Müller cells are activated in response to retinal outer nuclear layer degeneration in rats subjected to simulated weightlessness conditions

A microgravity environment has been shown to cause ocular damage and affect visual acuity,but the underlying mechanisms remain unclear.Therefore,we established an animal model of weightlessness via tail suspension to examine the pathological changes and molecular mechanisms of retinal damage under microgravity.After 4 weeks of tail suspension,there were no notable alterations in retinal function and morphology,while after 8 weeks of tail suspension,significant reductions in retinal function were observed,and the outer nuclear layer was thinner,with abundant apoptotic cells.To investigate the mechanism underlying the degenerative changes that occurred in the outer nuclear layer of the retina,proteomics was used to analyze differentially expressed proteins in rat retinas after 8 weeks of tail suspension.The results showed that the expression levels of fibroblast growth factor 2(also known as basic fibroblast growth factor)and glial fibrillary acidic protein,which are closely related to Müller cell activation,were significantly upregulated.In addition,Müller cell regeneration and Müller cell gliosis were observed after 4 and 8 weeks,respectively,of simulated weightlessness.These findings indicate that Müller cells play an important regulatory role in retinal outer nuclear layer degeneration during weightlessness.

Are the two polymorphic sites of anti-Marek’s disease in White Leghorn chickens also suitable for Partridge Shank chickens?

Background:The selection of Marek’s disease(MD)-resistant breeds in Partridge Shank chicken,a popular local chicken breed in Henan Province of China,has practical value.We hypothesized that the two polymorphic sites(rs14527240 located in SMOC1 and GGaluGA156129 located in PTPN3)related to MD resistance in White Leghorn chickens are also applicable to Partridge Shank chickens.Methods:In this experiment,we screened 10 live hens and 2 live roosters with the double GG genotype by genotyping the two sites from 6500 Partridge Shank chickens.Nineteen one-day-old chicks with the double GG genotype were obtained by artificial insemination.Seventy-two one-day-old chickens(19 from the population expansion test and 53 randomly selected from chicken farms)were injected with 2000 plaque-forming units of the Md5 virus strain.After 100 days of infection,all chickens were examined by pathological anatomical examination,histological sectioning,genotyping,and a quantitative polymerase chain reaction of SMOC1 and PTPN3.Results:There was only one site(rs14527240 located in SMOC1)associated with MD in Partridge Shank chickens(p<0.05),but the GG genotype of SMOC1 in Partridge Shank chickens indicated susceptibility to MD.SMOC1 expression in MD-susceptible chickens was also significantly higher than that in MDresistant chickens(p<0.05).Conclusion:Therefore,the MD resistance sites selected from White Leghorn chickens were not completely suitable for Partridge Shank chickens,but they can be used as a reference.This study indicated that SMOC1 plays an important role in screening for MD resistance in poultry.

Novel indirect Z-scheme g-C3N4/Bi2MoO6/Bi hollow microsphere heterojunctions with SPR-promoted visible absorption and highly enhanced photocatalytic performance

The surface plasmonic resonance(SPR)effect of Bi can effectively improve the light absorption abilities and photogenerated charge carrier separation rate.In this study,a novel ternary heterojunction of g-C3N4/Bi2MoO6/Bi(CN/BMO/Bi)hollow microsphere was successfully fabricated through solvothermal and in situ reduction methods.The results revealed that the optimal ternary 0.4 CN/BMO/9 Bi photocatalyst exhibited the highest photocatalytic efficiency toward rhodamine B(RhB)degradation with nine times that of pure BMO.The DRS and valence band of the X-ray photoelectron spectroscopy spectrum demonstrate that the band structure of 0.4 CN/BMO/9 Bi is a z-scheme structure.Quenching experiments also provided solid evidence that the·O^2-(at-0.33 eV)is the main species during dye degradation,and the conduction band of g-C3N4 is only the reaction site,demonstrating that the transfer of photogenerated charge carriers of g-C3N4/Bi2 MoO 6/Bi is through an indirect z-scheme structure.Thus,the enhanced photocatalytic performance was mainly ascribed to the synergetic effect of heterojunction structures between g-C3N4 and Bi2MoO6 and the SPR effect of Bi doping,resulting in better optical absorption ability and a lower combination rate of photogenerated charge carriers.The findings in this work provide insight into the synergism of heterostructures and the SPR absorption ability in wastewater treatment.

Effects of antioxidants on homocysteine thiolactone-induced apoptosis in human umbilical vein endothelial cells

Background and objectives Hyperhomocysteinemia is an independent risk factor for cardiovascular disease.Homocysteine thiolactone(HcyT),one of the homocysteine metabolites in vivo,is toxic both in vivo and in vitro.The aim of this study was to investigate the effect of HcyT on apoptotic damage in human umbilical vein endothelial cells(HUVECs)and the role of antioxidants in the reduction of HcyT-induced apoptosis.Methods HUVECs were cultured in DMEM supplemented with 20%heat inactivated fetal bovine serum cell cultures were maintained in a humidified 5%CO_(2)atmosphere at 37℃.Cytotoxicity was determined by MTT assay,which consists of hypodiploid cells with propidium iodide labeling and intracellular reactive oxygen species levels using 2',7'-dichlorofluorescein diacetate as the probe by flow cytometry.Results HcyT(250-2000μM)induced HUVECs apoptosis in a time-and concentration-dependent manner.Reactive oxygen species levels rose in response to increasing HcyT concentrations at 24-h incubation.The reduction of cell apoptosis by N-acetylcysteine,vitamin E,or pyrrolidine dithiocarbamate,occurred simultaneously with a significant decrease in intracellular reactive oxygen species levels.Conclusion HcyT exerts its cytotoxic effects on endothelial cells through an apoptotic mechanism involving cellular reactive oxygen species production.The capacity of N-acetylcysteine,vitamin E,and pyrrolidine dithiocarbamate to scavenge HcyT-induced cellular reactive oxygen species correlates well with their efficiency to protect against HcyT-promoted apoptotic damage.The protective effect of pyrrolidine dithiocarbamate on cell apoptosis indicates HcyT-generated hydrogen peroxide may provoke cell apoptosis via activating nuclear factor-kappa binding protein.

Study on the Cutting Temperature of the Textured Tool by 3D FEA Simulation

Temperature plays an important role in the life of cutting tools.However,it is sometimes difficult to observe instantaneously because of limited data acquisition,especially for the textured tool.In this paper,the performance of microgroove textured cutting tools for three-dimensional(3D)oblique dry turning of AISI 1045 steel was studied by finite element simulation.The effects of width,depth and spacing of strip micro-texture on cutting temperature and the effect of cutting speed on cutting temperature of strip microtexture tool were studied.The results show that the maximum temperature of the tool and the tip temperature first increase and then decrease with the increase of micro-texture width.When the micro-texture depth increases,the maximum temperature and the tool tip temperature decrease first and then increase.The highest temperature and tip temperature of the tool gradually increase with the increase of micro-texture spacing.The highest temperature and tip temperature of the tool increase with the increase of cutting speed,feed speed and cutting depth.In addition,the effective mechanism of micro-texture parameter for the temperature was proposed.It provides profound guidance for optimizing the microstructure parameters and cutting process of cutting tools according to cutting temperature in this study.It also provides an effective and practical method for the design,innovation and development of microtextured tools.

Polyoxometalate-loaded Nanocellulose Sponge as a Novel Catalyst for the Regioselective Hydroboration of Phenylacetylene

In this work,an amino-modified cellulose nanofiber sponge was prepared and used as a support for polyoxometalate(POM)catalysts with a high loading efficiency.Fourier transform infrared spectroscopy,thermogravimetric analysis,and energy-dispersive X-ray spectroscopy revealed that an Anderson-type POM,(NH4)4[CuMo6O18(OH)6]·5H2O was successfully immobilized on the sponge based on electrostatic interactions.Morphological analysis indicated that the POM-loaded sponge retained its porous structure and that the POM was homogeneously distributed on the sponge walls.The POM-loaded sponge exhibited excellent mechanical properties by recovering 79.9%of its original thickness following a 60%compression strain.The POM-loaded sponge was found to effectively catalyze the hydroboration of phenylacetylenes,yielding excellent conversion and regioselectivity of up to 96%and 99%,respectively.Its catalytic activity remained unchanged after five reuse cycles.These findings represent a scalable strategy for immobilizing POMs on porous supports.

Spectral observation of symmetry-protected selection rules for dynamical high-dimensional parity in alignment magnetic resonance

Multidimensional Floquet-driven alignment systems with dynamical symmetry present various exotic phenomena and applications.However,there are challenges in directly characterizing large-spin dynamical symmetry from spectra.Here,we first observe the symmetry-protected selection rules of dynamical high-dimensional parity in a large-spin(F=4)system.We theoretically construct a Floquet-driven alignment system that can be used to reveal high-dimensional spatiotemporal symmetry.In the experiment,the system is implemented in Cs atomic gas subjected to two-dimensional Floquet-modulated magnetic resonance driving.By developing Floquet detection protocols of alignment double-sided spectra,we directly verify symmetry-protected selection rules of dynamical high-dimensional parity for large-spin systems.This work advances the exploration of dynamical symmetry to large spins,and unravels a universal Floquet scheme for the investigation of symmetry-protected selection rules.

Current sensor based on an atomic magnetometer for DC application

A DC current sensor based on an optically pumped atomic magnetometer is proposed.It has a high linearity in a wide operation range,since the magnetometer measures the absolute magnitude of the magnetic field produced by the current to be measured.The current sensor exhibits a high accuracy with a non-moment solenoid and magnetic shielding to suppress the influence from the environment.The absolute error of the measured current is below 0.08 m A when the range is from 7.5 m A to 750 m A.The relative error is 5.54×10^-5 at 750 m A.