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101.
Introduction: Hydrogen deuterium exchange mass spectrometry (HDX-MS) is a powerful methodology to study protein dynamics, protein folding, protein-protein interactions, and protein small molecule interactions. The development of novel methodologies and technical advancements in mass spectrometers has greatly expanded the accessibility and acceptance of this technique within both academia and industry.Areas covered: This review examines the theoretical basis of how amide exchange occurs, how different mass spectrometer approaches can be used for HDX-MS experiments, as well as the use of HDX-MS in drug development, specifically focusing on how HDX-MS is used to characterize bio-therapeutics, and its use in examining protein-protein and protein small molecule interactions.Expert opinion: HDX-MS has been widely accepted within the pharmaceutical industry for the characterization of bio-therapeutics as well as in the mapping of antibody drug epitopes. However, there is room for this technique to be more widely used in the drug discovery process. This is particularly true in the use of HDX-MS as a complement to other high-resolution structural approaches, as well as in the development of small molecule therapeutics that can target both active-site and allosteric binding sites. 相似文献
102.
目的 利用基因芯片技术研究富氢水对γ射线照射后Beagle犬外周血淋巴细胞基因表达的影响.方法 将雄性Beagle犬随机分为对照组、单纯照射组和富氢水组(n=5),采用基因芯片技术对2.0 Gy60Coγ射线照射后6h各组Beagle犬外周血淋巴细胞的差异表达基因进行筛选,利用CGO (gene ontology)和KEGG(Kyoto encyclopedia of genes andgenomes)数据库对差异表达基因进行生物信息学分析,并应用实时荧光定量PCR技术对基因芯片结果进行验证.结果 单纯照射组筛选出差异表达2倍以上的基因4 730条,富氢水组筛选出差异表达2倍以上的基因4 493条,单纯照射组与富氢水组共同差异表达2倍以上的基因有1 606条;单纯照射组的差异表达基因对应的生物学过程、细胞组分及分子功能分别有10、9、3个功能簇,富氢水组差异表达基因对应的生物学过程、细胞组分及分子功能分别有15、3、4个功能簇.单纯照射组差异表达基因涉及19条生物学通路,富氢水组差异表达基因涉及24条生物学通路,单纯照射组与富氢水组的差异表达基因有5条共同生物学通路.选择2条差异表达基因进行mRNA水平的验证,PCR扩增结果与芯片结果具有良好的一致性.结论 富氢水对γ射线照射后Beagle犬外周血淋巴细胞基因表达的影响,可能涉及多种生物学过程、细胞组分、分子功能的改变及多条信号通路的激活. 相似文献
103.
Ronald T. Toth Samantha E. Pace Brittney J. Mills Sangeeta B. Joshi Reza Esfandiary C. Russell Middaugh David D. Weis David B. Volkin 《Journal of pharmaceutical sciences》2018,107(4):1009-1019
Antibodies are molecules that exhibit diverse conformational changes on different timescales, and there is ongoing interest to better understand the relationship between antibody conformational dynamics and storage stability. Physical stability data for an IgG4 monoclonal antibody (mAb-D) were gathered through traditional forced degradation (temperature and stirring stresses) and accelerated stability studies, in the presence of different additives and solution conditions, as measured by differential scanning calorimetry, size exclusion chromatography, and microflow imaging. The results were correlated with hydrogen exchange mass spectrometry (HX-MS) data gathered for mAb-D in the same formulations. Certain parameters of the HX-MS data, including hydrogen exchange in specific peptide segments in the CH2 domain, were found to correlate with stabilization and destabilization of additives on mAb-D during thermal stress. No such correlations between mAb physical stability and HX-MS readouts were observed under agitation stress. These results demonstrate that HX-MS can be set up as a streamlined methodology (using minimal material and focusing on key peptide segments at key time points) to screen excipients for their ability to physically stabilize mAbs. However, useful correlations between HX-MS and either accelerated or real-time stability studies will be dependent on a particular mAb's degradation pathway(s) and the type of stresses used. 相似文献
104.
Apurva S. More Ronald T. Toth Solomon Z. Okbazghi C. Russell Middaugh Sangeeta B. Joshi Thomas J. Tolbert David B. Volkin David D. Weis 《Journal of pharmaceutical sciences》2018,107(9):2315-2324
We have used hydrogen exchange–mass spectrometry to characterize local backbone flexibility of 4 well-defined IgG1-Fc glycoforms expressed and purified from Pichia pastoris, 2 of which were prepared using subsequent in vitro enzymatic treatments. Progressively decreasing the size of the N-linked N297 oligosaccharide from high mannose (Man8-Man12), to Man5, to GlcNAc, to nonglycosylated N297Q resulted in progressive increases in backbone flexibility. Comparison of these results with recently published physicochemical stability and Fcγ receptor binding data with the same set of glycoproteins provide improved insights into correlations between glycan structure and these pharmaceutical properties. Flexibility significantly increased upon glycan truncation in 2 potential aggregation-prone regions. In addition, a correlation was established between increased local backbone flexibility and increased deamidation at asparagine 315. Interestingly, the opposite trend was observed for oxidation of tryptophan 277 where faster oxidation correlated with decreased local backbone flexibility. Finally, a trend of increasing C'E glycopeptide loop flexibility with decreasing glycan size was observed that correlates with their FcγRIIIa receptor binding properties. These well-defined IgG1-Fc glycoforms serve as a useful model system to identify physicochemical stability and local backbone flexibility data sets potentially discriminating between various IgG glycoforms for potential applicability to future comparability or biosimilarity assessments. 相似文献
105.
Sara Matić Milena Jadrijević-Mladar Takač Monika Barbarić Bono Lučić Koraljka Gall Trošelj Višnja Stepanić 《Journal of pharmaceutical sciences》2018,107(11):2957-2964
The health effects of green tea are associated with catechins: (?)-epigallocatechin-3-O-gallate (EGCG), (?)-epigallocatechin, (?)-epicatechin-3-O-gallate, and (?)-epicatechin. An understanding of compound absorption, distribution, metabolism, excretion, and toxicity characteristics is essential for explaining its biological activities. Herein, absorption, distribution, metabolism, excretion, and toxicity properties of in vivo detected metabolites of green tea catechins (GTCs) have been analyzed in silico. The influence of metabolic transformations on absorption, distribution, metabolism, and excretion profiles of GTCs corresponds to the effects of size, charge, and lipophilicity, as already observed for other small molecules. Mutagenic, carcinogenic, or liver toxic effects were predicted only for a few metabolites. Similar to galloylated GTCs EGCG and (--)-epicatechin-3-O-gallate, the sulfo-conjugates were predicted to bind at the warfarin binding site. The low free plasma concentration of these derivatives may be consequential to their serum albumin binding. The activity cliff detected for methylated conjugates of EGCG indicates that GTCs' pro-oxidative activity in bound state comes primarily from free hydroxyl groups of the pyrogallol ring B. 相似文献
106.
Evaluation of a P,N‐ligated iridium(I) catalyst in hydrogen isotope exchange reactions of aryl and heteroaryl compounds 下载免费PDF全文
Mégane Valero Annina Burhop Kristof Jess Remo Weck Matthias Tamm Jens Atzrodt Volker Derdau 《Journal of labelled compounds & radiopharmaceuticals》2018,61(4):380-385
We have developed a novel and efficient iridium‐catalyzed hydrogen isotope exchange reaction method with secondary and tertiary sulfonamides at ambient temperatures. Furthermore N‐oxides and phosphonamides have been successfully applied in hydrogen isotope exchange reactions with moderate to excellent deuterium introduction. 相似文献
107.
108.
目的明确氧化应激对视网膜色素上皮细胞(RPE)中去乙酰化酶1(SIRT1)表达的影响。方法以人RPE细胞为实验对象,不同浓度H_2O_2(0、200、300μmol/L)处理RPE细胞,观察处理后24 h细胞形态的改变情况,检测处理后24 h与72 h细胞中SIRT1的mRNA与蛋白表达情况。结果 H_2O_2作用后,随H_2O_2浓度的增加,RPE细胞的形态受损,有凋亡小体的出现;在氧化应激24 h后细胞内SIRT1的转录水平增加,而在氧化应激72 h后SIRT1的蛋白表达显著下降。结论氧化应激可导致RPE细胞形态改变,SIRT1在RPE细胞内维持着氧化与抗氧化应激系统平衡,因此将SIRT1可作为临床上年龄相关性黄斑变性病(AMD)治疗的靶点。 相似文献
109.
目的探讨柚皮苷对H_2O_2诱导的H9c2心肌细胞凋亡的保护作用及机制。方法体外培养H9c2心肌细胞,用H_2O_2诱导建立细胞凋亡模型。实验设对照组、模型组、柚皮苷低、中、高剂量组(10、20、40μmol/L),噻唑蓝法检测细胞活力并用显微镜观察各组细胞形态;原位末端标记法检测H9c2心肌细胞凋亡情况;RT-PCR及Western blot法检测凋亡相关因子Bcl-2、Bax、caspase-3 m RNA及蛋白表达。结果与对照组比较,模型组细胞凋亡率[(17.2±2.1)%]明显升高(P<0.01);与模型组比较,10、20、40μmol/L柚皮苷组细胞凋亡率[分别为(10.7±1.9)%、(5.7±1.2)%、(6.4±1.5)%]均下降(均P<0.05)。与对照组比较,模型组H9c2心肌细胞Bcl-2蛋白表达水平(0.76±0.16)明显下调,Bax、caspase-3蛋白表达水平[分别为(5.42±0.52)、(1.09±0.11)]均上调(均P<0.01);与模型组比较,10、20、40μmol/L柚皮苷组H9c2心肌细胞Bcl-2蛋白表达水平[分别为(1.37±0.11)、(1.65±0.09)、(1.65±0.15)]均上调,Bax、caspase-3蛋白表达水平[分别为(2.78±0.55)、(3.43±0.15)、(2.69±0.26)和(0.59±0.08)、(0.77±0.06)、(0.82±0.05)]均下调(均P<0.05)。结论柚皮苷对H_2O_2诱导的H9c2心肌细胞损伤具有一定保护作用,其机制可能与其对凋亡信号途径的抑制作用有关。 相似文献
110.
过氧化氢与戊二醛对细菌芽胞协同杀灭作用的研究 总被引:11,自引:12,他引:11
试验表明,50%过氧化氢与05%戊二醛协同作用10~30min,对枯草杆菌黑色变种芽胞的杀灭率远高于单以过氧化氢或戊二醛作用者。戊二醛浓度对复方杀菌效果影响较大,过氧化氢浓度者次之,溶液pH影响较小 相似文献