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1.
N Engl J Med ; 388(14): 1272-1283, 2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-36762852

RESUMEN

BACKGROUND: The role of endovascular therapy for acute stroke with a large infarction has not been extensively studied in differing populations. METHODS: We conducted a multicenter, prospective, open-label, randomized trial in China involving patients with acute large-vessel occlusion in the anterior circulation and an Alberta Stroke Program Early Computed Tomography Score of 3 to 5 (range, 0 to 10, with lower values indicating larger infarction) or an infarct-core volume of 70 to 100 ml. Patients were randomly assigned in a 1:1 ratio within 24 hours from the time they were last known to be well to undergo endovascular therapy and receive medical management or to receive medical management alone. The primary outcome was the score on the modified Rankin scale at 90 days (scores range from 0 to 6, with higher scores indicating greater disability), and the primary objective was to determine whether a shift in the distribution of the scores on the modified Rankin scale at 90 days had occurred between the two groups. Secondary outcomes included scores of 0 to 2 and 0 to 3 on the modified Rankin scale. The primary safety outcome was symptomatic intracranial hemorrhage within 48 hours after randomization. RESULTS: A total of 456 patients were enrolled; 231 were assigned to the endovascular-therapy group and 225 to the medical-management group. Approximately 28% of the patients in both groups received intravenous thrombolysis. The trial was stopped early owing to the efficacy of endovascular therapy after the second interim analysis. At 90 days, a shift in the distribution of scores on the modified Rankin scale toward better outcomes was observed in favor of endovascular therapy over medical management alone (generalized odds ratio, 1.37; 95% confidence interval, 1.11 to 1.69; P = 0.004). Symptomatic intracranial hemorrhage occurred in 14 of 230 patients (6.1%) in the endovascular-therapy group and in 6 of 225 patients (2.7%) in the medical-management group; any intracranial hemorrhage occurred in 113 (49.1%) and 39 (17.3%), respectively. Results for the secondary outcomes generally supported those of the primary analysis. CONCLUSIONS: In a trial conducted in China, patients with large cerebral infarctions had better outcomes with endovascular therapy administered within 24 hours than with medical management alone but had more intracranial hemorrhages. (Funded by Covidien Healthcare International Trading [Shanghai] and others; ANGEL-ASPECT ClinicalTrials.gov number, NCT04551664.).


Asunto(s)
Isquemia Encefálica , Infarto Cerebral , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Trombectomía , Humanos , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/cirugía , Infarto Cerebral/tratamiento farmacológico , Infarto Cerebral/cirugía , China , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/métodos , Fibrinolíticos/efectos adversos , Fibrinolíticos/uso terapéutico , Hemorragias Intracraneales/inducido químicamente , Hemorragias Intracraneales/etiología , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/cirugía , Estudios Prospectivos , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/cirugía , Trombectomía/efectos adversos , Trombectomía/métodos , Resultado del Tratamiento
2.
Proc Natl Acad Sci U S A ; 120(20): e2220353120, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37155875

RESUMEN

Early-life stress has long-term impacts on the structure and function of the anterior cingulate cortex (ACC), and raises the risk of adult neuropsychiatric disorders including social dysfunction. The underlying neural mechanisms, however, are still uncertain. Here, we show that, in female mice, maternal separation (MS) during the first three postnatal weeks results in social impairment accompanied with hypoactivity in pyramidal neurons (PNs) of the ACC. Activation of ACC PNs ameliorates MS-induced social impairment. Neuropeptide Hcrt, which encodes hypocretin (orexin), is the top down-regulated gene in the ACC of MS females. Activating ACC orexin terminals enhances the activity of ACC PNs and rescues the diminished sociability observed in MS females via an orexin receptor 2 (OxR2)-dependent mechanism. Our results suggest orexin signaling in the ACC is critical in mediating early-life stress-induced social impairment in females.


Asunto(s)
Neuropéptidos , Estrés Psicológico , Animales , Femenino , Ratones , Giro del Cíngulo , Privación Materna , Neuropéptidos/metabolismo , Receptores de Orexina/genética , Orexinas/genética , Orexinas/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(45): e2309032120, 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37903267

RESUMEN

Tryptophan and its derivatives perform a variety of biological functions; however, the role and specific mechanism of many tryptophan derivatives in intestinal inflammation remain largely unclear. Here, we identified that an Escherichia coli strain (Ec-TMU) isolated from the feces of tinidazole-treated individuals, and indole-3-lactic acid (ILA) in its supernatant, decreased the susceptibility of mice to dextran sulfate sodium-induced colitis. Ec-TMU and ILA contribute to the relief of colitis by inhibiting the production of epithelial CCL2/7, thereby reducing the accumulation of inflammatory macrophages in vitro and in vivo. Mechanistically, ILA downregulates glycolysis, NF-κB, and HIF signaling pathways via the aryl hydrocarbon receptor, resulting in decreased CCL2/7 production in epithelial cells. Clinical evidence suggests that the fecal ILA level is negatively correlated with the progression indicator of inflammatory bowel diseases. These results demonstrate that ILA has the potential to regulate intestinal homeostasis by modulating epithelium-macrophage interactions.


Asunto(s)
Colitis , Triptófano , Animales , Ratones , Triptófano/metabolismo , Colitis/metabolismo , Macrófagos/metabolismo , Epitelio/metabolismo , Sulfato de Dextran/toxicidad , Ratones Endogámicos C57BL , Mucosa Intestinal/metabolismo
4.
FASEB J ; 38(13): e23701, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38941193

RESUMEN

Zearalenone (ZEN) is a mycotoxin known for its estrogen-like effects, which can disrupt the normal physiological function of endometrial cells and potentially lead to abortion in female animals. However, the precise mechanism by which ZEN regulates endometrial function remains unclear. In this study, we found that the binding receptor estrogen receptors for ZEN is extensively expressed across various segments of the uterus and within endometrial cells, and a certain concentration of ZEN treatment reduced the proliferation capacity of goat endometrial epithelial cells (EECs) and endometrial stromal cells (ESCs). Meanwhile, cell cycle analysis revealed that ZEN treatment leaded to cell cycle arrest in goat EECs and ESCs. To explore the underlying mechanism, we investigated the mitochondrial quality control systems and observed that ZEN triggered excessive mitochondrial fission and disturbed the balance of mitochondrial fusion-fission dynamics, impaired mitochondrial biogenesis, increased mitochondrial unfolded protein response and mitophagy in goat EECs and ESCs. Additionally, ZEN treatment reduced the activities of mitochondrial respiratory chain complexes, heightened the production of hydrogen peroxide and reactive oxygen species, and caused cellular oxidative stress and mitochondrial dysfunction. These results suggest that ZEN has adverse effects on goat endometrium cells by disrupting the mitochondrial quality control system and affecting cell cycle and proliferation. Understanding the underlying molecular pathways involved in ZEN-induced mitochondrial dysfunction and its consequences on cell function will provide critical insights into the reproductive toxicity of ZEN and contribute to safeguarding the health and wellbeing of animals and humans exposed to this mycotoxin.


Asunto(s)
Proliferación Celular , Endometrio , Cabras , Mitocondrias , Zearalenona , Animales , Femenino , Endometrio/citología , Endometrio/metabolismo , Endometrio/efectos de los fármacos , Zearalenona/toxicidad , Zearalenona/farmacología , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Estrés Oxidativo/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/efectos de los fármacos , Células Cultivadas , Dinámicas Mitocondriales/efectos de los fármacos , Mitofagia/efectos de los fármacos , Células del Estroma/metabolismo , Células del Estroma/efectos de los fármacos , Células del Estroma/citología
5.
Small ; : e2311128, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38888124

RESUMEN

Intracerebral hemorrhage (ICH) is a hemorrhagic disease with high mortality and disability rates. Curcumin is a promising drug for ICH treatment due to its multiple biological activities, but its application is limited by its poor watersolubility and instability. Herein, platelet membrane-coated curcumin polylactic-co-glycolic acid (PLGA) nanoparticles (PCNPs) are prepared to achieve significantly improved solubility, stability, and sustained release of curcumin. Fourier transform infrared spectra and X-ray diffraction assays indicate good encapsulation of curcumin within nanoparticles. Moreover, it is revealed for the first time that curcumin-loaded nanoparticles can not only suppress hemin-induced astrocyte proliferation but also induce astrocytes into neuron-like cells in vitro. PCNPs are used to treat rat ICH by tail vein injection, using in situ administration as control. The results show that PCNPs are more effective than curcumin-PLGA nanoparticles in concentrating on hemorrhagic lesions, inhibiting inflammation, suppressing astrogliosis, promoting neurogenesis, and improving motor functions. The treatment efficacy of intravenously administered PCNPs is comparable to that of in situ administration, indicating a good targeting effect of PCNPs on the hemorrhage site. This study provides a potent treatment for hemorrhagic injuries and a promising solution for efficient delivery of water-insoluble drugs using composite materials of macromolecules and cell membranes.

6.
Cell Immunol ; 401-402: 104840, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38880071

RESUMEN

Sepsis is characterized by an exacerbated inflammatory response, driven by the overproduction of cytokines, a phenomenon known as a cytokine storm. This condition is further compounded by the extensive infiltration of M1 macrophages and the pyroptosis of these cells, leading to immune paralysis. To counteract this, we sought to transition M1 macrophages into the M2 phenotype and safeguard them from pyroptosis. For this purpose, we employed ectodermal mesenchymal stem cells (EMSCs) sourced from the nasal mucosa to examine their impact on both macrophages and septic animal models. The co-culture protocol involving LPS-stimulated rat bone marrow macrophages and EMSCs was employed to examine the paracrine influence of EMSCs on macrophages. The intravenous administration of EMSCs was utilized to observe the enhancement in the survival rate of septic rat models and the protection of associated organs. The findings indicated that EMSCs facilitated M2 polarization of macrophages, which were stimulated by LPS, and significantly diminished levels of pro-inflammatory cytokines and NLRP3. Furthermore, EMSCs notably restored the mitochondrial membrane potential (MMP) of macrophages through paracrine action, eliminated excess reactive oxygen species (ROS), and inhibited macrophage pyroptosis. Additionally, the systemic integration of EMSCs substantially reduced injuries to multiple organs and preserved the fundamental functions of the heart, liver, and kidney in CLP rats, thereby extending their survival.

7.
Chemistry ; 30(27): e202400474, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38456559

RESUMEN

The relationship among chemical structure, physicochemical property and aggregation behavior of organic functional material is an important research topic. Here, we designed and synthesized three bis(squaraine) dyes BSQ1, BSQ2 and BSQ3 through the combination of two kinds of unsymmetrical azulenyl squaraine monomers. Their physicochemical properties were investigated in both molecular and aggregate states. Generally, BSQ1 displayed different assembly behaviors from BSQ2 and BSQ3. Upon fabrication into nanoparticles, BSQ1 tend to form J-aggregates while BSQ2 and BSQ3 tend to form H-aggregates in aqueous medium. When in the form of thin films, three bis(squaraine) dyes all adopted J-aggregation packing modes while only BSQ1 presented the most significant rearrangement of aggregate structures as well as the improvement in the carrier mobilities upon thermal annealing. Our research highlights the discrepancy of aggregation behaviors originating from the molecular structure and surrounding circumstances, providing guidance for the molecular design and functional applications of squaraines.

8.
Chem Res Toxicol ; 37(6): 957-967, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38771128

RESUMEN

Lung cancer is the main cause of cancer deaths around the world. Nitrosamine 4-(methyl nitrosamine)-1-(3-pyridyl)-1-butanone (NNK) is a tobacco-specific carcinogen of lung cancer. Abundant evidence implicates long noncoding RNAs (lncRNAs) in tumorigenesis. Yet, the effects and mechanisms of lncRNAs in NNK-induced carcinogenesis are still unclear. In this study, we discovered that NNK-induced transformed Beas-2B cells (Beas-2B-NNK) showed increased cell migration and proliferation while decreasing rates of apoptosis. RNA sequencing and differentially expressed lncRNAs analyses showed that lncRNA PSMB8-AS1 was obviously upregulated. Interestingly, silencing the lncRNA PSMB8-AS1 in Beas-2B-NNK cells reduced cell proliferation and migration and produced cell cycle arrest in the G2/M phase along with a decrease in CDK1 expression. Conclusively, our results demonstrate that lncRNA PSMB8-AS1 could promote the malignant characteristics of Beas-2B-NNK cells by regulating CDK1 and affecting the cell cycle, suggesting that it may supply a new prospective epigenetic mechanism for lung cancer.


Asunto(s)
Bronquios , Carcinógenos , Ciclo Celular , Proliferación Celular , Células Epiteliales , Nicotiana , ARN Largo no Codificante , Humanos , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/patología , Bronquios/citología , Bronquios/patología , Bronquios/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Nicotiana/efectos adversos , Ciclo Celular/efectos de los fármacos , Carcinógenos/toxicidad , Nitrosaminas/toxicidad , Línea Celular , Movimiento Celular/efectos de los fármacos
9.
FASEB J ; 37(6): e22989, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37199674

RESUMEN

Neuromedin S (NMS) is a neuroregulatory substance and has many important roles in regulating physiological functions in animal cells, while their specific functions and mechanisms in Leydig cells (LCs) of the testis remain unclear. The current study aims to investigate the role and potential mechanisms of NMS and its receptors in regulating steroidogenesis and proliferation in goat LCs. We found that NMS and its receptors were mainly expressed in LCs of goat testes at different ages (1-day-old, 3-month-old, and 9-month-old), and the highest expressions detected at age three months. NMS addition significantly enhanced the testosterone secretion, STAR, CYP11A1, 3BHSD, and CYP17A1 expressions, cell proliferation, and PCNA expression in vitro cultured goat LCs. Mechanistically, NMS addition increased G1/S cell population, the expressions of CCND1, CDK4 and CDK6, the activities of SOD2 and CAT, and enhanced the mitochondrial fusion, the production of ATP, and mitochondrial membrane potential, while inhibited cellular ROS production, and maintained a low ubiquitination level of mitochondrial proteins. Notably, these effects of NMS addition on goat LCs were suppressed by co-treatment with NMUR2 knockdown. Therefore, these data suggest that activating NMUR2 with NMS enhances testosterone production and cell proliferation in goat LCs through modulating mitochondrial morphology, function, and autophagy. These findings may provide a novel view of the regulatory mechanisms involved in male sexual maturation.


Asunto(s)
Cabras , Células Intersticiales del Testículo , Animales , Masculino , Células Intersticiales del Testículo/metabolismo , Cabras/metabolismo , Testosterona/metabolismo , Mitocondrias/metabolismo , Proliferación Celular
10.
Environ Res ; 243: 117801, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38043895

RESUMEN

The prevalence of antibiotic resistance genes (ARGs) in the environment is a quintessential One Health issue that threats both human and ecosystem health; however, the source and transmission of ARGs, especially clinically important ARGs (CLIARGs), in the environment have not yet been well studied. In the present study, shotgun metagenomic approaches were used to characterize the microbiome, resistome, and mobilome composition in human feces and six different environment sample types in South China. Overall, the resistome harbored 157 CLIARGs, with specific ARG hotspots (e.g., human feces, wastewater treatment plants, livestock manure and wastewater) excreting significantly higher abundance of CLIARGs compared with the natural environment. A redundancy analysis (RDA) was performed and revealed that the bacterial community compositions and mobile genetic elements (MGEs) explained 55.08% and 34.68% of the variations in ARG abundance, respectively, indicating that both bacterial community and MGEs are key contributors to the maintenance and dissemination of CLIARGs in the environment. The network analysis revealed non-random co-occurrence patterns between 200 bacterial genera and 147 CLIARGs, as well as between 135 MGEs and 123 CLIARGs. In addition to numerous co-shared CLIARGs among different sample types, the source tracking program based on the FEAST probabilistic model was used to estimate the relative contributions of the CLIARGs from potential sources to the natural environment. The source tracking analysis results delineated that mobilome, more than microbiome, contributed CLIARG transmission from those ARG hotspots into natural environment, and the MGEs in WWTPs seem to play the most significant role in the spread of CLIARGs to the natural environment (average contribution 32.9%-46.4%). Overall, this study demonstrated the distribution and dissemination of CLIARGs in the environment, and aimed to better inform strategies to control the spread of CLIARGs into the natural environment.


Asunto(s)
Antibacterianos , Microbiota , Humanos , Antibacterianos/farmacología , Relevancia Clínica , Genes Bacterianos , Farmacorresistencia Microbiana/genética , Bacterias/genética , Microbiota/genética , Secuencias Repetitivas Esparcidas
11.
BMC Urol ; 24(1): 120, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38858665

RESUMEN

Renal cell carcinoma, a leading cause of death in urological malignancies, arises from the nephron. Its characteristics include diversity in disease biology, varied clinical behaviors, different prognoses, and diverse responses to systemic therapies. The term 'organoids' is used to describe structures resembling tissues created through the three-dimensional cultivation of stem cells in vitro. These organoids, when derived from tumor tissues, can retain the diversity of the primary tumor, mirror its spatial tissue structure, and replicate similar organ-like functions. In contrast to conventional two-dimensional cell cultures and the transplantation of tumor tissues into other organisms, organoids derived from tumors maintain the complexity and microenvironment of the original tumor tissue. This fidelity makes them a more reliable model for the development of cancer drugs, potentially accelerating the translation of these drugs to clinical use and facilitating personalized treatment options for patients. This review aims to summarize the recent advancements in the use of organoids for studying renal cell carcinoma, focusing on their cultivation, potential applications, and inherent limitations.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Organoides , Organoides/patología , Humanos , Carcinoma de Células Renales/patología , Neoplasias Renales/patología , Investigación Biomédica
12.
Nano Lett ; 23(16): 7665-7674, 2023 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-37535903

RESUMEN

Precise manipulation of cancer cell death by harnessing reactive oxygen species (ROS) is a promising strategy to defeat malignant tumors. However, it is quite difficult to produce active ROS with spatial precision and regulate their biological outcomes. We succeed here in selectively generating short-lived and lipid-reactive hydroxyl radicals (•OH) adjacent to cancer cell membranes, successively eliciting lipid peroxidation and ferroptosis. DiFc-K-pY, a phosphorylated self-assembling precursor that consists of two branched Fc moieties and interacts specifically with epidermal growth factor receptor, can in situ produce membrane-bound nanofibers and enrich ferrocene moieties on cancer cell membranes in response to alkaline phosphatase. Within the acidic tumor microenvironment, DiFc-K-pY nanofibers efficiently convert tumoral H2O2 to active •OH around the target cell membranes via Fenton-like reactions, leading to lipid peroxidation and ferroptosis with good cellular selectivity. Our strategy successfully prevents tumor progression with acceptable biocompatibility through intratumoral administration.


Asunto(s)
Nanofibras , Neoplasias , Humanos , Especies Reactivas de Oxígeno/metabolismo , Metalocenos , Peróxido de Hidrógeno/metabolismo , Muerte Celular , Neoplasias/terapia , Oxidación-Reducción , Línea Celular Tumoral , Microambiente Tumoral
13.
Entropy (Basel) ; 26(5)2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38785637

RESUMEN

Spatiotemporal information on individual trajectories in urban rail transit is important for operational strategy adjustment, personalized recommendation, and emergency command decision-making. However, due to the lack of journey observations, it is difficult to accurately infer unknown information from trajectories based only on AFC and AVL data. To address the problem, this paper proposes a spatiotemporal probabilistic graphical model based on adaptive expectation maximization attention (STPGM-AEMA) to achieve the reconstruction of individual trajectories. The approach consists of three steps: first, the potential train alternative set and the egress time alternative set of individuals are obtained through data mining and combinatorial enumeration. Then, global and local potential variables are introduced to construct a spatiotemporal probabilistic graphical model, provide the inference process for unknown events, and state information about individual trajectories. Further, considering the effect of missing data, an attention mechanism-enhanced expectation-maximization algorithm is proposed to achieve maximum likelihood estimation of individual trajectories. Finally, typical datasets of origin-destination pairs and actual individual trajectory tracking data are used to validate the effectiveness of the proposed method. The results show that the STPGM-AEMA method is more than 95% accurate in recovering missing information in the observed data, which is at least 15% more accurate than the traditional methods (i.e., PTAM-MLE and MPTAM-EM).

14.
Stroke ; 54(5): 1377-1389, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37021569

RESUMEN

BACKGROUND: Neuroinflammation plays extremely crucial roles in the neurological damage mediated by ischemic stroke. TRIM29 (tripartite motif containing 29) has previously been proposed to contribute to the regulation of innate immunity, however, the effect of TRIM29 on ischemic stroke induced neurodegenerative processes and neuroinflammation still largely unexplored. In the current article, we aimed to investigate the function and the precise mechanisms of TRIM29 in ischemic stroke. METHODS: Middle cerebral artery occlusion mice model and oxygen-glucose deprivation cell model were established as in vivo and in vitro models of ischemic stroke. Quantitative real-time polymerase chain reaction (PCR), Western blot, and ELSIA were used to detect the expression levels of TRIM29, cytokines, and marker proteins. Immunofluorescence assay was performed to examine the extent of cell death. Different truncations were generated, and coimmunoprecipitation assays were used to confirm the protein interaction. Ubiquitination assay was performed to detect the ubiquitination levels. RESULTS: We found that the cerebral ischemia-reperfusion induced injury was aggravated in TRIM29 knockout mice after middle cerebral artery occlusion operation as well as the increased neurological deficits score. TRIM29 expression was also found to be up-regulated upon middle cerebral artery occlusion or OGD administration, and loss of TRIM29 promoted the apoptosis and pyroptosis of neurons and microglial cells induced by middle cerebral artery occlusion or OGD, consistent with the enhanced proinflammatory mediators production and activation of NLRC4 (NLR [NOD-like receptor] family CARD [caspase recruitment domain] domain containing protein 4) inflammasome. Furthermore, we observed that TRIM29 interacted with NLRC4 directly and promoted the K48-linked polyubiquitination of NLRC4, lead to the proteasomal degradation of NLRC4. CONCLUSIONS: In conclusion, for the first time, we revealed the role of TRIM29 in ischemic stroke and illustrated the direct relationship between TRIM29 and NLRC4.


Asunto(s)
Lesiones Encefálicas , Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Daño por Reperfusión , Animales , Ratones , Dominio de Reclutamiento y Activación de Caspasas , Infarto de la Arteria Cerebral Media , Inflamasomas/metabolismo , Microglía/metabolismo , Enfermedades Neuroinflamatorias , Daño por Reperfusión/metabolismo
15.
Small ; 19(49): e2304303, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37566779

RESUMEN

Single-atom Fe catalysts are considered as the promising catalysts for oxygen reduction reaction (ORR). However, the high electronegativity of the symmetrical coordination N atoms around Fe site generally results in too strong adsorption of *OOH intermediates on the active site, severely limiting the catalytic performance. Herein, a "heteroatom pair synergetic modulation" strategy is proposed to tailor the coordination environment and spin state of Fe sites, enabling breaking the shackles of unsuitable adsorption of intermediate products on the active centers toward a more efficient ORR pathway. The unsymmetrically Co and B heteroatomic coordinated Fe single sites supported on an N-doped carbon (Fe─B─Co/NC) catalyst perform excellent ORR activity with high half-wave potential (E1/2 ) of 0.891 V and a large kinetic current density (Jk ) of 60.6 mA cm-2 , which is several times better than those of commercial Pt/C catalysts. By virtue of in situ electrochemical impedance and synchrotron infrared spectroscopy, it is observed that the optimized Fe sites can effectively accelerate the evolution of O2 into the *O intermediate, overcoming the sluggish O─O bond cleavage of the *OOH intermediate, which is responsible for fast four-electron reaction kinetics.

16.
J Magn Reson Imaging ; 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38100518

RESUMEN

BACKGROUND: Extracellular free water (FW) resulting from white matter degeneration limits the sensitivity of diffusion tensor imaging (DTI) in predicting Alzheimer's disease (AD). PURPOSE: To evaluate the sensitivity of FW-DTI in detecting white matter microstructural changes in AD. To validate the effectiveness of FW-DTI indices to predict amyloid-beta (Aß) positivity in mild cognitive impairment (MCI) subtypes. STUDY TYPE: Retrospective. POPULATION: Thirty-eight Aß-negative cognitively healthy (CH) controls (68.74 ± 8.28 years old, 55% female), 15 Aß-negative MCI patients (MCI-n) (68.87 ± 8.83 years old, 60% female), 29 Aß-positive MCI patients (MCI-p) (73.03 ± 7.05 years old, 52% female), and 29 Aß-positive AD patients (72.93 ± 9.11 years old, 55% female). FIELD STRENGTH/SEQUENCE: 3.0T; DTI, T1 -weighted, T2 -weighted, T2 star-weighted angiography, and Aß PET (18 F-florbetaben or 11 C-PIB). ASSESSMENT: FW-corrected and standard diffusion indices were analyzed using trace-based spatial statistics. Area under the curve (AUC) in distinguishing MCI subtypes were compared using support vector machine (SVM). STATISTICAL TESTS: Chi-squared test, one-way analysis of covariance, general linear regression analyses, nonparametric permutation tests, partial Pearson's correlation, receiver operating characteristic curve analysis, and linear SVM. A P value <0.05 was considered statistically significant. RESULTS: Compared with CH/MCI-n/MCI-p, AD showed significant change in tissue compartment indices of FW-DTI. No difference was found in the FW index among pair-wise group comparisons (the minimum FWE-corrected P = 0.114). There was a significant association between FW-DTI indices and memory and visuospatial function. The SVM classifier with tissue radial diffusivity as an input feature had the best classification performance of MCI subtypes (AUC = 0.91), and the classifying accuracy of FW-DTI was all over 89.89%. DATA CONCLUSION: FW-DTI indices prove to be potential biomarkers of AD. The classification of MCI subtypes based on SVM and FW-DTI indices has good accuracy and could help early diagnosis. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 2.

17.
Analyst ; 148(3): 690-699, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36632708

RESUMEN

DNA molecular machines are widely used in the fields of biosensors and biological detection. Among them, DNA walkers have attracted much attention due to their simple design and controllability. Herein, we attempt to develop a DNA walker triggered exponential amplification method and explore its application. The AuNP probes in the DNA walker are constructed by a freezing technology, instead of the time-consuming and complex synthesis process of the traditional method. Meanwhile, after the "recognition-cleavage-relative motion" cycle of this DNA walker reaction, the exponential amplification reaction is initiated, and leads to the fluorescence recovery of the molecular beacon. Taking ricin as a target, this new method shows a limit of detection of 2.25 pM by selecting aptamers with strong binding affinity, and exhibits a wide detection range, satisfactory specificity, and excellent stability in practical application. Therefore, our method provides a universal sensing platform and has great prospects in the fields of biosensors, food safety detection, and clinical diagnostics.


Asunto(s)
Técnicas Biosensibles , Ricina , Congelación , Técnicas de Amplificación de Ácido Nucleico/métodos , ADN/química , Técnicas Biosensibles/métodos , Límite de Detección , Sondas de ADN/química
18.
Anal Bioanal Chem ; 415(8): 1411-1420, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36759390

RESUMEN

Arginine methylation is involved in many important biological processes. PRMT1 is a major arginine methyltransferase in mammalian cells and is highly conserved in eukaryotes. It catalyzes the methylation of various of substrates, including histones, and PRMT1 has been reported to be overexpressed in many cancers, indicating that it is a potential therapeutic target. No tool for efficient methylation level detection in living cells has been available to date. In this work, we designed and constructed a gene-encoded fluorescence resonance energy transfer (FRET) fluorescent sensor for detecting dimethylation levels in living cells and evaluated its functional efficiency both in vitro and in living cells. Both site-directed mutagenesis and PRMT1 inhibition experiments verified that the fluorescent sensor responded to changes in PRMT1 activity and to different PRMT1-induced methylation levels in vitro. Finally, we verified that this optimized methyl sensor responded sensitively to changes in methylation levels in living cells by overexpressing and inhibiting PRMT1, which makes it a useful tool for real-time imaging of arginine methylation. As a new tool for detecting arginine dimethylation levels in living cells, the designed FRET sensor is very important for posttranslational studies and may show a wide range of applications.


Asunto(s)
Transferencia Resonante de Energía de Fluorescencia , Histonas , Animales , Histonas/metabolismo , Proteína-Arginina N-Metiltransferasas/genética , Proteína-Arginina N-Metiltransferasas/metabolismo , Procesamiento Proteico-Postraduccional , Metilación , Arginina/metabolismo , Mamíferos/metabolismo
19.
Artículo en Inglés | MEDLINE | ID: mdl-38062310

RESUMEN

PURPOSE: Complete and rapid recanalization of blood flow by percutaneous coronary intervention (PCI) is the most effective intervention for patients with ST-segment elevation myocardial infarction (STEMI). However, myocardial ischemia/reperfusion (I/R) injury leads to microvascular obstruction (MVO), limiting its efficacy. Colchicine can reduce myocardial I/R injury, but its effect on MVO is unclear. Hence, this study aimed to assess the role and mechanism of colchicine on MVO. METHODS: Clinical data on STEMI patients with PCI were collected and risk factors related to MVO were analyzed. The rat myocardial I/R model was established to evaluate the MVO by thioflavin S staining. The myocardial I/R model of mice was treated with PBS or colchicine at the reperfusion. The effect of colchicine on cardiomyocyte apoptosis after I/R was evaluated by TUNEL and expression of cleaved caspase-3. ROS levels were detected in H9c2 cells to evaluate the colchicine effect on myocardial oxidative stress. Moreover, the mechanism through which colchicine attenuated MVO was examined using flow cytometry, WB, ELISA, immunohistochemistry, bioinformatics analysis, and immunofluorescence. RESULTS: Multivariate analysis showed that elevated neutrophils were associated with extensive MVO. Colchicine could attenuate MVO and reduce neutrophil recruitment and NETs formation after myocardial I/R. In addition, colchicine inhibited cardiomyocyte apoptosis in vivo and ROS levels in vitro. Furthermore, colchicine inhibited neutrophil proliferation in the bone marrow (BM) by inhibiting the S100A8/A9 inflammatory signaling pathway. CONCLUSIONS: Colchicine attenuated MVO after myocardial I/R injury by inhibiting the proliferation of neutrophils in BM through the neutrophil-derived S100A8/A9 inflammatory signaling pathway.

20.
Neuroradiology ; 65(3): 629-635, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36287224

RESUMEN

PURPOSE: Contrast-induced encephalopathy (CIE) was defined as new onset of neurological deficits after exposure to contrast media, which could be observed after the endovascular treatment for intracranial aneurysms. METHODS: We enrolled a consecutive cohort of patients who underwent endovascular treatment for unruptured intracranial aneurysms. CIE was defined as a reversible neuropathic syndrome that occurred after interventional therapy, accompanied by imaging abnormalities and excluding other diseases. Multivariable Poisson regression analysis was performed to show risk factors by incidence rate ratio (IRR) and a clinical strategy was proposed. RESULTS: Among the 579 patients who underwent interventional therapy for intracranial aneurysms, the crude incidence rate of CIE was 2.4% (95% CI, 1.2-3.6%) at our center. Headache, hemiplegia, and disorientation could be initial symptoms, and cortical blindness was the most common localized deficit. Cerebral edema and sulci effacement on CT were observed, and re-revaluation after treatments on CT/MRI showed absent lesions. The risk factors were history of stroke (IRR, 7.752; P = 0.007), history of hypertension (IRR, 1.064; P = 0.042), posterior circulation aneurysms (IRR, 9.412; P = 0.004) and higher dosage of contrast agents (IRR, 1.018; P = 0.007). After the strategy of accelerating excretion of contrast agents, reduction of intracranial pressure and anti-inflammation/vasospasm therapy, the prognosis was favorable with most patients fully recovered within 72 h. CONCLUSION: History of stroke and posterior circulation aneurysms were main risk factors for CIE. A higher dosage of contrast agents might induce CIE, and the history of hypertension should be considered as well.


Asunto(s)
Embolización Terapéutica , Hipertensión , Aneurisma Intracraneal , Accidente Cerebrovascular , Humanos , Aneurisma Intracraneal/terapia , Medios de Contraste , Embolización Terapéutica/métodos , Resultado del Tratamiento , Factores de Riesgo , Accidente Cerebrovascular/etiología , Hipertensión/complicaciones , Estudios Retrospectivos
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