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1.
Front Neurol ; 15: 1413582, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974685

RESUMEN

Background: Epilepsy ranks among the most common neurological disorders worldwide, frequently accompanied by depression as a prominent comorbidity. This study employs bibliometric analysis to reveal the research of comorbid epilepsy and depression over the past two decades, aiming to explore trends and contribute insights to ongoing investigations. Methods: We conducted a comprehensive search on the Web of Science Core Collection database and downloaded relevant publications on comorbid epilepsy and depression published from 2003 to 2023. VOSviewer and CiteSpace were mainly used to analyze the authors, institutions, countries, publishing journals, reference co-citation patterns, keyword co-occurrence, keyword clustering, and other aspects to construct a knowledge atlas. Results: A total of 5,586 publications related to comorbid epilepsy and depression were retrieved, with a general upward trend despite slight fluctuations in annual publications. Publications originated from 121 countries and 636 institutions, with a predominant focus on clinical research. The United States led in productivity (1,529 articles), while Melbourne University emerged as the most productive institution (135 articles). EPILEPSY & BEHAVIOR was the journal with the highest publication output (1,189 articles) and citation count. Keyword analysis highlighted emerging trends, including "recognitive impairment" and "mental health," indicating potential future research hotspots and trends. Conclusion: This study is one of the first to perform a bibliometric analysis of the 20-year scientific output of comorbid epilepsy and depression. While research has trended upwards, ambiguity in pathogenesis and the absence of standardized diagnostic guidelines remain concerning. Our analysis offers valuable guidance for researchers, informing that this might be a strong area for future collaborations.

2.
Artículo en Inglés | MEDLINE | ID: mdl-39031069

RESUMEN

High-efficiency Pb-Sn narrow-bandgap perovskite solar cells (PSCs) heavily rely on PEDOT:PSS as the hole-transport layer (HTL) owing to its excellent electrical conductivity, dopant-free nature, and facile solution processability. However, the shallow work function (WF) of PEDOT:PSS consequently results in severe minority carrier recombination at the perovskite/HTL interface. Here, we tackle this issue by an in situ interface engineering strategy using a new molecule called 2-fluoro benzylammonium iodide (FBI) that suppresses nonradiative recombination near the Pb-Sn perovskite (FA0.6MA0.4Pb0.4Sn0.6I3)/HTL bottom interface. The WF of PEDOT:PSS increases by 0.1 eV with FBI modification, resulting in Pb-Sn PSCs with 20.5% efficiency and an impressive VOC of 0.843 V. Finally, we have successfully transferred our in situ buried interface modification strategy to fabricate blade-coated FA0.6MA0.4Pb0.4Sn0.6I3 PSCs with 18.3% efficiency and an exceptionally high VOC of 0.845 V.

3.
J Am Chem Soc ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38838168

RESUMEN

Molecular self-assembly is a widely recognized approach for fabricating biomimetic functional nanostructures. Here, we report the synthesis of two giant hollow coronoid-like supramolecular hexagons, H1 and H2. These hexagons feature large cavities, showcasing unique inner and outer hexagons fixed by specific connectivities for enhanced stability and high metal center density. H1 exhibits properties that can be transformed through the thermodynamic conversion of the metallopolymer formed by L1 and L2. With an edge length of 6.8 nm, H2 is one of the largest hexagons reported to date. 1D and 2D NMR, TEM, ESI-MS, and TWIM-MS experiments provided conclusive evidence for the composition and structure of the assembled hexagons. This work demonstrates the feasibility of constructing giant supramolecular architectures with precise control over their size and shape, opening up new possibilities for the design and synthesis of sophisticated supramolecules and nonbiological materials.

4.
Front Bioeng Biotechnol ; 12: 1403511, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38919382

RESUMEN

Gliomas are typical malignant brain tumours affecting a wide population worldwide. Operation, as the common treatment for gliomas, is always accompanied by postoperative drug chemotherapy, but cannot cure patients. The main challenges are chemotherapeutic drugs have low blood-brain barrier passage rate and a lot of serious adverse effects, meanwhile, they have difficulty targeting glioma issues. Nowadays, the emergence of nanoparticles (NPs) drug delivery systems (NDDS) has provided a new promising approach for the treatment of gliomas owing to their excellent biodegradability, high stability, good biocompatibility, low toxicity, and minimal adverse effects. Herein, we reviewed the types and delivery mechanisms of NPs currently used in gliomas, including passive and active brain targeting drug delivery. In particular, we primarily focused on various hopeful types of NPs (such as liposome, chitosan, ferritin, graphene oxide, silica nanoparticle, nanogel, neutrophil, and adeno-associated virus), and discussed their advantages, disadvantages, and progress in preclinical trials. Moreover, we outlined the clinical trials of NPs applied in gliomas. According to this review, we provide an outlook of the prospects of NDDS for treating gliomas and summarise some methods that can enhance the targeting specificity and safety of NPs, like surface modification and conjugating ligands and peptides. Although there are still some limitations of these NPs, NDDS will offer the potential for curing glioma patients.

5.
Adv Mater ; 36(28): e2401359, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38663867

RESUMEN

With the continuous upsurge in demand for wearable energy, nanogenerators are increasingly required to operate under extreme environmental conditions. Even though they are at the cutting edge of technology, nanogenerators have difficulty producing high-quality electrical output at very extreme temperatures. Here, a triboelectric basalt textile (TBT) with an ultrawide operational temperature range (from -196 to 520 °C) is created employing basalt material as the main body. The output power density of the TBT, in contrast to most conventional nanogenerators, would counterintuitively rise by 2.3 times to 740.6 mW m-2 after heating to 100 °C because the high temperature will enhance the material's interface polarization and electronic kinetic energy. The TBT retains ≈55% of its initial electrical output even after heating in the flame of an alcohol lamp (520 °C). Surprisingly, the TBTs output voltage may retain over 85% of its initial value even after submerging in liquid nitrogen. The TBTs exceptional resistance to heat and cold indicates its possible use in high and low latitudes, high altitudes, deserts, and even space settings.

6.
Sci Adv ; 10(16): eadl2063, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38640232

RESUMEN

All-perovskite tandem solar cells (TSCs) have exhibited higher efficiencies than single-junction perovskite solar cells (PSCs) but still suffer from the unsatisfactory performance of low-bandgap (LBG) tin-lead (Sn-Pb) subcells. The inherent properties of PEDOT:PSS are crucial to high-performance Sn-Pb perovskite films and devices; however, the underlying mechanism has not been fully explored and revealed. Here, we report a facile oxalic acid treatment of PEDOT:PSS (OA-PEDOT:PSS) to precisely regulate its work function and surface morphology. OA-PEDOT:PSS shows a larger work function and an ordered reorientation and fiber-shaped film morphology with efficient hole transport pathways, leading to the formation of more ideal hole-selective contact with Sn-Pb perovskite for suppressing interfacial nonradiative recombination losses. Moreover, OA-PEDOT:PSS induces (100) preferred orientation growth of perovskite for higher-quality Sn-Pb films. Last, the OA-PEDOT:PSS-tailored LBG PSC yields an impressive efficiency of up to 22.56% (certified 21.88%), enabling 27.81% efficient all-perovskite TSC with enhanced operational stability.

7.
Bioengineering (Basel) ; 11(3)2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38534567

RESUMEN

The 12-lead electrocardiogram (ECG) is crucial in assessing patient decisions. However, portable ECG devices capable of acquiring a complete 12-lead ECG are scarce. For the first time, a deep learning-based method is proposed to reconstruct the 12-lead ECG from Frank leads (VX, VY, and VZ) or EASI leads (VES, VAS, and VAI). The innovative ECG reconstruction network called M2Eformer is composed of a 2D-ECGblock and a ProbDecoder module. The 2D-ECGblock module adaptively segments EASI leads into multi-periods based on frequency energy, transforming the 1D time series into a 2D tensor representing within-cycle and between-cycle variations. The ProbDecoder module aims to extract Probsparse self-attention and achieve one-step output for the target leads. Experimental results from comparing recorded and reconstructed 12-lead ECG using Frank leads indicate that M2Eformer outperforms traditional ECG reconstruction methods on a public database. In this study, a self-constructed database (10 healthy individuals + 15 patients) was utilized for the clinical diagnostic validation of ECG reconstructed from EASI leads. Subsequently, both the ECG reconstructed using EASI and the recorded 12-lead ECG were subjected to a double-blind diagnostic experiment conducted by three cardiologists. The overall diagnostic consensus among three cardiology experts, reaching a rate of 96%, indicates the significant utility of EASI-reconstructed 12-lead ECG in facilitating the diagnosis of cardiac conditions.

8.
Nat Energy ; 9(2): 172-183, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38419691

RESUMEN

The stabilization of grain boundaries and surfaces of the perovskite layer is critical to extend the durability of perovskite solar cells. Here we introduced a sulfonium-based molecule, dimethylphenethylsulfonium iodide (DMPESI), for the post-deposition treatment of formamidinium lead iodide perovskite films. The treated films show improved stability upon light soaking and remains in the black α phase after two years ageing under ambient condition without encapsulation. The DMPESI-treated perovskite solar cells show less than 1% performance loss after more than 4,500 h at maximum power point tracking, yielding a theoretical T80 of over nine years under continuous 1-sun illumination. The solar cells also display less than 5% power conversion efficiency drops under various ageing conditions, including 100 thermal cycles between 25 °C and 85 °C and an 1,050-h damp heat test.

9.
BMC Pregnancy Childbirth ; 23(1): 840, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38057742

RESUMEN

BACKGROUND: Prior studies have shown that, when administered as an intravenous bolus to prevent uterine atony, prophylactic phenylephrine infusion increased the dose requirement of oxytocin and second-line uterotonics. For the prevention of uterine atony, oxytocin should be delivered by continuous infusion. Here, we aimed to determine the ED50 and ED90 parameters (the effective doses for 50 and 90% patients without uterine atony) of oxytocin for co-infusion with prophylactic phenylephrine during cesarean delivery. METHODS: In this prospective randomized double-blinded dose-finding study, one hundred patients were divided into four groups to receive 2.5, 5.0, 7.5, or 10 IU/h oxytocin infusion, after the umbilical cord was clamped during the study period. The uterine tone was evaluated and defined as either adequate or inadequate. Probit regression analysis was applied to calculate the ED50 and ED90 of oxytocin infusion. Uterine tone, the percentage of patients who needed additional oxytocin bolus, second-line uterotonics, side effects, estimated blood loss, and neonatal outcomes were monitored. RESULTS: The estimated ED50 and ED90 values of the oxytocin infusion doses for the prevention of uterine atony were 1.9 IU/h (95% CI -4.6-3.8) IU/h and 9.3 IU/h (95% CI 7.3-16.2) IU/h, respectively. Across groups, there was a significant linear trend between the infusion dose and the percentage of patients who required additional oxytocin (p-value = 0.002). No differences were observed in the incidence of side effects and neonatal outcomes. CONCLUSION: Under the conditions of this study, the ED90 of oxytocin infusion for the prevention of uterine atony was 9.3 IU/h, which is higher than the current recommendation. This finding is helpful for clinical practice, because of the routine use of phenylephrine in cesarean delivery. Further studies are needed to determine the appropriate initial bolus of oxytocin after neonatal delivery. TRIAL REGISTRATION: The study was registered on the Chinese Clinical Trial Register (register no. ChiCTR2200059556 ).


Asunto(s)
Hipotensión , Oxitócicos , Inercia Uterina , Embarazo , Femenino , Recién Nacido , Humanos , Oxitocina , Fenilefrina , Estudios Prospectivos , Hipotensión/etiología , Hipotensión/prevención & control , Método Doble Ciego , Infusiones Intravenosas
10.
Inorg Chem ; 62(23): 8923-8930, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37246851

RESUMEN

As a result of their optical and redox properties, bipyridyl (bpy) and terpyridyl (tpy) ruthenium complexes play vital roles in numerous domains. Herein, the design and synthesis of two bipyridyl and terpyridyl ruthenium(II) building units L1 and L2 are explained. A [Ru(bpy)3]2+ functionalized triangle S1 and a Sierpinski triangle S2 were synthesized in almost quantitative yields by the self-assembly of L1 with Zn2+ ions and by the heteroleptic self-assembly of L1 and L2 with Zn2+ ions, respectively. The Sierpinski triangle S2 contains the coordination metals [Ru(bpy)3]2+, [Ru(tpy)2]2+, and [Zn(tpy)2]2+. According to research on the catalytic activity of amine oxidation on supramolecules S1 and S2, the benzylamine substrates were nearly entirely transformed to N-benzylidenebenzylamine derivatives after 1 h under a Xe lamp. Furthermore, the observed ruthenium-containing terpyridyl supramolecule S2 maintains high luminous performance at ambient temperature. This discovery opens up new possibilities for the rational molecular design of terpyridyl ruthenium fluorescent materials and catalytic functional materials.

11.
Dalton Trans ; 52(21): 7071-7078, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-37161840

RESUMEN

In the field of metallo-supramolecular assemblies, supramolecular macrocycles have attracted considerable attention due to their guest recognition and catalytic properties. Herein, we report a novel strategy for the construction of giant hollow macrocyclic structures using a bi-directional geometric constraint strategy. We investigated the structural design of two terpyridine-based tetratopic organic ligands, whose inner and outer rims have different angles. Compared to conventional strategies of self-assembly using single angular orientation building blocks that typically generate small macrocyclic objects or polymers, the mutual interaction between the different angles of the ligands could promote the formation of giant hollow macrocyclic supramolecular architectures. The self-assembly mechanism and hierarchical self-assembly of giant supramolecular macrocycles have been characterized by NMR, ESI-MS and TEM experiments. The strategy used in this study not only advances the design of giant 2D macrocycles with large inner diameters but also gives insights into the mechanism of formation of large structures.

12.
Adv Mater ; 35(22): e2300352, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36906929

RESUMEN

All-perovskite tandem solar cells (TSCs) hold great promise in terms of ultrahigh efficiency, low manufacturing cost, and flexibility, stepping forward to the next-generation photovoltaics. However, their further development is hampered by the relatively low performance of low-bandgap (LBG) tin (Sn)-lead (Pb) perovskite solar cells (PSCs). Improving the carrier management, including suppressing trap-assisted non-radiative recombination and promoting carrier transfer, is of great significance to enhance the performance of Sn-Pb PSCs. Herein, a carrier management strategy is reported for using cysteine hydrochloride (CysHCl) simultaneously as a bulky passivator and a surface anchoring agent for Sn-Pb perovskite. CysHCl processing effectively reduces trap density and suppresses non-radiative recombination, enabling the growth of high-quality Sn-Pb perovskite with greatly improved carrier diffusion length of >8 µm. Furthermore, the electron transfer at the perovskite/C60 interface is accelerated due to the formation of surface dipoles and favorable energy band bending. As a result, these advances enable the demonstration of champion efficiency of 22.15% for CysHCl-processed LBG Sn-Pb PSCs with remarkable enhancement in both open-circuit voltage and fill factor. When paired with a wide-bandgap (WBG) perovskite subcell, a certified 25.7%-efficient all-perovskite monolithic tandem device is further demonstrated.

13.
Nature ; 618(7963): 80-86, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36990110

RESUMEN

All-perovskite tandem solar cells provide high power conversion efficiency at a low cost1-4. Rapid efficiency improvement in small-area (<0.1 cm2) tandem solar cells has been primarily driven by advances in low-bandgap (approximately 1.25 eV) perovskite bottom subcells5-7. However, unsolved issues remain for wide-bandgap (> 1.75 eV) perovskite top subcells8, which at present have large voltage and fill factor losses, particularly for large-area (>1 cm2) tandem solar cells. Here we develop a self-assembled monolayer of (4-(7H-dibenzo[c,g]carbazol-7-yl)butyl)phosphonic acid as a hole-selective layer for wide-bandgap perovskite solar cells, which facilitates subsequent growth of high-quality wide-bandgap perovskite over a large area with suppressed interfacial non-radiative recombination, enabling efficient hole extraction. By integrating (4-(7H-dibenzo[c,g]carbazol-7-yl)butyl)phosphonic acid in devices, we demonstrate a high open-circuit voltage (VOC) of 1.31 V in a 1.77-eV perovskite solar cell, corresponding to a very low VOC deficit of 0.46 V (with respect to the bandgap). With these wide-bandgap perovskite subcells, we report 27.0% (26.4% certified stabilized) monolithic all-perovskite tandem solar cells with an aperture area of 1.044 cm2. The certified tandem cell shows an outstanding combination of a high VOC of 2.12 V and a fill factor of 82.6%. Our demonstration of the large-area tandem solar cells with high certified efficiency is a key step towards scaling up all-perovskite tandem photovoltaic technology.

14.
Brain Sci ; 13(3)2023 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-36979287

RESUMEN

Clinical studies have shown that speech pauses can reflect the cognitive function differences between Alzheimer's Disease (AD) and non-AD patients, while the value of pause information in AD detection has not been fully explored. Herein, we propose a speech pause feature extraction and encoding strategy for only acoustic-signal-based AD detection. First, a voice activity detection (VAD) method was constructed to detect pause/non-pause feature and encode it to binary pause sequences that are easier to calculate. Then, an ensemble machine-learning-based approach was proposed for the classification of AD from the participants' spontaneous speech, based on the VAD Pause feature sequence and common acoustic feature sets (ComParE and eGeMAPS). The proposed pause feature sequence was verified in five machine-learning models. The validation data included two public challenge datasets (ADReSS and ADReSSo, English voice) and a local dataset (10 audio recordings containing five patients and five controls, Chinese voice). Results showed that the VAD Pause feature was more effective than common feature sets (ComParE: 6373 features and eGeMAPS: 88 features) for AD classification, and that the ensemble method improved the accuracy by more than 5% compared to several baseline methods (8% on the ADReSS dataset; 5.9% on the ADReSSo dataset). Moreover, the pause-sequence-based AD detection method could achieve 80% accuracy on the local dataset. Our study further demonstrated the potential of pause information in speech-based AD detection, and also contributed to a more accessible and general pause feature extraction and encoding method for AD detection.

15.
Radiology ; 307(3): e220996, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36880944

RESUMEN

Background Studies have rarely investigated stenosis detection from head and neck CT angiography scans because accurate interpretation is time consuming and labor intensive. Purpose To develop an automated convolutional neural network-based method for accurate stenosis detection and plaque classification in head and neck CT angiography images and compare its performance with that of radiologists. Materials and Methods A deep learning (DL) algorithm was constructed and trained with use of head and neck CT angiography images that were collected retrospectively from four tertiary hospitals between March 2020 and July 2021. CT scans were partitioned into training, validation, and independent test sets at a ratio of 7:2:1. An independent test set of CT angiography scans was collected prospectively between October 2021 and December 2021 in one of the four tertiary centers. Stenosis grade categories were as follows: mild stenosis (<50%), moderate stenosis (50%-69%), severe stenosis (70%-99%), and occlusion (100%). The stenosis diagnosis and plaque classification of the algorithm were compared with the ground truth of consensus by two radiologists (with more than 10 years of experience). The performance of the models was analyzed in terms of accuracy, sensitivity, specificity, and areas under the receiver operating characteristic curve. Results There were 3266 patients (mean age ± SD, 62 years ± 12; 2096 men) evaluated. The consistency between radiologists and the DL-assisted algorithm on plaque classification was 85.6% (320 of 374 cases [95% CI: 83.2, 88.6]) on a per-vessel basis. Moreover, the artificial intelligence model assisted in visual assessment, such as increasing confidence in the degree of stenosis. This reduced the time needed for diagnosis and report writing of radiologists from 28.8 minutes ± 5.6 to 12.4 minutes ± 2.0 (P < .001). Conclusion A deep learning algorithm for head and neck CT angiography interpretation accurately determined vessel stenosis and plaque classification and had equivalent diagnostic performance when compared with experienced radiologists. © RSNA, 2023 Supplemental material is available for this article.


Asunto(s)
Angiografía por Tomografía Computarizada , Aprendizaje Profundo , Masculino , Humanos , Inteligencia Artificial , Estudios Retrospectivos , Constricción Patológica
16.
Science ; 379(6633): 690-694, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36795809

RESUMEN

Lewis base molecules that bind undercoordinated lead atoms at interfaces and grain boundaries (GBs) are known to enhance the durability of metal halide perovskite solar cells (PSCs). Using density functional theory calculations, we found that phosphine-containing molecules have the strongest binding energy among members of a library of Lewis base molecules studied herein. Experimentally, we found that the best inverted PSC treated with 1,3-bis(diphenylphosphino)propane (DPPP), a diphosphine Lewis base that passivates, binds, and bridges interfaces and GBs, retained a power conversion efficiency (PCE) slightly higher than its initial PCE of ~23% after continuous operation under simulated AM1.5 illumination at the maximum power point and at ~40°C for >3500 hours. DPPP-treated devices showed a similar increase in PCE after being kept under open-circuit conditions at 85°C for >1500 hours.

17.
Dalton Trans ; 52(10): 3033-3039, 2023 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-36779408

RESUMEN

A series of complexes L22-M (L2: 6,6″-bis(4-methoxyphenyl)-4'-phenyl-2,2':6',2″-terpyridine, M: Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+) were synthesized by coordinating p-methoxyphenyl 6,6″-substituted terpyridine ligand with first-row transition metal ions and characterized by NMR, ESI-MS, and X-ray single crystal diffraction techniques. Single-crystal structures demonstrated that the steric hindrance of p-methoxyphenyl substituents endowed complexes L22-M with obvious longer coordination bond lengths and larger bond angles and dihedral angles compared with unmodified L12-M (L1: 4'-phenyl-2,2':6',2″-terpyridine). The chiral helix geometry was observed for L22-M, in which 2,2':6',2″-terpyridine moiety dramatically twisted to a spiral form in comparison to the nearly coplanar structure of the parent L12-M, resulting in plentiful intramolecular and intermolecular π-π interactions. Also, the appealing racemic (P and M) double helix packed structure for 6,6″-modified bisterpyridine complex L22-Cu was formed in the crystal. The consequent appealing charge transfer (CT) emission for L22-Zn in the solution and solid were investigated via UV-vis and fluorescence spectroscopy techniques and time-dependent density functional theory (TD-DFT) calculations. This work afforded a new method to achieve intriguing chiral geometry and CT optical properties via the subtle design and modification of terpyridine ligands.

18.
Artículo en Inglés | MEDLINE | ID: mdl-36758226

RESUMEN

Tin fluoride (SnF2) is an indispensable additive for high-efficiency Pb-Sn perovskite solar cells (PSCs). However, the spatial distribution of SnF2 in the perovskite absorber is seldom investigated while essential for a comprehensive understanding of the exact role of the SnF2 additive. Herein, we revealed the spatial distribution of the SnF2 additive and made structure-optoelectronic properties-flexible photovoltaic performance correlation. We observed the chemical transformation of SnF2 to a fluorinated oxy-phase on the Pb-Sn perovskite film surface due to its rapid oxidation. In addition, at the buried perovskite interface, we detected and visualized the accumulation of F- ions. We found that the photoluminescence quantum yield of Pb-Sn perovskite reached the highest value with 10 mol % SnF2 in the precursor solution. When integrating the optimized absorber in flexible devices, we obtained the flexible Pb-Sn perovskite narrow bandgap (1.24 eV) solar cells with an efficiency of 18.5% and demonstrated 23.1% efficient flexible four-terminal all-perovskite tandem cells.

19.
Neural Regen Res ; 18(7): 1521-1526, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36571357

RESUMEN

The adult cortex has long been regarded as non-neurogenic. Whether injury can induce neurogenesis in the adult cortex is still controversial. Here, we report that focal ischemia stimulates a transient wave of local neurogenesis. Using 5'-bromo-2'-deoxyuridine labeling, we demonstrated a rapid generation of doublecortin-positive neuroblasts that died quickly in mouse cerebral cortex following ischemia. Nestin-CreER-based cell ablation and fate mapping showed a small contribution of neuroblasts by subventricular zone neural stem cells. Using a mini-photothrombotic ischemia mouse model and retrovirus expressing green fluorescent protein labeling, we observed maturation of locally generated new neurons. Furthermore, fate tracing analyses using PDGFRα-, GFAP-, and Sox2-CreER mice showed a transient wave of neuroblast generation in mild ischemic cortex and identified that Sox2-positive astrocytes were the major neurogenic cells in adult cortex. In addition, a similar upregulation of Sox2 and appearance of neuroblasts were observed in the focal ischemic cortex of Macaca mulatta. Our findings demonstrated a transient neurogenic response of Sox2-positive astrocytes in ischemic cortex, which suggests the possibility of inducing neuronal regeneration by amplifying this intrinsic response in the future.

20.
J Colloid Interface Sci ; 631(Pt B): 44-54, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36395628

RESUMEN

Construction of Z-scheme heterojunction photocatalysts with efficient electron-hole pairs separation and robust oxidation abilities is a promising strategy to decompose volatile organic compounds (VOCs). Herein, UV-light-driven BiOCl and visible-light-driven Bi2WO6 were successfully combined via a one-pot hydrothermal method and compact Z-scheme heterojunction photocatalyst BiOCl/Bi2WO6 was obtained. Owing to the similar precursors and synthesis conditions, the integrated BiOCl/Bi2WO6 heterojunction was intimate and homogenous, which resulted in the efficient separation of photogenerated carriers, and generated abundant holes (h+), hydroxyl radicals (·OH) and superoxide radicals (·O2-). The optimal BiOCl/Bi2WO6 photocatalyst (BWOCl-2), achieved by tailoring the amount of hydrochloric acid, exhibited almost 100 % of toluene degradation and excellent durability. Electron spin resonance (ESR) results revealed that h+, ·O2- and ·OH were dominant active species in the BiOCl/Bi2WO6 photocatalytic system. The degradation intermediate products were monitored by in situ Diffuse Reflection Infrared Fourier Transform spectroscopy (DRIFTS) and the possible photocatalytic mechanism was also revealed according to the band structure of BiOCl/Bi2WO6 heterojunction. This work provided a novel avenue to design an efficient homogenous heterojunction photocatalyst for the efficient degradation of VOCs under sunlight.

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