Neural stem cell-derived exosome as a nano-sized carrier for BDNF delivery to a rat model of ischemic stroke

Our previo us study demonstrated the potential therapeutic role of human neural stem cell-derived exosomes(hNSC-Exo)in ischemic stroke.Here,we loaded brain-derived neurotrophic factor(BDNF)into exosomes derived from NSCs to construct engineered exosomes(BDNF-hNSC-Exo)and compared their effects with those of hNSC-Exo on ischemic stroke both in vitro and in vivo.In a model of H_(2)O_(2)-induced oxidative stress in NSCs,BDNF-hNSC-Exo markedly enhanced cell survival.In a rat middle cerebral arte ry occlusion model,BDNF-hNSC-Exo not only inhibited the activation of microglia,but also promoted the differentiation of endogenous NSCs into neurons.These results suggest that BDNF can improve the function of NSC-derived exosomes in the treatment of ischemic stro ke.Our research may support the clinical use of other neurotrophic factors for central nervous system diseases.

Neural stem cell transplantation therapy for brain ischemic stroke:Review and perspectives

Brain ischemic stroke is one of the most common causes of death and disability,currently has no efficient therapeutic strategy in clinic.Due to irreversible functional neurons loss and neural tissue injury,stem cell transplantation may be the most promising treatment approach.Neural stem cells(NSCs)as the special type of stem cells only exist in the nervous system,can differentiate into neurons,astrocytes,and oligodendrocytes,and have the abilities to compensate insufficient endogenous nerve cells and improve the inflammatory microenvironment of cell survival.In this review,we focused on the important role of NSCs therapy for brain ischemic stroke,mainly introduced the methods of optimizing the therapeutic efficacy of NSC transplantation,such as transfection and overexpression of specific genes,pretreatment of NSCs with inflammatory factors,and co-transplantation with cytokines.Next,we discussed the potential problems of NSC transplantation which seriously limited their rapid clinical transformation and application.Finally,we expected a new research topic in the field of stem cell research.Based on the bystander effect,exosomes derived from NSCs can overcome many of the risks and difficulties associated with cell therapy.Thus,as natural seed resource of nervous system,NSCs-based cell-free treatment is a newly therapy strategy,will play more important role in treating ischemic stroke in the future.

Quantum twisted double-slits experiments:confirming wavefunctions'physical reality

Are quantum states real? This most fundamental question in quantum mechanics has not yet been satisfactorily resolved, although its realistic interpretation seems to have been rejected by various delayedchoice experiments. Here, to address this long-standing issue, we present a quantum twisted double-slit experiment. By exploiting the subluminal feature of twisted photons, the real nature of a photon during its time in flight is revealed for the first time. We found that photons' arrival times were inconsistent with the states obtained in measurements but agreed with the states during propagation. Our results demonstrate that wavefunctions describe the realistic existence and evolution of quantum entities rather than a pure mathematical abstraction providing a probability list of measurement outcomes. This finding clarifies the long-held misunderstanding of the role of wavefunctions and their collapse in the evolution of quantum entities.

Beyond the operator algebra—To be nonlocal realism of quantum mechanics

In 1905,Albert Einstein presented his milestone theory of photons in his paper titled "On a Heuristic Viewpoint Concerning the Production and Transformation of Light"based on Max Planck’s black-body radiation theory.The groundbreaking theory successfully solved the paradox between Maxwell’s wave theory of light and the experimental