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31.
A. Cattapan K. Browne D.M. Halperin A. Di Castri P. Fullsack J. Graham J.M. Langley B.A. Taylor S.A. McNeil S.A. Halperin 《Vaccine》2019,37(2):289-295
Introduction/Hypothesis
Recruitment of participants into phase 1 vaccine clinical trials can be challenging since these vaccines have not been used in humans and there is no perceived benefit to the participant. Occasionally, as was the case with a phase 1 clinical trial of an Ebola vaccine in Halifax, Canada, during the 2014–2016 West African Ebola virus outbreak, recruitment is less difficult. In this study, we explored the motivations of participants in two phase 1 vaccine trials that were concurrently enrolling at the same centre and compared the motivations of participants in a high-profile phase 1 Ebola vaccine trial to those in a less high-profile phase 1 adjuvanted seasonal influenza vaccine study.Methods
An online survey which included participants’ prior experience with clinical trials, motivations to participate (including financial incentives), and demographic information was developed to examine the motivations of healthy participants in two phase 1 clinical vaccine trials conducted at the Canadian Center for Vaccinology in Halifax, Nova Scotia. Participants were invited via email to complete the online survey. Readability and clarity were assessed through pilot testing.Results
A total of 49 (55.7%) of 88 participants of the two studies completed the survey (22 [55%] of 40 participants from the Ebola vaccine study and 27 [56.3%] of 48 from the adjuvanted influenza vaccine study). Motivations that were most frequently ranked among participants' top three in both trials were (1) wanting to contribute to the health of others, (2) wanting to participate in something important, (3) wanting to contribute to the advancement of science, and (4) wanting to receive an incentive such as money or a tablet.Conclusions/Recommendations
Although media attention and financial compensation were more often cited by Ebola vaccine trial participants as a reason to participate, both altruistic and self-interested factors were important motivations for participants in their decision to participate in a phase 1 vaccine clinical trial. 相似文献32.
目的 了解平顶山市8岁学龄儿童龋病流行状况,探讨影响龋病发生发展的危险因素。 方法 参考“第三次全国口腔健康调查”的标准,采用分层整群抽样的方法,对1 762名适龄儿童进行口腔检查和问卷调查。 结果 平顶山市8岁学龄儿童患龋率84.68%,龋均4.79,城乡结合区域及农村儿童患龋率和龋均明显高于城市,差异有统计学意义(P<0.05);乳、恒牙患龋率分别为83.65%、25.77%;城乡类型(OR=22.42)、家庭收入(OR=10.21)、睡前是否有吃零食习惯(OR=8.01)、吃完零食是否刷牙(OR=6.00)、进食甜食频率(OR=8.28)、刷牙方法(OR=8.88)、家长是否检查刷牙效果(OR=9.15)是影响患龋率的因素。 结论 平顶山市农村及城乡结合区域儿童患龋率较高,应加强口腔健康教育和龋病预防控制工作。 相似文献
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Jae Eun Choi Tyler Werbel Zhenping Wang Chia Chi Wu Tony L. Yaksh Anna Di Nardo 《Journal of dermatological science》2019,93(1):58-64
Background
Rosacea is a chronic inflammatory skin condition whose etiology has been linked to mast cells and the antimicrobial peptide cathelicidin LL-37. Individuals with refractory disease have demonstrated clinical benefit with periodic injections of onabotulinum toxin, but the mechanism of action is unknown.Objectives
To investigate the molecular mechanism by which botulinum toxin improves rosacea lesions.Methods
Primary human and murine mast cells were pretreated with onabotulinum toxin A or B or control. Mast cell degranulation was evaluated by β-hexosaminidase activity. Expression of botulinum toxin receptor Sv2 was measured by qPCR. The presence of SNAP-25 and VAMP2 was established by immunofluorescence. In vivo rosacea model was established by intradermally injecting LL-37 with or without onabotulinum toxin A pretreatment. Mast cell degranulation was assessed in vivo by histologic counts. Rosacea biomarkers were analyzed by qPCR of mouse skin sections.Results
Onabotulinum toxin A and B inhibited compound 48/80-induced degranulation of both human and murine mast cells. Expression of Sv2 was established in mouse mast cells. Onabotulinum toxin A and B increased cleaved SNAP-25 and decreased VAMP2 staining in mast cells respectively. In mice, injection of onabotulinum toxin A significantly reduced LL-37-induced skin erythema, mast cell degranulation, and mRNA expression of rosacea biomarkers.Conclusions
These findings suggest that onabotulinum toxin reduces rosacea-associated skin inflammation by directly inhibiting mast cell degranulation. Periodic applications of onabotulinum toxin may be an effective therapy for refractory rosacea and deserves further study. 相似文献35.
[目的]基于中医"通肾络、益脾肾"治法,探讨通络益肾方对体外高糖培养的小鼠肾小球足细胞自噬和凋亡蛋白SIRT1、BNIP3、P62、Bax表达的调控影响。[方法]成熟无特定病原体(SPF)级SD雄性大鼠40只,随机分为正常组、中药高、中、低剂量组各10只。按照人与大鼠体表面积折算方法计算出大鼠所需中药灌胃浓度:高剂量浓度4.76 g/mL、中剂量浓度2.38 g/mL、低剂量浓度1.19 g/m L,灌胃10 d取含药血清备用。足细胞分6组,正常组5.6 mmol/L葡萄糖+10%正常大鼠血清、高糖组30mmol/L葡萄糖+10%正常大鼠血清、通络益肾方含药血清高、中、低干预组30 mmol/L葡萄糖+10%高、中、低剂量大鼠血清、高渗组甘露醇24.5 mmol/L+10%正常大鼠血清。细胞培养48 h后收集,Hoechst33342荧光染色,观察各组足细胞凋亡状况及形态变化;流式细胞仪检测足细胞凋亡率;Western Blot检测细胞内自噬标志蛋白SIRT1、P62及促凋亡蛋白BNIP3、Bax表达水平。[结果]流式细胞仪检测结果显示通络益肾方中、低剂量组可降低高糖诱导的足细胞凋亡率(P0.01或P0.05),高剂量组不能改善凋亡情况(P0.05);Hoechst33342荧光染色观察结果也证实通络益肾方中、低剂量组可降低高糖诱导的足细胞凋亡率;蛋白印迹结果显示,与高糖组相比,通络益肾方中、低剂量组自噬标志蛋白SIRT1表达升高,自噬标志蛋白P62及促凋亡蛋白BNIP3、Bax蛋白表达下降(P0.05或P0.01),高剂量组SIRT1、BNIP3、P62、Bax蛋白表达未见明显改变(P0.05)。[结论]中剂量、低剂量通络益肾方能够启动细胞自噬减少高糖刺激下体外培养足细胞凋亡,降低细胞凋亡率及凋亡蛋白的表达。 相似文献
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Evaluation of training nurses to perform semi‐automated three‐dimensional left ventricular ejection fraction using a customised workstation‐based training protocol
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39.
目的:评定LC-MS/MS法测定人血浆中布康唑浓度的不确定度。方法:分析测定过程中不确定度的来源,包括对照品的称量、仪器误差、标准溶液的配制、含药血浆样品的配制、血浆样品的处理、标准曲线的拟合、基质效应、重复性等,评定各来源分量的不确定度,计算合成不确定度和扩展不确定度。结果:人血浆中低(60.0 pg·mL-1)、中(600.0 pg·mL-1)、高(6 400.0 pg·mL-1)浓度布康唑的扩展不确定度分别为5.62,63.90,626.26 pg·mL-1(k=2,P=95%)。结论:LC-MS/MS法测定人血浆中布康唑浓度的不确定度主要由基质效应、血浆样品的处理(提取回收率),仪器误差、重复性(精密度)引入。 相似文献
40.
目的 评价NITI悬臂梁在矫正舌倾下颌磨牙中的临床效果。方法 选择16例单侧下颌第二磨牙舌倾的病例为研究对象,带垫铸造支架连接双侧下颌后牙,提供颌内支抗、解除咬合锁结,0.018英寸×0.025英寸或0.019英寸×0.025英寸NITI悬臂梁提供颊向旋转力矩和压低力。采用Graphpad Prism 6.0 软件对治疗前、后所测数据进行配对 t 检验。结果 所有患牙均获得直立,牙轴变化24°±1.2°(P<0.01),近中舌尖到正中矢状面垂直距离变化(3±0.8) mm(P<0.05),牙周状况良好,咬合关系稳定。结论 铸造支架联合NITI 悬臂梁可提供有效力学机制,矫正舌倾下颌磨牙。 相似文献