帕立骨化醇对糖尿病肾病肾小管 上皮间充质转化的干预作用研究

目的 探讨帕立骨化醇对糖尿病肾病（DKD）肾小管上皮间充质转化（EMT）的作用及内在机制。方法 将24 只SD 大鼠按随机数字表法分为帕立骨化醇干预组（P 组）、糖尿病肾病组（D 组）和正常对照组（C 组）,每组各8 只。P 组和D 组大鼠腹腔注射链脲佐菌素65mg/kg建立糖尿病肾病模型,造模成功后第2天P 组腹腔注射帕立骨化醇（溶于丙二醇中）0.4滋g/kg,3 次/ 周,D 组予等体积丙二醇;C组仅予等体积丙二醇。4 周后测血、尿生化指标;进行肾脏病理学检查;免疫组化及Western blot 技术检测肾组织E- 钙粘蛋白（E-cadherin）、α- 平滑肌肌动蛋白（α-SMA）、纤连蛋白（FN）、转化生长因子-β1（TGF-β1）及Klotho 的表达,并进行指标间的相关性分析。结果 D组大鼠血清肌酐（Scr）、血尿素氮（BUN）及24 h尿蛋白水平均高于C 组,P 组均低于D 组（均P＜ 0.05）。C 组大鼠肾小管结构完整清晰,无明显病理改变;D 组可见肾小管间质局部炎症细胞浸润,肾小管上皮细胞脱落,小管扩张,基底膜断裂;P 组肾小管间质病理改变较D 组减轻。D 组大鼠肾组织E-cadherin 与Klotho表达低于C组,而P组高于D组（均P＜0.05）;与C 组比较,D 组大鼠肾组织α-SMA、FN 及TGF-β1 表达增加,而P 组表达均较D 组减少（均P＜0.05）。Klotho 表达与E-cadherin呈正相关（r=0.924,P＜0.05）,而与α-SMA、FN 及TGF-β1 均呈负相关（r=-0.806、-0.623、-0.856,均P＜0.05）。结论 帕立骨化醇可抑制糖尿病肾病大鼠肾小管上皮EMT,其作用可能与增加肾组织Klotho表达,同时减少TGF-β1合成相关。     

Fermionic-mode entanglement in non-Markovian environment

We evaluate the non-Markovian effects on the entanglement dynamics of a fermionic system interacting with two dissipative vacuum reservoirs. The exact solution of density matrix is derived by utilizing the Feynman–Vernon influence functional theory in the fermionic coherent state representation and the Grassmann calculus, which are valid for both the fermionic and bosonic baths, and their difference lies in the dependence of the parity of the initial states. The fermionic entanglement dynamics is presented by adding an additional restriction to the density matrix known as the superselection rules. Our analysis shows that the usual decoherence suppression schemes implemented in qubits systems can also be achieved for systems of identical fermions, and the initial state proves its importance in the evolution of fermionic entanglement. Our results provide a potential way to decoherence controlling of identical fermions.     

A new test on the conditional capital asset pricing model

Testing the validity of the conditional capital asset pricing model(CAPM) is a puzzle in the finance literatureLewellen and Nagel[14]find that the variation in betas and in the equity premium would have to be implausibly large to explain important asset-pricing anomaliesUnfortunately, they do not provide a rigorous test statisticBased on a simulation study, the method proposed in Lewellen and Nagel[14]tends to reject the null too frequently.We develop a new test procedure and derive its limiting distribution under the null hypothesis.Also, we provide a Bootstrap approach to the testing procedure to gain a good finite sample performanceBoth simulations and empirical studies show that our test is necessary for making correct inferences with the conditional CAPM.     

Molecular Hydrogels with Esterase-like Activity

The development of molecular hydrogels that can be applied for mimicking bioactive molecules attracts extensive interests of researchers in fields of self‐assembly. In this study, we reported on several molecular hydrogels based on naphthylacetic acid‐peptides containing L‐histidine formed by the heating‐cooling process. All hydrogels exhibited higher activity to hydrolyze 4‐nitrophenyl acetate (4‐NPA) than the free L‐histidine probably due the high density of L‐histidine residue at the surface of self‐assembled nanofibers. To calculate the 4‐NPA hydrolysis rates, the Michaelis‐Menten enzyme kinetics model was made. Among these gels, the gel of Nap‐GFFYGHY possesses the highest enzyme activity of making the ester bond cleavage, which is approximately 25 times higher than that of the control (free L‐histidine and Nap‐GFFYGYY). These results indicate that molecular hydrogels with self‐assembled nanofibers have great potential for the generation of self‐assembled multivalent materials.     

Effective synthesis of benzyl halides triggered by in situ prepared hypervalent halides

An effective approach for the direct benzylhalogenation with in situ generation of hypervalent halides has been developed.A variety of benzyl halides are produced in moderate to excellent yields(up to 99%) with high regioselectivities.UV absorption spectrum is employed to detect the formation of ferr-butyl hypoiodite.     

中药炮制机理研究的思路与方法——以咖啡豆的烘焙原理研究为例

中药炮制是中药学的特色和优势,也是最具我国自主知识产权的学科之一.中药炮制研究的核心是阐明中药炮制机理,这也是制约中药现代化的关键节点.目前大部分中药的炮制机理尚不明确,有待进行系统深入的研究.咖啡豆需要烘培后才可以制成饮料,这个高温烘培过程类似于中药的炮制过程.近年来,国内外专家对咖啡豆高温烘培过程化学成分变化及其机理进行了深入研究,各种新方法和新技术得到广泛应用,取得了系列研究成果,这些研究成果为中药炮制机理研究提供了多种新思路和新方法,也为中药炮制机理的研究和阐明提供了重要示范.     

Evolution of (GaAl) n Clusters and Chemisorptions of H2 on (GaAl) n Clusters

The growth behavior of (GaAl) _n (n = 1–12) and the chemisorptions of hydrogen on the ground state geometries have been studied with the three-parameter hybrid generalized gradient approximation due to Becke-Lee–Yang–Parr (B3LYP). The dissociation energy, the second-order energy differences, and the HOMO–LUMO gaps indicate that the magic numbers of the calculated (GaAl) _n clusters are n = 4 and 6. To my knowledge, this is the first time that a systematic study of chemisorptions of hydrogen on gallium aluminum clusters. The onefold top site of aluminum atom is identified to be the most favorable chemisorptions site for one hydrogen chemisorptions on most (GaAl) _n clusters. In general, dissociative chemisorptions of a hydrogen molecule on a top site of aluminum atom is found common for all sizes clusters considered here except for (GaAl) _n (n = 1–3) clusters. The stability of the (GaAl) _n H _m complexes shows that both large second-order difference and large fragmentation energies for (GaAl)₁₀H₂ and (GaAl)₁₁H₂ make these species behaving like magic clusters.     

Highly Selective Synthesis of Methyl 1-Phenyl-1-(9-hydro-)fullerenylacetate

Isomerically pure methyl 1-phenyl-1-(9-hydro-)fullerenylacetat is synthesized in 75% yield by the reaction of C₆₀ with the carbanions of methyl phenylacetate in C₆H₆/THF mixed solvent under a purified N₂ atmosphere at 20°C.     

Surface-Modified Sb2S3 Nanoparticles and Their Tribological Behaviors in Liquid Paraffin

Sb₂S₃ nanoparticles surface-modified with S-tetradecyl N, N-dihydroxyethyl dithiocarbamate (C₁₄DTC-Sb₂S₃) have been synthesized via extraction of Sb₂S₃ colloidal particles from ethylene glycol into toluene in the presence of C₁₄DTC. The obtained products were characterized by high-resolution transmission electron microscope (HRTEM) and Fourier transformation infrared (FTIR), and their tribological behaviors as an additive in liquid paraffin were investigated using a four-ball tribometer. The results show that C₁₄DTC-Sb₂S₃ nanoparticles can significantly improve the friction reduction, anti-wear, and load-carrying properties of base oils. The preliminary lubrication mechanism was discussed based on the SEM and XPS investigation of the rubbed surfaces.     

The importance of molecular complexity in the design of screening libraries

The one-dimensional model of Hann et al. (J Chem Inf Comput Sci 41(3):856–864) has been extended to include reverse binding and wrap-around interaction modes between the protein and ligand to explore the complete combinatorial matrix of molecular recognition. The cumulative distribution function of the Maxwell–Boltzmann distribution has been used to calculate the probability of measuring the sensitivity of the interactions as the asymptotic limits of the distribution better describe the behavior of the interactions under experimental conditions. Based on our model, we hypothesized that molecules of lower complexity are preferred for target based screening campaigns, while augmenting such a library with moieties of moderate complexities maybe better suited for phenotypic screens. The validity of the hypothesis has been assessed via the analysis of the hit rate profiles for four ChemBL datasets for enzymatic and phenotypic screens.