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1.
Int J Biol Macromol ; 268(Pt 2): 130853, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38570000

RESUMO

BACKGROUND: Pulmonary hypertension (PH) is a complex vascular disorder, characterized by pulmonary vessel remodeling and perivascular inflammation. Pulmonary arterial smooth muscle cells (PASMCs) pyroptosis is a novel pathological mechanism implicated of pulmonary vessel remodeling. However, the involvement of circRNAs in the process of pyroptosis and the underlying regulatory mechanisms remain inadequately understood. METHODS: Western blotting, PI staining and LDH release were used to explore the role of circLrch3 in PASMCs pyroptosis. Moreover, S9.6 dot blot and DRIP-PCR were used to assess the formation of R-loop between circLrch3 and its host gene Lrch3. Chip-qPCR were used to evaluate the mechanism of super enhancer-associated circLrh3, which is transcriptionally activated by the transcription factor Tbx2. RESULTS: CircLrch3 was markedly upregulated in hypoxic PASMCs. CircLrch3 knockdown inhibited hypoxia induced PASMCs pyroptosis in vivo and in vitro. Mechanistically, circLrch3 can form R-loop with host gene to upregulate the protein and mRNA expression of Lrch3. Furthermore, super enhancer interacted with the Tbx2 at the Lrch3 promoter locus, mediating the augmented transcription of circLrch3. CONCLUSION: Our findings clarify the role of a super enhancer-associated circLrch3 in the formation of R-loop with the host gene Lrch3 to modulate pyroptosis in PASMCs, ultimately promoting the development of PH.


Assuntos
Miócitos de Músculo Liso , Artéria Pulmonar , Piroptose , RNA Circular , Piroptose/genética , RNA Circular/genética , RNA Circular/metabolismo , Animais , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Miócitos de Músculo Liso/metabolismo , Ratos , Proteínas com Domínio T/genética , Proteínas com Domínio T/metabolismo , Hipóxia Celular/genética , Músculo Liso Vascular/metabolismo , Masculino , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/patologia , Regulação da Expressão Gênica , Elementos Facilitadores Genéticos/genética , Hipóxia/genética , Hipóxia/metabolismo , Super Intensificadores
2.
Acta Pharmacol Sin ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632318

RESUMO

Frizzled receptors (FZDs) are key contributors intrinsic to the Wnt signaling pathway, activation of FZDs triggering the Wnt signaling cascade is frequently observed in human tumors and intimately associated with an aggressive carcinoma phenotype. It has been shown that the abnormal expression of FZD receptors contributes to the manifestation of malignant characteristics in human tumors such as enhanced cell proliferation, metastasis, chemotherapy resistance as well as the acquisition of cancer stemness. Given the essential roles of FZD receptors in the Wnt signaling in human tumors, this review aims to consolidate the prevailing knowledge on the specific status of FZD receptors (FZD1-10) and elucidate their respective functions in tumor progression. Furthermore, we delineate the structural basis for binding of FZD and its co-receptors to Wnt, and provide a better theoretical foundation for subsequent studies on related mechanisms. Finally, we describe the existing biological classes of small molecule-based FZD inhibitors in detail in the hope that they can provide useful assistance for design and development of novel drug candidates targeted FZDs.

3.
J Clin Transl Hepatol ; 12(4): 333-345, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38638378

RESUMO

Background and Aims: The global prevalence of nonalcoholic fatty liver disease (NAFLD) is 25%. This study aimed to explore differences in the gut microbial community and blood lipids between normal livers and those affected by NAFLD using 16S ribosomal deoxyribonucleic acid sequencing. Methods: Gut microbiome profiles of 40 NAFLD and 20 non-NAFLD controls were analyzed. Information about four blood lipids and 13 other clinical features was collected. Patients were divided into three groups by ultrasound and FibroScan, those with a normal liver, mild FL (FL1), and moderate-to-severe FL (FL2). FL1 and FL2 patients were divided into two groups, those with either hyperlipidemia or non-hyperlipidemia based on their blood lipids. Potential keystone species within the groups were identified using univariate analysis and a specificity-occupancy plot. Significant difference in biochemical parameters ion NAFLD patients and healthy individuals were identified by detrended correspondence analysis and canonical correspondence analysis. Results: Decreased gut bacterial diversity was found in patients with NAFLD. Firmicutes/Bacteroidetes decreased as NAFLD progressed. Faecalibacterium and Ruminococcus 2 were the most representative fatty-related bacteria. Glutamate pyruvic transaminase, aspartate aminotransferase, and white blood cell count were selected as the most significant biochemical indexes. Calculation of areas under the curve identified two microbiomes combined with the three biochemical indexes that identified normal liver and FL2 very well but performed poorly in diagnosing FL1. Conclusions: Faecalibacterium and Ruminococcus 2, combined with glutamate pyruvic transaminase, aspartate aminotransferase, and white blood cell count distinguished NAFLD. We speculate that regulating the health of gut microbiota may release NAFLD, in addition to providing new targets for clinicians to treat NAFLD.

4.
Adv Mater ; : e2401094, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684182

RESUMO

Intra-articular injection of drugs is an effective strategy for osteoarthritis (OA) treatment. However, the complex microenvironment and limited joint space result in rapid clearance of drugs. Herein, a nanogel-based strategy was proposed for prolonged drug delivery and microenvironment remodeling. Nanogel was constructed through functionalization of hyaluronic acid (HA) by amide reaction on the surface of Kartogenin (KGN)-loaded zeolitic imidazolate framework-8 (denoted as KZIF@HA). Leveraging the inherent hydrophilicity of HA, KZIF@HA spontaneously forms nanogels, ensuring extended drug release in the OA microenvironment. KZIF@HA exhibits sustained drug release over one month, with low leakage risk from the joint cavity compared to KZIF, enhanced cartilage penetration, and reparative effects on chondrocytes. Notably, KGN released from KZIF@HA serves to promote extracellular matrix (ECM) secretion for hyaline cartilage regeneration. Zn2+ release reverses OA progression by promoting M2 macrophage polarization to establish an anti-inflammatory microenvironment. Ultimately, KZIF@HA facilitates cartilage regeneration and OA alleviation within three months. Transcriptome sequencing validates that KZIF@HA stimulates the polarization of M2 macrophages and secretes IL-10 to inhibit the JNK and ERK pathways, promoting chondrocytes recovery and enhancing ECM remodeling. This pioneering nanogel system offers new therapeutic opportunities for sustained drug release, presenting a significant stride in OA treatment strategies. This article is protected by copyright. All rights reserved.

5.
Chem Commun (Camb) ; 60(17): 2261-2282, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38318641

RESUMO

Porous organic cages (POCs) represent a notable category of porous materials, showing remarkable material properties due to their inherent porosity. Unlike extended frameworks which are constructed by strong covalent or coordination bonds, POCs are composed of discrete molecular units held together by weak intermolecular forces. Their structure and chemical traits can be systematically tailored, making them suitable for a range of applications including gas storage and separation, molecular separation and recognition, catalysis, and proton and ion conduction. This review provides a comprehensive overview of POCs, covering their synthesis methods, structure and properties, computational approaches, and applications, serving as a primer for those who are new to the domain. A special emphasis is placed on the growing role of computational methods, highlighting how advanced data-driven techniques and automation are increasingly aiding the rapid exploration and understanding of POCs. We conclude by addressing the prevailing challenges and future prospects in the field.

6.
ACS Appl Mater Interfaces ; 16(13): 15916-15930, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38416419

RESUMO

Photodynamic therapy's antitumor efficacy is hindered by the inefficient generation of reactive oxygen species (ROS) due to the photogenerated electron-hole pairs recombination of photosensitizers (PS). Therefore, there is an urgent need to develop efficient PSs with enhanced carrier dynamics. Herein, we designed Schottky junctions composed of cobalt tetroxide and palladium nanocubes (Co3O4@Pd) with a built-in electric field as effective PS. The built-in electric field enhanced photogenerated charge separation and migration, resulting in the generation of abundant electron-hole pairs and allowing effective production of ROS. Thanks to the built-in electric field, the photocurrent intensity and carrier lifetime of Co3O4@Pd were approximately 2 and 3 times those of Co3O4, respectively. Besides, the signal intensity of hydroxyl radical and singlet oxygen increased to 253.4% and 135.9%, respectively. Moreover, the localized surface plasmon resonance effect of Pd also enhanced the photothermal conversion efficiency of Co3O4@Pd to 40.50%. In vitro cellular level and in vivo xenograft model evaluations demonstrated that Co3O4@Pd could generate large amounts of ROS, trigger apoptosis, and inhibit tumor growth under near-infrared laser irradiation. Generally, this study reveals the contribution of the built-in electric field to improving photodynamic performance and provides new ideas for designing efficient inorganic PSs.


Assuntos
Cobalto , Neoplasias , Óxidos , Fotoquimioterapia , Humanos , Espécies Reativas de Oxigênio , Fármacos Fotossensibilizantes/farmacologia , Neoplasias/tratamento farmacológico , Raios Infravermelhos
7.
Proc Natl Acad Sci U S A ; 121(9): e2315956121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38377201

RESUMO

Photo-catalytic CO2 reduction with perovskite quantum dots (QDs) shows potential for solar energy storage, but it encounters challenges due to the intricate multi-electron photoreduction processes and thermodynamic and kinetic obstacles associated with them. This study aimed to improve photo-catalytic performance by addressing surface barriers and utilizing multiple-exciton generation in perovskite QDs. A facile surface engineering method was employed, involving the grafting of ferrocene carboxylic acid (FCA) onto CsPbBr3 (CPB) QDs, to overcome limitations arising from restricted multiple-exciton dissociation and inefficient charge transfer dynamics. Kelvin Probe Force Microscopy and XPS spectral confirmed successfully creating an FCA-modulated microelectric field through the Cs active site, thus facilitating electron transfer, disrupting surface barrier energy, and promoting multi-exciton dissociations. Transient absorption spectroscopy showed enhanced charge transfer and reduced energy barriers, resulting in an impressive CO2-to-CO conversion rate of 132.8 µmol g-1 h-1 with 96.5% selectivity. The CPB-FCA catalyst exhibited four-cycle reusability and 72 h of long-term stability, marking a significant nine-fold improvement compared to pristine CPB (14.4 µmol g-1 h-1). These results provide insights into the influential role of FCA in regulating intramolecular charge transfer, enhancing multi-exciton dissociation, and improving CO2 photoreduction on CPB QDs. Furthermore, these findings offer valuable knowledge for controlling quantum-confined exciton dissociation to enhance CO2 photocatalysis.

8.
Mol Neurobiol ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321351

RESUMO

Brain-derived estrogen (BDE2) is gaining attention as an endogenous neurotransmitter. Recent research has revealed that selectively removing the aromatase gene, the pivotal enzyme responsible for BDE2 synthesis, in forebrain neurons or astrocytes can lead to synaptic loss and cognitive impairment. It is worth noting that remote ischemia post-conditioning (RIP), a non-invasive technique, has been shown to activate natural protective mechanisms against severe ischemic events. The aim of our study was to investigate whether RIP triggers aromatase-BDE2 signaling, shedding light on its neuroprotective mechanisms after global cerebral ischemia (GCI) in ovariectomized rats. Our findings are as follows: (1) RIP was effective in mitigating ischemic damage in hippocampal CA1 neurons and improved cognitive function after GCI. This was partially due to increased Aro-BDE2 signaling in CA1 neurons. (2) RIP intervention efficiently enhanced pro-survival kinase pathways, such as AKT, ERK1/2, CREB, and suppressed CaMKIIα signaling in CA1 astrocytes induced by GCI. Remarkably, inhibiting CaMKIIα activity led to elevated Aro-BDE2 levels and replicated the benefits of RIP. (3) We also identified the positive mediation of Cav1.2, an LVGCC calcium channel, on CaMKIIα-Aro/BDE2 pathway response to RIP intervention. (4) Significantly, either RIP or CaMKIIα inhibition was found to alleviate reactive astrogliosis, which was accompanied by increased pro-survival A2-astrocyte protein S100A10 and decreased pro-death A1-astrocyte marker C3 levels. In summary, our study provides compelling evidence that Aro-BDE2 signaling is a critical target for the reparative effects of RIP following ischemic insult. This effect may be mediated through the CaV1.2-CaMKIIα signaling pathway, in collaboration with astrocyte-neuron interactions, thereby maintaining calcium homeostasis in the neuronal microenvironment and reducing neuronal damage after ischemia.

9.
CNS Neurosci Ther ; 30(2): e14613, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38379185

RESUMO

AIMS: Alzheimer's disease (AD) is a significant global health concern, and it is crucial that we find effective methods to prevent or slow down AD progression. Recent studies have highlighted the essential role of blood vessels in clearing Aß, a protein that contributes to AD. Scientists are exploring blood biomarkers as a potential tool for future AD diagnosis. One promising method that may help prevent AD is remote ischemic conditioning (RIC). RIC involves using sub-lethal ischemic-reperfusion cycles on limbs. However, a comprehensive understanding of how RIC can prevent AD and its long-term effectiveness is still lacking. Further research is essential to fully comprehend the potential benefits of RIC in preventing AD. METHODS: Female wild-type (WT) and APP/PS1 transgenic rats, aged 12 months, underwent ovariectomy and were subsequently assigned to WT, APP/PS1, and APP/PS1 + RIC groups. RIC was conducted five times a week for 4 weeks. The rats' depressive and cognitive behaviors were evaluated using force swimming, open-field tests, novel objective recognition, elevated plus maze, and Barnes maze tests. Evaluation of the neurovascular unit (NVU), synapses, vasculature, astrocytes, and microglia was conducted using immunofluorescence staining (IF), Western blot (WB), and transmission electron microscopy (TEM). Additionally, the cerebro-vasculature was examined using micro-CT, and cerebral blood flow (CBF) was measured using Speckle Doppler. Blood-brain barrier (BBB) permeability was determined by measuring the Evans blue leakage. Finally, Aß levels in the rat frontal cortex were measured using WB, ELISA, or IF staining. RESULTS: RIC enhanced memory-related protein expression and rescued depressive-like behavior and cognitive decline in APP/PS1 transgenic rats. Additionally, the intervention protected NVU in the rat frontal cortex, as evidenced by (1) increased expression of TJ (tight junction) proteins, pericyte marker PDGFRß, and glucose transporter 1 (GLUT1), as well as decreased VCAM1; (2) mitigation of ultrastructure impairment in neuron, cerebral vascular, and astrocyte; (3) upregulation of A2 astrocyte phenotype markers and downregulation of A1 phenotype markers, indicating a shift toward a healthier phenotype. Correspondingly, RIC intervention alleviated neuroinflammation, as evidenced by the decreased Iba1 level, a microglia marker. Meanwhile, RIC intervention elevated CBF in frontal cortex of the rats. Notably, RIC intervention effectively suppressed Aß toxicity, as demonstrated by the enhancement of α-secretase and attenuation of ß-secretase (BACE1) and γ- secretase and Aß1-42 and Aß1-40 levels as well. CONCLUSION: Chronic RIC intervention exerts vascular and neuroprotective roles, suggesting that RIC could be a promising therapeutic strategy targeting the BBB and NVU during AD development.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Camundongos , Ratos , Feminino , Animais , Barreira Hematoencefálica/metabolismo , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Camundongos Transgênicos , Ratos Transgênicos , Ácido Aspártico Endopeptidases/genética , Ácido Aspártico Endopeptidases/metabolismo , Ácido Aspártico Endopeptidases/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/terapia , Modelos Animais de Doenças , Presenilina-1/genética , Presenilina-1/metabolismo
10.
Front Aging Neurosci ; 16: 1304852, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38371401

RESUMO

Background: Freezing of gait (FOG) is one of the most disabling gait disturbances in Parkinson's disease (PD), affecting mobility and balance severely, thereby leading to an increased risk of falls. Objectives: The purpose of this systematic review and meta-analysis was to investigate the effects of transcranial magnetic stimulation on FOG in PD. Methods: Based on PRISMA guidelines, we searched the databases of MEDLINE (PubMed), Cochrane Library, PEDro, Embase, and Web of Science. Studies of the English language published up to July 2023 were searched. We retrieved for studies of randomized controlled trials (RCTs) of transcranial magnetic stimulation to treat FOG after PD and screened by inclusion and exclusion criteria. Risk of bias was assessed using the Cochrane Collaboration's tool (Revman5.30). Characteristics of RCTs were extracted. The heterogeneity of the trials was measured by I2 statistic. The effect size was expressed by a standardized mean difference (SMD) with a 95% confidence interval (CI). Results: A total of 488 articles were screened, after screening sixteen RCTs involved in 408 patients were included in the qualitative analysis, and 15 RCTs were included in meta-analysis. The outcome measures included FOG-Q, walking time, TUG, and UPDRS. Six studies used FOG-Q as outcome measure, six studies used walking time, four studies used TUG, and six studies used UPDRS. Compared with placebo treatment, transcranial magnetic stimulation has positive significant effects in improving gait status with increased walking speed (SMD = -0.41, 95% CI = -0.75 to -0.06, I2 = 7% p = 0.02), FOG-Q scores (SMD = -0.55, 95% CI = -0.89 to -0.21, I2 = 29%, p = 0.002), UPDRS scores (SMD = -1.08, 95% CI = -1.39 to -0.78, I2 = 49%, P < 0.001) and the time of TUG (SMD = -0.56, 95% CI = -0.88 to -0.23, I2 = 25%, p = 0.02) decreased. Conclusion: Transcranial magnetic stimulation could significantly improving gait conditions in PD patients with FOG. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO/#recordDetails, CRD42023434286.

11.
Glob Chang Biol ; 30(1): e17138, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38273499

RESUMO

Water availability (WA) is a key factor influencing the carbon cycle of terrestrial ecosystems under climate warming, but its effects on gross primary production (EWA-GPP ) at multiple time scales are poorly understood. We used ensemble empirical mode decomposition (EEMD) and partial correlation analysis to assess the WA-GPP relationship (RWA-GPP ) at different time scales, and geographically weighted regression (GWR) to analyze their temporal dynamics from 1982 to 2018 with multiple GPP datasets, including near-infrared radiance of vegetation GPP, FLUXCOM GPP, and eddy covariance-light-use efficiency GPP. We found that the 3- and 7-year time scales dominated global WA variability (61.18% and 11.95%), followed by the 17- and 40-year time scales (7.28% and 8.23%). The long-term trend also influenced 10.83% of the regions, mainly in humid areas. We found consistent spatiotemporal patterns of the EWA-GPP and RWA-GPP with different source products: In high-latitude regions, RWA-GPP changed from negative to positive as the time scale increased, while the opposite occurred in mid-low latitudes. Forests had weak RWA-GPP at all time scales, shrublands showed negative RWA-GPP at long time scales, and grassland (GL) showed a positive RWA-GPP at short time scales. Globally, the EWA-GPP , whether positive or negative, enhanced significantly at 3-, 7-, and 17-year time scales. For arid and humid zones, the semi-arid and sub-humid zones experienced a faster increase in the positive EWA-GPP , whereas the humid zones experienced a faster increase in the negative EWA-GPP . At the ecosystem types, the positive EWA-GPP at a 3-year time scale increased faster in GL, deciduous broadleaf forest, and savanna (SA), whereas the negative EWA-GPP at other time scales increased faster in evergreen needleleaf forest, woody savannas, and SA. Our study reveals the complex and dynamic EWA-GPP at multiple time scales, which provides a new perspective for understanding the responses of terrestrial ecosystems to climate change.


Assuntos
Ecossistema , Água , Florestas , Ciclo do Carbono , Mudança Climática
12.
Proc Natl Acad Sci U S A ; 121(5): e2320237121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38252821

RESUMO

Dynamic 3D covalent organic frameworks (COFs) have shown concerted structural transformation and adaptive gas adsorption due to the conformational diversity of organic linkers. However, the isolation and observation of COF rotamers constitute undergoing challenges due to their comparable free energy and subtle rotational energy barrier. Here, we report the atomic-level observation and structural evolution of COF rotamers by cryo-3D electron diffraction and synchrotron powder X-ray diffraction. Specifically, we optimize the crystallinity and morphology of COF-320 to manifest its coherent dynamic responses upon adaptive inclusion of guest molecules. We observe a significant crystal expansion of 29 vol% upon hydration and a giant swelling with volume change up to 78 vol% upon solvation. We record the structural evolution from a non-porous contracted phase to two narrow-pore intermediate phases and the fully opened expanded phase using n-butane as a stabilizing probe at ambient conditions. We uncover the rotational freedom of biphenylene giving rise to significant conformational changes on the diimine motifs from synclinal to syn-periplanar and anticlinal rotamers. We illustrate the 10-fold increment of pore volumes and 100% enhancement of methane uptake capacity of COF-320 at 100 bar and 298 K. The present findings shed light on the design of smarter organic porous materials to maximize host-guest interaction and boost gas uptake capacity through progressive structural transformation.

13.
Small ; 20(7): e2307087, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37802973

RESUMO

The free radical generation efficiency of nanozymes in cancer therapy is crucial, but current methods fall short. Alloy nanoparticles (ANs) hold promise for improving catalytic performance due to their inherent electronic effect, but there are limited ways to modulate this effect. Here, a self-driven electric field (E) system utilizing triboelectric nanogenerator (TENG) and AuPd ANs with glucose oxidase (GOx)-like, catalase (CAT)-like, and peroxidase (POD)-like activities is presented to enhance the treatment of 4T1 breast cancer in mice. The E stimulation from TENG enhances the orbital electrons of AuPd ANs, resulting in increased CAT-like, GOx-like, and POD-like activities. Meanwhile, the catalytic cascade reaction of AuPd ANs is further amplified after catalyzing the production of H2 O2 from the GOx-like activities. This leads to 89.5% tumor inhibition after treatment. The self-driven E strategy offers a new way to enhance electronic effects and improve cascade catalytic therapeutic performance of AuPd ANs in cancer therapy.


Assuntos
Nanopartículas , Neoplasias , Neoplasias Orbitárias , Animais , Camundongos , Elétrons , Neoplasias Orbitárias/tratamento farmacológico , Neoplasias/tratamento farmacológico , Glucose Oxidase , Peróxido de Hidrogênio
14.
Small ; 20(21): e2309704, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38100215

RESUMO

Single-atom nanozymes (SAzymes) are emerging natural enzyme mimics and have attracted much attention in the biomedical field. SAzymes with Metal─Nx sites designed on carbon matrixes are currently the mainstream in research. It is of great significance to further expand the types of SAzymes to enrich the nanozyme library. Single-atom alloys (SAAs) are a material in which single-atom metal sites are dispersed onto another active metal matrix, and currently, there is limited research on their enzyme-like catalytic performance. In this work, a biodegradable Pt1Pd SAA is fabricated via a simple galvanic replacement strategy, and for the first time reveals its intrinsic enzyme-like catalytic performance including catalase-, oxidase-, and peroxidase-like activities, as well as its photodynamic effect. Experimental characterizations demonstrate that the introduction of single-atom Pt sites contributes to enhancing the affinity of Pt1Pd single-atom alloy nanozyme (SAAzyme) toward substrates, thus exhibiting boosted catalytic efficiency. In vitro and in vivo experiments demonstrate that Pt1Pd SAAzyme exhibits a photo-controlled therapeutic effect, with a tumor inhibition rate of up to 100%. This work provides vital guidance for opening the research direction of SAAs in enzyme-like catalysis.


Assuntos
Ligas , Ligas/química , Animais , Platina/química , Humanos , Catálise , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Camundongos , Fototerapia/métodos
15.
Adv Mater ; 36(13): e2312024, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38101802

RESUMO

Single-atom nanozymes (SAzymes), with well-defined and uniform atomic structures, are an emerging type of natural enzyme mimics. Currently, it is important but challenging to rationally design high-performance SAzymes and deeply reveal the interaction mechanism between SAzymes and substrate molecules. Herein, this work reports the controllable fabrication of a unique Cu-N1S2-centred SAzyme (Cu-N/S-C) via a chemical vapor deposition-based sulfur-engineering strategy. Benefiting from the optimized geometric and electronic structures of single-atom sites, Cu-N/S-C SAzyme shows boosted enzyme-like activity, especially in catalase-like activity, with a 13.8-fold increase in the affinity to hydrogen peroxide (H2O2) substrate and a 65.2-fold increase in the catalytic efficiency when compared to Cu-N-C SAzyme with Cu-N3 sites. Further theoretical studies reveal that the increased electron density around single-atom Cu is achieved through electron redistribution, and the efficient charge transfer between Cu-N/S-C and H2O2 is demonstrated to be more beneficial for the adsorption and activation of H2O2. The as-designed Cu-N/S-C SAzyme possesses an excellent antitumor effect through the synergy of catalytic therapy and oxygen-dependent phototherapy. This study provides a strategy for the rational design of SAzymes, and the proposed electron redistribution and charge transfer mechanism will help to understand the coordination environment effect of single-atom metal sites on H2O2-mediated enzyme-like catalytic processes.


Assuntos
Peróxido de Hidrogênio , Neoplasias , Humanos , Engenharia , Engenharia Química , Fototerapia , Catálise , Gases , Neoplasias/terapia
16.
Dysphagia ; 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38117313

RESUMO

Stroke is the leading cause of death and disability among adults. The incidence of stroke per 100, 000 patient-years was 2875. As many as 37% to 78% of patients with acute strokes suffer dysphagia. Dysphagia can easily lead to inhalation pneumonia, dehydration, malnutrition, and other serious complications, affecting the quality of life of stroke patients and increasing their mortality. Effective prevention and treatment of post-stroke dysphagia are of great significance to improving the prognosis and quality of life of patients. Some studies have shown that Pharyngeal cavity electrical stimulation-assisted swallowing (PCES-assisted swallowing) has a positive effect on patients with post-stroke dysphagia. This study will evaluate the effects of PCES-assisted swallowing on post-stroke dysphagia, including swallowing function, withdrawal rate of nasal feeding tubes, duration of hospitalization, and so on. Randomized controlled trials (RCTs) of PCES-assisted swallowing in the treatment of post-stroke dysphagia were searched in eight databases, including Cochrane Library, Embase, PubMed, Web of Science, Chinese Biomedical Literature Database, VIP Information Resource System, CNKI, and Wanfang Medical Science. The retrieval time was from the database establishment to June 2022. Rayyan was used to screen the retrieved literature risk of bias for included studies and was calculated using ROB2.0. The RevMan 5.3 software was used for the meta-analysis with the standard mean difference (SMD) and 95% confidence interval (CI). The model type was a random effect model, The risk ratio (RR) was used as the effect size for the two categorical variables. The swallowing function scores, withdrawal rate of nasal feeding tubes, and Length of stay (LOS) of the intervention and control groups were extracted, and the results of the meta-analysis were presented using a forest plot. Six studies from 2010 to 2018 with a total of 341 people were included in the meta-analysis. All studies reported quantitative outcome measures for the severity of dysphagia, and some reported the withdrawal rate of nasal feeding tubes, LOS, and penetration-aspiration-scale (PAS). The overall swallowing function of the PCES group was better than that of the control group (SMD = - 0.20, 95%CI - 0.38 to - 0.03, P = 0.02). In terms of the severity of dysphagia, there was a statistically significant difference in the Dysphagia Severity Rating scale (DSRS) between the Pharyngeal cavity electrical stimulation (PCES) group and the control group (SMD = - 0.24, 95%CI - 0.48 to 0, P = 0.05). The PCES group nasal feeding withdrawal rate of nasal feeding tubes was higher than the control group (RR = 2.88, 95% CI 1.15 to 7.26, P = 0.02). There was no significant difference in the LOS between the PCES group and the control group (SMD = - 0.19, 95%CI - 0.44 to 0.07, P = 0.15). This systematic review and meta-analysis provide reasonably reliable evidence that PCES-assisted swallowing can improve nasogastric feeding swallowing function and the withdrawal rate of nasal feeding tubes in patients with post-stroke dysphagia. However, the evidence for reducing oral feeding, aspiration, and length of hospitalization stay is lacking, and further studies are needed.

17.
Front Neurol ; 14: 1285659, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38020596

RESUMO

Background: There are very few studies on transcranial magnetic stimulation (TMS) therapy for facial paralysis and no studies comparing the efficacy of central and peripheral TMS in the treatment of peripheral facial paralysis (PFP). Purpose: To observe the therapeutic effect and security of central and peripheral repetitive transcranial magnetic stimulation (rTMS) on PFP. Methods: Patients with unilateral onset of peripheral facial paralysis within 1 month were prospectively recruited, 97 patients with PFP were divided into the peripheral group, central group, and control group. The control group was given common treatment (drug therapy and acupuncture), and the peripheral and central groups received rTMS in addition to conventional treatment. After 2 weeks of treatment, the House-Brackmann (HB) grading scale, Sunnybrook facial grading system (SFGS), and modified Portmann scale (MPS) were used to evaluate the facial muscle function of patients in the three groups. Result: After 2 weeks of rTMS treatment, the HBGS/SFGS/MPS scores of the three groups were significantly better than before (p < 0.05), and the mean change values of HBGS, SFGS, and MPS scores were significantly higher in participants in Peripheral Group (p < 0.001; p < 0.001; p = 0.003; respectively) and Central Group (p = 0.004; p = 0.003; p = 0.009; respectively) than in Control Group. But the mean change values of HBGS, SFGS, and MPS scores showed no significant differences in participants in the Peripheral Group than in the Central Group (p = 0.254; p = 0.139; p = 0.736; respectively) after 2 weeks of treatment (p > 0.05). Conclusion: Our study shows that rTMS can be a safe and effective adjuvant therapy for patients with PFP. Preliminary studies have shown that both peripheral and central stimulation can effectively improve facial nerve function, but there is no significant difference in the efficacy of the two sites.

18.
Adv Healthc Mater ; : e2302714, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38029413

RESUMO

Despite preventive measures and available treatments, cervical cancer still ranks as the fourth most prevalent cancer among women worldwide and remains the leading cause of cancer death in women in many developing countries. To gain further insights into pathogenesis and to develop novel (immuno)therapies, more sophisticated human models recreating patient heterogeneities and including aspects of the tumor microenvironment are urgently required. A novel polydimethylsiloxane-free microfluidic platform, designed specifically for the generation and ccultivation of cervical cancerous tissue, is introduced. The microscale open-top tissue chambers of the cervical cancer-on-chip (CCoC) enable facile generation and long-term cultivation of SiHa spheroids in co-culture with donor-derived cervical fibroblasts. The resulting 3D tissue emulates physiological architecture and allows dissection of distinct effects of the stromal tissue on cancer viability and growth. Treatment with cisplatin at clinically-relevant routes of administration and dosing highlights the platform's applicability for drug testing. Moreover, the model is amenable for integration and recruitment of donor-derived neutrophils from the microvasculature-like channel into the tissue, all while retaining their ability to produce neutrophil extracellular traps. In the future, the immunocompetent CCoC featuring donor-specific primary cells and tumor spheroids has the potential to contribute to the development of new (immuno)therapeutic options.

19.
Signal Transduct Target Ther ; 8(1): 435, 2023 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-37996406

RESUMO

Mesoporous silica nanoparticles (MSNs) are recognized as a prime example of nanotechnology applied in the biomedical field, due to their easily tunable structure and composition, diverse surface functionalization properties, and excellent biocompatibility. Over the past two decades, researchers have developed a wide variety of MSNs-based nanoplatforms through careful design and controlled preparation techniques, demonstrating their adaptability to various biomedical application scenarios. With the continuous breakthroughs of MSNs in the fields of biosensing, disease diagnosis and treatment, tissue engineering, etc., MSNs are gradually moving from basic research to clinical trials. In this review, we provide a detailed summary of MSNs in the biomedical field, beginning with a comprehensive overview of their development history. We then discuss the types of MSNs-based nanostructured architectures, as well as the classification of MSNs-based nanocomposites according to the elements existed in various inorganic functional components. Subsequently, we summarize the primary purposes of surface-functionalized modifications of MSNs. In the following, we discuss the biomedical applications of MSNs, and highlight the MSNs-based targeted therapeutic modalities currently developed. Given the importance of clinical translation, we also summarize the progress of MSNs in clinical trials. Finally, we take a perspective on the future direction and remaining challenges of MSNs in the biomedical field.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas , Sistemas de Liberação de Medicamentos/métodos , Dióxido de Silício/química , Dióxido de Silício/uso terapêutico , Porosidade , Portadores de Fármacos/química , Nanopartículas/uso terapêutico , Nanopartículas/química
20.
Adv Mater ; 35(51): e2304514, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37784226

RESUMO

Bacterial pneumonia is the leading cause of death worldwide among all infectious diseases. However, currently available vaccines against fatal bacterial lung infections, e.g., pneumonic plague, are accompanied by limitations, including insufficient antigen-adjuvant co-delivery and inadequate immune stimulation. Therefore, there is an urgent requirement to develop next-generation vaccines to improve the interaction between antigen and adjuvant, as well as enhance the effects of immune stimulation. This study develops a novel amino-decorated mesoporous manganese silicate nanoparticle (AMMSN) loaded with rF1-V10 (rF1-V10@AMMSN) to prevent pneumonic plague. These results suggest that subcutaneous immunization with rF1-V10@AMMSN in a prime-boost strategy induces robust production of rF1-V10-specific IgG antibodies with a geometric mean titer of 315,844 at day 42 post-primary immunization, which confers complete protection to mice against 50 × LD50 of Yersinia pestis (Y. pestis) challenge via the aerosolized intratracheal route. Mechanistically, rF1-V10@AMMSN can be taken up by dendritic cells (DCs) and promote DCs maturation through activation of the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway and production of type I interferon. This process results in enhanced antigen presentation and promotes rF1-V10-mediated protection against Y. pestis infection. This manganese-based nanoparticle vaccine represents a valuable strategy for combating fatal bacterial pneumonia.


Assuntos
Vacina contra a Peste , Peste , Pneumonia Bacteriana , Vacinas , Camundongos , Animais , Peste/prevenção & controle , Nanovacinas , Manganês , Antígenos de Bactérias/genética , Pneumonia Bacteriana/prevenção & controle , Adjuvantes Imunológicos , Proteínas de Bactérias
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