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1.
Summary This study determined bromine, iron, scandium and zinc serum levels in Taiwanese aboriginal preschool children living in remote mountainous areas to increase the understanding of the social, cultural, nutrient and ethnic background of the Taiwanese children. Seventy-three serum samples were taken from two ethnic groups of preschool children, Atayal aborigines (AAPC) and Bunun aborigines (BAPC). Sera of these children were freeze dried. Trace elements in sera were identified by instrumental neutron activation analysis (INAA). The accuracy and precision of INAA was evaluated using certified reference materials: Tomato Leaves (NIST-SRM 1570a) and Lichen (IAEA-336). Statistical analysis identified several different patterns for ethnic groups, gender and age via the two-tailed Student's t-test. Analytical results showed that the ranges of Br, Fe, Sc and Zn in sera were somewhat wide. The Zn serum levels (p<0.05) and Br serum levels (p<0.01) in the AAPC were significantly lower than those in the BAPC. However, there were no significant differences in Fe or Sc serum levels between the two groups. Analytical results were compared to published data for different counties. This study is the first investigating trace elements in Taiwanese aborigines and can be used to establish a much-needed serum element database.  相似文献   

2.
Hair samples from junior high school students in metropolitan areas of Taichung, Taiwan were tested for a total of 13 elements, Al, Ag, Br, Cl, Cr, Fe, K, La, Mn, Na, Sc, Se, and Zn by instrumental neutron activation analysis (INAA) to establish seasonal variations, gender and environmental exposures. The seasonal variations of hairs in 39 healthy students (18 males and 21 females; age 13.3 ± 0.4 years; height, 158.0 ± 4.1 cm; weight, 53.4 ± 5.7 kg) were collected at 1.5-month intervals for 1 year starting from late August, 2008. The concentrations of the above elements varied from 103 to 10−2 μg g−1 at different sampling times. A quantified index of agreement (AT) was introduced to help classify the elements. A smaller AT indicated highly consistent quantities of specific metals in the hair while a larger AT indicated increased fluctuation, i.e., less agreement. The different ATs in various hair samples were discussed. The concentrations of these elements are compared with the data in the literature.  相似文献   

3.
Instrumental neutron activation analysis (INAA) and inductively coupled plasma-mass spectrometry (ICP-MS) have been used for the determination of toxic heavy metals and other pollutants in the water of the Das Velhas river in the State of Minas Gerais, in south-east Brazil. Elemental concentrations of about 60 elements were measured in water samples collected to different parts of this river and from two affluents. There was a good agreement between the two analytical methods and the results were complementary. The results indicated an increase in the concentration of several polluting elements in the water from mining industry area.  相似文献   

4.
The formal [2+2] cycloaddition–retroelectrocyclization (CA–RE) reactions between tetracyanoethylene (TCNE) and strained, electron‐rich dibenzo‐fused cyclooctynes were studied. The effect of ring strain on the reaction kinetics was quantified, revealing that the rates of cycloaddition using strained, cyclic alkynes are up to 5500 times greater at 298 K than those of reactions using unstrained alkynes. Cyclobutene reaction intermediates, as well as buta‐1,3‐diene products, were isolated and their structures were studied crystallographically. Isolation of a rare example of a chiral buta‐1,3‐diene that is optically active and configurationally stable at room temperature is reported. Computational studies on the enantiomerization pathway of the buta‐1,3‐diene products showed that the eight‐membered ring inverts via a boat conformer in a ring‐flip mechanism. In agreement with computed values, experimentally measured activation barriers of racemization in these compounds were found to be up to 26 kcal mol?1.  相似文献   

5.
变应性鼻炎与微量元素关系研究   总被引:2,自引:0,他引:2  
为探讨常年性变应性鼻炎患者的免疫功能与体内元素水平变化的关系,检测了PAR患者免疫球蛋白IgE、IgG、IgA、IgM,用原子吸收分光光度法检测了PAR患者血清中Zn、Cu、Fe、Ca、Mg、Mn、Sr的含量,利用统计软件进行相关分析。结果表明,PAR组与对照组相比,Mn、Sr的含量明显下降,IgE升高,且Mg与IgE、IgA呈正相关,Mn与IgE呈正相关。提示PAR患者免疫功能紊乱与血清Mn、Sr的含量有关,Mn、Sr含量降低可能是本病发生的一个内在因素。  相似文献   

6.
为探讨患儿厌食与血微量元素之间的关系,用等离子体原子发射光谱法测定了厌食症患儿与正常对照组血微量元素锌、铁、铜、钙、镁含量。结果表明,厌食症组患儿血清锌明显低于对照组(P〈0.001),而铁与对照组相比差异明显(P〈0.05),而两组血铜、钙、镁比较差异均无统计学意义(P〉0.005)。提示厌食症患儿与血微量元素缺乏密切相关,要重视儿童营养,强调科学、合理的喂养方法和良好的生活习惯。  相似文献   

7.
We measured serum 25 hydroxyvitamin D [25(OH)D] levels of ambulatory adults in tropical Australia to determine whether it is appropriate to continue promoting sun‐safety in this population. In August 2006 (winter), self‐administered questionnaires were completed by 145 Meals‐on‐Wheels volunteers (49.3% male; mean age 57.8 ± 14.7 years; 76.6% response) from Townsville, Queensland (Latitude 19oS). Serum 25(OH)D was analyzed using two common assays. Mean levels were 68.3 (SD ± 18.7; range 26–142) by DiaSorin Radioimmunoassay and 83.0 (SD ± 30.8; range 30–184) by DiaSorin Liaison® one. No participants were 25(OH)D deficient (<25 nmol L−1). Nine participants (6.2%) had 25(OH)D levels between 25 and 50 nmol L−1 (insufficient), by both methods (seven with a BMI ≥ 25). Twenty‐eight participants (19.3%) had one result in the insufficient range and the other in the adequate range. Thus, almost all of these free‐living adults in tropical Australia had adequate vitamin D levels at the end of winter. There was poor agreement between the two 25(OH)D assays. These results suggest it is appropriate to continue promoting sun‐safe messages to the ambulatory Caucasian adult population of North Queensland, which has an extremely high incidence of skin cancer. The lack of agreement between the two assays is a concern. Few doctors are aware of this measurement issue.  相似文献   

8.
Serum levels of fully sialylated C4‐binding protein (FS‐C4BP) are remarkably elevated in patients with epithelial ovarian cancer (EOC) and can be used as a marker to distinguish ovarian clear cell carcinoma from endometrioma. This study aimed to develop a stable, robust and reliable liquid chromatography–hybrid mass spectrometry (UPLC‐MS/MS) based diagnostic method that would generalize FS‐C4BP as a clinical EOC biomarker. Glycopeptides derived from 20 μL of trypsin‐digested serum glycoprotein were analyzed via UPLC equipped with an electrospray ionization time‐of‐flight mass spectrometer. This UPLC‐MS/MS‐based diagnostic method was optimized for FS‐C4BP and validated using sera from 119 patients with EOC and 127 women without cancer. A1958 (C4BP peptide with two fully sialylated biantennary glycans) was selected as a marker of FS‐C4BP because its level in serum was highest among FS‐C4BP family members. Preparation and UPLC‐MS/MS were optimized for A1958, and performance and robustness were significantly improved relative to our previous method. An area under the curve analysis of the FS‐C4BP index receiver operating characteristic curve revealed that the ratio between A1958 and A1813 (C4BP peptide with two partially sialylated biantennary glycans) reached 85%. A combination of the FS‐C4BP index and carbohydrate antigen‐125 levels further enhanced the sensitivity and specificity.  相似文献   

9.
广州市儿童反复呼吸道感染血微量元素分析   总被引:1,自引:0,他引:1  
为了探讨广州地区春夏季期间儿童反复呼吸道感染(RRI)与血微量元素的关系,检测了2004年1~6月份95例儿童反复呼吸道感染(RRI)与正常儿童的血微量元素对照。结果显示,反复呼吸道感染的儿童比正常儿童的血锌明显偏低,血铅明显偏高,有统计学意义;血钙和血镁相差不大,没有统计学意义。提示反复呼吸道感染后的调理需要提高血锌水平和防治铅中毒。  相似文献   

10.
铅暴露对学龄前儿童淋巴细胞免疫表型的影响   总被引:6,自引:0,他引:6  
探讨了低水平铅暴露对学龄前儿童淋巴细胞免疫表型的影响。用石墨炉原子吸收光谱法对 2 1 7名学龄前儿童进行血铅浓度筛查 ,并在此基础上用流式细胞仪检测不同血铅水平对学龄前儿童淋巴细胞免疫表型CD+ 3 、CD+ 3 CD+ 4 、CD+ 3 CD+ 8、CD- 3 CD+ 19、CD- 3 CD+ 56的影响。结果表明 ,高铅组 (血铅≥ 0 4 83μmol/L的学龄前儿童CD+ 3 CD+ 4 、CD+ 3 CD+ 4 /CD- 3 CD+ 8水平与低铅组 (血铅 <0 4 83μmol/L)比较显著下降 (P <0 0 1 ) ;而CD+ 3 CD+ 8细胞显著升高 (P <0 0 5 ) ;CD+ 3 、CD- 3 CD+ 19、CD- 3 CD+ 56细胞无显著差异 (P <0 0 5 )。低水平铅暴露对学龄前儿童淋巴细胞免疫表型具有不利影响  相似文献   

11.
Screening assays capable of performing quantitative analysis on hundreds of compounds per week are used to measure metabolic stability during early drug discovery. Modern orthogonal acceleration time‐of‐flight (OATOF) mass spectrometers equipped with analogue‐to‐digital signal capture (ADC) now offer performance levels suitable for many applications normally supported by triple quadruple instruments operated in multiple reaction monitoring (MRM) mode. Herein the merits of MRM and OATOF with ADC detection are compared for more than 1000 compounds screened in rat and/or cryopreserved human hepatocytes over a period of 3 months. Statistical comparison of a structurally diverse subset indicated good agreement for the two detection methods. The overall success rate was higher using OATOF detection and data acquisition time was reduced by around 20%. Targeted metabolites of diazepam were detected in samples from a CLint determination performed at 1 µM. Data acquisition by positive and negative ion mode switching can be achieved on high‐performance liquid chromatography (HPLC) peak widths as narrow as 0.2 min (at base), thus enabling a more comprehensive first pass analysis with fast HPLC gradients. Unfortunately, most existing OATOF instruments lack the software tools necessary to rapidly convert the huge amounts of raw data into quantified results. Software with functionality similar to open access triple quadrupole systems is needed for OATOF to truly compete in a high‐throughput screening environment. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

12.
Concentration levels of eight trace elements in 120 samples of human blood serum were investigated by Instrumental Neutron Activation Analysis (INAA) for the purpose of medical research. The elements Co, Cr, Cs, Fe, Rb, Sc, Se, and Zn were simultaneously determined by the relative method in comparison with inorganic standards treated under identical conditions. The process of analysis and its reliability was checked using human serum and IAEA certified reference material. Statistical results are expressed in ppm or ppb. Both normal and, if necessary, log-normal frequency distributions of all elements determined are presented, types of distribution curves are verified statistically on 95% level of probability.  相似文献   

13.
选取原发性肾病综合征(PNS)患儿96例作为研究组,选取同期96例健康体检儿童作为对照组,开展前瞻性队列研究,均行超声颈动脉参数、血清可溶性髓系细胞表达的触发受体-1(sTREM-1)、可溶性尿激酶型纤溶酶原激活物受体(suPAR)水平检测,并进行对比分析。本研究发现,研究组患儿颈动脉内中膜厚度(cIMT)、平均管壁横截面积(WCSA)、血清sTREM-1和suPAR水平高于对照组,血管壁运动度(△D)低于对照组(P<0.05);PNS患儿TG、TC、尿NAG、β2-MG、24 h Upro与cIMT、WCSA、血清sTREM-1、suPAR水平间存在正相关关系,与△D间存在负相关关系(P<0.05);随着cIMT、WCSA、血清sTREM-1、suPAR水平升高及△D降低,PNS发病风险逐渐增加(P<0.05);cIMT、△D、WCSA、血清sTREM-1、suPAR联合预测PNS患儿急性肾损伤的曲线下面积(AUC)为0.914。据此可得PNS患儿超声颈动脉参数中cIMT、WCSA及血清sTREM-1、suPAR表达水平明显升高,△D异常降低,且均与患儿血脂升高、肾功能降低存在明显相关性,可辅助临床预测PNS患儿急性肾损伤风险。  相似文献   

14.
Hepatocarcinoma (HCC) has a very high mortality rate and the high recurrence and metastasis rates contribute to the poor prognosis of HCC patients. To understand HCC formation and metastasis, we assessed the metabonomics of rat HCC and HCC with lung metastasis (HLM). The HLM rat model was established by exposure to diethylnitrosamine (DEN). Levels of serum and urine metabolites were quantified with gas chromatography/time‐of‐flight mass spectrometry (GC/TOFMS), and data were analyzed with partial least‐squares discrimination analysis (PLS‐DA). Serum and urine levels of some metabolites differed significantly between the control, HCC, and HLM groups. The products and intermediates from glycolysis and glutamate metabolism were elevated, while the tricarboxylic acid (TCA) cycle was inhibited, in both HCC and HLM. HLM samples revealed enhanced metabolism of nucleic acids, amino acids and glucuronic acid. PLS‐DA indicated that principal component weighting was greatest for serum serine, phenylalanine, lactic acid, tyrosine and glucuronic acid, and urine glycine, serine, 5‐oxyproline, malate, hippuric acid and uric acid. These data provide novel information that will improve understanding of the pathophysiological processes involved in HCC and HLM, and revealed potential metabolic markers for HCC invasion and metastasis. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

15.
探讨小儿癫痫与血清锌、铜的关系.结果表明:癫痫患儿与正常儿童比较,血清锌无显著性差异.血清铜有非常显著性差异癫痫类型中大发作及癫痫并智力低下儿童,缺锌明显.与正常儿童比较有显著性差异.提示治疗癫痫大发作及并智力低下患儿,在抗癫痫治疗同时,补充含锌制剂.  相似文献   

16.
A high‐throughput LC–MS/MS bioanalytical method was developed and validated for the determination of hydrocortisone in mouse serum via supported liquid extraction (SLE) in a 96‐well plate format. Although sample extracts from SLE result in similar matrix effects compared with conventional liquid–liquid extraction (LLE), greater analyte extraction recovery and much higher analysis throughput for the quantitative analysis of hydrocortisone in mouse serum were obtained. The current LC‐MS/MS method was validated for a concentration range of 2.00–2000 ng/mL for hydrocortisone using a 0.100 mL volume of mouse serum. The intra‐ and inter‐day precision and accuracy of the quality control samples at low, medium and high concentration levels showed ≤12.9% CV and ?3.4–6.2% bias for the analyte in mouse serum. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

17.
Two supramolecular complexes [Zn(tacd)2](C6H8O4)·6H2O(1) and [Cu(tacd)2]Cl2·4H2O(2) were synthesized and characterized by elemental analysis, IR spectra, TGA and single-crystal X-ray diffraction analysis. The crystal structure showed that the metal ions in complexes 1 and 2 had similar coordination circumstance. But for the complex 2, it formed a novel two-dimensional supramolecular network with 12-membered rings and four-membered rings via hydrogen bond interaction. The thermal gravimetric analyses indicated that the two complexes had similar steps of weight-loss. On the basis of experiment, the two complexes were calculated by DFT-B3LYP/6-31G(d) in Gaussian 03. The results of calculation are in good agreement with the experiment.  相似文献   

18.
A liquid chromatography electrospray ionization tandem mass spectrometry (LC‐MS/MS) method has been developed for the determination of 5,10‐methylenetetrahydrofolate (methyleneTHF), tetrahydrofolate (THF) and 5‐methyltetrahydrofolate (methylTHF) in colorectal mucosa and tumor tissues. The folate extraction method includes homogenization, heat and folate conjugase treatment to hydrolyze polyglutamyl folate to monoglutamyl folate. Before analysis on LC‐MS/MS, simple and fast sample purification with ultrafiltration (molecular weight cut‐off membrane, 10 kDa) was performed. Folates were detected and quantified using positive electrospray. The method described in the present paper was successfully applied to determine the level of three folate monoglutamates in mucosa and tumor samples from 77 colorectal cancer patients, starting from a limited amount of tissue. The results showed that the LC‐MS/MS method has a great advantage over other previously used methods because of its high sensitivity and selectivity. Significantly higher levels of methyleneTHF and THF were found in tumor compared with matched mucosa tissues. Folate levels in adjacent mucosa were associated with tumor location, age and gender. The correlation between folate levels and tumor site further strengthens the fact that development of right‐ and left‐sided tumors follows different pathways. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

19.
Serum for reference pools of in vivo polychlorinated biphenyls (PCBs) was obtained from four goats that had received one dose (100 mg kg-1) of a selected technical Aroclor (AR) (1016, 1242, 1254 or 1260) and were allowed to recover for 30 d. These pools were used to assess the differences in an analytical method that determines and quantifies PCBs using packed-column gas chromatography (PCGC) (quantified on the basis of mean mass percent. data for grouped PCB peaks) and capillary-column gas chromatography (CCGC) (quantified on the basis of percent. composition data for specific congeners). With CCGC, results were statistically significantly different (p less than or equal to 0.0002) from results with PCGC for ARs 1016, 1242 and 1254 but not for AR 1260 (p = 0.23). When comparing these gas chromatographic methods using bovine serum spiked in vitro with the same ARs at 17-25 p.p.b., it was found that the methods were not statistically significantly different for any of the ARs (p = 0.30-0.92). Levels of serum PCB determined by the two methods for 12 persons, divided into two groups according to exposure, were compared using the paired t-test. Group 1 consisted of three persons with dietary and/or environmental exposure; one with dietary and/or environmental exposure in addition to occupational exposure dating back 20 years. Group 2 consisted of eight persons with recent occupational exposure.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

20.
Little is known about melamine (MEL) analysis in children's urine. In this study, an isotopic ultra‐performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) method was developed and systematically validated for the analysis of MEL in urine. The method is easily performed and comprises acidification, solid‐phase extraction (SPE) and UPLC/MS/MS analysis. 13C3N3(15NH2)3 was used as the internal standard (IS) for calibration. Transition ions m/z 127 > 85 of MEL and m/z 133 > 89 of the IS were used for quantification and m/z 127 > 68 of MEL was used for quantitative confirmation. Recovery and precision were assessed to guarantee the applicability of the method. The limit of quantification (LOQ) was 0.01 µg/mL while the calculated method detection limit was 0.006 µg/mL. The mean recoveries ranged from 96–99%. The method was then applied to analyze urine samples from children who had potentially consumed MEL‐tainted dairy products during screening in Taiwan. Ten nephrolithiasis cases and 20 age‐ and gender‐matched controls were selected for this study. Three out of the 10 nephrolithiasis cases had elevated levels of MEL. Comparatively, twenty age‐ and gender‐matched non‐nephrolithiasis controls consuming Taiwan brand milk powder all showed MEL levels lower than the detection limit except for two children with background levels of 0.02 µg/mL. The background level in these children urine samples was established by UPLC/MS/MS analysis. Positive results of urine MEL tests might be associated with nephrolithiasis in these candidates. Measurement of urine MEL concentration can be helpful in confirming MEL‐related nephrolithiasis, but its clinical application needs further clarification. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

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