Biochemistry and transcriptome analysis reveal condensed tannins alleviate liver injury induced by regulating cholesterol metabolism pathway

Free cholesterol has been considered to be a critical risk factor of nonalcoholic fatty liver disease(NAFLD).It remains unknown whether dietary intake of condensed tannins(CTs)have distinguishable effects to alleviate liver damage caused by a high cholesterol diet.Male C57BL/6 mice were fed a high cholesterol diet for 6 weeks,and given CTs treatment at a dosage of 200 mg/(kg·day)at the same time.The results indicated that compared with mice fed a normal diet,a high cholesterol diet group resulted in significant weight loss,dysregulation of lipid metabolism in blood and liver,and oxidative stress in the liver,but CTs treatment dramatically reversed these negative effects.Hematoxylin and eosin(H&E)staining and frozen section observation manifested that CTs treatment could effectively reduce the deposition of liver cholesterol and tissue necrosis caused by high cholesterol intake.CTs alleviated liver injury mainly by regulating the expression of related genes in cholesterol metabolism pathway and AMPK phosphorylation.Our results confirmed that CTs have remarkable cholesterol lowering and anti-liver injury effects in vivo.

Inhibitory effect of procyanidin B2 and tannin acid on cholesterol esterase and their synergistic effect with orlistat

This study was aimed to analyze the effect of procyanidin B2(PC)and tannin acid(TA)on the activities of cholesterol esterase(CEase)and the inhibitory mechanisms of enzymatic activity.The interaction mechanisms were investigated by enzymatic kinetics,multi-spectroscopy methods,thermodynamics analysis,molecular docking,and dynamic simulations.PC and TA could bind with CEase and inhibit the activity of enzyme in a mixed-competitive manner and non-competitive manner,which was verified by molecular docking simulations and dynamics simulations.Also,PC and TA showed the synergistic inhibition with orlistat.Fluorescence,UVvis and the thermodynamic analysis revealed that the complexes were formed from CEase and inhibitors by noncovalent interaction.As revealed by the circular dichroism results,both PC and TA decreased enzymatic activities by altering the conformations of CEase.The inhibition of PC and TA on CEase might be one mechanism for its cholesterol-lowering effect.

Allergen degradation of bee pollen by lactic acid bacteria fermentation and its alleviatory effects on allergic reactions in BALB/c mice

Food allergy as a global health problem threatens food industry.Bee pollen(BP)is a typical food with allergenic potentials,although it performs various nutritional/pharmacological functions to humans.In this study,lactic acid bacteria(LAB)were used to ferment Brassica napus BP for alleviating its allergenicity.Four novel allergens(glutaredoxin,oleosin-B2,catalase and lipase)were identified with significant decreases in LAB-fermented BP(FBP)than natural BP by proteomics.Meanwhile,metabolomics analysis showed significant increases of 28 characteristic oligopeptides and amino acids in FBP versus BP,indicating the degradation of LAB on allergens.Moreover,FBP showed alleviatory effects in BALB/c mice,which relieved pathological symptoms and lowered production of allergic mediators.Microbial high-throughput sequencing analysis showed that FBP could regulate gut microbiota and metabolism to strengthen immunity,which were closely correlated with the alleviation of allergic reactivity.These findings could contribute to the development and utilization of hypoallergenic BP products.

The synergistic effect of dietary cholesterol with fruit tannins in forming kidney stones

Prevalence of kidney stones has increased continously over several decades worldwide,the major causes of which are largely unknown.To explore the dietary causes of kidney stones,and reveal mechanisms underlying dietary risk factors inducing kidney stones,animal experiments using mice as the disease model were performed.Eight-week old male CD-1 mice were treated by ethylene glycol,cholesterol or/and apple tannins for 3 d,respectively.In the present study,the crystalline analysis in urine and kidney tissues,HE staining kidney sections as well as observation of micro-stones,tannins and cholesterol deposition in kidneys of mice in different groups were conducted.We found that gavage with ethylene glycol,cholesterol and tannins resulted in mice urine solute supersaturation in renal tubules and forming kidney stones.Significant cholesterol and tannin deposits in mouse kidney were observed by laser confocal microscopy and crystals were shown either adhered with or codeposited with cholesterol and tannin deposits.The primary crystals were found in renal cortex,medullar,especially papilla in the kidney sections under polarized microscope.These findings demonstrate that interaction of cholesterol and tannins in kidney plays a critical role in the formation of kidney stones.

A Disturbance Source Location Method on the Low Frequency Oscillation With Time-varying Steady-state Points

The low frequency oscillation is a serious threat to security and stability of a power grid.How to locate the disturbance source accurately is an important issue to low frequency oscillation disposal.Existing methods have poor adaptability to the low frequency oscillation with time-varying steady-state points because of the limitations in the location criterion derivation.A disturbance source location method on a low frequency oscillation with good generality is presented in the paper.Firstly,the reasons why the steady-state points are time-varying on a low frequency oscillation are analyzed.Then,based on the energy function construction form,the branch transmission energy is decomposed into state energy,reciprocating energy and dissipation energy by mathematical derivation.The flow direction of the dissipation energy shows the source and destination of the disturbance energy,and the specific location of a disturbance source can be identified according to its flow direction.Meanwhile,to meet the needs of energy calculation,a recognition method on the electrical quantities steady-state points is also presented by using the cubic spline interpolation.Simulation results show the correctness of the derivation and analysis on energy structure in the paper,and the disturbance source can be located accurately according to the dissipation energy.

基于原子层沉积的氧化铝和氧化镁纳米薄膜二次电子发射特性

氧化铝、氧化镁具有高二次电子产额(secondary electron yield,SEY)特性,能够作为电子倍增器中打拿极的镀层材料以大幅提升器件的电子倍增效率.本文使用原子层沉积工艺在低阻硅表面分别制备了7组氧化铝、氧化镁纳米薄膜(1~50 nm),并在20 nm氧化镁薄膜表面制备了5组氧化铝纳米薄膜(1~20 nm);表征了薄膜的成分、形貌、厚度和SEY特性,分析了薄膜厚度对样品SEY的影响规律.结果表明,对于硅基底氧化铝和氧化镁纳米薄膜,其SEY随薄膜厚度增加而逐渐增大,但增量逐渐降低;当膜厚超过30 nm时,SEY增量趋于0,说明此时入射电子的侵入深度已经小于膜厚.双层结构SEY半物理理论计算结果表明,纳米薄膜厚度对SEY有显著影响,入射电子能量越低、薄膜越厚,SEY受膜厚影响越明显;随入射电子能量增大,薄膜厚度对SEY的影响逐渐变小,这是由于电子的侵入深度也变大.本研究通过实验结合理论深入分析了纳米级超薄氧化铝和氧化镁薄膜的SEY特性,对于开展电子倍增器中高SEY纳米介质薄膜应用研究具有重要意义.

Visible transparent,infrared stealthy polymeric films with nanocoating of ITO@MXene enable efficient passive radiative heating and solar/electric thermal conversion

Visible transparent yet low infrared-emissivity(ε)polymeric materials are highly anticipated in many applications,whereas the fabrication of which remains a formidable challenge.Herein,visible transparent,flexible,and low-εpolymeric films were fabricated by nanocoating decoration of indium tin oxide(ITO)and MXene on polyethylene terephthalate(PET)film surface through magnetron sputtering and spray coating,respectively.The obtained PET-ITO@MXene(PET-IM)film exhibits lowεof 24.7%and high visible transmittance exceeding 50%,endowing it with excellent visible transparent infrared stealthy by reducing human skin radiation temperature from 32 to 20.8°C,and remarkable zero-energy passive radiative heating capability(5.7°C).Meanwhile,the transparent low-εPET-IM film has high solar absorptivity and electrical conductivity,enabling superior solar/electric to thermal conversion performance.Notably,the three heating modes of passive radiative and active solar/electric can be integrated together to cope with complex heating scenarios.These visible transparent low-εpolymeric films are highly promising in infrared stealth,building daylighting and thermal management,and personal precision heating.

Highly Stereocontrolled Total Syntheses of Cedrane Sesquiterpenes via Cascade [5+2] Cycloaddition/Etherification

Cedrane sesquiterpenes possess common tricyclo[5.3.1.0^(1,5)]undecane core structure.The varied oxa-five-membered ring decorating their core structure to form 8-oxa-tetracyclo[7.2.2.0^(1,5).0^(6,13)]tridecane framework,containing six consecutive chiral centers(including two all-carbon quaternary centers and one oxygenated quaternary carbon center),has proven to be a synthetic challenge and a biosynthetic mystery to date.

Function-oriented optimization design method for underactuated tendon-driven humanoid prosthetic hand

The loss of hand functions in upper limb amputees severely restricts their mobility in daily life.Wearing a humanoid prosthetic hand would be an effective way of restoring lost hand functions.In a prosthetic hand design,replicating the natural and dexterous grasping functions with a few actuators remains a big challenge.In this study,a function-oriented optimization design(FOD)method is proposed for the design of a tendon-driven humanoid prosthetic hand.An optimization function of different functional conditions of full-phalanx contact,total contact force,and force isotropy was constructed based on the kinetostatic model of a prosthetic finger for the evaluation of grasping performance.Using a genetic algorithm,the optimal geometric parameters of the prosthetic finger could be determined for specific functional requirements.Optimal results reveal that the structure of the prosthetic finger is significantly different when designed for different functional requirements and grasping target sizes.A prosthetic finger was fabricated and tested with grasping experiments.The mean absolute percentage error between the theoretical value and the experimental result is less than 10%,demonstrating that the kinetostatic model of the prosthetic finger is effective and makes the FOD method possible.This study suggests that the FOD method enables the systematic evaluation of grasping performance for prosthetic hands in the design stage,which could improve the design efficiency and help prosthetic hands meet the design requirements.