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Siqi Gao Mengmeng Zheng Yamin Lin Kecan Lin Jinshu Zeng Shusen Xie Yun Yu Juqiang Lin 《Journal of biophotonics》2020,13(8)
Combining serum albumin via adsorption‐exfoliation on hydroxyapatite particles (HAp) with surface‐enhanced Raman scattering (SERS), we developed a novel quantitative analysis of albumin method from blood serum for cancers screening applications. The quantitatively analysis obtained by our HAp method had a good linear relationship from 1 to 10 g/dL, and the lower limit of detection was less than the albumin prognostic factor for disease (3.5 g/dL). Serum albumin was adsorbed and exfoliated by HAp from serum samples of liver cancer patients, breast cancer patients and healthy volunteers and mixed with silver colloids to perform SERS spectral analysis. Based on the PLS‐SVM algorithm, the diagnostic accuracies of liver cancer patients and breast cancer patients were 100% and 96.68%, respectively. Moreover, this algorithm successfully predicted the unidentified subjects with a diagnostic accuracy of 93.75%. This exploratory work demonstrated that HAp‐adsorbed‐exfoliated serum proteins combined with SERS spectroscopy has great potential for cancer screening. 相似文献
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Chao Luo Jiasheng Wang Yongxian Hu Yi Luo Yamin Tan Aiyun Jin Bin Wei Huixian Hu He Huang 《Mycopathologia》2016,181(9-10):753-758
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本研究旨在研究B型钠尿肽(brain natriuretic peptide, BNP)对异丙肾上腺素(isoproterenol, ISO)诱导的急性心肌缺血(acute myocardial ischemia, AMI)相关损伤的保护作用。将大鼠随机分作5组:对照组、ISO处理组、ISO+普萘洛尔(5 mg/kg)处理组、ISO+BNP (5 mg/kg)和ISO+BNP (10 mg/kg)处理组。再将4个给药组中的大鼠连续2 d皮下注射ISO。通过心电图(ECG)记录ST段数据;ELISA检测血清中肌酸激酶(CK)、乳酸脱氢酶(LDH)、超氧化物歧化酶(SOD)、丙二醛(MDA)、肿瘤坏死因子-α(TNF-α)、白细胞介素-6 (IL-6)和IL-1β的表达水平;接着使用Western blotting对Bax-2、Bcl-2、PI3K、Akt、GSK-3β、MDA5和SOD1蛋白表达水平进行检测,并测定PI3K、Akt和GSK-3β的磷酸化。实验结果显示,BNP (5 mg/kg, 10 mg/kg)可降低血清中MDA和CK的表达水平以及SOD和LDH的蛋白活性;经BNP预处理显著降低了促炎因子IL-1β、IL-6和TNF-α的表达水平;同时BNP也降低了ST段抬高。此外,BNP改善了ISO诱导的大鼠中SOD1、MDA5、Bax-2、Bcl-2、p-PI3K、p-Akt和p-GSK-3β的表达。综上所述,通过调节PI3K/Akt/GSK-3β信号传导途径,BNP保护大鼠免受AMI损伤。 相似文献
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Rachel Yamin Noa S. Kaynan Ariella Glasner Alon Vitenshtein Pinchas Tsukerman Yoav Bauman Yael Ophir Shlomo Elias Yotam Bar-On Chamutal Gur Ofer Mandelboim 《PLoS pathogens》2013,9(8)
Natural killer (NK) cells are innate immune cells able to rapidly kill virus-infected and tumor cells. Two NK cell populations are found in the blood; the majority (90%) expresses the CD16 receptor and also express the CD56 protein in intermediate levels (CD56Dim CD16Pos) while the remaining 10% are CD16 negative and express CD56 in high levels (CD56Bright CD16Neg). NK cells also reside in some tissues and traffic to various infected organs through the usage of different chemokines and chemokine receptors. Kaposi''s sarcoma-associated herpesvirus (KSHV) is a human virus that has developed numerous sophisticated and versatile strategies to escape the attack of immune cells such as NK cells. Here, we investigate whether the KSHV derived cytokine (vIL-6) and chemokines (vMIP-I, vMIP-II, vMIP-III) affect NK cell activity. Using transwell migration assays, KSHV infected cells, as well as fusion and recombinant proteins, we show that out of the four cytokine/chemokines encoded by KSHV, vMIP-II is the only one that binds to the majority of NK cells, affecting their migration. We demonstrate that vMIP-II binds to two different receptors, CX3CR1 and CCR5, expressed by naïve CD56Dim CD16Pos NK cells and activated NK cells, respectively. Furthermore, we show that the binding of vMIP-II to CX3CR1 and CCR5 blocks the binding of the natural ligands of these receptors, Fractalkine (Fck) and RANTES, respectively. Finally, we show that vMIP-II inhibits the migration of naïve and activated NK cells towards Fck and RANTES. Thus, we present here a novel mechanism in which KSHV uses a unique protein that antagonizes the activity of two distinct chemokine receptors to inhibit the migration of naïve and activated NK cells. 相似文献
178.
In an effort to synthesize potent vasopressin analogs containing photoreactive groups, we prepared, by solid phase synthesis, three analogs with proline or hydroxyproline substitutions in positions 4 and/or 7, lysine in positions 4 or 8, and beta-mercaptopropionic acid in position 1. From these three parent analogs, 1-desamino[4-proline,8-lysine]VP, 1-desamino[4-hydroxyproline,8-lysine]VP, and 1-desamino[4-lysine,7-hydroxyproline]AVP, we then prepared the corresponding azido compounds using the epsilon-amino group of lysine as the attachment point. These six analogs were then assayed for antidiuretic and pressor activities in rats. One of the resulting analogs, 1-desamino[4-lysine(N epsilon-4-azidobenzoyl),7-hydroxyproline)]AVP has the highest antidiuretic activity of any photoreactive compound reported to date. 相似文献
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Development of a simple method for preparation of stable open tubular (OT) columns for proteins separation by capillary electrochromatography is still challenging. In this work, the titanium oxide (TiO2) nanoparticles coated OT column was successfully prepared for separation of proteins by capillary electrochromatography. The polydopamine (PDA) film was first formed in the inner surface of a fused-silica capillary by the self-polymerization of dopamine under alkaline conditions. Then the TiO2 coating was deposited onto the surface of pre-modified capillary with PDA by a liquid phase deposition process. The plentifully active hydroxyl groups in PDA coating can chelate with Ti4+ to boost the nucleation and growth of TiO2 film. The as-prepared TiO2 coated OT column was characterized by scanning electron microscopy and measurement of electroosmotic flow. Furthermore, the influence of liquid phase deposition time on the TiO2 coating was investigated. The TiO2 coated OT column was used for successful separation of two variants of β-lactoglobulin and eight glycoisoforms of ovalbumin. The column demonstrated good repeatability and stability. The relative standard deviations of migration times of proteins representing run-to-run, day-to-day, and column-to-column were less than 3.7%. Moreover, the application of the column was verified by successful separation of acidic proteins in egg white. 相似文献
180.
为探寻椿根皮抑菌的物质基础,该研究采用硅胶、Sephadex LH-20等方法对椿根皮甲醇提取物进行分离和纯化,通过理化性质和波谱数据分析单体化合物的结构,并以卡那霉素为对照组采用流式细胞法测试化合物的抑菌活性。结果表明:从椿根皮中得到22个化合物,分别鉴定为pleuchiol (1)、withastramonolide (2)、7-ketositosterol (3)、白桦酯醇(4)、桦木酸甲酯(5)、1, 2, 4-trimethoxybenzene (6)、顺丁烯二酸二甲酯(7)、sonderianol (8)、dibutyl phthalate (9)、pinoresinol (10)、对羟基苯甲酸乙酯(11)、avenalumic acid methyl ester (12)、5,3′-dihydroxy-3,7,4′-trimethoxy-flavone (13)、spathulenol (14)、2-甲基-5-丙基酮-7-羟基色原酮(15)、 7,4′-dihydroxyflavone (16)、annphenone (17)、3-羟基-4-甲氧基苯甲酸(18)、5,3′... 相似文献