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1.
Biomaterials ; 309: 122622, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38797119

RESUMO

Nondestructive penetration of the blood-brain barrier (BBB) to specifically prevent iron deposition and the generation of reactive oxygen species (ROS) shows great potential for treating Parkinson's disease (PD). However, effective agents with distinct mechanisms of action remain scarce. Herein, a N-doping carbon dot (CD) emitting red light was prepared, which can sacrifice ROS and produce nitric oxide (NO) owing to its surface N-involved groups conjugated to the sp2-hybrided π-system. Meanwhile, CD can chelate iron ions, thus depressing the catalytic Fe cycle and *OH detaching to inhibit the Fenton reaction. By modifying lactoferrin (Lf) via polyethylene glycol (PEG), the resulting CD-PEG-Lf (CPL) can nondestructively cross the BBB, targeting the dopaminergic neurons via both NO-mediated reversible BBB opening and Lf receptor-mediated transportation. Accordingly, it can serve as an antioxidant, reducing oxidative stress via its unique iron chelation, free radical sacrificing, and synergy with iron reflux prevention originating from Lf. Thus, it can significantly reduce brain inflammation and improve the behavioral performance of PD mice. Additionally, CPL can image the PD via its red fluorescence. Finally, this platform can be metabolized out of the brain through cerebrospinal fluid circulation without causing obvious side effects, promising a robust treatment for PD.


Assuntos
Antioxidantes , Barreira Hematoencefálica , Carbono , Ferro , Óxido Nítrico , Doença de Parkinson , Animais , Óxido Nítrico/metabolismo , Doença de Parkinson/metabolismo , Doença de Parkinson/tratamento farmacológico , Carbono/química , Ferro/metabolismo , Ferro/química , Antioxidantes/química , Antioxidantes/metabolismo , Camundongos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Masculino , Lactoferrina/química , Lactoferrina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Polietilenoglicóis/química , Pontos Quânticos/química , Estresse Oxidativo/efeitos dos fármacos , Nanopartículas/química , Íons , Humanos , Camundongos Endogâmicos C57BL
2.
Biomater Sci ; 11(21): 6942-6976, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37750827

RESUMO

Covalent organic frameworks (COFs) are composed of small organic molecules linked via covalent bonds, which have tunable mesoporous structure, good biocompatibility and functional diversities. These excellent properties make COFs a promising candidate for constructing biomedical nanoplatforms and provide ample opportunities for nanomedicine development. A systematic review of the linkage types and synthesis methods of COFs is of indispensable value for their biomedical applications. In this review, we first summarize the types of various linkages of COFs and their corresponding properties. Then, we highlight the reaction temperature, solvent and reaction time required by different synthesis methods and show the most suitable synthesis method by comparing the merits and demerits of various methods. To appreciate the cutting-edge research on COFs in bioscience technology, we also summarize the bio-related applications of COFs, including drug delivery, tumor therapy, bioimaging, biosensing and antimicrobial applications. We hope to provide insight into the interdisciplinary research on COFs and promote the development of COF nanomaterials for biomedical applications and their future clinical translations.

3.
Med Sci Monit ; 27: e933454, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34958655

RESUMO

BACKGROUND We aimed to evaluate the efficacy and safety of pneumatic trabeculoplasty (PNT) and selective laser trabeculoplasty (SLT) in the treatment of primary open-angle glaucoma (POAG) and ocular hypertension (OHT). MATERIAL AND METHODS We randomly divided 120 cases (120 eyes) of POAG or OHT into 2 groups: PNT and SLT. The changes in anterior chamber angle, intraocular pressure (IOP), treatment effect, macular retinal ganglion cell complex (GCC) thickness, visual field, adverse reactions, and complications were observed before and 3 months after treatment. RESULTS In the PNT group, the opening range of anterior chamber angle at 1 week, 2 weeks, 1 month, and 3 months after surgery was significantly larger than that before surgery. In the SLT group, the open range of anterior chamber angle was significantly less than that before surgery at 1 week and 2 weeks after surgery. The open range of anterior chamber angle in the PNT group was significantly larger than that in the SLT group at 1 week, 2 weeks, 1 month, and 3 months after surgery. The mean IOP of the 2 groups decreased significantly after surgery. The postoperative mean IOP of the SLT group was significantly higher than that of the PNT group, and the decrease of IOP in the PNT group was significantly greater than that of the SLT group. The effective rate of the PNT group was higher than that of the SLT group. CONCLUSIONS Both PNT and SLT can reduce the IOP of patients with POAG and OHT. PNT appears to have better short-term treatment efficiency than SLT.


Assuntos
Glaucoma de Ângulo Aberto/cirurgia , Hipertensão Ocular/cirurgia , Trabeculectomia/métodos , Adulto , Idoso , Feminino , Humanos , Terapia a Laser/métodos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
4.
Sci Total Environ ; 626: 366-376, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29353782

RESUMO

Ground ice is a distinctive feature of permafrost terrain. The vertical distribution and factors controlling the hydrochemistry of ground ice are important for studying soil moisture and salt migration during the freeze-thaw process in soil. These factors are also important components of hydrological cycles in cold regions. The hydrochemical characteristics of ground ice on the Qinghai-Tibetan Plateau (QTP) are not well known. We examined the characteristics of ground ice hydrochemistry using data from 9 soil profiles in permafrost regions of the central QTP. The isotopes and anion concentrations of subsurface water on the QTP were higher than those in Arctic polygonal ground regions. The spatial distribution of anions was complex. Well-developed hydrochemical depth gradients occurred within the soil profile. Isotopes decreased and anions increased with depth, suggesting general vertical patterns of soil hydrochemistry across different permafrost regions. Cl- and SO42- concentrations in soil water increased with depth, while NO3- concentration did not change with depth. Freeze-out fractionation, self-purification, and desalination greatly impact soil hydrochemistry. The major factors controlling variation of soil water chemistry were soil moisture, air temperature, and active layer thickness. The results could provide a framework for understanding ground ice origins and the moisture and salt migration pathways in the context of permafrost changes. This information could be useful in developing process-based permafrost hydrologic models.

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