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101.
Cardiac ankyrin repeat protein (CARP), which is structurally characterized by the presence of four ankyrin repeat motifs in its central region, is believed to be localized in the nucleus and to participate in the regulation of cardiac-specific gene expression in cardiomyocytes. However, we recently found that CARP was induced in skeletal muscle by denervation, leading us to speculate that CARP may be induced under some pathological conditions. In the present study, we immunohistochemically analyzed the expression of CARP in 11 cases of spinal muscular atrophy (SMA) and 14 cases of congenital myopathy. In SMA, CARP was expressed selectively in severely atrophic myofibers, suggesting that CARP expression may reflect the status of muscle atrophy. Furthermore, in the congenital myopathies, the expression patterns of CARP were distinct among the subtypes, which included nemaline myopathy, myotubular myopathy, central core disease, and congenital fiber type disproportion. Although CARP was preferentially expressed in severely damaged myofibers in nemaline myopathy, it was not detected in central core disease. These findings suggest that immunohistochemical evaluation of CARP may be helpful in the diagnosis of SMA and the congenital myopathies. 相似文献
102.
Kaira K Oriuchi N Imai H Shimizu K Yanagitani N Sunaga N Hisada T Kawashima O Iijima H Ishizuka T Kanai Y Endou H Nakajima T Mori M 《Pathology, research and practice》2008,204(8):553-561
Amino acid transport systems play an important role in cellular proliferation. L-type amino acid transporter 1 (LAT1) has been associated with tumor growth, and is highly expressed in the established tumor cell lines and primary human neoplasms. In this study, we investigated the expression of LAT1 to evaluate the malignant potential and prognostic significance in neuroendocrine (NE) tumors of the lung. Twenty-one surgically resected, large cell neuroendocrine carcinomas (LCNEC), 13 small cell lung cancers (SCLC), five atypical carcinoids (AC), and 10 typical carcinoids (TC) were enrolled in the study. LAT1 expression and Ki-67 labeling index of the NE tumors were analyzed by immunohistochemical staining. LAT1 was overexpressed in 52.4% of the LCNEC, in 46.2% of the SCLC, and in 25% of the AC. LAT1 expression in LCNEC was significantly associated with lymph node metastasis and poor outcome. Moreover, a significant correlation was found between LAT1 expression and Ki-67 in both LCNEC and SCLC. Expression of LAT1 tended to increase from low-grade to high-grade NE tumors. The present results suggest that LAT1 may play a significant role in cellular proliferation, lymph node metastasis, and poor outcome in patients with NE tumors of the lung. 相似文献
103.
Hypoxic preconditioning augments efficacy of human endothelial progenitor cells for therapeutic neovascularization 总被引:17,自引:0,他引:17
Akita T Murohara T Ikeda H Sasaki K Shimada T Egami K Imaizumi T 《Laboratory investigation; a journal of technical methods and pathology》2003,83(1):65-73
A subset of human peripheral blood mononuclear cells (PB-MNCs) differentiate into endothelial progenitor cells (EPCs) that participate in postnatal neovascularization. Although tissue ischemia can mobilize EPCs from bone marrow, the effects of hypoxia on differentiation and angiogenic function of EPCs are little known. We examined whether hypoxic conditioning would modulate differentiation and function of human PB-MNC-derived EPCs. A subset of PB-MNCs gave rise to EPC-like attaching (AT) cells under either normoxic or hypoxic conditions. However, hypoxia much enhanced the differentiation of AT cells from PB-MNCs compared with normoxia. AT cells released vascular endothelial growth factor (VEGF) protein and expressed CD31 and kinase insert domain receptor/VEGFR-2, endothelial lineage markers, on their surface, which were also enhanced by hypoxia. Both a neutralizing anti-VEGF mAb and a KDR-specific receptor tyrosine kinase inhibitor, SU1498, suppressed PB-MNC differentiation into EPC-like AT cells in a dose-dependent manner. Migration of AT cells in response to VEGF as examined by a modified Boyden chamber apparatus was also enhanced by hypoxia. Finally, in vivo neovascularization efficacy was significantly enhanced by in vitro hypoxic conditioning of AT cells when cells were transplanted into the ischemic hindlimb of immunodeficient nude rats. In conclusion, hypoxia directly stimulated differentiation of EPC-like AT cells from human PB-MNC culture. Moreover, hypoxic preconditioning of AT cells before in vivo transplantation is a useful means to enhance therapeutic vasculogenesis. 相似文献
104.
Katsumata Maai Yoshikawa Hisao Tokoro Masaharu Mizuno Tetsushi Nagamoto Takehiro Hendarto Joko Asih Puji B.S. Rozi Ismail E. Kimata Isao Takami Kazutoshi Syafruddin Din 《Parasitology research》2018,117(9):2841-2846
Parasitology Research - Blastocystis sp. is a common intestinal protist found worldwide in a variety of animals, including humans. Currently, 17 subtypes (STs) of Blastocystis isolates from... 相似文献
105.
Tetsuji Mori Taketoshi Wakabayashi Yasuharu Takamori Kotaro Kitaya Hisao Yamada 《ACTA HISTOCHEMICA ET CYTOCHEMICA》2009,42(1):1-8
In intact adult mammalian brains, there are two neurogenic regions: the subependymal zone and the subgranular layer of the hippocampus. Even outside these regions, small numbers of proliferating precursors do exist. Many studies suggest that the majority of these are oligodendrocyte precursors that express NG2, a chondroitin sulfate proteoglycan, and most of the residual proliferating cells seem to be endothelial cells. However, it is still unclear whether NG2-immunonegative proliferating precursors are present, because previous studies have neglected their possible existence. In this study, we systematically analyzed the phenotypes of the proliferating cells in the intact adult rat cortical gray matter. We improved our techniques and carefully characterized the proliferating cells, because there were several problems with identifying and quantifying the proliferating cells: the detection of NG2-expressing cells was dependent on the fixation condition; there were residual proliferating leukocytes in the blood vessels; and two anti-NG2 antibodies gave rise to different staining patterns. Moreover, we used two methods, BrdU and Ki67 immunostaining, to quantify the proliferating cells. Our results strongly suggest that in the intact adult cerebral cortical gray matter, there were only two types of proliferating cells: the majority were NG2-expressing cells, including pericytes, and the rest were endothelial cells. 相似文献
106.
Hiroshi Tanaka Yumiko Kubota Tsuyoshi Tsujimura Maya Kumano Hisao Masai Haruhiko Takisawa 《Genes to cells : devoted to molecular & cellular mechanisms》2009,14(8):949-963
Cohesin-mediated sister chromatid cohesion is established during the S-phase, and recent studies demonstrate that a cohesin protein ring concatenates sister DNA molecules. However, little is known about how DNA replication is linked to the establishment of sister chromatid cohesion. Here, we used Xenopus egg extracts to show that AND-1 and Tim1–Tipin, homologues of Saccharomyces cerevisiae Ctf4 and Tof1–Csm3, respectively, are associated with the replisome and are required for proper establishment of the cohesion observed in the M-phase extracts. Immunodepletion of both AND-1 and Tim1–Tipin from the extracts leads to aberrant sister chromatid cohesion, which is similarly induced by the depletion of cohesin. These results demonstrate that AND-1 and Tim1–Tipin are key factors linking DNA replication and establishment of sister chromatid cohesion. On the basis of the physical interactions between AND-1 and DNA polymerases, we discuss a model to describe how replisome progression complex establishes sister chromatid cohesion. 相似文献
107.
Hisao Yoshida MD Shigenori Kusuki MD Yoshiko Hashii MD PhD Hideaki Ohta MD PhD Tomohiro Morio MD PhD Keiichi Ozono MD PhD 《Pediatric blood & cancer》2009,52(7):895-897
High‐risk neuroblastoma has a poor prognosis despite multimodal treatment including high‐dose chemotherapy. A 7‐year‐old male with neuroblastoma received ex vivo‐expanded donor CD4+ T lymphocyte infusion (CD4+ DLI) after recurrence in the bone marrow following allogeneic hematopoietic stem cell transplantation from his HLA‐identical mother. The disease transiently responded to CD4+ DLI with reduction of tumor cells and a decrease of serum neuron‐specific enolase. The response was associated with development of continued high fever and an increase of cytotoxic T lymphocytes in peripheral blood. This case suggests a possibility of a graft‐versus‐tumor effect against neuroblastoma. Pediatr Blood Cancer 2009;52:895–897. © 2009 Wiley‐Liss, Inc. 相似文献
108.
109.
Honma K Abraham JL Chiyotani K De Vuyst P Dumortier P Gibbs AR Green FH Hosoda Y Iwai K Williams WJ Kohyama N Ostiguy G Roggli VL Shida H Taguchi O Vallyathan V 《Human pathology》2004,35(12):1515-1523
We defined mixed-dust pneumoconiosis (MDP) pathologically as a pneumoconiosis showing dust macules or mixed-dust fibrotic nodules (MDF), with or without silicotic nodules (SN), in an individual with a history of exposure to mixed dust. We defined the latter arbitrarily as a mixture of crystalline silica and nonfibrous silicates. According to our definition of MDP, therefore, MDF should outnumber SN in the lung to make a pathologic diagnosis of MDP. In the absence of confirmation of exposure, mineralogic analyses can be used to support the pathologic diagnosis. The clinical diagnosis of MDP requires the exclusion of other well-defined pneumoconioses, including asbestosis, coal workers’ pneumoconiosis, silicosis, hematite miners’ pneumoconiosis, welders’ pneumoconiosis, berylliosis, hard metal disease, silicate pneumoconiosis, diatomaceous earth pneumoconiosis, carborundum pneumoconiosis, and corundum pneumoconiosis. Typical occupations associated with the diagnosis of MDP include metal miners, quarry workers, foundry workers, pottery and ceramics workers, and stonemasons. Irregular opacities are the major radiographic findings in MDP (ILO 1980), in contrast to silicosis, in which small rounded opacities predominate. Clinical symptoms of MDP are nonspecific. MDP must be distinguished from a variety of nonoccupational interstitial pulmonary disorders. 相似文献
110.