From mice to humans:a need for comparable results in mammalian neuroplasticity

Brain plasticity-A universal tool with many variations:The study of brain plasticity has been gaining interest since almost a century and has now reached a huge amount of information(>80,000 results in PubMed).Overall,different types of plasticity,including stem cell-driven genesis of new neurons(adult neurogenesis),cells in arrested maturation(dormant neurons),neuro-glial and synaptic plasticity,can coexist and contribute to grant plastic changes in the brain,from a cellular to system level(Benedetti and Couillard-Despres,2022;Bonfanti et al.,2023).

Contribution of mechanical forces to structural synaptic plasticity:insights from 3D cellular motility mechanisms

Cells,tissues,and organs are constantly subjected to the action of mechanical forces from the extracellular environment-and the nervous system is no exception.Cell-intrinsic properties such as membrane lipid composition,abundance of mechanosensors,and cytoskeletal dynamics make cells more or less likely to sense these forces.Intrinsic and extrinsic cues are integrated by cells and this combined information determines the rate and dynamics of membrane protrusion growth or retraction(Yamada and Sixt,2019).Cell protrusions are extensions of the plasma membrane that play crucial roles in diverse contexts such as cell migration and neuronal synapse formation.In the nervous system,neurons are highly dynamic cells that can change the size and number of their pre-and postsynaptic elements(called synaptic boutons and dendritic spines,respectively),in response to changes in the levels of synaptic activity through a process called plasticity.Synaptic plasticity is a hallmark of the nervous system and is present throughout our lives,being required for functions like memory formation or the learning of new motor skills(Minegishi et al.,2023;Pillai and Franze,2024).

Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. Moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased complexity and restructuring of neural network structures, as well as the addition of new granule granule cells that aid in olfactory adaptation. Additionally, the manuscript underscores the importance of employing precise methodologies to elucidate the specific roles of adult neurogenesis amidst conflicting data and varying experimental paradigms. Understanding these processes is essential for gaining insights into the complexities of olfactory function and behavior.

The interaction between KIF21A and KANK1 regulates dendritic morphology and synapse plasticity in neurons

Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and memory.Kinesin-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains unknown.In this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative spines.Furthermore,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic plasticity.Knockdown of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and talin1.Knocking down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive abilities.Taken together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function.

Practice patterns among ophthalmic surgeons in treating concomitant oculoplastic conditions in preoperative period:A questionnaire-based study

BACKGROUND Addressing oculoplastic conditions in the preoperative period ensures both the safety and functional success of any ophthalmic procedure.Some oculoplastic conditions,like nasolacrimal duct obstruction,have been extensively studied,whereas others,like eyelid malposition and thyroid eye disease,have received minimal or no research.AIM To investigate the current practice patterns among ophthalmologists while treating concomitant oculoplastic conditions before any subspecialty ophthalmic intervention.METHODS A cross-sectional survey was disseminated among ophthalmologists all over India.The survey included questions related to pre-operative evaluation,anaesthetic and surgical techniques preferred,post-operative care,the use of adjunctive therapies,and patient follow-up patterns.RESULTS A total of 180 ophthalmologists responded to the survey.Most practitioners(89%)felt that the ROPLAS test was sufficient during pre-operative evaluation before any subspecialty surgery was advised.The most common surgical techniques employed were lacrimal drainage procedures(Dacryocystorhinostomy)(63.3%),eyelid malposition repair(36.9%),and ptosis repair(58.7%).Post-operatively,47.7%of respondents emphasized that at least a 4-week gap should be maintained after lacrimal drainage procedures and eyelid surgeries.Sixty-seven percent of ophthalmologists felt that topical anaesthetic procedures should be preferred while performing ocular surgeries in thyroid eye disease patients.CONCLUSION Approximately 50%of ophthalmologists handle prevalent oculoplastic issues themselves,seeking the expertise of an oculoplastic surgeon under particular conditions.Many ophthalmologists still favor using ROPLAS as a preliminary screening method before proceeding with cataract surgery.Eyelid conditions and thyroid eye disease are not as commonly addressed before subspecialty procedures compared to issues like nasolacrimal duct obstruction and periocular infections.

Microplastic and nanoplastic exposure and risk of diabetes mellitus

The issue of plastic pollutants has become a growing concern.Both microplastics(MPs)(particle size<5 mm)and nanoplastics(NPs)(particle size<1μm)can cause DNA damage,cytotoxicity,and oxidative stress in various organisms.The primary known impacts of microplastic/nanoplastic are observed in the liver and respiratory system,leading to hepatotoxicity and chronic obstructive pulmonary disease.Although research on the effects of MPs and NPs on diabetes is still in its early stages,there are potential concerns.This editorial highlights the risk to diabetics from co-exposure to contaminants and MPs/NPs,supported by evidence from animal studies and the various chemical compositions of MPs/NPs.

RIGID-PLASTIC/RIGID-VISCOPLASTIC FEM BASED ON LINEAR PROGRAMMING—THEORETICAL MODELING AND APPLICATION FOR AXISYMMETRICAL PROBLEMS

Compared with the traditional rigid plastic/rigid viscoplastic(RP/RVP) FEM(based on iteration solution),RP/RVP FEM based on linear programming (LP) has some remarkable advantages,such as it's free of convergence problem and its convenience in contact,rigid zone,and friction force treatment.The numerical model of RP/RVP FEM based on LP for axisymmetrical metal forming simulation is studied,and some related key factors and its treatment methods in formulation of constraint condition are proposed.Some solution examples are provided to validate its accuracy and efficiency.

EFFECT OF WALL SLIP ON SQUEEZE FLOW OF RIGID-PLASTIC MEDIA BETWEEN PARALLEL DISK

The squeeze flow of a rigid-plastic medium between parallel disks is considered for small gaps with partial wall slip. The stress distribution and the squeeze force between parallel disks of a rigid-plastic medium with the following four diferent slip boundary conditions are obtained. (1) The Coulombic friction condition is applied, and the stress distribution on the wall is derived, which is linear or exponential distribution in the no-slip area or slip area. (2) It is assumed that the slip velocity at the disks increases linearly with the radius up to the rim slip velocity, with the stress distribution and the squeeze force gained. (3) The assumption that the slip velocity at the disks is related to the shear stress component is used, with the stress distribution and the squeeze force obtained, which is equivalent to the result given in (2). (4) Rational velocity components are introduced, and the stress distribution is satisfed.

Three Dimension Rigid-plastic Finite Element Simulation for Two-Roll Cross-wedge Rolling Process

Cross-wedge rolling (CWR) is a metal process of ro ta ry forming. To produce a part, one cylindrical billet should be placed between t wo counterrotating and wedge-shape dies, which move tangentially relative each other. The billet suffers plastic deformation (essentially, localized compressio n) during its rotation between the rotating dies. Compared to other numerical si mulation methods, the finite element method (FEM) has advantages in solving gene ral problems with complex shapes of the formed parts. In cross-wedge rolling, t here are four stages in the workpiece deformation process, namely knifing, guidi ng, stretching and sizing stage. It is time-consuming and expensive to design t he CWR process by trial and error method. The application of numerical simul ation for the CWR process will help engineers to efficiently improve the process development. Tselikov, Hayama, Jain and Kobayashi, and Higashimo applied the sl ip-line theory in study of CWR process analysis. Zb.pater studied CWR process i ncluding upsetting by upper-bound method. The above numerical simulation were b ased on the two-dimensional plain-strain assumption ignored the metal flow in workpiece axial direction. Therefore, the complex three-dimensional stress and deformation involved in CWR processes were not presented. Compared to other nume rical simulation methods, the finite element method (FEM) has advantages in solv ing general problems with complex shapes of the formed parts. As yet, a few 3-D finite element simulation studies on CWR process have been reported in literatu res. In this paper, the process of cross wedge rolling (CWR) has been simulated and analyzed by 3D rigid-plastic finite element method. Considering the charact eristic of CWR, the static implicit FEM program is selected. The models proposed in this study uses the commercial code DEFORM 3D to simulate the CWR process. T his is an implicit Lagrangian finite element code, which includes many new enhan cements functions. A new method of utilizing multiple processors using the MPI s tandard has been implemented. Automatic switching between the two different defo rmation solvers (Sparse Solver and Conjugate Gradient Solver) has also been impl emented in order to increase the speed of simulations. In this paper, all stages in CWR process are simulated to be able to closely understand and analyze the a ctual CWR process. For simulating all forming stages in CWR process, the dynam ic adaptive remeshing technology for tetrahedral solid elements was applied. T he stress distributions in cross section of forming workpiece are analyzed to in terpret fracture or rarefaction in the center of workpiece. Authors also analyze d the time-torque curve and the laws of load changing.

ADAPTIVE RIGID-PLASTIC MESHLESS GALERKIN METHOD AND ITS APPLICATION IN ANALYSIS OF EXTRUSION PROCESSES

Under the hypothesis of the rigid-plastic material, specific efforts are placed on the developments of the key simulation techniques of the meshless Galerkin method because of the complexity of the deformation process as well as the generality and atomization of the simulation procedures for non-steady state large deformation plastic processes, therefore, an adaptive rigid meshless Galerkin method is developed. The influence domain control method is used in the least square approximation by dynamic evaluation of the magnitude of the influence domain and the effective control of the amount and the positions of the points in the least square approximation in order to improve approximation precision. The amount of the Gauss integration points in the discrete domain is maintained in a considerable magnitude in order to ensure the integration precision in the discrete domain. The length of the frictional boundary of the plastic deformation process may be getting longer when its deforma- tion is getting severe. Thus, the densities of the boundary points of some places get lower. The adaptive boundary points setting method is employed to improve the approximation precision of the boundary points and enhance the constraint of the boundary condition by adaptive control of boundary point density. Some typical extrusion processes are analyzed, detail simulation results such as the deformation field, velocity field, effective strain field, effective strain rate field, the volume loss curve and load-stroke curve are obtained. The effectiveness of the method developed is demonstrated and the precision of the meshless simulation is proved by overall comparison with the results obtained by using the commercial software deform.

RADIAL EXTRUSION PROCESS BY THREE-DIMENSIONAL RIGID-PLASTIC FEM SIMULATION

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RIGID-PLASTIC/RIGID-VISCOPLASTIC FEM BASED ON LINEAR PROGRAMMING-THEORETICAL MODELING AND APPLICATION FOR PLANE-STRAIN PROBLEMS

A new rigid-plastic/rigid-viscoplastic (RP/RVP) FEM based on linearprogramming (LP) for plane-strain metal forming simulation is proposed. Compared with thetraditional RP/RVP FEM based on iteration solution, it has some remarkable advantages, such a it'sfree of convergence problem and its convenience in contact, incompressibility constraint and rigidzone treatment. Two solution examples are provided to validate its accuracy and efficiency.

Study on Remeshing Technique for Three-Dimensional Rigid-plastic Finite Element Simulation

A new method of three-dimensional remeshing is proposed for rigid-plastic finiteelement analysis of a complicated forging process.The forging process of a cylindricalhousing has been simulated to show the effectiveness of the scheme.The result ofsimulation shows that the computation can be effectively carried out by using the des-cribed remeshing scheme.

ANALYSIS OF THE LARGE DEFLECTION DYNAMIC RESPONSE OF RIGID-PLASTIC CIRCULAR PLATE RESTING ON FLUID

A study is presented for the large deflection dynamic response of rigid- plastic circular plate resting on potential fluid under a rectangular pressure pulse load. By virtue of Hankel integral transform technique,this interaction problem is reduced to a problem of dynamic plastic response of the plate in vacuum.The closed-form solutions are derived for both middle and high pressure loads by solving the equations of motion with the large deflection in the range where both bending moments and membrane forces are important.Some numerical results are given.

Neural stem cells promote neuroplasticity: a promising therapeutic strategy for the treatment of Alzheimer’s disease

Recent studies have demonstrated that neuroplasticity,such as synaptic plasticity and neurogenesis,exists throughout the normal lifespan but declines with age and is significantly impaired in individuals with Alzheimer’s disease.Hence,promoting neuroplasticity may represent an effective strategy with which Alzheimer’s disease can be alleviated.Due to their significant ability to self-renew,differentiate,and migrate,neural stem cells play an essential role in reversing synaptic and neuronal damage,reducing the pathology of Alzheimer’s disease,including amyloid-β,tau protein,and neuroinflammation,and secreting neurotrophic factors and growth factors that are related to plasticity.These events can promote synaptic plasticity and neurogenesis to repair the microenvironment of the mammalian brain.Consequently,neural stem cells are considered to represent a potential regenerative therapy with which to improve Alzheimer’s disease and other neurodegenerative diseases.In this review,we discuss how neural stem cells regulate neuroplasticity and optimize their effects to enhance their potential for treating Alzheimer’s disease in the clinic.

Upcycling plastic wastes into value-added products via electrocatalysis and photoelectrocatalysis

Plastic,renowned for its versatility,durability,and cost-effectiveness,is indispensable in modern society.Nevertheless,the annual production of nearly 400 million tons of plastic,coupled with a recycling rate of only 9%,has led to a monumental environmental crisis.Plastic recycling has emerged as a vital response to this crisis,offering sustainable solutions to mitigate its environmental impact.Among these recycling efforts,plastic upcycling has garnered attention,which elevates discarded plastics into higher-value products.Here,electrocatalytic and photoelectrocatalytic treatments stand at the forefront of advanced plastic upcycling.Electrocatalytic or photoelectrocatalytic treatments involve chemical reactions that facilitate electron transfer through the electrode/electrolyte interface,driven by electrical or solar energy,respectively.These methods enable precise control of chemical reactions,harnessing potential,current density,or light to yield valuable chemical products.This review explores recent progress in plastic upcycling through electrocatalytic and photoelectrocatalytic pathways,offering promising solutions to the plastic waste crisis and advancing sustainability in the plastics industry.

Lymphatic plastic bronchitis and primary chylothorax: A study based on computed tomography lymphangiography

BACKGROUND This study presents an evaluation of the computed tomography lymphangio-graphy(CTL)features of lymphatic plastic bronchitis(PB)and primary chylotho-rax to improve the diagnostic accuracy for these two diseases.AIM To improve the diagnosis of lymphatic PB or primary chylothorax,a retrospective analysis of the clinical features and CTL characteristics of 71 patients diagnosed with lymphatic PB or primary chylothorax was performed.METHODS The clinical and CTL data of 71 patients(20 with lymphatic PB,41 with primary chylothorax,and 10 with lymphatic PB with primary chylothorax)were collected retrospectively.CTL was performed in all patients.The clinical manifestations,CTL findings,and conventional chest CT findings of the three groups of patients were compared.The chi-square test or Fisher's exact test was used to compare the differences among the three groups.A difference was considered to be statistically significant when P<0.05.RESULTS(1)The percentages of abnormal contrast medium deposits on CTL in the three groups were as follows:Thoracic duct outlet in 14(70.0%),33(80.5%)and 8(80.0%)patients;peritracheal region in 18(90.0%),15(36.6%)and 8(80.0%)patients;pleura in 6(30.0%),33(80.5%)and 9(90.0%)patients;pericardium in 6(30.0%),6(14.6%)and 4(40.0%)patients;and hilum in 16(80.0%),11(26.8%)and 7(70.0%)patients;and(2)the abnormalities on conven-tional chest CT in the three groups were as follows:Ground-glass opacity in 19(95.0%),18(43.9%)and 8(80.0%)patients;atelectasis in 4(20.0%),26(63.4%)and 7(70.0%)patients;interlobular septal thickening in 12(60.0%),11(26.8%)and 3(30.0%)patients;bronchovascular bundle thickening in 14(70.0%),6(14.6%)and 4(40.0%)patients;localized mediastinal changes in 14(70.0%),14(34.1%),and 7(70.0%)patients;diffuse mediastinal changes in 6(30.0%),5(12.2%),and 3(30.0%)patients;cystic lesions in the axilla in 2(10.0%),6(14.6%),and 2(20.0%)patients;and cystic lesions in the chest wall in 0(0%),2(4.9%),and 2(4.9%)patients.CONCLUSION CTL is well suited to clarify the characteristics of lymphatic PB and primary chylothorax.This method is an excellent tool for diagnosing these two diseases.

3'-Deoxyadenosin alleviates methamphetamine-induced aberrant synaptic plasticity and seeking behavior by inhibiting the NLRP3 inflammasome

Methamphetamine addiction is a brain disorder characterized by persistent drug-seeking behavior, which has been linked with aberrant synaptic plasticity. An increasing body of evidence suggests that aberrant synaptic plasticity is associated with the activation of the NOD-like receptor family pyrin domain containing-3(NLRP3) inflammasome. 3′-Deoxyadenosin, an active component of the Chinese fungus Cordyceps militaris, has strong anti-inflammatory effects. However, whether 3′-deoxyadenosin attenuates methamphetamine-induced aberrant synaptic plasticity via an NLRP3-mediated inflammatory mechanism remains unclear. We first observed that 3′-deoxyadenosin attenuated conditioned place preference scores in methamphetamine-treated mice and decreased the expression of c-fos in hippocampal neurons. Furthermore, we found that 3′-deoxyadenosin reduced the aberrant potentiation of glutamatergic transmission and restored the methamphetamine-induced impairment of synaptic plasticity. We also found that 3′-deoxyadenosin decreased the expression of NLRP3 and neuronal injury. Importantly, a direct NLRP3 deficiency reduced methamphetamine-induced seeking behavior, attenuated the impaired synaptic plasticity, and prevented neuronal damage. Finally, NLRP3 activation reversed the effect of 3′-deoxyadenosin on behavior and synaptic plasticity, suggesting that the anti-neuroinflammatory mechanism of 3′-deoxyadenosin on aberrant synaptic plasticity reduces methamphetamine-induced seeking behavior. Taken together, 3′-deoxyadenosin alleviates methamphetamine-induced aberrant synaptic plasticity and seeking behavior by inhibiting the NLRP3 inflammasome.

The Future of Plasticizers: Biobased and Oligomeric

The deficiencies of popular phthalate plasticizers(ready migration from a polymer matrix into which they have been incorporated,flammability,environmental pollution,human health risks)have stimulated efforts to develop new effective,nonmigrating,low-cost,nontoxic replacements.In the main,these have been based on readilyavailable,nontoxic biobased precursors.Some,including those prepared from plant oils,have been generated from biomaterials themselves.However,the more numerous and generally more effective have been generated from discrete compounds produced from various biomaterials.Several structural features of effective plasticizers have been recognized.Polar functionality is required to assure compatibility with a wide range of polymeric materials,including poly(vinyl chloride)(PVC),the most heavily plasticized polymer.A branched structure greatly enhances the effectiveness of compounds used as plasticizers.An oligomeric structure may strongly limit or prevent migration from a polymer matrix.Hyperbranched oligomers of defined structure derived from the readilyavailable,inexpensive,nontoxic biomonomers,glycerol and adipic acid contain all these features and are excellent plasticizers.They contain ester functionality,are highly branched,and display a large number of end groups,all of which contribute to their effectiveness as plasticizers.

Recent Advance in Synaptic Plasticity Modulation Techniques for Neuromorphic Applications

Manipulating the expression of synaptic plasticity of neuromorphic devices provides fascinating opportunities to develop hardware platforms for artifi-cial intelligence.However,great efforts have been devoted to exploring biomimetic mechanisms of plasticity simulation in the last few years.Recent progress in various plasticity modulation techniques has pushed the research of synaptic electronics from static plasticity simulation to dynamic plasticity modulation,improving the accuracy of neuromorphic computing and providing strategies for implementing neuromorphic sensing functions.Herein,several fascinating strategies for synap-tic plasticity modulation through chemical techniques,device structure design,and physical signal sensing are reviewed.For chemical techniques,the underly-ing mechanisms for the modification of functional materials were clarified and its effect on the expression of synaptic plasticity was also highlighted.Based on device structure design,the reconfigurable operation of neuromorphic devices was well demonstrated to achieve programmable neuromorphic functions.Besides,integrating the sensory units with neuromorphic processing circuits paved a new way to achieve human-like intelligent perception under the modulation of physical signals such as light,strain,and temperature.Finally,considering that the relevant technology is still in the basic exploration stage,some prospects or development suggestions are put forward to promote the development of neuromorphic devices.