The presence of negative air ions (NAI) is suggested to be a beneficial factor in improving psychological status and used in treating depression as an alternative approach. However, more biological evidence from animal models is needed to ensure the effects of NAI on the mood regulation, through which can facilitate identification of possible underlying mechanisms. In this study, the chronic mild stress (CMS) protocol was used to induce depressive-like behaviors in mice, and the effects of NAI exposure on CMS-induced depression-like behaviors were examined. Thirty-day NAI exposure prevented the CMS-induced depression-like behaviors as shown by the restoration of sucrose preference and reduced immobility time in the tail suspension test. In addition, the elevation of serous corticosterone was present in CMS-treated mice but not existed in those with the NAI exposure. Furthermore, we observed altered ratios of some cytokines secreted by type 1 T helper (Th1) cells and Th2 cells in CMS-treated mice, but it could be restored after NAI exposure. In conclusion, NAI intervention is able to ameliorate CMS-induced depression-like behaviors in mice, and this effect is associated with the alteration of corticosterone and functional rebalance between Th1 and Th2 cells.

目的 探讨医学本科生临终生命关怀知识和态度现状,并分析其影响因素.方法 采用便利抽样法和问卷调查法对兰州大学2016—2020级临床医学专业本科生进行线上问卷调查,共发放问卷200份,收回有效问卷189份(94.5％).结果 医学本科生临终生命关怀知识处于中等偏高水平,不同年级学生知识掌握程度差异具有统计学意义(P<0.5),高年级学生对临终生命关怀的意义和内容掌握更好.接触临终患者个数、是否自愿学医、是否同意在医学教育中加入临终生命关怀教育、是否愿意做临终生命关怀志愿者对医学生临终生命关怀知识水平有一定的影响.结论 高校医学本科生已认识到临终生命关怀的重要性,参与临终生命关怀服务的意愿较强,态度较为积极,但相关知识学习途径和实践经验有限.高校应积极开设临终生命关怀类课程,加强生命教育,提高医学生临终生命关怀知识水平和应用能力.

目的 通过调查孕妇生活居住环境情况,了解母体血镍、砷水平对胎儿生长发育的影响,为阐明镍、砷对胎儿生长发育的影响提供依据.方法 选择甘肃省某重金属污染地区及其毗邻、位于其上风侧的另一地区作为研究地区(污染区空气PM2.5中镍、砷水平高于对照区),通过问卷调查收集孕妇的基本情况,利用B型超声检测孕中期胎儿双顶径、头围、股骨长度、腹围、胎心率大小,采用电感耦合等离子质谱仪测定孕中期孕妇静脉血镍(Ni)、砷(As)水平.分别以对照区及污染区共计82名研究对象的母血镍、砷水平中位数为截点,将孕妇及宫内胎儿按孕妇静脉血镍、砷水平分为低、高金属暴露组.结果 高砷暴露组来自于污染区的孕妇多于低砷暴露组(χ2=14.07,P<0.01).高镍组胎儿头围(201 mm)、腹围(168 mm)中位数低于低镍组头围(210 mm)和腹围(182 mm)(Z值分别为-2.53、-3.25;P<0.05);高砷组胎儿头围(204 mm)、股骨长度(38 mm)中位数小于低砷组头围(210 mm)和股骨长度(39 mm)(Z值分别为-2.03、-2.18;P<0.05).胎儿头围、腹围与孕妇静脉血镍水平存在负相关关系(t值分别为-4.76、-5.45,P<0.05).结论 孕妇暴露于镍、砷污染的空气环境可以影响宫内胎儿的生长发育,孕中期孕妇静脉血镍含量与孕中期胎儿头围和腹围存在负相关.

目的 探讨孕中期、孕晚期、分娩时孕妇镍(Ni)、砷(As)暴露与新生儿氧化应激指标关系及其密切程度.方法 于2013—2016年选取甲地(有矿开采)和乙地(无矿开采)孕中期(71对)、孕晚期(171对)、分娩时(206对)孕妇和新生儿作为研究对象.收集孕妇基本资料并在孕中期、孕晚期、分娩时采集孕妇静脉血和新生儿脐带血.以电感耦合等离子质谱法(ICP-MS)测定孕妇静脉血Ni、As水平,酶联免疫吸附法(ELISA)检测新生儿脐带血氧化应激指标8-异构前列腺素2α(8-epi-PGF2α)、3-硝基酪氨酸(3-NT)及8-羟基脱氧鸟苷(8-OHdG)含量.多重线性回归分析孕期孕妇静脉血Ni、As暴露水平与新生儿脐带血氧化应激指标关系.结果 除孕晚期Ni外,孕中期、分娩时甲地孕妇静脉血Ni、As水平显著高于乙地(P<0.05);除孕中、晚期8-epi-PGF2α外,孕中期、孕晚期、分娩时甲地新生儿脐带血3-NT、8-OHdG、8-epi-PGF2α高于乙地(P<0.05).多重线性回归分析显示,孕中期孕妇静脉血Ni[β:0.110(95％CI:0.019～0.202)]、As[β:0.290(95％CI:0.115～0.466)]与3-NT呈正相关;分娩时孕妇静脉血Ni与3-NT无相关性[β:0.044(95％CI:-0.004～0.092)];孕中期、孕晚期、分娩时孕妇静脉血Ni、As与8-epi-PGF2α、8-OHdG均无相关性(P>0.05).结论 孕期镍、砷暴露与新生儿脐带血氧化应激指标有一定关联,可能导致氧化应激,孕中期金属暴露更适合作为胎儿内暴露生物标志.

The purpose of the present study is to explore the associations between novel coronavirus disease 2019 (COVID-19) case counts and meteorological factors in 30 provincial capital cities of China. We compiled a daily dataset including confirmed case counts, ambient temperature (AT), diurnal temperature range (DTR), absolute humidity (AH) and migration scale index (MSI) for each city during the period of January 20th to March 2nd, 2020. First, we explored the associations between COVID-19 confirmed case counts, meteorological factors, and MSI using non-linear regression. Then, we conducted a two-stage analysis for 17 cities with more than 50 confirmed cases. In the first stage, generalized linear models with negative binomial distribution were fitted to estimate city-specific effects of meteorological factors on confirmed case counts. In the second stage, the meta-analysis was conducted to estimate the pooled effects. Our results showed that among 13 cities that have less than 50 confirmed cases, 9 cities locate in the Northern China with average AT below 0 °C, 12 cities had average AH below 4 g/m3, and one city (Haikou) had the highest AH (14.05 g/m3). Those 17 cities with 50 and more cases accounted for 90.6% of all cases in our study. Each 1 °C increase in AT and DTR was related to the decline of daily confirmed case counts, and the corresponding pooled RRs were 0.80 (95% CI: 0.75, 0.85) and 0.90 (95% CI: 0.86, 0.95), respectively. For AH, the association with COVID-19 case counts were statistically significant in lag 07 and lag 014. In addition, we found the all these associations increased with accumulated time duration up to 14 days. In conclusions, meteorological factors play an independent role in the COVID-19 transmission after controlling population migration. Local weather condition with low temperature, mild diurnal temperature range and low humidity likely favor the transmission.

[背景]孕期重金属环境暴露可以影响不同孕期胎儿生长发育情况,重金属暴露对哪一孕期影响最大以及综合评判孕期胎儿生长发育情况与脐带血重金属水平之间的相关关系的研究较为少见.[目的]了解重金属暴露状态下,不同孕期胎儿生长发育情况及与脐带血重金属水平之间的相关关系.[方法]2013年1月至2016年12月期间,选择甘肃省某重金属污染地区(污染区)及其毗邻的位于污染地区上风侧的另一地区(对照区)作为研究地区,经知情同意后,纳入自愿配合且年龄在22～35周岁、在研究地点连续居住两年以上的单胎妊娠孕产妇.通过问卷调查收集孕妇的基本情况,利用B型超声检查不同时期胎儿双顶径、股骨长度、胎心率等,采用电感耦合等离子质谱仪测定所有孕妇分娩时新生儿脐带血镍、铜、砷水平,采用典型相关分析胎儿双顶径、股骨长度、胎心率与脐带血镍、铜、砷水平两组指标间的相关性.[结果]孕中、晚期和分娩时分别纳入研究对象42、58、71名(污染区)和58、91、169名(对照区).两地区孕妇的基本情况除了孕晚期、分娩时的被动吸烟情况[污染区(84.5％、85.9％)高于对照区(44.0％、47.3％)(均P＜0.001)]和孕中期、分娩时的孕妇妊娠期合并症[污染区(40.5％、38.0％)高于对照区(19.0％、17.8％) (P=-0.018,=-0.001)]及分娩时孕妇居住地距马路≤300m者和孕妇服用药物的比例[污染区(60.6％、29.6％)高于对照区(45.0％、12.4％) (P=0.027,P=0.001)]差异存在统计学意义外,其他方面差异均无统计学意义.孕中期、孕晚期、分娩时入选的污染区新生儿脐带血砷水平(0.77、0.75、0.73μg·L-1)高于对照区(0.29、0.34、0.35 μg·L-1)(P＜0.001);孕中期、孕晚期、分娩时污染区胎儿股骨长度(35.0、60.0、70.0 mm)小于对照区(41.5、63.0、72.0 mm) (P＜0.01).孕中期胎儿生长发育与新生儿脐带血重金属水平存在典型相关关系,其典型相关关系式为:U1=0.617X1+0.349X2-0.430X3 (X1-3分别为双顶径、股骨长度、胎心率);W1=-0.545Y-0.109Y2-0.897Y3(y1-3分别为镍、铜、砷水平).即胎儿双顶径、股骨长度与新生儿脐带血镍、铜、砷水平为负相关,胎儿胎心率与新生儿脐带血镍、铜、砷水平为正相关;胎儿双顶径、股骨长度与新生儿脐带血砷水平的相关性最密切.[结论]脐带血的重金属水平作为内暴露剂量与孕中期胎儿双顶径、股骨长度存在负相关,孕期重金属暴露对孕中期胎儿的不良影响较大.