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991.
Mutational analysis of Noxa gene in human cancers   总被引:4,自引:0,他引:4  
There has been mounting evidence that dysregulation of apoptosis is involved in the mechanisms of cancer development and somatic mutations of apoptosis-related genes have been reported in human cancers. Noxa, a Bcl-2 homology 3 (BH3)-only member of the Bcl-2 family, is known to interact with anti-apoptotic Bcl-2 family members and induces apoptosis. The aim of this study was to explore the possibility that the Noxa gene is mutated in human cancers. We have analyzed the entire coding region and all splice sites of the Noxa gene for the detection of somatic mutations in a series of human cancers, including carcinomas from stomach, colon, liver, urinary bladder and lung by polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP), and DNA sequencing. We found one somatic mutation of the Noxa gene in a transitional cell carcinoma (TCC) of the urinary bladder. To evaluate the functional alterations of the mutant in apoptosis, we overexpressed the mutant and wild-type Noxa in 293T and HeLa cells, but could not find any significant difference in cell death between the wild-type and mutant Noxa. These data suggest that Noxa is rarely mutated in human carcinomas and that the contribution of Noxa gene mutation in the pathogenesis of human cancer might not be related to cell death mechanisms.  相似文献   
992.
Mutational analysis of Fas ligand gene in human non-Hodgkin lymphoma   总被引:2,自引:0,他引:2  
Among the systems triggering apoptosis, the Fas-Fas ligand (FasL) system is recognized as a major pathway for the induction of apoptosis in cells and tissues. Ligation of Fas by either an agonistic antibody or FasL transmits a 'death signal' to the target cell, potentially triggering apoptosis. Alterations of genes along the Fas-mediated apoptosis pathway have been reported in many human cancers. However, there have been no data regarding FasL gene mutations in human cancers. We hypothesized that FasL gene mutation might be involved in the development of non-Hodgkin lymphoma (NHL). In this study, we analyzed the entire coding region of the FasL gene for the detection of somatic mutations in a series of 111 NHLs and found that one tumor had a FasL gene mutation in the cytoplasmic domain. To evaluate the functional alterations of the mutant in apoptosis, we overexpressed the mutant in 293T cells, but couldn't find any significant loss of cell death compared to the wild-type FasL. Together, these data suggest that FasL is occasionally mutated in human NHL and that FasL mutations appear to play no role in the pathogenesis of the vast majority of NHLs.  相似文献   
993.

Purpose  

This prospective study was performed to evaluate the effect of chemotherapy-related neurotoxicity on quality of life (QOL) of patients with lymphoma.  相似文献   
994.
Detection of autoantibodies against tumor‐associated antigens (TAA) has recently been shown to be a powerful tool for early detection of various cancers. The aim of this study was to investigate the possibility of using autoantibodies against TAA as novel biomarkers by a proteomics‐based approach in patients with ovarian cancer. We used two‐dimensional differential gel electrophoresis analysis of immuno‐precipitated tumor antigens (2D‐DITA) to compare the levels of autoandibodies in pretreatment and posttreatment sera of patients with ovarian cancers. The identified autoantibodies were validated by SYBR Green real‐time polymerase chain reaction (PCR) and immunohistochemistry (IHC). We further evaluated the level of autoantibody in sera of 68 ovarian cancer patients by an enzyme‐linked immunosorbent assay (ELISA). The autoantibody directed against stress‐induced phosphoprotein‐1 (STIP‐1) emerged as a novel biomarker candidate for ovarian cancer. SYBR Green PCR and IHC confirmed that the STIP‐1 mRNA and protein expression levels were significantly up‐regulated in ovarian cancers compared with normal and benign tumors (P = 0.003 and P < 0.001, respectively). A preliminary ELISA study showed that the serum levels of anti‐STIP‐1 autoantibodies were significantly elevated in ovarian cancer patients compared with healthy controls (P = 0.03). The results suggest that 2D‐DITA is a useful tool to detect autoantibodies and that STIP‐1 is a potential biomarker candidate for ovarian cancers. © 2010 Wiley‐Liss, Inc.  相似文献   
995.
The bony septum ossifies from cranial to caudal and from ventral to dorsal, thereby forming the perpendicular plate of ethmoid bone and vomer. A small strip of cartilage from the cartilaginous septum remains between these parts, the so‐called sphenoidal process of the cartilaginous septum. This sphenoidal process is usually seen at the top of a deviated nasal septum during septoplasty. This study evaluated the clinical significance of the sphenoidal process of the cartilaginous septum as a cause of nasal septal deviation. We studied 37 patients with septal deviation who underwent septoplasty. The complex consisting of the sphenoidal process of the cartilaginous septum, perpendicular plate of the ethmoid bone (PPE), and vomer was removed at surgery. The sphenoidal process was measured and the surgical specimen were evaluated histologically and compared to controls. The mean length of the sphenoidal process in patients with a deviated nasal septum was 26.05 ± 5.32 mm versus 11.95 ± 2.38 mm in controls. The sphenoidal process was significantly longer in the patients with a deviated nasal septum (P < 0.05). The sphenoidal process of the cartilaginous septum was connected to the PPE and vomer in the patients with a deviated nasal septum and differed histologically from that of the controls. The sphenoidal process of the cartilaginous septum was long and prominent in the patients with septal deviation, implying that delayed nasal septal ossification may be one cause of nasal septal deviation. Clin. Anat. 23:265–269, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
996.
Pregnenolone sulfate (PS) acts as an excitatory neuromodulator and has a variety of neuropharmacological actions, such as memory enhancement and convulsant effects. In the present study, we investigated the effect of PS on glutamatergic spontaneous excitatory postsynaptic currents (sEPSCs) in acutely isolated dentate gyrus (DG) hilar neurons by use of a conventional whole-cell patch-clamp technique. PS significantly increased sEPSC frequency in a concentration-dependent manner without affecting the current amplitude, suggesting that PS acts presynaptically to increase the probability of spontaneous glutamate release. However, known molecular targets of PS, such as α7 nicotinic ACh, NMDA, σ1 receptors and voltage-dependent Ca2+ channels, were not responsible for the PS-induced increase in sEPSC frequency. In contrast, the PS-induced increase in sEPSC frequency was completely occluded in a Ca2+-free external solution, and was significantly reduced by either the depletion of presynaptic Ca2+ stores or the blockade of ryanodine receptors, suggesting that PS elicits Ca2+-induced Ca2+ release (CICR) within glutamatergic nerve terminals. In addition, the PS-induced increase in sEPSC frequency was completely occluded by transient receptor potential (TRP) channel blockers. These data suggest that PS increases spontaneous glutamate release onto acutely isolated hilar neurons via presynaptic CICR, which was triggered by the influx of Ca2+ through presynaptic TRP channels. The PS-induced modulation of excitatory transmission onto hilar neurons could have a broad impact on the excitability of hilar neurons and affect the pathophysiological functions mediated by the hippocampus.  相似文献   
997.
The efficacy of low molecular weight heparin (LMWH) with low dose unfractionated heparin (UFH) during percutaneous coronary intervention (PCI) with or without glycoprotein (Gp) IIb/IIIa inhibitor compared to UFH with or without Gp IIb/IIIa inhibitor has not been elucidated. Between October 2005 and July 2007, 2,535 patients with ST elevation acute myocardial infarction (STEMI) undergoing PCI in the Korean Acute Myocardial Infarction Registry (KAMIR) were assigned to either of two groups: a group with Gp IIb/IIIa inhibitor (n=476) or a group without Gp IIb/IIIa inhibitor (n=2,059). These groups were further subdivided according to the use of LMWH with low dose UFH (n=219) or UFH alone (n=257). The primary end points were cardiac death or myocardial infarction during the 30 days after the registration. The primary end point occurred in 4.1% (9/219) of patients managed with LMWH during PCI and Gp IIb/IIIa inhibitor and 10.8% (28/257) of patients managed with UFH and Gp IIb/IIIa inhibitor (odds ratio [OR], 0.290; 95% confidence interval [CI], 0.132-0.634; P=0.006). Thrombolysis In Myocardial Infarction (TIMI) with major bleeding was observed in LMHW and UFH with Gp IIb/IIIa inhibitor (1/219 [0.5%] vs 1/257 [0.4%], P=1.00). For patients with STEMI managed with a primary PCI and Gp IIb/IIIa inhibitor, LMWH is more beneficial than UFH.  相似文献   
998.
Perineuriomas are uncommon benign peripheral nerve sheath tumors that include soft tissue, sclerosing, reticular, and intraneural variants. Soft tissue perineuriomas arise in a wide anatomic distribution and mostly in patients older than 20 years of age. We report an atypical perineurioma in a 7-year-old girl. The tumor, located in the tongue, was uniformly hypercellular. The tumor cells were spindle-shaped with a slender, elongated, bipolar, wavy cytoplasmic process formation and wavy elongated nuclei, and the architecture was composed of predominantly short fascicles with areas exhibiting a vague storiform pattern. Although the tumor cells generally appeared bland, the tumor showed worrisome features including an infiltrative pattern and occasional mitotic figures. Psammoma bodies were observed in the periphery of the tumor. Immunohistochemically, the cells were positive for epithelial membrane antigen, vimentin, claudin-1, and GLUT-1, but negative for S-100 protein, CD34, and type IV collagen. The authors document a case of soft tissue perineurioma with atypical histological features that occurred in the tongue of a child.  相似文献   
999.
Caspase 8 and survivin are known as key molecules of apoptosis in hepatocellular carcinoma (HCC). The purpose of the present study was to investigate the relationship between promoter methylation and expression and apoptotic function of caspase 8 and survivin in HCC. Promoter methylation of the caspase 8 and survivin gene was analyzed in 73 primary HCC using methylation‐specific polymerase chain reaction. The relationship between immunohistochemical expression of gene products and proliferative/apoptotic indices, and clinicopathological parameters was also investigated. Twenty‐five (34%) and 24 (33%) patients had promoter methylation of caspase 8 and survivin gene. Immunohistochemical staining of caspase 8 and survivin was observed in 35 (48%) and 32 (44%). The methylation of caspase 8 and survivin demonstrated a negative correlation with immunohistochemical expression of gene products (P= 0.049 and P= 0.001). Methylation of caspase 8 and positive expression of its gene product was significantly correlated with high apoptotic indices (P= 0.032 and P= 0.026). Nuclear survivin expression was significantly correlated with high proliferative index (P= 0.001). On survival analysis, positive nuclear survivin expression was associated with a poor prognosis in HCC (P= 0.043). In conclusion, epigenetic alteration by promoter methylation of caspase 8 and survivin may constitute an important regulatory mechanism for expression of those genes in HCC.  相似文献   
1000.
Well‐defined sulfonated block copolymers were prepared by direct thermolysis with block copolymers of n‐butyl acrylate (nBA) and neopentyl styrene sulfonated (NSS), which were synthesized by Cu‐based living radical polymerization ( <1.20). A simple thermal process for 10 min at 150 °C completely deprotected the neopentyl groups in the poly(NSS) block segment to give fully sulfonated polystyrene backbone. SAXS profile of the block copolymer with 47 wt.‐% of poly(NSS) showed lamella structure, which appeared more clearly with long ranged order after sulfonation of the block copolymer.

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