α-Synuclein pathology from the body to the brain:so many seeds so close to the central soil

α-Synuclein is a protein that mainly exists in the presynaptic terminals.Abnormal folding and accumulation of α-synuclein are found in several neurodegenerative diseases,including Parkinson’s disease.Aggregated and highly phospho rylated a-synuclein constitutes the main component of Lewy bodies in the brain,the pathological hallmark of Parkinson s disease.For decades,much attention has been focused on the accumulation of α-synuclein in the brain parenchyma rather than considering Parkinson s disease as a systemic disease.Recent evidence demonstrates that,at least in some patients,the initial α-synuclein pathology originates in the peripheral organs and spreads to the brain.Injection of α-synuclein preformed fibrils into the gastrointestinal tra ct trigge rs the gutto-brain propagation of α-synuclein pathology.However,whether α-synuclein pathology can occur spontaneously in peripheral organs independent of exogenous α-synuclein preformed fibrils or pathological α-synuclein leakage from the central nervous system remains under investigation.In this review,we aimed to summarize the role of peripheral α-synuclein pathology in the pathogenesis of Parkinson’s disease.We also discuss the pathways by which α-synuclein pathology spreads from the body to the brain.

In Situ Electrochemical Mn(Ⅲ)/Mn(Ⅳ) Generation of Mn(Ⅱ)O Electrocatalysts for High-Performance Oxygen Reduction

Among various earth-abundant and noble metal-free catalysts for oxygen reduction reaction(ORR),manganese-based oxides are promising candidates owing to the rich variety of manganese valence.Herein,an extremely facile method for the synthesis of cubic and orthorhombic phase coexisting Mn(Ⅱ)O electrocatalyst as an efficient ORR catalyst was explored.The obtained MnO electrocatalyst with oxygen vacancies shows a significantly elevated ORR catalytic activity with a half-wave potential(E1/2) of as high as 0.895 V,in comparison with that of commercial Pt/C(E1/2=0.877 V).More impressively,the MnO electrocatalyst exhibits a marked activity enhancement after test under a constant applied potential for 1000 s thanks to the in situ generation and stable presence of high-valence manganese species(Mn^3+ and Mn^4+) during the electrochemical process,initiating a synergetic catalytic effect with oxygen vacancies,which is proved to largely accelerate the adsorption and reduction of O_2 molecules favoring the ORR activity elevation.Such an excellent ORR catalytic performance of this MnO electrocatalyst is applied in Zn-air battery,which shows an extra-high peak power density of 63.2 mW cm^-2 in comparison with that(47.4 m W cm^-2) of commercial Pt/C under identical test conditions.

Photocatalytic in situ H_(2)O_(2) production and activation for enhanced ciprofloxacin degradation over CeO_(2)-Co_(3)O_(4)/g-C_(3)N_(4):key role of CeO_(2)

The abused ciprofloxacin antibiotics have caused significant environmental damage.Although oxidative degradation of ciprofloxacin exhibits promising efficacy,it often entails excessive energy consumption.Hence,it is necessary to explore an effective and ecologically sustainable degradation strategy.Herein,we demonstrated that g-C_(3)N_(4) decorated with the coordinated CeO_(2)and Co_(3)O_(4)(CeO_(2)-Co_(3)O_(4)/CN)exhibited effective ciprofloxacin photodegradation via in situ H_(2)O_(2) production and activation mechanism.Results indicate that the introduced CeO_(2) enhances the transference of photogenerated electrons to O_(2) by adjusting the oxygen vacancy of photocatalyst,thereby increasing the generation of superoxide radicals,which in turn generate H_(2)O_(2),resulting in a 22.4-fold increase in H_(2)O_(2) generation over g-C_(3)N_(4).Moreover,the in situ H_(2)O_(2)generation facilitated by CeO_(2) is confirmed to be essential for ciprofloxacin degradation via CeO_(2)-Co_(3)O_(4)/CN,as it provides enough oxidant for Co_(3)O_(4) to activate into hydroxyl radicals for the pollutants degradation.Ultimately,CeO_(2)-Co_(3)O_(4)/CN achieves a ciprofloxacin degradation ratio of 97.7%within 80 min.This study introduces a novel approach that combines H_(2)O_(2) generation and activation,offering an innovative perspective for achieving clean and efficient purification of antibiotic-contaminated water.

Modification of tamarind fruit shell powder with in situ generated copper nanoparticles by single step hydrothermal method

Tamarind fruit shell powder(TFSP)with particle size of<50μm(obtained from cleaned tamarind fruit shells)was modified with in situ generated copper nanoparticles(CuNPs)by simple one step hydrothermal method.The modified TFSP was characterized by scanning electron microscope(SEM),Fourier transform infrared(FT-IR)spectroscopy,X-ray diffraction(XRD),thermogravi-metric analysis(TGA)and antibacterial tests.The generated stable CuNPs on the surface of the modified TFSP were spherical in shape with an average size of 88 nm.The FT-IR spectroscopy analysis indicated the involvement of the functional groups of the TFSP in the generation and stabilization of the CuNPs.The XRD analysis indicated the presence of both CuNPs and Cu 2 O nanoparticles in the modified TFSP.The thermal analysis indicated the presence of 5.6 wt%of copper nanoparticles as calculated from the difference of residual char content between the un-modified and modified TFSP.The modified TFSP with in situ generated CuNPs exhibited obvious antibacterial activity against both the Gram negative and Gram positive bacteria and hence can be considered as low cost filler in the preparation of antibacterial polymer hybrid nanocomposites for packaging and medical applications.

Nanocomposite egg shell powder with in situ generated silver nanoparticles using inherent collagen as reducing agent

Silver nanoparticles(AgNPs)were in situ generated in poultry hen egg shell powder(ESP)by one step thermal assisted method using the inherently present collagen as a reducing agent.The nanocomposite egg shell powder(NCESP)with in situ generated silver nanoparticles was charac-terized by scanning electron microscopy(SEM),Fourier transform infrared(FT-IR)spectroscopy,X-ray diffraction(XRD),thermogravimetric analysis(TGA)and antibacterial tests.The prepared NCESP had the spherical AgNPs in the size range of 50-120 nm with most of them from 81 nm to 90 nm.Further,the average size of the AgNPs generated in the NCESP was 88 nm.The X-ray analysis indicated the presence of both AgNPs and AgO nanoparticles(AgONPs)in the NCESP.The possible mechanism of generation of AgNPs and AgONPs in the NCESP was also proposed.The thermal stability of the NCESP was found to be higher than that of the ESP.The NCESP ex-hibited excellent antibacterial activity against both the Gram negative and positive bacteria.The NCESP made from poultry waste ESP can be utilized as a low-cost antibacterial cleaning powder for house ware and also as low-cost antibacterial filler in polymer matrices to make antibacterial hybrid nanocomposites.

Preparation and properties of cellulose nanocomposite fabrics with in situ generated silver nanoparticles by bioreduction method

The aim of the present study was to develop antibacterial cellulose(cotton)nanocomposite fab-rics(CNCFs)with in situ generated silver nanoparticles using medicinal plant Vitex leaf extract.The developed CNCFs were characterized by scanning electron microscope(SEM),Fourier transform infrared(FT-IR)spectroscopy,X-ray diffraction(XRD)and antibacterial tests.Further,these CNCFs possessed good antibacterial activities.These CNCFs prepared using simple and environmentally friendly method can be considered for medical applications in,such as,surgical aprons,wound cleaning,wound dressing,and hospital bed materials.