比色法与电泳法血清蛋白/球蛋白比值结果的差异分析

目的探讨比色法和电泳法测定血清蛋白/球蛋白(A/G)比值的差异情况。方法分别用双缩脲法、溴甲酚绿法、琼脂糖电泳法对384例血清标本进行总蛋白、清蛋白测定及血清蛋白电泳,计算出两种方法的A/G比值,并对数据进行统计学处理。结果比色法A/G比值(1.44±0.34),与电泳法A/G比值(1.53±0.38)相比,差异有统计学意义(P<0.01),r=0.844 7。结论比色法与电泳法A/G比值差异显著,应该建立各自方法的正常参考值。     

Thermodynamic investigation of the interaction between ionic liquid functionalized gold nanoparticles and human serum albumin for selective determination of glutamine

The excellent biocompatible and monodispersed gold nanoparticles (AuNPs) functionalized by amino based ionic liquid (IL) have been synthesized for the demonstration of their interaction with human serum albumin (HSA). Amino based IL stabilizes the surface of AuNPs and provides a colorimetric sensor platform. The size of synthesized IL–AuNPs was identified by use of transmission electron microscopy (TEM) and dynamic light scattering (DLS) techniques. Molecular interaction of functionalized AuNPs with HSA have been investigated using multispectroscopic techniques, such as UV-Vis, fluorescence and Fourier transform infra-red (FT-IR) spectroscopy. The fluorescence and synchronous fluorescent intensity together indicated that IL–AuNPs exhibits a strong ability to quench the intrinsic fluorescence of HSA via a dynamic quenching mechanism. Moreover, the binding constant (K_a), Stern–Volmer quenching constant (K_SV) and different thermodynamic parameters, namely Gibb''s free energy (ΔG), enthalpy (ΔH) and entropy (ΔS) have been evaluated at different temperatures. This interactive study focuses on the nature of surface modification of IL–AuNPs via HSA for selective detection of glutamine (Glu) with a lower limit of detection of 0.67 nM in the linear range of 10–100 nM for Glu.

The excellent biocompatible and monodispersed gold nanoparticles (AuNPs) functionalized by amino based ionic liquid (IL) have been synthesized for the demonstration of their interaction with human serum albumin (HSA).     

Characterizing the binding interaction of astilbin with bovine serum albumin: a spectroscopic study in combination with molecular docking technology

Astilbin (ASN) is a flavonoid compound isolated from the rhizome of Smilax china L. (Smilacaceae). It has many bioactivities, such as selective immunosuppression, antioxidant, anti-hepatic injury, etc., and is widely used in traditional Chinese medical treatments. The interaction of ASN with bovine serum albumin (BSA) was studied in a physiological buffer (pH = 7.40) using multi-spectroscopic techniques in combination with molecular docking methods. UV-vis absorption measurements proved that a ASN–BSA complex could be formed. Fluorescence data revealed that ASN could strongly quench the intrinsic fluorescence of BSA in terms of a static quenching procedure. The process of binding was spontaneous and the binding occurred mainly through hydrogen bonding and van der Waals forces. The distance r between donor (BSA) and acceptor (ASN) was calculated to be 4.80 nm based on Förster''s non-radiative energy transfer theory. The binding constant (K_a = 7.31 × 10⁴ mol L⁻¹) and the number of binding sites (n ≈ 1) at 298 K suggested that ASN only occupied one site in BSA with high affinity. Moreover, the results of molecular docking indicated that ASN was more likely to be located in site I (sub-domain IIA) of BSA. The results of synchronous fluorescence and three-dimensional fluorescence spectra showed that ASN induced conformational changes of BSA. The findings would be beneficial for research on the transportation, distribution and some important bioactivities of ASN in the human body.

The interaction of astilbin with bovine serum albumin was confirmed by multi-spectroscopic techniques and molecular docking methods.     

Relation between HBsAg binding with polymerized human serum albumin and HBV replication

The binding between hepatitis B surface antigen (HBsAg) and polymerized human serum albumin (poly-HSA) was studied in HBsAg-negative (25) and HBsAg-positive (92) sera by a sensitive enzyme-linked immunosorbent assay technique, and a correlation of binding activity was made with HBe-markers and hepatitis B virus-specific DNA polymerase. The binding could be detected only in HBsAg-positive sera and was found to be independent of the presence of HBe-markers and DNA polymerase activity. Further, binding was noted in significantly higher proportions of sera samples from the patient group compared with the healthy carrier group (p less than 0.01).     

Characterization of interaction between scoparone and bovine serum albumin: spectroscopic and molecular docking methods

Scoparone is a major biological active substance derived from the traditional Chinese herbal medicine called Artemisia capillaris. It has been confirmed that scoparone has anti-inflammatory, anti-tumor, hepatoprotective and antioxidant effects. However, the binding interaction of scoparone with bovine serum albumin (BSA) still remains unknown. Therefore, the present study was conducted to clarify the binding interaction of scoparone with BSA under simulated physiological conditions (pH = 7.4) by utilizing spectroscopic and molecular docking methods. The formation of the scoparone–BSA complex was identified by UV-vis absorption spectroscopy experiment results. The fluorescence experiment results revealed that the quenching mechanism was static quenching and the binding procedure was spontaneous mainly driven by hydrophobic interaction. At 310 K, the number of binding sites was approximately equal to 1 and the binding constant was 6.79 × 10⁵ mol L⁻¹. The binding distance (4.81 nm) between scoparone and BSA was determined by Förster''s non-radiative energy transfer theory. Molecular docking and site marker competitive experiment results verified that scoparone was more likely to be located in site I of BSA. In addition, the results of synchronous fluorescence spectroscopy and circular dichroism spectroscopy experiments proved that scoparone slightly changed the conformation of BSA by binding interaction with BSA. These findings would be useful for understanding the pharmacokinetics of scoparone in vivo, including scoparone transport, distribution, metabolism and excretion.

The interaction of scoparone with bovine serum albumin (BSA) was studied by utilizing spectroscopic and molecular docking methodologies.     

Materials indistinguishable from iodotyrosines in normal human serum and human serum albumin

Materials indistinguishable from authentic mono- and diiodotyrosines were identified in extracts of normal human serum as well as in extracts of purified human serum albumin. These materials were not found in association with the other serum proteins. Identification of MIT and DIT was made by a technique using rechromatography to constant specific activity, as well as by the Barker wet ash distillation method, which established the compounds in question as being iodinated ones. By two different extraction and chromatographic methods we estimated the amounts of both MIT and DIT present in normal human serum or albumin; the estimates were in good agreement. These compounds together constituted between 19% and 25% of the extractable serum iodine.     

Interaction mechanism of olaparib binding to human serum albumin investigated with NMR relaxation data and computational methods

The interaction mechanism between olaparib (OLA) and human serum albumin (HSA) has been investigated using experimental and computational techniques. An NMR relaxation approach based on the analysis of proton selective and non-selective spin–lattice relaxation rates at different temperatures can provide quantitative information about the affinity index and the thermodynamic equilibrium constant of the OLA–HSA system. The affinity index and the thermodynamic equilibrium constant decreased as temperature increased, indicating that the interactions between OLA and HSA could be weakened as temperature increased. Molecular docking and dynamics simulations revealed that OLA stably bound to subdomain II (site 1), and OLA could induce the conformational and micro-environmental changes in HSA. CD results suggested that α-helix content decreased after OLA was added, demonstrating that OLA affected the secondary structure of HSA.

The interaction mechanism between olaparib (OLA) and human serum albumin (HSA) has been investigated using experimental and computational techniques.     

Volume resuscitation from hemorrhagic shock with albumin and hexaPEGylated human serum albumin

The effect of restoring intravascular volume with polyethylene glycol (PEG) conjugated to human serum albumin (PEG-Alb) on systemic parameters and microvascular hemodynamics after hemorrhagic shock resuscitation was studied in the hamster window chamber model. Moderate hemorrhagic shock was induced by controlled arterial bleeding of 50% of blood volume, and hypovolemia was maintained for 1h. Fluid resuscitation was accomplished by infusion of 25% of blood volume and recovery was followed over 90 min. The PEG-Alb (six chains of maleimide phenyl PEG conjugated human serum albumin at 4%) resuscitation group was compared human serum albumin (HSA) at 5% (HSA5) and 10% (HSA10) protein concentrations. Systemic parameters, microvascular perfusion and capillary perfusion (functional capillary density, FCD) were measured by noninvasive methods. Hyperoncotic solutions provided rapid restoration of blood pressure, blood gas parameters and microvascular perfusion. Systemic and microvascular recovery was best and most rapid with PEG-Alb and followed by HSA10 and HSA5. Only recovery with PEG-Alb was sustained beyond 90 min. Hemodynamic functional benefits of PEG-Alb and the potential disadvantages associated with HSA, suggest PEG-Alb as better resuscitation solution.     

肾病综合征血清铁与血清白蛋白的关系分析

目的探讨肾病综合征(NS)患者血清铁(Fe)与血清白蛋白(ALB)之间的关系。方法分别对65例NS病人和正常对照组人员的血清铁和血清白蛋白进行测定。结果 NS组中的血清铁与血清白蛋白(r=0.439,P<0.001)具有相关性,差异有统计学意义;正常对照组中,血清铁与血清白蛋白间不存在相关关系,差异无统计学意义(P>0.05)。结论 NS患者中血清铁的水平与血清白蛋白之间具有紧密的关系。     

Aged human serum albumin: properties and clinical acceptibility

Sixty preparations of normal human serum albumin which had been in storage longer than the time legally permissible for suitability for clinical administration were examined. Chemical and physical measurements showed the albumins to meet all of the minimum requirements of the Division of Biologies Standards for clinically acceptable albumin. After pooling and sterilizing refiltration through 0.2 μ Millipore pads, the albumins were found acceptable for clinical use. Improvement in the clinical status of patients receiving the aged albumin compared favorably with the expected results from conventional albumin infusion. There was no evidence of adverse reactions.     

Insights into the interaction of potent antimicrobial chalcone triazole analogs with human serum albumin: spectroscopy and molecular docking approaches

Mechanistic insights into the interaction of five previously chemically synthesized triazole-linked chalcone analogs (CTs) with human serum albumin (HSA) were sought using various spectroscopic techniques (UV-visible absorption, fluorescence, and circular dichroism) and molecular docking. The fluorescence quenching experiments performed at three different temperatures (288, 298 and 308 K) revealed the static mode of quenching and the binding constants (K_b ∼ 10^6–9) obtained indicated the strong affinity of these analogs for HSA. Furthermore, significant changes in the secondary structure of HSA in the presence of these analogs were also confirmed by far UV-CD spectroscopy. The thermodynamic properties such as the enthalpy change (ΔH°), Gibbs free energy change (ΔG°) and entropy change (ΔS°) revealed that the binding process was spontaneous and exothermic. Theoretical studies, viz., DFT and molecular docking corroborated the experimental results as these five analogs could bind with HSA through hydrogen bonding and hydrophobic interactions. The present study provides useful information regarding the interaction mechanism of these analogs with HSA, which can provide a new avenue to design more potent chalcone triazole analogs for use in the biomedical field.

Mechanistic insights into the interaction of five previously chemically synthesized triazole-linked chalcone analogs with human serum albumin were analyzed using UV-visible absorption, fluorescence quenching, circular dichroism and molecular docking studies.     

The presence of halide salts influences the non‐covalent interaction of MRI contrast agents and human serum albumin

The rationale and objectives of the study were to evaluate the influence of the experimental conditions (buffer, salt, etc.) on the data characterizing the non‐covalent interaction between MRI contrast agents and human serum albumin and hence their in vivo relaxivity. The interaction of three gadolinium contrast agents (Gd‐EOB‐DTPA, Gd‐BOPTA and MP‐2269) with human serum albumin was assessed through the measurement of proton relaxation rate enhancement in various experimental conditions. The data show the negative effect of halide salts on the paramagnetic relaxation enhancement of the three contrast agents. The presence of halide salts can thus have a negative effect on the efficacy of MRI contrast agents interacting with HSA. In addition, careful attention must be paid to comparisons of the binding parameters of various contrast agents reported in different studies since the composition of the medium can greatly influence the non‐covalent interaction. Copyright © 2007 John Wiley & Sons, Ltd.     

Tumour cell delivery of antisense oligonuclceotides by human serum albumin nanoparticles.

Nanoparticles consisting of human serum albumin (HSA) and containing different antisense oligonucleotides (ASO) were prepared by desolvation. The preparation process was optimised regarding the amount of desolvating agent, stabilisation conditions as well as nanoparticle purification. The glutaraldehyde crosslinking procedure of the particle matrix was identified as a crucial parameter for biodegradability and drug release of the nanoparticles. The influence of chain length and backbone modification of ASOs on the drug loading efficiency was investigated. The loading increased with longer chain length and employment of a phosphorothioate backbone. The resulting nanoparticles were tested in cell cultures for cytotoxicity and cellular uptake. In different tumour cell lines no cytotoxic effect was observed up to nanoparticle concentrations of 5000 microg/ml. All cell lines showed a significant cellular uptake of HSA nanoparticles. The entrapment of a fluorescent labelled oligonucleotide within the particle matrix was used for the detection of the intracellular drug release of the carrier systems. Confocal laser scanning microscopy revealed that nanoparticles crosslinked with low amounts of glutaraldehyde, rapidly degraded intracellularly, leading to a significant accumulation of the ASO in cytosolic compartments of the tumour cells.