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1.
BackgroundSerum LacdiNAc-glycosylated prostate-specific antigen (LDN-PSA) and LDN-PSA density together with PSA and PSA density (PSAD) were measured as a diagnostic tool for prostate cancer (PCa).Patients and MethodsWe included 150 patients with PCa without hormonal therapy and 41 patients without PCa obtained from the Kyoto University Hospital between 2012 and 2017. LDN-PSA levels were measured through a WFA–anti-PSA antibody sandwich immunoassay using a highly sensitive surface plasmon field-enhanced fluorescence spectroscopy (SPFS) system. Diagnostic performance of serum LDN-PSA and LDN-PSAD was evaluated by measuring the area under the receiver-operating characteristic curve (AUC).ResultsThe AUCs of LDN-PSA, LDN-PSAD, and PSAD levels (0.780, 0.848, and 0.835, respectively) detected in patients with PCa were significantly higher (P = .0001, P < .0001, and P < .0001, respectively) than that of PSA (0.590). Moreover, among 143 patients with PCa who received radical prostatectomy (RP), the AUCs of LDN-PSA, LDN-PSAD, and PSAD levels (0.750, 0.812, and 0.769, respectively) detected in patients with a pathologic Gleason grade group ≥ 2 were significantly higher (P = .0170, P = .0028, and P = .0003, respectively) than that of PSA (0.578). In the group comprising 35 patients who received RP with a Gleason grade group 1-graded biopsy, the LDN-PSA, LDN-PSAD, and PSAD levels were significantly different (P = .0097, P = .0024, and P = .0312, respectively). However, PSA alone could not discriminate cases with adverse features (P = .454).ConclusionsLDN-PSAD is a potential marker for detecting PCa and selecting candidates for RP.  相似文献   
2.
目的 应用液相色谱-质谱法(liquid chromatography-mass spectromety,LC/MS)和液相色谱-非数据依赖二级质谱数据采集技术(liquid chromatography-data independent acquisition mass spectromety,LC/MSE)对利妥昔单抗及其类似药进行结构表征和相似性研究.方法 用LC/MS对利妥昔单抗及其类似药的完整蛋白及轻链和重链的相对分子质量进行测定;用基于LC/MSE的肽图分析确定利妥昔单抗及其类似药的氨基酸全序列;用LC/荧光检测法分析利妥昔单抗的糖基化修饰结构及相对含量.结果 LC/MS可准确测定利妥昔单抗的相对分子质量.基于LC/MSE的肽图分析显示,利妥昔单抗的氨基酸序列覆盖率>99%.LC/荧光检测法对利妥昔单抗的糖谱分析具有较好的重复性.利妥昔单抗类似药与原研药的相对分子质量和糖型信息相符、氨基酸序列完全一致、糖谱相似.结论 LC/MS和LC/MSE可用于利妥昔单抗及其类似药的结构表征和相似性比较,这为今后其他单克隆抗体结构表征平台的建立提供了依据.  相似文献   
3.
目的观察聚嘧啶束结合蛋白相关剪接因子(PSF)高表达对糖基化终末产物(AGEs)诱导下RPE细胞损伤的保护作用。方法将体外培养的人RPE细胞分为正常对照组(N组)、空白对照组(N+AGAGEs组)、空载体对照组(Vec+AGEs组)、PSF高表达组(PSF+AGEs组)。N组RPE细胞常规培养;N+AGEs组只做转染处理但不导入任何外源性基因的RPE细胞联合AGEs诱导;Vec+AGEs组、PSF+AGEs组利用转染试剂脂质体2000将pcDNA空载体或pcDNA-PSF真核表达质粒导入RPE细胞联合AGEs诱导。除N组以外,其余3组细胞进行相应的转染处理,24 h后应用150μg/ml的AGEs刺激72 h。采用HE染色和Hoechst 33258染色观察PSF高表达对RPE细胞凋亡相关形态改变的影响;通过ROS水平检测分析PSF高表达对AGEs诱导的RPE细胞ROS表达的影响;采用MTT比色法检测PSF高表达对RPE细胞生存力的影响;采用Western blot检测PSF不同作用时间及不同剂量对血红素氧合酶1(HO-1)表达的影响。结果HE染色和Hoechst 33258染色观察发现,N组细胞形态饱满,细胞核呈圆形,细胞质丰富,染色均一;N+AGEs组、Vec+AGEs组细胞体积缩小,嗜酸性染色增强,细胞核致密浓染、固缩甚至碎裂;PSF+AGEs组细胞形态尚饱满,细胞浆染色较均匀,细胞核染色均一。MTT比色法检测结果显示,PSF高表达可有效提高RPE细胞生存力,但该作用可被ZnPP有效拮抗,且差异有统计学意义(F=33.26,P<0.05)。DCFH-DA法检测结果显示,与N+AGEs组、Vec+AGEs组比较,PSF+AGEs组细胞中ROS产量下降,差异有统计学意义(F=11.94,P<0.05)。Western blot检测结果显示,PSF蛋白以时间、剂量依赖性的方式上调HO-1的表达水平。PSF蛋白作用24、48、72 h的HO-1相对表达水平较0 h明显升高,差异有统计学意义(F=164.91,P<0.05)。0.1、0.5、1.0、1.5、2.0μg PSF蛋白作用下的HO-1相对表达水平较0.0μg明显升高,差异有统计学意义(F=104.82,P<0.05)。结论PSF可能通过上调HO-1的表达而抑制ROS产生,从而对AGEs诱导下的RPE细胞损伤发挥保护作用。  相似文献   
4.
目的:考察葡萄糖基化丙泊酚溶液型注射剂在大鼠体内的药物动力学。方法:建立液相色谱-高分辨质谱联用方法,用以测定大鼠体内丙泊酚血药浓度;通过对大鼠尾静脉给药,分别给予丙泊酚脂肪乳剂型注射剂和两种葡萄糖基化丙泊酚溶液型注射剂,测定丙泊酚血药浓度,获得药物-时间曲线,并计算药物动力学参数。结果:用C18色谱柱,以水 ∶甲醇(20 ∶80,V/V)为流动相,用四极杆-轨道阱高分辨质谱仪进行检测,使用大气压化学电离源,负离子检测,扫描方式采用选择离子监测方式,m/z=177.127 4(丙泊酚), m/z=149.096 1(麝香草酚,内标参照物)。测定方法在50 μg/L~10.0 mg/L范围内线性关系良好,最低定量浓度为50 μg/L,平均回收率在93.6%~101.1%之间,日内、日间精密度均小于14%。药物动力学结果显示,两种葡萄糖基化丙泊酚溶液型注射剂药物动力学行为一致;同丙泊酚脂肪乳剂型注射剂相比,两种葡萄糖基化丙泊酚溶液型注射剂清除率均明显加快,表观分布容积也相应增大,血液循环中血药浓度-时间曲线下面积减小,消除半衰期与丙泊酚脂肪乳剂型注射剂一致(t1/2约1.5 h)。结论:建立的液相色谱-高分辨质谱联用方法可以用于大鼠体内丙泊酚含量的测定;与丙泊酚脂肪乳剂型注射剂相比,葡萄糖基化丙泊酚溶液型注射剂具有在血液循环中清除率加快、表观分布容积大的特点。  相似文献   
5.
Herein we will review the role of glycans in the immune system. Specific topics covered include: the glycosylation sites of IgE, IgM, IgD, IgE, IgA, and IgG; how glycans can encode “self” identity by functioning as either danger associated molecular patterns (DAMPs) or self-associated molecular patterns (SAMPs); the role of glycans as markers of protein integrity and age; how the glycocalyx can dictate the migration pattern of immune cells; and how the combination of Fc N-glycans and Ig isotype dictate the effector function of immunoglobulins. We speculate that the latter may be responsible for the well-documented association between alterations of the serum glycome and autoimmunity. Due to technological limitations, the extent of these autoimmune-associated glycan alterations and their role in disease pathophysiology has not been fully elucidated. Thus, we also review the current technologies available for glycan analysis, placing an emphasis on Multiple Reaction Monitoring (MRM), a rapid high-throughput technology that has great potential for glycan biomarker research. Finally, we put forth The Altered Glycan Theory of Autoimmunity, which states that each autoimmune disease will have a unique glycan signature characterized by the site-specific relative abundances of individual glycan structures on immune cells and extracellular proteins, especially the site-specific glycosylation patterns of the different immunoglobulin(Ig) classes and subclasses.  相似文献   
6.

Background

Increased body fat may be associated with an increased risk of developing an underlying pro-inflammatory state, thus leading to greater risk of developing certain chronic conditions. Immunoglobulin G has the ability to exert both anti- and pro-inflammatory effects, and the N-glycosylation of the fragment crystallisable portion is involved in mediating this process. Body mass index, a rudimentary yet gold standard indication for body fat, has been shown to be associated with agalactosylated immunoglobulin G N-glycans.

Aim

We aimed to determine the association between increased body fat and the immunoglobulin G glycosylation features, comparing body mass index to other measures of body fat distribution.

Methods

We investigated a sample of 637 community-based 45–69?year olds, with mixed phenotypes, residing in Busselton, Western Australia. Body mass index and the waist-to-hip and waist-to-height ratios were calculated using anthropometry, while dual-energy x-ray absorptiometry was performed to gain an accurate measure of total and area specific body fat. Serum immunoglobulin GN-glycans were analysed by ultra-performance liquid chromatography.

Results

Twenty-two N-glycan peaks were found to be associated with at least one of the fat measures. While the previous association of body mass index to agalactosylated immunoglobulin G was replicated, measures of central adiposity explained the most variation in the immunoglobulin G glycome.

Conclusion

Central adiposity is associated with an increased pro-inflammatory fraction of immunoglobulin G, suggesting that the android/gynoid ratio or waist-to-height ratio instead be considered when controlling for adiposity in immunoglobulin G glycome biomarker studies.  相似文献   
7.
目的:探讨急性主动脉夹层(AAD)患者血清高迁移率族蛋白B1(HMGB1)与晚期糖基化终产物受体(RAGE)水平与继发急性肺损伤的关系。 方法:选取2016年3月—2018年5月经全主动脉CTA以及超声心动图等影像学检查明确诊断的AAD患者56例为研究对象。按静态吸氧状态下氧合指数(PaO2/FiO2)大小将患者分为肺损伤组(21例)与非肺损伤组(35例)。随机选取健康体检人员30例为对照组。AAD患者入院后每4 小时抽血次,对照组受试者仅抽取1次清晨空腹肘静脉血。采用ELISA法检测血清HMGB1、RAGE水平,同时检测PaO2、计算PaO2/FiO2。 结果:与健康对照组比较,两组AAD患者入院后24 h的HMGB1、RAGE水平均明显高于健康对照组,且两者在肺损伤组均明显高于非肺损伤组(均P<0.05)。两组AAD患者入院后HMGB1、RAGE水平不断上升,而PaO2/FiO2逐渐降低,并均入院后48~60 h达到峰值,肺损伤组的3项指标的变化幅度均明显大于非肺损伤组(均P<0.05);随着发病时间的推移,HMGB1、RAGE水平达到峰值后下降,PaO2/FiO2逐渐回升。AAD患者中,HMGB1与RAGE水平与PaO2/FiO2均呈明显负相关(r=-0.940、 -0.794)。 结论:HMGB1/RAGE信号通路可能在AAD肺损伤中发挥着重要的作用,随着HMGB1、RAGE水平的升高,肺损伤程度逐渐加重,监测HMGB1、RAGE水平可以对AAD并发肺损伤的风险进行评估;对HMGB1/RAGE信号通路深入研究可能会为AAD肺损伤的干预提供靶点。  相似文献   
8.
目的 探讨组织蛋白酶D(CTSD)新的糖基化异构体与肺癌临床病理特征及预后的相关性。 方法 应用免疫组织化学和半定量RT PCR方法检测119例肺癌组织和39例癌旁组织中CTSD的表达;Western blotting分析CTSD各异构体表达特点;去糖基化实验检测CTSD 蛋白的糖基化修饰;Kaplan-Meier分析66kD异构体、临床病理资料与肺癌术后整体生存期的相关性。 结果 CTSD在肺鳞癌、腺癌和小细胞肺癌组织中高表达;66kD蛋白为CTSD新的糖基化异构体,该异构体表达与肺癌组织类型、临床分期、淋巴结转移和患者的吸烟史密切相关(P<0.05),阳性表达和阴性表达患者术后中位生存时间分别为20.0和30.0个月(P<0.05);肺癌组织类型、临床分期、淋巴结转移、肿瘤大小和66kD异构体表达是影响肺癌预后的独立因素。 结论 CTSD 66kD异构体阳性表达可能是肺癌预后不良的分子标志物之一。  相似文献   
9.
Three well-known natural diosgenyl glycosides which have the same sugar chains but different sequence, ophipogonin C′, polyphillin C and prosapogenin B, were synthesised by a facile approach. A method using the levulinyl group as a protecting group to selectively mask the C3–OH of diosgenyl 4,6-O-benzylidene-β-d-glucopyranoside is described.  相似文献   
10.

Background

The mutations of LHBs in pre-S, especially in pre-S2, are definitive in hepatocellular carcinoma (HCC) associated with HBV. However, the mechanisms of the N-glycosylation modification in LHBs are unclear. The N-glycosylation modification of LHBs affects Endoplasmic Reticulum stress, cell proliferation and its secretion which was further studied.

Objectives

The objectives of our studies was to indentified that modification of LHBs by N glycosylation modulate their secretion, affect ER stress or expression of cycling, cell cycle and proliferation.

Materials and Methods

The LHBs was mutated; then expression of proteins related to endoplasmic reticulum stress and EAED path of L02 cells affected by LHBs and its mutations was evaluated. LHBs proteins bound to multiubiquitin chains and its glycosylation motif were studied. The subcellular localization and secretion of LHBs and its mutations were identified. The effect on cell cycle and proliferation by LHBs and its mutations were detected.

Results

These data demonstrated that the N-glycosylation motifs of LHBs were associated with ER stress. The N15S, N123S, and N177S mutated LHBs proteins could induce overexpression of EDEM in L02 cells. LHBs and its mutated proteins contained p62-derived UBA domain, which could affect expression of cyclins. The subcellular localization of LHBs in endoplasmic reticulum was similar to its mutations. The secretion of LHBs was blocked by N320K mutation, which could induce an increase in G1 phase and inhibition of S phase, and inhibited mitotic entry.

Conclusions

In conclusion, our studies powerfully demonstrated that modification of LHBs by N glycosylation could modulate their secretion, affect ER stress or expression of cycling, cell cycle and proliferation. The N320K may be the key sites N-linked glycosylation modification of LHBs. It may be a mechanism of HBV-induced HCC.  相似文献   
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