Study on thermal decomposition kinetics of azobenzene-4,4′-dicarboxylic acid by using compensation parameter method and nonlinear fitting evaluation

Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application in the future,the thermal stability of this substance during storage,transportation,and use will become quite important.Thus,in this work,the thermal decomposition behavior,thermal decomposition kinetics,and thermal hazard of ADCA were investigated.Experiments were conducted by using a SENSYS evo DSC device.A combination of differential iso-conversion method,compensation parameter method,and nonlinear fitting evaluation were also used to analyze thermal kinetics and mechanism of ADCA decomposition.The results show that when conversion rate α increases,the activation energies of ADCA's first and main decomposition peaks fall.The amount of heat released during decomposition varies between 182.46 and 231.16 J·g^(-1).The proposed kinetic equation is based on the Avrami-Erofeev model,which is consistent with the decomposition progress.Applying the Frank-Kamenetskii model,a calculated self-accelerating decomposition temperature of 287.0℃is obtained.

Oxygen-vacancy-rich MnO_(x)supported RuO_(x)for efficient base-free oxidation of 5-hydroxymethylfurfural and 5-methoxymethylfurfural to 2,5-furandicarboxylic acid

2,5-Furandicarboxylic acid(FDCA)is a promising biomass-derived polymeric monomer that serves as an attractive alternative to terephthalic acid derived from fossil resources.However,the green and efficient production of FDCA through the oxidation of 5-hydroxymethylfurfural(HMF)and its derivatives is still rudimentary under base-free conditions.In this work,oxygen-vacancy-rich Mn Oxwas prepared and displayed a strong adsorption and anchoring ability to Ru species that mainly exposed the(210)plane of RuO_(2),bringing about highly dispersed and active interfacial Ru-O-Mn structures.Experimental results and density functional theory calculations confirm that these above features greatly facilitate the adsorption/activation of oxygen and the dehydrogenation-oxidation of HMF/5-methoxymethylfurfural(MMF),which enables an efficient FDCA production under base-free and mild conditions.Notably,a desirable FDCA yield of 86.56%was still obtained from concentrated HMF(10 wt%)under base-free conditions over oxygen-vacancy-rich Mn Oxsupported Ru Ox(1.0 MPaO_(2),120℃,6 h).This work delineates a facile catalyst preparation strategy for HMF/MMF oxidation,and might open a new avenue for the green synthesis of FDCA under base-free conditions.

Transforming liquid flow fuel cells to controllable reactors for highlyefficient oxidation of 5-hydroxymethylfurfural to 2, 5-furandicarboxylic acid at low temperature

Highly-efficient oxidation of 5-hydroxymethylfurtural(HMF) to 2,5-furandicarboxylic acid(FDCA) at low temperature with air as the oxidant is still challenging.Herein,inspired by the respirato ry electron transport chain(ETC) of living cells mediated by electron carriers,we constructed artificial ETCs and transformed liquid flow fuel cells(LFFCs) to flexible reactors for efficient oxidation of HMF to produce FDCA under mild conditions.This LFFC reactor employed an electrodeposition modified nickel foam as an anode to promote HMF oxidation and(VO_(2))_(2)SO_(4) as a cathode electron carrier to facilitate the electron transfer to air.The reaction rate could be easily controlled by selecting the anode catalyst,adjusting the external loading and changing the cathodic electron carrier or oxidants.A maximal power density of 44.9 mW cm^(-2) at room temperature was achieved,while for FDCA production,short-circuit condition was preferred to achieve quick transfer of electrons.For a single batch operation with 0.1 M initial HMF,FDCA yield reached 97.1%.By fed-batch operation,FDCA concentration reached 144.5 g L^(-1) with a total yield of 96%.Ni^(2+)/Ni^(3+) redox couple was the active species mediating the electron transfer,while both experimental and DFT calculation results indicated that HMFCA pathway was the preferred reaction mechanism.

Traditional Chinese medicine Pien-Tze-Huang ameliorates LPS-induced sepsis through bile acid-mediated activation of TGR5-STAT3-A20 signalling

Pien Tze Huang(PZH),a class-1 nationally protected traditional Chinese medicine(TCM),has been used to treat liver diseases such as hepatitis;however,the effect of PZH on the progression of sepsis is unknown.Here,we reported that PZH attenuated lipopolysaccharide(LPS)-induced sepsis in mice and reduced LPS-induced production of proinflammatory cytokines in macrophages by inhibiting the activation of mitogen-activated protein kinase(MAPK)and nuclear factor-kappa B(NF-κB)signalling.Mechanistically,PZH stimulated signal transducer and activator of transcription 3(STAT3)phosphorylation to induce the expression of A20,which could inhibit the activation of NF-κB and MAPK signalling.Knockdown of the bile acid(BA)receptor G protein-coupled bile acid receptor 1(TGR5)in macrophages abolished the effects of PZH on STAT3 phosphorylation and A20 induction,as well as the LPS-induced inflammatory response,suggesting that BAs in PZH may mediate its anti-inflammatory effects by activating TGR5.Consistently,deprivation of BAs in PZH by cholestyramine resin reduced the effects of PZH on the expression of phosphorylated-STAT3 and A20,the activation of NF-κB and MAPK signalling,and the production of proinflammatory cytokines,whereas the addition of BAs to cholestyramine resin-treated PZH partially restored the inhibitory effects on the production of proinflammatory cytokines.Overall,our study identifies BAs as the effective components in PZH that activate TGR5-STAT3-A20 signalling to ameliorate LPS-induced sepsis.

Crystal Structure and Theoretical Studies of Tetrahytrate(1-H-1,2,4-triazole-3,5-dicarboxylicacid)nickel

A new compound, [Ni（Hdctrz）（H2O）4]（1, H3dctrz = 1-H-1,2,4-triazole-3,5-dicarboxylic acid）, has been successfully synthesized via slow evaporation. The structure of 1 was characterized by FT-IR, elemental analysis and single-crystal X-ray diffraction. Compound 1 crystallizes in monoclinic, space group P21/c with a = 6.871（1）, b = 11.468（1）, c = 12.178（1） A, b = 101.291（1）o, V = 941.01（16） A3, Z = 4, C4H9N3O8Ni, Mr = 285.85, Dc = 2.018 g·cm–3, m = 2.10 mm–1, F（000） = 584, GOOF = 1.025, the final R = 0.0515 and wR = 0.2125 for 1404 observed reflections（I 〉 2s（I））. The crystal structure is assembled by a slightly distorted {NiNO5} octahedral geometry and hydrogen bonds viz. N–H…O, O–H…O, C–O…π and π···π weak interactions. A rare π···π interaction from triazolate and carboxylate is affirmed through the molecular orbitals（MO） of three adjacent Ni CN molecules. The 3D Hirshfeld surface analysis was employed to gain additional insight into the interactions responsible for the packing of compound 1. Quantitative examination of 2D fingerprint plots revealed, amongst others, the dominating participation of O···H, N···H and π···π interactions in the molecular packing.

A Lanthanide-transition Metal Coordination Polymer:{[CuEu(Hbidc)_2(H_2O)_4]·H_2O}_n(H_3bidc=1H-benzimidazole-5,6-dicarboxylic Acid)

The title complex 1,{[CuEu（Hbidc）2（H2O）4]·H2O}n（H3bidc = 1H-benzimidazole-5,6-dicarboxylic acid）,has been solvothermally synthesized and structurally characterized by single-crystal X-ray diffraction.Complex 1 crystallizes in triclinic,space group P1,with a = 7.791（2）,b = 12.058（3）,c = 12.109（3）,α = 82.189（5）,β = 72.407（5）,γ = 89.184（4）°,V = 1073.7（5）3,C18H18CuEuN4O13,Mr = 713.86,Dc = 2.208 g/cm3,μ（MoKα） = 3.967 mm-1,F（000） = 700,GOOF = 0.950,Z = 2,the final R = 0.0531 and wR = 0.1068 for I 2σ（I）.Complex 1 possess a tape-like chain structure consisting of Eu2C8O4 and Cu2Eu2C18N4O4 metallic rings alternatively arranged and is the first 3d-4f heterometallic complex based on the 1H-ben-zimidazole-5,6-dicarboxylato ligand（Hbidc）.Plenty of hydrogen-bonding and π...π stacking interactions connect the 1D chains to construct a 3D supramolecular architecture.

Extraction Equilibria of Trimellitic and [ 1,1′-Biphenyl]-2,2′-dicarboxylic Acid with 1-Octanol, 50%TBP, and 10%TRPO in Kerosene

To explore the feasibility of extracting aromatic acid products from oxidizing coal, two aromatic acids, trimellitic and [1,1′-biphenyl]-2,2′-dicarboxylic acid, were selected as the solutes, and the extraction equilibrium of the acids were studied with 1-octanol, 50% tributyl phosphate （TBP） in kerosene, and 10% trialkylphosphine oxide （TRPO） in kerosene. The results showed that the degree of extraction of [1,1′-biphenyl]-2,2′-dicarboxylic acid was larger than that of trimellitic acid for all of the solvent, and the extraction capacity with TRPO is more effective than the one with TBP. The extraction behavior of aromatic polyacid is different from that of carboxylic acid, and the reactive extraction function of aromatic acids with TBP and TRPO is not as effective as that of carboxylic acid. 1-octanol could be used to remove [1,1′-biphenyl]-2,2′-dicarboxylic acid from the mixture of trimellitic acid and [1,1′-biphenyl]-2,2′-dicarboxylic acid. Because the weak hydrogen bond association exists between -OH in 1-octanol and -COOH in aromatic acid, the extractive selectivity of [ 1, 1′-biphenyl]-2,2′-dicarboxylic to trimellitic acid depends on the stoichiometric ratio.

Syntheses, Crystal Structures, and Properties of Two New Lanthanide Coordination Polymers Constructed from Benzimidazole-5,6-dicarboxylic Acid

Two lanthanide coordination polymers, {[Ln（Hbidc）（bidc）（H2 O）3]·3 H2 O}n（H3 bidc = benzimidazole-5,6-dicarboxylic acid, Ln = Eu（1）, Sm（2）） have been hydrothermally synthesized. Both compounds are isostructure and crystallize in the P21/c space group of monoclinic system. Complex 1: a = 11.087（6）, b = 8.972（5）, c = 23.064（13） ?, b = 95.027（5）o, V = 2285.4（2） ?3, Z = 4, Mr = 669.35, Dc = 1.945 g/cm3, F（000） = 1328, S = 1.044, μ = 2.827 mm-1, R = 0.0393 and wR = 0.0801 for 3458 observed reflections（I > 2s（I））. Complex 2: a = 11.087（6）, b = 8.972（5）, c = 23.064（13） ?, b = 95.027（5）°, V = 2285.4（2） ?3, Z = 4, Mr = 667.74, Dc = 1.941 g/cm3, F（000） = 1324, S = 1.071, μ = 2.652 mm-1, R = 0.0329 and wR = 0.0809 for 3744 observed reflections（I > 2s（I））. Complexes 1 and 2 have been determined by single-crystal X-ray diffraction analyses and further characterized by elemental analyses, IR spectroscopy, and thermogravimetric analyses（TGA）. The single-crystal X-ray diffraction analysis reveals that complexes 1 and 2 are the isostructural 1 D zigzag chain structures, which are further extended into a 3 D supramolecular structure through hydrogen bonds and p···p stacking interactions. Furthermore, the thermal stability, UV-vis absorption spectra and fluorescent properties of complexes 1 and 2 have been investigated and discussed in detail.

Synthesis and Structural Characterization of a New Cadmium(Ⅱ) Complex Bridged by Endo-norbornene-cis-5,6-dicarboxylic Acid

A polynuclear complex [Cd（endc）（H20）]n·nH2O （endc = endo-norbornene-cis- 5,6-dicarboxylate anion） has been synthesized by the hydrothermal reaction of cadmium nitrate tetrahydrate with endo-norbornene-cis-5,6-dicarboxylic acid in 1：1 molar ratio, and structurally characterized by single-crystal X-ray diffraction. It crystallizes in monoclinic, space group P21/c with α = 1.16471（7）, b = 0.95334（7）, c = 0.91109（9） nm, Z= 4, V= 1.01035（14） nm^3, D, = 2.160 g/cm^3,μ = 2.172 mm^-1, F（000） = 648, R = 0.0302 and wR = 0.0752. According to structural analysis, each Cd（II） ion is coordinated to six O atoms from three endc anions and one water molecule, giving a distorted octahedral geometry. Two- dimensional layer arrangement of the title complex is constructed from the bridging nature of endc. It is worth notice that adjacent two-dimensional layers are joined together to form a three-dimensional supramolecular framework via intermolecular hydrogen bonding interactions.

Structure and Photoluminescence of a 3D Coordination Polymer from Triazole and 2,6-Dimethylpyridine-3,5-dicarboxylic Acid

A new metal-organic coordination polymer [Zn2（trz）2（mpda）（H2O）]n（1, trz = 1,2,4-triazole, H2 mpda = 2,6-dimethylpyridine-3,5-dicarboxylic acid） was synthesized and characterized by single-crystal X-ray analyses. The crystal is of monoclinic system, space group P21/n, a = 9.619（3）, b = 8.920（3）, c = 22.159（6）, β = 96.897（4）°, V = 1887.3（9）3, Z = 4, Mr = 478.04, D3 c = 1.682 Mg/m, F（000） = 960, the final R = 0.0264 and wR = 0.0870（I 2σ（I））. Compound 1 consists of {[Zn4（trz）4]4＋}n layers, which are further connected by mpda2- to complete a three-dimensional structure. The title compound exhibits luminescence at λmax = 415 nm upon excitation at 364 nm.

A New 3D Layered-pillared Cobalt(II)-organic Framework Constructed by Imidazole-4,5-dicarboxylic Acid (H_3IDC) and 4,4'-Bipyridine (bipy)

A new 3D metal-organic framework of {[Co3（IDC）2（bipy）2（py）2]·7H2O}n （1） was obtained by the hydrothermal reaction of Co（NO3）2·6H2O, imidazole-4,5-dicarboxylic acid （H3IDC）, 4,4＇-bipyridine （bipy）, and pyridine （py）, and structurally characterized by elemental analysis, infrared spectroscopy, thermal gravimetric analysis, and single-crystal X-ray diffraction. X-ray diffraction crystal structural analysis reveals that it crystallizes in orthorhombic system, space group Pccn with a = 11.1040（3）, b = 19.8834（5）, c = 21.3025（5）, V = 4703.3（2）3, Mr = 1079.63, Z = 4, Dc = 1.525 Mg·m-3, F（000） = 2212, μ（CuKα） = 8.855 mm-1, the final R = 0.0331 and wR = 0.0713 for 2525 observed reflections with I ≥ 2σ（I）. In compound 1, each cobalt（II） ion is six-coordinated with a slightly distorted octahedral coordination geometry, and each μ3-IDC3- acts as a bridge to bond three neighboring Co（II） ions, leading to an infinite 2D network layer structure of [Co3（IDC）2]n with Kagomé lattice. The adjacent layers are further linked by μ2-bipy to form an infinite 3D layered-pillared framework architecture of [Co3（IDC）2（bipy）2（py）2]n.

Altered expression of metabotropic glutamate receptor 1 alpha after acute diffuse brain injury Effect of the competitive antagonist 1-aminoindan-1, 5-dicarboxylic acid

The diffuse brain injury model was conducted in Sprague-Dawley rats, according to Marmarou＇s free-fall attack. The water content in brain tissue, expression of metabotropic glutamate receptor la mRNA and protein were significantly increased after injury, reached a peak at 24 hours, and then gradually decreased. After treatment with the competitive antagonist of metabotropic glutamate receptor la, （RS）-l-aminoindan-1,5-dicarboxylic acid, the water content of brain tissues decreased between 12-72 hours after injury, and neurological behaviors improved at 2 weeks. These experimental findings suggest that the 1-aminoindan-1, 5-dicarboxylic acid may result in marked neuroprotection against diffuse brain injury.

Expression of metabotropic glutamate receptor 1a in a rat cortical neuronal model of in vitro mechanical injury and the effects of its competitive antagonist (RS)-1-aminoindan-1,5-dicarboxylic acid

The present study established a rat cortical neuronal model of in vitro mechanical injury. At 30 minutes after injury, the survival rate of the injured cortical neurons was decreased compared with normal neurons, and was gradually decreased with aggravated degree of injury. Reverse transcription-polymerase chain reaction results showed that at 1 hour after injury, there was increased expression of metabotropic glutamate receptor la in cortical neurons. Immunohistochemical staining results showed that at 30 minutes after injury, the number of metabotropic glutamate receptor 1a-positive cells increased compared with normal neurons. At 12 hours after injury, lactate dehydrogenase activity in the （RS）-l-aminoindan-1, 5-dicarboxylic acid （AIDA）-treated injury neurons was si[jnificantly decreased than that in the pure injury group. At 1 hour after injury, intracellular free Ca＂＋ concentration was markedly decreased in the AIDA-treated injury neurons than that in the pure injury neurons. These findings suggest that after mechanical injury to cortical neurons, metabotropic glutamate receptor la expression increased. The resulting increase in intracellular free Ca2＋ concentration was blocked by AIDA, indicating that AIDA exhibits neuroprotective effects after mechanical injury.

萝卜硫素通过调节ALOX5/NF-κB信号通路调控巨噬细胞糖酵解抑制糖尿病肾病进展

目的探讨萝卜硫素(SFN)调节花生四烯酸5-脂氧合酶基因(arachidonic acid 5-lipoxygenase,ALOX5)/核因子kappa B(NF-κB)信号通路调节巨噬细胞糖酵解对糖尿病肾病(DN)进展的影响。方法生物信息学分析SFN治疗DN的靶基因。使用30 mmol/L高葡萄糖(HG)处理人近端肾小管上皮细胞系(HK-2细胞)诱导体外DN模型。将HK-2细胞分为如下组:正常糖(NG)组、HG组、HG+SFN(3 mmol/L)组、HG+ALOX5组、HG+SFN(3 mmol/L)+ALOX5组、HG处理的巨噬细胞+HK-2细胞组、HG+SFN(3 mmol/L)处理的巨噬细胞+HK-2细胞组、HG+ALOX5转染处理的巨噬细胞+HK-2细胞组、HG+SFN(3 mmol/L)+ALOX5转染处理的巨噬细胞+HK-2细胞组。CCK-8检测细胞活力,原位末端脱氧核苷酸转移酶标记(TUNEL)法检测细胞凋亡;葡萄糖和乳酸试剂盒检测各组细胞中葡萄糖和乳酸水平;Western blot检测各组细胞中ALOX5、NF-κB以及糖酵解相关蛋白己糖激酶-2(HK2)、丙酮酸激酶M2(PKM2)、葡萄糖转运蛋白1(GLUT1)的表达;使用链脲佐菌素(STZ)构建DN小鼠模型,DN小鼠给与SFN(0.5 mg/kg)治疗;检测小鼠各项生化指标,HE染色检测肾组织病理变化;Western blot检测小鼠肾脏巨噬细胞中糖酵解相关蛋白己糖激酶-2(HK2)、丙酮酸激酶M2(PKM2)、葡萄糖转运蛋白1(GLUT1)的表达。结果生物信息学分析结果显示ALOX5是SFN治疗DN的靶基因。与HG组相比,SFN处理增强HK-2细胞活力并抑制细胞凋亡(P<0.05);同时,SFN处理抑制HG诱导的巨噬细胞糖酵解相关蛋白的表达,减弱巨噬细胞介导的HK-2细胞损伤(P<0.05);Western blot结果表明SFN抑制ALOX5和NF-κB的表达(P<0.05);小鼠实验结果显示,SFN治疗改善DN小鼠肾功能和肾组织病理学改变,抑制肾组织中巨噬细胞糖酵解相关蛋白的表达(P<0.05)。结论SFN通过抑制ALOX5/NF-κB信号通路抑制巨噬细胞糖酵解从而改善DN进展。

龟羚帕安丸对帕金森病大鼠血清NSE、Cys-C、5-HT、5-HIAA及NE水平的影响

目的观察龟羚帕安丸对帕金森病(Parkinson’s disease,PD)大鼠血清神经元特异性烯醇化酶(Neuron-specific enolase,NSE)、胱抑素C(Cystatin C,Cys-C)、5-羟色胺(5-Hydroxytryptamine,5-HT)、5-羟基吲哚乙酸(5-Hydroxyindoleacetic acid,5-HIAA)及去甲肾上腺素(Norepinephrine,NE)水平的影响。方法采用6-羟基多巴胺(6-OHDA)立体定向注射法制作PD大鼠模型,造模成功的PD大鼠随机分为模型组,西药组,中药高、中、低剂量组,中西药合用组,每组15只,另设假手术组15只。模型组及假手术组给予等容积生理盐水灌胃,其余组给予相应药物灌胃,连续给药28 d。大鼠腹主动脉取血,用酶联免疫吸附测定法(Enzyme linked immunosorbent assay,ELISA)检测各组大鼠血清NSE、Cys-C、5-HT、5-HIAA及NE的水平。结果模型组大鼠血清NSE及Cys-C水平均明显升高,血清5-HT、5-HIAA及NE水平均明显降低;中药各剂量组、中西药合用组、西药组血清NSE及Cys-C水平均明显降低,5-HT、5-HIAA及NE水平均明显升高。结论龟羚帕安丸具有明显神经保护作用,作用机制与降低NSE及Cys-C水平,增加5-HT、5-HIAA及NE水平,降低脑实质损伤、神经炎症损伤及提高单胺类神经递质有关。

非小细胞肺癌组织中lncRNA GAS5、LHPP表达与上皮间质化相关性及临床意义

目的探讨非小细胞肺癌(NSCLC)患者癌组织中长链非编码核糖核酸生长抑制特异性基因5(lncRNA GAS5)、磷酸赖氨酸磷酸组氨酸无机焦磷酸盐磷酸酶(LHPP)表达与上皮间质化(EMT)相关性及临床意义。方法收集2018年6月至2020年1月在河北北方学院附属第一医院行手术切除的NSCLC 90例患者的癌组织及癌旁组织,采用实时荧光定量聚合酶链反应检测lncRNA GAS5、LHPP和EMT相关蛋白[E-钙黏蛋白(E-Cad)、N-钙黏蛋白(N-Cad)和波形蛋白(VIM)]表达。分析NSCLC患者癌组织中lncRNA GAS5、LHPP mRNA与临床病理特征的关系,并通过Pearson相关性分析NSCLC患者癌组织中lncRNA GAS5、LHPP mRNA与EMT相关蛋白表达的相关性。采用Kaplan-Meier法绘制不同lncRNA GAS5、LHPP mRNA表达的NSCLC患者生存曲线,多因素Cox回归分析NSCLC患者预后的影响因素。结果NSCLC患者癌组织中lncRNA GAS5、LHPP mRNA、E-Cad mRNA表达低于癌旁组织,N-Cad mRNA、VIM mRNA表达高于癌旁组织,差异有统计学意义(P<0.05)。Pearson相关性分析显示,NSCLC患者癌组织中lncRNA GAS5与E-Cad mRNA表达呈正相关(r=0.724,P<0.001),与N-Cad mRNA、VIM mRNA表达呈负相关(r=-0.699、-0.689,P<0.001);lncRNA GAS5与LHPP mRNA表达呈正相关(r=0.651,P<0.001)。不同分化程度、肿瘤TNM分期、淋巴结转移的NSCLC患者癌组织中lncRNA GAS5、LHPP mRNA表达比较差异有统计学意义(P<0.05)。Kaplan-Meier生存曲线分析显示,lncRNA GAS5高表达组的3年总生存率[68.18%(30/44)]高于lncRNA GAS5低表达组的3年总生存率[36.96%(17/46)];LHPP mRNA高表达组的3年总生存率[67.39%(31/46)]高于LHPP mRNA低表达组的3年总生存率[36.36%(16/44)],差异有统计学意义(χ^(2)=10.274、10.322,P<0.05)。低分化、肿瘤TNM分期Ⅲ期、有淋巴结转移为NSCLC患者死亡的独立危险因素,lncRNA GAS5≥1.32、LHPP mRNA≥1.12为独立保护因素(P<0.05)。结论NSCLC患者癌组织中lncRNA GAS5、LHPP mRNA低表达,与EMT相关蛋白表达、分化程度、肿瘤TNM分期、淋巴结转移和预后有关,可能成为NSCLC诊治的新靶点。

果糖酸处理HZSM-5己烯芳构化催化剂的结构及性能

为提高HZSM-5己烯芳构化催化剂的BTX(苯、甲苯、二甲苯)选择性和寿命,利用果糖酸对HZSM-5进行处理(F-HZS),并与磷酸和硝酸处理的HZSM-5(P-HZS和N-HZS)进行对比,采用XRD、XRF、N_(2)吸附-脱附、NH_(3)-TPD、Py-FTIR等方法对催化剂结构进行表征,考察了催化剂己烯芳构化的催化性能。实验结果表明,酸处理后催化剂的MFI结构保留完整,且出现了介孔结构。催化剂的孔体积、硅铝比及B酸量和L酸量比值(B/L)增加,但酸量及酸强度下降,F-HZS的B/L最高,BTX选择性和寿命也明显高于P-HZS和N-HZS。在0.2 MPa、405℃,质量空速2 h-1条件下,F-HZS的BTX选择性为61.34%,寿命为60 h。

脂肪酸结合蛋白5结合Vimentin蛋白在肝癌中的作用机制

目的 筛选和验证与脂肪酸结合蛋白5(FABP5)结合的互作蛋白,同时研究FABP5与候选蛋白的调控关系,进一步探讨FABP5在肝癌中的作用机制。方法 采用免疫沉淀联合串联质谱分析方法(IP-MS)筛选出与FABP5相互结合的蛋白;通过免疫共沉淀实验(Co-IP)从外源性和内源性层面验证FABP5与候选互作蛋白的结合关系;利用RT-qPCR、Western blot和免疫荧光法观察敲低FABP5对肝癌细胞中波形蛋白(Vimentin)转录和翻译水平的影响;通过鬼笔环肽染色实验观察过表达FABP5对肝癌细胞骨架的影响。结果 IP-MS鉴定出336个与FABP5相互结合的潜在靶蛋白,结合文献,挑选出5个与肿瘤相关的候选蛋白,分别为PRDX1、PRSS3、PKM、HSP90AA1和Vimentin蛋白。通过外源性和内源性Co-IP实验证实FABP5与Vimentin蛋白存在结合关系。敲低FABP5对肝癌细胞中Vimentin mRNA的表达没有显著作用,但可抑制Vimentin蛋白的表达,而过表达FABP5会影响肝癌细胞的骨架。结论 FABP5促进肝癌细胞的迁移和侵袭,其机制可能与FABP5结合调控Vimentin蛋白和影响细胞骨架重塑有关,有望成为抗肝癌的潜在靶点,为肝癌的治疗提供新的思路。

5-氨基酮戊酸-光动力联合小剂量异维A酸治疗玫瑰痤疮的疗效及安全性研究

目的:探讨5-氨基酮戊酸(ALA)-光动力(PDT)联合小剂量异维A酸治疗玫瑰痤疮(AR)的疗效及安全性。方法:选取2022年1月至2023年1月新疆医科大学第二附属医院收治的AR患者86例,采用随机数字表法分为联合组和对照组,各43例。对照组患者采用小剂量异维A酸治疗,联合组患者采用ALA-PDT联合小剂量异维A酸治疗。比较两组患者的临床疗效,治疗前后皮肤红斑指数(EI)、痤疮特异性生活质量量表(Acne-QOL)评分、皮肤生理功能[经皮水分流失量(TEWL)、角质层含水量和pH]、角质层完整性指标(丝氨酸蛋白酶活性、粘脱蛋白质含量)及不良反应发生情况。结果:联合组患者的总有效率为95.35%(41/43),较对照组的79.07%(34/43)更高,差异有统计学意义(P<0.05)。治疗后,联合组患者的EI低于对照组,Acne-QOL评分高于对照组;联合组患者的TEWL、pH低于对照组,角质层含水量高于对照组;联合组患者的丝氨酸蛋白酶活性、粘脱蛋白质含量低于对照组,上述差异均有统计学意义(P<0.05)。联合组、对照组患者不良反应发生率分别为9.30%(4/43)、11.63%(5/43),差异无统计学意义(P>0.05)。结论:ALA-PDT联合小剂量异维A酸治疗AR,可修复患者皮肤屏障功能,改善EI,提高生活质量,疗效显著,安全性高。

2型糖尿病伴干眼症病人血清和泪液分泌型卷曲相关蛋白5、脂肪酸结合蛋白4水平与病情严重程度的相关性

目的分析分泌型卷曲相关蛋白5(SFRP-5)、脂肪酸结合蛋白4(FABP4)在2型糖尿病(T2DM)伴干眼症病人血清和泪液中的表达及其与病情严重程度的相关性。方法选取2020年12月至2021年12月唐山市眼科医院收治的T2DM病人145例,其中单纯T2DM病人84例168眼(T2DM组),伴干眼症病人61例122眼(T2DM伴干眼症组),另选取同期该院体检健康者50例100眼作为对照组。T2DM伴干眼症病人又分为轻度组(29例)、中度组(17例)、重度组(15例)。利用酶联免疫吸附法测定所有受试者血清和泪液中SFRP-5、FABP4水平;相关性分析采用Pearson法或Spearman法;logistic回归分析影响T2DM病人干眼症发生的因素。结果T2DM伴干眼症组、T2DM组血清和泪液SFRP-5水平均低于对照组(106.09±8.37、135.72±9.26比158.34±9.45,28.85±5.13、58.27±6.14比45.18±5.92),T2DM伴干眼症组低于T2DM组(P<0.05);T2DM伴干眼症组、T2DM组血清和泪液FABP4水平均高于对照组(70.63±6.59、58.27±6.14比45.18±5.92,15.91±3.76、10.28±3.58比7.72±3.29),T2DM伴干眼症组高于T2DM组(P<0.05)。重度组、中度组血清和泪液SFRP-5水平(68.29±7.15、95.54±8.34比131.82±9.02,12.83±4.62、24.72±5.49比39.56±5.18)、泪膜破裂时间(BUT)、泪液分泌试验(SIT)低于轻度组,重度组低于中度组(P<0.05);重度组、中度组血清和泪液FABP4水平(84.56±6.83、73.18±6.94比61.93±6.27,25.64±4.19、17.15±3.86比10.16±3.47)及眼表疾病指数量表(OSDI)积分高于轻度组,重度组高于中度组(P<0.05)。T2DM伴干眼症病人血清与泪液SFRP-5水平呈正相关,血清与泪液FABP4水平也呈正相关(P<0.05)。T2DM伴干眼症病人血清和泪液SFRP-5水平与OSDI积分均呈负相关,与BUT、SIT均呈正相关(P<0.05);血清和泪液FABP4水平与OSDI积分均呈正相关,与BUT、SIT均呈负相关(P<0.05)。血清和泪液SFRP-5水平是影响T2DM病人干眼症发生的独立保护因素,而血清和泪液FABP4水平是独立危险因素(P<0.05)。结论SFRP-5在T2DM伴干眼症病人血清和泪液中均低表达,FABP4均高表达,二者与病情严重程度密切相关。