What determines skin sensitization potency: Myths,maybes and realities. The 500 molecular weight cut‐off: An updated analysis

It is widely accepted that substances must have a molecular weight (MW) < 500 to penetrate effectively through the skin to induce sensitization. Roberts et al . (2012. Contact Dermatitis 68: 32–41) evaluated a data set of 699 substances taken from the TIMES‐SS expert system and identified that of the 13 substances with a MW > 500, five were sensitizers. This provided good evidence to refute such a MW 500 threshold. While Roberts et al . (2012) made a convincing case that the MW > 500 cut‐off was not a true requirement for sensitization, the number of counter examples identified were too few to draw any statistical conclusions. This updated analysis systematically interrogated a large repository of sensitization information collected under the EU REACH regulation. A data set of 2904 substances that had been tested for skin sensitization, using guinea pigs and/or mice were collected. The data set contained 197 substances with a MW > 500; 33 of these were skin sensitizers. Metal containing complexes, reaction products and mixtures were excluded from further consideration. The final set of 14 sensitizers substantiated the original findings. The study also assessed whether the same reaction chemistry principles established for low MW sensitizers applied to chemicals with a MW > 500. The existing reaction chemistry considerations were found appropriate to rationalize the sensitization behaviour of the 14 sensitizers with a MW > 500. The existence of the MW 500 threshold, based on the widespread misconception that the ability to penetrate efficiently the stratum corneum is a key determinant of skin sensitization potential and potency, was refuted. Copyright © 2016 John Wiley & Sons, Ltd.     

三维图像及宫腹腔镜手术录像在留学生教学中的应用

目的 探讨三维图像及宫腹腔镜手术录像在留学生教学中的应用。方法 选取山东第一医科大学国际交流学院2018—2019 学年的91 名留学生,将其随机分为两组,分别为对照组（n=45）和试验组（n=46）,对照组采用传统教学方法,试验组将“三维图像”及腹腔镜录像应用于教学过程中,通过发放问卷、实践及理论考试成绩及师生访谈等方式进行效果评价。结果 试验组学生期末笔试及格率为100.0%,高于对照组的84.4%,差异有统计学意义（P<0.05）,问卷结果提示超过50%的学生认为采用三维图像及宫腹腔镜手术录像的教学方式优于传统教学方式,师生访谈提示试验组学生对教学方式的满意度为95.65%,高于对照组的64.44%,差异有统计学意义（P<0.05）。结论 三维图像及宫腹腔镜手术录像能够真实有效显示盆底解剖学形态、结构及病理变化,有利于提高留学生教学的教学质量和教学效率。     

新型冠状病毒肺炎流行期间来华医学留学生心理健康状况调查研究

目的了解新型冠状病毒肺炎流行期间来华医学留学生的心理健康状况,为提高来华医学留学生的心理健康水平提供参考依据。方法采用症状自评量表英文版(Symptom Checklist 90,SCL-90)对118名来华医学留学生进行线上调查。使用SPSS 19.0对数据进行统计分析,组间比较采用独立样本t检验和单因素方差分析。结果通过对收集数据进行独立样本t检验以及单因素方差分析得出:新型冠状病毒肺炎流行期间,来华医学留学生SCL-90各因子得分均显著高于中国青年常模(P<0.001)。得分前四位的次序为:强迫症状>偏执>人际关系敏感>抑郁。来华医学留学生SCL-90筛查阳性率为40.4%。男留学生各因子得分显著高于女留学生(P<0.01),现居住在中国境外的留学生的得分显著高于居住在中国境内和校内的留学生(P<0.001)。结论新型冠状病毒肺炎流行期间,高校应高度重视来华医学留学生的心理健康状况,分别给予滞留在中国境外的留学生和处在封闭式管理下的校内留学生有针对性的心理疏导和干预。     

肝脏动、静脉相CT图像配准与融合方法研究

目的 研究肝脏CT扫描序列图像轮廓提取、配准与融合问题.方法 采用图像滤波去噪、增强图像边缘及提取图像外轮廓等方法对CT序列图像进行预处理.对肝脏CT扫描序列图像动脉相位期与静脉相位期的图像轮廓进行配准,选取最优配准参数确定不同相位期图像的对应关系,以实现配准.将配准后对应的动、静脉相位期图像融合.结果 融合后的图像展现了同一位置不同相位期肝脏动、静脉的情况.结论 配准、融合后的图像能提供更加丰富的信息,可为医生临床诊断提供参考.     

日本生物类似药注册监管政策绩效评价研究及启示

目的:为完善我国生物类似药的注册监管提供参考。方法:以日本生物类似药研发注册审评政策为研究对象,分析其注册审评流程及核心特征,并探讨政策实施效果。结果与结论:日本注册监管政策有助于提高生物类似药的可获得性与可支付性,同时促进了生物医药产业的健康发展。启示:我国可以引入适度简化原则,减免部分研发程序和申报资料要求,促进生物类似药的研发上市;沿用新药审评程序,确保生物类似药研发注册的稳定性。     

高等医学院校留学生心血管内科的教学经验和体会

目前中国的医学教育已经进入了飞速前进的时代,高等医学教育需要与国际接轨并逐步采纳国际标准。医学类留学生的教育水平体现了高等医科院校的国际化水平。2009年至今,安徽医科大学国际教育学院招收了来自东南亚国家和非洲地区的留学生共计170多名。2012年起留学生已经陆续进入临床课程学习阶段,为提高国际医学类留学生教育的教学水平,笔者针对留学生特点和心血管内科学教学特点,就教学中面临的问题和如何改进教学水平进行阐述。     

Embryo-fetal development toxicity of honokiol microemulsion intravenously administered to pregnant rats

The aim of this study was to evaluate the embryo-fetal development toxicity of honokiol microemulsion. The drug was intravenously injected to pregnant SD rats at dose levels of 0, 200, 600 and 2000 μg/kg/day from day 6–15 of gestation. All the pregnant animals were observed for body weights and any abnormal changes and subjected to caesarean-section on gestation day (GD) 20; all fetuses obtained from caesarean-section were assessed by external inspection, visceral and skeletal examinations. No treatment-related external alterations as well as visceral and skeletal malformations were observed in honokiol microemulsion groups. There was no significant difference in the body weight gain of the pregnant rats, average number of corpora lutea, and the gravid uterus weight in the honokiol microemulsion groups compared with the vehicle control group. However, at a dose level of 2000 μg/kg/day, there was embryo-fetal developmental toxicity observed, including a decrease in the body length and tail length of fetuses. In conclusion, the no-observed–adverse-effect level (NOAEL) of honokiol microemulsion is 600 μg/kg/day, 75 times above the therapeutic dosage and it has embryo-fetal toxicity at a dose level of 2000 μg/kg/day, which is approximately 250 times above the therapeutic dosage.     

Case studies putting the decision-making framework for the grouping and testing of nanomaterials (DF4nanoGrouping) into practice

Case studies covering carbonaceous nanomaterials, metal oxide and metal sulphate nanomaterials, amorphous silica and organic pigments were performed to assess the Decision-making framework for the grouping and testing of nanomaterials (DF4nanoGrouping). The usefulness of the DF4nanoGrouping for nanomaterial hazard assessment was confirmed. In two tiers that rely exclusively on non-animal test methods followed by a third tier, if necessary, in which data from rat short-term inhalation studies are evaluated, nanomaterials are assigned to one of four main groups (MGs). The DF4nanoGrouping proved efficient in sorting out nanomaterials that could undergo hazard assessment without further testing. These are soluble nanomaterials (MG1) whose further hazard assessment should rely on read-across to the dissolved materials, high aspect-ratio nanomaterials (MG2) which could be assessed according to their potential fibre toxicity and passive nanomaterials (MG3) that only elicit effects under pulmonary overload conditions. Thereby, the DF4nanoGrouping allows identifying active nanomaterials (MG4) that merit in-depth investigations, and it provides a solid rationale for their sub-grouping to specify the further information needs. Finally, the evaluated case study materials may be used as source nanomaterials in future read-across applications. Overall, the DF4nanoGrouping is a hazard assessment strategy that strictly uses animals as a last resort.     

自身免疫疾病相关检测试剂注册技术要点分析

XIE Yi(Center for Medical Device Evaluation,NMPA,Beijing 100081,China)     

多模式医学图像的融合和配准技术

医学影像工程不断发展,出现了很多先进的成像设备,有力地支持了医学诊断和治疗。而以计算机技术为基础的成像后处理技术进一步提高了诊疗的可靠性。我们着重介绍了多模式医学图像融合和配准的技术内容和应用。