Angiotensin-converting enzyme 2 alleviates liver fibrosis through the renin-angiotensin system

The present letter to the editor is related to the study titled‘Angiotensin-converting enzyme 2 improves liver fibrosis in mice by regulating autophagy of hepatic stellate cells’.Angiotensin-converting enzyme 2 can alleviate liver fibrosis by regulating autophagy of hepatic stellate cells and affecting the renin-angiotensin system.

非水四乙基氯化铵体系中电溶解耦合铪醇盐合成的电化学机理与动力学

作为一种具有广泛应用前景的高效电合成技术,耦合电溶解的铪醇盐合成(EHS)基于铪溶解/乙醇脱氢的同时非均相反应以及溶液中Hf^(4+)阳离子和烷氧阴离子的自发结合反应。为了阐明EHS过程的机制和动力学,通过电化学测试、扫描电镜、气相色谱和微观动力学模拟等手段,探究阳极铪溶解和阴极乙醇脱氢的电化学行为。结果表明,优选的支持电解质四乙基氯化铵(Et_(4)NCl)展现了钝化膜击穿与铪溶解协同的剧烈点蚀机制以及两段脱氢机制。为量化钝化膜击穿和铪点蚀的动力学参数,提取与钝化速率、钝化膜击穿敏感性和点蚀速率相关的3个指标,并通过建立微观动力学模型评估基于Et_(4)NCl体系的EHS工艺,其电能消耗为1.53~1.83 k W·h/kg Hf(OC_(2)H_(5))_(4)。

Effects of permissive hypocaloric vs standard enteral feeding on gastrointestinal function and outcomes in sepsis

BACKGROUND Intestinal mucosal barrier injury and gastrointestinal dysfunction are important causes of sepsis.However,few studies have investigated the effects of enteral underfeeding on gastrointestinal function in sepsis.Moreover,no consensus on goal enteral caloric intake has been reached in sepsis.AIM To investigate the effects of different goal caloric requirements of enteral nutrition on the gastrointestinal function and outcomes in the acute phase of sepsis.METHODS Patients were randomly assigned to receive 30%(defined as group A),60%(group B),or 100%(group C)of goal caloric requirements of enteral nutrition in this prospective pilot clinical trial.The acute gastrointestinal injury(AGI)grades,incidence of feeding intolerance(FI),daily caloric intake,nutritional and inflammatory markers,and biomarkers of mucosal barrier function were collected during the first 7 d of enteral feeding.The clinical severity and outcome variables were also recorded.RESULTS A total of 54 septic patients were enrolled.The days to goal calorie of group C(2.55±0.82)were significantly longer than those of group A(3.50±1.51;P=0.046)or B(4.85±1.68;P<0.001).The FI incidence of group C(16.5%)was higher than that of group A(5.0%)or B(8.7%)(P=0.009).No difference in the incidence of FI symptoms was found between groups A and B.The serum levels of barrier function biomarkers of group B were significantly lower than those of group A(P<0.05)on the 7th day of feeding.The prealbumin and IL-6 levels of group A were lower than those of group B(P<0.05)on the 7th day of feeding.No significant differences in the clinical outcome variables or 28-d mortality were found among the three groups.CONCLUSION Early moderate enteral underfeeding(60%of goal requirements)could improve the intestinal barrier function and nutritional and inflammatory status without increasing the incidence of FI symptoms in sepsis.However,further large-scale prospective clinical trials and animal studies are required to test our findings.Moreover,the effects of different protein intake on gastrointestinal function and outcomes should also be investigated in future work.

Reductive smelting of spent lead–acid battery colloid sludge in a molten Na_2CO_3 salt

Lead extraction from spent lead–acid battery paste in a molten Na2CO3 salt containing Zn O as a sulfur-fixing agent was studied. Some influencing factors, including smelting temperature, reaction time, Zn O and salt dosages, were investigated in detail using single-factor experiments. The optimum conditions were determined as follows: T = 880°C; t = 60 min; Na2CO3/paste mass ratio = 2.8:1; and the Zn O dosage is equal to the stoichiometric requirement. Under the optimum conditions, the direct recovery rate of lead reached 98.14%. The results suggested that increases in temperature and salt dosage improved the direct recovery rate of lead. XRD results and thermodynamic calculations indicated that the reaction approaches of lead and sulfur were Pb SO4→Pb and Pb SO4→Zn S, respectively. Sulfur was fixed in the form of Zn S, whereas the molten salt did not react with other components, serving only as a reaction medium.

High-performance lithium-sulfur battery based on porous N-rich g-C_(3)N_(4) nan-otubes via a self-template method

The commercial development of lithium-sulfur batteries(Li-S)is severely limited by the shuttle effect of lithium polysulfides(LPSs)and the non-conductivity of sulfur.Herein,porous g-C_(3)N_(4) nanotubes(PCNNTs)are synthesized via a self-template method and utilized as an efficient sulfur host material.The one-dimensional PCNNTs have a high specific surface area(143.47 m^(2)·g^(-1))and an abundance of macro-/mesopores,which could achieve a high sulfur loading rate of 74.7wt%.A Li-S battery bearing the PCNNTs/S composite as a cathode displays a low capacity decay of 0.021% per cycle over 800 cycles at 0.5 C with an initial capacity of 704.8 mAh·g^(-1).PCNNTs with a tubular structure could alleviate the volume expansion caused by sulfur and lithium sulfide during charge/discharge cycling.High N contents could greatly enhance the adsorption capacity of the carbon nitride for LPSs.These synergistic effects contribute to the excellent cycling stability and rate performance of the PCNNTs/S composite electrode.

Corrosion behavior of hafnium in anhydrous isopropanol and acetonitrile solutions containing bromide ions

The corrosion behaviors of hafnium in Et4NBr isopropanol and acetonitrile(ACN)solutions were investigated usingelectrochemical measurements,ICP-AES and SEM techniques.Results revealed that the open circuit potential gets more positive dueto the increased passivity of the surface oxide film with increasing immersion time until it reaches a steady state value.Thepotentiodynamic anodic polarization curves did not exhibit an active dissolution region near corrosion potential due to the presenceof an oxide film on the electrode surface,which was followed by pitting corrosion.SEM images confirmed the existence of pits onthe electrode surface.Cyclic voltammetry and galvanostatic measurements allowed the pitting potential(φpit)and the repassivationpotential(φp)to be determined.φpit increased with increasing potential scanning rate but decreased with increasing temperature,Br-concentration and ACN concentration.The impedance spectra showed that the resistances of the solution and charge transferdecreased with the increase of ACN concentration.

Optimization of parameters, characterization and thermal property analysis of hafnium ethoxide synthesized by electrochemical method

Hafnium ethoxide was synthesized using electrochemical method.Optimization experiments were used to optimizevarious parameters namely Et4NBr concentration(c):0.01?0.06mol/L,solution temperature(t):30?78°C,polar distance(D):2.0?4.0cm and current density(J):100?400A/m2.The electrolytic products obtained under optimum conditions of c=0.04mol/L,t=78°C,D=2.0cm and J=100A/m2were further isolated by vacuum distillation under5kPa.The product was characterized byFourier transform infrared(FT-IR)spectra,nuclear magnetic resonance(NMR)spectra.The results indicated that the product washafnium ethoxide.ICP analysis suggested that the content of hafnium ethoxide in the final product exceeded99.997%.Thermalproperties of the product were analyzed by TG/DTG.The vaporization enthalpy of hafnium ethoxide was found to be79.1kJ/mol.The result confirmed that hafnium ethoxide was suitable for the preparation of hafnium oxide by atomic layer deposition.

废三元锂离子电池正极材料脱锂渣的淀粉还原浸出动力学

以淀粉为还原剂从废三元锂离子电池(LIBs)正极材料脱锂渣中回收Ni、Co和Mn,并研究其浸出动力学和机理。系统地研究搅拌速率、浸出温度、H_(2)SO_(4)浓度和淀粉用量对Ni、Co和Mn浸出率的影响。结果表明,在搅拌速率为500 r/min、硫酸浓度为1.5 mol/L、淀粉用量为6 g/L、浸出温度为80℃和浸出时间为60 min的优化条件下,Ni、Co和Mn的浸出率分别达到98.07%、96.52%和98.06%。根据冶金过程液固反应动力学模型,脱锂渣的浸出动力学可以用化学反应控制的未反应收缩核模型很好地进行描述。在浸出反应中,Ni、Co和Mn的表观反应活化能分别为93.32、102.84和95.68 k J/mol,H_(2)SO_(4)的表观反应级数分别为0.9225、1.0335和1.1285。淀粉容易制取、成本低,可取代传统还原剂用于从废三元锂电池中提取有价金属。

HYPERBRANCHED AROMATIC POLYMERS OBTAINED VIA SELF-CONDENSATION

Hyperbranched aromatic polymers were prepared by Friedel-Crafts reaction with Lewis acid, AlCl3 and ZnCl2, as the catalysts. In this work, hyperbranched polybenzyl (PB) and poly(methylene)naphthalene (PN) were synthesized and characterized by H-1-NMR and GPC. In addition, their florescence properties were measured with steady-state florescence spectra in THF and ethylene dichloride. The quantum yields of polybenzyl and poly(methylene)naphthalene in ethylene dichloride are much larger than those in THE.

MORPHOLOGICAL CHARACTERIZATION OF POLY (N-VINYLCARBAZOLE) OBTAINED WITH ASYMMETRICALLY STEREOSELECTIVE POLYMERIZATION

The morphological characterizations of poly(N-vinylcarbazole)(PVCZ) obtained by asymmetrically stereoselective polymerization were studied using x-ray diffraction pattern, DSC and GPC. The results show that the PVCZs have lower crystallinities (11.0 similar to 18.6%) and lower melting heats (2.2 similar to 7.5 J/g), but the degree of crystallinities of the PVCZ samples obtained using the organic salts (acid) with chiral or stereodifferentiating ligands are higher than that using radical and general protonic initiator. It has shown that the crystallization is directly related to the packing density of the hexagonal array of the rodlike molecules formed from the helical chain.

Additional gastrectomy in early-stage gastric cancer after non-curative endoscopic resection:a meta-analysis

Background and objective:The role of additional gastrectomy after non-curative endoscopic resection remains uncertain.The present meta-analysis aimed to explore the risk factors for early-stage gastric-cancer patients after non-curative endoscopic resection and evaluate the efficacy of additional gastrectomy.Methods:Relevant studies that reported additional gastrectomy after non-curative endoscopic resection were comprehensively searched in MedLine,Web of Science and EMBASE.We first investigated the risk factors for residual tumor and lymph-node metastasis after non-curative endoscopic resection and then analysed the survival outcome,including 5-year overall survival(OS)and 5-year disease-free survival,of additional gastrectomy.Results:Twenty-one studies comprising 4870 cases were included in the present study.We found that residual tumor was associated with larger tumor size(>3 cm)(odds ratio[OR]=2.81,P<0.001),undifferentiated tumor type(OR=1.78,P=0.011)and positive horizontal margin(OR=9.78,P<0.001).Lymph-node metastasis was associated with larger tumor size(>3 cm)(OR=1.73,P<0.001),elevated tumor type(OR=1.60,P=0.035),deeper tumor invasion(>SM1)(OR=2.68,P<0.001),lymphatic invasion(OR=4.65,P<0.001)and positive vertical margin(OR=2.30,P<0.001).Patients who underwent additional gastrectomy had longer 5-year OS(hazard ratio[HR]=0.34,P<0.001),5-year disease-free survival(HR=0.52,P=0.001)and 5-year disease-specific survival(HR=0.50,P<0.001)than those who did not.Moreover,elderly patients also benefited from additional gastrectomy regarding 5-year OS(HR=0.41,P=0.001).Conclusions:Additional gastrectomy with lymph-node dissectionmight improve the survival of early-stage gastric-cancer patients after non-curative endoscopic resection.However,risk stratification should be performed to avoid excessive treatment.

Mainchain Semifluorinated Polymers with Ultra High Molecular Weight via Reaction-enhanced Reactivity of Intermediate(RERI) Mechanism

Achieving the linear polymers with high molecular weight via step-growth polymerization of A2 and B2 monomers is significantly limited by the requirement of strict stoichiometry of two monomers when the reactivity of A and B groups are not changed during the polymerization.Herein,a unique step-growth polymerization based on copper-catalyzed azide-alkyne cycloaddition(CuAAC)with reactionenhanced reactivity of intermediate(RERI)mechanism was developed for the preparation of mainchain semifluorinated polymers with high molecular weight.The CuAAC polymerization of bis-alkynyl-terminated fluorinated monomers(A2)and 2,2-bis(azidomethyl)propane-1,3-diyl bis(2-methylpropanoate)(BiAz,B2)with RERI effect at different stoichiometric ratio was systematically investigated.The results indicated that the semifluorinated polymers with ultrahigh molecular weight,Mw,MALLS>106 g/mol,could be efficiently synthesized by using excess molar of BiAz monomers.The resultant high-molecular-weight semifluorinated polymers show good thermostability and high hydrophobicity.In addition,the glass transition temperature(Tg)of these mainchain semifluorinated polymers could be tuned conveniently due to the bis-alkynyl-terminated comonomers could be consumed completely when excessive BiAz monomers were used in this this step-growth polymerization.