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排序方式: 共有344条查询结果,搜索用时 31 毫秒
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Enhanced constitutive invasion activity in human nontumorigenic keratinocytes exposed to a low level of barium for a long time 下载免费PDF全文
Nguyen D. Thang Ichiro Yajima Shoko Ohnuma Nobutaka Ohgami Mayuko Y. Kumasaka Gaku Ichihara Masashi Kato 《Environmental toxicology》2015,30(2):161-167
We have recently demonstrated that exposure to barium for a short time (≤4 days) and at a low level (5 µM = 687 µg/L) promotes invasion of human nontumorigenic HaCaT cells, which have characteristics similar to those of normal keratinocytes, suggesting that exposure to barium for a short time enhances malignant characteristics. Here we examined the effect of exposure to low level of barium for a long time, a condition mimicking the exposure to barium through well water, on malignant characteristics of HaCaT keratinocytes. Constitutive invasion activity, focal adhesion kinase (FAK) protein expression and activity, and matrix metalloproteinase 14 (MMP14) protein expression in primary cultured normal human epidermal keratinocytes, HaCaT keratinocytes, and HSC5 and A431 human squamous cell carcinoma cells were augmented following an increase in malignancy grade of the cells. Constitutive invasion activity, FAK phosphorylation, and MMP14 expression levels of HaCaT keratinocytes after treatment with 5 µM barium for 4 months were significantly higher than those of control untreated HaCaT keratinocytes. Taken together, our results suggest that exposure to a low level of barium for a long time enhances constitutive malignant characteristics of HaCaT keratinocytes via regulatory molecules (FAK and MMP14) for invasion. © 2013 Wiley Periodicals, Inc. Environ Toxicol 30: 161–167, 2015. 相似文献
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Han Thang S. Gulli Giosue Fry Christopher H. Affley Brendan Robin Jonathan Fluck David Kakar Puneet Sharma Pankaj 《Journal of thrombosis and thrombolysis》2022,53(1):218-227
Journal of Thrombosis and Thrombolysis - Complications following thrombolysis for stroke are well documented, and mostly concentrated on haemorrhage. However, the consequences of patients who... 相似文献
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Foley Sarah Hughes Claire Murray Aja Louise Baban Adriana Fernando Asvini D. Madrid Bernadette Osafo Joseph Sikander Siham Abbasi Fahad Walker Susan Van Thang Vo Luong-Thanh Bao-Yen Tomlinson Mark Fearon Pasco Ward Catherine L. Valdebenito Sara Eisner Manuel 《Archives of women's mental health》2021,24(4):627-627
Archives of Women's Mental Health - A Correction to this paper has been published: https://doi.org/10.1007/s00737-021-01122-7 相似文献
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Elongation mechanism and substrate specificity of 2'',5''-oligoadenylate synthetase. 总被引:2,自引:1,他引:2 下载免费PDF全文
J Justesen D Ferbus M N Thang 《Proceedings of the National Academy of Sciences of the United States of America》1980,77(8):4618-4622
2',5'-Oligoadenylate synthetase has been purified from a rabbit reticulocyte lysate to a high degree of purity. The enzyme contained no detectable interfering activities that could degrade the nucleoside triphosphate substrate or the oligomeric products. Two basic properties of this enzyme have been examined: the elongation mechanism for the synthesis of oligoadenylates and the substrate specificity for nucleotides. Kinetic studies on the formation of different oligomeric intermediates show that the dimer pppA2'p5'A is the first product to accumulate in predominant proportion during the first period of reaction; the trimer and other longer oligomers appear after a lag phase. The amount of the trimer increases at the expense of the dimer. Preformed dimers and trimers added to the incubation mixture were readily incorporated into higher oligomers, suggesting the free access of these dimers and trimers to the active center after the onset of polymerization of ATP. The results indicate clearly that the enzyme catalyzes the de novo synthesis of the oligonucleotide from ATP and that the mechanism of elongation of the 2',5'-oligonucleotides catalyzed by the enzyme is not processive. Polymerization of a mixture of ATP and another nucleoside triphosphate shows that the enzyme is not only an ATP polymerase. The 2',5'-oligoadenylate synthetase is in fact a 2',5'-nucleotidyltransferase that catalyzes the formation of co-oligonucleotides. However, the purified reticulocyte enzyme catalyzed only the addition of one unit of GMP, UMP, CMP, 2'-dAMP, 3'-dAMP, dCMP, dGMP, or TMP to the 2'-OH end of a preformed oligoadenylate. A procedure for the separation of 2',5'-oligonucleotides with or without the 5'triphosphate end also is described. 相似文献
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Sebastian S Zeki Rehan Haidry Manuel Justo-Rodriguez Laurence B Lovat Nicholas A Wright Stuart A McDonald 《World journal of gastroenterology : WJG》2014,20(15):4453-4456
Barrett’s oesophagus(BO)is a usually indolent condition that occasionally requires endoscopic therapy.Radiofrequency ablation(RFA)is an effective endoscopic treatment for high grade dysplasia(HGD)and intramucosal cancer in BO.It has a good efficacy,durability and safety profile although complications can occur.Here we describe a case of RFA in a patient with high grade dysplasia.Although the response to treatment was initially very good with the development of neosquamous epithelium,the patient very rapidly developed a squamous cell cancer of the oesophagus confirmed on radiology,histology and immunohistochemistry.Sanger sequencing confirmed that the original HGD and the squamous cell cancer(SCC)were derived from separate clonal origins.The report highlights the fact that SCC of the oesophagus has been noted after endoscopic ablation for BO previously and suggest that ablation of BO may encourage the clonal expansion of cells carrying carcinogenic mutations once a dominant clonal population has been eradicated. 相似文献
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Nguyen Tat Thang Le Thi Hong Nguyen Hoang Thoan Chu Manh Hung Nguyen Van Duy Nguyen Van Hieu Nguyen Duc Hoa 《RSC advances》2020,10(22):12759
Fabrication of a high-performance room-temperature (RT) gas sensor is important for the future integration of sensors into smart, portable and Internet-of-Things (IoT)-based devices. Herein, we developed a NO2 gas sensor based on ultrathin MoS2 nanoflowers with high sensitivity at RT. The MoS2 flower-like nanostructures were synthesised via a simple hydrothermal method with different growth times of 24, 36, 48, and 60 h. The synthesised MoS2 nanoflowers were subsequently characterised by scanning electron microscopy, X-ray diffraction, Raman spectroscopy, energy-dispersive X-ray spectroscopy and transmission electron microscopy. The petal-like nanosheets in pure MoS2 agglomerated to form a flower-like structure with Raman vibrational modes at 378 and 403 cm−1 and crystallisation in the hexagonal phase. The specific surface areas of the MoS2 grown at different times were measured by using the Brunauer–Emmett–Teller method. The largest specific surface area of 56.57 m2 g−1 was obtained for the MoS2 nanoflowers grown for 48 h. This sample also possessed the smallest activation energy of 0.08 eV. The gas-sensing characteristics of sensors based on the synthesised MoS2 nanostructures were investigated using oxidising and reducing gases, such as NO2, SO2, H2, CH4, CO and NH3, at different concentrations and at working temperatures ranging from RT to 150 °C. The sensor based on the MoS2 nanoflowers grown for 48 h showed a high gas response of 67.4% and high selectivity to 10 ppm NO2 at RT. This finding can be ascribed to the synergistic effects of largest specific surface area, smallest crystallite size and lowest activation energy of the MoS2-48 h sample among the samples. The sensors also exhibited a relative humidity-independent sensing characteristic at RT and a low detection limit of 84 ppb, thereby allowing their practical application to portable IoT-based devices.Controlled synthesis of ultrathin MoS2 nanoflowers is crucial to develop a high-performance room-temperature NO2 gas sensor for the future integration of sensors into smart, portable and Internet-of-Things (IoT)-based devices. 相似文献