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The goal of this study was to develop a long-term active antimicrobial coating for surgical sutures. To this end, two water-insoluble polymeric nanocontainers based on hyperbranched polylysine (HPL), hydrophobically modified by either using glycidyl hexadecyl ether, or a mixture of stearoyl/palmitoyl chloride, were synthesized. Highly stabilized silver nanoparticles (AgNPs, 2–5?nm in size) were generated by dissolving silver nitrate in the modified HPL solutions in toluene followed by reduction with L-ascorbic acid. Poly(glycolic acid)-based surgical sutures were dip-coated with the two different polymeric silver nanocomposites. The coated sutures showed high efficacies of more than 99.5% reduction of adhesion of living Staphylococcus aureus cells onto the surface compared to the uncoated specimen. Silver release experiments were performed on the HPL-AgNP modified sutures by washing them in phosphate buffered saline for a period of 30?days. These coatings showed a constant release of silver ions over more than 30?days. After this period of washing, the sutures retained their high efficacies against bacterial adhesion. Cytotoxicity tests using L929 mouse fibroblast cells showed that the materials are basically non-cytotoxic.  相似文献   
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This study tested whether combined therapy with melatonin and apoptotic adipose‐derived mesenchymal stem cells (A‐ADMSCs) offered additional benefit in ameliorating sepsis‐induced acute kidney injury. Adult male Sprague–Dawley rats (n = 65) were randomized equally into five groups: Sham controls (SC), sepsis induced by cecal‐ligation and puncture (CLP), CLP‐melatonin, CLP‐A‐ADMSC, and CLP‐melatonin‐A‐ADMSC. Circulating TNF‐α level at post‐CLP 6 hr was highest in CLP and lowest in SC groups, higher in CLP‐melatonin than in CLP‐A‐ADMSC and CLP‐melatonin‐A‐ADMSC groups (all P < 0.001). Immune reactivity as reflected in the number of splenic helper‐, cytoxic‐, and regulatory‐T cells at post‐CLP 72 hr exhibited the same pattern as that of circulating TNF‐α among all groups (P < 0.001). The histological scoring of kidney injury and the number of F4/80+ and CD14+ cells in kidney were highest in CLP and lowest in SC groups, higher in CLP‐melatonin than in CLP‐A‐ADMSC and CLP‐melatonin‐A‐ADMSC groups, and higher in CLP‐A‐ADMSC than in CLP‐melatonin‐A‐ADMSC groups (all P < 0.001). Changes in protein expressions of inflammatory (RANTES, TNF‐1α, NF‐κB, MMP‐9, MIP‐1, IL‐1β), apoptotic (cleaved caspase 3 and PARP, mitochondrial Bax), fibrotic (Smad3, TGF‐β) markers, reactive‐oxygen‐species (NOX‐1, NOX‐2), and oxidative stress displayed a pattern identical to that of kidney injury score among the five groups (all P < 0.001). Expressions of antioxidants (GR+, GPx+, HO‐1, NQO‐1+) were lowest in SC group and highest in CLP‐melatonin‐A‐ADMSC group, lower in CLP than in CLP‐melatonin and CLP‐A‐ADMSC groups, and lower in CLP‐melatonin‐ than in CLP‐A‐ADMSC‐tretaed animals (all P < 0.001). In conclusion, combined treatment with melatonin and A‐ADMSC was superior to A‐ADMSC alone in protecting the kidneys from sepsis‐induced injury.  相似文献   
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Background: The sanction that an athlete receives when an anti-doping rule violation has been committed depends on the specific circumstances of the case. Anti-doping tribunals decide on the final sanction, following the rules of the World Anti-Doping Code. Objectives: To assess the athletes’ degree of fault based on the length of sanctions imposed on them to feed policy-related discussions. Methods: Analysing data from the results management database of the World Anti-Doping Agency for anonymous information of anti-doping rule violations in eight selected sports covering the years 2010-2012. Results: Four out of ten athletes who committed an anti-doping rule violation received a suspension that was lower than the standard. This is an indication that tribunals in many instances are not convinced that the athletes concerned were completely at fault, that mitigating circumstances were applicable, or that full responsibility of the suspected violation should not be held against them. Anabolic agents, peptide hormones, and hormone modulators lead to higher sanctions, as do combinations of several anti-doping rule violations. Conclusions: This first analysis of information from the World Anti-Doping Agency's results management database indicates that a large proportion of the athletes who commit anti-doping rule violations may have done this unintentionally. Anti-doping professionals should strive to improve this situation in various ways.  相似文献   
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Macao, a special administrative region (SAR) of the People’s Republic of China, is located in southern China and shares the border with mainland China. It is the most densely populated region in the world, with a population of 667400 and a total land area of 32.9 square kilometers in 2019. Since the first case diagnosed on January 22, 2020, there was a total of 45 laboratory-confirmed coronavirus disease 2019 (COVID-19) cases in Macao, of which 43 patients (96%) were imported cases. To date, all patients had been discharged successfully from Centro Hospitalar Conde de São Januário, a designated hospital to manage all COVID-19 patients in Macao. Eventually, no patient died, and no local community outbreak was noted. This opinion review describes the underlying factors that could have contributed to the successful experience in Macao SAR, China, which include the following: (1) Early implementation of containment measures; (2) Large-scale quarantine using hotel rooms to reduce the risk of a local outbreak; and (3) Multidisciplinary co-operation and transparency of information to the public. Although the successful experience in Macao SAR, China, may not be generalized to other regions, it should not be unreasonable to be well prepared with sufficient logistic support to conduct timely containment and early detection of episodic cases to prevent the backsliding of COVID-19 outbreak.  相似文献   
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International Journal of Clinical Pharmacy - Background Drug-related problems are relatively common among hospitalised patients and may be detrimental to patients and even increase healthcare...  相似文献   
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