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1.
Angew Chem Int Ed Engl ; : e202409079, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38874984

RESUMEN

Despite the widespread investigations on the M-N-C type single atom catalysts (SACs) for oxygen evolution reaction (OER), an internal conflict between its intrinsic thermodynamically structural instability and apparent catalytic steadiness has long been ignored. Clearly unfolding this contradiction is necessary and meaningful for understanding the real structure-property relation of SACs. Herein, by using the well-designed pH-dependent metal leaching experiments and X-ray absorption spectroscopy, an unconventional structure reconstruction of M-N-C catalyst during OER process was observed. Combining with density functional theory calculations, the initial Ni-N coordination is easily broken in the presence of adsorbed OH*, leading to favorable formation of Ni-O coordination. The formed Ni-O works stably as the real active center for OER catalysis in alkaline media but unstably in acid, which clearly explains the existing conflict. Unveiling the internal contradiction between structural instability and catalytic steadiness provides valuable insights for rational design of single atom OER catalysts.

2.
Angew Chem Int Ed Engl ; : e202405637, 2024 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-38825570

RESUMEN

Directly coupling N2 and CO2 to synthesize urea by photocatalysis paves a sustainable route for urea synthesis, but its performance is limited by the competition of photogenerated electrons between N2 and CO2, as well as the underutilized photogenerated holes. Herein, we report an efficient urea synthesis process involving photogenerated electrons and holes in respectively converting CO2 and N2 over a redox heterojunction consisting of WO3 and Ni single-atom-decorated CdS (Ni1-CdS/WO3). For the photocatalytic urea synthesis from N2 and CO2 in pure water, Ni1-CdS/WO3 attained a urea yield rate of 78 µM·h-1 and an apparent quantum yield of 0.15 % at 385 nm, which ranked among the best photocatalytic urea synthesis performance reported. Mechanistic studies reveal that the N2 was converted into NO species by ⋅OH radicals generated from photogenerated holes over the WO3 component, meanwhile, the CO2 was transformed into *CO species over the Ni site by photogenerated electrons. The generated NO and *CO species were further coupled to form *OCNO intermediate, then gradually transformed into urea. This work emphasizes the importance of reasonably utilizing photogenerated holes in photocatalytic reduction reactions.

3.
Environ Sci Technol ; 58(21): 9436-9445, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38691809

RESUMEN

Although electro-Fenton (EF) processes can avoid the safety risks raised by concentrated hydrogen peroxide (H2O2), the Fe(III) reduction has always been either unstable or inefficient at high pH, resulting in catalyst deactivation and low selectivity of H2O2 activation for producing hydroxyl radicals (•OH). Herein, we provided a strategy to regulate the surface dipole moment of TiO2 by Fe anchoring (TiO2-Fe), which, in turn, substantially increased the H2O2 activation for •OH production. The TiO2-Fe catalyst could work at pH 4-10 and maintained considerable degradation efficiency for 10 cycles. Spectroscopic analysis and a theoretical study showed that the less polar Fe-O bond on TiO2-Fe could finely tune the polarity of H2O2 to alter its empty orbital distribution, contributing to better ciprofloxacin degradation activity within a broad pH range. We further verified the critical role of the weakened polarity of H2O2 on its homolysis into •OH by theoretically and experimentally investigating Cu-, Co-, Ni-, Mn-, and Mo-anchored TiO2. This concept offers an avenue for elaborate design of green, robust, and pH-universal cathodic Fenton-like catalysts and beyond.


Asunto(s)
Peróxido de Hidrógeno , Titanio , Peróxido de Hidrógeno/química , Concentración de Iones de Hidrógeno , Titanio/química , Hierro/química , Radical Hidroxilo/química , Catálisis , Electrodos
4.
Adv Mater ; : e2404213, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38695334

RESUMEN

Developing efficient and robust electrocatalysts toward the oxygen evolution reaction (OER) is critical for proton exchange membrane water electrolysis (PEMWE). RuO2 possesses intrinsically high OER activity, but the concurrent electrochemical dissolution leads to rapid deactivation. Here a unique RuO2 catalyst containing metallic Ru─Ru interactions (m-RuO2) is reported, which maintains stability in practical PEMWE for 100 h at 60 °C and 1 A cm-2. Experimental and theoretical investigations suggest that the presence of Ru─Ru interactions significantly increases the energy barrier for the formation of RuO2(OH)2, which is a key intermediate for Ru dissolution, and hence substantially mitigates the electrochemical corrosion of m-RuO2. Meanwhile, the Ru4d band center downshifts, accordingly, ensuring the high OER activity, and the participation of lattice oxygen in the OER is also suppressed at the Ru─Ru sites, further contributing to the enhanced durability. Interestingly, such enhanced stability is also dependent on the size of metallic Ru─Ru cluster, where the energy barrier is further increased for Ru3, but is decreased for Ru5. These results highlight the significance of local coordination structure modulation on the electrochemical stability of RuO2 and open a feasible avenue toward the development of robust OER electrocatalysts for high-performance PEMWE.

5.
Nat Commun ; 15(1): 3233, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622140

RESUMEN

Electrochemical hydrogenation of acetonitrile based on well-developed proton exchange membrane electrolyzers holds great promise for practical production of ethylamine. However, the local acidic condition of proton exchange membrane results in severe competitive proton reduction reaction and poor selection toward acetonitrile hydrogenation. Herein, we conduct a systematic study to screen various metallic catalysts and discover Pd/C exhibits a 43.8% ethylamine Faradaic efficiency at the current density of 200 mA cm-2 with a specific production rate of 2912.5 mmol g-1 h-1, which is about an order of magnitude higher than the other screened metal catalysts. Operando characterizations indicate the in-situ formed PdHx is the active centers for catalytic reaction and the adsorption strength of the *MeCH2NH2 intermediate dictates the catalytic selectivity. More importantly, the theoretical analysis reveals a classic d-band mediated volcano curve to describe the relation between the electronic structures of catalysts and activity, which could provide valuable insights for designing more effective catalysts for electrochemical hydrogenation reactions and beyond.

6.
Nat Commun ; 15(1): 3231, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622167

RESUMEN

Engineering atom-scale sites are crucial to the mitigation of polysulfide shuttle, promotion of sulfur redox, and regulation of lithium deposition in lithium-sulfur batteries. Herein, a homonuclear copper dual-atom catalyst with a proximal distance of 3.5 Å is developed for lithium-sulfur batteries, wherein two adjacent copper atoms are linked by a pair of symmetrical chlorine bridge bonds. Benefiting from the proximal copper atoms and their unique coordination, the copper dual-atom catalyst with the increased active interface concentration synchronously guide the evolutions of sulfur and lithium species. Such a delicate design breaks through the activity limitation of mononuclear metal center and represents a catalyst concept for lithium-sulfur battery realm. Therefore, a remarkable areal capacity of 7.8 mA h cm-2 is achieved under the scenario of sulfur content of 60 wt.%, mass loading of 7.7 mg cm-2 and electrolyte dosage of 4.8 µL mg-1.

7.
Adv Mater ; 36(26): e2312369, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38581648

RESUMEN

Traditional noble metal oxide, such as RuO2, is considered a benchmark catalyst for acidic oxygen evolution reaction (OER). However, its practical application is limited due to sluggish activity and severe electrochemical corrosion. In this study, Ru-Fe nanoparticles loading on carbon felt (RuFe@CF) is synthesized via an ultrafast Joule heating method as an active and durable OER catalyst in acidic conditions. Remarkably low overpotentials of 188 and 269 mV are achieved at 10 and 100 mA cm-2, respectively, with a robust stability up to 620 h at 10 mA cm-2. When used as an anode in a proton exchange membrane water electrolyzer, the catalyst shows more than 250 h of stability at a water-splitting current of 200 mA cm-2. Experimental characterizations reveal the presence of a Ru-based oxide nanosheath on the surface of the catalyst during OER tests, suggesting a surface reconstruction process that enhances the intrinsic activity and inhibits continuous metal dissolution. Moreover, density functional theory calculations demonstrate that the introduction of Fe into the RuFe@CF catalyst reduces the energy barrier and boosts its activities. This work offers an effective and universal strategy for the development of highly efficient and stable catalysts for acidic water splitting.

8.
Clin Transl Med ; 14(4): e1650, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38649772

RESUMEN

BACKGROUND: Although many molecules have been investigated as biomarkers for spinal cord injury (SCI) or ischemic stroke, none of them are specifically induced in central nervous system (CNS) neurons following injuries with low baseline expression. However, neuronal injury constitutes a major pathology associated with SCI or stroke and strongly correlates with neurological outcomes. Biomarkers characterized by low baseline expression and specific induction in neurons post-injury are likely to better correlate with injury severity and recovery, demonstrating higher sensitivity and specificity for CNS injuries compared to non-neuronal markers or pan-neuronal markers with constitutive expressions. METHODS: In animal studies, young adult wildtype and global Atf3 knockout mice underwent unilateral cervical 5 (C5) SCI or permanent distal middle cerebral artery occlusion (pMCAO). Gene expression was assessed using RNA-sequencing and qRT-PCR, while protein expression was detected through immunostaining. Serum ATF3 levels in animal models and clinical human samples were measured using commercially available enzyme-linked immune-sorbent assay (ELISA) kits. RESULTS: Activating transcription factor 3 (ATF3), a molecular marker for injured dorsal root ganglion sensory neurons in the peripheral nervous system, was not expressed in spinal cord or cortex of naïve mice but was induced specifically in neurons of the spinal cord or cortex within 1 day after SCI or ischemic stroke, respectively. Additionally, ATF3 protein levels in mouse blood significantly increased 1 day after SCI or ischemic stroke. Importantly, ATF3 protein levels in human serum were elevated in clinical patients within 24 hours after SCI or ischemic stroke. Moreover, Atf3 knockout mice, compared to the wildtype mice, exhibited worse neurological outcomes and larger damage regions after SCI or ischemic stroke, indicating that ATF3 has a neuroprotective function. CONCLUSIONS: ATF3 is an easily measurable, neuron-specific biomarker for clinical SCI and ischemic stroke, with neuroprotective properties. HIGHLIGHTS: ATF3 was induced specifically in neurons of the spinal cord or cortex within 1 day after SCI or ischemic stroke, respectively. Serum ATF3 protein levels are elevated in clinical patients within 24 hours after SCI or ischemic stroke. ATF3 exhibits neuroprotective properties, as evidenced by the worse neurological outcomes and larger damage regions observed in Atf3 knockout mice compared to wildtype mice following SCI or ischemic stroke.


Asunto(s)
Factor de Transcripción Activador 3 , Biomarcadores , Accidente Cerebrovascular Isquémico , Neuronas , Traumatismos de la Médula Espinal , Animales , Femenino , Humanos , Masculino , Ratones , Factor de Transcripción Activador 3/metabolismo , Factor de Transcripción Activador 3/genética , Biomarcadores/metabolismo , Biomarcadores/sangre , Modelos Animales de Enfermedad , Accidente Cerebrovascular Isquémico/metabolismo , Accidente Cerebrovascular Isquémico/genética , Accidente Cerebrovascular Isquémico/sangre , Ratones Noqueados , Neuronas/metabolismo , Traumatismos de la Médula Espinal/metabolismo , Traumatismos de la Médula Espinal/genética , Traumatismos de la Médula Espinal/complicaciones
9.
Bioact Mater ; 36: 238-255, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38481566

RESUMEN

Apoptosis has long been recognized as a significant mechanism for inhibiting tumor formation, and a plethora of stimuli can induce apoptosis during the progression and treatment of tumors. Moreover, tumor-derived apoptotic extracellular vesicles (apoEVs) are inevitably phagocytosed by live tumor cells, promoting tumor heterogeneity. Understanding the mechanism by which apoEVs regulate tumor cells is imperative for enhancing our knowledge of tumor metastasis and recurrence. Herein, we conducted a series of in vivo and in vitro experiments, and we report that tumor-derived apoEVs promoted lung adenocarcinoma (LUAD) metastasis, self-renewal and chemoresistance. Mechanistically, we demonstrated that apoEVs facilitated tumor metastasis and stemness by initiating the epithelial-mesenchymal transition program and upregulating the transcription of the stem cell factor SOX2. In addition, we found that ALDH1A1, which was transported by apoEVs, activated the NF-κB signaling pathway by increasing aldehyde dehydrogenase enzyme activity in recipient tumor cells. Furthermore, targeting apoEVs-ALDH1A1 significantly abrogated these effects. Collectively, our findings elucidate a novel mechanism of apoEV-dependent intercellular communication between apoptotic tumor cells and live tumor cells that promotes the formation of cancer stem cell-like populations, and these findings reveal that apoEVs-ALDH1A1 may be a potential therapeutic target and biomarker for LUAD metastasis and recurrence.

10.
ACS Nano ; 18(14): 10312-10323, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38533779

RESUMEN

Defect engineering is essential for the development of efficient electrocatalysts at the atomic level. While most work has focused on various vacancies as effective catalytic modulators, little attention has been paid to the relation between the local atomic environment of vacancies and catalytic activities. To face this challenge, we report a facile synthetic approach to manipulate the local atomic environments of vacancies in MoS2 with tunable Mo-to-S ratios. Our studies indicate that the MoS2 with more Mo terminated vacancies exhibits better hydrogen evolution reaction (HER) performance than MoS2 with S terminated vacancies and defect-free MoS2. The improved performance originates from the adjustable orbital orientation and distribution, which is beneficial for regulating H adsorption and eventually boosting the intrinsic per-site activity. This work uncovers the underlying essence of the local atomic environment of vacancies on catalysis and provides a significant extension of defect engineering for the rational design of transition metal dichalcogenides (TMDs) catalysts and beyond.

11.
Sci Bull (Beijing) ; 69(8): 1081-1090, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38395652

RESUMEN

Maximally exploiting the active sites of iridium catalysts is essential for building low-cost proton exchange membrane (PEM) electrolyzers for green H2 production. Herein, we report a novel microdrop-confined fusion/blasting (MCFB) strategy for fabricating porous hollow IrO1-x microspheres (IrO1-x-PHM) by introducing explosive gas mediators from a NaNO3/glucose mixture. Moreover, the developed MCFB strategy is demonstrated to be general for synthesizing a series of Ir-based composites, including Ir-Cu, Ir-Ru, Ir-Pt, Ir-Rh, Ir-Pd, and Ir-Cu-Pd and other noble metals such as Rh, Ru, and Pt. The hollow structures can be regulated using different organics with NaNO3. The assembled PEM electrolyzer with IrO1-x-PHM as the anode catalyst (0.5 mg/cm2) displays an impressive polarization voltage of 1.593 and 1.726 V at current densities of 1 and 2A/cm2, respectively, outperforming commercial IrOx catalysts and most of the ever-reported iridium catalysts with such low catalyst loading. More importantly, the breakdown of the polarization loss indicates that the improved performance is due to the facilitated mass transport induced by the hollowness. This study offers a versatile platform for fabricating efficient Ir-based catalysts for PEM electrolyzers and beyond.

12.
Sci Bull (Beijing) ; 69(8): 1100-1108, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38423872

RESUMEN

Catalytic conversion of nitrate (NO3-) pollutants into ammonia (NH3) offers a sustainable and promising route for both wastewater treatment and NH3 synthesis. Alkali cations are prevalent in nitrate solutions, but their roles beyond charge balance in catalytic NO3- conversion have been generally ignored. Herein, we report the promotion effect of K+ cations in KNO3 solution for NO3- reduction over a TiO2-supported Ni single-atom catalyst (Ni1/TiO2). For photocatalytic NO3- reduction reaction, Ni1/TiO2 exhibited a 1.9-fold NH3 yield rate with nearly 100% selectivity in KNO3 solution relative to that in NaNO3 solution. Mechanistic studies reveal that the K+ cations from KNO3 gradually bonded with the surface of Ni1/TiO2, in situ forming a K-O-Ni moiety during reaction, whereas the Na+ ions were unable to interact with the catalyst in NaNO3 solution. The charge accumulation on the Ni sites induced by the incorporation of K atom promoted the adsorption and activation of NO3-. Furthermore, the K-O-Ni moiety facilitated the multiple proton-electron coupling of NO3- into NH3 by stabilizing the intermediates.

13.
Nat Commun ; 15(1): 1614, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38388525

RESUMEN

While Ru owns superior catalytic activity toward hydrogen oxidation reaction and cost advantages, the catalyst deactivation under high anodic potential range severely limits its potential to replace the Pt benchmark catalyst. Unveiling the deactivation mechanism of Ru and correspondingly developing protection strategies remain a great challenge. Herein, we develop atomic Pt-functioned Ru nanoparticles with excellent anti-deactivation feature and meanwhile employ advanced operando characterization tools to probe the underlying roles of Pt in the anti-deactivation. Our studies reveal the introduced Pt single atoms effectively prevent Ru from oxidative passivation and consequently preserve the interfacial water network for the critical H* oxidative release during catalysis. Clearly understanding the deactivation nature of Ru and Pt-induced anti-deactivation under atomic levels could provide valuable insights for rationally designing stable Ru-based catalysts for hydrogen oxidation reaction and beyond.

14.
Chem Commun (Camb) ; 59(94): 14013-14016, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37942830

RESUMEN

The high unoccupied d band energy of FeS2 basically results in weak orbital coupling with water molecules, consequently leading to sluggish water dissociation kinetics. Herein, we demonstrate that the N-induced doping effect and phase transition engineering (FeS2 to N-Fe7S8) can downshift the unoccupied d orbitals and strengthen the interfacial orbital coupling to boost the water dissociation kinetics. The fabricated N-Fe7S8/carbon cloth (CC) displays superb hydrogen evolution reaction performance with a low overpotential (89 mV at 10 mA cm-2) and small Tafel slope (105 mV dec-1) under alkaline conditions. It is revealed that the electronic structure of Fe is modulated by N doping and phase transition. The downshifted d band energy can strengthen water adsorption and reduce the energy barrier of water dissociation. Our work provides a new strategy to modify metal sulfide electrocatalysts for electrochemical energy conversion.

15.
Mar Drugs ; 21(11)2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37999388

RESUMEN

Alginate oligosaccharides prepared by alginate lyases attracted great attention because of their desirable biological activities. However, the hydrolysis products are always a mixture of oligosaccharides with different degrees of polymerization, which increases the production cost because of the following purification procedures. In this study, an alginate lyase, Alg4755, with high product specificity was identified, heterologously expressed, and characterized from Vibrio alginolyticus S10, which was isolated from the intestine of sea cucumber. Alg4755 belonged to the PL7 family with two catalytic domains, which was composed of 583 amino acids. Enzymatic characterization results show that the optimal reaction temperature and pH of Alg4755 were 35 °C and 8.0, respectively. Furthermore, Alg4755 was identified to have high thermal and pH stability. Moreover, the final hydrolysis products of sodium alginate catalyzed by Alg4755 were mainly alginate disaccharides with a small amount of alginate trisaccharides. The results demonstrate that alginate lyase Alg4755 could have a broad application prospect because of its high product specificity and desirable catalytic properties.


Asunto(s)
Disacáridos , Vibrio alginolyticus , Vibrio alginolyticus/genética , Vibrio alginolyticus/metabolismo , Proteínas Bacterianas/metabolismo , Concentración de Iones de Hidrógeno , Especificidad por Sustrato , Oligosacáridos/metabolismo , Polisacárido Liasas/metabolismo , Alginatos/metabolismo
16.
J Neuroinflammation ; 20(1): 227, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37798730

RESUMEN

BACKGROUND: Some patients show persistent cognitive decline for weeks, months or even years after surgery, which seriously affects their long-term prognosis and quality of life. However, most previous basic studies have focused mainly on the mechanisms of early postoperative cognitive decline, whereas cognitive decline in the longer term after surgery is less well-understood. The subgranular zone of the dentate gyrus exhibits life-long neurogenesis, supporting hippocampus-dependent learning and memory. MAIN TEXT: The aim of this study was to investigate whether adult hippocampal neurogenesis (AHN) involves in cognitive decline later following surgery and to further explore the roles of CD8 + T lymphocytes infiltrating the hippocampal parenchyma after surgery in this pathological process. Cognitive function was examined in adult mice that underwent laparotomy combined with partial hepatectomy, and the results showed that cognitive decline persisted in mice who underwent surgery during the first postoperative month, even though there was a trend toward continuous improvement over time. Significantly decreased numbers of DCX + cells, BrdU + cells, and BrdU + /DCX + cells were observed on day 8 after surgery, and a significantly decreased number of NeuN + /BrdU + cells was observed on day 28 after surgery, which indicated inhibition of AHN. After surgery, T lymphocytes, the majority of which were CD8 + T cells, infiltrated the hippocampus and secreted Interferon-γ (IFN-γ). Depletion of CD8 + T cells could inhibit the increase of IFN-γ synthesis, improve hippocampal neurogenesis, and improve postoperative cognitive function. Hippocampal microinjection of IFN-γ neutralizing antibody or adeno-associated virus to knock down IFN-γ receptor 1 (IFNGR1) could also partially attenuate the inhibition of AHN and improve postoperative cognitive function. CONCLUSIONS: These results demonstrate that postoperative infiltration of CD8 + T cells into the hippocampus and subsequent secretion of IFN-γ contribute to the inhibition of AHN and cognitive decline later following surgery.


Asunto(s)
Disfunción Cognitiva , Calidad de Vida , Ratones , Humanos , Animales , Adulto , Bromodesoxiuridina , Hipocampo/patología , Neurogénesis/fisiología , Disfunción Cognitiva/etiología , Disfunción Cognitiva/patología , Interferón gamma , Linfocitos T CD8-positivos
17.
FASEB J ; 37(10): e23164, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37688590

RESUMEN

Postoperative cognitive decline (POCD) is a common and serious complication following anesthesia and surgery; however, the precise mechanisms of POCD remain unclear. Our previous research showed that sevoflurane impairs adult hippocampal neurogenesis (AHN) and thus cognitive function in the aged brain by affecting neurotrophin-3 (NT-3) expression; however, the signaling mechanism involved remains unexplored. In this study, we found a dramatic decrease in the proportion of differentiated neurons with increasing concentrations of sevoflurane, and the inhibition of neural stem cell differentiation was partially reversed after the administration of exogenous NT-3. Understanding the molecular underpinnings by which sevoflurane affects NT-3 is key to counteracting cognitive dysfunction. Here, we report that sevoflurane administration for 2 days resulted in upregulation of histone deacetylase 9 (HDAC9) expression, which led to transcriptional inactivation of cAMP-response element binding protein (CREB). Due to the colocalization of HDAC9 and CREB within cells, this may be related to the interaction between HDAC9 and CREB. Anyway, this ultimately led to reduced NT-3 expression and inhibition of neural stem cell differentiation. Furthermore, knockdown of HDAC9 rescued the transcriptional activation of CREB after sevoflurane exposure, while reversing the downregulation of NT-3 expression and inhibition of neural stem cell differentiation. In summary, this study identifies a unique mechanism by which sevoflurane can inhibit CREB transcription through HDAC9, and this process reduces NT-3 levels and ultimately inhibits neuronal differentiation. This finding may reveal a new strategy to prevent sevoflurane-induced neuronal dysfunction.


Asunto(s)
Fenómenos Fisiológicos del Sistema Nervioso , Neuronas , Adulto , Humanos , Anciano , Sevoflurano/farmacología , Diferenciación Celular , Proteína de Unión a Elemento de Respuesta al AMP Cíclico , Elementos de Respuesta
18.
Thorac Cancer ; 14(23): 2275-2287, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37424293

RESUMEN

BACKGROUND: Serine protease inhibitors clade B serpins (SERPINBs) are the largest subclass of protease inhibitors, once thought of as a tumor suppressor gene family. However, some SERPINBs exhibit functions unrelated to the inhibition of catalytic activity. METHODS: The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), Gene Set Cancer Analysis (GSCA), and cBioPortal databases were utilized to investigate SERPINBs expression, prognostic correlation, and genomic variation in 33 cancer types. We also conducted a comprehensive transcriptome analysis in multiple lung adenocarcinoma (LUAD) cohorts to reveal the molecular mechanism of SERPINB5 in LUAD. Then, qPCR and immunohistochemistry were used to verify the expression and prognostic value of SERPINB5 in LUAD patients. Furthermore, knockdown and overexpression of SERPINB5 in LUAD cell lines were performed to evaluate cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT). RESULTS: The expression of SERPINB5 was upregulated and demethylated in LUAD, and its abnormally high expression was significantly correlated with poor overall survival (OS). In addition, the expression of SERPINB5 was analyzed to determine its prognostic value in LUAD and confirmed that SERPINB5 was an independent predictor of LUAD in TCGA and GEO cohorts and qPCR validation with 106 clinical samples. At last, A knockdown of SERPINB5 in LUAD cells reduced proliferation, migration, and EMT. Proliferation, migration, and invasion are promoted by the overexpression of SERPINB5. CONCLUSION: Therefore, SERPINB5 has shown potential as a prognostic biomarker for LUAD, and it may become a potential therapeutic target for lung adenocarcinoma.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Serpinas , Humanos , Serpinas/genética , Transición Epitelial-Mesenquimal , Pronóstico , Adenocarcinoma del Pulmón/genética , Proliferación Celular , Neoplasias Pulmonares/genética , Biomarcadores
19.
Mar Drugs ; 21(7)2023 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-37504926

RESUMEN

The study aimed to investigate the effects of alcalase, papain, flavourzyme, and neutrase on the structural characteristics and bioactivity stability of Cucumaria frondosa intestines and ovum hydrolysates (CFHs). The findings revealed that flavourzyme exhibited the highest hydrolysis rate (51.88% ± 1.87%). At pH 2.0, the solubility of hydrolysate was the lowest across all treatments, while the solubility at other pH levels was over 60%. The primary structures of hydrolysates of different proteases were similar, whereas the surface hydrophobicity of hydrolysates was influenced by the types of proteases used. The hydrolysates produced by different proteases were also analyzed for their absorption peaks and antioxidant activity. The hydrolysates of flavourzyme had ß-fold absorption peaks (1637 cm-1), while the neutrase and papain hydrolysates had N-H bending vibrations. The tertiary structure of CFHs was unfolded by different proteases, exposing the aromatic amino acids and red-shifting of the λ-peak of the hydrolysate. The alcalase hydrolysates showed better antioxidant activity in vitro and better surface hydrophobicity than the other hydrolysates. The flavourzyme hydrolysates displayed excellent antioxidant stability and pancreatic lipase inhibitory activity during gastrointestinal digestion, indicating their potential use as antioxidants in the food and pharmaceutical industries.


Asunto(s)
Cucumaria , Péptido Hidrolasas , Animales , Péptido Hidrolasas/metabolismo , Papaína/química , Antioxidantes/farmacología , Hidrólisis , Intestinos , Subtilisinas/química , Hidrolisados de Proteína/química
20.
Nat Commun ; 14(1): 3847, 2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37386000

RESUMEN

Copper is well-known to be selective to primary amines via electrocatalytic nitriles hydrogenation. However, the correlation between the local fine structure and catalytic selectivity is still illusive. Herein, we find that residual lattice oxygen in oxide-derived Cu nanowires (OD-Cu NWs) plays vital roles in boosting the acetonitrile electroreduction efficiency. Especially at high current densities of more than 1.0 A cm-2, OD-Cu NWs exhibit relatively high Faradic efficiency. Meanwhile, a series of advanced in situ characterizations and theoretical calculations uncover that oxygen residues, in the form of Cu4-O configuration, act as electron acceptors to confine the free electron flow on the Cu surface, consequently improving the kinetics of nitriles hydrogenation catalysis. This work could provide new opportunities to further improve the hydrogenation performance of nitriles and beyond, by employing lattice oxygen-mediated electron tuning engineering.


Asunto(s)
Cobre , Electrones , Hidrogenación , Acetonitrilos , Nitrilos , Catálisis , Óxidos , Oxígeno
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