Simulation of charge-exchange induced NBI losses on EAST

The neutral beam injection is widely adopted in tokamaks as a key heating tool,playing a crucial role in generating burning plasmas.However,the loss of beam ions can damage the first wall and reduce the heating efficiency,resulting in failure to maintain steady-state conditions.In this work,the effect of neutral particles in the edge on fast ions generated by NBI in the Experimental Advanced Superconducting Tokamak(EAST)device is studied using the particle tracer code(PTC).The poloidal distribution of neutral particles is calculated by edge plasma simulation code SOLPS-ITER.In this simulation,four beam lines in EAST are considered:co-current tangential(co-tang),co-current perpendicular(co-perp),counter-current tangential(ctr-tang)and counter-current perpendicular(ctr-perp).It is shown that,in the absence of neutral particles,the loss fraction of ctr-injection is considerably higher than that of the co-injection.When considering the neutral particles,it is found that the ctr-perp injection demonstrates a significant variation in particles loss fraction(ranging from 18.56%to 25.42%)compared to the other three injection configurations.In terms of the loss fraction induced by neutral particles,ctr-injection exceeds co-injection,and perpendicular configuration exceeds tangential configuration.Furthermore,the difference of charge exchange ratios of three different energy(full energy,half energy,one third energy)of the four injections can be attributed to variations in the poloidal trajectories associated with each of these injections.Moreover,approximately half of fast ions which undergo neutralization directly lose to the first wall while the rest re-enter the bulk plasma and re-ionize.Except for the ctr-tang injection,the reionization ions from the other three injections exhibit effective confinement.

Repeated pregnancy losses with multiple aneuploidies and major genomic imbalance:A case report

Rationale:If one of the partners is having balanced autosomal translocation,it is usually observed that the offspring inherit either normal chromosomes,balanced translocation identical to one of the parent or unbalanced chromosomal rearrangements of the same parental chromosome having translocation.Concern:A unique case presented with history of 8 miscarriages for genetic counseling.The last abortus material evaluation showed monosomy of chromosome X(Turner syndrome)in all the analyzed cells.There was a history of infertility and also repeated second trimester abortions on the paternal side.On the maternal side,there was a history of intellectual disability.Diagnose:History of repeated abnormal pregnancy outcomes.Wife’s karyotype is normal;however,husband shows translocation between chromosome 4 and 22.Intervention:Peripheral blood sample around 3 mL was collected for karyotype.Embryo biopsy was done and DNA was extracted and processed for whole exome sequencing.Outcomes:Wife’s karyotype is normal and husband has translocation between chromosome 4 and 22.Surprisingly,the entire pregnancy outcome including embryo screening has different,complete or partial aneuploidies of chromosomes other than chromosome 4 and 22.Main lesson:Though the translocation in one of the parent is balanced,we have to think beyond traditional ways for evaluating a couple with repeated pregnancy loss as we cannot predict the errors at cell division.Option of in vitro fertilization and preimplantation genetic diagnosis in couples having balanced translocations should be discussed so that early intervention can prevent the agony of pregnancy loss.

Increasing realism in modelling energy losses in railway vehicles and their impact to energy-efficient train control

The reduction of energy consumption is an increasingly important topic of the railway system.Energy-efficient train control(EETC)is one solution,which refers to mathematically computing when to accelerate,which cruising speed to hold,how long one should coast over a suitable space,and when to brake.Most approaches in literature and industry greatly simplify a lot of nonlinear effects,such that they ignore mostly the losses due to energy conversion in traction components and auxiliaries.To fill this research gap,a series of increasingly detailed nonlinear losses is described and modelled.We categorize an increasing detail in this representation as four levels.We study the impact of those levels of detail on the energy optimal speed trajectory.To do this,a standard approach based on dynamic programming is used,given constraints on total travel time.This evaluation of multiple test cases highlights the influence of the dynamic losses and the power consumption of auxiliary components on railway trajectories,also compared to multiple benchmarks.The results show how the losses can make up 50%of the total energy consumption for an exemplary trip.Ignoring them would though result in consistent but limited errors in the optimal trajectory.Overall,more complex trajectories can result in less energy consumption when including the complexity of nonlinear losses than when a simpler model is considered.Those effects are stronger when the trajectory includes many acceleration and braking phases.

Unraveling the efficiency losses and improving methods in quantum dot-based infrared up-conversion photodetectors

Quantum dot-based up-conversion photodetector,in which an infrared photodiode(PD)and a quantum dot light-emitting diode(QLED)are back-to-back connected,is a promising candidate for low-cost infrared imaging.However,the huge efficiency losses caused by integrating the PD and QLED together hasn’t been studied sufficiently.This work revealed at least three origins for the efficiency losses.First,the PD unit and QLED unit usually didn’t work under optimal conditions at the same time.Second,the potential barriers and traps at the interconnection between PD and QLED units induced unfavorable carrier recombination.Third,much emitted visible light was lost due to the strong visible absorption in the PD unit.Based on the understandings on the loss mechanisms,the infrared up-conversion photodetectors were optimized and achieved a breakthrough photon-to-photon conversion efficiency of 6.9%.This study provided valuable guidance on how to optimize the way of integration for up-conversion photodetectors.

Optimal Sizing and Power Losses Reduction of Photovoltaic Systems Using PVsyst Software

This paper presents a method for optimizing a grid-connected photovoltaic system through an LCL filter. An algorithm based on particle swarm optimization (PSO) is used to determine the number of batteries, the number of panels in series and in parallel, as well as to evaluate the joule losses due to cable heating and the switching losses of the multilevel inverters. This system is applied to a village named YAGOUA, located in the far north of Cameroon. The evaluation of the Joule effect and the switching losses as well as the regulation of the voltage level at the point of common coupling (PCC) are carried out in PVsyst and Matlab software, then at IEEE 33 bus. This algorithm reduced the Joule losses to 1.2% and the switching losses to 2.2%. A power of 210.4 MWh is produced, to be injected in the electrical network via an LCL filter. The THD calculation gave a rate of 3.015% in accordance with the 519 standards. Synchronization through the Phase Locked Loop (PLL) is performed. After the power was injected into the grid, the voltage and current remained in phase, showing the power factor correction and the efficiency of the filter. According to NASA meteorological data, the locality of YAGOUA gives the global solar irradiation forecast of 6.8 kW/m2.

Assessment of Intangible Losses in Earthquake Engineering

In order to find optimum design parameters in earthquake engineering, an objective function is optimized. This function comprises the initial cost of a structure and the cost due to the damage of earthquakes. Intangible losses may be included in the latter, such as how much society is willing to invest to preserve a human life. In this paper, the expression of the objective function is developed in terms of the seismic design coefficient, and the aforementioned intangible loss is calculated from both the individual point of view and that of society. The calculation of the intangible is based on utility curves. Finally, optimum seismic design coefficients are calculated for a firm ground site.

CBCT测量解剖参数在上颌第一磨牙缺失患者种植术前的临床应用价值

目的探究应用锥形束CT(CBCT)测量解剖参数在上颌第一磨牙缺失患者种植术前的临床应用价值。方法选取2022年5月至2024年5月中日友好医院收治的上颌第一磨牙缺失且拍摄CBCT的89例患者,比较不同性别、年龄、缺失侧、缺失时间上颌第一磨牙缺失患者残余牙槽嵴的高度和宽度的差异,并观察患者上颌窦外侧壁血管分型。结果不同年龄、缺失侧、缺失时间上颌第一磨牙缺失患者残余牙槽嵴的高度和宽度比较差异无统计学意义(P>0.05);不同性别上颌第一磨牙缺失患者残余牙槽嵴的高度比较差异无统计学意义(P>0.05),上颌第一磨牙缺失男性患者残余牙槽嵴的宽度大于女性患者[(9.0±2.7)mm比(7.5±2.0)mm](P<0.01);在89例上颌第一磨牙缺失患者的178侧上颌窦中,69.10%(123/178)的上颌窦外侧壁存在血管,其中骨内型占比最高,为70.73%(87/123)。结论CBCT可用于测量残余牙槽嵴的高度和宽度以及评估上颌窦外侧壁血管分型,可为种植术提供相关的术前指导。

Characteristics of Nitrogen and Phosphorus Losses in Different Crop Rotation Systems in the North of Erhai Lake Basin

[Objective] Nitrogen and phosphorus losses of surface runoff in various crop rotation systems in the north of Erhai Lake basin were studied with the objective to provide references for risk evaluation of environmental pollution and formulating countermeasures to control the nonpoint source pollution from agriculture.[Method] Water samples collected in four typical crop rotation systems distributed in seven towns（townships） in the north of Erhai Lake basin were investigated,as well as the fertilizer input,to explore the dynamic change of nitrogen and phosphorus content in surface water of farmland and ditch water,and the correlation between fertilizer input and the concentrations of nitrogen and phosphorus in the surface water of farmland and in the ditch water.[Result] The results showed that nitrogen loss in surface water of farmland in different crop rotation systems differed greatly,and the risk of nitrogen loss was 38% lower in broad bean-rice crop rotation than that in garlic-rice crop rotation.The water soluble nitrogen was the primary form of nitrogen loss.The content of water soluble nitrogen was significantly higher in garlic-rice crop rotation than that in the other rotation systems,and the concentrations of nitrogen in the surface water of farmland in different crop rotation systems followed the sequence below：garlic-rice crop rotationryegrass-rice crop rotationbroad bean-rice crop rotationrape-rice crop rotation.The loss of phosphorus in the surface water of farmland was relatively low and phosphorus combined with silt was the primary form for phosphorus loss.There was no significant difference of the loss of various forms of phosphorus in different crop rotation systems.The contents of total nitrogen and total phosphorus in the surface water of farmland were higher than that in ditch water,with increasing rates of total nitrogen and total phosphorus in ditch water of 72% and 82%,respectively.Topdressing was the critical reason for the high concentrations of nitrogen and phosphorus in the surface water,which also caused the increasing load to the ditch water.[Conclusion] Both the nitrogen and phosphorus loss were the highest in garlic-rice crop rotation.Reasonable crop rotation systems should be established based on both the environmental and economic benefits.This study provided references for controlling the nonpoint source pollution of farmland and improving the water quality of Erhai Lake.

基于特征增强和样本充分学习的红外飞机检测

针对深度学习单阶段检测算法对红外飞机目标的特征提取能力不足以及样本学习不充分的问题,提出基于特征增强的全局上下文机制(FEGCM)和样本充分学习的目标检测算法。FEGCM可获取包含目标的全局信息与局部信息的特征图,从而提高特征提取网络对目标特征的提取能力。通过在Focal Loss中添加调制因子,在关注难负样本学习的基础上,充分利用包含目标特性的部分易负样本,使得样本充分学习,从而帮助检测算法学习到更有意义的目标特征。实验表明,所提算法在自制红外飞机数据集上的mAP_(50)达到96.9%,能够有效实现红外飞机目标检测。

Inhibition of the NLRP3 inflammasome attenuates spiral ganglion neuron degeneration in aminoglycoside-induced hearing loss

Aminoglycosides are a widely used class of antibacterials renowned for their effectiveness and broad antimicrobial spectrum.However,their use leads to irreversible hearing damage by causing apoptosis of hair cells as their direct target.In addition,the hearing damage caused by aminoglycosides involves damage of spiral ganglion neurons upon exposure.To investigate the mechanisms underlying spiral ganglion neuron degeneration induced by aminoglycosides,we used a C57BL/6J mouse model treated with kanamycin.We found that the mice exhibited auditory deficits following the acute loss of outer hair cells.Spiral ganglion neurons displayed hallmarks of pyroptosis and exhibited progressive degeneration over time.Transcriptomic profiling of these neurons showed significant upregulation of genes associated with inflammation and immune response,particularly those related to the NLRP3 inflammasome.Activation of the canonical pyroptotic pathway in spiral ganglion neurons was observed,accompanied by infiltration of macrophages and the release of proinflammatory cytokines.Pharmacological intervention targeting NLRP3 using Mcc950 and genetic intervention using NLRP3 knockout ameliorated spiral ganglion neuron degeneration in the injury model.These findings suggest that NLRP3 inflammasome-mediated pyroptosis plays a role in aminoglycoside-induced spiral ganglion neuron degeneration.Inhibition of this pathway may offer a potential therapeutic strategy for treating sensorineural hearing loss by reducing spiral ganglion neuron degeneration.

Evaluating foot reflexology as a proposed treatment for sensorineural hearing loss:A critical review

This editorial critically evaluates the application of foot reflexology as a treatment for sensorineural hearing loss(SNHL)in infants,as proposed in a case report published in the World of Clinical Cases.SNHL is a condition characterized by damage to the cochlea or the neural pathways that transmit auditory information to the brain.The etiology of SNHL is often complex,involving genetic mutations,prenatal factors,or perinatal insults.Reflexology,an alternative therapy involving the application of pressure to specific points on the feet,is based on the hypothesis that these points correspond to different organs and systems in the body,including the auditory system.However,the biological plausibility and clinical efficacy of foot reflexology in addressing SNHL lack empirical support.This editorial examines the pathophysiology of SNHL,assesses the clinical claims of reflexology practitioners,and emphasizes the necessity of evidence-based approaches in treating infant hearing loss.While complementary therapies may provide ancillary benefits,they should not supplant validated medical treatments in managing SNHL in infants.Further research is needed to evaluate the safety and efficacy of foot reflexology and other alternative therapies in pediatric audiology.

Acquired sensorineural hearing loss,oxidative stress,and microRNAs

Hearing loss is the third leading cause of human disability.Age-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health burden.Noise-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing loss.The etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental factors.Oxidative stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing loss.Short non-coding RNA sequences known as microRNAs(miRNAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic response.Sensory hair cell death is a central histopathological finding in sensorineural hearing loss.As these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing loss.Ovid EMBASE,Ovid MEDLINE,Web of Science Core Collection,and ClinicalTrials.gov databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRNAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical trials.Registe red clinical trials known to the senior author we re also assessed.A total of 222studies were thus identified.After excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text screening.This resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative review.MiRNAs miR-34a and miR-29b levels increase with age in mice.These miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/P GC-1α),SIRT1p53,and SIRT1/hypoxia-inducible factor 1-alpha signaling pathways resulting in increased apoptosis.Furthermore,hypoxia and oxidative stress had a similar adve rse apoptotic effect,which was inhibited by resve ratrol and a myocardial inhibitorassociated transcript,a miR-29b competing endogenous mRNA.Gentamicin reduced miR-182-5p levels and increased cochlear oxidative stress and cell death in mice-an effect that was corrected by inner ear stem cell-derived exosomes.There is ongoing work seeking to determine if these findings can be effectively translated to humans.

Integration of Electrical Properties and Polarization Loss Modulation on Atomic Fe–N‑RGO for Boosting Electromagnetic Wave Absorption

Developing effective strategies to regulate graphene’s conduction loss and polarization has become a key to expanding its application in the electromagnetic wave absorption(EMWA)field.Based on the unique energy band structure of graphene,regulating its bandgap and electrical properties by introducing heteroatoms is considered a feasible solution.Herein,metal-nitrogen doping reduced graphene oxide(M–N-RGO)was prepared by embedding a series of single metal atoms M–N_(4) sites(M=Mn,Fe,Co,Ni,Cu,Zn,Nb,Cd,and Sn)in RGO using an N-coordination atom-assisted strategy.These composites had adjustable conductivity and polarization to optimize dielectric loss and impedance matching for efficient EMWA performance.The results showed that the minimum reflection loss(RL_(min))of Fe–N-RGO reaches−74.05 dB(2.0 mm)and the maximum effective absorption bandwidth(EAB_(max))is 7.05 GHz(1.89 mm)even with a low filler loading of only 1 wt%.Combined with X-ray absorption spectra(XAFS),atomic force microscopy,and density functional theory calculation analysis,the Fe–N_(4) can be used as the polarization center to increase dipole polarization,interface polarization and defect-induced polarization due to d-p orbital hybridization and structural distortion.Moreover,electron migration within the Fe further leads to conduction loss,thereby synergistically promoting energy attenuation.This study demonstrates the effectiveness of metal-nitrogen doping in regulating the graphene′s dielectric properties,which provides an important basis for further investigation of the loss mechanism.

Foot reflexology in autoimmune diseases:Effectiveness and mechanisms

Foot reflexology(FR)is a Chinese-originated and non-invasive complementary therapy increasingly used by functional,alternative and para-medical professionals.Enhance attempts are made to study FR in non-functional organic conditions.The present invited Editorial discusses the application of FR in autoimmune diseases(AD),highlighting a few successful studies demonstrating symptomatic relief and objective improvements.Despite promising results,the FR domain remains under-investigated and an urgent need to confirm and understand the effect of FR in chronic diseases,including AD,is highly recommended.

Apelin-13抑制巨噬细胞M1极化缓解全身炎症性骨丢失

背景:Apelin-13因具有抗炎和抗氧化等生物活性,在神经炎症、心血管损伤和肺炎等临床常见疾病中发挥着有效的治疗作用,然而对于Apelin-13在治疗炎症性骨丢失中是否同样具有良好的疗效目前尚无相关基础研究。目的:探究Apelin-13对炎症性骨丢失的治疗作用及其机制,以期探究治疗炎症性骨丢失的潜在药物。方法:①体外实验:将RAW264.7细胞分为3组:对照组,脂多糖组和治疗组。对照组只加入DMEM完全培养基;脂多糖组加入脂多糖(100 ng/mL)诱导炎症DMEM培养基;治疗组加入10 nmol/L Apelin-13+脂多糖诱导炎症DMEM培养基。诱导炎症24 h后,使用Western Blot检测M1型巨噬细胞的标志蛋白诱导型一氧化氮合酶和CD86的表达,并使用细胞免疫荧光染色检测诱导型一氧化氮合酶的表达。并在对照组、脂多糖组和治疗组中同时加入等量的核因子κB受体活化因子配体(50 ng/mL)诱导破骨细胞,诱导6 d后使用抗酒石酸酸性磷酸酶染色和F-actin染色评估破骨细胞诱导的结果。②体内实验:将18只C57BL/6雄性小鼠随机分为3组:假手术组、脂多糖组、治疗组。假手术组连续1周在小鼠腹腔内注射0.1 mL的PBS;脂多糖组注射0.1 mL含脂多糖(5 mg/kg)的PBS稀释液;治疗组注射0.1 mL含脂多糖(5 mg/kg)+Apelin-13(100μg/kg)的PBS稀释液。3组小鼠连续腹腔注射7 d,于第8天处死小鼠,收集每只小鼠的2个股骨,一半进行micro-CT扫描和骨参数分析,另一半进行苏木精-伊红染色。结果与结论:①体外实验:Western Blot结果显示,脂多糖组诱导型一氧化氮合酶和CD86的表达较对照组明显增多,而Apelin-13能够显著抑制脂多糖诱导的巨噬细胞M1极化,细胞免疫荧光的结果也显示治疗组诱导型一氧化氮合酶的表达较脂多糖组减少,同时抗酒石酸酸性磷酸酶染色和F-actin染色结果显示Apelin-13抑制脂多糖诱导的破骨细胞异常活化及骨吸收能力。②体内实验:micro-CT结果显示全身炎性导致股骨远端骨质出现明显丢失,而Apelin-13则能够显著抑制骨质的流失,苏木精-伊红染色结果也表明Apelin-13能够有效缓解炎症诱导的小鼠股骨远端骨质流失。③结果表明:Apelin-13能够通过抑制巨噬细胞M1极化,抑制破骨细胞的异常激活和骨吸收能力,缓解全身炎症诱导的骨丢失。

Is it possible to foot reflexology for infants with sensorineural hearing loss?

Foot reflexology is a non-invasive and safe complementary therapy that works by massaging the reflex zones of the feet and exerts systemic or whole-body regulation through meridian nerve conduction.This therapy is commonly used in the treatment of various conditions such as autism and Parkinson's disease.However,there is limited reporting on the use of foot reflexology therapy for infants with sensorineural hearing loss(SNHL).Currently,there is no definitive conclusion on how foot reflexology therapy can influence hearing.This editorial holds some guiding significance regarding this clinical issue.The aim is to present physiological evidence of how foot reflexology therapy can impact infants with SNHL,thereby enhancing clinician’s awareness of foot reflexology in treating infants with SNHL.

Physical rehabilitation for sensorineural hearing loss in childhood:Progress and challenges

Early intervention for sensorineural hearing loss(SNHL)in childhood is crucial for auditory and language development.In recent years,innovative auditory stimulation techniques and speech therapy strategies,such as middle ear implants,cochlear implants,auditory brainstem implants,and midbrain implants,have provided new avenues for improving patient outcomes.Additionally,basic research advancements in cell reprogramming and regeneration,stem cell therapy,and targeted drug delivery offer promising approaches to meet the individualized needs of children with SNHL.However,many challenges and unresolved issues remain in the treatment of SNHL.This article comments on the case report,which describes a female pediatric patient with SNHL who underwent foot reflexology which led to the normalization of hearing thresholds.Reflexology is considered to have potential benefits in physical rehabilitation,but its efficacy in hearing restoration requires further scientific validation through rigorous clinical trials and large-scale prospective studies.

Herpes simplex virus 2-induced aseptic meningitis presenting with sudden deafness:A case report

BACKGROUND Aseptic meningitis is defined as meningeal inflammation caused by various etio-logies with negative cerebrospinal fluid(CSF)bacterial culture.The most common etiologies are viruses[enteroviruses,arboviruses,and herpes simplex virus type 2(HSV-2)].Aseptic meningitis can have various presentations,including sensori-neural deafness.While sensorineural deafness from mumps meningoencephalitis has been reported,cases of HSV-2-induced hearing loss are rare.Herein,we re-port a case of HSV-2-induced meningitis that presented with sudden deafness.CASE SUMMARY A 68-year-old man experienced a profound sudden onset of left-sided hearing loss for one day.Pure-tone audiograms demonstrated sudden left-sided sensorineural hearing loss(thresholds 80-90 dB).After treatment with high-dose steroids for 1 week,he experienced an acute consciousness change with left hemiparesis.The laboratory data showed no significant abnormalities.Brain computed tomography without contrast and magnetic resonance imaging revealed no intracranial hemo-rrhage or obvious brain lesion.The CSF analysis and the Multiplex PCR panels showed HSV-2 positivity.Hence,under the diagnosis of herpes meningoenceph-alitis,acyclovir was prescribed and his symptoms gradually resolved.CONCLUSION This case report further demonstrates that a viral infection could be a cause of sudden sensorineural hearing loss.

墨鱼干碱水-纯水组合复水工艺优化及复水前后质构特性

目的:探究墨鱼干复水最优工艺参数及其复水前后的质构变化。方法:通过先用碱水后用纯水的组合复水方式进行处理,以复水率和蛋白损失率为优化指标进行条件优化,随后对墨鱼干复水前后的质构特性以及蛋白质二级结构、组织形态等相关指标进行分析。结果:碱水处理墨鱼干的最佳条件为:碳酸钠浓度0.50%、时间2.0 h、温度50℃、料液比1:20 g/mL;在此基础上,进行纯水处理的最佳条件为:时间1.0 h、温度50℃、料液比为1:20 g/mL。两步处理后,墨鱼干的复水率为261.10%±7.10%,蛋白损失率为16.80%±0.74%。复水处理使墨鱼干的硬度、胶着性和咀嚼性显著降低,而弹性则显著上升(P<0.05),并使肌原纤维蛋白的结构折叠,且肌纤维的间隙增加。结论:本研究明确墨鱼干最优复水参数并改善其质构特性,为墨鱼干的高质化加工利用提供理论参考。

Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology

Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy patients.These aggregates alter protein-protein interactions and compromise transcriptional activity.In this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic factor.Overexpressio n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor aggregation.Conversely.knocking down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor aggregation.Our findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy.