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941.
Kyu Yun Jang Yo Na Kim Jun Sang Bae Myoung Ja Chung Woo Sung Moon Myoung Jae Kang Dong Geun Lee Ho Sung Park 《Translational oncology》2012,5(5):370-378
Background
The aim of this study is to investigate the prevalence and prognostic impact of β-catenin and cyclin D1 expression in colorectal carcinoma (CRC) patients.Method
We evaluated immunohistochemial expression of β-catenin and cyclin D1 using 2-mm cores from 220 CRC patients for tissue microarray, and its significance was statistically evaluated.Result
Positive expression of β-catenin and cyclin D1 was found in 72.5% (158 of 218 cases) and 59.4% (129 of 217 cases) of CRC patients, respectively. Expression of β-catenin was significantly correlated with tumor location (P = .017), differentiation (P = .010), lymph node metastasis (P = .032), preoperative carcinoembryonic antigen level (P = .032), and cyclin D1 expression (P = .005). Expression of cyclin D1 was significantly correlated with recurrence and/or metastasis (P = .004). In univariate analysis, β-catenin expression predicted more favorable overall survival (P = .022) and cyclin D1 expression predicted both more favorable overall survival and relapse-free survival (P = .004 and P = .006, respectively). Multivariate analysis showed that tumor stage and expression of cyclin D1 were independent prognostic factors significantly associated with overall survival and relapse-free survival.Conclusion
This study shows that expression of β-catenin and cyclin D1 is associated with favorable clinicopathologic variables and it is a clinically significant prognostic indicator for CRC patients. 相似文献942.
FOXP3 is an X-linked breast cancer suppressor gene and an important repressor of the HER-2/ErbB2 oncogene 总被引:6,自引:0,他引:6
943.
944.
Soon‐Hwan Kwon Ji‐Eun Bae Sang‐Hyup Lee Sang‐Dae Lee Kwon‐Seok Chae 《Entomological Research》2016,46(4):272-277
Geotaxis and phototaxis are movements in response to gravity and light, respectively, and are commonly observed in nature. The interactions between these two types of movement have been shown to confer ecological advantages to many taxa. Although several studies have been conducted on phototaxis and geotaxis in various organisms, reports on the interactions between positive phototaxis and negative geotaxis are lacking. In the fruit fly, Drosophila melanogaster, any direct interactions that exist between positive phototaxis and negative geotaxis are yet to be determined and the ecological significance of such interactions remains unclear. In the present study, the effects of gravity on positive phototaxis in a Y‐maze were investigated using the Canton‐S wild type and gravity‐sensing‐deficient pyx3 mutant fruit flies. Gravity sensing was not necessary for horizontal positive phototaxis, but was required for vertical positive phototaxis. These results suggest that gravitoreception may selectively modulate positive phototaxis depending on the vertical and horizontal movements of the fruit flies. 相似文献
945.
Sang-Joo Kim Hong-Joon Park Borum Sagong Seung-Hyun Bae Se-Kyung Oh Jeong-In Baek Jae Young Choi Kyu-Yup Lee Un-Kyung Kim 《Genes & genomics.》2016,38(10):961-966
The collagen type XI alpha 2 gene (COL11A2) is associated with autosomal dominant non-syndromic hearing loss (ADNSHL), and all mutations of this gene in ADNSHL are missense mutations. To evaluate its potential as a major causative gene of ADNSHL in the Korean population, we performed genetic analysis of COL11A2 in 75 unrelated Korean patients with ADNSHL. Consequently, 5 non-synonymous variants, 7 synonymous variants, and 6 intronic variants were identified in COL11A2. Among them, a novel variant, p.G829R (c.2485G>C) was found in a patient as a heterozygote. However, pedigree analysis showed this variation was not co-segregated with hearing loss. Previously reported variants p.G230W (c.688G>T) and p.P1422L (c.4265C>T) were discovered in Korean patients. However, these variants were also detected in normal individuals. These results suggest that COL11A2 is not a major causative gene of ADNSHL in the Korean population. 相似文献
946.
Improved Method of Enumeration of Attached Bacteria for Study of Fluctuation in the Abundance of Attached and Free-Living Bacteria in Response to Diel Variation in Seawater Turbidity 总被引:2,自引:2,他引:2 下载免费PDF全文
Sample preparation for enumerating attached bacteria in turbid seawater by epifluorescence microscopy was improved by treating samples with a surfactant (Tween 80) followed by sonication. With optimal treatment with Tween 80 (final concentration, 10 ppm [10 μg/ml]) and sonication, as many as 10 times more attached bacteria were enumerated from turbid seawater relative to the number enumerated from an untreated control. Dispersion of bacteria by sonication alone resulted in the enumeration of only 42 to 72% of the attached bacteria. By this technique, fluctuations in the number of attached and free-living bacteria were determined in water from Aransas Pass, Tex., where surface sediments are resuspended on a regular basis by tidal currents. The abundance of attached bacteria increased in proportion to the seawater turbidity that resulted from sediment resuspension. The variation in abundance of free-living bacteria was not directly related to seawater turbidity. However, the magnitude of fluctuation in the abundance of free-living bacteria was related to the extent of turbidity variation during diurnal tides. 相似文献
947.
It has been reported that oxytocin is produced not only in the hypothalamus and posterior pituitary but also in outside the classical hypothalamo-neurohypophyseal axis such as the ovary, testis, placenta and in some nonreproductive sites. In the mare, oxytocin-mRNA has been identified in the endometrium, and oxytocin and its neurophysin have been identified in the uterus. In the present study, oxytocin was localised in the endometrium of the mare at the light microscopic and ultrastructural level by immunostaining and immunogold labelling of endometrial biopsy specimens collected during estrus.Strong positive immunostaining for oxytocin was found in the secretory vesicles of the secretory (nonciliated) epithelial cells of the uterine lumen and of the superficial glands. Using immunogold labelling, oxytocin was detected in the secretory vesicles of secretory epithelial cells. The vesicles containing immunoreactive oxytocin were present on the luminal surface suggesting that oxytocin is secreted into the uterine lumen by apical exocytosis. There was no positive immunostaining in ciliated epithelial cells of the uterine lumen and endometrial glands, in the stromal cells, or in the basal endometrial glands. To our knowledge, this is the first report of the location of oxytocin in specific secretory cells in the endometrium of any domestic species. This locally synthesised uterine oxytocin may have an important role in the autocrine/paracrine control of uterine contractility and luteolysis in the mare. 相似文献
948.
Young Eun Kwon Sung Jun Bae Myungjin Kim Jae Hong Seol 《Biochemical and biophysical research communications》2013,430(1):213-217
CHFR ubiquitin ligase acts as a checkpoint upon DNA damage and its functional inactivation is one of key characteristics of tumor development and metastasis. Despite the crucial role in maintaining genome integrity and cell cycle progression, little is known how CHFR stability is regulated. Here, we showed that CHFR is covalently modified by SUMO-1 at lysine 663 and subsequently destabilized by ubiquitin–proteasome system. While CHFRK663R substitution mutation does not alter its subcellular localization, SUMOylation-defective CHFRK663R-stable cells exhibit substantial growth suppression due to the increased stability of CHFRK663R. Moreover, protein level of CHFR, not CHFRK663R, is rapidly declined under SUMOylation-promoting conditions, and SENP2 deSUMOylating enzyme reverses its SUMO-modification. Collectively, we demonstrated that CHFR stability is regulated by SUMOylation-dependent proteasomal degradation. Therefore, our study underscores the importance of CHFR SUMOylation as a new regulatory mechanism of CHFR and highlights the emerging role of SUMOylation in modulating protein stability. 相似文献
949.
Soo-Jin Park Kyoung-Pil Lee Saeromi Kang Hae-Young Chung Yoe-Sik Bae Fumikazu Okajima Dong-Soon Im 《Cellular signalling》2013,25(11):2147-2154
Lysophosphatidylethanolamine (LPE) is a lyso-type metabolite of phosphatidylethanolamine (a plasma membrane component), and its intracellular Ca2 + ([Ca2 +]i) increasing actions may be mediated through G-protein-coupled receptor (GPCR). However, GPCRs for lysophosphatidic acid (LPA), a structurally similar representative lipid mediator, have not been implicated in LPE-mediated activities in SK-OV3 or OVCAR-3 ovarian cancer cells or in receptor over-expression systems. In the present study, LPE-induced [Ca2 +]i increase was observed in MDA-MB-231 cells but not in other breast cancer cell lines. In addition, LPE- and LPA-induced responses showed homologous and heterologous desensitization. Furthermore, VPC32183 and Ki16425 (antagonists of LPA1 and LPA3) inhibited LPE-induced [Ca2 +]i increases, and knockdown of LPA1 by transfection with LPA1 siRNA completely inhibited LPE-induced [Ca2 +]i increases. Furthermore, the involvement of CD97 (an adhesion GPCR) in the action of LPA1 in MDA-MB-231 cells was demonstrated by siRNA transfection. Pertussis toxin (a specific inhibitor of Gi/o proteins), edelfosine (an inhibitor of phospholipase C), or 2-APB (an inhibitor of IP3 receptor) completely inhibited LPE-induced [Ca2 +]i increases, whereas HA130, an inhibitor of autotaxin/lysophospholipase D, did not. Therefore, LPE is supposed to act on LPA1-CD97/Gi/o proteins/phospholipase C/IP3/Ca2 + rise in MDA-MB-231 breast cancer cells. 相似文献
950.