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《Allergologia et immunopathologia》2019,47(4):357-364
IntroductionAmaranthus retroflexus (Redroot Pigweed) is one of the main sources of allergenic pollens in temperate areas. Polcalcin is a well-known panallergen involved in cross-reactivity between different plants. The aim of this study was the molecular cloning and expression of polcalcin, as well as evaluating its IgE-reactivity with A. retroflexus sensitive patients’ sera.MethodsAllergenic extract was prepared from A. retroflexus pollen and the IgE-reactivity profile was determined by ELISA and immunoblotting using sera from twenty A. retroflexus sensitive patients. Polcalcin-coding sequence was amplified by conventional PCR method and the product was inserted into pET-21b(+) vector. The recombinant protein was expressed in E. coli BL21 and purified by metal affinity chromatography. The IgE-binding capability of the recombinant protein was analyzed by ELISA and immunoblotting assays, and compared with crude extract.ResultsOf 20 skin prick test positive patients, 17 patients were positive in IgE-specific ELISA. Western blotting confirmed that approximately 53% of ELISA positive patients reacted with 10 kDa protein in crude extract. The A. retroflexus polcalcin gene, encoding to 80 amino acid residues was cloned and expressed as a soluble protein and designated as Ama r 3. The recombinant polcalcin showed rather identical IgE-reactivity in ELISA and western blotting with 10 kDa protein in crude extract. These results were confirmed by inhibition methods, too.ConclusionThe recombinant form of A. retroflexus polcalcin (Ama r 3) could be easily produced in E. coli in a soluble form and shows rather similar IgE-reactivity with its natural counterpart. 相似文献
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目的以机油为分散剂高温热解人发后发现新型纳米碳点,通过动物实验评价了该碳点的生物效应。方法利用高温热解法对人发和机油进行炭化,对炭化产物进行萃取、过滤分离和透析得到一种具有水溶性的新型物质碳点,并命名为JYRF-CDs。利用透射电子显微镜(TEM)、高分辨透射电子显微镜(HR-TEM)、紫外-可见分光光谱、傅里叶变换红外光谱、荧光光谱、X射线光电子能谱分析(XPS)等多种方法对JYRF-CDs进行表征,利用小鼠单核巨噬细胞RAW264.7细胞进行CCK-8毒性实验来评价JYRF-CDs的安全性,并通过小鼠耳肿胀实验和小鼠醋酸扭体实验对JYRF-CDs的生物效应进行评价。结果 JYRF-CDs外形为类球形,粒径均匀分布在1.8~3.6 nm,晶格间距为0.219 7 nm。细胞毒性实验结果显示,JYRF-CDs具有低毒性,动物实验结果表明JYRF-CDs具有良好的抗炎和镇痛作用。结论首次以机油为分散剂高温热解人发后发现一种全新的碳点JYRF-CDs,以JYRF-CDs为突破口,更加明确阐释以机油为分散剂高温热解人发后炭化产物具有生物效应的物质基础,为纳米类成分的研究提供了一种新方法。 相似文献
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Jesse I. Hamilton Yun Jiang Brendan Eck Mark Griswold Nicole Seiberlich 《NMR in biomedicine》2020,33(8)
This study introduces a technique called cine magnetic resonance fingerprinting (cine‐MRF) for simultaneous T1, T2 and ejection fraction (EF) quantification. Data acquired with a free‐running MRF sequence are retrospectively sorted into different cardiac phases using an external electrocardiogram (ECG) signal. A low‐rank reconstruction with a finite difference sparsity constraint along the cardiac motion dimension yields images resolved by cardiac phase. To improve SNR and precision in the parameter maps, these images are nonrigidly registered to the same phase and matched to a dictionary to generate T1 and T2 maps. Cine images for computing left ventricular volumes and EF are also derived from the same data. Cine‐MRF was tested in simulations using a numerical relaxation phantom. Phantom and in vivo scans of 19 subjects were performed at 3 T during a 10.9 seconds breath‐hold with an in‐plane resolution of 1.6 x 1.6 mm2 and 24 cardiac phases. Left ventricular EF values obtained with cine‐MRF agreed with the conventional cine images (mean bias ?1.0%). Average myocardial T1 times in diastole/systole were 1398/1391 ms with cine‐MRF, 1394/1378 ms with ECG‐triggered cardiac MRF (cMRF) and 1234/1212 ms with MOLLI; and T2 values were 30.7/30.3 ms with cine‐MRF, 32.6/32.9 ms with ECG‐triggered cMRF and 37.6/41.0 ms with T2‐prepared FLASH. Cine‐MRF and ECG‐triggered cMRF relaxation times were in good agreement. Cine‐MRF T1 values were significantly longer than MOLLI, and cine‐MRF T2 values were significantly shorter than T2‐prepared FLASH. In summary, cine‐MRF can potentially streamline cardiac MRI exams by combining left ventricle functional assessment and T1‐T2 mapping into one time‐efficient acquisition. 相似文献
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Significance of 18F-FDG PET/CT in Characterization of Equivocal Lesions in High-Risk Testicular Carcinoma in Restaging Setting 下载免费PDF全文
Rashid RasheedFareeda Al-KandariMohammad GhanemFahad MarafiSharjeel Usmani 《Asian Pacific journal of cancer prevention》2020,21(2):511-515
Objectives: The present study aims to evaluate the role of Positron emission tomography (PET) -computed tomography (CT) with 18F-fluorodeoxyglucose (18F-FDG) in the restaging of high-risk testicular cancer. Methods: Forty-five patients (mean age of 38.1±11.3 years and range 23-81 years) with testicular carcinoma, underwent 18F-FDG PET-CT during their clinical course were prospectively selected. PET positivity was defined as a site of abnormal 18F-FDG uptake in tissue histologically proven or clinically or radiographically suspected to represent tissue involvement. The sites of disease were characterized as either nodal or extranodal. All patients were followed-up for at least 12 months with a diagnostic and/or functional imaging modality. Results: Of the 45 patients 38 (84%) patient presented with seminoma and 7 (16%) were Non-seminomatous germ cell tumors. Analysis of secondary disease spectrum showed nodal involvement in 65%, osseous involvement in 23% and mixed visceral/soft tissue lesions in 12% of patients. Nineteen (42%) were negative for any metastatic disease. All negative patients remain disease free in the follow-up of one year. Out of the positive 26/45 patients, PET-CT showed progressive disease in 3/26, stable disease 1/26 and partial response in 2/26 and complete metabolic resolution in 20/26 patients. 18F-FDG PET-CT was able to characterize all patients leading to significant change of primary decision of wait and watch to go for treatment and vice versa. Conclusion: 18F-FDG PET-CT scan is potentially an excellent tool for characterization of equivocal lesions on CT scan in the restaging settings and follow up of high-risk testicular cancer patients. 相似文献
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目的:以兰州百合鳞茎中分离和纯化得到的多糖BHP-1为主要研究对象,综合运用仪器分析和化学反应等手段研究其初步的形貌特征和化学结构。方法:采用热重分析(TG)及扫描电镜(SEC)技术分别分析多糖BHP-1的热稳定性和形貌结构特征;通过气相色谱-质谱联用(GC-MS)技术,结合部分酸水解、高碘酸钠氧化-Smith降解以及核磁共振波谱(NMR)分析等方法对多糖BHP-1的化学结构进一步的进行解析。结果:BHP-1是以1,4连接的α-D-吡喃葡萄糖和1,4连接的β-D-吡喃甘露糖为基本骨架的甘露葡聚糖,在葡萄糖和甘露糖的2位和/或3位形成主要的分支,主链或支链的末端残基主要为T-α-D-吡喃葡萄糖,同时在其结构片段中含有少量的O-乙酰基。热重分析显示BHP-1在220℃开始发生降解,520℃基本结束,说明BHP-1热稳定性良好。形貌分析显示BHP-1表面光滑有大量凹陷,凹陷处多为片层结构错落紧密堆积而成,并交织下陷呈不规则的孔洞。结论:多糖BHP-1是一种热稳定性良好,表面光滑有大量的凹陷和孔洞,并含少量O-乙酰基的甘露葡聚糖,其化学结构为首次报道。 相似文献
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