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Mehmet Varol Kadriye Benkli Ayşe T. Koparal Rakibe B. Bostancıoğlu 《Drug and chemical toxicology》2019,42(4):436-443
Drug design and discovery studies are important because of the prevalence of diseases without available medical cures. New anticancer agents are particularly urgent because of the high mortality rate associated with cancer. A series of mononuclear gold (III) and platinum (II) complexes based on boronated phenylalanine (BPA) were designed and synthesized using 4,4’-dimethyl-2,2’-dipyridyl (L1) or 1,10-phenanthroline-5,6-dion (L2) ligands to obtain promising anticancer drug candidates. Proton nuclear magnetic resonance, infrared, mass spectrometry, and elemental analyses were utilized for chemical characterizations. Cell viability, cancer cell colony formation, endothelial tube formation, and cytoskeleton staining assays were performed using A549 lung adenocarcinoma and human umbilical vein endothelial cells (HUVECs) to investigate preliminary pharmacological activities. L1-based platinum (II) complex (BPA-L1-Pt) was the most promising complex, and has similar activity with the approved chemotherapy drug cis-platinum. Half maximal inhibitory concentration values for BPA-L1-Pt were 9.15 µM on A549s and 16.61 µM on HUVECs; the values for cis-platinum were 5.24 µM on A549s and 23.14 µM on HUVECs. Consequently, further synthesis studies should be performed to boost the cancer cell selectivity feature of BPA by varying metal and ligand types. 相似文献
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Isabel Ferr‐Eguiluz Gabriela Buccini Amber Hromi‐Fiedler Natalia Rovelo Teresita Gonzlez de Cosío Juan Ricardo Prez‐Escamilla‐Costas Juan Ricardo Prez‐Escamilla‐Gonzlez Rafael Prez‐Escamilla 《Maternal & child nutrition》2020,16(2)
Media can be a powerful communication tool to promote breastfeeding programs, influence mother's breastfeeding behaviour, and generate support among stakeholders for breastfeeding. Yet, there is little information on how media coverage influences a country's breastfeeding enabling environment. This study addressed this gap by conducting a retrospective content analysis of documents published between January 1, 2017 and January 1, 2018 to analyse the media coverage related to breastfeeding in Mexico. Content analysis was based on the breastfeeding gear model and a strategic planning technique to identify strengths, weaknesses, opportunities, and threats for enabling the national breastfeeding environment. Media coverage of breastfeeding was more frequent in August (36% of all documents). The top three topics commonly covered by the media were advocacy events promoting breastfeeding, promotion campaigns, and changes in breastfeeding legislation and policy. In general, the media coverage focused on strengths of specific breastfeeding policies. There was limited news coverage of key factors that negatively influenced or threatened the breastfeeding environment. Findings support the need to design strategies to engage the media covering in more depth and breadth diverse aspects of breastfeeding protection, promotion, and support efforts in Mexico. 相似文献
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Eduardo Rodrigues‐Pinto Joel Ferreira‐Silva Guilherme Macedo Douglas K. Rex 《Digestive endoscopy》2019,31(5):583-587
Cecal intubation is a critical aspect of effective, complete colonoscopy. Difficult colonoscopy is most often considered as one in which it is challenging or impossible to reach the cecum. It may be a common occurrence due to patient and/or endoscopist factors. Incomplete colonoscopies should be avoided, since patients in this context present an important prevalence of lesions that escape examination. The approach to successful cecal intubation should depend on characterization of the problem as redundant colon or difficult sigmoid colon. Most patients with a prior incomplete colonoscopy can be colonoscoped successfully, if careful attention is paid to technique, using a variety of scopes, colonoscopy methods and additional equipment. Sufficient time should be allotted to make the attempt. 相似文献