Effects of different energy levels in low-protein diet on liver lipid metabolism in the late-phase laying hens through the gut-liver axis

Background The energy/protein imbalance in a low-protein diet induces lipid metabolism disorders in late-phase laying hens.Reducing energy levels in the low-protein diet to adjust the energy-to-protein ratio may improve fat deposition,but this also decreases the laying performance of hens.This study investigated the mechanism by which different energy levels in the low-protein diet influences liver lipid metabolism in late-phase laying hens through the enterohepatic axis to guide feed optimization and nutrition strategies.A total of 288 laying hens were randomly allocated to the normal-energy and normal-protein diet group(positive control:CK)or 1 of 3 groups:lowenergy and low-protein diet(LL),normal-energy and low-protein diet(NL),and high-energy and low-protein diet(HL)groups.The energy-to-protein ratios of the CK,LL,NL,and HL diets were 0.67,0.74,0.77,and 0.80,respectively.Results Compared with the CK group,egg quality deteriorated with increasing energy intake in late-phase laying hens fed low-protein diet.Hens fed LL,NL,and HL diets had significantly higher triglyceride,total cholesterol,acetylCo A carboxylase,and fatty acid synthase levels,but significantly lower hepatic lipase levels compared with the CK group.Liver transcriptome sequencing revealed that genes involved in fatty acid beta-oxidation(ACOX1,HADHA,EHHADH,and ACAA1)were downregulated,whereas genes related to fatty acid synthesis(SCD,FASN,and ACACA)were upregulated in LL group compared with the CK group.Comparison of the cecal microbiome showed that in hens fed an LL diet,Lactobacillus and Desulfovibrio were enriched,whereas riboflavin metabolism was suppressed.Cecal metabolites that were most significantly affected by the LL diet included several vitamins,such as riboflavin(vitamin B2),pantethine(vitamin B5 derivative),pyridoxine(vitamin B6),and 4-pyridoxic acid.Conclusion A lipid metabolism disorder due to deficiencies of vitamin B2 and pantethine originating from the metabolism of the cecal microbiome may be the underlying reason for fat accumulation in the liver of late-phase laying hens fed an LL diet.Based on the present study,we propose that targeting vitamin B2 and pantethine(vitamin B5 derivative)might be an effective strategy for improving lipid metabolism in late-phase laying hens fed a low-protein diet.

打造教师教学发展共同体,多校共上一堂课——“大学化学实验课程群虚拟教研室”教研活动初探及成效

介绍“大学化学实验课程群虚拟教研室”在创新教研形态、加强教学研究、共建优质资源以及开展教师培训等方面开展的一系列工作及取得的初步实效。重点阐明了“多校共上一堂课,共享教学云资源”的示范教学直播课活动的教研形式以及教学内容的选取原则。

环境污染物布洛芬吸附材料的研究进展

目前,由于布洛芬引起的环境污染问题日益严重,危害人们的身体健康,如何解决工业生产和日常生活所产生的布洛芬污染成为一个迫切需要解决的科学问题。因此,国内外学者在开发新型吸附材料方面开展了一系列研究。文章概述了布洛芬的性质及污染现状等,重点总结了目前几类重要的布洛芬吸附材料。生物质炭材料具有环保、成本低、吸附能力较强、不产生二次污染等特点,使用广泛,应用价值和发展前景较好。分子印迹材料具有良好的生物相容性,也具有其他材料无法比拟的特异性分子识别能力,是一种新型的吸附功能材料,发展空间很大。介孔材料具有极高的比表面积、规则有序的孔道结构、狭窄的孔径分布等特点,是一种较好的吸附布洛芬的功能材料。另外,国内外学者利用天然聚合物、复合纳米材料、表面活性剂等其他材料,通过优化和改性设计合成了多种吸附性能优异的高分子材料。

Magnetic resonance imaging of knees:a novel approach to predict recombinant human growth hormone therapy response in short-stature children in late puberty

Background There is no appropriate tool to predict recombinant human growth hormone(rhGH)response before therapy initiation in short-stature children in late puberty.The current study aimed to explore the associations between magnetic resonance imaging(MRI)stages of the knee growth plates and rhGH response in short-stature children in late puberty.Methods In this prospective cohort study,short-stature children in late puberty were treated with rhGH and followed up for 6 months.We proposed a novel knee MRI staging system according to the growth plate states of distal femurs or proximal tibias and divided the participants into three groups:unclosed growth plate group,marginally closed growth plate group,and nearly closed growth plate group.The primary outcomes were height gain and growth velocity(GV),which were assessed three months later.Results Fifty participants were enrolled,including 23 boys and 27 girls.GV and height gain after 6 months of rhGH therapy decreased successively in the three groups with an increased degree of growth plate fusion,especially when grouped by proximal tibias(GV_(1-3 mon)from 9.38 to 6.08 to 4.56 cm/year,GV_(4-6 mon)from 6.75 to 4.92 to 3.25 cm/year,and height gain from 4.03 to 2.75 to 1.95 cm,all P<0.001).Moreover,the MRI stages of growth plates independently served as a significant variable for GV and height gain after therapy,especially when grouped by proximal tibias(all P<0.01).Conclusion The MRI staging method is expected to be an effective tool for predicting rhGH response before therapy initiation in short-stature children in late puberty.

Microstructure and mechanical properties of CoCrNi-Mo medium entropy alloys:Experiments and first-principle calculations

The effect of Mo additions on the microstructures and mechanical properties of CoCrNi alloys was investigated,meanwhile,ab initio calculations are performed to quantitatively evaluate the lattice distortion and stacking fault energy(SFE).The yield strength,ultimate tensile strength,and elongation of(CoCrNi)_(97)Mo_(3)alloy are 475 MPa,983 MPa and 69%,respectively.The yield strength is increased by~30%and high ductility is maintained,in comparison with CoCrNi alloy.Besides the nano-twins and dislocations,the higher density of stacking faults is induced during the tensile deformation for(CoCrNi)_(97)Mo_(3)alloy.Ab initio calculation results indicate the mean square atomic displacement(MSAD)and SFE value of(CoCrNi)_(97)Mo_(3)alloy is 42.6 pm^(2)and-40.4 mJ/m^(2)at 0 K,respectively.The relationship between mechanical properties and MSAD,SFE for various multiple principal element alloys is discussed.