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Upon infection or brain damage, microglia are activated to play roles in immune responses, including phagocytosis and soluble factor release. However, little is known whether the event of phagocytosis could be a trigger for releasing soluble factors from microglia. In this study, we tested if microglia secrete a neurovascular mediator matrix metalloproteinase-9 (MMP-9) after phagocytosis in vitro. Primary microglial cultures were prepared from neonatal rat brains. Cultured microglia phagocytosed Escherichia coli bioparticles within 2 hr after incubation and started to secrete MMP-9 at around 12 hr after the phagocytosis. A TLR4 inhibitor TAK242 suppressed the E. coli-bioparticle-induced MMP-9 secretion. However, TAK242 did not change the engulfment of E. coli bioparticles in microglial cultures. Because lipopolysaccharides (LPS), the major component of the outer membrane of E. coli, also induced MMP-9 secretion in a dose–response manner and because the response was inhibited by TAK242 treatment, we assumed that the LPS-TLR4 pathway, which was activated by adhering to the substance, but not through the engulfing process of phagocytosis, would play a role in releasing MMP-9 from microglia after E. coli bioparticle treatment. To support the finding that the engulfing step would not be a critical trigger for MMP-9 secretion after the event of phagocytosis in microglia, we confirmed that cell debris and amyloid beta were both captured into microglia via phagocytosis, but neither of them induced MMP-9 secretion from microglia. Taken together, these data demonstrate that microglial response in MMP-9 secretion after phagocytosis differs depending on the types of particles/substances that microglia encountered.  相似文献   
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Worldwide, the hepatitis B virus (HBV) and the hepatitis C virus (HCV) cause, respectively, 600,000 and 350,000 deaths each year. Viral hepatitis is the leading cause of cirrhosis and liver cancer, which in turn ranks as the third cause of cancer death worldwide. Within the WHO European region, approximately 14 million people are chronically infected with HBV, and nine million people are chronically infected with HCV. Lack of reliable epidemiological data on HBV and HCV is one of the biggest hurdles to advancing policy. Risk groups such as migrants and injecting drug users (IDU) tend to be under-represented in existing prevalence studies; thus, targeted surveillance is urgently needed to correctly estimate the burden of HBV and HCV. The most effective means of prevention against HBV is vaccination, and most European Union (EU) countries have universal vaccination programmes. For both HBV and HCV, screening of individuals who present a high risk of contracting the virus is critical given the asymptomatic, and thereby silent, nature of disease. Screening of migrants and IDUs has been shown to be effective and potentially cost-effective. There have been significant advances in the treatment of HCV and HBV in recent years, but health care professionals remain poorly aware of treatment options. Greater professional training is needed on the management of hepatitis including the treatment of liver cancer to encourage adherence to guidelines and offer patients the best possible outcomes. Viral hepatitis knows no borders. EU Member States, guided by the EU, need to work in a concerted manner to implement lasting, effective policies and programmes and make tackling viral hepatitis a public health priority.  相似文献   
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The aim of this qualitative study was to identify the motivational factors that influence cancer survivors to participate and adhere to the fear of cancer recurrence (FCR) FORT randomized controlled trial (RCT). Fifteen women diagnosed with breast and gynecological cancer who took part in the FORT RCT were interviewed about their experience to consent and adhere to the trial. The transcribed interviews were content analyzed within a relational autonomy framework. The analysis revealed that the participants’ motivation to consent and adhere to the FORT RCT was structured around thirteen subthemes grouped into four overarching themes: (1) Personal Influential Factors; (2) Societal Motivations; (3) Structural Influences; and (4) Gains in Emotional Support. The unique structures of the trial such as the group format, the friendships formed with other participants in their group and with the group leaders, and the right timing of the trial within their cancer survivorship trajectory all contributed to their motivation to consent and adhere to the FORT RCT. While their initial motivation to participate was mostly altruistic, it was their personal gains obtained over the course of the trial that contributed to their adherence. Potential gains in emotional and social support from psycho-oncology trials should be capitalized when approaching future participants as a mean to improve on motivations to consent and adhere.  相似文献   
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恩替卡韦与拉米夫定治疗HBeAg阴性慢性乙型肝炎的对照研究   总被引:42,自引:1,他引:42  
Lai  CL  Shouval  D  Lok  AS  陈楠 《世界感染杂志》2006,6(4):396-396
Ⅱ期临床试验已经证实恩替卡韦是一种治疗HBeAg阴性慢性乙型肝炎有效和可选择的抗病毒药物。采用双盲法将648例未曾接受过核苷类药物治疗的HBeAg阴性慢性乙型肝炎随机分配进入恩替卡韦(0.5mg/d)治疗组或拉米夫定(100mg/d)治疗组,疗程至少52wk。  相似文献   
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We examined the effects of dietary fats on methylmercury (MeHg)-induced systemic oxidative stress and oxidative DNA damage in liver and kidney of male Sprague-Dawley rats. Rats were treated with a casein-based purified isocaloric diet containing 15% by weight soy oil, docosahexaenoic acid (DHA), seal oil, fish oil, or lard for 28 days, and then gavaged with 0, 1, or 3 mg MeHg/kg BW/day for 14 days. Urine was analyzed for 8-hydroxydeoxyguanosine (8-OHdG) and isoprostane, and serum for total antioxidant capacity (TAC). Liver and kidney were analyzed immunohistochemically for 8-OHdG. Both diet and MeHg showed significant main effects on some of these markers. As compared with the vehicle control, 3 mg MeHg/kg BW significantly increased urinary 8-OHdG in the lard group, urinary isoprostane in the DHA, seal oil, and fish oil groups, while significantly decreasing serum TAC in the lard and fish oil groups. In all dietary groups, 8-OHdG positive staining was located mainly in the nuclei of various cell types in liver and kidney. MeHg expressed a significant main increasing effect on 8-OHdG-positive cells in kidney. These results suggest that both dietary fats and MeHg are important mediators of systemic oxidative stress and oxidative DNA damage.  相似文献   
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