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991.
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Graphene supports in vitro proliferation and osteogenic differentiation of goat adult mesenchymal stem cells: potential for bone tissue engineering
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Hoda Elkhenany Lisa Amelse Andersen Lafont Shawn Bourdo Marc Caldwell Nancy Neilsen Enkeleda Dervishi Oshin Derek Alexandru S. Biris David Anderson Madhu Dhar 《Journal of applied toxicology : JAT》2015,35(4):367-374
Current treatments for bone loss injuries involve autologous and allogenic bone grafts, metal alloys and ceramics. Although these therapies have proved useful, they suffer from inherent challenges, and hence, an adequate bone replacement therapy has not yet been found. We hypothesize that graphene may be a useful nanoscaffold for mesenchymal stem cells and will promote proliferation and differentiation into bone progenitor cells. In this study, we evaluate graphene, a biocompatible inert nanomaterial, for its effect on in vitro growth and differentiation of goat adult mesenchymal stem cells. Cell proliferation and differentiation are compared between polystyrene‐coated tissue culture plates and graphene‐coated plates. Graphitic materials are cytocompatible and support cell adhesion and proliferation. Importantly, cells seeded on to oxidized graphene films undergo osteogenic differentiation in fetal bovine serum‐containing medium without the addition of any glucocorticoid or specific growth factors. These findings support graphene's potential to act as an osteoinducer and a vehicle to deliver mesenchymal stem cells, and suggest that the combination of graphene and goat mesenchymal stem cells provides a promising construct for bone tissue engineering. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
994.
The Meth Project and Teen Meth Use: New Estimates from the National and State Youth Risk Behavior Surveys
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In this note, we use data from the national and state Youth Risk Behavior Surveys for the period 1999 through 2011 to estimate the relationship between the Meth Project, an anti‐methamphetamine advertising campaign, and meth use among high school students. During this period, a total of eight states adopted anti‐meth advertising campaigns. After accounting for pre‐existing downward trends in meth use, we find little evidence that the campaign curbed meth use in the full sample. We do find, however, some evidence that the Meth Project may have decreased meth use among White high school students. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Background: Synthetic cannabinoids (SCs) are a class of drugs of abuse with deleterious consequences. Despite governmental regulations related to distribution and sale, SC variants are still available online. More research is needed to determine SC use prevalence and factors associated with SC use, especially among young adults. Methods: One thousand eighty individuals, 18–25 years old, were surveyed, between January 2012 and July 2013, during recruitment for a randomized controlled trial investigating health behaviors in young adults. Advertisements were placed online and in community locations seeking individuals “who had recently used marijuana or alcohol.” Respondents were queried about their use of alcohol and drugs, including SCs, in the last month. Results: Participants averaged 21.4 years old and were 53.4% male. Nearly 59% were non-Hispanic white, 15% were African American, 15% were Hispanic, and 11% identified as other. Approximately 9% reported SC use in the last month, a level higher than the reported use of opioids, cocaine, or hallucinogens. SC use was significantly associated with male gender, not being enrolled in school, and with use of cigarettes, binge alcohol drinking, daily and weekly marijuana use, and other drugs of abuse. There was a significant decrease in SC use after the federal ban in July 2012. Conclusions: SC use was common in the past month and often overlaps with other drug use, particularly marijuana use, and should be asked about during clinical encounters with young adults. 相似文献
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Anderson Kelley M. Ferranti Erin P. Alagha Emily Couvillon Mykityshyn Emma French Casey E. Reilly Carolyn Miller 《Heart failure reviews》2022,27(6):2223-2249
Heart Failure Reviews - There is an expanding body of research on the bidirectional relationship of the human gut microbiome and cardiovascular disease, including heart failure (HF). Researchers... 相似文献
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Chaitanya Joshi Ranjeet Bapat William Anderson Dana Dawson Karolin Hijazi George Cherukara 《Trends in Cardiovascular Medicine》2021,31(1):69-82
BackgroundMicrobial translocation from inflamed periodontal pockets into coronary atheroma via systemic circulation is one of the proposed pathways that links periodontitis and myocardial infarction (MI). The purpose of this systematic review is to determine the reported prevalence of periodontal microorganisms in coronary atheroma and/or aspirated clot samples collected from MI patients with periodontal disease.MethodologyThe “Preferred Reporting Items for Systematic Reviews and Meta-Analyses” (PRISMA) guidelines were followed. Six databases were systematically searched using Medical Subject Headings/Index and Entree terms. After a thorough screening, fourteen publications spanning over ten years (2007–2017) were eligible for this systematic review and meta-analysis.ResultsOut of 14 included studies, 12 reported presence of periodontal bacterial DNA in coronary atherosclerotic plaque specimens. Overall, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans were the most frequently detected periodontal bacterial species. Meta-analysis revealed that the prevalence of P. gingivalis was significantly higher than A. actinomycetemcomitans in coronary atheromatous plaque samples. Apart from periodontal microbes, DNA from a variety of other microbes e.g. Pseudomonas fluorescens, Streptococcus species, Chlamydia pneumoniae were also recovered from the collected samples.ConclusionConsistent detection of periodontal bacterial DNA in coronary atheroma suggests their systemic dissemination from periodontal sites. It should further be investigated whether they are merely bystanders or induce any structural changes within coronary arterial walls. 相似文献