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41.
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   
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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   
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The impact of decentralisation, socioeconomic changes and healthcare reforms in Indonesia on type and distribution of healthcare providers and quality‐of‐care has been unclear. We examined workforce trends for healthcare facilities from 1993 to 2007 using the Indonesian Family Life Surveys. Each included a sample of public and private healthcare facilities, used standardised interviews for numbers and composition of staffing, and quality‐of‐care vignettes. There was an increase in multiprovider facilities and shift in profile of solo providers—increasing proportions of midwives and drop in doctors in rural areas (including facilities with doctors) and nurses in urban areas. Quality‐of‐care scores were low, particularly for nurses as solo providers. Despite increased numbers of healthcare workers and growth of the private sector, outer Java‐Bali and rural areas continued to be disadvantaged in workforce capacity and quality‐of‐care. The results have implications for accreditation and in‐service training requirements, the legal status of nurses and private sector regulation. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
47.

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   
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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   
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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   
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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   
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