在一个中国人家庭中发现联锁的三个α-珠蛋白基因

本文以重组质粒pRB_α1 PstI-1.5Kb片段为α-珠蛋白基因探针,应用限制性内切酶图谱和印迹杂交技术,分析了一个中国人家庭的α-珠蛋白基因在染色体上的排列。该家庭的父母在临床上均无明显的贫血症状,而其一对孪生女患有HbH病。基因分析表明,母亲在一条染色体上具有三个紧密连锁的α-基因,而在另一染色体上完金缺失α-基因(ααα/--),父亲为右侧缺失α-地贫2杂合子(α-/αα),两个女儿均为右侧缺失α-地贫2与α-地贫1双重杂合子(α-/--)。     

气相色谱法测定鳗鱼中残留的硫丹

建立了气相色谱检测鳗鱼中残留的硫丹（包括α-硫丹和β-硫丹）的方法。鳗鱼样品经过提取、净化,采用气相色谱-电子捕获检测法进行硫丹含量的测定。α-硫丹和β-硫丹的检测低限均为1 μg/kg;α-硫丹和β-硫丹在2～50 μg/kg范围内其含量与峰面积呈现良好的线性关系,相关系数均为0.999;α-硫丹和β-硫丹在添加水平为1.0,2.0,5.0 μg/kg时,回收率分别为74%～89%和89%~98%,相对标准偏差为3.7%~7.2%和4.7%~8.7%。表明方法的重现性和准确性都非常好。     

地中海贫血基因诊断在优生优育中的应用情况分析

目的探讨地中海贫血基因诊断对优生优育的应用指导作用。方法回顾性统计分析广州市番禺区何贤纪念医院2011年1月至2014年12月期间的5 086例产检孕妇中109例疑似地中海贫血患者基因诊断筛查结果。结果 5 086例产检孕妇中74例确诊为地中海贫血,占1.45%,其中α地中海贫血患者32例,占0.63%,以αα/--SEA最为常见,占65.63%;β地中海贫血患者42例,占0.82%,以CD17(A→T)最为常见,占38.10%。结论本地区常见地中海贫血基因突变类型的筛查有利于指导产前诊断,减少Hb Bart'水肿综合症和Hb H病患儿的出生,从而实现优生优育。     

基于LTQ-Orbitrap液相色谱-质谱联用技术的乳源乳清蛋白组分的差异性研究

利用LTQ Orbitrap XL组合型傅立叶变换高分辨质谱系统分析了乳源蛋白主要组分肽指纹图谱。对南方水牛乳与不同来源的乳清蛋白的氨基酸序列研究结果表明,乳清蛋白经酶解后主要为α-乳白蛋白(α-La)和β-乳球蛋白(β-Lg)组分,乳清蛋白肽质指纹谱的分析显示水牛乳与荷斯坦奶乳清蛋白α-La氨基酸发生变异的比率明显少于山羊奶乳清蛋白α-La,说明荷斯坦奶α-La和水牛乳α-La的差异更小,同源性更强;而水牛乳β-Lg与荷斯坦乳β-Lg氨基酸发生变异的部位比率要多于山羊奶,水牛乳β-Lg与山羊奶同源性更强;乳源酪蛋白酶解后的肽段主要组分为αs1-CN,β-CN,κ-N,通过对水牛乳酪蛋白的氨基酸序列的差异性分析,不同品种的乳源酪蛋白的氨基酸序列明显存在差异。与乳清蛋白相比,奶牛品种差异导致乳蛋白发生氨基酸差异现象更显著,酪蛋白的氨基酸序列对比表明,水牛奶酪蛋白与山羊奶酪蛋白比与乳牛酪蛋白的差异更大。     

六氢吡啶存在下β-环糊精诱导α-溴代萘室温磷光分析

微量六氢吡啶(HHP)存在下,由于三元包络物α-溴代萘(-αB rN)/β-环糊精(-βCD)/HHP的形成,不经除氧就可观察到强而稳定的室温磷光(RTP)发射。详细研究了温度、pH值以及形成包络物的3种组分物质的浓度的变化对体系RTP的影响。在优化实验条件下,体系的RTP强度与-αB rN的浓度在2.0~20.0μmol/L范围内呈良好线性关系,α-B rN的检出限3.7×10-8mol/L。将所建方法用于合成样品中-αB rN的测定,实验结果表明该方法的加标回收率为92.4%;相对标准偏差小于1.57%(n=7)。     

共振瑞利散射光谱法同时测定α-萘酚和β-萘酚异构体

在硼砂-HCI(pH=8.2)的水溶液中,α-萘酚(α-N)和β萘酚(β-N)分别与卢一环糊精(β-CD)形成包合物,对共振瑞利散射光谱(RRS)有很强的增敏作用.实验发现.α-N和β-N两种包合物的RRS光谱在320hm处有等强度的等散射点,β-N的包合物在338nm处出现一个突出尖峰,经偏振实验证实是共振荧光峰,而两者在470nm处的共振瑞利散射峰形和增强趋势一致,且具加和性.故可在470nm处测定萘酚的总量,再在338nm处以"同原射线计量法"测定β-N和α-N的含量.在470nm处测定萘酚总量实验的线性范围为5.0×10-63.6×10-4mol/L,最低检出限为2.0×10-6mol/L,RSD为3.5%.在338nm处测定β-N和α-N含量的线性范围均为5.0×10-6～3.1 X 10-4mol/L,最低检出限分别为1.6×10-6mol/L和1.8×10-6mol/L.RSD分别为3.7%和3.6%.测定的选择性较好,据此可对合成样品进行同时测定和对α-萘酚试剂的纯度分析,结果令人满意.     

亲水交互作用-反相二维液相色谱-串联质谱同时测定乳制品中20种抗生素残留

建立了亲水作用-反相二维液相色谱-串联质谱测定乳制品中β-内酰胺、四环素、大环内酯、氨基糖苷、酰胺醇、喹诺酮和磺胺7类20种抗生素残留的方法.样品与C18和CN填料混合,进行基质固相分散萃取,以乙腈和水洗脱,洗脱液旋转蒸发至近干,残渣流动相溶解后分析.对样品前处理条件、色谱流动相、质谱参数进行了优化.各分析物回归方程的相关系数为0.9945 ～0.9998;以定量离子信噪比为3和10时所对应的样品中分析物浓度计算检出限和定量限,分别为0.10 ～ 2.40 μg/kg和0.33 ～ 7.92 μg/kg.奶粉和牛奶中添加水平25 μg/kg的加标回收率分别为72.5％ ～ 97.2％和70.1％ ～96.8％,相对标准偏差为4.2％ ～8.8％和3.7％ ～9.9％.本方法应用于实际样品测定,结果满意.     

光谱学结合分子动力学研究秋水仙碱与血红蛋白之间相互作用机制

本文通过分子光谱、分子对接以及分子动力学模拟等技术手段探究了秋水仙碱与血红蛋白(Hb)之间相互作用的模式与机制。分子光谱和非辐射能量转移理论研究结果表明秋水仙碱通过范德华力与Hb结合,并导致Hb的构象发生改变。分子对接和分子动力学研究发现秋水仙碱在Hb的中央空腔与其形成稳定的复合物,并导致Hb的结构变得紧密,从而驱动Hb二级结构中的α-螺旋、β-转角、弯曲、无规则卷曲等结构的含量发生显著变化。Hb的某些氨基酸残基如:Trp37(β2)、Ala130(α2)、Pro90(α1)、Thr137(α1)、Tyr35(β2)等在它们结合的过程中发挥着至关重要的作用。实验数据和模拟研究结果相互印证,为进一步揭示秋水仙碱在生物体内的作用机制提供重要信息和参考依据。     

冰冻分离-气相色谱法测定自来水中微量“六六六”农药的探讨

冰凉分离法应用于环境污染物的分析,国内少见报导。本实验是将自来水样品逐渐冷冻,使纯水呈固态分离,“六六六”农药在残留溶液中被浓缩。分离出的液相注入带氚-钪源电子捕获检测器的气相色谱仪测定。方法简便,设备简单,预处理步骤少,试剂省。最少检出量:α-六六六为6.4×10~(-18)克;γ-六六六为8.8 ×10~(-13)克;β-六六六为3.7 ×10~(-13)克。回收率:α-六六六为85.0～111.8%;γ-六六六为86.0～105.0%;β-六六六为84.4～103.6%。与规范(《海洋污染调查暂行规范》国家海洋局1979年颁发)方法比较,结果令人满意。     

分散液相微萃取-高效液相色谱法测定水中α-萘酚和β-萘酚

以氯苯为萃取剂,丙酮为分散剂,采用分散液相微萃取-液相色谱联用技术对水体中的α-萘酚和β-萘酚进行分析,优化了实验条件。该方法对α-萘酚和β-萘酚的线性范围分别为1.5～50μg/L和1.0～50μg/L,检出限分别为0.9μg/L和0.5μg/L,6次重复测定的相对标准偏差分别为3.3%和1.5%。方法应用于自来水、地下水和湖水样品的分析测定,回收率在91.3%～101.0%之间。     

Quantitation of hemoglobins Bart's, H, Portland-I, Portland-II and constant spring by anion-exchange high-performance liquid chromatography

We introduce a new high-performance liquid chromatographic procedure that uses a specific anion-exchange column for the separation of hemoglobin (Hb) Bart's (gamma 4), Hb H (beta 4), Hb Portland-I (zeta 2 gamma 2), Hb Portland-II (zeta 2 beta 2), and the abnormal Hb Constant Spring (alpha 2 extended beta 2) in cord blood and adult red cell lysates. The method provides quantitative data for Hb Bart's in cord blood that correlate well with the alpha-globin gene status of the babies and can be used for an initial identification of alpha-thalassemic conditions. Quantitation of Hb Bart's from cord blood samples that are collected on filter paper and submitted as dried blood spots is unreliable. The separation of Hb H and Hb Bart's allows an evaluation of the synthesis of these two hemoglobin components in patients with Hb H disease.     

A simple flow injection-reduced volume column system for hemoglobin typing

A flow injection (FI)-reduced volume column system was developed for hemoglobin (Hb) typing to be used as an initial screening method for thalassemia. The column was packed with 140 μl diethylaminoethyl (DEAE)-Sephadex A-50 ion exchange beads. Hb can be separated using Tris–HCl buffer solution with pH gradient 8.5–6.5 and then monitored spectrophotometrically at 415 nm. The hemolysate of 40 blood samples from packed red cells were screened for thalassemia by determining the amount of HbA₂ and HbE present. The proposed system was able to predict positive test results from those samples with β, E-trait and EE homozygous thalassemia, Hb types that were independently identified following the conventional method at the hospital laboratory. Advantages of the proposed system over the conventional column technique include low amount of reagents and blood sample needed, short analysis time and low cost. Each analysis required only 80 μl of 50 times diluted packed cells, which is equivalent to 1.6 μl undiluted packed cells, and it can be completed in only 35 min. This simple FI-reduced volume column system was demonstrated to be an economic alternative system for Hb typing to initially screen some types of thalassemia such as β-trait, E-trait and EE-homozygous which are commonly found in Thailand.     

Globin chain separation by SDS polyacrylamide gel electrophoresis. Simple screening method for elongated hemoglobin chains

A simple method for the separation of hemoglobin chains from hemolysate or globin, by sodium dodecyl sulfate polyacrylamide gel electrophoresis, is described. The alpha, beta, and gamma chains can be clearly separated from each other. The alpha chain has the highest mobility, the beta chain has a slower mobility than the gamma chain, while the delta chain has about the same mobility as the beta chain. Hemoglobins with elongated chains can easily be detected by this method. Tak-beta, elongated by 11 residues, moves much more slowly than betaA but is much faster than alpha Constant Spring which is elongated by 31 residues. Screening of several individuals with slow-moving hemoglobins using this method led to the finding of a case with Hb Tak-beta thalassemia and other carriers of Hb Tak.     

Detection of the embryonic zeta chain in blood from newborn babies by reversed-phase high-performance liquid chromatography

Reversed-phase high-performance liquid chromatography (RP-HPLC) using the large-pore Vydac C4 column has been used to detect and quantitate the embryonic zeta chain in blood samples of normal babies and of newborns with varying degrees of alpha chain deficiencies. The zeta chain eluted at the end of the chromatogram at about 130 min using a modified and extended gradient. Its identity was confirmed by structural analysis of zeta chain isolated from a blood sample of a fetus without active alpha globin genes, i.e. with hydrops fetalis (--/--). The quantity of zeta in normal babies is less than 0.7% [% of (alpha + zeta)] and is dependent upon the maturity of the baby as it was only present in babies with low levels of beta chain or hemoglobin (Hb) A. The presence of a zeta globin gene deletion [A. E. Felice et al., Hum. Genet., 73 (1986) 221; and P. Winichagoon et al., Nucleic Acids Res., 10 (1982) 5853] did not affect the level of zeta in the newborn. All babies with an alpha-thalassemia-2 heterozygosity, i.e. with three active alpha globin genes or -alpha/alpha alpha, had zeta in a range of 0.1-0.9%; again the level showed a negative correlation with that of the beta chain. Newborns with an alpha-thalassemia-2 homozygosity or -alpha/-alpha had a varying level of zeta of 0.3-2.3%, which did not correlate with the level of beta, suggesting that zeta chain production persists after birth in this condition. Macrochromatographic analyses in combination with RP-HPLC indicated that the zeta chain is present as zeta 2 gamma 2 or Hb Portland-I, as expected.     

Simplified hemoglobin chain detection by capillary electrophoresis

Hemoglobin (Hb) chains have been analyzed traditionally by cellulose acetate electrophoresis after sample extraction with acetone and denaturation with concentrated urea in order to detect thalassemia (Thal). A few capillary electrophoresis (CE) methods have been also described for separation of Hb chains also after sample extraction. We describe a CE method for analysis of Hb chains without sample preparation. Red blood cells were diluted (hemolyzed) in water and injected directly onto the capillary. The separation was performed in concentrated phosphate buffer at pH 12.6 and 2.15. Under these conditions of pH and buffer concentration, the chains were denatured and separated from the heme during electrophoresis. The common variants of the beta-chains, such as beta(S), beta(C), and beta(E), are also separated from each other. The intact Hb molecule is analyzed using the same sample and CE conditions but in an arginine-Tris buffer, pH 8.6. The data from the three separations are used to complement each other for interpretation of the presence of Hb variants and for thalassemia. The main advantages of this method are simplicity and speed. This method illustrates the flexibility and simplicity of the CE for analysis of the hemoglobinopathies.     

吉林矿泉水放射性水平的调查分析

为了解吉林省矿泉水的放射性水平及分布特点,依据《饮用天然矿泉水标准》,采用FD- 125型室内氡钍测定仪及FH 463A型自动定标器和BH 1217型弱α,β测量仪对5个行政区域矿泉水中226 Ra和总α、总β放射性核素水平进行了测定.结果表明,矿泉水中226Ra、总α、总β的放射性活度范围为5.5～11.4 mBq/...     

The M gamma chain of human fetal hemoglobin; its identification and occurrence

High-performance liquid chromatographic procedures have been used in the detection and identification of a new gamma chain of human fetal hemoglobin (Hb). This M gamma chain is characterized by a Leu----Met replacement at position gamma 141; no other structural variations have been observed. The M gamma chain has been detected in red cell lysates of subjects with a heterozygosity for one of many types of so-called hereditary persistence of fetal hemoglobin conditions, which are characterized by an increased level of Hb F in adult life, in sickle cell anemia, and in a few cord blood samples. At present it is not possible to definitely identify the genetic cause of this newly discovered heterogeneity; an infidelity in translation or the existence of an unrecognized gamma globin gene should be considered.     

Review on screening and analysis techniques for hemoglobin variants and thalassemia

Thalassemia involves gene mutation that causes the production of an insufficient amount of normal structure globin chains while Hb variant involves gene mutation that causes the change in type or number of amino acid of the globin chain. It has been reported that some 200 million people worldwide had hemoglobinopathies of some sort. Attempts to develop effective and economical techniques for screening and analysis of thalassemia and Hb variants have become very important. In this review, we report the different techniques available, ranging from initial screening to extensive analysis, comparing advantages and disadvantages. Some indirect studies related to thalassemia indication and treatment follow-up are also included. We hope that information on these various techniques would be useful for some scientists who are working on development of a new technique or improving the existing ones.     

Analysis of hemoglobin and globin chain variants by a commonly used capillary isoelectric focusing method

To analyze both hemoglobin (Hb) and globin chain variants, we modified a commonly used method, capillary isoelectric focusing (CIEF), with detection at 280 nm. The samples were hemolysates prepared from red blood cells, and globin chains obtained from the hemolysates by treatment with cold acidified acetone. When the migration time for the internal reference, carbonic anhydrase I (isoelectric point, pI 6.60), was taken as 1.0, the migration ratio for Hb A0 in normal human blood was 0.877 +/- 0.004 (mean +/- SD, n = 9), and those of the alpha- and beta-globin chains were 0.673 +/- 0.004 and 0.847 +/- 0.005 (mean +/- SD, n = 4), respectively. The ratio of peak heights between the beta- and alpha-globin chains (beta/alpha) in the normal Hbs obtained from four subjects was almost constant at 2.5 +/- 0.1 (mean +/- SD). This ratio indicates which of the globin chains includes a mutation (if one exists). When an Hb variant, Hb Hoshida (in which Gln is substituted for Glu at residue 43 in the beta-globin chain), was analyzed by this method, two main peaks were observed (migration ratios 0.836 and 0.877, corresponding to an abnormal and the normal Hb, respectively). An additional peak with an abnormal migration ratio of 0.788 was also detected in the globin chain profiles. The ratio of peak heights between normal beta- and alpha-globin chains was 1.57, indicating that a mutation exists in the beta-globin chain. We thus established a convenient system using CIEF that provides a rapid and reproducible method for the random analysis of both Hb and globin chain variants.     

Analysis of the globins from fast human haemoglobins by isoelectrofocusing on polyacrylamide gel rods

The globins from all fast haemoglobin (Hb) components obtainable by Bio-Rex 70 cation-exchange chromatography were examined by isoelectrofocusing on polyacrylamide gel rods with 8.0 mol/l urea. From this analysis HbA1a1 and HbA1a2 seem to be very heterogeneous components. HbA1b is separable into two components, one of which is varied in both the beta chains. Between HbA1b2 and the well-known HbA1c components two chromatographic peaks are separated, one with a noticeable percentage of glucosylated beta chain and one that probably contains HbF. HbA1c has both beta chains glucosylated, while HbA1x seems to be a beta monoglucosylated Hb form. Finally, the early part of the HbAo peak has a large amount of glucosylation on both alpha and beta chains.