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When living organisms become sick as a result of a bacterial infection, a suite of brain-mediated responses occur, including fever, anorexia and sleepiness. Systemic administration of lipopolysaccharide (LPS), a common constituent of bacterial cell walls, increases body temperature and non-rapid eye movement (NREM) sleep in animals and induces the production of pro-inflammatory prostaglandins (PGs). PGE2 is the principal mediator of fever, and both PGE2 and PGD2 regulate sleep–wake behavior. The extent to which PGE2 and PGD2 are involved in the effect of LPS on NREM sleep remains to be clarified. Therefore, we examined LPS-induced changes in body temperature and NREM sleep in mice with nervous system-specific knockouts (KO) for the PGE2 receptors type EP3 or EP4, in mice with total body KO of microsomal PGE synthase-1 or the PGD2 receptor type DP, and in mice treated with the cyclooxygenase (COX) inhibitor meloxicam. We observed that LPS-induced NREM sleep was slightly attenuated in mice lacking EP4 receptors in the nervous system, but was not affected in any of the other KO mice or in mice pretreated with the COX inhibitor. These results suggest that the effect of LPS on NREM sleep is partially dependent on PGs and is likely mediated mainly by other pro-inflammatory substances. In addition, our data show that the main effect of LPS on body temperature is hypothermia in the absence of nervous system EP3 receptors or in the presence of a COX inhibitor. 相似文献
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Adeline Tarantini Sylvie Huet Gérard Jarry Rachelle Lanceleur Martine Poul Ana Tavares Nádia Vital Henriqueta Louro Maria João Silva Valérie Fessard 《Environmental and molecular mutagenesis》2015,56(2):218-227
Synthetic amorphous silica (SAS) in its nanosized form is now used in food applications although the potential risks for human health have not been evaluated. In this study, genotoxicity and oxidative DNA damage of two pyrogenic (NM‐202 and 203) and two precipitated (NM‐200 and ‐201) nanosized SAS were investigated in vivo in rats following oral exposure. Male Sprague Dawley rats were exposed to 5, 10, or 20 mg/kg b.w./day for three days by gavage. DNA strand breaks and oxidative DNA damage were investigated in seven tissues (blood, bone marrow from femur, liver, spleen, kidney, duodenum, and colon) with the alkaline and the (Fpg)‐modified comet assays, respectively. Concomitantly, chromosomal damage was investigated in bone marrow and in colon with the micronucleus assay. Additionally, malondialdehyde (MDA), a lipid peroxidation marker, was measured in plasma. When required, a histopathological examination was also conducted. The results showed neither obvious DNA strand breaks nor oxidative damage with the comet assay, irrespective of the dose and the organ investigated. Similarly, no increases in chromosome damage in bone marrow or lipid peroxidation in plasma were detected. However, although the response was not dose‐dependent, a weak increase in the percentage of micronucleated cells was observed in the colon of rats treated with the two pyrogenic SAS at the lowest dose (5 mg/kg b.w./day). Additional data are required to confirm this result, considering in particular, the role of agglomeration/aggregation of SAS NMs in their uptake by intestinal cells. Environ. Mol. Mutagen. 56:218–227, 2015. © 2014 Wiley Periodicals, Inc. 相似文献
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Is it possible to make a diagnosis of raw,heated, and baked egg allergy in children using cutoffs? A systematic review 下载免费PDF全文
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目的探讨工作坊模式在护生压疮护理带教中的应用效果,为临床护理带教提供参考。方法选取2018年7月—2019年6月在医院实习的120名护生作为研究对象,随机分为对照组和观察组,各60名护生。对照组采用传统带教法进行压疮培训,观察组采用工作坊教学模式进行培训。培训结束后比较两组护生压疮知识的掌握程度即理论考核、技能操作成绩,教学效果满意度。结果观察组护生对压疮知识的掌握程度即理论考核成绩、技能操作考核成绩远远高于对照组,两组差异具有统计学意义(P<0.05)。95%的观察组护生对工作坊教学模式的效果表示满意,认为工作坊教学模式能够提高学习的兴趣、主动性和临床实践能力,对临床工作有很大帮助。结论工作坊教学模式应用于压疮护理的临床带教,能让护生亲身体验压疮护理的过程,并参与其中,将理论与实践相结合,更好地活跃课堂气氛,启发护生思考,提高护生对压疮理论和技能的掌握,为临床实际工作中压疮护理质量的提高奠定基础。 相似文献
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John Lennon Silva Cunha Amanda Almeida Leite Thamiris de Castro Abrantes Lorena Passoni Vervloet Thayn Melo de Lima Morais Gerson de Oliveira Paiva Neto Tatiana Nayara Librio Kimura Snia Maria Soares Ferreira Ricardo Luiz Cavalcanti de Albuquerque‐Júnior Aline Corrêa Abraho Mario Jos Romaach Bruno Augusto Benevenuto de Andrade Oslei Paes de Almeida Ciro Dantas Soares 《Journal of cutaneous pathology》2021,48(1):24-33
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