Plasmodium yoelii infection inhibits murine leukaemia WEHI-3 cell proliferation in vivo by promoting immune responses

Background:Leukaemia is a malignant leukocyte disorder with a high fatality rate,and current treatments for this disease are unsatisfactory.Therefore,new therapeutic strategies for leukaemia must be developed.Malaria parasite infection has been shown to be effective at combating certain neoplasms in animal experiments.This study is to demonstrate the anti-leukaemia activity of malaria parasite Plasmodium yoelii(P.yoelii)infection,.Methods:In this study,the proportion of CD3,CD19,CD11b and Mac-3 cells was analysed by flow cytometry;the levels of IFN-γand TNF-αin individual serum samples were measured by enzyme-linked immunosorbent assay,and the phagocytic activity of macrophages and natural killer(NK)cell activity were measured by flow cytometry.Results:We found that P.yoelii infection significantly attenuated the growth of WEHI-3 cells in mice.In addition,tumor cell infiltration into the murine liver and spleen was markedly reduced.We also demonstrated that malaria parasite infection elicited anti-leukaemia activity by promoting immune responses,including increasing the surface markers of T cells(CD3)and B cells(CD19);decreasing the surface markers of monocytes(CD11b)and macrophages(Mac-3);inducing the secretion of IFN-γand TNF-α;and increasing NK cell and macrophage activity.Conclusions:Malaria parasite infection significantly decreases the number of myeloblasts and inhibits neoplasm proliferation in mice.In addition,malaria parasite infection inhibits murine leukaemia by promoting immune responses.

Meso-scale corrosion expansion cracking of ribbed reinforced concrete based on a 3D random aggregate model

In reinforced concrete structures,corrosion of the rebar produces 2–6 times more corrosion product than the original material,creating pressure on the surrounding concrete,leading to cracking.The study of corrosion and cracking in reinforced concrete structures is therefore of great importance for enhancing the durability of concrete.Unlike many previous studies,we used ribbed rebar similar to that used commercially and considered the mechanical behavior of the interface transition zone(ITZ)between the aggregate and mortar to simulate the processes of corrosion and cracking of reinforced concrete structures.We explored the failure mode of the interface layer under uniform corrosion and the influence of different factors on the corrosion expansion cracking and the shedding mode of a concrete cover.This was achieved by establishing a three-phase meso-scale model of concrete based on secondary development of ABAQUS,simulating the mechanical behavior of the ITZ using a cohesive element,and establishing a rust expansion cracking model for single and multiple rebars.The results showed that:(1)Under uniform rust expansion,concrete cracks are distributed in a cross pattern with a slightly shorter lower limb.(2)When the corrosion rate is low,the ITZ is not damaged.With an increase in the corrosion rate,the proportion of elements with tensile damage in the ITZ first increases and then decreases.(3)In the case of a single rebar,the larger the cover thickness,the higher the corrosion rate corresponding to ITZ failure,and the arrangement of the rebar has little influence on the ITZ failure mode.(4)In the case of multiple rebars,the concrete cover cracks when the rebar spacing is small,and wedge-shaped spalling occurs when the spacing is large.

Reaction pathway change on plasmonic Au nanoparticles studied by surface-enhanced Raman spectroscopy

Gold nanoparticles(Au NPs)are nanoscale sources of light and electrons,which are highly relevant for their extensive applications in the field of photocatalysis.Although a number of research works have been carried out on chemical reactions accelerated by the energetic hot electrons/holes,the possibility of reaction pathway change on the plasmonic Au surfaces has not been reported so far.In this proof-ofconcept study,we find that Au NPs change the reaction pathway in photooxidation of alkyne under visible light irradiation.This reaction produces benzil(—CO—CO—)without the presence of Au NPs.In contrast,as indicated by surface-enhanced Raman spectroscopic(SERS)results,the C—C triple bonds(—C≡C—)adsorbed on Au NPs are converted into carboxyl(—COOH)and acyl chloride(—COCl)groups.The plasmonic Au NPs not only provide energetic charge carriers but also activate the reactant molecules as conventional heterogeneous catalysts.This study discloses the second role of plasmonic NPs in photocatalysis and bridges the gap between plasmon-driven and conventional heterogeneous catalysis.