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1.
Mol Cell Biochem ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38740701

RESUMEN

Pulmonary arterial hypertension (PAH) is a pathophysiological syndrome that is extremely difficult to manage, and there is currently no effective treatment. We want to elucidate the therapeutic effect of ethyl pyruvate (EP) on PAH and its possible mechanism. Pulmonary artery endothelial cells (PAECs) were cultured in conventional low-oxygen environments, and cellular proliferation was monitored after treatment with EP. Expression of p-PI3K/Akt, LC3-II, and Beclin-1 was detected by Western blot. After hyperkinetic PAH rabbits' models were treated with EP, hemodynamic data were collected. Right ventricular hypertrophy and pulmonary vascular remodeling were evaluated. Expression of p-PI3K/Akt, LC3-II, and Beclin-1 protein was also detected after using autophagy inhibitor and agonists. We found that EP could inhibit PAECs proliferation. After EP treatment, expression of p-PI3K/Akt was upregulated in vitro and in vivo. LC3-II and Beclin-1 were inhibited and their expression was lower after autophagy inhibitor was given, while after administration of autophagy agonists, their expression was higher than that in the EP alone group. Besides, EP attenuated PAH, and right ventricular hypertrophy and pulmonary vascular remodeling were also reversed. EP can reduce PAH and reverse vascular remodeling which is associated with inhibition of autophagy in PAECs based on PI3K-Akt signaling pathway. The results of this study can provide surgical opportunities for patients with severe PAH caused by congenital heart disease in clinical cardiovascular surgery.

2.
Inorg Chem ; 63(37): 17316-17328, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39221825

RESUMEN

Developing low-cost and multifunctional adsorbents for adsorption separation to obtain high-purity (>99.9%) gases is intriguing yet challenging. Notably, the ongoing trade-off between adsorption capacity and selectivity in separating multicomponent mixed gases still persists as a pressing scientific challenge requiring urgent attention. Herein, the ultrastable TJT-100 exhibits unique structural characteristics including uncoordinated carboxylate oxygen atoms, coordinated water molecules directed toward the pore surface, and sufficient Me2NH2+ cations in channels. TJT-100 exhibits a high adsorption capacity and exceptional separation performance, particularly notable for its high C2H2 capacity of 127.7 cm3/g and remarkable C2H2 selectivity over CO2 (5.4) and CH4 (19.8), which makes it a standout material for various separation applications. In a breakthrough experiment with a C2H2/CO2 mixture (v/v = 50/50), TJT-100 achieved a record-high C2H2 productivity of 69.33 L/kg with a purity of 99.9%. Additionally, TJT-100 demonstrates its effectiveness in separating CO2 from natural gas and flue gas. Its exceptional selectivity for CO2/CH4 (10.7) and CO2/N2 (11.9) results in a high CO2 productivity of 21.23 and 22.93 L/kg with 99.9% purity from CO2/CH4 (v/v = 50/50) and CO2/N2 (v/v = 15/85) mixtures, respectively.

3.
Inorg Chem ; 63(36): 16897-16907, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39197012

RESUMEN

Exploiting a photocatalyst with high stability and excellent activity for Cr(VI) reduction under mild conditions is crucial yet challenging. Herein, the rigid aromatic multicarboxylate ligand with chromophore anthracene was selected to coordinate with multivalent metal ion manganese and to obtain a stable two-dimensional (2D) Mn-based metal-organic framework (MOF), LCUH-120, which can efficiently and quickly convert Cr(VI) into Cr(III) under light without the need for any additional photosensitizer. The efficient photosensitive anthracene group serves as a photosensitizer center and multivalent Mn(II) ion as a photocatalyst center in LCUH-120, and the conversion of Cr(VI) to Cr(III) can be realized completely in just 40 min. Specifically, the rate constant (k) and reduction rate of the Cr(VI) photocatalytic reaction can be high up to 0.134 min-1 and 2.50 mgCr(VI) g-1cata min-1 in an acidic environment (pH = 2), respectively. Compared to our previously reported three-dimensional (3D) Sm-MOF, LCUH-120 exhibits a significantly higher catalytic reaction rate, which might be ascribed to the fact that the photocatalyst center Mn node can improve the rate of electron transfer and promote the separation of holes and photogenerated electrons. In an acidic environment, the reaction mechanism can be verified through various contrast experiments and theoretical simulations.

4.
Heart Lung Circ ; 33(2): 251-259, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38307791

RESUMEN

AIM: Hyperkinetic pulmonary arterial hypertension (PAH) is a complication of congenital heart disease. Gene therapy is a new experimental treatment for PAH, and ultrasound-mediated gene-carrying microbubble targeted delivery is a promising development for gene transfer. METHODS: This study successfully established a hyperkinetic PAH rabbit model by a common carotid artery and jugular vein shunt using the cuff style method. Liposome microbubbles carrying the hepatocyte growth factor (HGF) gene were successfully constructed. An in vitro experiment evaluated the appropriate intensity of ultrasonic radiation by Western blots and 3H-TdR incorporation assays. In an in vivo experiment, after transfection of ultrasound-mediated HGF gene microbubbles, catheterisation was applied to collect haemodynamic data. Hypertrophy of the right ventricle was evaluated by measuring the right ventricle hypertrophy index. Western blot and immunohistochemistry analyses were used to detect the expression of human (h)HGF and angiogenic effects, respectively. RESULTS: The most appropriate ultrasonic radiation intensity was 1.0 W/cm2 for 5 minutes. Two weeks after transfection, both systolic pulmonary arterial pressure and mean pulmonary arterial pressure were attenuated. Hypertrophy of the right ventricle was reversed. hHGF was transplanted into the rabbits, resulting in a high expression of hHGF protein and an increase in the number of small pulmonary arteries. Ultrasound-mediated HGF gene microbubble therapy was more effective at attenuating PAH and increasing the density of small pulmonary arteries than single HGF plasmid transfection. CONCLUSIONS: Ultrasound-mediated HGF gene microbubbles significantly improved the target of gene therapy in a rabbit PAH model and enhanced the tropism and transfection rates. Thus, the technique can effectively promote small pulmonary angiogenesis and play a role in the treatment of PAH without adverse reactions.


Asunto(s)
Hipertensión Pulmonar , Hipertensión Arterial Pulmonar , Animales , Conejos , Humanos , Hipertensión Pulmonar/genética , Hipertensión Pulmonar/terapia , Hipertensión Pulmonar/diagnóstico , Microburbujas , Factor de Crecimiento de Hepatocito/genética , Hipertensión Pulmonar Primaria Familiar , Hipertrofia
5.
Phys Rev Lett ; 131(20): 202502, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-38039451

RESUMEN

Traditional photonuclear reactions primarily excite giant dipole resonances, making the measurement of isovector giant resonances with higher multipolarities a great challenge. In this Letter, the manipulation of collective excitations of different multipole transitions in even-even nuclei via vortex γ photons is investigated. We develop the calculation method for photonuclear cross sections induced by the vortex γ photon beam using the fully self-consistent random-phase approximation plus particle-vibration coupling (RPA+PVC) model based on Skyrme density functional. We find that the electromagnetic transitions with multipolarity J<|m_{γ}| are forbidden for vortex γ photons due to the angular momentum conservation, with m_{γ} being the projection of total angular momentum of γ photon on its propagation direction. For instance, this allows for probing the isovector giant quadrupole resonance without interference from dipole transitions using vortex γ photons with m_{γ}=2. Furthermore, the electromagnetic transition with J=|m_{γ}|+1 vanishes at a specific polar angle. Therefore, the giant resonances with specific multipolarity can be extracted via vortex γ photons. Moreover, the vortex properties of γ photons can be meticulously diagnosed by measuring the nuclear photon-absorption cross section. Our method opens new avenues for photonuclear excitations, generation of coherent γ photon laser and precise detection of vortex particles, and consequently, has significant impact on nuclear physics, nuclear astrophysics and strong laser physics.

6.
Inorg Chem ; 62(34): 13832-13846, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37591631

RESUMEN

The discharge of harmful and toxic pollutants in water is destroying the ecosystem balance and human being health at an alarming rate. Therefore, the detection and removal of water pollutants by using stable and efficient materials are significant but challenging. Herein, three novel lanthanide metal-organic frameworks (Ln-MOFs), [La(L)(DMF)2(H2O)2]·H2O (LCUH-104), [Nd(L)(DMF)2(H2O)2]·H2O (LCUH-105), and [Pr(L)(DMF)2(H2O)2]·H2O (LCUH-106) [H3L = 5-(4-(tetrazol-5-yl)phenyl)isophthalic acid (H3TZI)] were solvothermally constructed and structurally characterized. In the three Ln-MOFs, dinuclear metallic clusters {Ln2} were connected by deprotonated tetrazol-containing dicarboxylate TZI3- to obtain a 2D layered framework with a point symbol of {42·84}·{46}. Their excellent chemical and thermal stabilities were beneficial to carry out fluorescence sensing and achieve the catalytic nitrophenols (NPs) reduction. Especially, the incorporation of the nitrogen-rich tetrazole ring into their 2D layered frameworks enables the fabrication of Pd nanocatalysts (Pd NPs@LCUH-104/105/106) and have dramatically enhanced catalytic activity by using the unique metal-support interactions between three Ln-MOFs and the encapsulating palladium nanoparticles (Pd NPs). Specifically, the reduction of NPs (2-NP, 3-NP, and 4-NP) in aqueous solution by Pd NPs@LCUH-104 exhibits exceptional conversion efficiency, remarkable rate constants (k), and outstanding cycling stability. The catalytic rate of Pd NPs@LCUH-104 for 4-NP is nearly 8.5 times more than that of Pd/C (wt 5%) and its turnover frequency value is 0.051 s-1, which indicate its excellent catalytic activity. Meanwhile, LCUH-105, as a multifunctional fluorescence sensor, exhibited excellent fluorescence detection of norfloxacin (NFX) (turn on) and Cr2O72- (turn off) with high selectivity and sensitivity at a low concentration, and the corresponding fluorescence enhancement/quenching mechanism has also been systematically investigated through various detection means and theoretical calculations.

7.
Inorg Chem ; 62(14): 5757-5771, 2023 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-36966509

RESUMEN

The rational design and preparation of stable and multifunctional metal-organic frameworks (MOFs) with excellent catalysis and adsorption properties are desirable but are great challenges. The nitrophenol (NP) reduction to aminophenols (APs) by using the catalyst Pd@MOFs is an effective strategy, which has attracted extensive attention in recent years. Here, we report four stable isostructural two-dimensional (2D) rare earth metal-organic frameworks [RE4(AAPA)6(DMA)2 (H2O)4][DMA]3[H2O]8 (namely LCUH-101, RE = Eu, Gd, Tb, Y; AAPA2- = 5-[(anthracen-9-yl-methyl)-amino]-1,3-isophthalate), which feature a 2D layer structure with sql topology of point symbol {44·62} and exhibit excellent chemical stability and thermostability. The as-synthesized Pd@LCUH-101 was utilized for the catalytic reduction of 2/3/4-nitrophenol, which indicates high catalytic activity and recyclability attributed to the synergistic effect between Pd nanoparticles and the 2D layered structure. Of note, the turnover frequency (TOF), the reaction rate constant (k), and the activation energy (Ea) of Pd@LCUH-101 (Eu) in the reduction of 4-NP, respectively, are 1.09 s-1, 2.17 min-1, and 50.2 kJ·mol-1, which show that it has superior catalytic activity. Remarkably, LCUH-101 (Eu, Gd, Tb, and Y) are multifunctional MOFs that can effectively absorb and separate mixed dyes. The appropriate interlayer spacing enables them to efficiently adsorb methylene blue (MB) and rhodamine B (RhB) in aqueous solution, with adsorption capacities of 0.97 and 0.41 g·g-1, respectively, which is one of the highest values among those of the reported MOF-based adsorbers. Meanwhile, LCUH-101 (Eu) can be used for the separation of the dye mixture MB/MO and RhB/MO, and the excellent reusability enables LCUH-101 (Eu) to be used as chromatographic column filters to quickly separate and recover dyes. Therefore, this work provides a new strategy for the exploitation of stable and efficient catalysts for NP reduction and adsorbents for dyes.

8.
Inorg Chem ; 62(49): 20325-20339, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38015879

RESUMEN

The design and development of proton conduction materials for clean energy-related applications is obviously important and highly desired but challenging. An ultrastable cobalt-based metal-organic framework Co-MOF, formulated as [Co2(btzip)2(µ2-OH2)] (namely, LCUH-103, H2btzip = 4, 6-bis(triazol-1-yl)-isophthalic acid) had been successfully synthesized via the hydrothermal method. LCUH-103 exhibits a three-dimensional framework and a one-dimensional microporous channel structure with scu topology based on the binuclear metallic cluster {Co2}. LCUH-103 indicated excellent chemical and thermal stability; peculiarly, it can retain its entire framework in acid and alkali solutions with different pH values for 24 h. The excellent stability is a prerequisite for studying its proton conductivity, and its proton conductivity σ can reach up to 1.25 × 10-3 S·cm-1 at 80 °C and 100% relative humidity (RH). In order to enhance its proton conductivity, the proton-conducting material Im@LCUH-103 had been prepared by encapsulating imidazole molecules into the channels of LCUH-103. Im@LCUH-103 indicated an excellent proton conductivity of 3.18 × 10-2 S·cm-1 at 80 °C and 100% RH, which is 1 order of magnitude higher than that of original LCUH-103. The proton conduction mechanism was systematically studied by various detection means and theoretical calculations. Meanwhile, LCUH-103 is also an excellent carrier for palladium nanoparticles (Pd NPs) via a wetness impregnation strategy, and the nitrophenols (4/3/2-NP) reduction in aqueous solution by Pd@LCUH-103 indicated an outstanding conversion efficiency, high rate constant (k), and exceptional cycling stability. Specifically, the k value of 4-NP reduction by Pd@LCUH-103 is superior to many other reported catalysts, and its k value is as high as 1.34 min-1 and the cycling stability can reach up to 6 cycles. Notably, its turnover frequency (TOF) value is nearly 196.88 times more than that of Pd/C (wt 5%) in the reaction, indicating its excellent stability and catalytic activity.

9.
Heart Surg Forum ; 26(2): E156-E159, 2023 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-36972601

RESUMEN

A 37-year-old male patient with corrected transposition of great arteries (ccTGA) with cor triatriatum sinister (CTS), left superior vena cava, and atrial septal defects is reported in our case. None of these impacted the patient's growth or development, nor daily work until age 33. Later, the patient developed symptoms of obvious impaired heart function, which improved after medical treatment. However, the symptoms reappeared and gradually worsened two years later, and we decided to treat it with surgery. In this case, we selected tricuspid mechanical valve replacement, cor triatriatum correction, and atrial septal defect repair. During the follow-up of five years, the patient had no obvious symptoms, ECG did not change significantly from five years ago, and the cardiac color Doppler ultrasound showed RVEF 0.51.


Asunto(s)
Corazón Triatrial , Cardiopatías Congénitas , Defectos del Tabique Interatrial , Transposición de los Grandes Vasos , Masculino , Humanos , Adulto , Corazón Triatrial/complicaciones , Corazón Triatrial/diagnóstico , Corazón Triatrial/cirugía , Vena Cava Superior/cirugía , Defectos del Tabique Interatrial/complicaciones , Defectos del Tabique Interatrial/diagnóstico , Defectos del Tabique Interatrial/cirugía , Transposición de los Grandes Vasos/complicaciones , Transposición de los Grandes Vasos/diagnóstico , Transposición de los Grandes Vasos/cirugía
10.
J Biol Chem ; 297(3): 101076, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34391777

RESUMEN

Inwardly rectifying potassium channels (Kirs) are important drug targets, with antagonists for the Kir1.1, Kir4.1, and pancreatic Kir6.2/SUR1 channels being potential drug candidates for treating hypertension, depression, and diabetes, respectively. However, few peptide toxins acting on Kirs are identified and their interacting mechanisms remain largely elusive yet. Herein, we showed that the centipede toxin SsTx-4 potently inhibited the Kir1.1, Kir4.1, and Kir6.2/SUR1 channels with nanomolar to submicromolar affinities and intensively studied the molecular bases for toxin-channel interactions using patch-clamp analysis and site-directed mutations. Other Kirs including Kir2.1 to 2.4, Kir4.2, and Kir7.1 were resistant to SsTx-4 treatment. Moreover, SsTx-4 inhibited the inward and outward currents of Kirs with different potencies, possibly caused by a K+ "knock-off" effect, suggesting the toxin functions as an out pore blocker physically occluding the K+-conducting pathway. This conclusion was further supported by a mutation analysis showing that M137 located in the outer vestibule of the Kir6.2/ΔC26 channel was the key residue mediating interaction with SsTx-4. On the other hand, the molecular determinants within SsTx-4 for binding these Kir channels only partially overlapped, with K13 and F44 being the common key residues. Most importantly, K11A, P15A, and Y16A mutant toxins showed improved affinity and/or selectivity toward Kir6.2, while R12A mutant toxin had increased affinity for Kir4.1. To our knowledge, SsTx-4 is the first characterized peptide toxin with Kir4.1 inhibitory activity. This study provides useful insights for engineering a Kir6.2/SUR1 channel-specific antagonist based on the SsTx-4 template molecule and may be useful in developing new antidiabetic drugs.


Asunto(s)
Canales de Potasio de Rectificación Interna/metabolismo , Toxinas Biológicas/metabolismo , Animales , Quilópodos/enzimología , Quilópodos/metabolismo , Células HEK293 , Humanos , Mutagénesis Sitio-Dirigida , Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio de Rectificación Interna/antagonistas & inhibidores , Toxinas Biológicas/toxicidad
11.
Anal Bioanal Chem ; 414(22): 6557-6570, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35831534

RESUMEN

Molecularly imprinted polymers (MIPs) can exhibit antibody-level affinity for target molecules. However, the nonspecific adsorption of non-imprinted regions for non-target molecules limits the application range of MIPs. Herein, we fabricated PEGylated boronate-affinity-oriented ellagic acid-imprinting magnetic nanoparticles (PBEMN), which first integrated boronate-affinity-oriented surface imprinting and sequential PEGylation for small molecule-imprinted MIPs. The resultant PBEMN possess higher adsorption capacity and faster adsorption rate for template ellagic acid (EA) molecules than the non-PEGylated control. To prove the excellent performance, the PBEMN were linked with hydrophilic boronic acid-modified/fluorescein isothiocyanate-loaded graphene oxide (BFGO), because BFGO could selectively label cis-diol-containing substances by boronate-affinity and output ultrasensitive fluorescent signals. Based on a dual boronate-affinity synergy, the PBEMN first selectively captured EA molecules by boronate-affinity-oriented molecular imprinted recognition, and then the EA molecules were further labeled with BFGO through boronate-affinity. The PBEMN linked BFGO (PBPF) strategy provided ultrahigh sensitivity for EA molecules with a limit of detection of 39.1 fg mL-1, resulting from the low nonspecific adsorption of PBEMN and the ultrasensitive fluorescence signal of BFGO. Lastly, the PBPF strategy was successfully employed in the determination of EA concentration in a spiked beverage sample with recovery and relative standard deviation in the range of 96.5 to 104.2% and 3.8 to 5.1%, respectively. This work demonstrates that the integration of boronate-affinity-oriented surface imprinting and sequential PEGylation may be a universal tool for improving the performance of MIPs.


Asunto(s)
Nanopartículas de Magnetita , Impresión Molecular , Adsorción , Bebidas , Ácidos Borónicos , Ácido Elágico , Impresión Molecular/métodos
12.
Angew Chem Int Ed Engl ; 60(17): 9395-9400, 2021 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-33528075

RESUMEN

While the presence of sulfur⋅⋅⋅π bonding interaction is a general phenomenon in the biological systems, the exploitation of this noncovalent force in a chemical process yet remains elusive. Herein, we describe the concept of chalcogen⋅⋅⋅π bonding catalysis that activates molecules of π systems through the interaction between chalcogen and π-electron cloud. The proof-of-concept studies using a vinylindole-based Diels-Alder benchmark reaction demonstrate that S⋅⋅⋅π and Se⋅⋅⋅π bonding interaction can drive the cycloaddition reaction efficiently. Experimental results suggest that a simultaneously double Se⋅⋅⋅π bonding interaction directs the stereoselectivity in this cycloaddition process.

13.
Anal Bioanal Chem ; 410(1): 247-257, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29098333

RESUMEN

In this work, we reported an effective method for the synthesis of a multirecognition magnetic molecularly imprinted polymer (MMIP) with atom transfer radical polymerization (ATRP), using 2,4-diamino-6-methyl-1,3,5-triazine as pseudo-template. The resulting MMIP was characterized in detail by Fourier transform-infrared (FT-IR) spectra, scanning electron microscopy (SEM), thermogravimetic analysis (TGA), and vibrating sample magnetometry (VSM). These results indicated the successful synthesis of MMIP with sufficient thermal stability and magnetic properties. The adsorption experiments were carried out to evaluate the specific selectivity of MMIP related to the spatial structure of target molecules. The MMIP exhibited multirecognition ability and excellent binding capability for melamine (MEL), cyromazine (CYR), triamterene (TAT), diaveridine (DVD), and trimethoprim (TME), and the apparent maximum number of binding sites (Q max) was 77.5, 75.2, 72.5, 69.9, and 70.4 µmol g-1, respectively. The multirecognition MMIP not only possessed adequate magnetic responsiveness for fast separation but also avoided the risk of template leakage on trace component analysis. Therefore, it was suitable for serving as a magnetic solid-phase extraction (MSPE) adsorbent. MSPE coupled with high-performance liquid chromatography analysis was applied to enrich and separate five target molecules from three samples. Recoveries for all target molecules ranged from 81.6 to 91.5% with relative standard deviations of no more than 4.1% (n = 3). Graphical abstract Multirecognition property of magnetic molecularly imprinted polymer prepared with pseudo template.

14.
Opt Express ; 25(25): 31337-31346, 2017 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-29245809

RESUMEN

The field redistribution inside an X-ray cavity-QED setup with an embedded 57Fe layer is calculated and studied in detail. The destructive interference between two transitions from the ground state to the two upper dressed states causes that the cavity mode can not be driven. So the field intensity is very weak when the nuclear ensemble is resonant. Moreover, It is found that the resonant nuclear layer can play a role of reflective layer like a mirror and cut the size of the cavity, which will destroy the guided mode. To support this idea, we employ the 57Fe film as the bottom mirror layer of the cavity where a guided mode can only be formed at the resonant energy. Following this perspective, the electromagnetically induced transparency structure based on X-ray cavity-QED setup with nuclear ensemble is reviewed and a phenomenologically self-consistent analysis for the field redistribution is presented.

15.
Phys Rev Lett ; 116(19): 197402, 2016 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-27232044

RESUMEN

A control mechanism for stopping x-ray pulses in resonant nuclear media is investigated theoretically. We show that narrow-band x-ray pulses can be mapped and stored as nuclear coherence in a thin-film planar x-ray cavity with an embedded ^{57}Fe nuclear layer. The pulse is nearly resonant to the 14.4 keV Mössbauer transition in the ^{57}Fe nuclei. The role of the control field is played here by a hyperfine magnetic field which induces interference effects reminiscent of electromagnetically induced transparency. We show that, by switching off the control magnetic field, a narrow-band x-ray pulse can be completely stored in the cavity for approximately 100 ns. Additional manipulation of the external magnetic field can lead to both group velocity and phase control of the pulse in the x-ray cavity sample.

16.
J Colloid Interface Sci ; 663: 345-357, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38412720

RESUMEN

Hydrodeoxygenation of furfural over non-noble metal catalyst is an effective route to synthesis 2-methylfuran, but the reaction is often hampered by the low activity and selectivity of the catalyst. Herein, a bimetallic catalyst with CuCo alloy encapsulated in a hollow nitrogen-doped carbon cages (CuCo/NC) are fabricated by using ZIF-67 as a sacrificial template, which exhibited superior catalytic performance and a full conversion of furfural with a 95.7 % selectivity towards 2-methylfuran was achieved at an under relatively mild reaction conditions (150 ℃, 1.5 MPa H2 and 4.0 h). The characterizations and density functional theory calculations clearly evidenced that the introduced Cu species acts as a switch to regulate the activity and selectivity of the catalyst via two aspects. On the one hand, the Cu species perturb the Co electronic structure leading to adsorption configuration of furfural change from flat to vertical on the catalyst surface, which successfully hindered the hydrogenation of furan ring, resulting high selectivity towards 2-methylfuran. On the other hand, the formed CuCo (111) sites promotes the dissociation of hydrogen, cleavage of the CO bond and reduces the diffusion barrier of hydrogen so as to advance the formation of 2-methylfuran. This work may provide a feasible strategy for the design of nanoalloy catalyst for the hydrodeoxygenation of biomass platforms to value-added chemicals.

17.
Int J Biol Macromol ; 269(Pt 2): 132156, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38729480

RESUMEN

Reasonable design of non-noble metal catalysts with hollow open structure for hydrodeoxygenation (HDO) of lignin derivatives to value-added chemicals is of great significance but challenging. Herein, a novel MOF-derived multilayer hollow sphere coated nickel­tungsten bimetallic catalyst (Ni2-WOx@CN-700) was fabricated via by confined pyrolysis strategy using bimetallic MOFs as a self-sacrificial template, which exhibits robust activity for the typical model HDO of vanillin to 2-methoxy-4-methylphenol (Yield of 100 % at 140 °C for no less than 10 cycles). The characterizations revealed that WOx facilitated the dispersion of Ni nanoparticles and adjusted the acidic capacity of the catalyst through the formed Ni-WOx heterojunction. Density functional theory (DFT) calculations confirms that WOx species enhanced the electron-rich nature of the active sites, while the adsorption energies of H2 and vanillin on Ni-WOx decreased from -0.572 eV and - 0.622 eV on Ni to -3.969 eV and - 4.922 eV, respectively. These results further indicated that the high activity of Ni2-WOx@CN-700 was attributed to the Ni-WOx heterojunction. Based on the characterizations and the thermodynamic calculations, the reaction mechanism was proposed. In addition, the catalyst shows good substrate universality, which enables its good commercial application prospect.


Asunto(s)
Benzaldehídos , Níquel , Catálisis , Níquel/química , Benzaldehídos/química , Tungsteno/química , Lignina/química , Termodinámica , Estructuras Metalorgánicas/química , Adsorción , Teoría Funcional de la Densidad
18.
J Inflamm Res ; 17: 6485-6500, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39310903

RESUMEN

Background: Cardiovascular diseases, such as aortic valve calcification (AVC) and carotid atherosclerosis (CAS), impose substantial health challenges on a global scale. Both disorders have overlapping risk factors, which might trigger similar immune-inflammatory reactions in both diseases. Methods: Shared differentially expressed genes (DEGs) were identified in the AVC and CAS datasets from the Gene Expression Omnibus (GEO). Candidate hub genes associated with immunity were identified using LASSO and immune cell infiltration analysis, and single gene set enrichment analysis (GSEA) was performed on the datasets. Subsequently, the hub genes were confirmed by qRT‒PCR validation in tissue samples. Results: A total of 140 upregulated and 65 downregulated common genes were screened. Enrichment analyses highlighted immune system processes, response to stress, and cytokine pathways among the identified CEGs. LASSO identified candidate hub genes, including ANGPTL1, CX3CR1, and CCL4. Immune cell infiltration analysis emphasized the participation of immune cells, including macrophages, γδ T cells, and resting NK cells. The three hub genes were validated by qRT‒PCR analysis. Conclusion: Our study explored immunological processes, including immune-related genes and cells, involved in the development of AVC and CAS. In particular, the identified hub genes ANGPTL1, CX3CR1, and CCL4 play crucial roles in mediating immune-inflammatory responses, which are central to the pathogenesis of these cardiovascular diseases, and the involvement of these genes in key immune pathways suggests that they could serve as potential biomarkers for early diagnosis or as targets for therapeutic strategies.

19.
Front Public Health ; 11: 1160769, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37213643

RESUMEN

The current epidemic of Coronavirus Disease 2019 (COVID-19) has become a public health event worldwide. Through ethical analysis of a series of epidemic prevention phenomena and epidemic prevention measures taken by the Chinese (and other countries) government and medical institutions during the COVID-19 pandemic, this paper discusses a series of ethical difficulties in hospital emergency triage caused by the COVID-19, including the autonomy limitation of patients and waste of epidemic prevention resources due to over-triage, the safety problem of patients because of inaccurate feedback information from intelligent epidemic prevention technology, and conflicts between individual interests of patients and public interests due to the "strict" implementation of the pandemic prevention and control system. In addition, we also discuss the solution path and strategy of these ethical issues from the perspective of system design and implementation based on the Care Ethics theory.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Triaje , Pandemias/prevención & control , Salud Pública
20.
Front Med (Lausanne) ; 10: 1268046, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37964888

RESUMEN

Modern biomedical technology is in an era of dramatic development, which brings unprecedented challenges to the work of ethics review and provides a turning point for the construction of ethics review system. The current ethics review committee (ERC) in China is executed with low efficiency and quality, which can hardly meet the current needs of biomedical research involving human beings. This paper summarizes the main connotations and roles of the sign system technique and the discipline mechanism through the idea of Foucault's Panopticism, and proposes to incorporate the Panopticism into the construction of the ethics review system and establish the sign system and discipline mechanism of ethics review, in order to build an ethics review system and the operation system of the ethics review committee suitable for China's national conditions.

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