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41.
《Vaccine》2020,38(43):6721-6729
The successful licensure of vaccines for biodefense is contingent upon the availability of well-established correlates of protection (CoP) in at least two animal species that can be applied to humans, without the need to assess efficacy in the clinic. In this report we describe a multivariate model that combines pre-challenge serum antibody endpoint titers (EPT) and values derived from an epitope profiling immune-competition capture (EPICC) assay as a predictor in mice of vaccine-mediated immunity against ricin toxin (RT), a Category B biothreat. EPICC is a modified competition ELISA in which serum samples from vaccinated mice were assessed for their ability to inhibit the capture of soluble, biotinylated (b)-RT by a panel of immobilized monoclonal antibodies (mAbs) directed against four immunodominant toxin-neutralizing regions on the enzymatic A chain (RTA) of RT. In a test cohort of mice (n = 40) vaccinated with suboptimal doses of the RTA subunit vaccine, RiVax®, we identified two mAbs, PB10 and SyH7, which had EPICC inhibition values in pre-challenge serum samples that correlated with survival following a challenge with 5 × LD50 of RT administered by intraperitoneal (IP) injection. Analysis of a larger cohort of mice (n = 645) revealed that a multivariate model combining endpoint titers and EPICC values for PB10 and SyH7 as predictive variables had significantly higher statistical power than any one of the independent variables alone. Establishing the correlates of vaccine-mediated protection in mice represents an important steppingstone in the development of RiVax® as a medical countermeasure under the United States Food and Drug Administration’s “Animal Rule.”  相似文献   
42.
Abstract

The aim of this study was to investigate whether elevated blood lead level (BLL) is a risk factor for Helicobacter pylori infection. Upper gastrointestinal endoscopy was performed on 2,625 subjects who visited a university hospital for general health examination. H. pylori infection was detected using histologic examination with Giemsa staining, and BLLs were measured. The mean BLL was 2.83?±?1.31?μg/dL. The prevalence of H. pylori infection was 27.8%. The BLL was significantly higher in the H. pylori infection-positive group compared to the non-infected group (2.96?±?1.33?μg/dL vs. 2.78?±?1.30?μg/dL, p?<?0.001), which remained significant after adjusting for other confounders. H. pylori infection significantly increased as the BLL increased (OR: 1.143, 95% CI 1.068–1.223). We found a relationship between BLL elevation and H. pylori infection rate.  相似文献   
43.
Multiple sclerosis (MS) is the most common inflammatory neurodegenerative disease. Neurofilament light chain (NFL) is a novel adverting biomarker of axonal damage that suggested as a useful assistant in the monitoring of MS patients. It has been shown that the auto/mitophagy associated with MS pathogenesis. In this study, we aimed to study correlation between ATG5 and Parkin, as markers of autophagy and mitophagy respectively, with NFL and ANT1 in serum and cerebrospinal fluid (CSF) in MS subjects. ATG5, Parkin, NFL, and ANT1 levels were measured in a cross-sectional study of 40 MS patients compared with gender, age and BMI matching healthy volunteers. Based on our results, levels of ATG5, Parkin, and NFL significantly were elevated in both serum and CSF of MS patients comparing control individuals (p < 0.0001) but ANT1 levels significantly was decreased in both serum and CSF of MS patients comparing control individuals (p < 0.0001). The correlation indices between NFL, ANTI1, ATG5 and Parkin in both case and control groups showed a direct and moderate the correlation between ANTI1 and ATG5 in the CSF level of the control group (r = 0.554, P = 0.011). Our data support the feasibility of quantifying of NFL as a sensitive and clinically meaningful serum/CSF biomarker to follow-up nerve tissue injury in MS condition.  相似文献   
44.
目的建立完善的鼓膜-听骨链模型,利用有限元初步探讨镫骨前、后脚骨质缺损对听力传导的影响。方法实验数据源于对一名无中耳病史的成年男性左侧颞骨进行Micro-CT扫描,在医学影像处理软件Mimics上进行三维重建,利用Geomagic形成需要的曲面,最后在SolidWorks上将成型的鼓膜-听骨链模型进行切割组装,建立正常听骨链模型以及镫骨前、后脚骨质缺损模型,利用模型分析骨质缺损对听力传导的影响。结果建立的鼓膜-听骨链模型镫骨足板频振曲线符合相关文献报道,在镫骨前、后脚骨质缺损病理模型下,曲线与正常中耳模型曲线接近。结论利用多软件综合处理,可建立可信度较高的中耳听骨链模型;有限元模拟分析结果显示,镫骨前、后脚缺损部分骨质,未对听力传导产生明显影响。  相似文献   
45.
ObjectiveWe aimed to assess serum neurofilament light chain (sNfL) levels in autism spectrum disorder (ASD) and to investigate whether they are related to the severity of disease.MethodsThe cohorts consisted of 166 children aged 3–8 (83 children diagnosed with ASD and 83 children with typically-developing). sNfL were analyzed using Single Molecule Array (Simoa) technology. ASD symptom severity was assessed according to the Chinese version of the Childhood Autism Rating Scale (CARS) score.ResultsThe mean age of those included ASD was 5.1 years (standard deviations [S.D.]: 1.7) and 78.3 % were boys. The mean (SD) sNfL concentrations were significantly (P < 0.001) higher in ASD than in TP children (10.2[5.0] pg/mL and 7.1[3.2]pg/mL). For each 1 pg/mL increase of sNfL, the risk of ASD would increase by 19 % (with the OR unadjusted of 1.19 [95 % CI 1.10–1.29], P < 0.001) and 11 % (with the OR adjusted of 1.11 [1.03–1.23], P < 0.001), respectively. sNfL concentrations in children with severe ASD were higher than in those children with mild-to-moderate ASD (12.4[5.1] pg/mL vs. 8.3[4.2]pg/mL; P < 0.001). Among ASD cases, each 1 pg/mL increase of sNfL is associated with 20 % higher unadjusted or 11 % higher adjusted odds, respectively, of severe (vs. mild-to-moderate) ASD.ConclusionsThe data showed that sNfL was elevated in ASD and related to symptom severity, suggesting that sNfL may play a role in ASD progression.  相似文献   
46.
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48.
目的 探讨长链非编码RNA(lncRNA)RGMB-AS1在脑胶质瘤病人预后评估中的作用。方法 选取2014年9月~2017年6月经术后病理检查证实的脑胶质瘤140例(低级别64例,高级别76例),另选取颅脑损伤内减压术中切取正常脑组织25例为对照。实时荧光定量PCR法检测lncRNA RGMB-AS1的表达水平,以RGMB-AS1表达量的中位数为截断值,分为高表达组和低表达组。用Kaplan-Meier法比较总体生存期(OS)和无进展生存期(PFS),用Cox比例回归风险模型分析影响胶质瘤病人预后的因素。结果 140例胶质瘤中,lncRNA RGMB-AS1高表达70例,低表达70例。胶质瘤组织lncRNA RGMB-AS1的相对表达量明显高于对照组(P<0.05)。多因素Cox比例回归风险模型分析结果显示年龄≥50岁、术前KPS评分<80分、WHO分级Ⅲ~Ⅳ级、lncRNA RGMB-AS1高表达是胶质瘤病人PFS和OS的独立影响因素(P<0.05)。lncRNA RGMB-AS1高表达胶质瘤病人PFS和OS较低表达病人均明显缩短(P<0.05)。无论是高级别胶质瘤,还是低级别胶质瘤,lncRNA RGMB-AS1高表达病人PFS和OS较低表达病人均明显缩短(P<0.05)。结论 lncRNA RGMB-AS1表达水平与脑胶质瘤病例级别呈正相关,lncRNA RGMB-AS1高表达脑胶质瘤病人生存期较低表达病人明显缩短。这提示lncRNA RGMB-AS1表达水平可作为脑胶质瘤病人预后评估指标。  相似文献   
49.
IntroductionThe goal of ossiculoplasty is to improve hearing and the success of this procedure depends on several factors.ObjectiveAnalyze the hearing results in patients with chronic otitis media undergoing ossicular chain reconstruction, as well as predictive factors for successful surgery.MethodsCharts of patients undergoing ossiculoplasty between 2006 and 2016 were reviewed. Sixty-eight patients were included, totaling 72 ears. The following data was analyzed: gender, age, smoking status, laterality, pathology, audiometric exams, type of surgery, previous surgery, characteristics of the middle ear, otorrhea and ossicular chain status. Patients were also classified according to two indices: middle ear risk index and ossiculoplasty outcome parameter staging. The results were evaluated by comparing the air-bone gap before and after surgery. The success of reconstruction was defined as air-bone gap ≤20 dB and the improvement of speech reception Thresholds, calculated through the mean frequencies 0.5, 1, 2 and 3 kHz.ResultsReconstruction success rate was 61%. The mean preoperative air bone gap was 34.63 dB and decreased to 17.26 dB after surgery. There was a correlation between low risk in middle ear risk index and ossiculoplasty outcome parameter staging indices with postoperative success. The most frequently eroded ossicle was the incus and the type of prosthesis most used was tragal cartilage. In the patients without incus, we achieved success in 74.2% of the surgeries. In the absence of the stapes, the success rate decreased to 63.3%. In the absence of the malleus, 85% of the patients had and air bone gap ≤20 dB.ConclusionWe achieved good audiometric outcomes in ossiculoplasty and the results are comparable to other centers. Ossicle status influenced postoperative results, especially in the presence of stapes. We also concluded that the indexes analyzed may help to predict the success of the surgery.  相似文献   
50.
目的:分析NM II-C在斑马鱼胚胎发育过程中表达的时空变化。方法:收集不同发育阶段的斑马鱼胚胎,应用整体原位杂交技术研究NM II-C在斑马鱼胚胎发育过程中的表达变化情况。结果:受精后17和22小时,NM II-C由原先的广泛表达渐渐集中于前脑、中脑和后脑;受精后26和36小时,NM II-C表达分布到整个中枢神经系统;受精后48小时,NM II-C表达在脊髓变得很弱,主要集中于大脑。结论:揭示了NM II-C基因在斑马鱼胚胎发育过程中的时间和空间上的表达进程,为进一步探讨其在发育中的调控作用提供了实验基础。  相似文献   
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