Fourier Self-Deconvolution Analysis of β-Sheet Contents in the Amide I Region of Hemoglobin Aqueous Solutions under Exposure to 900 MHz Microwaves and Bioprotective Effectiveness of Sugar and Salt Solutions

Spectroscopic Fourier self-deconvolution analysis was used to investigate β-sheet features in the secondary structure of hemoglobin under mobile phone microwaves at 900 MHz. To this end, four samples of hemoglobin in bidistilled water, sucrose, trehalose, and sodium chloride aqueous solutions were exposed for up to 4 hr to 900 MHz microwaves at an average H-field intensity of 42 mA/m. Quantitative spectral analyses highlighted significant increases in β-sheet contents in the Amide I region of hemoglobin samples in bidistilled water solution, but no appreciable change was observed in hemoglobin samples in sucrose, trehalose, and sodium chloride solutions. These results led us to conclude that mobile phone microwaves can denaturate hemoglobin in bidistilled water solution whereas sucrose, trehalose, and sodium chloride solutions produce a protective effect against microwaves, preserving the protein from unfolding.     

One‐step Electrodeposition of Tris(hydroxymethyl) Aminomethane – Prussian Blue on Screen‐printed Electrode for Highly Efficient Detection of Glycosylated Hemoglobin

In this work, the modified Prussian blue (PB) film showed more stable performance in alkaline solution by one‐step electrodepositon of PB with tris(hydroxymethyl) aminomethane (Tris) on screen‐printed electrode (SPE). The morphology and structure of the modified Tris‐PB/SPE was characterized by scanning electronic microscopy, infra spectroscopy, Raman spectroscopy and X‐ray diffraction. It was inferred that the Tris particles embedded in the PB deposit layer resulted in the change of PB structure and improve its stability in alkaline solution. And then, the modified Tris‐PB/SPE was applied in the detection of Glycosylated hemoglobin (HbA1c). The optimum experimental conditions are pH 7.5, 100 mV/s, 4 μL FAOD and 5 min reaction time. The linearship of HbA1c is i=22.90 C+101.9 in the range of 0.1–2 mmol/L. Comparing with PB/SPE, Tris‐PB/SPE shows better sensitivity and recovery.     

1-乙烯基-3-甲基咪唑离子液体/分子印迹材料用于牛血红蛋白的识别

分子印迹聚合物是一类对目标分子具备特异性辨别能力的高分子吸附剂材料.运用本体聚合法,以牛血红蛋白(BHb)为模板分子,丙烯酰胺(AAM)和碘化1-乙烯基-3-甲基咪唑离子液体在交联剂、引发剂和加速剂的作用下进行聚合,制备的分子印迹材料对牛血红蛋白(BHb)具备特异性识别功能.同时,对识别条件进行了优化和讨论.     

A Crosslinked Nucleic Acid Nanogel for Effective siRNA Delivery and Antitumor Therapy

Functional siRNAs are employed as cross‐linkers to direct the self‐assembly of DNA‐grafted polycaprolactone (DNA‐g‐PCL) brushes to form spherical and nanosized hydrogels via nucleic acid hybridization in which small interfering RNAs (siRNAs) are fully embedded and protected for systemic delivery. Owing to the existence of multivalent mutual crosslinking events inside, the crosslinked nanogels with tunable size exhibit not only good thermostability, but also remarkable physiological stability that can resist the enzymatic degradation. As a novel siRNA delivery system with spherical nucleic acid (SNA) architecture, the crosslinked nanogels can assist the delivery of siRNAs into different cells without any transfection agents and achieve the gene silencing effectively both in vitro and in vivo, through which a significant inhibition of tumor growth is realized in the anticancer treatment.     

HbA/H2O2: an efficient biomimetic catalytic system for the oxidation of sulfides to sulfoxides

Human hemoglobin (HbA) catalyzed chemo-selective oxidation of sulfides to sulfoxides has been reported using hydrogen peroxide as an oxidant in a phosphate buffer. This biomimetic catalytic procedure was found to be simple, environmentally friendly, selective, and high yielding. Purified human oxyhemoglobin (HbA₀), crude human oxyhemoglobin, and ferryl oxyhemoglobin were used for sulfoxidation. HbA₀ and ferryl oxyhemoglobin (Fe⁺⁴O) efficiently catalyze the sulfoxidation reaction without over oxidation to the sulfone.     

异常血红蛋白酶解肽段硅胶薄板指纹图谱法的改良

本文叙述了改进的硅胶薄板指纹图谱法用于异常血红蛋白结构分析中的肽段分离工作。此法设备简单、省时省料,使用比较简陋的实验条件即可获得较好的实验结果,克服了高效液层法(HPLC)和反相高效液层法(RP—HPLC)要求设备昂贵,高压电泳法有害气体严重以及RP—HPLC的某些失活问题等     

等速电泳分析人血红蛋白

应用等速电泳（ＩＴＰ）分析了２０例健康者、１０例糖尿病患者及３例异常血红蛋白病患者的血红蛋白组分。健康者血红蛋白的ＩＴＰ分析图可分为５个部分,即ＨｂＡ_（１ａ）,ＨｂＡ_（１ｂ）＋ＨｂＡ_（１ｃ）＋ＨｂＦ,ＨｂＡ_０,ＨｂＡ_２和ＨｂＵ,并计算出各组分的均值±标准差和各组分的相对值。病理组的ＩＴＰ分析图和各组分的测定值均与健康者明显不同。     

氧钒离子作用下人血红蛋白构象变化的动态过程及2,3-二磷酸甘油酸的影响

用停流分光光度计检测在有或无DPG结合时Hb与氧钒离子作用过程中自身荧光的变化,发现无DPG的Hb自身荧光只是一个单调的荧光猝灭过程.DPG结合于Hb后的荧光变化则先为荧光猝灭,转而缓慢增加.用氧钒离子结合引起的构象变化及DPG和DPG的水解产物3PGA所起的稳定Hb四级结构作用解释了上述过程.     

Characteristics and function of human hemoglobin vesicles as an oxygen carrier

A liposome‐encapsulated human hemoglobin (Neo Red Cell, (NRC) has been developed and evaluated as an artificial oxygen carrier. The NRC is a liposome‐encapsulated highly concentrated (>45%) stroma‐free human hemoglobin with inositol hexaphosphate (IHP as an allosteric effector), a coenzyme and substrates for reducing methemoglobin (metHb). The NRC's surface was coated with polyethylene glycol to prevent aggregation in plasma and to prolong their retention time in the blood stream. The oxygen binding behavior of the NRC in vitro was investigated and it was found that it effectively transports oxygen in vivo as an oxygen carrier. The oxygen binding behavior and kinetics were studied by the stopped‐flow method and the oxygen binding curve of the NRC was determined. The oxygen binding speed and binding coefficient (K_on) of NRC, washed human red blood cells (WRBC) and stroma‐free human hemoglobin (SFHb) were measured by stopped‐flow method. The oxygen binding speed of SFHb was the highest, while that of RBC was the lowest and that of NRC was intermediate. The oxygen binding of NRC ended within 60 msec when deoxy‐NRC was mixed with oxygen. The K_on of NRC was 2.9 × 10⁵, 10 times faster than that of RBC. The oxygen binding curve and P₅₀O₂ of NRC that contained various IHP concentrations were measured. The oxygen‐binding curve of the NRC sequentially shifted to the right as the IHP content was increased. Exchange transfusion of 70% was carried out for rats with NRC containing various concentrations of IHP and of Hb, and investigated the optimum concentration of NRC in vivo. The lactate value after exchange transfusion was three times higher than before exchange transfusion, when rats were subjected to exchange transfused with NRC that did not contain IHP. But the increase of lactate was suppressed when rats were transfused with NRC that contained IHP. When the Hb concentration of NRC was 5 and 6%, exchange transfused rats recovered to normality just like rats transfused with RBC. Copyright © 2000 John Wiley & Sons, Ltd.     

New sulfonated engineering polymers via the metalation route. II. Sulfinated/sulfonated poly(ether sulfone) PSU Udel and its crosslinking

New mixed sulfinated/sulfonated polysulfone PSU Udel has been produced by partial oxidation of sulfinated PSU with NaOCl. From the mixed sulfinated/sulfonated PSU, thin crosslinked polymer films have been produced by S-alkylation of the residual sulfinate groups with α,ω-diiodoalkanes having 4–10  (CH₂) units. The advantages of the partial oxidation process using NaOCl are as follows: (1) The desired oxidation degree can be adjusted finely. (2) No side reactions take place during oxidation. (3) The partially oxidized polymers is stable at ambient temperature. By variation of the oxidation degree of the sulfinated/sulfonated prepolymer and by variation of the chain length of the diiodo crosslinker, crosslinked membranes with a large range of properties in terms of ionic conductivity, swelling, and permselectivity have been produced. The partially oxidized polymers have been characterized by redox titration, ¹H-NMR, and FTIR. The crosslinked membranes have been characterized in terms of ionic conductivity (resistance), permselectivity, and swelling in dependence on ion-exchange capacity and oxidation degree of the prepolymers. In addition, the thermal stabilities of the membranes have been determined by TGA, and FTIR spectra have been recorded on the crosslinked films. Selected membranes show low ionic resistances, low swelling, and good temperature stability which makes them promising candidates for application in (electro)membrane processes. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1441–1448, 1998