重组人淋巴细胞活化基因-3蛋白胞外段的真核表达及鉴定

目的真核表达重组人淋巴细胞活化基因-3(lymphocyte activation gene-3,LAG-3)蛋白胞外段,并进行鉴定。方法用植物血球凝集素(phytohaemagg lutinin,PHA)刺激Jurkat细胞,流式细胞术检测Jurkat细胞中LAG-3蛋白的表达;提取Jurkat细胞总mRNA,RT-PCR法扩增人LAG-3蛋白胞外段基因片段,同时在蛋白C-末端引入His标签,将其克隆入载体pcDNA3. 1+,构建重组质粒,转染Expi293F真核细胞,当细胞活率低于50%时收获细胞上清,经镍柱亲合层析纯化。纯化产物进行4%~20%SDS-PAGE、HPLC及Western blot分析,BCA法测定浓度。结果经菌液PCR、双酶切及测序鉴定,表明质粒构建正确。重组表达蛋白的相对分子质量约60 000,纯化后纯度达95%以上,与鼠抗LAG-3单克隆抗体可发生特异性结合,浓度为2. 4 mg/mL。结论成功构建了重组真核表达质粒LAG-3/pcDNA3. 1+,并于Expi293F细胞中表达,纯化获得了纯度较高的LAG-3蛋白,为后期LAG-3蛋白的相关研究及其单抗的制备奠定了基础。     

彩色纳米碳酸钙的研制

以纳米碳酸钙中试装置为平台,通过控温碳化、加热湿法染色、加热湿法改性和分散处理,制得了具有良好一次粒子形态的彩色纳米碳酸钙产品。激光粒度仪测试表明,彩色纳米碳酸钙产品的D₅₀约为350 nm,具有粒度分布均匀、分布范围窄等特点。产品在空气中长期放置不氧化、不褪色,说明具有良好的化学稳定性。亲水性实验表明,彩色纳米碳酸钙产品在水中长时间放置、反复搅拌,仍然不沉降、不掉色,说明染色和活化都是牢固的。以酸性媒染蓝黑B染料和硬酯酸为例,分析了纳米碳酸钙的湿法染色和湿法活化机理,并且探讨了硬酯酸分子、染色剂分子和碳酸钙颗粒之间的化学交联作用。     

Investigation of flow parameters of Reiner–Philippoff nanofluid flow with higher-order slip properties,activation energy,and bioconvection by artificial neural networks

In this study, the flow parameters of Reiner–Philippoff nanofluid flow with high-order slip properties, activation energy, and bioconvection have been analyzed using artificial neural networks (ANNs). Local Nusselt number (LNN), local Sherwood number (LSN), and motile density number (MDN) are considered as flow parameters. Numerical values have been obtained by numerical methods using flow equations. To estimate the flow parameters, three different ANN models have been designed. The Levenberg–Marquardt training algorithm is used in multilayer perceptron network models with 10 neurons in the hidden layers. In all, 70% of the data set has been used for training the models, 15% for validation, and 15% for testing. The performance analysis of the network models has been made by calculating the determined performance parameters. The R values for the LNN, LSN, and MDN parameters have been calculated as 0.99261, 0.98769, and 0.99102, respectively, and the average deviation values are −0.65%, 0.06%, and −0.11%, respectively. The attained outcomes showed that the ANNs can predict the LNN, LSN, and MDN, which are the flow parameters of the Reiner–Philippoff nanofluid flow, with high accuracy.     

Nonoxidative methane activation,coupling, and conversion to ethane,ethylene, and hydrogen over Fe/HZSM‐5, Mo/HZSM‐5, and Fe–Mo/HZSM‐5 catalysts in packed bed reactor

A high abundance of methane and its relatively low price make it an attractive raw feedstock for the production of ethylene, which is in the consumer demand in recent years. Direct catalytic nonoxidative conversion is interesting, because it could be utilized on natural gas well sites. Monometallic and bimetallic Fe and Mo catalysts were prepared for the purpose of the coupling to ethane and ethene. Three supported materials were synthesized with the following loading of metal: 2.5‐wt% Fe, 5.0‐wt% Fe, and 2.5‐wt% Mo on HZSM‐5. Process' chemical reactions were also catalyzed with a constant 2.5‐wt% Mo/HZSM‐5, which had different amounts of Fe, namely, 0.5, 1.0, and 2.5 wt%. Fourier transform infrared (FTIR), N₂ adsorption/desorption, NH₃ temperature‐programmed desorption (TPD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X‐ray diffraction (XRD) were applied for characterization. Coke, accumulated on spent solids, was determined by thermogravimetric analysis (TGA). Activity was evaluated in quartz‐packed bed reactor. All surfaces suffered from deactivation due to carbon formation. The addition of Fe to Mo increased CH₄ reacted. The highest selectivity for alkenes was achieved over 1.0‐wt% Fe to 2.5‐wt% Mo/HZSM‐5. At the peak of performance, the C‐based reactivity was 52% for olefins and 2% for alkanes. Stability was accomplished over 2.5‐wt% Fe/HZSM‐5, where the rate of C₂ synthesis was comparatively stable for 20 hours of the time on stream. The selective C‐basis yield for C₂H₄ and C₂H₆ was 36% and 23%, respectively. The lowest measured quantity of (carbonaceous) by‐products was deposited on 2.5‐wt% Fe/HZSM‐5 after 26 hours. Propylene was detected very limitedly.     

Preparation of composite cathode material by using the extracted lead (Pb) of waste lead acid battery for LT-SOFC

The extraction of Pb from the waste lead acid batteries offers the conservation of energy resources and reduction of pollution load in the environment. The recycling of waste lead acid batteries than discarding by conventional methods is the best way. In the present studies, for LT-SOFC, three composite cathode materials (Pb_0.1Fe_0.4Co_0.5O_4-δ, Pb_0.2Fe_0.3Co_0.5O_4-δ and Pb_0.3Fe_0.2Co_0.5O_4-δ) were produced by extracting Pb from the waste lead acid batteries, cobalt nitrate [Co(NO₃)₃.6H₂O] and iron nitrate [Fe(NO₃)₃.9H₂O] using standard solid state reaction method. Thermal stability, morphological and structural characteristics were studied by TGA, SEM and XRD analyses. FTIR spectra were used to investigate the types of metal oxide bonding in the prepared ceramic composite cathode materials. Fuel cell testing and DC four probes were used to investigate electrochemical properties. The measurement of average crystalline size of the composites was found to be in the range of 12–37 nm.Scanning electron microscopy (SEM) images showed that composite materials are porous and suitable to diffuse the gases. The maximum conductivities of 1.6 Scm^?1, 2.05 Scm^?1 and 2.6 Scm^?1 have been obtained for Pb_0.1Fe_0.4Co_0.5O_4-δ, Pb_0.2Fe_0.3Co_0.5O_4-δ and Pb_0.3Fe_0.2Co_0.5O_4-δ, respectively. At 600 °C, the high OCV (0.95V) and the maximum power density (439 mW/cm²) have been achieved using hydrogen as the fuel. Lower value of activation energy (0.36ev) of Pb_0.3Fe_0.2Co_0.5O_4-δ confirms that it is the efficient material to convert electrochemically hydrogen fuel into valuable electricity.     

Numerical and sensitivity analysis of MHD bioconvective slip flow of nanomaterial with binary chemical reaction and Newtonian heating

The impact of Stefan blowing on the MHD bioconvective slip flow of a nanofluid towards a sheet is explored using numerical and statistical tools. The governing partial differential equations are nondimensionalized and converted to similarity equations using apposite transformations. These transformed equations are solved using the Runge–Kutta–Fehlberg method with the shooting technique. Graphical visualizations are used to scrutinize the effect of the controlling parameters on the flow profiles, skin friction coefficient, local Nusselt, and Sherwood number. Moreover, the sensitivities of the reduced Sherwood and Nusselt number to the input variables of interest are explored by adopting the response surface methodology. The outcomes of the limiting cases are emphatically in corroboration with the outcomes from preceding research. It is found that the heat transfer rate has a positive sensitivity towards the haphazard motion of the nanoparticles and a negative sensitivity towards the thermomigration. The thermal field is enhanced by the Stefan blowing aspect. Moreover, the fluid velocity can be controlled by the applied magnetic field.     

Reactivity of industrial wastes as measured through ICP-OES: A case study on siliceous Indian biomass ash

An untapped source of amorphous SiO₂, industrially generated Indian biomass ash (SA)—90% amorphous, with composition of ~60% SiO₂ and ~20% unburnt carbon—can be used to produce cementitious and alkali-activated binders. This study reports dissolution of amorphous Si from SA in 0.5 mol/L and 1 mol/L aqueous NaOH, with and without added Ca(OH)₂, at SA:Ca(OH)₂ wt% ratios of 100:0, 87.5:12.5, and 82.5:17.5. Monitoring of elemental dissolution and subsequent/simultaneous product uptake by ICP-OES offers an effective process for evaluating utility of industrial wastes in binder-based systems. After 28 days in solution, up to 68% of total Si is dissolved from SA in 1 mol/L NaOH, with values as much as 38% lower in the presence of Ca(OH)₂, due to the formation of tobermorite-like C-S-H. FTIR, ²⁹Si MAS-NMR, and XRD are used to characterize solid reaction products and observe reaction progress. Product chemistries calculated from ICP-OES results and verified by selective dissolution in EDTA/NaOH—namely, Ca/Si of 0.6-1 and Na adsorption of 1-2 mmol/g—are found to be consistent with those indicated by aforementioned techniques. This indicates the efficacy of ICP-OES in estimating product chemistry via such a methodology.     

Role of Polyinosinic:Polycytidylic Acid-Induced Maternal Immune Activation and Subsequent Immune Challenge in the Behaviour and Microglial Cell Trajectory in Adult Offspring: A Study of the Neurodevelopmental Model of Schizophrenia

Multiple lines of evidence support the pathogenic role of maternal immune activation (MIA) in the occurrence of the schizophrenia-like disturbances in offspring. While in the brain the homeostatic role of neuron-microglia protein systems is well documented, the participation of the CX3CL1-CX3CR1 and CD200-CD200R dyads in the adverse impact of MIA often goes under-recognized. Therefore, in the present study, we examined the effect of MIA induced by polyinosinic:polycytidylic acid (Poly I:C) on the CX3CL1-CX3CR1 and CD200-CD200R axes, microglial trajectory (MhcII, Cd40, iNos, Il-1β, Tnf-α, Il-6, Arg1, Igf-1, Tgf-β and Il-4), and schizophrenia-like behaviour in adult male offspring of Sprague-Dawley rats. Additionally, according to the “two-hit” hypothesis of schizophrenia, we evaluated the influence of acute challenge with Poly I:C in adult prenatally MIA-exposed animals on the above parameters. In the present study, MIA evoked by Poly I:C injection in the late period of gestation led to the appearance of schizophrenia-like disturbances in adult offspring. Our results revealed the deficits manifested as a diminished number of aggressive interactions, presence of depressive-like episodes, and increase of exploratory activity, as well as a dichotomy in the sensorimotor gating in the prepulse inhibition (PPI) test expressed as two behavioural phenotypes (MIA_PPI-low and MIA_PPI-high). Furthermore, in the offspring rats subjected to a prenatal challenge (i.e., MIA) we noticed the lack of modulation of behavioural changes after the additional acute immune stimulus (Poly I:C) in adulthood. The important finding reported in this article is that MIA affects the expression and levels of the neuron-microglia proteins in the frontal cortex and hippocampus of adult offspring. We found that the changes in the CX3CL1-CX3CR1 axis could affect microglial trajectory, including decreased hippocampal mRNA level of MhcII and elevated cortical expression of Igf-1 in the MIA_PPI-high animals and/or could cause the up-regulation of an inflammatory response (Il-6, Tnf-α, iNos) after the “second hit” in both examined brain regions and, at least in part, might differentiate behavioural disturbances in adult offspring. Consequently, the future effort to identify the biological background of these interactions in the Poly I:C-induced MIA model in Sprague-Dawley rats is desirable to unequivocally clarify this issue.     

Electrochemical activation construction of LaCo1-x-yNixFeyO3 promoted by optimized lattice Ni doping toward water oxidation

Iron sites with high intrinsic activity for oxygen evolution reaction (OER) can effectively enhanced the performance of perovskite oxide as electrocatalyst for water electrolysis. However, doping of iron in perovskite LaCoO₃ remains a challenge owing the strong Co–O bond and robust structure of LaCoO₃. Herein, the lattice doping of Ni in LaCoO₃ has been adopted to promote the interaction between iron ions and Co site in LaCoO₃. Firstly, molten salt of Ni(NO₃)₂ provides free-moving Ni ions to substitute Co sites in the lattice of LaCoO₃ forming LaCo_1-xNi_xO₃ at the optimized Ni doping condition. Then, iron ions can easily be absorbed to LaCo_1-xNi_xO₃ due to the strong interaction between Ni and Fe by electrochemical activation at room temperature. The prepared LaCo_1-x-yNi_xFe_yO₃ nanoparticles keep the coarse surface for maximizing the exposure of active sites. The high-valence Co and oxygen vacancy from LaCo_1-x-yNi_xFe_yO₃ contribute to the better intrinsic activity for OER, demonstrating the overpotential of ?₁₀ of approximately 315 mV and good stability. The strategy of by introducing the lattice doping of other metal ion can realize the facile and effective construction of iron doped perovskite oxide for water oxidation.     

四氢姜黄素经PI3K/Akt信号通路对人血小板活化和聚集的调控作用

目的：探讨姜黄素的主要肠道代谢物四氢姜黄素（tetrahydrocurcumin，THC）对血小板活化和聚集的影响及其可能的分子机制。方法：在体外实验中，用不同浓度的THC（0、0.5、1、10 μmol/L）提前与健康人纯化血小板共同孵育40 min，然后加入凝血酶激活血小板2 min，用流式细胞术测定血小板表面CD62P和CD63的表达量，用酶联免疫吸附法测定血小板释放血小板因子-4（platelet factor-4，PF4）和趋化因子配体-5（chemokine ligand 5，CCL5）水平，用血小板聚集仪检测血小板释放ATP水平和血小板最大聚集率，用Western blot蛋白免疫印迹法检测血小板磷酸肌醇-3-激酶（phosphoinositide 3-kinase，PI3K）和Akt蛋白的磷酸化水平。结果：与模型组（血小板悬液中加入0.05%二甲基亚砜）相比，THC能抑制凝血酶诱导的血小板表面CD62P和CD63的表达，抑制PF4、CCL5和ATP的释放，降低血小板最大聚集率，下调PI3K和Akt蛋白的磷酸化水平，且呈浓度依赖效应，其中10 μmol/L的浓度下作用效果显著（P＜0.01、P＜0.001）。PI3K的特异性激动剂740 Y-P可部分逆转THC对PF4和CCL5释放和血小板聚集的抑制作用（P＜0.05、P＜0.01）。结论：THC具有显著抑制血小板活化和聚集的作用，其机制可能是THC可下调PI3K/Akt介导的信号通路。