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Journal of Materials Science: Materials in Electronics - In this work, the very rapid one-step mechanochemical synthesis of nanocrystalline ternary chalcogenide chalcostibite CuSbS2 prepared from...  相似文献   
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The association between obesity, cancer and cardiovascular disease (CVD) has been demonstrated in animal and epidemiological studies. However, the specific role of visceral obesity on cancer and CVD remains unclear. Visceral adipose tissue (VAT) is a complex and metabolically active tissue, that can produce different adipokines and hormones, responsible for endocrine-metabolic comorbidities. This review explores the potential mechanisms related to VAT that may also be involved in cancer and CVD. In addition, we discuss the shared pharmacological treatments which may reduce the risk of both diseases. This review highlights that chronic inflammation, molecular aspects, metabolic syndrome, secretion of hormones and adiponectin associated to VAT may have synergistic effects and should be further studied in relation to cancer and CVD. Reductions in abdominal and visceral adiposity improve insulin sensitivity, lipid profile and cytokines, which consequently reduce the risk of CVD and some cancers. Several medications have shown to reduce visceral and/or subcutaneous fat. Further research is needed to investigate the pathophysiological mechanisms by which visceral obesity may cause both cancer and CVD. The role of visceral fat in cancer and CVD is an important area to advance. Public health policies to increase public awareness about VAT’s role and ways to manage or prevent it are needed.  相似文献   
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Infections from antibiotic-resistant Staphylococcus aureus and Pseudomonas aeruginosa are a serious threat because reduced antibiotic efficacy complicates treatment decisions and prolongs the disease state in many patients. To expand the arsenal of treatments against antimicrobial-resistant (AMR) pathogens, 600-Da branched polyethylenimine (BPEI) can overcome antibiotic resistance mechanisms and potentiate β-lactam antibiotics against Gram-positive bacteria. BPEI binds cell-wall teichoic acids and disables resistance factors from penicillin binding proteins PBP2a and PBP4. This study describes a new mechanism of action for BPEI potentiation of antibiotics generally regarded as agents effective against Gram-positive pathogens but not Gram-negative bacteria. 600-Da BPEI is able to reduce the barriers to drug influx and facilitate the uptake of a non-β-lactam co-drug, erythromycin, which targets the intracellular machinery. Also, BPEI can suppress production of the cytokine interleukin IL-8 by human epithelial keratinocytes. This enables BPEI to function as a broad-spectrum antibiotic potentiator, and expands the opportunities to improve drug design, antibiotic development, and therapeutic approaches against pathogenic bacteria, especially for wound care.  相似文献   
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The influence of ultrasound power (1000–3000 W/L), citric acid concentration (0–3%) and solid:liquid ratio (1:5–1:15) on the phenolic compounds recovery and antioxidant capacity of Syrah grape skin extracts were evaluated. Total phenolic compounds varied from 6485 to 11732 mg gallic acid/100 g and monomeric anthocyanin content from 453 to 685 mg malvidin-3-glucoside/100 g. The antioxidant capacity measured by ORAC and ABTS methods ranged from 230 to 516 μmol Trolox/g and from 442 to 939 μmol Trolox/g, respectively. The most suitable conditions chosen for extraction, within the studied ranges, were 3000 W/L of power, 2.5% citric acid and solid:liquid ratio of 1:15. The extraction yield was satisfactory, with a recovery of 59% of the quantified phenolic compounds, with only 3 min of processing. Ultrasound was considered a suitable method as compared to the conventional extraction, improving the extraction of phenolic acids and facilitating their release.  相似文献   
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Virtual Reality - The interaction time of students who did spatial ability tests in a virtual reality environment is analyzed. The spatial ability test completion times of 240 and 61 students were...  相似文献   
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The design and synthesis of heparin mimetics with high anticancer activity but no anticoagulant activity is an important task in medicinal chemistry. Herein, we present the efficient synthesis of five Glc-GlcA-Glc-sequenced and one Glc-IdoA-Glc-sequenced non-glycosaminoglycan, heparin-related trisaccharides with various sulfation/sulfonylation and methylation patterns. The cell growth inhibitory effects of the compounds were tested against four cancerous human cell lines and two non-cancerous cell lines. Two d -glucuronate-containing tetra-O-sulfated, partially methylated trisaccharides displayed remarkable and selective inhibitory effects on the growth of ovary carcinoma (A2780) and melanoma (WM35) cells. Methyl substituents on the glucuronide unit proved to be detrimental, whereas acetyl substituents were beneficial to the cytostatic activity of the sulfated derivatives.  相似文献   
10.
Aerosol mass (PM10 and PM2.5) and detailed elemental composition were measured in monthly composites during the calendar year of 2007 at a site in Lahore, Pakistan. Elemental analysis revealed extremely high concentrations of Pb (4.4 μg m− 3), Zn (12 μg m− 3), Cd (0.077 μg m− 3), and several other toxic metals. A significant fraction of the concentration of Pb (84%), Zn (98%), and Cd (90%) was contained in the fine particulate fraction (PM2.5 and smaller); in addition, Zn and Cd were largely (≥ 60%) water soluble. The 2007 annual average PM10 mass concentration was 340 μg m− 3, which is well above the WHO guideline of 20 μg m− 3. Dust sources were found to contribute on average (maximum) 41% (70%) of PM10 mass and 14% (29%) of PM2.5 mass on a monthly basis. Seasonally, concentrations were found to be lowest during the monsoon season (July-September). Principle component analysis identified seven factors, which combined explained 91% of the variance of the measured components of PM10. These factors included three industrial sources, re-suspended soil, mobile sources, and two regional secondary aerosol sources likely from coal and/or biomass burning. The majority of the Pb was found to be associated with one industrial source, along with a number of other toxic metals including As and Cr. Cadmium, another toxic metal, was found at concentrations 16 times higher than the maximum exposure level recommended by the World Health Organization, and was concentrated in one industrial source that was also associated with Zn. These results highlight the importance of focusing control strategies not only on reducing PM mass concentration, but also on the reduction of toxic components of the PM as well, to most effectively protect human health and the environment.  相似文献   
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