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111.
目的:研究血清Wilms瘤基因(WT1)和多药耐药基因1(MDR1)的表达与多发性骨髓瘤疾病程度的相关性。方法:采用实时荧光PCR技术对30例不同期多发性骨髓瘤患者及30例健康者静脉血清进行WT1与MDR1基因表达水平检测,并分析其表达量与多发性骨髓瘤疾病程度的影响。结果:多发性骨髓瘤患者的血清WT1与MDR1基因表达水平均明显高于普通健康者,差异具有统计学意义(P0.05);多发性骨髓瘤分期越高,患者血清WT1与MDR1基因的表达水平则越高,Ⅰ期、Ⅱ期与Ⅲ期患者的血清WT1与MDR1基因的表达水平两两组间比较差异均具有统计学意义(P0.05);WT1与MDR1基因表达水平与骨髓瘤分期呈明显的正相关性(r=0.406,r=0.451,P0.05)。结论:血清WT1与MDR1基因表达水平与多发性骨髓瘤疾病程度具有明显的正相关性,可能作为多发性骨髓瘤的临床评估预测指标。 相似文献
112.
Protein C‐terminal enzymatic labeling identifies novel caspase cleavages during the apoptosis of multiple myeloma cells induced by kinase inhibition
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Wenwen Duan Suping Chen Yang Zhang Dan Li Rong Wang Shi Chen Junbei Li Xiaoyan Qiu Guoqiang Xu 《Proteomics》2016,16(1):60-69
Caspase activation and proteolytic cleavages are the major events in the early stage of apoptosis. Identification of protein substrates cleaved by caspases will reveal the occurrence of the early events in the apoptotic process and may provide potential drug targets for cancer therapy. Although several N‐terminal MS‐based proteomic approaches have been developed to identify proteolytic cleavages, these methods have their inherent drawbacks. Here we apply a previously developed proteomic approach, protein C‐terminal enzymatic labeling (ProC‐TEL), to identify caspase cleavage events occurring in the early stage of the apoptosis of a myeloma cell line induced by kinase inhibition. Both previously identified and novel caspase cleavage sites are detected and the reduction of the expression level of several proteins is confirmed biochemically upon kinase inhibition although the current ProC‐TEL procedure is not fully optimized to provide peptide identifications comparable to N‐terminal labeling approaches. The identified cleaved proteins form a complex interaction network with central hubs determining morphological changes during the apoptosis. Sequence analyses show that some ProC‐TEL identified caspase cleavage events are unidentifiable when traditional N‐terminomic approaches are utilized. This work demonstrates that ProC‐TEL is a complementary approach to the N‐terminomics for the identification of proteolytic cleavage events such as caspase cleavages in signaling pathways. 相似文献
113.
Label‐free analysis of human cerebrospinal fluid addressing various normalization strategies and revealing protein groups affected by multiple sclerosis
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Jill A. Opsahl Marc Vaudel Astrid Guldbrandsen Elise Aasebø Vincent Van Pesch Diego Franciotta Kjell‐Morten Myhr Harald Barsnes Magnus Berle Øivind Torkildsen Ann C. Kroksveen Frode S. Berven 《Proteomics》2016,16(7):1154-1165
The aims of the study were to: (i) identify differentially regulated proteins in cerebrospinal fluid (CSF) between multiple sclerosis (MS) patients and non‐MS controls; (ii) examine the effect of matching the CSF samples on either total protein amount or volume, and compare four protein normalization strategies for CSF protein quantification. CSF from MS patients (n = 37) and controls (n = 64), consisting of other noninflammatory neurological diseases (n = 50) and non neurological spinal anesthetic subjects (n = 14), were analyzed using label‐free proteomics, quantifying almost 800 proteins. In total, 122 proteins were significantly regulated (p < 0.05), where 77 proteins had p‐value <0.01 or AUC value >0.75. Hierarchical clustering indicated that there were two main groups of MS patients, those with increased levels of inflammatory response proteins and decreased levels of proteins involved in neuronal tissue development (n = 30), and those with normal protein levels for both of these protein groups (n = 7). The main subgroup of controls clustering with the MS patients showing increased inflammation and decreased neuronal tissue development were patients suffering from chronic fatigue. Our data indicate that the preferable way to quantify proteins in CSF is to first match the samples on total protein amount and then normalize the data based on the median intensities, preferably from the CNS‐enriched proteins. 相似文献
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Spectral feature differences between shrub and grass communities and shrub coverage retrieval in shrub-encroached grassland in Xianghuang Banner,Nei Mongol,China北大核心CSCD
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Aims: Shrub-encroached grassland has become an important vegetation type in China's arid and semi-arid region. Our study objective is to explore the spectral features of shrub and grass communities, as well as their empirical relationships with shrub coverage. The quantitative estimation of shrub cover based on medium-resolution Landsat satellite imagery provides the practical basis for long term retrieval of large areas of shrub expansion in the grassland region. Methods: Linear models and Multiple Endmember Spectral Analysis Model (MESMA) based on medium resolution Landsat satellite imagery were developed to quantify the shrub coverage in a shrub-encroached grassland region in Xianghuang Banner, Nei Mongol using the spectral features and their seasonal differences between the shrub and grass communities. Important findings: Compared to Leymus chinensis and Stipa krylovii dominated grass communities, Caragana microphylla community had a higher normalized difference vegetation index (NDVI), modified red edge normalized difference vegetation index (mNDVI705), and red edge slope. The red edge position of C. microphylla community shifted to longer wavelengths. The average and the maximum shrub coverage was 13% and 25%, respectively, in the shrub-encroached grassland based on both models. The correlation coefficient of determination (R2) and root mean square error (RMSE) of the linear model was 0.31 and 0.05, respectively. We found that the linear model based on seasonal differences of shrub and grass community was more suitable for retrieving shrub coverage in the study area from medium resolution imagery than the MESMA model that is based on mid-summer images. 相似文献
118.
目的:探讨多发性肋骨骨折患者采用镍钛形状记忆合金环抱器内固定术治疗的临床效果。方法:选取2016年1月-2018年1月期间我院收治的97例多发性肋骨骨折患者。按照不同的治疗方法将患者分为对照组(n=47)和研究组(n=50),对照组患者给予胸部护板外固定术,研究组患者给予镍钛形状记忆合金环抱器内固定术。比较两组患者术后7 d的临床疗效,比较两组术前、术后7 d疼痛程度及呼吸功能情况,记录两组术后并发症发生情况。结果:研究组患者治疗后总有效率为92.00%(46/50),高于对照组患者的76.60%(36/47)(P0.05)。两组患者术后7 d视觉疼痛模拟评分量表(VAS)评分均较术前降低,且研究组低于对照组(P0.05)。两组患者术后7 d最大自主通气量占预计值百分比(MVV%)较术前升高,且研究组高于对照组(P0.05);两组患者术后7 d第1秒用力呼气肺活量占预计值百分比(FEV1%)比较无差异(P0.05)。研究组患者术后并发症总发生率8.00%(4/50),低于对照组的23.40%(11/47)(P0.05)。结论:多发性肋骨骨折经镍钛形状记忆合金环抱器内固定术治疗安全、有效,可明显减轻患者术后疼痛及改善呼吸功能,临床应用价值较高。 相似文献
119.
目的:探讨孕妇生殖道B族链球菌(GBS)感染与胎膜早破(PROM)的关系及其对母婴预后和新生儿听力筛查的影响。方法:选取2017年1月到2019年1月期间在我院接受治疗的PROM患者100例作为PROM组,另选取同期住院的正常妊娠孕妇100例作为对照组,PROM组患者根据是否合并GBS感染分为GBS阳性组和GBS阴性组。比较PROM组和对照组的GBS阳性率,比较GBS阳性组和GBS阴性组早产、胎儿窘迫、新生儿窒息、新生儿肺炎、产褥感染的发生率及新生儿听力筛查的通过率。结果:PROM组的GBS阳性率高于对照组,差异有统计学意义(P0.05)。GBS阳性组早产、胎儿窘迫、新生儿窒息、新生儿肺炎、产褥感染的发生率均明显高于GBS阴性组,差异均有统计学意义(P0.05),GBS阳性组在初筛和复筛时听力筛查通过率均低于GBS阴性组,差异均有统计学意义(P0.05)。结论:孕妇生殖道GBS感染与PROM密切相关,并可增加不良妊娠结局发生的风险,在一定程度上影响了新生儿的听力功能,对母婴预后造成不良影响。 相似文献
120.
目的:探讨蛋白激酶C受体(Receptor for activated C kinase1,RACK1)对硼替佐米(Bortezomi,Bor)诱导的多发性骨髓瘤(Multiple myeloma,MM)细胞凋亡及MAPK/ERK通路的影响。方法:选取6例岳阳市第一人民医院收治的MM患者及6名正常体检者,用实时荧光定量PCR检测血浆及人MM细胞系中RACK1 m RNA的表达。将MM细胞分为3组:对照组(不干预)、Bor组(75n M的Bor干预12 h)和Bor+siRACK1组(RACK1 si RNA转染24 h后再行Bor干预)。CCK-8法检测各组细胞中的细胞存活率,Hoechest 33342染色检测细胞凋亡,Western Blot检测MAPK/ERK通路相关蛋白表达。结果:与正常体检者相比,MM患者血浆及MM细胞系中RACK1 m RNA表达显著增加(P0.05)。Bor作用12 h、24 h和48 h可显著降低MM细胞的存活率(P0.05)。与对照组相比,Bor组和Bor+siRACK1组细胞存活率显著降低,Bor+siRACK1组细胞存活率明显高于Bor组(P0.05)。Hoechest 33342染色显示对照组细胞核染色均一,未见凋亡小体,Bor组见少量凋亡小体,而Bor+siRACK1组细胞见大量凋亡小体,表现为核固缩或碎块状;与对照组相比,Bor组和Bor+siRACK1组细胞中多发性骨髓瘤细胞凋亡率显著增加(P0.05),Bor+siRACK1组多发性骨髓瘤细胞凋亡率明显高于Bor组(P0.05)。三组间多发性骨髓瘤细胞凋亡率对比差异有统计学意义(P0.05)。与对照组相比,Bor组和Bor+siRACK1组细胞中p-P38和p-ERK的表达显著降低,而Bor+siRACK1组p-P38和p-ERK的表达低于Bor组(P0.05),3组间P38和ERK的表达对比差异无统计学意义(P0.05)。结论:RACK1沉默可增强Bor诱导的MM细胞凋亡及生长抑制,其机制可能与MAPK/ERK途径抑制有关。 相似文献