2007年重庆市璧山县和云阳县抽样地区环境碘含量调查分析

为了解重庆市抽样地区自然环境中的碘含量,为碘盐的合理摄入和防治碘相关疾病提供依据,采用多级整群随机抽样法,选择重庆市渝东地区云阳县和渝西地区璧山县为调查点,在两县经济状况中等的乡镇各抽取3所乡镇小学的8～10岁儿童各30名作为调查对象,以直接滴定法(GB/T13025.7-1999)检测了其家庭食用盐碘含量;采用随机抽样方法抽取两县居民饮用水样和土壤样,以GB5750-85中砷铈催化分光光度法测定了水碘含量,反向放大比色法测定了土壤碘含量。结果表明,检测两县居民食盐样本556份,璧山县与云阳县食盐碘均数分别为30.41和35.78mg/kg;抽取两县居民饮用水样87份,两县水碘中位数分别为6.50和2.78μg/L;水碘含量10μg/L的水样分别占73.33%和100%;抽取两县浅表层土壤样品88份,两县土壤碘中位数分别为8.20和7.56mg/kg。提示两抽样县均属于碘缺乏地区,需要通过食盐加碘防治碘缺乏病。可根据各地区具体情况,考虑适当调整食盐含碘量。     

三明市梅列区2004—2015年碘缺乏病防治情况分析

目的分析梅列区2004—2015年碘缺乏病病情及盐碘监测情况,评估消除碘缺乏病工作。方法根据《福建省碘盐监测实施细则》进行监测。结果 2007年、2013年、2015年8~10岁儿童甲状腺肿大5%;居民户碘盐覆盖率95%,合格碘盐食用率90%;2007年、2011、2015年抽查8~10岁儿童,尿碘100μg/L以下的比率50%,尿碘50μg/L以下的比率20%;2015年开始监测孕妇尿碘,尿碘小于150μg/L的孕妇占62.38%,尿碘中位数122.6μg/L。结论通过推广普及合格碘盐和健康促进,12年来梅列区居民户碘盐及儿童尿碘达到国家消除碘缺乏病标准,而孕妇尿碘水平偏低。今后要深入持久地普及合格碘盐和开展健康教育,增强居民的自我保健意识,合理食用碘盐,提高孕妇尿碘水平。     

哈尔滨市平房区碘缺乏病的自我考评结果分析

对哈尔滨市平房区7～10岁学龄儿童尿碘、甲状腺肿及用户碘盐进行调查，其结果为：尿碘中位数为315μg／L，＜50μg／L者占5．7％，＜100μg／L者占10．6％；甲状腺肿大率为21．80％；盐碘中位数为46．4×10-6，＜20×10－6者占3．9％，按照WHO、UNICEF、ICCIDD三个国际组织提供的考核评估标准，尿碘、盐碘水平已达标，但甲状腺肿大率未达标。     

孝感市1996年碘缺乏病防治监测结果分析

1996年9月采用PPS法在孝感市范围内对碘缺乏病(IDD)防治工作作了抽样监测。8～10岁儿童甲状腺肿大率(TGR)842%,其中查出Ⅱ°肿大3人,TGR≤5%的点占5333%;尿碘值<100μg/L占417%;M值为3855μg/L;居户盐碘2388×10-6±1216×10-6,<20×10-6的点占1667%,非碘盐占1167%。监测结果表明,本市8～10岁儿童TGR较1994年有下降;碘营养缺乏状况得到改善,碘代谢水平已达到IDD消除标准;碘盐的合格率仅7658%,离IDD消除标准还差近14个百分点。在本市IDD防治工作中实施的以供应加碘盐为主的综合防治措施是行之有效的,并取得了一定效果。揭示在今后的防治中,要进一步抓紧以供应加碘盐为主的综合防治措施。     

重庆地区食盐加碘含量下调的可行性研究

为探讨重庆市食盐加碘含量下调的可行性,分析比较了重庆市碘盐和碘缺乏病监测结果(儿童甲状腺肿大率、智商、尿碘、家庭食用碘盐)。结果表明,碘盐含量稳定,全民食盐加碘防治碘缺乏病的措施成功,但尿碘水平高于适宜水平,甲肿率居高不下,可能存在补碘过量,引起高碘性甲状腺肿大。为有效控制甲肿率和尿碘水平,建议下调食盐加碘含量。     

科学补碘:消除碘缺乏病的成败关键

碘对甲状腺功能具有双向作用,在消除碘缺乏病的同时,切不可忽略全民食盐加碘后高碘甲状腺病的防治。分别从水碘和尿碘两个方面论述了碘与甲状腺病之间的双向关系,并根据流行病学调查数据和全国碘缺乏病监测数据确定了盐碘与尿碘之间的数学关系,计算了食盐碘含量的最适宜范围,提出了下调食盐碘含量、设计区域化碘盐和补碘个性化的科学补碘新策略。     

重庆地区特需人群碘营养水平及影响因素分析

为了解重庆地区孕妇、婴儿及其母亲碘营养现状,给该地区实施科学补碘提供科学依据,采用砷铈催化分光光度法测定了当地水碘和孕妇、婴儿及其母亲的尿碘,电化学发光法检查了孕妇甲状腺功能.结果表明,水碘为5.99 μg/L,孕妇、乳母、婴儿尿碘中位数为203.80 μg/L、218.3 μg/L、288.4 μg/L,FT3、FT4为(3.94±0.59) pmol/L、(12.44±2.30) pmol/L;逐步回归分析表明,碘营养与文化程度、食用优质蛋白及富硒食品呈正相关,母亲缺碘是小孩缺碘的危险因素之一.提示特需人群的碘营养水平适宜,文化程度、食用优质蛋白及富硒食品为主要影响因素,婴儿尿碘与母亲相关.     

襄樊市学龄儿童碘营养现状调查

按东西南北中五个方位抽取了襄樊市７０所小学２８００名８－１０岁儿童进行了碘营养状况调查。以解诊和Ｂ超法检查甲状腺肿大率为主要指标,盐碘含量、尿碘水平为重要参考指标。结果表明：８－１０岁儿童甲肿率触诊法和Ｂ超法分别为１０．２５％和８．２５％,两者符合率为９６．６４％,甲肿率均超过５％,尿碘中位数为４３９．８１μｇ／Ｌ,尿碘值大于１００μｇ／Ｌ得占９６．６７％;儿童家中食盐含碘中位数为３１．３０＊１０     

新生儿及其乳母碘营养状况探讨

为了解杭州部分地区现行加碘盐含量是否满足孕妇分娩时碘营养需求,采用碘铈催化分光光度法对79对新生儿及其母亲尿碘进行了检测。结果表明,新生儿组尿碘明显高于其母亲组(t=22.62,P<0.01)。新生儿的尿碘与其母亲尿碘含量呈正相关(r=0.862,P<0.01),母亲组尿碘小于100μg/L,有9人,占本组11.4%。新生儿组有10人及其母亲组有57人,尿碘在100~200μg/L,分别占本组的12.7%和72.2%。表明母亲组碘营养轻度不足比例较高。     

毛细管区带电泳法测定冬虫夏草及鹿茸制品中核苷和碱基成分

应用毛细管区带电泳法测定分别以冬虫夏草菌丝体粉和鹿茸血为主要原料制品中的多种核苷和碱基成分。对实验条件进行了优化,结果表明,以20mmol/L硼砂-15mmol/Lβ-环糊精为缓冲溶液(pH=9.4),分离电压22kV,检测波长254nm,电动进样为10kV、5s时,在10min内同时分离测定了虫草素、腺嘌呤、鸟嘌呤、尿嘧啶、腺苷、次黄嘌呤、尿苷、鸟苷和肌苷。各组分在0.2～200μg/mL范围内呈线性关系,检出限的范围是0.07～1.67μg/mL。5个批次的冬虫夏草菌丝粉保健品中腺嘌呤、尿嘧啶、腺苷、鸟苷、尿苷5组分的定量结果分别在0.15～0.19mg/g、0.72～0.92mg/g、1.44～1.59mg/g、1.51～2.32mg/g和1.77～2.56mg/g范围内,加标回收率的范围是82.83%～109.21%;2个批次的鹿茸血保健品中次黄嘌呤、尿苷的定量结果在36.55～49.97μg/mL和86.08～108.97μg/mL范围内,加标回收率的范围分别是89.68%～96.79%和99.05%～102.81%。     

国内光催化研究进展简述

分1975~1985, 1985~1995和1995~2012三个时期简要介绍了国内光催化研究进展, 主要侧重于光催化材料及其改性、应用和反应机理方面的研究进展, 并指出了当前光催化领域存在的一些重要问题和未来的发展趋势, 涉及到光解水、CO₂还原、环境净化和选择性有机合成等方面.     

青蒿素研究进展

青蒿素是目前治疗疟疾的特效药。本文对自青蒿素发现以来的最新研究进展进行了比较详尽的综述。内容包括: 青蒿素的发现及历史, 青蒿素的来源, 青蒿素的全合成,青蒿素的生物合成, 青蒿素衍生物以及植物组织培养生产青蒿素。     

Interpretation of inorganic arsenic metabolism in humans in the light of observations made in vitro and in vivo in the rat

The toxicity of inorganic trivalent arsenic for living organisms is reduced by in vivo methylation of the element. In man, this biotransformation leads to the synthesis of monomethylarsonic (MMA) and dimethylarsinic (DMA) acids, which are efficiently eliminated in urine along with the unchanged form (As_i). In order to document the methylation process in humans, the kinetics of As_i, MMA and DMA elimination were studied in volunteers given a single dose of one of these three arsenicals or repeated doses of As_i. The arsenic methylation efficiency was also assessed in subjects acutely intoxicated with arsenic trioxide (As₂O₃) and in patients with liver diseases. Several observations in humans can be explained by the properties of the enzymic systems involved in the methylation process which we have characterized in vitro and in vivo in rats as follows: (1) production of As_i metabolites is catalyzed by an enzymic system whose activity is highest in liver cytosol; (2) different enzymic activities, using the same methyl group donor (S-adenosylmethionine), lead to the production of mono- and di-methylated derivatives which are excreted in urine as MMA and DMA; (3) dimethylating activity is highly sensitive to inhibition by excess of inorganic arsenic; (4) reduced glutathione concentration in liver moderates the arsenic methylation process through several mechanisms, e.g. stimulation of the first methylation reaction leading to MMA, facilitation of As_i uptake by hepatocytes, stimulation of the biliary excretion of the element, reduction of pentavalent forms before methylation, and protection of a reducing environment in the cells necessary to maintain the activity of the enzymic systems.     

Recent Advances in Analytical Methodology for in vivo Electrochemistry in Mammals

Electrochemistry is one of the most advanced techniques for monitoring neurochemical activities in the living brain because electrochemical approaches bear the advantageous features of high spatial and temporal resolutions, which facilitate its tremendous potential in investigating the highly spatially heterogeneous brain system and the fast dynamics of neurochemical activities. On the other hand, since brain is the most complicated organ in the sense of its numerous kinds of neurochemical species, high selectivity is always required for any analytical methods that approach the brain. In this review, we will discuss various electrochemical methodologies to achieve selective detection of neurochemicals in mammalian brain and the strategies developed mainly by our group towards selective monitoring of both electrochemically active and inactive neurochemicals. At the end, we will discuss possible solutions towards brain mapping of neurochemical species and combination of neurochemical detection strategy with electrophysiology as the direction of future development of electroanalysis in living brain.     

Use of NAA in marine environment and in archaeology in Greece

Neutron activation analysis (NAA) is a very sensitive and accurate multielement analytical method that is widely applied to the investigation of environmental and archaeological problems. The first part of this paper is a review of pollution studies of toxic trace elements in sediments, seawater and marine organisms of Saronikos Gulf, Greece by NAA. The second part of this paper is a review of provenance studies based on minor and trace element research in ancient ceramics, obsidian, flint, limestone, marble and lead by Instrumental NAA, performed at the NCSR Demokritos.     

Electrolysis in nanochannels for in situ reagent generation in confined geometries

In situ generation of reactive species within confined geometries, such as nanopores or nanochannels is of significant interest in overcoming mass transport limitations in chemical reactivity. Solvent electrolysis is a simple process that can readily be coupled to nanochannels for the electrochemical generation of reactive species, such as H(2). Here the production of hydrogen-rich liquid volumes within nanofluidic structures, without bubble nucleation or nanochannel occlusion, is explored both experimentally and by modeling. Devices comprised of multiple horizontal nanochannels intersecting planar working and quasi-reference electrodes were constructed and used to study the effects of confinement and reduced working volume on the electrochemical reduction of H(2)O to H(2) and OH(-). H(2) production in the nanochannel-embedded electrode reactor output was monitored by fluorescence emission of fluorescein, which exhibits a pH-dependent emission intensity. Initially, the fluorescein solution was buffered to pH 6.0 prior to stepping the potential cathodic of E(0)' for the generation of OH(-) and H(2). Because the electrochemical products are obtained in a 2:1 stoichiometry, local measurements of pH during and after the cathodic potential steps can be converted into H(2) production rates. Independent experimental estimates of the local H(2) concentration were then obtained from the spatiotemporal fluorescence behavior and current measurements, and these were compared with finite element simulations accounting for electrolysis and subsequent convection and diffusion within the confined geometry. Local dissolved H(2) concentrations were correlated to partial pressures through Henry's Law and values as large as 8.3 atm were obtained at the most negative potential steps. The downstream availability of electrolytically produced H(2) in nanochannels is evaluated in terms of its possible use as a downstream reducing reagent. The results obtained here indicate that H(2) can easily reach saturation concentrations at modest overpotentials.     

乙基香兰素研究前景

报导了近几十年来国内外关于乙基香兰素的研究进展与动态,并简单介绍了本文作者在该方面所取得的研究成果,参考文献33篇。     

Reactions in droplets in microfluidic channels

Fundamental and applied research in chemistry and biology benefits from opportunities provided by droplet-based microfluidic systems. These systems enable the miniaturization of reactions by compartmentalizing reactions in droplets of femoliter to microliter volumes. Compartmentalization in droplets provides rapid mixing of reagents, control of the timing of reactions on timescales from milliseconds to months, control of interfacial properties, and the ability to synthesize and transport solid reagents and products. Droplet-based microfluidics can help to enhance and accelerate chemical and biochemical screening, protein crystallization, enzymatic kinetics, and assays. Moreover, the control provided by droplets in microfluidic devices can lead to new scientific methods and insights.     

Conferences in Chemistry Held in 2022

Russian Chemical Bulletin -