Role of hydrogen sulfide in portal hypertension and esophagogastric junction vascular disease

AIM:To investigate the association between endogenous hydrogen sulfide(H2S)and portal hypertension as well as its effect on vascular smooth muscle cells.METHODS:Portal hypertension patients were categorized by Child-Pugh score based on bilirubin and albumin levels,prothrombin time,ascites and hepatic encephalopathy.Plasma H2S concentrations and portal vein diameters(PVDs)were compared between portal hypertension patients and control participants,as well as between portal hypertension patients with varying degrees of severity.In addition,we established a rabbit hepatic schistosomiasis portal hypertension(SPH)model and analyzed liver morphology,fibrosis grade,plasma and liver tissue H2S concentrations,as well as cystathionineγ-lyase(CSE)activity and phosphorylated extracellular signal-regulated kinase(pERK)1/2,B cell lymphoma(Bcl)-2 and Bcl-XL expression in portal vein smooth muscle cells,in addition to their H2S-induced apoptosis rates.RESULTS:In portal hypertension patients,endogenous H2S levels were significantly lower than those in healthy controls.The more severe the disease was,the lower were the H2S plasma levels,which were inversely correlated with PVD and Child-Pugh score.Liver tissue H2S concentrations and CSE expression were significantly lower in the SPH rabbit livers compared with the control animals,starting at 3 wk,whereas pERK 1/2expressions gradually increased 12-20 wk after SPH model establishment.In portal vein smooth muscle cells,increasing H2S levels led to increased apoptosis,while Bcl-2 and Bcl-XL expression decreased.CONCLUSION:H2S prevents vascular restructuring caused by excessive proliferation of smooth muscle cells via apoptosis induction,which helps to maintain normal vascular structures.

Effects of the vegetative propagation method on juvenility in Robinia pseudoacacia L.

Vegetative propagation is an important method of reproduction and rejuvenation in forestry.The growth and development of asexually propagated trees are influenced by the age and position of the propagule on the plant,effects referred to as cyclophysis and topophysis,respectively.Due to the long lifespans and large body sizes of woody trees,the selection of propagules is critically important.Here,we used three vegetative propagation methods(shoot cutting,root sprouting,and root cutting)to study the effect of different regeneration methods on juvenility of the resulting black locust plants,with seed-derived seedlings used as a control.Most characteristics of plantlets generated by rootsprouting were similar to those of seed-derived seedlings,including leaf traits and leaf anatomical structure.However,there were significant differences between the plantlets derived from shoot-cuttings and seedlings from seeds.Furthermore,the data showed that some of these agerelated small RNAs and genes differed in expression among propagation methods and between plantlets/seedlings and mature trees.These agerelated small RNAs,genes,and transcription factors may be used as molecular markers of juvenility and phase transitions in black locust.Our results provide useful information for the optimal propagation of woody trees and for further research into the mechanisms of root regeneration.

Permanent lining castable with low bulk density and thermal conductivity:bauxite castable for tundish obtained by adding pearlescent sand

The low thermal conductivity and light mass of castables for tundish permanent linings are crucial for minimizing the heat loss of molten steel.In consideration of the low bulk density and thermal conductivity of pearlescent sand,the thermal insulation performance of castables was attempted to be improved by adding pearlescent sand.Pearlescent sand was modified to prevent the strength of its porous structure from deteriorating.The modification mechanism of pearlescent sand and the effect of pearlescent sand on the performance of bauxite castables were studied.The results suggested that the addition of the modified pearlescent sand significantly raised the apparent porosity and decreased the bulk density of bauxite castable.At 1000℃,the bulk density of more than 60%of the modified pearlescent sand-bauxite castable was only 2.03 g/cm^(3).The mechanical properties and thermal shock resistance of the modified pearlescent sand-bauxite castable were inferior to those of conventional bauxite castable but were adequate to meet the use conditions of casta-bles for tundish permanent linings.At high temperatures of 200-800℃,the thermal conductivity of more than 60%of the modified pearlescent sand-bauxite castable was smaller than that of conventional bauxite castable.The addition of the modified pearlescent sand can greatly reduce the thermal conductivity and bulk density of bauxite castable.

泡沫分离设备的研究进展

作为一种新型分离技术,泡沫分离技术具有设备简单、能耗低、易于操作、低浓度条件下效率高和无污染等优点,该技术在降低表面活性物质分离成本方面具有极大的潜力,在工业上得到了广泛的应用。本工作分析了近年来文献报道中应用于分离回收蛋白质、有机污染物、天然产物、金属离子、微藻等的各种泡沫分离设备,并结合泡沫分离技术的发展历程将其分为传统泡沫分离设备和改进泡沫分离设备。重点阐述了改进泡沫分离设备的作用机理和分离效果,突显泡沫分离技术的重要性。改进型泡沫分离设备在一定程度上提高了分离效果,但依然存在一些问题,如很多设备在提高富集比的同时也降低了回收率。

针刺和电针治疗功能性消化不良疗效的系统评价和meta分析

Objective:To review systematically the therapeutic effect and safety of acupuncture or electroacupuncture(EA)on functional dyspepsia(FD).Methods:Using computer,the randomized controlled trials(RCTs)of FD treated with acupuncture or EA were retrieved from the databases,i.e.Cochrane Library,PubMed,EMbase and Web of science,from the date of database establishment to June 1,2020.Using the assessment tool of risk of bias in Cochrane Handbook for systematic reviews of interventions,5.1.0,the quality of the included RCTs were evaluated in methodology.Meta-analysis was performed by RevMan 5.3 software.Results:A total of 10 articles were included,with 1202 cases involved.In this study,the effectiveness of EA or acupuncture on FD was analyzed in comparison with the treatment with sham-acupuncture,sham-EA or western medication.The results indicated that compared with sham-acupuncture or shamEA,acupuncture or EA greatly relieved the clinical symptoms of FD(SMD=-3.03,95%Cl[-3.56,-2.50],P<0.00001)and obtained a higher clinical response rate(OR=5.09,95%CI[3.30,7.86],P<0.00001),but the difference was not significant statistically in gastric electrical activity(P>0.05).Compared with gastric prokinetics,acupuncture or EA more effectively reduced the symptom score(MD=-3.03,95%CI[-3.56,-2.50],P=0.02),but the differences were not significant in the aspects of the improvement of clinical effective rate(OR=1.33,95%CI[0.70,2.52],P=0.39),the promotion of gastric half-emptying(MD=0.23,95%Cl[-1.94,2.40],12=0%,P=0.83),the promotion of motilin secretion(SMD=-0.06,95%CI[-0.23,0.11],I^(2)=0%,P=0.50)and the increase of gastric electrical activity(MD=-0.01,95%Cl[-0.03,0.01],I^(2)=0%,P=0.41).The three RCT studies with adverse events reported indicated that the difference in the incidence of the adverse events was not significant statistically in comparison of acupuncture with sham-acupuncture or gastric prokinetic agent(P<0.05).Conclusion:Regarding the improvement in the symptoms of FD,the effect of EA or acupuncture is superior to the sham-acupuncture group or the western medication group.Simultaneously,the clinical response rate in the treatment with EA or acupuncture is higher than the sham-acupuncture group.During the treatment with EA,some adverse reactions happened in treatment of FD with acupuncture or western medication.Even though there are the limitations in quality and quantity of the included trials,EA and acupuncture still deserve to be promoted in treatment of FD.However,more studies of RCTs with largescale sample,high quality and multiple centers are required for a further verification of the therapeutic effect.

Improved plasmon-assisted photoelectric conversion efficiency across entire ultraviolet-visible region based on antenna-on zinc oxide/silver three-dimensional nanostructured films

ZnO has received tremendous attention for applications in photoelectrochemical water splitting, photocatalysis, and photovoltaic devices. However, the photoelectric conversion efficiency of ZnO is limited by the rapid recombination of photoexcited electron-hole pairs and the wide band gap, which allows only a small fraction of the solar spectrum to be absorbed. Recently, substantial research efforts have aimed to increase the photoelectric conversion efficiency across the entire ultraviolet-visible （UV-vis） spectrum by coupling semiconductors such as ZnO with noble metal nanoparticles （NPs）. In this stud~ we compare the performance of a pure ZnO film and ZnO/Ag nanostructured films as photoelectrodes. We show that under broad-spectrum UV-vis illumination, the photocurrent generated in the ZnO/Ag three-dimensional （3D） nanostructured films increases 3.75 times relative to the photocurrent generated in the pure ZnO films. We attribute the high photocurrent to the electric-field enhancement associated with the localized surface plasmon resonance of the Ag NPs, which are present at a high density in the 3D nanostructured films, and to the creation of photoexcited hot electrons in Ag that are transferred to ZnO, promoting electron-hole pair separation. We propose a mechanism to explain the observed enhancement of the photoelectric conversion efficiency.

N-carbamoylglutamate improves lipid metabolism, inflammation, and apoptosis responses in visceral adipocytes of Japanese seabass (Lateolabrax japonicus), in vivo and in vitro

This study applied in vivo and in vitro methods to investigate the effect of dietary N-carbamoylglutamate(NCG)on lipid metabolism,inflammation and apoptosis related-gene expression in visceral adipose tissue and isolated adipocytes of Japanese seabass(Lateolabrax japonicus).A basal diet and a test diet supplemented with 720 mg/kg NCG were fed to the fish for 10 weeks.During the growth trial,no mortality and no significant differences in growth performance were observed in fish between the 2 groups(P>0.05).Plasma Arg content and mRNA level of argininosuccinate synthetase(ASS)in adipose tissue were significantly increased,which indicated that NCG inclusion promoted endogenous Arg synthesis.Thereafter,the potential effects of NCG treatment on lipid metabolism-related genes expression were studied through in vivo and in vitro methods.In the present study,we successfully established a primary adipocytes culture system and isolated pre-adipocytes in vitro of Japanese seabass for the first time.Both the results in vivo and in vitro showed that NCG treatment decreased the mRNA levels of genes related to adipogenesis(fatty acid synthase,FASN),cholesterol synthesis(3-hydroxy-3-methylglutaryl-CoA reductase,HMGCR)and fat deposition(lipoprotein lipase[LPL]and leptin),which revealed the underlying mechanism of NCG on reducing fat deposition.The results of this study demonstrated that NCG inclusion reduced the expression of inflammatory and apoptosis cytokines markedly in vivo and in vitro.In conclusion,NCG did exert beneficial effects on ameliorating adipo-genesis,inflammation and apoptosis via promoting Arg endogenous synthesis in Japanese seabass.