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61.
The main of this study was to evaluate the mutagenic and carcinogenic potential of (+) – usnic acid (UA), using Somatic Mutation and Recombination Test (SMART) and the test for detecting epithelial tumor clones (wts) in Drosophila melanogaster. Larvae from 72 ± 4 h from Drosophila were fed with UA (5.0, 10.0 or 20.0 mM); urethane (10.0 mM) (positive control); and solvent (Milli-Q water, 1% Tween-80 and 3% ethanol) (negative control). ST cross produced increase in total mutant spots in the individuals treated with 5.0, 10.0 or 20.0 mM of UA. HB cross produced spot frequencies in the concentration of 5.0 mM that were higher than the frequency for the same concentration in the ST cross. In the highest concentrations the result was negative, which means that the difference observed can be attributed, in part, to the high levels of P450, suggesting that increasing the metabolic capacity maximized the toxic effect of these doses. In the evaluation of carcinogenesis using the wts test, the results obtained for the same concentrations of UA show a positive result for the presence of tumors when compared to the negative control. We conclude that UA has recombinogenic, mutagenic and carcinogenic effects on somatic cells in D. melanogaster.  相似文献   
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Background

Clear cell renal cell carcinoma (ccRCC) is known to occur across the adult lifetime traversing the spectrum of age-related organismal changes. Little is known as to how the aging process may affect the course of renal cell carcinoma (RCC) and the repertoire of genes involved.

Methods

Using The Cancer Genome Atlas (n?=?436) and Cancer Genomics of the Kidney (n?=?89) datasets, we applied regression analysis to examine associations between patient age and gene expression profiles in ccRCC tumors and normal kidney tissues. Pathway enrichment analysis was performed to identify cellular process that is affected by aging in ccRCC. Moreover, connectivity mapping analysis was used to predict age-dependent response to drug treatments.

Results

Our analysis revealed different age-dependent gene expression spectra in ccRCC and normal kidney tissues. These findings were significant and independently reproducible in both datasets examined. Age up-regulated genes, showing higher expression in older patients, were significantly enriched (false discovery rate <0.05) in normal tissues for pathways associated with immune response and extracellular matrix organization, whereas age up-regulated genes in tumors were enriched for metabolism and oxidation pathways. Strikingly, age down-regulated genes in normal cells were also enriched for metabolism and oxidation, while those in tumors were enriched for extracellular matrix organization. Further in silico analysis of potential drug targets predicted preferential efficacy of Phosphoinositide 3-kinase inhibitor or immunotherapy in association with age.

Conclusion

We report on previously unrecognized associations between age and molecular underpinnings of RCC, including age-associated expression of genes implicated in RCC development or treatment.  相似文献   
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Introduction: Tamoxifen dominates the anti-estrogenic therapy in the early and metastatic breast cancer setting. Tamoxifen has a complex metabolism, being mainly metabolized by CYP2D6 into its 30–100 times more potent metabolite, endoxifen. Recently, a phase I study in which endoxifen as an orally z-endoxifen hydrochloride has been successfully evaluated.

Areas covered: the principal pharmacogenetic and non-genetic differences in the pharmacology of tamoxifen and endoxifen are evaluated. To this end, references from PubMed, Embase or Web of Science, among others, were reviewed As non-genetic factors, important differences and similarities such age, or adherence to tamoxifen therapy are comprehensively illustrated. Additionally, since CYP2D6 genotypes are considered the main limitation of tamoxifen, many studies have investigated the association between the worsened clinical outcomes in patients with non-functional CYP2D6 genotypes. In this review, an overview of the research on this field is presented. Also, a summary describing the literature about individualizing tamoxifen therapy with endoxifen concentrations and its limitations is listed.

Expert opinion: z-endoxifen hydrochloride is only investigated in the metastatic setting, still more research is required before its place in therapeutics is known. Similarly, monitoring tamoxifen efficacy based on endoxifen concentrations might not be overall recommended due to the limited evidence available.  相似文献   

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ObjectivePilates is used increasingly in a variety of clinical settings. However, there is lack of clarity in the literature as to what is meant by the term. Teachers incorporating apparatus based on the designs of Joseph Pilates (1883–1967) into their practice refer to themselves as Comprehensive Teachers, and this group divides itself further into Classical and Contemporary practice. The aim of this research was to explore the meanings of these terms with Comprehensive Teachers and to develop a framework that reflects current views and practice.MethodOnline international survey of Pilates Teachers through closed Facebook forums. Open questions were used to elicit views of the definition and practice of Pilates, and how standards should be set across the sector.ResultsOf 109 participants, 35% were based in the UK and 32% in the USA; 48% identified as Classical teachers, 32% as Contemporary, 5% as both and 15% as Matwork instructors. A thematic analysis of the qualitative data revealed agreement on the scope and content of Classical and Contemporary Comprehensive Pilates, however the discourse indicated there might be stereotyping about each other's practice. Classical teachers, for example, spoke of their own practice as authentic while Contemporary teachers used terms such as strict and inflexible for Classical practice. However, members of either group may incorporate both Classical and Contemporary approaches within their practice. We have designed a Pilates Teaching Framework to take into account the types of apparatus, the types of exercises and the order in which the exercises are executed.ConclusionsA framework that emphasises Pilates teaching rather than teacher practice is proposed for consistency and clarity when describing Pilates in professional and public contexts.  相似文献   
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The inflammatory response induced by cardiopulmonary bypass decreases vascular tone, which in turn can lead to vasoplegic syndrome. Indeed the hypotension consequent to on-pump cardiac surgery often necessitates vasopressor and intravenous fluid support. Methylene blue counteracts vasoplegic syndrome by inhibiting the formation of nitric oxide.We report the use of methylene blue in a 75-year-old man who developed vasoplegic syndrome after cardiac surgery. After the administration of methylene blue, his hypotension improved to the extent that he could be weaned from vasopressors. The use of methylene blue should be considered in patients who develop hypotension refractory to standard treatment after cardiac surgery.  相似文献   
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