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1.
J Am Chem Soc ; 146(1): 263-273, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38109718

RESUMEN

Dual-atom catalysts (DACs) with paired active sites can provide unique intrinsic properties for heterogeneous catalysis, but the synergy of the active centers remains to be elucidated. Here, we develop a high-performance DAC with Zn1Co1 species anchored on nitrogen-doped carbon (Zn1Co1/NC) as the dominant active site for the propane dehydrogenation (PDH) reaction. It exhibits several times higher turnover frequency (TOF) of C3H8 conversion and enhanced C3H6 selectivity compared to Zn1/NC or Co1/NC with only a single-atom site. Various experimental and theoretical studies suggest that the enhanced PDH performance stems from the promoted activation of the C-H bond of C3H8 triggered by the electronic interaction between Zn1 and Co1 colligated by N species. Moreover, the dynamic sinking of the Zn1 site and rising of the Co1 site, together with the steric effect of the dissociated H species at the bridged N during the PDH reaction, provides a feasible channel for C3H6 desorption through the more exposed Co1 site, thereby boosting the selectivity. This work provides a promising strategy for designing robust hetero DACs to simultaneously increase activity and selectivity in the PDH reaction.

2.
Curr Issues Mol Biol ; 46(5): 3906-3918, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38785510

RESUMEN

The high recurrence rate of cervical cancer is a leading cause of cancer deaths in women. 5-Fluorouracil (5-FU) is an antitumor drug used to treat many types of cancer, but its diminishing effectiveness and side effects limit its use. Norcantharidin (NCTD), a demethylated derivative of cantharidin, exhibits various biological activities. Here, we investigated whether NCTD could potentiate 5-FU to induce cervical cancer cell death. To assess the cell viability and synergistic effects of the drugs, cell counting kit-8 and colony formation assays were performed using HR-HPV-positive cervical cancer cell lines. Annexin V-FITC/PI staining and TUNEL assays were performed to confirm the induction of apoptosis. The synergistic effect of NCTD on the antitumor activity of 5-FU was analyzed using network pharmacology, molecular docking, and molecular dynamics simulations. Apoptosis-related proteins were examined using immunoblotting. The combination of NCTD and 5-FU was synergistic in cervical cancer cell lines. Network pharmacological analysis identified 10 common targets of NCTD and 5-FU for cervical cancer treatment. Molecular docking showed the strong binding affinity of both compounds with CA12, CASP9, and PTGS1. Molecular dynamics simulations showed that the complex system of both drugs with caspase-9 could be in a stable state. NCTD enhanced 5-FU-mediated cytotoxicity by activating apoptosis-related proteins. NCTD acts synergistically with 5-FU to inhibit cervical cancer cell proliferation. NCTD enhances 5-FU-induced apoptosis in cervical cancer cell lines via the caspase-dependent pathway.

3.
Biochem Biophys Res Commun ; 714: 149976, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38677007

RESUMEN

BACKGROUND: The systemic treatment of advanced hepatocellular carcinoma is currently facing a bottleneck. EGCG, the primary active compound in green tea, exhibits anti-tumor effects through various pathways. However, there is a lack of study on EGCG-induced immunogenic cell death (ICD) in hepatocellular carcinoma. METHODS: In a previous study, we successfully synthesized folate-modified thermosensitive nano-materials, encapsulated EGCG within nanoparticles using a hydration method, and established the EGCG nano-drug delivery system. The viability of HepG2 cells post-EGCG treatment was assessed via the MTT and EdU assays. Cell migration and invasion were evaluated through wound healing experiments, Transwell assays, and Annexin V-FITC/PI assay for apoptosis detection. Additionally, the expression levels of damage-associated molecular patterns (DAMPs) were determined using immunofluorescence, ATP measurement, RT-qPCR, and Western Blot. RESULTS: The drug sensitivity test revealed an IC50 value of 96.94 µg/mL for EGCG in HepG2 cells after 48 h. EGCG at a low concentration (50 µg/mL) significantly impeded the migration and invasion of HepG2 cells, showing a clear dose-dependent response. Moreover, medium to high EGCG concentrations induced cell apoptosis in a dose-dependent manner and upregulated DAMPs expression. Immunofluorescence analysis demonstrated a notable increase in CRT expression following low-concentration EGCG treatment. As EGCG concentration increased, cell viability decreased, leading to CRT exposure on the cell membrane. EGCG also notably elevated ATP levels. RT-qPCR and Western Blot analyses indicated elevated expression levels of HGMB1, HSP70, and HSP90 following EGCG intervention. CONCLUSION: EGCG not only hinders the proliferation, migration, and invasion of hepatocellular carcinoma cells and induces apoptosis, but also holds significant clinical promise in the treatment of malignant tumors by promoting ICD and DAMPs secretion.


Asunto(s)
Carcinoma Hepatocelular , Catequina , Catequina/análogos & derivados , Ácido Fólico , Neoplasias Hepáticas , Humanos , Catequina/farmacología , Catequina/química , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Células Hep G2 , Ácido Fólico/química , Ácido Fólico/farmacología , Movimiento Celular/efectos de los fármacos , Muerte Celular Inmunogénica/efectos de los fármacos , Nanosferas/química , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Temperatura , Calreticulina/metabolismo
4.
Biochem Biophys Res Commun ; 720: 150079, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-38759300

RESUMEN

Stroke and major depression disorder are common neurological diseases, and a large number of clinical studies have shown that there is a close relationship between the two diseases, but whether the two diseases are linked at the genetic level needs to be further explored. The purpose of this study was to explore the comorbidity mechanism of stroke and major depression by using bioinformatics technology and animal experiments. From the GEO database, we gathered transcriptome data of stroke and depression mice (GSE104036, GSE131712, GSE81672, and GSE146845) and identified comorbid gene set through edgR and WGCNA analyses. Further analysis revealed that these genes were enriched in pathways associated with cell death. Programmed cell death gene sets (PCDGs) are generated from genes related to apoptosis, necroptosis, pyroptosis and autophagy. The intersection of PCDGs and comorbid gene set resulted in two hub genes, Mlkl and Nlrp3. Single-cell sequencing analysis indicated that Mlkl and Nlrp3 are mainly influential on endothelial cells and microglia, suggesting that the impairment of these two cell types may be a factor in the relationship between stroke and major depression. This was experimentally confirmed by RT-PCR and immunofluorescence staining. Our research revealed that two specific genes, namely, Mlkl and Nlrp3, play crucial roles in the complex mechanism that links stroke and major depression. Additionally, we have predicted six possible therapeutic agents and the outcomes of docking simulations of target proteins and drug molecules.


Asunto(s)
Trastorno Depresivo Mayor , Accidente Cerebrovascular , Animales , Trastorno Depresivo Mayor/genética , Trastorno Depresivo Mayor/metabolismo , Accidente Cerebrovascular/genética , Accidente Cerebrovascular/metabolismo , Ratones , Ratones Endogámicos C57BL , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Masculino , Transcriptoma , Biología Computacional/métodos , Apoptosis/genética
5.
Small ; 20(14): e2306983, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37988639

RESUMEN

Constructing S-scheme heterojunction catalysts is a key challenge in visible-light catalysed degradation of organic pollutants. Most heterojunction materials are reported to face significant obstacles in the separation of photogenerated electron-hole pairs owing to differences in the material size and energy barriers. In this study, sulfur-doped g-C3N4 oxidative-type semiconductor materials are synthesized and then coupled with BiOBr reductive-type semiconductor to form S-g-C3N4/BiOBr S-scheme heterojunction. A strong and efficient internal electric field is established between the two materials, facilitating the separation of photogenerated electron-hole pairs. Notably, in situ XPS proved that after visible light irradiation, Bi3+ is converted into Bi(3+ɑ)+, and a large number of photogenerated holes are produced on the surface of BiOBr, which oxidized and activated H2O into •OH.  â€¢OH cooperated with •O2 - and 1O2 to attack Rhodamine B (RhB) molecules to achieve deep oxidation mineralization. The composite material is designed with a LUMO energy level higher than that of RhB, promoting the sensitization of RhB by injecting photogenerated electrons into the heterojunction, thereby enhancing the photocatalytic performance to 22.44 times that of pure g-C3N4. This study provides a new perspective on the efficient degradation of organic molecules using visible light catalysis.

6.
Small ; 20(27): e2311076, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38279579

RESUMEN

Developing active, stable, and cost-efficient electrocatalysts to replace platinum for the alkaline hydrogen evolution reaction (HER) is highly desirable yet represents a great challenge. Here, it is reported on a facile one-pot synthesis of RuxNi layered double hydroxides (RuxNi-LDHs) that exhibit remarkable HER activity and stability after an in-situ activation treatment, surpassing most state-of-the-art Ru-based catalysts as well as commercial Ru/C and Pt/C catalysts. The structural and chemical changes triggered by in-situ activation are systematically investigated, and the results clearly show that the pristine, less-active RuxNi-LDHs are transformed into a highly active catalyst characterized by raft-like, defect-rich Ru° particles decorated on the surface of RuxNi-LDHs. Density functional theory (DFT) calculations reveal that the defective Ru sites can effectively optimize the reaction pathway and lower the free energies of the elemental steps involved, leading to enhanced intrinsic activity. This work highlights the importance of the currently understudied strategy of defect engineering in boosting the HER activity of Ru-based catalysts and offers an effective approach involving in-situ electrochemical activation for the development of high-performance alkaline HER catalysts.

7.
Plant Physiol ; 192(3): 2301-2317, 2023 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-36861636

RESUMEN

Heat stress has a deleterious effect on male fertility in rice (Oryza sativa), but mechanisms to protect against heat stress in rice male gametophytes are poorly understood. Here, we have isolated and characterized a heat-sensitive male-sterile rice mutant, heat shock protein60-3b (oshsp60-3b), that shows normal fertility at optimal temperatures but decreasing fertility as temperatures increase. High temperatures interfered with pollen starch granule formation and reactive oxygen species (ROS) scavenging in oshsp60-3b anthers, leading to cell death and pollen abortion. In line with the mutant phenotypes, OsHSP60-3B was rapidly upregulated in response to heat shock and its protein products were localized to the plastid. Critically, overexpression of OsHSP60-3B enhanced the heat tolerance of pollen in transgenic plants. We demonstrated that OsHSP60-3B interacted with FLOURY ENDOSPERM6(FLO6) in plastids, a key component involved in the starch granule formation in the rice pollen. Western blot results showed that FLO6 level was substantially decreased in oshsp60-3b anthers at high temperature, indicating that OsHSP60-3B is required to stabilize FLO6 when temperatures exceed optimal conditions. We suggest that in response to high temperature, OsHSP60-3B interacts with FLO6 to regulate starch granule biogenesis in rice pollen and attenuates ROS levels in anthers to ensure normal male gametophyte development in rice.


Asunto(s)
Respuesta al Choque Térmico , Oryza , Almidón , Temperatura , Fertilidad/genética , Respuesta al Choque Térmico/genética , Oryza/metabolismo , Plastidios/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Almidón/metabolismo
8.
Phys Rev Lett ; 132(15): 153801, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38683010

RESUMEN

In this Letter, we explore the intersection of chirality and recently discovered toroidal spatiotemporal optical vortices (STOVs). We introduce "photonic conchs" theoretically as a new type of toroidal-like state exhibiting geometrical chirality, and experimentally observe these wave packets with controllable topological charges. Unlike toroidal STOVs, photonic conchs exhibit unique chirality-related dynamical evolution in free space and possess an orbital angular momentum correlated with all the dimensions of space-time. This research deepens our understanding of toroidal light states and potentially advances various fields by unveiling similar wave phenomena in a broader scope of physics systems, including acoustics and electronics.

9.
Chemphyschem ; 25(12): e202400083, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38511509

RESUMEN

Adsorbates on metal surfaces are typically formed from the dissociative chemisorption of molecules occurring at gas-solid interfaces. These adsorbed species exhibit unique diffusion behaviors on metal surfaces, which are influenced by their translational energy. They play crucial roles in various fields, including heterogeneous catalysis and corrosion. This review examines recent theoretical advancements in understanding the diffusion dynamics of adsorbates on metal surfaces, with a specific emphasis on hydrogen and oxygen atoms. The diffusion processes of adsorbates on metal surfaces involve two energy transfer mechanisms: surface phonons and electron-hole pair excitations. This review also surveys new theoretical methods, including the characterization of the electron-hole pair excitation within electronic friction models, the acceleration of quantum chemistry calculations through machine learning, and the treatment of atomic nuclear motion from both quantum mechanical and classical perspectives. Furthermore, this review offers valuable insights into how energy transfer, nuclear quantum effects, supercell sizes, and the topography of potential energy surfaces impact the diffusion behavior of hydrogen and oxygen species on metal surfaces. Lastly, some preliminary research proposals are presented.

10.
Protein Expr Purif ; 215: 106392, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37952787

RESUMEN

Cluster of differentiation 20 (CD20) is a nonglycosylated, multispanning transmembrane protein specifically integrated by B lymphocytes. Similar to CD20, another four-pass transmembrane protein, claudin 18.2, has attracted attention as an emerging therapeutic target for cancer. However, their poor solubility and toxic nature often hinder downstream applications, such as antibody drug development. Therefore, developing a cost-effective method for producing drug targets with multiple membrane-spanning domains is crucial. In this study, a high yield of recombinant CD20 was achieved through an E. coli-based in vitro coupled transcription-translation system. Surface plasmon resonance results showed that rituximab (an antileukemia drug) has nanomolar affinity with the CD20 protein, which aligns with published results. Notably, a previously hard-to-express claudin 18.2 recombinant protein was successfully expressed in the same reaction system by replacing its membrane-spanning domains with the transmembrane domains of CD20. The folding of the extracellular domain of the chimeric protein was verified using a commercial anti-claudin 18 antibody. This study provides a novel concept for promoting the expression of four-pass transmembrane proteins and lays the foundation for the large-scale industrial production of membrane-associated drug targets, similar to claudin 18.2.


Asunto(s)
Antígenos CD20 , Escherichia coli , Antígenos CD20/genética , Antígenos CD20/metabolismo , Escherichia coli/metabolismo , Rituximab/genética , Rituximab/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Claudinas/metabolismo
11.
Cerebrovasc Dis ; 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38253035

RESUMEN

OBJECTIVE: Aim of the present article was the demonstration of the institutional experience with the endovascular management of the anterior inferior cerebellar artery (AICA) aneurysms in order to propose a treatment algorithm. METHODS: Clinical data were obtained from 33 patients with 37 AICA aneurysms who had been surgically treated at the authors' hospital between 2010 and 2022. The patients' medical records, imaging data, and follow-up outcomes were retrospectively analyzed. RESULTS: All 33 patients (10 males, 23 females; mean age 54.88±12.49 years) underwent endovascular therapy for AICA aneurysms. The most common chief complaints were headache (87.9%), nausea and vomiting (57.6%), and alteration of consciousness (27.3%). 31 patients experienced subarachnoid hemorrhage (SAH). Regarding the AICA aneurysm location, 23 aneurysms were found at the right side of AICA in DSA images, and there were 6, 9, 16, 6 aneurysms in segments A1-A4, respectively. Coiling (59.5%), Onyx embolization (29.7%), coiling-combined Onyx embolization (5.4%), non-intervention (5.4%) were chosen in the surgical strategy. The length of follow-up was 8.09±5.05 months, and 84.8% of the patients had favorable modified Rankin Scale (mRS) scores. The complete occlusion rates were 94.6%. Postoperative complications occurred in 4 cases (12.1 %), including new neurological deficit in 3 cases and cerebral infarction in 1 case. 1 patient died after follow-up because of the severe pneumonia. Poor initial Hunt and Hess grade (HHG) (p=0.007) was the risk factor for unfavorable clinical outcome. The rupture status (p=0.025) and the location (p=0.021) of the AICA aneurysms are statistically significant in determining which operation strategy to be chosen. Coiling had an advantage over Onyx embolization (P=0.001) in parent artery preservation (PAP). CONCLUSIONS: In this study, an algorithm for the treatment of AICA aneurysms was proposed based on the clinical status of the patients before treatment, the anatomical factors of AICA and the technical conditions of EVT. To our knowledge, this is the first study to report more than 30 cases of AICA aneurysms that had been treated by EVT and to advocate a treatment algorithm. EVT of AICA aneurysms is an optional strategy, but decisions are made based on the specific condition, anatomical location and other factors.

12.
Phys Chem Chem Phys ; 26(10): 8494-8503, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38411205

RESUMEN

Single-atom catalysts (SACs) are emerging as promising candidates for electrochemical nitrogen reduction reaction (NRR). Previous studies have shown that the single-atom centers of SACs can not only serve as active sites, but also act as promoters to affect the catalytic properties. However, the use of single metal atoms as promoters in electrocatalysis has rarely been studied. In this work, the defective Keggin-type phosphomolybdic acid (PMA) is used as a substrate to support the single metal atoms. We aim to tune the electronic structures of the exposed molybdenum active sites on defective PMA by using these supported single atoms as promoters for efficient NRR. Firstly, the stability and N2 adsorption capacity were studied to screen for an effective catalyst capable of activating N2. Most of the SACs were found to have good stability and N2 adsorption capacity. Then, we compared the selectivity and NRR activity of the catalysts and found that catalysts with metal atom promoters have improved NRR selectivity and activity. Finally, electronic structure analysis was carried out to understand the promoting effect of the promoter on N2 activation and the activity of the NRR process. This work provides a new strategy for designing efficient catalysts for electrocatalytic reactions by introducing promoters.

13.
BMC Anesthesiol ; 24(1): 108, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38515077

RESUMEN

BACKGROUND: High lactate to albumin ratio (LAR) has been reported to be associated to with poor prognosis in patients admitted to the intensive care unit (ICU). However, its role in predicting in-hospital mortality in AF patients admitted to ICU has not been explored. METHODS: The Medical Information Mart for Intensive Care-IV (MIMIC-IV) database was used to retrieve information on patients who had been diagnosed with AF. X-tile software was utilized to determine the optimal cut-off LAR. Area under the receiver operating characteristic curves (AUC), calibration plots, and decision curve analysis (DCA) were conducted to assess the prediction performance of LAR for in-hospital mortality. RESULTS: Finally, 8,287 AF patients were included and 1,543 death (18.6%) occurred. The optimal cut-off value of LAR is 0.5. Patients in lower LAR (< 0.5) group showed a better in-hospital survival compared to patients in higher LAR (≥ 0.5) group (HR: 2.67, 95%CI:2.39-2.97, P < 0.001). A nomogram for in-hospital mortality in patients with AF was constructed based on multivariate Cox analysis including age, CCI, ß blockers usage, APSIII, hemoglobin and LAR. This nomogram exhibited excellent discrimination and calibration abilities in predicting in-hospital mortality for critically ill AF patients. CONCLUSION: LAR, as a readily available biomarker, can predict in-hospital mortality in AF patients admitted to the ICU. The nomogram that combined LAR with other relevant variables performed exceptionally well in terms of predicting in-hospital mortality.


Asunto(s)
Fibrilación Atrial , Humanos , Fibrilación Atrial/diagnóstico , Ácido Láctico , Mortalidad Hospitalaria , Estudios Retrospectivos , Cuidados Críticos , Unidades de Cuidados Intensivos , Albúminas
14.
Reprod Domest Anim ; 59(4): e14566, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38627959

RESUMEN

Early pregnancy loss is a primary cause of low reproductive rates in dairy cows, posing severe economic losses to dairy farming. The accurate diagnosis of dairy cows with early pregnancy loss allows for oestrus synchronization, shortening day open, and increasing the overall conception rate of the herd. Several techniques are available for detecting early pregnancy loss in dairy cows, including rectal ultrasound, circulating blood progesterone, and pregnancy-associated glycoproteins (PAGs). Yet, there is a need to improve on existing techniques and develop novel strategies to identify cows with early pregnancy loss accurately. This manuscript reviews the applications of rectal ultrasound, circulating blood progesterone concentration, and PAGs in the diagnosis of pregnancy loss in dairy cows. The manuscript also discusses the recent progress of new technologies, including colour Doppler ultrasound (CDUS), interferon tau-induced genes (ISGs), and exosomal miRNA in diagnosing pregnancy loss in dairy cows. This study will provide an option for producers to re-breed cows with pregnancy loss, thereby reducing the calving interval and economic costs. Meanwhile, this manuscript might also act as a reference for exploring more economical and precise diagnostic technologies for early pregnancy loss in dairy cows.


Asunto(s)
Enfermedades de los Bovinos , Progesterona , Embarazo , Femenino , Bovinos , Animales , Aborto Veterinario/diagnóstico , Reproducción , Fertilización , Glicoproteínas , Inseminación Artificial/veterinaria , Enfermedades de los Bovinos/diagnóstico
15.
Environ Toxicol ; 39(5): 2893-2907, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38299319

RESUMEN

BACKGROUND: N6-Methyladenosine (m6A) RNA methylation modulators are implicated in nasopharyngeal carcinoma (NPC). Circular RNAs (circRNAs) stimulate/inhibit the development of NPC by sponging microRNAs (miRNAs). Herein, m6A modifications affecting the circRNA/miRNA axis in NPC were explored. METHODS: Twenty prognostic m6A RNA methylation regulators were identified from 504 head/neck squamous cell carcinoma and 44 normal samples from The Cancer Genome Atlas (TCGA). Differentially expressed miRNAs were screened from the TCGA and Gene Expression Omnibus (GEO) databases. RNA-binding protein (RBP)-circRNA and circRNA-miRNA interactive pairs were verified using RBPmap and RNAhybrid, respectively. The RBP/circRNA/miRNA network was constructed using Cytoscape. Furthermore, CircITCH (hsa_circ_00059948), HNRNPC, and miR-224-3p expressions were detected by western blotting and quantitative polymerase chain reaction. The role of circITCH in NPC was examined using apoptosis, scratch wound healing, transwell invasion, and cell counting kit-8 assays. Finally, CircITCH-miR-224-3p and circITCH-HNRNPC interactions were assessed by dual-luciferase reporter and RNA-immunoprecipitation (RIP) assays, respectively. RESULTS: Bioinformatics analysis revealed that high pathological grade, late-stage tumors, and low survival were associated with increased HNRNPC expression. MiR-224-3p was upregulated in NPC and sequestered by circITCH. Construction of the RBP/circRNA/miRNA network highlighted the HNRNPC/circITCH/miR-224-3p axis. In vitro experiments demonstrated decreased circITCH expression and increased HNRNPC and miR-224-3p expressions in NPC. In NPC cells overexpressing circITCH, HNRNPC and miR-224-3p expressions were significantly decreased. Dual-luciferase assays demonstrated a targeting relationship between circITCH and miR-224-3p, and RIP assays demonstrated interaction of HNRNPC targets with circITCH. CONCLUSION: CircITCH overexpression inhibited NPC progression by sequestering miR-224-3p, and HNRNPC reduced circITCH expression through direct interaction.


Asunto(s)
MicroARNs , Neoplasias Nasofaríngeas , Humanos , Regulación hacia Abajo/genética , Carcinoma Nasofaríngeo/genética , ARN Circular/genética , Carcinogénesis/genética , Transformación Celular Neoplásica , Luciferasas , MicroARNs/genética , Línea Celular Tumoral , Proliferación Celular , Ribonucleoproteína Heterogénea-Nuclear Grupo C/genética
16.
Molecules ; 29(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38731520

RESUMEN

Graphitic carbon nitride (g-C3N4), recognized for its considerable potential as a heterogeneous photocatalyst in water splitting, has attracted extensive research interest. By using density functional theory (DFT) calculations, the regulatory role of p-block metal (PM) single atoms on the photocatalytic activity of g-C3N4 in overall water splitting was systematically explored. The incorporation of PM atoms (Ge, Sn and Pb) led to a reduction in the overpotentials required for both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER). Combined with the electronic structures analysis via hybrid functional, it was found that the introduction of Ge, Sn or Pb optimizes the positions of the valence band maximum (VBM) and the conduction band minimum (CBM), providing a robust driving force for HER and ensuring substantial driving force for OER. Meanwhile, the presence of these three PMs induces the spatial separation of VBM and CBM, inhibiting the recombination of carriers. These findings have significant implications for the design and preparation of efficient photocatalysts.

17.
Angew Chem Int Ed Engl ; : e202405371, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38965044

RESUMEN

Spillover of adsorbed species from one active site to another is a key step in heterogeneous catalysis. However, the factors controlling this step, particularly the spillover of polyatomic species, have rarely been studied. Herein, we investigate the spillover dynamics of H* and CH3* species on a single-atom alloy surface (Rh/Cu(111)) upon the dissociative chemisorption of methane (CH4), using molecular dynamics that considers both surface phonons and electron-hole pairs. These dynamical calculations are made possible by a high-dimensional potential energy surface machine learned from density functional theory data. Our results provide compelling evidence that the H* and CH3* can spill over on the metal surface at experimental temperatures and reveal novel dynamical features involving an internal motion during diffusion for CH3*. Increasing surface temperature has minor effect on promoting spillover, as geminate recombinative desorption becomes more prevalent. However, the poisoning of the active site can be mitigated by frequent gaseous molecular collisions that occur under ambient pressure in real-world catalysis, which transfer energy to the trapped adsorbates. Interestingly, the bulky CH3* exhibits a significant spillover advantage over the light H* due to its larger size, which facilitates energy acquisition. These insights help to advance our understanding of spillover in heterogeneous catalysis.

18.
J Am Chem Soc ; 145(24): 13169-13180, 2023 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-37279334

RESUMEN

Direct selective oxidation of methane (DSOM) to high value-added oxygenates under mild conditions is attracting considerable interest. Although state-of-the-art supported metal catalysts can improve methane conversion, it is still challenging to avoid the deep oxidation of oxygenates. Here, we develop a highly efficient metal-organic frameworks (MOFs)-supported single-atom Ru catalyst (Ru1/UiO-66) for the DSOM reaction using H2O2 as an oxidant. It endows nearly 100% selectivity and an excellent turnover frequency of 185.4 h-1 for the production of oxygenates. The yield of oxygenates is an order of magnitude higher than that on UiO-66 alone and several times higher than that on supported Ru nanoparticles or other conventional Ru1 catalysts, which show severe CO2 formation. Detailed characterizations and density functional theory calculations reveal a synergistic effect between the electron-deficient Ru1 site and the electron-rich Zr-oxo nodes of UiO-66 on Ru1/UiO-66. The Ru1 site is responsible for the activation of CH4 via the resulting Ru1═O* species, while the Zr-oxo nodes undertake the formation of oxygenic radical species to produce oxygenates. In particular, the Zr-oxo nodes retrofitted by Ru1 can prune the excess H2O2 to inactive O2 more than •OH species, helping to suppress the over-oxidation of oxygenates.

19.
Theor Appl Genet ; 136(5): 121, 2023 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-37119337

RESUMEN

KEY MESSAGE: The use of multi-environment trials to test yield-related traits in a diverse alfalfa panel allowed to find multiple molecular markers associated with complex agronomic traits. Yield is one of the most important target traits in alfalfa breeding; however, yield is a complex trait affected by genetic and environmental factors. In this study, we used multi-environment trials to test yield-related traits in a diverse panel composed of 200 alfalfa accessions and varieties. Phenotypic data of maturity stage measured as mean stage by count (MSC), dry matter content, plant height (PH), biomass yield (Yi), and fall dormancy (FD) were collected in three locations in Idaho, Oregon, and Washington from 2018 to 2020. Single-trial and stagewise analyses were used to obtain estimated trait means of entries by environment. The plants were genotyped using a genotyping by sequencing approach and obtained a genotypic matrix with 97,345 single nucleotide polymorphisms. Genome-wide association studies identified a total of 84 markers associated with the traits analyzed. Of those, 29 markers were in noncoding regions and 55 markers were in coding regions. Ten significant SNPs at the same locus were associated with FD and they were linked to a gene annotated as a nuclear fusion defective 4-like (NFD4). Additional SNPs associated with MSC, PH, and Yi were annotated as transcription factors such as Cysteine3Histidine (C3H), Hap3/NF-YB family, and serine/threonine-protein phosphatase 7 proteins, respectively. Our results provide insight into the genetic factors that influence alfalfa maturity, yield, and dormancy, which is helpful to speed up the genetic gain toward alfalfa yield improvement.


Asunto(s)
Estudio de Asociación del Genoma Completo , Medicago sativa , Medicago sativa/genética , Sitios de Carácter Cuantitativo , Fitomejoramiento , Fenotipo , Polimorfismo de Nucleótido Simple
20.
Chemphyschem ; 24(11): e202200937, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36849705

RESUMEN

Carbon neutrality has drawn increasing attention for realizing the carbon cyclization and reducing the greenhouse effect. Although the C1 products, such as CO, can be achieved with a high Faraday efficiency, the targeted production of C2 fuels as well as the mechanism have not been systematically investigated. In this work, we carry out a first-principles study to screen dual-atom catalysts (DACs) for producing C2 fuels through the electrocatalytic carbon monoxide reduction reaction (e-CORR). We find that methanol, ethanol and ethylene can be produced on both DAC-Co and DAC-Cu, while acetate can be achieved on DAC-Cu only. Importantly, methanol and ethylene are preferred on DAC-Co, while acetate and ethylene on DAC-Cu. Furthermore, we show that the explicit solvent can enhance the adsorption and influence the protonation steps, which subsequently affects the protonation and dimerization behavior as well as the performance and selectivity of e-CORR on DACs. We further demonstrate that the C-C coupling is easy to be formed and stabilized if the Integrated Crystal Orbital Hamilton Population (ICOHP) is low because of the low energy barrier. Our findings provide not only guidance on the design of novel catalysts for e-CORR, but an insightful understanding on the reduction mechanism.

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