异丙威荧光分子印迹聚合物的制备

以石墨烯量子点(GQDs)为荧光组分,异丙威为模板分子,甲苯/石蜡混合溶剂为致孔剂,甲基丙烯酸为功能单体,三羟甲基丙烷三丙烯酸酯为交联剂,偶氮二异丁腈为引发剂,采用热引发沉淀聚合法制备了对异丙威有吸附作用的异丙威荧光分子印迹聚合物。结果表明:异丙威荧光分子印迹聚合物表面凹凸不平,直径较大;其与甲基丙烯酸之间以非共价键结合;荧光分子印迹聚合物内部存在大量印迹"空洞"或"孔穴",对高温有一定的耐受性;异丙威荧光分子印迹聚合物具有良好的吸附性、荧光性、选择特异性,可为环境、食品中农药痕量残留检测提供一种新途径。     

邻苯二甲酸二丁酯分子印迹聚合物的制备及性能研究

以邻苯二甲酸二丁酯(DBP)为模板分子,甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EGD-MA)为交联剂,采用沉淀聚合法制备了分子印迹聚合物。通过静态平衡结合法和Scatchard分析法,研究了分子印迹聚合物的识别性能和结合能力。结果表明,该分子印迹聚合物对模板分子DBP具有较强的吸附特性和很好的选择性,其识别因子可达4.19。Scatchard分析表明,印迹聚合物微球存在2类不同的结合位点。高结合位点的平衡离解常数Kd1=0.078 mg/L,最大表观结合量Qmax1=53.03 mg/g;低结合位点的离解常数Kd2=0.023 mg/L,最大表观结合量Qmax2=33.95 mg/g。     

沉淀聚合法制备吲哚乙酸印迹聚合物及其吸附性能研究

以吲哚乙酸(IAA)为模板分子、乙腈为致孔剂,采用沉淀聚合法制备了其分子印迹聚合物,通过静态吸附实验研究了致孔剂乙腈的用量及4-乙烯基吡啶(4-VP)和丙烯酰胺(AA)两种不同性质的功能单体(M)对印迹聚合物吸附性能的影响。结果表明,以4-VP为M,乙腈的加入量分别为20、25、37.5和50 m L时,制备的印迹聚合物P1~P4均具有良好的分散性,且聚合物P4对IAA具有最显著的印迹效应(印迹因子IF=2.92);而在同样条件下以AA为M的印迹聚合物的印迹效应较小(IF=1.73)。选择性实验表明,聚合物P4能够从吲哚羧酸同系物中选择性结合IAA。Scatchard分析表明,聚合物P4对IAA表现出两类结合位点,其高亲和力与低亲和力结合位点的平衡离解常数分别为Kd1=0.798 mmol/L和Kd2=7.76 mmol/L,对应的最大结合量分别为21.0和90.7μmol/g。     

二氯喹啉酸分子印迹聚合物微球的制备

采用改进的分散聚合方法制得的纳米级聚苯乙烯微球(PS)为种球,以二氯喹啉酸(quinclorac)为模板分子,通过单步溶胀聚合法在水相中制备了单分散分子印迹聚合物微球(MIPs)。通过红外光谱分析MIPs的结合位点;利用紫外光谱研究了MIPs的结合机理和识别特性;用扫描电镜观察了微球的形貌。结果表明,PS微球的粒径分布100～150nm,MIPs的粒径分布为200～300nm;Scatchard分析表明,MIPs在识别二氯喹啉酸过程中存在两类结合位点:高亲和性位点的解离常数KD1=0.0488mmol/L;低亲和性位点的解离常数KD2=0.423mmol/L。     

溶胶-凝胶法制备链霉素分子表面印迹聚合物及其性能表征

以四氢呋喃、乙醇和水的混合溶液(体积比6∶1∶1)为分散剂,3-氨基丙基三乙氧基硅烷和苯基三乙氧基硅烷为功能单体,正硅酸乙酯为交联剂,氨水为催化剂,通过溶胶-凝胶法在二氧化硅微球表面制备了分子印迹聚合物。用分子对接的方法初步分析了链霉素与功能单体和交联剂之间的相互作用,验证了它们形成氢键的可能性。活化时间会影响分子印迹微球的形貌。吸附实验表明,分子印迹微球比非印迹聚合物微球对链霉素具有更优越的吸附性能和选择性。     

乙酰水杨酸分子印迹聚合物微球的制备及性能研究

以乙酰水杨酸为模板分子,采用沉淀聚合的方式制备了对乙酰水杨酸具有高选择性和亲和性的分子印迹聚合物微球。通过紫外光谱分析法考察了模板分子与功能单体作用规律,优选了功能单体与配合比例。等温吸附实验的结果显示,与相应的空白聚合物相比,印迹聚合物对模板分子具有更高的亲和性;Scatchard数学模型分析的结果表明,印迹聚合物中主要存在一类亲和性质相同的结合位点,其最大表观结合量为37.97 mg/g。选择性吸附实验表明,制备的印迹聚合物对模板分子具有良好的选择性识别能力。     

和厚朴酚分子印迹聚合物微球的制备及表征

采用单步溶胀聚合法制备了和厚朴酚分子印迹聚合物微球(MIPMs)。Scatchard分析表明分子印迹聚合物微球在识别和厚朴酚分子的过程中存在两类结合位点,其高亲和位点的解离常数为KD1=0.13 mmol/L,最大表观结合量Qmax=45.21μmol/g。静态吸附试验证明MIPMs对模板分子具有较强的特异吸附能力,以厚朴酚为竞争底物,其分离因子达1.85。     

红霉素分子印迹聚合物纳米微球的制备及其吸附特性

以红霉素为模板分子、甲基丙烯酸为功能单体、乙二醇二甲基丙烯酸酯为交联剂,采用沉淀聚合法制备了粒径均一的红霉素纳米分子印迹聚合物微球,优化了分子印迹聚合物的合成条件,确定了模板分子与功能单体的最佳摩尔比为1:3,对其进行了表征. 结果表明,所制聚合物对红霉素的实际最大吸附量可达202.12 mg/g,吸附约200 min达到平衡,对红霉素具有良好的选择性吸附能力.     

罗丹明B分子印迹聚合物的制备及分子识别性能研究

以三苯甲烷类碱性染料罗丹明B为模板分子,丙烯酰胺为功能分子,N,N-亚甲基双丙烯酰胺(MBA)为交联剂,采用表面修饰分子印迹法,制备对罗丹明B具有特定亲和选择性的分子印迹聚合物。应用红外光谱对印迹聚合物进行表征,通过静态吸附实验对聚合物的吸附动力学进行分析,采用平衡结合实验评价了分子印迹聚合物的吸附性能。结果表明,采用表面修饰分子印迹法所制备的印迹聚合物对罗丹明B表现出较好的特异吸附,对模板分子最大吸附量值为96μmol/g。     

硫丹分子印迹聚合物的合成及吸附特性分析

采用分子印迹技术,以α-甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,偶氮二异丁腈为引发剂,乙腈为致孔剂,合成以硫丹为模板的印迹聚合物微球。首先利用紫外光谱方法研究了模板与功能单体相互作用情况,采用平衡吸附试验对印迹聚合物吸附效率进行了表征,与化学组成相同的空白聚合物相比,印迹聚合物微球对模板分子具有更高的吸附效率,按最佳合成条件得到的印迹聚合物最大表观吸附量达42.56 mmol/g。     

椰壳生物碳和海藻酸钙/生物碳复合材料的制备及其对Cu(II)的吸附性能和机制

利用海藻酸钙（CA）包覆生物碳（BC7）制备了一种新型复合材料（CA/BC7）,用以吸附水溶液中的Cu(II)。系统的研究了Cu(NO3)2溶液初始浓度、pH、时间对Cu(II)吸附的影响。BC7、CA/BC7吸附Cu(II)等温热力学数据符合Langmuir模型,在pH=5的条件下对Cu(II)的最大吸附量分别为20.28 mg?g-1,35.46 mg?g-1。BC7、CA/BC7吸附Cu(II)动力学数据符合准一动力学模型,扩散是速率控制步骤。研究表明：BC7吸附Cu(II)的机制包括形成Cu(II)-O-Si以及形成Cu(II)-Complex配合物;CA/BC7吸附Cu(II)的机制主要包括形成配合物,以及Ca(II)与Cu(II)发生离子交换。     

The Prognostic Impact of Retinoid X Receptor and Thyroid Hormone Receptor alpha in Unifocal vs. Multifocal/Multicentric Breast Cancer

The aim of this study was to assess the prognostic value of the steroid hormone receptor expression, counting the retinoid X receptor (RXR) and thyroid hormone receptors (THRs), on the two different breast cancer (BC) entities: multifocal/multicentric versus unifocal. The overall and disease-free survival were considered as the prognosis determining aspects and analyzed by uni- and multi-variate analysis. Furthermore, histopathological grading and TNM staging (T = tumor size, N = lymph node involvement, M = distant metastasis) were examined in relation to RXR and THRs expression. A retrospective statistical analysis was carried out on survival-related events in a series of 319 sporadic BC patients treated at the Department of Gynecology and Obstetrics at the Ludwig-Maximillian’s University in Munich between 2000 and 2002. The expression of RXR and THRs, including its two major isoforms THRα1 and THRα2, was analyzed by immunohistochemistry and showed to have a significant correlation for both BC entities in regard to survival analysis. Patients with multifocal/multicentric BC were exposed to a significantly worse disease-free survival (DFS) when expressing RXR. Patients with unifocal BC showed a significantly worse DFS when expressing THRα1. In contrast, a statistically significant positive association between THRα2 expression and enhanced DFS in multifocal/multicentric BC was shown. Especially the RXR expression in multifocal/multicentric BC was found to play a remarkably contradictory role for BC prognosis. The findings imply the need for a critical review of possible molecular therapies targeting steroid hormone receptors in BC treatment. Our results strengthen the need to further investigate the behavior of the nuclear receptor family, especially in relation to BC focality.     

A Signature of Four Circulating microRNAs as Potential Biomarkers for Diagnosing Early-Stage Breast Cancer

Breast cancer (BC) is the most predominant type of cancer among women. The aim of this study is to find new biomarkers that can help in early detection of BC, especially for those who are too young to be screened using mammography as per guidelines. Using microRNA microarray, we previously showed dysregulation of 74 microRNAs in tumors from early BC patients as compared with normal adjacent tissues, which we were interested in studying in blood circulation. In this study, we investigated the expression of 12 microRNA (miR-21/miR-155/miR-23a/miR-130a/miR-145/miR-425-5p/miR-139-5p/miR-451/miR-195/miR-125b/miR-100, and miR-182) in the plasma of 41 newly diagnosed Lebanese BC patients with early invasive ductal carcinoma as compared with 32 healthy controls. Total RNA was extracted from plasma, and expression levels of miRNA of interest were measured using RT-qPCR followed by statistical analysis; miR-21, miR-155, miR-23a, miR-130a, miR-145, miR-425-5p, and miR-139-5p were significantly upregulated and miR-451 was significantly downregulated, in the plasma of BC patients as compared with healthy controls. The positively correlated miR-23a, miR-21, and miR-130a had a high diagnostic accuracy (86%). Importantly, the combination of miR-145/miR-425-5p/miR-139-5p/miR-130a scored the highest diagnostic accuracy of 95% with AUC = 0.97 (sensitivity 97% and specificity 91%). MicroRNAs are promising non-invasive diagnostic biomarkers for early-stage BC with the panel of miR-145/miR-425-5p/miR-139-5p/miR-130a having the highest diagnostic accuracy.     

Synthesis of Al3BC in air from mechanically activated Al/B/C powder mixtures

A ternary aluminum borocarbide, Al₃BC was prepared for the first time by self-propagating high-temperature synthesis (SHS) induced by mechanical activation of Al/B/C powder mixtures in air. The effect of mixing molar ratio of Al/B/C and grinding time on the formation of Al₃BC was investigated. On the other hand, Al₃BC was also formed by mechanical activation and subsequent annealing of Al/B/C=3/1/1 powder mixture. The lattice constants of Al₃BC obtained in two methods were compared.     

Expression of Irisin/FNDC5 in Breast Cancer

Irisin is a myokine formed from fibronectin type III domain-containing protein 5 (FNDC5), which can be found in various cancer tissues. FNDC5 and irisin levels have been poorly studied in the tumor tissues of breast cancer (BC). The aim of this study was to determine the levels of irisin expression in BC tissues and compare them to clinicopathological factors and Ki-67 and PGC-1α expression levels. Tissue microarrays (TMAs) with 541 BC tissues and 61 samples of non-malignant breast disease (NMBD; control) were used to perform immunohistochemical reactions. FNDC5 gene expression was measured in 40 BC tissue samples, 40 samples from the cancer margin, and 16 NMBD samples. RT-PCR was performed for the detection of FNDC5 gene expression. Higher irisin expression was found in BC patients compared to normal breast tissue. FNDC5/irisin expression was higher in patients without lymph node metastases. Longer overall survival was observed in patients with higher irisin expression levels. FNDC5/irisin expression was increased in BC tissues and its high level was a good prognostic factor for survival in BC patients.     

The contributions of “minimum primary emissions” and “new particle formation enhancements” to the particle number concentration in urban air

In an urban site affected by fresh vehicle exhaust emissions, the ambient air number concentrations of particles coarser than 3 nm (N) was split into two components, N=N1+N2. This was done using a method based on the high correlation between black-carbon (BC) and number (N) concentrations which is typically observed in ambient air and is the result of vehicle exhaust emissions. The component N1 accounts for “those aerosol components directly emitted in the particle phase” and “those components nucleating immediately after emission”. The component N2 accounts for the new particle formation enhancements during the “dilution and cooling of the vehicle exhaust” and is also influenced by “in situ new particle formation in ambient air”. The contribution of N1 to N exhibits a maximum of 55% during the morning rush hours (07:00–08:00). The contribution of N2 to N exhibits a daily evolution with a broad maximum during daylight (as solar radiation intensity), while for about 7 h (11:00–17:00) the N2 contribution to N is about 70%. During some “afternoon N2 events”, N2 contributions exceeded 90%. Enhancements in the new particle formation processes may increase the N/BC concentrations ratio in one order of magnitude, from 4.82×10⁶ particles/ng BC to 47×10⁶ particles/ng BC and during some events up to 97×10⁶ particles/ng BC. The results show evidence of the high potential of the vehicle exhausts and of the urban atmosphere to trigger new particle formation if the ambient air conditions are favourable. The method used in this study is useful in assessing future changes in the number to BC relationship due to forthcoming regulations in the vehicle exhaust emissions.     

氮掺杂石墨烯量子点/细菌纤维素复合膜的制备及应用

以一水合柠檬酸和尿素为前驱体,采用一步水热法制备出具有良好水溶性和荧光性能的氮掺杂石墨烯量子点(N-GQDs)。以细菌纤维素(BC)为基体,采用原位浸渍的方法制备出了N-GQDs/BC复合膜。通过紫外-可见光谱仪、X射线衍射仪、傅里叶变换红外光谱仪、荧光光谱仪、透射电子显微镜对N-GQDs的结构和性能进行了表征,开发出一种绿色简单的荧光生物传感器并用于多巴胺(DA)的敏感检测。结果表明:N-GQDs/BC复合膜的荧光强度能有效地被DA猝灭,且DA浓度在0~100μmol/L的范围内呈现出很好的线性关系,检测限为3.3×10~(-8)mol/L;通过分析淬灭机制证明了荧光猝灭是由于电子转移导致的。     

Plasma Sphingosine-1-Phosphate Levels Are Associated with Progression of Estrogen Receptor-Positive Breast Cancer

Although numerous experiments revealed an essential role of a lipid mediator, sphingosine-1-phosphate (S1P), in breast cancer (BC) progression, the clinical significance of S1P remains unclear due to the difficulty of measuring lipids in patients. The aim of this study was to determine the plasma concentration of S1P in estrogen receptor (ER)-positive BC patients, as well as to investigate its clinical significance. We further explored the possibility of a treatment strategy targeting S1P in ER-positive BC patients by examining the effect of FTY720, a functional antagonist of S1P receptors, on hormone therapy-resistant cells. Plasma S1P levels were significantly higher in patients negative for progesterone receptor (PgR) expression than in those positive for expression (p = 0.003). Plasma S1P levels were also significantly higher in patients with larger tumor size (p = 0.012), lymph node metastasis (p = 0.014), and advanced cancer stage (p = 0.003), suggesting that higher levels of plasma S1P are associated with cancer progression. FTY720 suppressed the viability of not only wildtype MCF-7 cells, but also hormone therapy-resistant MCF-7 cells. Targeting S1P signaling in ER-positive BC appears to be a possible new treatment strategy, even for hormone therapy-resistant patients.     

Bacterial cellulose/PANi mat for Cr(VI) removal at acidic pH

Remediation of hexavalent chromium - Cr(VI) at acidic pH using polyaniline coated bacterial cellulose porous mat (BC/PANi) is presented and the possible mechanism is discussed. The efficacy of BC/PANi mats in remediation of Cr(VI) was studied by varying pH (pH 1, 2, 3, and 5) and initial Cr(VI) concentrations (250–1000 ppm) of the solution. The BC/PANi (50 mg) mat was able to completely reduce 2000 ppm Cr(VI) into Cr(III) in a 20 ml solution at pH ~ 1 in 24 h. An increasing chromium removal efficiency was observed with decreasing solution pH; reaching a maximum removal capacity of ~920 mg/g at pH 1. The proposed mechanism of negatively charged Cr(VI) ions removal by BC/PANi mat is adsorption and simultaneous reduction into Cr(III), followed by desorption of Cr(III) from the mat. The role of temperature and co-existing anions like sulphate, nitrate and chloride found in industrial sludge were also investigated for removal efficiency of Cr(VI) at acidic pH ~ 1. The adsorption kinetics of Cr(VI) on polyaniline surface followed a pseudo-second-order model with reduction of Cr(VI) into Cr(III) as rate-limiting step. The reduced Cr(III) from the media was further recovered by neutralizing the pH of the solution.     

维生素B1、维生素B2、维生素BC的极谱分析法

维生素B1、维生素B2、维生素BC混合物在pH为6.0的NaH2PO4-Na2HPO4缓冲溶液中均各自产生灵敏的极谱吸附波,且峰电位各不相同,依次为-1.5 V(vs.SCE)、-0.48 V(vs.SCE)、-0.90 V(vs.SCE)。且混合物浓度在1×10-4～6×10-2mol/L范围内维生素B1、维生素B2、维生素BC均与峰电流有良好的线性关系,线性系数分别为:0.9994、0.9960、0.9992,混合物的检出限为5×10-6mol/L。