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排序方式: 共有1633条查询结果,搜索用时 31 毫秒
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Clinicopathological analysis of papillary thyroid cancer with PIK3CA alterations in a Middle Eastern population 总被引:1,自引:0,他引:1
Abubaker J Jehan Z Bavi P Sultana M Al-Harbi S Ibrahim M Al-Nuaim A Ahmed M Amin T Al-Fehaily M Al-Sanea O Al-Dayel F Uddin S Al-Kuraya KS 《The Journal of clinical endocrinology and metabolism》2008,93(2):611-618
CONTEXT: Genetic aberration in phosphatidylinositol 3-kinase (PI3K)/AKT pathway has been detected in numerous and diverse human cancers. PIK3CA, which encodes for the catalytic subunit of p110alpha of PI3K, is amplified in some cases of papillary thyroid cancer (PTC). Mutations in the PIK3CA have also been identified in thyroid cancers and, although relatively common in anaplastic thyroid carcinoma, are uncommon in PTC. OBJECTIVE: The objective of the study was to investigate genetic alterations like PIK3CA gene mutation, PIK3CA amplification, RAS, and RAF mutations and to further explore the relationship of these genetic alterations with various clinicopathological characteristics in Middle Eastern PTC. DESIGN: We used the fluorescence in situ hybridization technique for analysis of PIK3CA amplification from 536 PTC cases, and selected amplified samples were further validated by real-time quantitative PCR. Mutation analysis was done by direct DNA sequencing of PIK3CA, N2-RAS, and BRAF genes. RESULTS: PIK3CA amplification was seen in 265 of 499 PTC cases analyzed (53.1%); PIK3CA gene mutations in four of 207 PTC (1.9%); N2-RAS mutations in 16 of 265 PTC (6%); and BRAF mutations in 153 of 296 PTC (51.7%). N-RAS mutations were-associated with an early stage (P = 0.0465) and lower incidence of extrathyroidal extension (P = 0.027), whereas BRAF mutations were-associated with metastasis (P = 0.0274) and poor disease-free survival (P = 0.0121) in PTCs. CONCLUSION: A higher incidence of PIK3CA alterations and the possible synergistic effect of PIK3CA alterations and BRAF mutations suggest their major role in Middle Eastern PTC tumorigenesis and argue for therapeutic targeting of PI3K/AKT and MAPK pathways. 相似文献
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This study reports on the selective separation of scandium (Sc) from other rare earth metals (REMs) using a polymer inclusion membrane (PIM). The PIM prepared with PC-88A (2-ethylhexyl hydrogen-2-ethylhexylphosphonate) alone as the carrier showed high extractability but the poor back-extraction of the extracted Sc3+ ions did not allow the transport of these ions to the receiving solution of a membrane transport system. To overcome this problem, a novel approach was introduced using a mixture of carriers that allowed Sc3+ transport into the receiving solution. A cellulose triacetate (CTA) based PIM containing both PC-88A and Versatic 10 (decanoic acid) as carriers and dioctyl phthalate (DOP) as a plasticizer was prepared for the selective separation of Sc3+ from other REM ions in nitrate media. The membrane composition was optimized and the effect of operational parameters such as pH of the feed solution and composition of the receiving solution was explored. The flux at the membrane/feed solution interface was found to depend significantly on the carrier concentration in the PIM, pH of the feed solution and the receiving solution acidity. The newly developed PIM allowed quantitative and selective transport of Sc3+ thus demonstrating its suitability for the selective recovery of this metal.This study reports on the selective separation of scandium (Sc) from other rare earth metals (REMs) using a polymer inclusion membrane (PIM). 相似文献
25.
Munira Borhany Naveena Fatima Madiha Abid Tahir Shamsi Maha Othman 《Transfusion and apheresis science》2018,57(4):556-560
Background
Hemophilia is an inherited bleeding disorder. With proper treatment and self-care, persons with hemophilia can maintain an active, productive lifestyle. Hemophilia can be mild, moderate, or severe, depending on the degree of plasma clotting factor deficiency. The aim of the study was to assess the utility of ISTH-BAT in diagnosis, determining severity of the bleeding condition in newly diagnosed and known hemophilia patients, compare the bleeding score (BS) in adult and pediatric groups and investigate its association with plasma factor levels.Methods
ISTH-BAT was used to assess BS in a total of 115 patients, 78 with hemophilia A, and 37 with hemophilia B and in 100 controls.Results
BS was significantly higher in HA and HB patients as compared to controls, with no significant difference between HA and HB. The BS was very similar in newly diagnosed compared to known hemophilia patients, lower in pediatric compared to adult and higher in severe compared to mild HA patients.Conclusion
The ISTH BAT can help identify hemophilia patients. Therefore it is a useful tool to distinguish between affected and unaffected individuals with bleeding. Moreover, an important finding of our study is that there is no major difference between the scores in known and newly diagnosed patients. 相似文献26.
Maha Abdalla Harika Sabbineni Roshini Prakash Adviye Ergul Susan C Fagan Payaningal R Somanath 《British journal of pharmacology》2015,172(16):4173-4188
Background and Purpose
Interstitial lung disease accounts for a group of chronic and progressive disorders associated with severe pulmonary vascular remodelling, peripheral vascular rarefaction and fibrosis, thus limiting lung function. We have previously shown that Akt is necessary for myofibroblast differentiation, a critical event in organ fibrosis. However, the contributory role of the Akt-mTOR pathway in interstitial lung disease and the therapeutic benefits of targeting Akt and mTOR remain unclear.Experimental Approach
We investigated the role of the Akt-mTOR pathway and its downstream molecular mechanisms in chronic hypoxia- and TGFβ-induced pulmonary vascular pruning and fibrosis in mice. We also determined the therapeutic benefits of the Akt inhibitor triciribine and the mTOR inhibitor rapamycin for the treatment of pulmonary fibrosis in mice.Key Results
Akt1−/− mice were protected from chronic hypoxia-induced peripheral vascular pruning. In contrast, hyperactivation of Akt1 induced focal fibrosis similar to TGFβ-induced fibrosis. Pharmacological inhibition of Akt, but not the Akt substrate mTOR, inhibited hypoxia- and TGFβ-induced pulmonary vascular rarefaction and fibrosis. Mechanistically, we found that Akt1 modulates pulmonary remodelling via regulation of thrombospondin1 (TSP1) expression. Hypoxic Akt1−/− mice lungs expressed less TSP1. Moreover, TSP1−/− mice were resistant to adMyrAkt1-induced pulmonary fibrosis.Conclusions and Implications
Our study identified Akt1 as a novel target for the treatment of interstitial lung disease and provides preclinical data on the potential benefits of the Akt inhibitor triciribine for the treatment of interstitial lung disease. 相似文献27.
El Halabi Jessica Palmer Nathan Fox Kathe Kohane Isaac Farhat Maha R. 《Journal of gastroenterology》2022,57(1):10-18
Journal of Gastroenterology - Clostridioides difficile infection (CDI) may be rising in severity in the US over the past decade and its treatment landscape is changing given the recent adoption of... 相似文献
28.
Hassan Waleed A. Medhat Basma M. Youssef Maha M. Farag Yomna Mostafa Noha Alnaggar Alshaimaa R. Behiry Mervat E. Abdel Noor Rasha A. Allam Riham S. H. M 《Clinical rheumatology》2021,40(4):1599-1610
Clinical Rheumatology - To investigate the characteristics, evolution, and visual outcome of non-infectious uveitis. Records of 201 patients with non-infectious uveitis (136 (67.7%) males and 84... 相似文献
29.
Miedany Yasser El Gaafary Maha El Toth Mathias Hegazi Mohamed Osama Aroussy Nadia El Hassan Waleed Almedany Samah Nasr Annie Bahlas Sami Galal Salwa 《Clinical rheumatology》2021,40(10):4225-4232
Clinical Rheumatology - The prevalence of sarcopenia with osteoporosis results in a higher risk of falling and fractures. It was noted that patients who had completed their planned 5-year denosumab... 相似文献
30.
Folayan Morenike Oluwatoyin Ibigbami Olanrewaju Brown Brandon El Tantawi Maha Uzochukwu Benjamin Ezechi Oliver C. Aly Nourhan M. Abeldaño Giuliana Florencia Ara Eshrat Ayanore Martin Amogre Ayoola Oluwagbemiga O. Osamika Bamidele Emmanuel Ellakany Passent Gaffar Balgis Idigbe Ifeoma Ishabiyi Anthonia Omotola Jafer Mohammed Khan Abeedha Tu-Allah Khalid Zumama Lawal Folake Barakat Lusher Joanne Nzimande Ntombifuthi P. Popoola Bamidele Olubukola Quadri Mir Faeq Ali Rashwan Maher Roque Mark Shamala Anas Al-Tammemi Ala’a B. Yousaf Muhammad Abrar Abeldaño Zuñiga Roberto Ariel Okeibunor Joseph Chukwudi Nguyen Annie Lu 《AIDS and behavior》2022,26(3):739-751
AIDS and Behavior - The aim of the study was to assess if there were significant differences in the adoption of COVID-19 risk preventive behaviors and experience of food insecurity by people living... 相似文献