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71.
Osamu Sakai Yasuhide Nakayama Yasushi Nemoto Yoshihiro Okamoto Taiji Watanabe Keiichi Kanda Hitoshi Yaku 《Journal of artificial organs》2005,8(2):119-124
A novel sutureless vascular connecting system, an assembly with a delivery rod, an introducing sheath, and a connecting device, was developed for easy implantation of small-caliber vascular grafts less than 2 mm in internal diameter. A microporous stainless tube (length 2 mm, external diameter 1.6 mm, wall thickness 65 µm, pore diameter 400 µm, pore-to-pore distance 500 µm) was designed to serve as a connecting device. The feasibility of the system was tested using two types of preliminary animal experiments. One animal model consisted of graft implantation into the rat abdominal aorta (1.5 mm in diameter). The connecting device was inserted into the proximal and distal ends of the aorta through the introducing sheath by pushing the delivery rod with the connecting device placed over it. Subsequently, the aortic segments were inserted into both ends of model grafts made of segmented polyurethane (1.8 mm in internal diameter) and were fixed with banding silk threads from the exterior. The procedure was completed within 20 min without requiring specialized microsurgery techniques. Blood leakage and obstruction did not occur. The second model consisted of an end-to-end anastomosis between rabbit common carotid arteries (2 mm in diameter), which was performed within several minutes of blood flow interruption. Scanning electron microscopy demonstrated that the luminal surface of the device was fully covered with endothelial cells (ECs) after 1 week as a result of transluminal ingrowth of native ECs through the micropores in the device. This endothelialization may prevent early thrombus-induced occlusion. This simple and “easy-to-learn” technique will promote the development of small-caliber arterial grafts, and furthermore, it may have potential for clinical application. 相似文献
72.
Miwa N Hayakawa S Miyazaki S Myojo S Sasaki Y Sakai M Takikawa O Saito S 《Molecular human reproduction》2005,11(12):865-870
Recent data demonstrated that CD4+CD25+ regulatory T (Treg) cells and an enzyme called indoleamine 2,3-dioxygenase (IDO) mediate maternal tolerance to the fetus. Interestingly, Treg cells express the CTLA-4 molecule on their surface, and B7 (CD80/86) ligation by CTLA-4 enhanced IDO activity of dendritic cells (DCs) and monocytes by the induction of interferon gamma (IFN-gamma) production. In this study, we studied the IDO expression on peripheral blood monocytes and decidual monocytes or DCs after treatment with CTLA-4/Fc fusion protein or IFN-gamma using flow cytometry. IDO expressions on both peripheral blood DC and decidual DC and monocytes were up-regulated during normal pregnancy. On the other hand, both IDO expression on DC and monocytes after IFN-gamma treatment or CTLA-4 treatment were decreased in spontaneous abortion cases. The expression of CD86 on peripheral blood and decidual monocytes and DC in spontaneous abortion cases was lower compared with those in normal pregnancy subjects. Also, IFN-gamma production by decidual and peripheral blood mononuclear cells after CTLA-4/Fc treatment in spontaneous abortion cases was significantly lower than those in normal pregnancy subjects. These data suggest that CTLA-4 on Treg cells up-regulates IDO expression on decidual and peripheral blood DC and monocytes by the induction of IFN-gamma production. 相似文献
73.
74.
The aim of this study was to examine if adhesion molecules had relation with degeneration and regeneration processes of mammalian vestibular epithelia. The distribution of E-cadherin and beta-catenin was immunohistochemically examined in normal and aminoglycoside-treated utricles of mice. E-cadherin and beta-catenin linearly expressed between epithelial cells in normal specimens. Aminoglycoside injury resulted in temporal alteration in distribution of these molecules with induction of apoptosis in hair cells. Degradation of both molecules was widely observed in vestibular epithelia, while some supporting cells exhibited accumulation of beta-catenin. After completion of induction of apoptosis, expression of these adhesion molecules was normal in distribution. These findings suggest that the E-cadherin-beta-catenin complex plays roles in degeneration and subsequent repair processes in vestibular epithelia affected by aminoglycosides. 相似文献
75.
Rapid and efficient generation of lentivirally gene-modified dendritic cells from DC progenitors with bone marrow stromal cells 总被引:4,自引:0,他引:4
Sumimoto H Tsuji T Miyoshi H Hagihara M Takada-Yamazaki R Okamoto S Ikeda Y Takahashi T Kawakami Y 《Journal of immunological methods》2002,271(1-2):153-165
Since dendritic cells (DC) play pivotal roles in both innate and adaptive immunity, DC can be a good target for immuno-gene therapy. However, the optimal generation method for gene-modified DC has not yet been well exploited. CD34+ cells from cord blood (CB), bone marrow (BM), or peripheral blood (PB) were expanded in a medium containing stem cell factor (SCF), flt 3 ligand (Flt3L) and thrombopoietin (TPO) with or without HESS-5, a murine BM stromal cell line, for 2 weeks (the first expansion step), then differentiated to DC in a medium containing granulocyte-macrophage colony-stimulating factor (GM-CSF), flt 3 ligand (Flt3L), stem cell factor (SCF), tumor necrosis factor-alpha (TNF-alpha), IL-4, and lipopolysaccharide (LPS) for 9 days (the second differentiation step). DC progenitors were transduced with human immunodeficiency virus (HIV) vectors at different time points during the second step. Use of HESS-5 during the first step resulted in more DC generation than without it (cell expansion: CB, 10,461 vs. 354-fold; BM, 962 vs. 225-fold; peripheral blood mononuclear cell (PBMC), 8,506 vs. 240-fold; %DC: CB, 83.4% vs. 76.9%; BM, 83.6 vs. 69.8%; PBMC, 85.9 vs. 60.5%). Gene transduction to the in vitro expanded DC progenitors at day 3 during the second step, resulted in better final yield of the gene-modified DC than that to those at day 0 or day 6 (as much as 44% of DC expressed green fluorescence protein (GFP) as a transgene) and the transduction efficiency correlated with endocytic ability and percent of S phase. DC transduced with an HIV vector encoding a melanoma antigen, MART-1, were adequately recognized by specific anti-MART-1 CTL. The two-step culture method with HESS-5 is useful for rapid expansion of DC progenitors and subsequent lentiviral gene transduction to DC. 相似文献
76.
Naoko Udaka Takaaki Ito Yasushi Sato Masayoshi Kanisawa Shinobu Satoh 《Brain structure & function》1995,192(5):399-406
The expression of gap junction protein was examined immunohistochemically using affinity-purified antibody against rat liver gap junction protein, connexin 32 (Cx32), in the kidneys of fetal (gestation days 13–16) and adult Syrian golden hamsters. Phalloidin histochemical staining, PNA- and RCA I-lectin stainings, NCAM immunostaining, and alkaline phosphatase and Na+-K+-ATPase enzyme-histochemical staining were performed in combination with Cx32 immunostaining. The kidney sections were observed with a confocal scanning laser microscope. By gestation day 13, Cx32 immunoreactivity was observed in the differentiating tubules. The Cx32 staining was localized on the lateral cell membrane of the cells lining the developing proximal tubules, while the S-shaped bodies, developing distal tubules, and collecting tubules showed no positive immunostaining. As the kidney developed, the density of Cx32 immunoreactivity increased. As the gap junction provides pathways for cell-cell communication, the development of Cx32 expression may imply that this structure plays an important role in renal tubule development. Confocal scanning laser microscopy provided a clear image of the fluorescence-labeled cell structures, free from out-of-focus blur. Using the same sections, stereoscopic images were easily reconstructed from serial optical sections, and were helpful in understanding the spatial distribution of Cx32 expression in the developing fetal proximal tubules. 相似文献
77.
78.
Role of p27Kip1 and Cyclin-Dependent Kinase 2 in the Proliferation of Non-Small Cell Lung Cancer 总被引:12,自引:0,他引:12
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Hidetada Kawana Jun-ichi Tamaru Tomoaki Tanaka Aizan Hirai Yasushi Saito Masatoshi Kitagawa Atsuo Mikata Kenichi Harigaya Takayuki Kuriyama 《The American journal of pathology》1998,153(2):505-513
The cell cycle is governed by a family of cyclin-dependent kinases (Cdks). Cdk2 forms a functional complex with cyclin E and plays a pivotal role in the regulation of G1/S transition. Cdk2 activity is negatively regulated by interactions with inhibitors. p27Kip1, one of the most potent inhibitors of Cdk2, was recently identified as a powerful negative prognostic marker in non-small cell lung cancer as well as in colorectal and breast cancer. In the present study, the expression of p27 and Ki-67 antigen in nonneoplastic and cancerous lung tissues was determined by immunohistochemistry. After establishing that the antibody-measured p27 labeling index was a good reflection of the level of p27 expression measured by Western blotting, we show that p27 labeling index is decreased in cancerous lung tissues, compared with nonneoplastic lung tissues, and exhibits a significant inverse relation to the proliferation marker Ki-67 antigen, detected with monoclonal antibody MIB-1. Consistent with these data, all cancerous lung tissues showed enhanced degradation activity of p27 compared with nonneoplastic lung tissues and, in addition, increased levels of the phosphorylated form of Cdk2, as determined with Western blot analysis. The H1 histone kinase activity associated with Cdk2 was also increased in non-small cell lung cancers. Statistical analysis showed that proliferative activity as measured by MIB-1 labeling index was highly correlated with Cdk2 activity (r = 0.767, P < 0.0015). These results suggest that p27 and Cdk2 may play an important role in the proliferation of non-small cell cancer. 相似文献
79.
Satoh Y Ishikawa Y Miyoshi T Mukai H Okumura S Nakagawa K 《Virchows Archiv : an international journal of pathology》2003,442(2):173-178
Pulmonary metastasis from low-grade endometrial stromal sarcomas (ESSs) occasionally are found after long, disease-free periods, mostly as incidental histological or radiological discoveries. We describe a case of low-grade ESS presenting as nodular pulmonary metastases finally diagnosed by estrogen-receptor staining, cytogenetic and fluorescence in situ hybridization (FISH) analyses, and perusal of the histology of hysterectomy material. An abnormal nodule in the lung field was discovered by means of chest X-ray of a 47-year-old woman. She had been disease free for 13 years after hysterectomy for an alleged leiomyoma. A computed tomographic scan revealed nodules, with fluctuation in size over the 2-year period, in both lungs. Finally the lesion in the left lung was resected, and pulmonary endometriosis was suspected because of the lack of stromal cell nuclear atypia and positive immunohistochemical reactions for estrogen and progesterone receptors. However, a characteristic karyotype was identified cytogenetically: 46, XX, t(7;17)(p15;q11), the translocation of which, specific to ESS, was confirmed by FISH analysis. A final diagnosis of pulmonary metastases from an ESS could be made by reviewing the histology of the previous uterine tumor. In this case, metastatic lesions from an ESS showed a decrease as well as an increase in size, despite the malignant potential. Immunostaining for estrogen and progesterone receptors and cytogenetic and FISH analyses, together with clinical information on the past gynecological history, are valuable diagnostic keys. 相似文献
80.