聚丙烯酰胺双向凝胶电泳法分析变色人发角蛋白组成

报道了一种用双向聚丙烯酰胺凝胶电泳分析经Ｓ－羧甲基化修饰的变色人发角蛋白样品的方法，以含８ｍｏ１／Ｌ脲变性凝胶电泳做第一向，ＳＤＳ－ＰＡＧＥ做第二向。不同处理的变色人发得到有差别的双向电泳图谱，即不同处理方法得到的人发蛋白质组成有差异。以此可做为人发变色处理的一个定性方法。     

Isolation of strontium pools and isotope ratios in modern human hair

The elements of human hair record specific information about an individual's health, diet, and surrounding environment. Strontium isotope ratios of human hair have attracted interest as they potentially record an individual's environment. Yet, separating the external environmental signals from the internal dietary indicators has remained a challenge. Here, we examined the effects of five different hair-cleaning methodologies to determine the extent that internal and external strontium signals can be isolated from human hair. In the first study of its kind, we employed an in-line strontium purification methodology and a multi-collector inductively coupled plasma mass spectrometer to obtain high-precision strontium isotope ratio of human hair and of leachates of the different washing treatments. We found that the different applications of an individual treatment removed a consistent amount of strontium from hair and that replicate analyses showed each treatment altered the strontium isotope ratios of hair consistently. A mass-balance approach was applied to demonstrate that strontium was quantitatively removed and was accounted for in either the treated hair or the leachate. We observed that strontium isotope ratio varied as a function of treatment aggressiveness so as to suggest that there was a fine-scale structuring of strontium within hair (transverse cross-sectional variations); these variations existed as differences in strontium concentrations and isotope ratios. As a result, the Sr isotope ratio of hair and hair leachates treated with the most aggressive cleaning methods reflected the isotope ratios of the interior and total exterior strontium signatures, respectively. The results of this study indicate that external environmental strontium signals can be distinguished from the internal signals and therefore permit the application of strontium isotope ratios of modern human hair for geospatial applications.     

Improved STR typing of telogen hair root and hair shaft DNA

Today the STR typing of telogen hair and hair shafts is regarded as a challenge. The small DNA quantity in the hair is highly degraded. Another problem are PCR inhibitors in the hair. In particular hair pigments, the melanins, are known to inhibit PCR. Hairs are exposed to sunlight and partly to chemical oxidation processes, which make them even more difficult to analyze. To increase the chances of a correct typing of hair, the small amount of DNA must be successfully isolated and the inhibitors have to be removed or neutralized. Furthermore, miniSTR typing improves the analysis of stains with degraded DNA like it is the case with hair. We introduce a nonorganic extraction method and in addition a miniSTR concept which is promising in typing stains with little and degraded DNA, especially hairs. The miniSTR concept including five database STRs (SE33, VWA, TH01, FGA, D3S1358) and the gender typing system Amelogenin was optimized for the amplification of hair DNA. Compared to commercial STR kits, this approach resulted in considerably higher success rates.     

A rapid nuclear staining test using cationic dyes contributes to efficient STR analysis of telogen hair roots

Telogen hairs presented in the crime scene are commonly encountered as trace evidence. However, short tandem repeat (STR) profiling of the hairs currently have low and limited use due to poor success rate. To increase the success rate of STR profiling of telogen hairs, we developed a rapid and cost‐effective method to estimate the number of nuclei in the hair roots. Five cationic dyes, Methyl green (MG), Harris hematoxylin (HH), Methylene blue (MB), Toluidine blue (TB), and Safranin O (SO) were evaluated in this study. We conducted a screening test based on microscopy and the percentage of loss with nuclear DNA, in order to select the best dye. MG was selected based on its specific nuclei staining and low adverse effect on the hair‐associated nuclear DNA. We examined 330 scalp and 100 pubic telogen hairs with MG. Stained hairs were classified into five groups and analyzed by STR. The fast staining method revealed 70% (head hair) and 33.4% (pubic hair) of full (30 alleles) and high partial (18–29 alleles) STR profiling proportion from the lowest nuclei count group (one to ten nuclei). The results of this study demonstrated a rapid, specific, nondestructive, and high yield DNA profiling method applicable for screening telogen hairs.     

Studies of human hair by friction force microscopy with the hair-model-probe

We employed a cantilever modified with a self-assembled monolayer (SAM) as a “hair-model-probe” for friction force microscopy (FFM) to measure friction acting between hair and hair-like surfaces. The “hair-model-probe” was prepared by forming a SAM of octadecanethiol on a gold-coated cantilever. We investigated frictional properties of human hair at both root and tip, and the dependency on applied load, influence of scanning direction, and local frictional distribution. The friction coefficient of the hair tip was greater than that of the hair root. Load dependency of friction at the hair tip was clearly observed, while friction at the hair root was less dependent on applied load. At the hair root, an anisotropic frictional property was observed: friction force along the long axis of the hair fiber was about 1.5–2 times larger than that along the short axis. Atomic force microscopy (AFM) images showed striations on the cuticle cells that have about 6 nm depth and their long axis oriented in the direction of the hair fiber. The frictional distribution images revealed that the local areas showing strong shear corresponded to striations. Since such distribution of friction was not observed at the hair tip, it is suggested that the anisotropic frictional property at the hair root was caused mainly by the striations. The frictional distribution in regions that excluded the striations also showed the anisotropic frictional property that friction parallel to the long axis of the hair fiber is greater than that along the short axis. This result suggests that the orientation of fatty acid molecules comprising the fat layer (F-layer) may also contribute to the anisotropic frictional property. We have concluded that loss of the F-layer is a dominant cause of strong friction detected at the hair tip, and at the striations of the hair root.     

孕期和哺乳期铁缺乏对新生豚鼠耳蜗毛细胞的影响

为观察孕期和哺乳期铁缺乏对新生豚鼠听功能及耳蜗毛细胞形态结构的影响,将18只怀孕豚鼠按体质量随机分为3组,每组6只,分别是重度铁缺乏组、中度铁缺乏组和对照组;在仔鼠出生后第9天断乳,乙醚麻醉,畸变产物耳声发射( DPOAE)检测听力状况;分离耳蜗,行全基底膜铺片,用TRITC标记的鬼笔环肽染色,观察耳蜗毛细胞.结果表明...     

Connarus semidecandrus Jack Exerts Anti-Alopecia Effects by Targeting 5α-Reductase Activity and an Intrinsic Apoptotic Pathway

There is a growing demand for hair loss treatments with minimal side effects and recurrence potential. Connarus semidecandrus Jack has been used as a folk medicine for fever in tropical regions, but its anti-alopecia effects remain unclear. In this study, the anti-androgenic alopecia effect of an ethanol extract of Connarus semidecandrus Jack (Cs-EE) was demonstrated in a testosterone-induced androgenic alopecia (AGA) model, in terms of the hair–skin ratio, hair type frequency, and hair thickness. The area of restored hair growth and thickened hair population after Cs-EE treatment showed the hair-growth-promoting effect of Cs-EE. Histological data support the possibility that Cs-EE could reduce hair loss and upregulate hair proliferation in mouse skin by shifting hair follicles from the catagen phase to the anagen phase. Western blotting indicated that Cs-EE reduced the expression of the androgenic receptor. Cs-EE treatment also inhibited programmed cell death by upregulating Bcl-2 expression at the mRNA and protein levels. The anti-alopecia effect of Cs-EE was confirmed by in vitro experiments showing that Cs-EE had suppressive effects on 5-α reductase activity and lymph node carcinoma of the prostate proliferation, and a proliferative effect on human hair-follicle dermal papilla (HDP) cells. Apoptotic pathways in HDP cells were downregulated by Cs-EE treatment. Thus, Cs-EE could be a potential treatment for AGA.     

MALDI-TOF and MALDI-FTICR imaging mass spectrometry of methamphetamine incorporated into hair

A new approach is described for imaging mass spectrometry (IMS) of methamphetamine (MA) incorporated into human hair using matrix-assisted laser desorption/ionization (MALDI)-time-of-flight (TOF) and MALDI-Fourier transform ion cyclotron resonance (FTICR). A longitudinal section of a lengthwise manually-cut single human hair shaft from a chronic MA user was directly analyzed by MALDI-TOF-IMS after deposited with α-Cyano-4-hydroxycinnamic acid matrix. A barcode-like image, which was most probably generated with repeated intakes of MA, was for the first time obtained by monitoring MA-specific product ion in the selected reaction monitoring mode. Laser beam scan lengthwise-cut hair shafts gave only poor mass spectra of MA, probably due to the loss of MA and/or the thermal denaturation of hair. The identity of MA detected in hair was further confirmed by MALDI-FTICR mass spectrometry. A combination with ultra-high resolution mass spectrometry by FTICR provided indisputable identification of MA. The MALDI-FTICR-IMS of another hair shaft from the same MA user also provided a barcode-like image by monitoring the protonated molecule of MA with ultra-high resolution. The two barcode-like images exhibited a close resemblance. Thus, MALDI-IMS can offer a new perspective: 'imaging hair analyses for drugs'.     

多补钙对儿童发钙及生长发育的作用

为研究多补钙对儿童体内钙含量的影响和对生长发育的促进作用,给202名6个月至7岁的儿童服用多补钙1年,在服用前后测量体重、身高、坐高、头围、胸围、臂围和发钙,对儿童形态指标先做等级评价后,应用配对设计差值的符号秩和检验(Wilcoxon配对法)进行统计分析,发钙采用配对设计差值t检验分析。结果表明,服用多补钙1年后儿童发钙平均增加113×10-6,身高、坐高、头围、胸围和臂围的发育水平有显著提高。提示多补钙能有效地提高儿童发钙含量,对儿童的生长发育有明显促进作用。     

Hair analysis of nicotine and cotinine for evaluating tobacco smoke exposure by liquid chromatography-mass spectrometry

A simple liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) method for the determination of nicotine and cotinine in human hair was established. In the procedure, a hair sample (10 mg) was washed with dichloromethane and digested in 2.5 M sodium hydroxide. The digest was extracted with dichloromethane and then 25 mM hydrochloric acid in methanol was added to the extract, to prevent loss of analytes. The solution was evaporated and redissolved in the mobile phase, methanol/10 mM ammonium acetate (30/70, v/v). A 20 microL aliquot of redissolved solution was subjected to analysis. Nicotine and cotinine in human hair were quantified by using deuterated analytes as internal standards. The quantification limits were 8 microg/L for nicotine and 0.9 microg/L for cotinine. The proposed method was applied to measure the concentrations of nicotine and cotinine in hair of smokers and non-smokers to evaluate their self-reported smoking and exposure to environmental tobacco smoke. In both cases, the method provided good selectivity, accuracy and precision.     

Effects of flavonoid derivatives on human microvascular endothelial cells

Some natural compounds, including flavonoids, are active in vasculature re-growth during hair follicle disruption, but their effects have not been yet evaluated directly on microvascular endothelial cells. Skin vascularisation regulates the physiological blood supply required for hair growth and its dysregulation is the basis of several human diseases. Follicle-derived vascular endothelial growth factor (VEGF) release from follicular keratinocytes promotes perifollicular vascularisation and increases follicle and hair size, while blockade of VEGF-mediated angiogenesis leads to impaired hair growth. Here, we tested three flavonoids, namely visnadin (VSD), hesperidin (HSP) and baicalin (BC), on cultured human microvascular endothelial cells (HMEC), comparing their effects with minoxidil (MXD), a synthetic drug broadly used in the treatment of androgenetic alopecia. The response to these compounds was assayed in terms of endothelial survival, proliferation, tubulogenesis and proangiogenic signalling. We show that BC promotes HMEC proliferation, while both VSD and MXD enhance tubulogenesis. Interestingly, only HSP increases VEGFR-2 phosphorylation.     

超高效液相色谱-四极杆-飞行时间质谱法测定防脱发化妆品中19种非法添加化学成分

建立了超高效液相色谱-四极杆-飞行时间质谱(UPLC-Q-TOF-MS)法,结合高分辨质谱数据库,用于快速筛查及定量分析防脱发化妆品中19种非法添加化学成分.实验比较了提取溶剂的影响,优化了色谱条件和质谱条件.采用ACQUITY UPLC BEH C18色谱柱(100 mm×2.1 mm,1.7μm)进行色谱分离,以乙...     

某铅锌矿区儿童发铅水平及对健康影响的调查

为了解某铅锌矿区铅对儿童的危害情况,探讨铅污染对儿童智商及生长发育的影响,选择某铅锌矿区某冶炼厂区居住5年以上,年龄在6～10岁的儿童186名作为观察组,同时选择居住在距矿区40 km以外、年龄在6～10岁的儿童156名作为对照组,进行了儿童一般状况的体格检查(包括:缺钙、脱发、贫血、易患感冒)、智商测定(包括:语言智...     

Hair analysis as a new tool to monitor adherence to long-term therapy to statins

Statins are cholesterol-lowering medications which are widely prescribed as first-line treatment for hyperlipidemia, against high blood cholesterol aimed at reducing the risk of atherosclerotic diseases. Notwithstanding their undoubted efficacy, the needed long-term treatment with these drugs is characterized by a high percentage of dropout. Consequently, an effective tool to verify the patients’ compliance to statin therapy is needed. In this context, the analysis for drugs and drug metabolites in the hair may represent an almost ideal tool because, according to a sound body of forensic toxicological literature, concentrations in the hair matrix reflect the chronic intake of drugs and pharmaceuticals. In this light, in the present study, a novel, specific and sensitive ultra-performance liquid chromatography–tandem mass spectrometry method has been developed to determine six statins and their metabolites (namely atorvastatin, (p)α-OH-atorvastatin-lactone, (o)α-OH-atorvastatin-lactone, rosuvastatin, N-desmethyl rosuvastatin and pravastatin) in human hair. After optimization, the method was successfully validated in terms of selectivity, linearity, sensitivity, precision, accuracy, stability and matrix effect. Moreover, the practical applicability of this method for verifying adherence to statin therapy was assessed by testing samples of hair collected from subjects under long-term therapy with statins.     

Effect of sample pre-treatment on the determination of steroid esters in hair of bovine calves

The effect of three sample pre-treatment steps, washing, cutting and grinding on the determination of steroid esters in hair is studied. The study is performed by using hair samples obtained after pour-on application of steroid esters to bovine calves. After sample pre-treatment the hair is treated with a mild reducing agent [tris(2-carboxyethyl)phosphine hydrochloride] to extract the steroid esters. After a solid-phase extraction clean-up step the extracts are analysed by using liquid chromatography combined with triple–quadrupole mass spectrometric detection. For the washing step the use of non-organic washing solvents like (warm) water and a solution of 0.1% sodium dodecyl phosphate and organic solutions containing different percentages of methanol are tested. By using the non-organic solvents and the organic solvents with a percentage of methanol <20% the recovery results are as good as the results obtained without washing the hair. Cutting the hair samples increases the analyte recoveries of incurred steroid esters by 20% compared to the non-cut hair. The analyte recoveries of cut hair samples are about 60–80% that of ground hair samples. The obtained surface expansion of hair samples by grinding proves to be necessary in order to achieve the highest possible analyte yields. Finally the use of pressurised liquid extraction (PLE) for the extraction of steroid esters from plain (no washing, cutting or grinding) hair is investigated. The first results show lower (up to 40%) extraction recoveries in comparison with the classical solvent extraction procedures. If the limit of detection requirement is met, PLE may be an alternative for extracting large numbers of hair samples due to the short sample treatment procedure involved.     

发铅与血铅的相关关系

头发中的铅除直接来源于血液外,体内和环境中的铅还通过纵向和横向多种通道渗入到头发结构中,头发和血液的铅动力学行为也不相同。发铅和血铅之间存在复杂的相关关系,铅摄入量的重大变化可削弱两者的关联强度,高铅暴露则加强两者的关联强度。骨铅的动员和释放,以及发样采集或预处理不当,均可使血铅或发铅值偏离真实,导致两者关联的不确定。血铅是近期铅暴露的量度指标,发铅可给出从前铅暴露或铅负荷的信息,后者更适合于人群铅中毒筛查或监测。     

A fast screening MALDI method for the detection of cocaine and its metabolites in hair

Matrix-assisted laser desorption/ionisation (MALDI) mass spectrometry was used for the rapid detection of cocaine, benzoylecgonine and cocaethylene in hair. Different MALDI sample preparation procedures have been tested and the employment of a multi-layer 'graphite-sample-electrosprayed alpha-cyano-4-hydroxycinnamic acid (HCCA)' yielded the best results for standard solutions of the target analytes. The same approach was subsequently applied to hair samples that were known to contain cocaine, benzoylecgonine and cocaethylene, as determined by a classical GC-MS method. It was however necessary to extract hair samples by incubating them in methanol/trifluoroacetic acid for a short time (15 min) at 45 degrees C; 1 microl of the obtained supernatant was deposed on a metal surface treated with graphite, and HCCA was electrosprayed on it. This procedure successfully suppressed matrix peaks and was effective in detecting all the target analytes as their protonated species. The results obtained give further confirmation of the effectiveness of the MALDI for detecting drugs and their metabolites in complex biological matrices. The method can be useful as a fast screening procedure to detect the presence of cocaine and metabolites in hair samples.     

826例儿童发铅、锌、铜、铁、钙含量分析

探讨了东乡县儿童体内微量元素情况。对826例儿童发铅、锌、铜、铁、钙检测结果分各年龄组进行了分析。结果表明,826例儿童中发铅含量超标512例,占61．99％;发锌含量低标604例,占73．1％;发铜含量低标46例,占5．6％;发铁含量低标95例,占11．5％;发钙含量低标116例,占19．6％,占19．6％。5种元素含量与年龄有关,随着年龄增大,发铅、锌、铜、钙含量下降,发铁含量上升。分析表明,儿童铅污染、锌、钙缺乏程度相当普遍且严重。在儿童生长发育期进行常规的微量元素检测非常必要。     

绿色安全染发剂的研究进展及展望

染发已成为人们的日常需要与时尚选择。目前广泛使用的化学染发剂主要成分为对苯二胺类物质,其引起的致敏性、致癌性与致突变性等问题日益凸显。生物质染发剂及仿生染发剂与化学合成染发剂相比具有安全低毒、资源可再生、环境友好等优点。本文以近年来国内外对绿色安全染发剂的研究为基础,从头发的组成结构和显色机理出发,从生物质染发剂以及仿生染发剂两个方面总结了绿色安全染发剂的研究现状与发展瓶颈,并对其应用前景进行了展望,旨在为安全无毒、绿色健康染发剂的研发提供参考。     

高效液相色谱法同时测定氧化型染发产品中33种染发剂

建立了高效液相色谱同时测定氧化型染发产品中33种禁限用染发剂含量的分析方法。采用Waters Atlantis^® T3 MV Kit色谱柱（250 mm×4.6 mm，5 μm），以磷酸盐缓冲液-乙腈为流动相，梯度洗脱，流速为1.0 mL/min，柱温为25℃；采用二极管阵列检测器（DAD），检测波长为235及280 nm，进样量为5 μL。结果表明，各成分在线性范围内线性关系良好，相关系数均高于0.999，各成分精密度实验相对标准偏差（RSDs）均小于2%；四氨基嘧啶硫酸盐和2，4-二氨基苯氧基乙醇盐酸盐在12 h内稳定性实验RSDs小于5%，其余31种成分在24 h内稳定性实验RSDs均小于5%；各成分在3个浓度水平下的加标回收率为77.6%~116.3%。该方法简便、快速、准确，适用于氧化型染发产品中多种染发剂的检测。