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1.
The effect of hyperoxia on levels of DNA damage and global DNA methylation was examined in lung epithelial-like A549 cells. DNA damage was assessed by the single-cell gel electrophoresis (comet assay) and DNA methylation status by the cytosine extension assays. Cells exposed to ionizing radiation (0, 1, 2, 4, or 8 Gy) showed increasing rates of percentage of DNA in the tail and tail length with increasing radiation dose. When cells were exposed to room air (normoxia) for 1 day and 95% O2 (hyperoxia) for 1, 2, 3, 4, and 5 days, data indicated that hyperoxia caused time-dependent increases in levels of (a) single strand breaks, (b) double strand breaks, and (c) 8-oxoguanine. Decreased DNA methylation also was observed at day 5 of hyperoxic exposure, suggesting that hyperoxia-induced DNA damage can influence patterns of DNA methylation in a lung-derived cell line.  相似文献   
2.
Quality of Life Research - Beauty care (BTC) is offered at many cancer hospitals having a great uptake among patients. Nevertheless, its benefits in the Quality of life (QoL) of cancer survivors...  相似文献   
3.
Ageing is associated with postprandial muscle vascular and metabolic dysfunction, suggesting vascular modifying interventions may be of benefit. Reflecting this, we investigated the impact of acute cocoa flavanol (450–500 mg) intake (versus placebo control) on vascular (via ultrasound) and glucose/insulin metabolic responses (via arterialised/venous blood samples and ELISA) to an oral nutritional supplement (ONS) in twelve healthy older adults (50% male, 72 ± 4 years), in a crossover design study. The cocoa condition displayed significant increases in m. vastus lateralis microvascular blood volume (MBV) in response to feeding at 180 and 240-min after ONS consumption (baseline: 1.00 vs. 180 min: 1.09 ± 0.03, p = 0.05; 240 min: 1.13 ± 0.04, p = 0.002), with MBV at these timepoints significantly higher than in the control condition (p < 0.05). In addition, there was a trend (p = 0.058) for MBV in m. tibialis anterior to increase in response to ONS in the cocoa condition only. Leg blood flow and vascular conductance increased, and vascular resistance decreased in response to ONS (p < 0.05), but these responses were not different between conditions (p > 0.05). Similarly, glucose uptake and insulin increased in response to ONS (p < 0.05) comparably between conditions (p > 0.05). Thus, acute cocoa flavanol supplementation can potentiate oral feeding-induced increases in MBV in older adults, but this improvement does not relay to muscle glucose uptake.  相似文献   
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5.
Over the last six years, the practice of cardiology in the U.S. has experienced a substantial transition from independent practice to practices integrated within hospital systems. This change has been driven by major economic factors that have largely been determined by the federal government. Meanwhile, cardiologists? salaries and the demand for new cardiologists have remained stable. Best practices have embraced this new partnership with hospital systems to improve quality, cost, and access to cardiovascular care.  相似文献   
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Compensatory signaling pathways in tumors confer resistance to targeted therapy, but the pathways and their mechanisms of activation remain largely unknown. We describe a procedure for quantitative proteomics and phosphoproteomics on snap-frozen biopsies of hepatocellular carcinoma (HCC) and matched nontumor liver tissue. We applied this procedure to monitor signaling pathways in serial biopsies taken from an HCC patient before and during treatment with the multikinase inhibitor sorafenib. At diagnosis, the patient had an advanced HCC. At the time of the second biopsy, abdominal imaging revealed progressive disease despite sorafenib treatment. Sorafenib was confirmed to inhibit MAPK signaling in the tumor, as measured by reduced ribosomal protein S6 kinase phosphorylation. Hierarchical clustering and enrichment analysis revealed pathways broadly implicated in tumor progression and resistance, such as epithelial-to-mesenchymal transition and cell adhesion pathways. Thus, we describe a protocol for quantitative analysis of oncogenic pathways in HCC biopsies and obtained first insights into the effect of sorafenib in vivo. This protocol will allow elucidation of mechanisms of resistance and enable precision medicine.Hepatocellular carcinoma (HCC) is a global health concern with an estimated 750,000 new cases per year (1). In more than 80% of cases, HCC arises in a setting of liver cirrhosis mainly of alcoholic or viral origin (2). The prognosis for HCC patients is poor, with less than 30% qualifying for curative treatments such as tumor resection or liver transplantation (2). Median survival time of patients that cannot be treated surgically is less than 1 y. Sorafenib is the only approved targeted therapy for HCC, prolonging median patient survival by ∼3 mo (3). Sorafenib is a multikinase inhibitor of Raf (B and C), vascular endothelial growth factor receptor (VEGFR), and platelet-derived growth factor receptor (PDGFR) (4), which presumably inhibits not only tumor cells but also endothelial cells responsible for tumor vascularization.Resistance to a targeted cancer drug can be intrinsic or adaptive (5). Sorafenib is largely cytostatic (6), suggesting that intrinsic resistance is more common in tumors, although some reports describe tumor shrinkage upon sorafenib treatment (7). Studies involving HCC cell lines or immunohistochemical staining of tumor sections revealed that sorafenib resistance correlates with the up-regulation of several signaling pathways, including the mammalian target of rapamycin (mTOR) pathway as assayed by S6 S235/236 (8) and Akt S473 phosphorylation (9). Other potential resistance mechanisms involve epithelial-to-mesenchymal transition (EMT) and autophagy (10, 11). However, the molecular mechanisms of sorafenib resistance in patients are largely unknown. Understanding the pathways that confer intrinsic or adaptive resistance would allow precision medicine and increase treatment efficacy.Proteomic analysis allows the identification of drug targets for cancer treatment and biomarkers for cancer classification or recurrence. In particular, MS is a powerful tool for resolving the complexity of cancer signaling pathways. With regard to HCC, qualitative proteomics has been performed on resected tumor material (12), laser-capture microdissected material from tissue sections (13, 14), and primary hepatocytes or serum derived from patients (15, 16). These studies (17, 18) identified HCC biomarkers such as glutamine synthetase and heat shock protein 70 (Hsp70) that are currently in use for diagnosis (19, 20). Quantitative proteomics has been performed on HCC resected tissue and serum (21, 22). Recently, proteomics has been performed on tumor biopsies of renal cell carcinoma patients (23). Several studies also have described phosphoproteomic analyses of resected HCC or other cancer material (2426), in some cases quantifying up to 8,000 phosphorylated sites (hereafter referred to as “phosphosites”) starting with 2 mg of protein (18, 2730). However, to our knowledge, quantitative proteomics and phosphoproteomics, hereafter collectively referred to as “(phospho)proteomics,” have yet to be performed on tumor biopsies, possibly because biopsy material is nonrenewable and typically provides only a very small amount of protein. Importantly, quantitative (phospho)proteomics on serial biopsies taken before and during treatment has not been described. We note that although a biopsy procedure generates less material than a resection, it has the important advantage of capturing normally dynamic properties of a tumor, such as the phosphorylation status of signaling pathways. Biopsies are immediately snap-frozen upon removal from the patient and, unlike resected tissue, are obtained without causing ischemia or hypoglycemia in the collected tissue. Needle biopsies are taken routinely to diagnose and stage the disease. Another important consideration is a method to perform quantitative (phospho)proteomics, such as super-SILAC (“SILAC” is an acronym for “stable isotope labeling of amino acids in cell culture”), that allows direct comparison of biopsies obtained at different times or from different patients (31).We describe quantitative (phospho)proteomic analyses of needle biopsies of HCC and matched nontumor tissue from a human patient. These analyses provide a global snapshot of signaling pathways in the biopsy material. Analyzing serial biopsies taken from a patient before and during therapy, we measured differences in signaling pathways between tumor and matched nontumor control tissue and the changes in these signaling pathways upon sorafenib treatment. Our findings provide insight into mechanisms of tumor progression and resistance to cancer therapy.  相似文献   
8.
As an accrediting agency recognized by the U.S. Department of Education (USDE) and the Council for Higher Education Accreditation (CHEA), the Accreditation Commission for Education in Nursing (ACEN) has established Accreditation Standards and Criteria for the evaluation of nursing programs, including the evaluation of outcomes. This article focuses on the essential components and processes for systematic evaluation of program outcomes, including licensure examination pass rate, program completion rate, and job placement rate.  相似文献   
9.
Purpose

Describe CYP2C19 sequencing results in the largest series of clopidogrel-treated cases with stent thrombosis (ST), the closest clinical phenotype to clopidogrel resistance. Evaluate the impact of CYP2C19 genetic variation detected by next-generation sequencing (NGS) with comprehensive annotation and functional studies.

Methods

Seventy ST cases on clopidogrel identified from the PLATO trial (n =?58) and Mayo Clinic biorepository (n =?12) were matched 1:1 with controls for age, race, sex, diabetes mellitus, presentation, and stent type. NGS was performed to cover the entire CYP2C19 gene. Assessment of exonic variants involved measuring in vitro protein expression levels. Intronic variants were evaluated for potential splicing motif variations.

Results

Poor metabolizers (n =?4) and rare CYP2C19*8, CYP2C19*15, and CYP2C19*11 alleles were identified only in ST cases. CYP2C19*17 heterozygote carriers were observed more frequently in cases (n =?29) than controls (n =?18). Functional studies of CYP2C19 exonic variants (n =?11) revealed 3 cases and only 1 control carrying a deleterious variant as determined by in vitro protein expression studies. Greater intronic variation unique to ST cases (n =?169) compared with controls (n =?84) was observed with predictions revealing 13 allele candidates that may lead to a potential disruption of splicing and a loss-of-function effect of CYP2C19 in ST cases.

Conclusion

NGS detected CYP2C19 poor metabolizers and paradoxically greater number of so-called rapid metabolizers in ST cases. Rare deleterious exonic variation occurs in 4%, and potentially disruptive intronic alleles occur in 16% of ST cases. Additional studies are required to evaluate the role of these variants in platelet aggregation and clopidogrel metabolism.

  相似文献   
10.
The transmissible spongiform encephalopathy (TSE) diseases are rare, neurodegenerative diseases that include scrapie in sheep, bovine spongiform encephalopathy, and Creutzfeldt-Jakob disease in humans. There are no effective treatments available for clinical use in humans. We now demonstrate that, in 2 different rodent models of scrapie, multiple pretreatments with the cyclic tetrapyrrole phthalocyanine tetrasulfonate (PcTS) were as effective at delaying disease as multiple treatments starting at the time of infection. At low doses of scrapie infectivity, PcTS also protected some mice from peripheral scrapie infection, even if treatment was initiated several weeks after infection. Furthermore, PcTS completely inactivated low levels of scrapie infectivity when incubated with the infectious inoculum. Thus, PcTS has a broad range of antiscrapie activities. These findings suggest that cyclic tetrapyrroles may be useful both prophylactically and therapeutically against TSE diseases in vivo, as well as for inactivation of TSE infectivity suspended in solution.  相似文献   
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