ON MONOTONE TRAVELING WAVES FOR NICHOLSON'S BLOWFLIES EQUATION WITH DEGENERATE p-LAPLACIAN DIFFUSION

We study the existence and stability of monotone traveling wave solutions of Nicholson's blowflies equation with degenerate p-Laplacian diffusion.We prove the existence and nonexistence of non-decreasing smooth traveling wave solutions by phase plane analysis methods.Moreover,we show the existence and regularity of an original solution via a compactness analysis.Finally,we prove the stability and exponential convergence rate of traveling waves by an approximated weighted energy method.

Nondegenerate Soliton Solutions of(2+1)-Dimensional Multi-Component Maccari System

For a multi-component Maccari system with two spatial dimensions,nondegenerate one-soliton and two-soliton solutions are obtained with the bilinear method.It can be seen by drawing the spatial graphs of nondegenerate solitons that the real component of the system shows a cross-shaped structure,while the two solitons of the complex component show a multi-solitoff structure.At the same time,the asymptotic analysis of the interaction behavior of the two solitons is conducted,and it is found that under partially nondegenerate conditions,the real and complex components of the system experience elastic collision and inelastic collision,respectively.

Existence of Entropy Solution for Degenerate Parabolic-Hyperbolic Problem Involving p(x)-Laplacian with Neumann Boundary Condition

We consider a strongly non-linear degenerate parabolic-hyperbolic problem with p(x)-Laplacian diffusion flux function. We propose an entropy formulation and prove the existence of an entropy solution.

外泌体来源非编码RNA对骨关节炎微环境的作用及临床应用进展

背景:骨关节炎是一种常见的关节退行性疾病,其发生发展的病因学机制尚不清楚。早期骨关节炎的及时诊治十分重要,目前尚无确切有效的方法。外泌体来源广泛,其中包含非编码RNA(Non-coding RNAs,ncRNAs),如微小RNAs、环状RNAs和长链非编码RNAs。外泌体ncRNAs可直接从原始细胞递送至邻近或远程细胞,通过细胞间通讯调节细胞活性,在重塑骨关节微环境中具有重要的调控作用。目的:总结外泌体来源ncRNAs对骨关节炎关节内微环境的干预作用,以及在临床应用中取得的进展,阐明其在骨关节炎诊治方面的潜力。方法:以“exosomes,non-coding RNA,osteoarthritis,application,signal pathway,synovial fluid,cartilage cells,cartilage matrix,subchondral bone,mechanism”为检索词在PubMed数据库中进行检索,最终纳入66篇相关文献进行综述分析。结果与结论:①外泌体来源ncRNAs在骨关节炎的发病过程中对关节内微环境具有重要调控作用,主要体现在外泌体ncRNAs调控关节内炎症反应、软骨细胞及软骨基质的退化,软骨下骨重塑和细胞间通讯。②外泌体中的ncRNAs可以作为骨关节炎的生物标志物,帮助骨关节炎的早期诊断和监测疾病进展与预后。③外泌体ncRNAs可作为骨关节炎的治疗靶点,外泌体携带miRNAs递送到关节的软骨细胞及软骨基质,发挥调控作用。④外泌体ncRNAs可以通过调控基因表达、促进细胞间通讯,提高软骨组织工程的效果,修复或再生受损软骨。⑤未来研究者应继续发掘外泌体来源ncRNAs对骨关节炎的干预机制,并可结合最新软骨组织工程的研究成果应用到临床之中,这将有效帮助解决骨关节炎患者的病痛。

椎间盘退变中的力学信号转导蛋白

背景:近年来的研究表明椎间盘退变与异常压力负荷密切相关,而力学信号转导蛋白在其中发挥了关键作用。目的:探讨力学信号转导蛋白在异常机械力刺激诱导椎间盘退变的力化学信号换能过程中发挥的作用及机制,总结目前靶向力学信号延缓椎间盘退变的治疗策略。方法:以“椎间盘,髓核,纤维环,软骨终板,细胞,力,信号转导,蛋白,生物力学”为中文检索词,以“intervertebral disc,nucleus pulposus,annulus fibrosus,cartilaginous endplate,cell,mechanical stimulation,signal transduction,protein,biomechanics”为英文检索词,检索PubMed、CNKI数据库中的相关文献,最终纳入88篇文献进行综述。结果与结论:椎间盘细胞能通过多种力学信号转导蛋白感知外界机械刺激并将其转化为细胞内生物学反应,这些转导蛋白主要包括细胞外基质中的胶原蛋白、细胞膜表面受体(如整合素及离子通道)、细胞骨架结构蛋白等。力学信号转导蛋白调控力化学信号换能的过程主要包括多个通路的激活,如PI3K/AKT信号通路、核因子κB信号通路、Ca^(2+)/Calpain2/Caspase3通路等。力学信号转导蛋白在椎间盘细胞机械信号换能中发挥了关键作用,这些蛋白表达异常或由此导致的细胞外基质环境改变会破坏椎间盘细胞的力学平衡,引发椎间盘退变。深入研究椎间盘细胞力学信号转导蛋白的表达及调控机制,寻找关键的病理环节和治疗靶点,对开发椎间盘退变治疗策略具有重要意义,目前靶向力学信号延缓椎间盘退变的策略主要包括对转导蛋白的调控、对细胞外基质的改良等,然而这方面研究还处于初级阶段,随着研究的不断深入,力学信号转导蛋白调控椎间盘退变有望实现新的突破。

The Solvability of the Degenerate Differential Systems with Delay

In this paper we study the degenerate differential system with delay:E(t)=Ax(t)+Bx(t-1)+f(t),give the canonical form of this systems and study this form of degeneration system with delay,have some results for the solvability of such systems and the uniqueness of their solutions.

超声引导下针刀松解黄韧带对兔退变腰椎间盘整合素α5、β1表达的影响

背景:针刀松解黄韧带可有效改善腰椎退行性患者的症状,超声引导可增加针刀松解的精准性,但针刀松解黄韧带后对退变椎间盘的具体影响及可能的机制尚待明确。目的:探讨超声引导下针刀松解黄韧带对兔腰椎间盘退变的作用。方法:取24只新西兰兔,采用随机数字表法分为对照组(n=6)与造模组(n=18)。造模组采用横断L5/6、L6/7节段棘上、棘间韧带并保持站立姿势对腰椎施加轴向载荷的方式建立兔腰椎间盘退变模型,造模成功后再随机分为模型组、超声针刀组、假针刀组,每组6只,超声针刀组在超声引导下使用针刀松解L7/S1右侧黄韧带,假针刀组针刀入路同超声针刀组,但不松解黄韧带,1次/周,共4次。针刀干预后30 d,利用MRI观察L7/S1椎间盘髓核信号强度变化,苏木精-伊红染色观察L7/S1椎间盘形态变化,免疫组化染色检测L7/S1椎间盘髓核内Ⅰ,Ⅱ型胶原表达,RT-PCR、Western Blot检测L7/S1椎间盘中整合素α5、β1、p38、核因子κB的表达。结果与结论:①MRI成像显示,模型组兔椎间盘髓核呈灰-黑色,髓核灰度值明显低于对照组(P<0.01);超声针刀组兔椎间盘髓核亮度较模型组升高,髓核灰度值高于模型组(P<0.01);②苏木精-伊红染色显示,模型组髓核形状不规则,髓核细胞数量减少,细胞外基质被压缩,纤维环破裂,终板结构与边界不清,软骨细胞排列紊乱;与模型组相比,超声针刀组髓核细胞数量增多,纤维环破裂情况有改善,软骨终板细胞排列较为规则;③免疫组化染色显示,与对照组比较,模型组髓核内Ⅰ型胶原阳性表达增加(P<0.01),Ⅱ型胶原阳性表达减少(P<0.01);与模型组比较,超声针刀组髓核内Ⅰ型胶原阳性表达减少(P<0.01),Ⅱ型胶原阳性表达增加(P<0.01);④RT-PCR、Western Blot检测显示,与对照组比较,模型组兔椎间盘中整合素α5、整合素β1、p38、核因子κB的mRNA与蛋白表达均升高(P<0.01);与模型组比较,超声针刀组兔椎间盘中整合素α5、整合素β1、p38、核因子κB的mRNA与蛋白表达均降低(P<0.01);⑤结果表明,超声引导下针刀松解黄韧带可改善兔腰椎间盘退变程度,该作用与通过调控整合素α5、β1表达、抑制p38和核因子κB表达有关。

Polyethylene glycol has immunoprotective effects on sciatic allografts, but behavioral recovery and graft tolerance require neurorrhaphy and axonal fusion

Behavioral recovery using(viable)peripheral nerve allografts to repair ablation-type(segmental-loss)peripheral nerve injuries is delayed or poor due to slow and inaccurate axonal regeneration.Furthermore,such peripheral nerve allografts undergo immunological rejection by the host immune system.In contrast,peripheral nerve injuries repaired by polyethylene glycol fusion of peripheral nerve allografts exhibit excellent behavioral recovery within weeks,reduced immune responses,and many axons do not undergo Wallerian degeneration.The relative contribution of neurorrhaphy and polyethylene glycol-fusion of axons versus the effects of polyethylene glycol per se was unknown prior to this study.We hypothesized that polyethylene glycol might have some immune-protective effects,but polyethylene glycol-fusion was necessary to prevent Wallerian degeneration and functional/behavioral recovery.We examined how polyethylene glycol solutions per se affect functional and behavioral recovery and peripheral nerve allograft morphological and immunological responses in the absence of polyethylene glycol-induced axonal fusion.Ablation-type sciatic nerve injuries in outbred Sprague–Dawley rats were repaired according to a modified protocol using the same solutions as polyethylene glycol-fused peripheral nerve allografts,but peripheral nerve allografts were loose-sutured(loose-sutured polyethylene glycol)with an intentional gap of 1–2 mm to prevent fusion by polyethylene glycol of peripheral nerve allograft axons with host axons.Similar to negative control peripheral nerve allografts not treated by polyethylene glycol and in contrast to polyethylene glycol-fused peripheral nerve allografts,animals with loose-sutured polyethylene glycol peripheral nerve allografts exhibited Wallerian degeneration for all axons and myelin degeneration by 7 days postoperatively and did not recover sciatic-mediated behavioral functions by 42 days postoperatively.Other morphological signs of rejection,such as collapsed Schwann cell basal lamina tubes,were absent in polyethylene glycol-fused peripheral nerve allografts but commonly observed in negative control and loose-sutured polyethylene glycol peripheral nerve allografts at 21 days postoperatively.Loose-sutured polyethylene glycol peripheral nerve allografts had more pro-inflammatory and less anti-inflammatory macrophages than negative control peripheral nerve allografts.While T cell counts were similarly high in loose-sutured-polyethylene glycol and negative control peripheral nerve allografts,loose-sutured polyethylene glycol peripheral nerve allografts expressed some cytokines/chemokines important for T cell activation at much lower levels at 14 days postoperatively.MHCI expression was elevated in loose-sutured polyethylene glycol peripheral nerve allografts,but MHCII expression was modestly lower compared to negative control at 21 days postoperatively.We conclude that,while polyethylene glycol per se reduces some immune responses of peripheral nerve allografts,successful polyethylene glycol-fusion repair of some axons is necessary to prevent Wallerian degeneration of those axons and immune rejection of peripheral nerve allografts,and produce recovery of sensory/motor functions and voluntary behaviors.Translation of polyethylene glycol-fusion technologies would produce a paradigm shift from the current clinical practice of waiting days to months to repair ablation peripheral nerve injuries.

Calcium channels caught in peripheral glia’s tug-of-war on axon regeneration in Drosophila

Neural damage or degeneration is at the crux of many diseases,and treatment of these diseases will require the development of therapeutics to enhance and guide neural regeneration.Both intrinsic and extrinsic factors dictate a neuron’s ability to regenerate,and the combination of these factors results in the great regenerative capacity of the peripheral nervous system(PNS)and the poor regenerative capacity of the central nervous system(CNS)following injury.At the core of a neuron’s function is its ability to relay electrochemical signals,and a neuron’s excitability is a key factor in its ability to regenerate.Recent works have focused on the changes in neuronal electrophysiological properties,firing patterns,and ion flux after injury,which differentially activate signaling pathways at the core of regeneration.The role of glia in neuron regeneration has long been studied.

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.

Glial response in the midcingulate cortex in Huntington’s disease

Huntington’s disease(HD)is a genetic disease characterized by the progressive degeneration of the striatum and cortex.Patients can present with a variety of symptoms that can broadly be classified into motor symptoms,inclusive of choreatic movements and rigidity,mood and psychiatric symptoms,such as depression and apathy,and cognitive symptoms,such as cognitive decline.The causal mutation underlying HD results from an expansion of a CAG repeat sequence on the IT15 gene,resulting in the formation and accumulation of a mutant huntingtin protein.

Role of glutathione transferase in phase separation of FUS and TAF15 in neurons

Amyotrophic lateral sclerosis(ALS)is a progressive neurodegenerative disorder characterized by the degeneration of motor neurons in the brain and spinal cord,leading to muscle weakness,paralysis,and ultimately death(Cleveland and Rothstein,2001).Frontotemporal lobar degeneration(FTLD)is a neurodegenerative disease affecting the frontal and temporal lobes of the brain,leading to changes in behavior,personality,and language(Van Langenhove et al.,2012).Both ALS and FTLD are classified as proteinopathies in which abnormal protein aggregation and accumulation in neurons contribute to the disease pathogenesis.Fused in sarcoma(FUS)is a DNA/RNA-binding protein involved in various cellular processes,including transcriptional regulation,RNA splicing,and DNA repair.Mutations in the FUS gene have been linked to familial ALS,highlighting the importance of FUS in the disease pathogenesis(Vance et al.,2009).In ALS and FTLD,aberrant post-translational modifications(PTMs)of FUS,such as phosphorylation,acetylation,and methylation,have been implicated in the promotion of FUS aggregation and neurotoxicity(Choi et al.,2023).Therefore,understanding the regulatory mechanisms of FUS PTMs is crucial for developing targeted therapies against these diseases.

Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower extremities.HSP is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

Monogenic gene therapy for glaucoma and optic nerve injury

The prevalence of glaucoma, the second leading cause of global blindness, is increasing due to aging populations. In glaucoma, degeneration of the optic nerve and retinal ganglion cells(RGCs) causes visual field defects and eventual blindness.

Mechanisms behind elevated serum levels of plasminogen activator inhibitor-1 in frontotemporal lobar degeneration

Frontotemporal lobar degeneration(FTLD)is a form of progressive dementia characterized by degeneration of the frontal and temporal lobes of the brain.This pathology involves a series of cognitive,behavioral,and neurological symptoms that influence personality,decision-making ability,and language.

A-kinase anchoring protein-mediated compartmentalization of pro-survival signaling in the retina

The retina plays a fundamental role in the process of vision,serving as the primary interface between external visual stimuli and the central nervous system.Because the retina is exposed to a variety of environmental stresses and deleterious insults,it is susceptible to a spectrum of pathological conditions that can detrimentally affect vision.This often leads to irreversible vision loss due to the injury of specific cell types.For instance,inherited retinal degeneration and age-related macular degeneration can lead to the death of photoreceptors,while conditions like glaucoma and optic nerve injury can result in the loss of ganglion cells.The precise pathological mechanisms driving retinal degeneration remain largely elusive,although research utilizing mouse models suggests that disruptions in intracellular signal transduction pathways may play a pivotal role.Signaling pathways within the retina orchestrate various aspects of retinal physiology,including phototransduction,synaptic transmission,and neuronal survival.

Functions of nuclear factor Y in nervous system development,function and health

Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 years,research has revealed that the nuclear factor Y complex controls many aspects of brain development,including differentiation,axon guidance,homeostasis,disease,and most recently regeneration.However,a complete understanding of transcriptional regulatory networks,including how the nuclear factor Y complex binds to specific CCAAT boxes to perform its function remains elusive.In this review,we explore the nuclear factor Y complex’s role and mode of action during brain development,as well as how genomic technologies may expand understanding of this key regulator of gene expression.

The gut-eye axis:from brain neurodegenerative diseases to age-related macular degeneration

Age-related macular degeneration is a serious neurodegenerative disease of the retina that significantly impacts vision.Unfortunately,the specific pathogenesis remains unclear,and effective early treatment options are consequently lacking.The microbiome is defined as a large ecosystem of microorganisms living within and coexisting with a host.The intestinal microbiome undergoes dynamic changes owing to age,diet,genetics,and other factors.Such dysregulation of the intestinal flora can disrupt the microecological balance,resulting in immunological and metabolic dysfunction in the host,and affecting the development of many diseases.In recent decades,significant evidence has indicated that the intestinal flora also influences systems outside of the digestive tract,including the brain.Indeed,several studies have demonstrated the critical role of the gut-brain axis in the development of brain neurodegenerative diseases,including Alzheimer’s disease and Parkinson’s disease.Similarly,the role of the“gut-eye axis”has been confirmed to play a role in the pathogenesis of many ocular disorders.Moreover,age-related macular degeneration and many brain neurodegenerative diseases have been shown to share several risk factors and to exhibit comparable etiologies.As such,the intestinal flora may play an important role in age-related macular degeneration.Given the above context,the present review aims to clarify the gut-brain and gut-eye connections,assess the effect of intestinal flora and metabolites on age-related macular degeneration,and identify potential diagnostic markers and therapeutic strategies.Currently,direct research on the role of intestinal flora in age-related macular degeneration is still relatively limited,while studies focusing solely on intestinal flora are insufficient to fully elucidate its functional role in age-related macular degeneration.Organ-on-a-chip technology has shown promise in clarifying the gut-eye interactions,while integrating analysis of the intestinal flora with research on metabolites through metabolomics and other techniques is crucial for understanding their potential mechanisms.

Polyethylene glycol fusion repair of severed sciatic nerves accelerates recovery of nociceptive sensory perceptions in male and female rats of different strains

Successful polyethylene glycol fusion(PEG-fusion)of severed axons following peripheral nerve injuries for PEG-fused axons has been reported to:(1)rapidly restore electrophysiological continuity;(2)prevent distal Wallerian Degeneration and maintain their myelin sheaths;(3)promote primarily motor,voluntary behavioral recoveries as assessed by the Sciatic Functional Index;and,(4)rapidly produce correct and incorrect connections in many possible combinations that produce rapid and extensive recovery of functional peripheral nervous system/central nervous system connections and reflex(e.g.,toe twitch)or voluntary behaviors.The preceding companion paper describes sensory terminal field reo rganization following PEG-fusion repair of sciatic nerve transections or ablations;howeve r,sensory behavioral recovery has not been explicitly explored following PEG-fusion repair.In the current study,we confirmed the success of PEG-fusion surgeries according to criteria(1-3)above and more extensively investigated whether PEG-fusion enhanced mechanical nociceptive recovery following sciatic transection in male and female outbred Sprague-Dawley and inbred Lewis rats.Mechanical nociceptive responses were assessed by measuring withdrawal thresholds using von Frey filaments on the dorsal and midplantar regions of the hindpaws.Dorsal von Frey filament tests were a more reliable method than plantar von Frey filament tests to assess mechanical nociceptive sensitivity following sciatic nerve transections.Baseline withdrawal thresholds of the sciatic-mediated lateral dorsal region differed significantly across strain but not sex.Withdrawal thresholds did not change significantly from baseline in chronic Unoperated and Sham-operated rats.Following sciatic transection,all rats exhibited severe hyposensitivity to stimuli at the lateral dorsal region of the hindpaw ipsilateral to the injury.However,PEG-fused rats exhibited significantly earlier return to baseline withdrawal thresholds than Negative Control rats.Furthermore,PEG-fused rats with significantly improved Sciatic Functional Index scores at or after 4 weeks postoperatively exhibited yet-earlier von Frey filament recove ry compared with those without Sciatic Functional Index recovery,suggesting a correlation between successful PEG-fusion and both motor-dominant and sensory-dominant behavioral recoveries.This correlation was independent of the sex or strain of the rat.Furthermore,our data showed that the acceleration of von Frey filament sensory recovery to baseline was solely due to the PEG-fused sciatic nerve and not saphenous nerve collateral outgrowths.No chronic hypersensitivity developed in any rat up to 12 weeks.All these data suggest that PEG-fusion repair of transection peripheral nerve injuries co uld have important clinical benefits.

Age-related driving mechanisms of retinal diseases and neuroprotection by transcription factor EB-targeted therapy

Retinal aging has been recognized as a significant risk factor for various retinal disorders,including diabetic retinopathy,age-related macular degeneration,and glaucoma,following a growing understanding of the molecular underpinnings of their development.This comprehensive review explores the mechanisms of retinal aging and investigates potential neuroprotective approaches,focusing on the activation of transcription factor EB.Recent meta-analyses have demonstrated promising outcomes of transcription factor EB-targeted strategies,such as exercise,calorie restriction,rapamycin,and metformin,in patients and animal models of these common retinal diseases.The review critically assesses the role of transcription factor EB in retinal biology during aging,its neuroprotective effects,and its therapeutic potential for retinal disorders.The impact of transcription factor EB on retinal aging is cell-specific,influencing metabolic reprogramming and energy homeostasis in retinal neurons through the regulation of mitochondrial quality control and nutrient-sensing pathways.In vascular endothelial cells,transcription factor EB controls important processes,including endothelial cell proliferation,endothelial tube formation,and nitric oxide levels,thereby influencing the inner blood-retinal barrier,angiogenesis,and retinal microvasculature.Additionally,transcription factor EB affects vascular smooth muscle cells,inhibiting vascular calcification and atherogenesis.In retinal pigment epithelial cells,transcription factor EB modulates functions such as autophagy,lysosomal dynamics,and clearance of the aging pigment lipofuscin,thereby promoting photoreceptor survival and regulating vascular endothelial growth factor A expression involved in neovascularization.These cell-specific functions of transcription factor EB significantly impact retinal aging mechanisms encompassing proteostasis,neuronal synapse plasticity,energy metabolism,microvasculature,and inflammation,ultimately offering protection against retinal aging and diseases.The review emphasizes transcription factor EB as a potential therapeutic target for retinal diseases.Therefore,it is imperative to obtain well-controlled direct experimental evidence to confirm the efficacy of transcription factor EB modulation in retinal diseases while minimizing its risk of adverse effects.