. Double-label immunofluorescence staining with either anti-p27Kip1 or anti-p57Kip2 and anti-BrdU revealed that the expression of p27Kip1 and p57Kip2 was inversely correlated with cell proliferation, suggesting that p27Kip1 and p57Kip2 are expressed exclusively in postmitotic cells. These complex spatial and temporal patterns of expression are consistent with the phenotypes of mice deficient in p27Kip1 or p57Kip2, and they suggest that these proteins might play important roles in tissue development. 相似文献
104.
Masayuki Nakayama Masashi Bando Tatsuya Hosono Hideaki Yamasawa Shoji Ohno Yukihiko Sugiyama 《Arerugī》2007,56(11):1384-1389
BACKGROUND: Our aim is to evaluate the significance of DLST by Shosaikoto. METHODS: We clinically evaluated 3 cases of drug-induced pneumonia assumed to be caused by Shosaikoto, and we performed DLST of Shosaikoto for healthy controls, and compared the data with drug-induced pneumonia cases of Shosaikoto. RESULTS: As clinical characteristics of 3 cases, 2 cases were positive for hepatitis C virus antibody, and 1 case was positive for DLST of Shosaikoto. The observed chest high-resolution CT (HRCT) findings showed hypersensitivity pneumonia (HP) pattern in all 3 cases. Prognosis was good in all 3 cases. DLST of Shosaikoto was positive in 27.5% of healthy controls. Stimulation index (S.I.) of DLST in drug-induced pneumonia cases increased depending on drug dilution density, compared to that of healthy controls. CONCLUSION: DLST of Shosaikoto showed high false-positive rate. However, we may be able to distinguish the true-positive cases with the false-positive cases by comparing the S.I. of DLST according to drug dilution density. 相似文献
105.
S Kageyama O Yamada S S Mohammad S Hama N Hattori M Asanaka E Nakayama T Matsumoto F Higuchi T Kawatani 《Journal of virological methods》1988,22(2-3):125-131
The measurement of HIV antigen levels in sera or plasma of HIV-infected individuals is critical for determining the existence of antigen or infectious virus before seroconversion and for prognosis. Pretreatment of sera or plasma of HIV carriers by heating at 70 degrees C for 10 min at an acidic pH enabled us to estimate antigens efficiently in immune complexes. This procedure will also be useful in determining antigen levels in HIV carriers more precisely. 相似文献
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Small cell carcinoma of the extrahepatic bile duct: case report and immunohistochemical analysis 总被引:2,自引:0,他引:2
Kuraoka K Taniyama K Fujitaka T Nakatsuka H Nakayama H Yasui W 《Pathology international》2003,53(12):887-891
A small cell carcinoma of the extrahepatic bile duct in a 75-year-old Japanese man is reported. The patient suffered from obstructive jaundice, and percutaneous transhepatic cholangiography-drainage (PTCD) revealed a massive lesion in the lower common bile duct. Because it was diagnosed as a malignant tumor, pancreaticoduodenectomy was performed. A nodular infiltrating tumor measuring 4.5 x 3.0 x 2.0 cm was located in the intrapancreatic portion of the extrahepatic bile duct. Histologically, the tumor was composed of a dense proliferation of small atypical cells with a little region of high-grade dysplasia in the adjacent epithelium of the common bile duct. Tumor cells were immunoreactive to neuroendocrine markers such as chromogranin A, synaptophysin, CD56, and Leu7. Although carcinoma cells invaded into pancreas and duodenum, there were no histological findings that indicated the carcinoma arose from the mucosa of either the pancreatic duct or duodenum. These results indicated that the tumor was a small cell carcinoma derived from the epithelium of the extrahepatic bile duct; a rare neoplasm with only a few cases reported. A few neuroendocrine cells were recognized in the adjacent epithelium of the extrahepatic bile duct, suggesting that the tumor cells might be derived from them. Using immunohistochemical examination, no p53 abnormality was found. Tumor cells showed positive nuclear staining for p16, while negative for cyclin D1, suggesting that functional retinoblastoma protein (pRB) might be lost in the p16/pRB pathway, as in small cell lung cancer. 相似文献
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Shigeo Nagasaka Shigeki Taniguchi Yoshio Nakayama Hidehito Sakaguchi Kazuhiko Nishizaki Hiroshi Naito Hiroyuki Morioka 《Cardiovascular pathology》2005,14(2):70-79
BACKGROUND: Recent reports have suggested that cryopreservation reduces the immunogenicity of donor tissue. The immunomodulation by cryopreservation might influence on the tissue durability after xenotransplantation. We investigated the in vivo morphologic changes in cryopreserved xenograft (CXG) heart valves. MATERIAL AND METHOD: We transplanted a fresh (fresh xenograft; FXG) and a cryopreserved (CXG) porcine aortic root and a cryopreserved canine (cryopreserved allograft; CAG) aortic root into the abdominal aorta of a dog without any immunosuppressive agents. Explanted grafts on the 21st to 49th days after implantation were analyzed morphologically with light microscopy using some special stains, immunohistochemical analysis, and scanning electron microscopy (SEM). RESULT: Light microscopy showed the absence of smooth muscle cells in the media of the aorta in any group after transplantation. FXG valves did not maintain any cellularity after transplantation. CXG valves contained cellular infiltration in themselves. CAG valves contained numerous fibroblasts, which showed the maintenance of tissue integrity without allowing cellular infiltration. The structure of elastic fibers was well maintained, even in the part of CXG valve with cellular infiltration. Immunohistochemical studies documented the infiltration of T lymphocytes in CXG valves that were labeled by anti-CD3 antibodies. SEM demonstrated that no endothelia were seen on the surface of the valves in any group after transplantation. CONCLUSION: We concluded that the cryopreservation method might provide an immunomodulation of xenogeneic heart valves for transplantation. 相似文献