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1.
Sci Rep ; 14(1): 17768, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090133

RESUMEN

With the rapid development of Chinese transportation networks, such as the Sichuan-Tibet railway, numerous tunnels are under construction or planned in mountainous regions. Some of these tunnels must traverse or be situated near active fault zones, which could suffer damage from fault slip. In this study, the seismic response of a mountain tunnel subjected to coseismic faulting was analyzed using a fault-structure system in a two-step process. Firstly, a nonuniform slip model was proposed to calculate the ground deformations and internal displacements induced by a specific active fault on a geological scale, considering nonuniform slips on the fault plane. The 1989 Loma Prieta and 2022 Menyuan earthquakes were chosen as case studies to validate the proposed slip model. Secondly, the calculated displacement of the Menyuan earthquake was used as the input load for the discrete-continuous coupling analysis of the Daliang tunnel on an engineering scale. The simulated deformation of the Daliang tunnel aligned with the on-site damage observations following the Menyuan earthquake. Lastly, the effects of different fault conditions on the tunnel seismic response were investigated. The results indicate that the distribution of the peak longitudinal strain of the lining is governed by fault mechanisms, and the degree of fault slip significantly influences the response of the tunnel. A tunnel passing through an active fault with a wider fault fracture zone and smaller dip angle experience less damage.

3.
Immun Inflamm Dis ; 12(7): e1301, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38967361

RESUMEN

OBJECTIVE: Acute pancreatitis (AP) stands as a frequent cause for clinical emergency hospital admissions. The X-box binding protein 1 (XBP1) was found to be implicated in pancreatic acinar cell apoptosis. The objective is to unveil the potential mechanisms governed by XBP1 and SIRT6 in the context of AP. METHODS: Caerulein-treated human pancreatic duct epithelial (HPDE) cells to establish an in vitro research model. The levels and regulatory role of SIRT6 in the treated cells were evaluated, including its effects on inflammatory responses, oxidative stress, apoptosis, and endoplasmic reticulum stress. The relationship between XBP1 and SIRT6 was explored by luciferase and ChIP experiments. Furthermore, the effect of XBP1 overexpression on the regulatory function of SIRT6 on cells was evaluated. RESULTS: Caerulein promoted the decrease of SIRT6 and the increase of XBP1 in HPDE cells. Overexpression of SIRT6 slowed down the secretion of inflammatory factors, oxidative stress, apoptosis level, and endoplasmic reticulum stress in HPDE cells. However, XBP1 negatively regulated SIRT6, and XBP1 overexpression partially reversed the regulation of SIRT6 on the above aspects. CONCLUSION: Our study illuminates the role of XBP1 in downregulating SIRT6 in HPDE cells, thereby promoting cellular injury. Inhibiting XBP1 or augmenting SIRT6 levels holds promise in preserving cell function and represents a potential therapeutic avenue in the management of AP.


Asunto(s)
Apoptosis , Regulación hacia Abajo , Células Epiteliales , Conductos Pancreáticos , Pancreatitis , Sirtuinas , Proteína 1 de Unión a la X-Box , Humanos , Sirtuinas/metabolismo , Sirtuinas/genética , Células Epiteliales/metabolismo , Proteína 1 de Unión a la X-Box/metabolismo , Proteína 1 de Unión a la X-Box/genética , Pancreatitis/metabolismo , Pancreatitis/patología , Conductos Pancreáticos/metabolismo , Conductos Pancreáticos/patología , Estrés del Retículo Endoplásmico , Estrés Oxidativo , Línea Celular , Ceruletida/toxicidad
4.
Iran J Public Health ; 53(2): 313-322, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38894842

RESUMEN

Background: We systematically reviewed and analyzed the efficacy and safety of insulin degludec/insulin as-part (IDegAsp) versus biphasic insulin aspart 30 (BIAsp 30) in patients with type 2 diabetes (T2D). Methods: We used computers to search the Embase, PubMed, Clinical Trials, and the Cochrane Library database, and collected randomized controlled trials (RCTs) on the treatment of IDegAsp versus BIAsp 30 in T2D patients. The research period was from the establishment of the database to May 19, 2023. We used Review Manager 5.20 statistical software for systematic meta-analysis. Results: We included 8 RCTs with 2281 participants. IDegAsp was better to BIAsp30 in improving fasting plasma glucose (FPG) levels (P<0.001) and reducing the endpoint daily average insulin dose (P<0.01). Furthermore, compared with BIAsp30, IDegAsp significantly reduced the risk of nocturnal hypoglycemic events (P<0.001). However, there was no significant difference in the improvement of body weight change (P=0.99), glycosylated hemoglobin (P=0.50), the overall risk of hypoglycemic events (P=0.57) and adverse events (P=0.89) between the two groups. Conclusion: Compared with BIAsp30, IDegAsp could significantly reduce FPG levels, insulin dosage, and the risk of nocturnal hypoglycemic events in T2D patients, without increasing the overall risk of adverse events.

5.
BMC Cancer ; 24(1): 754, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38907215

RESUMEN

PURPOSE: Diffuse midline glioma (DMG), H3 K27M-mutant is a type of diffuse high-grade glioma that occurs in the brain midline carrying an extremely poor prognosis under the best efforts of surgery, radiation, and other therapies. For better therapy, we explored the efficacy and toxicity of a novel therapy that combines apatinib and temozolomide in DMG. METHODS: A retrospective analysis of 32 patients with DMG who underwent apatinib plus temozolomide treatment was performed. Apatinib was given 500 mg in adults, 250 mg in pediatric patients once daily. Temozolomide was administered at 200 mg/m2/d according to the standard 5/28 days regimen. The main clinical data included basic information of patients, radiological and pathological characteristics of tumors, treatment, adverse reactions, prognosis. RESULTS: The objective response rate was 24.1%, and the disease control rate was 79.3%. The median PFS of all patients was 5.8 months, and median OS was 10.3 months. A total of 236 cycles of treatment were available for safety assessment and the toxicity of the combination therapy was relatively well tolerated. The most common grade 3 toxicities were myelosuppression including leukopenia (5.08%), neutropenia (4.24%), lymphopenia (2.12%), thrombocytopenia (1.69%) and anemia (1.27%). Grade 4 toxicities included neutropenia (2.12%), thrombocytopenia (2.12%) and proteinuria (1.69%). All the adverse events were relieved after symptomatic treatment or dose reduction. CONCLUSIONS: Apatinib plus temozolomide could be an effective regimen with manageable toxicities and favorable efficacy and may outperform temozolomide monotherapy, particularly in newly diagnosed adults with tumors located outside the pons. The novel therapy deserves further investigation in adult DMG patients.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Encefálicas , Glioma , Piridinas , Temozolomida , Humanos , Temozolomida/administración & dosificación , Temozolomida/uso terapéutico , Temozolomida/efectos adversos , Femenino , Masculino , Adulto , Piridinas/administración & dosificación , Piridinas/efectos adversos , Piridinas/uso terapéutico , Glioma/tratamiento farmacológico , Glioma/patología , Adolescente , Estudios Retrospectivos , Niño , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Adulto Joven , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Preescolar , Persona de Mediana Edad , Resultado del Tratamiento
6.
ACS Appl Mater Interfaces ; 16(27): 34450-34466, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38941284

RESUMEN

Radiosensitizers play a pivotal role in enhancing radiotherapy (RT). One of the challenges in RT is the limited accumulation of nanoradiosensitizers and the difficulty in activating antitumor immunity. Herein, a smart strategy was used to achieve in situ aggregation of nanomanganese adjuvants (MnAuNP-C&B) to enhance RT-induced antitumor immunity. The aggregated MnAuNP-C&B system overcomes the shortcomings of small-sized nanoparticles that easily flow back into blood vessels and diffuse into surrounding tissues, and it also prolongs the retention time of nanomanganese within cancer cells and tumors. The MnAuNP-C&B system significantly enhances the radiosensitization effect in RT. Additionally, the pH-responsive disassembly of MnAuNP-C&B triggers the release of Mn2+, further promoting RT-induced activation of the STING pathway and eliciting robust antitumor immunity. Overall, our study presents a smart strategy wherein in situ aggregation of nanomanganese effectively inhibits tumor growth through radiosensitization and the activation of antitumor immunity.


Asunto(s)
Fármacos Sensibilizantes a Radiaciones , Animales , Ratones , Fármacos Sensibilizantes a Radiaciones/química , Fármacos Sensibilizantes a Radiaciones/farmacología , Humanos , Manganeso/química , Línea Celular Tumoral , Nanopartículas/química , Nanopartículas/uso terapéutico , Femenino , Ratones Endogámicos BALB C , Neoplasias/radioterapia , Neoplasias/inmunología , Antineoplásicos/química , Antineoplásicos/farmacología
7.
Environ Sci Technol ; 58(26): 11342-11351, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38875720

RESUMEN

Municipal solid waste (MSW) management systems play a crucial role in greenhouse gas (GHG) emissions in China. Although the government has implemented many policies to improve the MSW management system, the impact of these improvements on city-level GHG emission reduction remains largely unexplored. This study conducted a comprehensive analysis of both direct and downstream GHG emissions from the MSW sector, encompassing sanitary landfill, dump, incineration, and biological treatment, across 352 Chinese cities from 2001 to 2021 by adopting inventory methods recommended by the Intergovernmental Panel on Climate Change (IPCC). The results reveal that (1) GHG emissions from the MSW sector in China peaked at 70.6 Tg of CO2 equiv in 2018, followed by a significant decline to 47.6 Tg of CO2 equiv in 2021, (2) cities with the highest GHG emission reduction benefits in the MSW sector were historical emission hotspots over the past 2 decades, and (3) with the potential achievement of zero-landfilling policy by 2030, an additional reduction of 203.7 Tg of CO2 equiv is projected, with the emission reduction focus toward cities in South China (21.9%), Northeast China (17.8%), and Southwest China (17.3%). This study highlights that, even without explicit emission reduction targets for the MSW sector, the improvements of this sector have significantly reduced GHG emissions in China.


Asunto(s)
Gases de Efecto Invernadero , Residuos Sólidos , China , Ciudades , Eliminación de Residuos , Dióxido de Carbono/análisis
8.
Nanoscale ; 16(24): 11651-11662, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38847557

RESUMEN

A certain type of photoresist used for deep-UV lithography (DUVL) can also be used for other types of photolithography. Thus, to meet the requirements of two or more lithography technologies simultaneously, it is necessary to design a variety of corresponding functional groups in the molecules of materials and obtain the required properties. Herein, we designed four matrix resins based on acrylate for DUVL, employing alkyl sulfide, adamantane, methyladamantane, and hydroxyl as dangling groups and a microcrosslinking network by adding a small amount of crosslinker. These polymers were used in the thermal nanoimprint lithography (NIL) process, and distinct patterns with a resolution of 100 nm were observed. The acrylate copolymers designed for DUVL in this work can be used as thermal NIL resists and to obtain good patterns. It was found that ethylene dimethacrylate (EDMA) and adamantane endowed the matrix resins with good thermal stability and that PMMHM demonstrated the best patterning performance among the four resins. These polymers can be applied in the manufacturing of high-density integrated circuits, nano-transistors, optoelectronic devices and other components in the future.

9.
Adv Mater ; : e2404659, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38870958

RESUMEN

Single-atom electrocatalysts (SACs) are a class of promising materials for driving electrochemical energy conversion reactions due to their intrinsic advantages, including maximum metal utilization, well-defined active structures, and strong interface effects. However, SACs have not reached full commercialization for broad industrial applications. This review summarizes recent research achievements in the design of SACs for crucial electrocatalytic reactions on their active sites, coordination, and substrates, as well as the synthesis methods. The key challenges facing SACs in activity, selectivity, stability, and scalability, are highlighted. Furthermore, it is pointed out the new strategies to address these challenges including increasing intrinsic activity of metal sites, enhancing the utilization of metal sites, improving the stability, optimizing the local environment, developing new fabrication techniques, leveraging insights from theoretical studies, and expanding potential applications. Finally, the views are offered on the future direction of single-atom electrocatalysis toward commercialization.

10.
Adv Mater ; : e2404658, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38923073

RESUMEN

Catalysts play a crucial role in water electrolysis by reducing the energy barriers for hydrogen and oxygen evolution reactions (HER and OER). Research aims to enhance the intrinsic activities of potential catalysts through material selection, microstructure design, and various engineering techniques. However, the energy consumption of catalysts has often been overlooked due to the intricate interplay among catalyst microstructure, dimensionality, catalyst-electrolyte-gas dynamics, surface chemistry, electron transport within electrodes, and electron transfer among electrode components. Efficient catalyst development for high-current-density applications is essential to meet the increasing demand for green hydrogen. This involves transforming catalysts with high intrinsic activities into electrodes capable of sustaining high current densities. This review focuses on current improvement strategies of mass exchange, charge transfer, and reducing electrode resistance to decrease energy consumption. It aims to bridge the gap between laboratory-developed, highly efficient catalysts and industrial applications regarding catalyst structural design, surface chemistry, and catalyst-electrode interplay, outlining the development roadmap of hierarchically structured electrode-based water electrolysis for minimizing energy loss in electrocatalysts for water splitting.

11.
Adv Mater ; 36(33): e2402156, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38869191

RESUMEN

Producing green hydrogen in a cost-competitive manner via water electrolysis will make the long-held dream of hydrogen economy a reality. Although platinum (Pt)-based catalysts show good performance toward hydrogen evolution reaction (HER), the high cost and scarce abundance challenge their economic viability and sustainability. Here, a non-Pt, high-performance electrocatalyst for HER achieved by engineering high fractions of stacking fault (SF) defects for MoNi4/MoO2 nanosheets (d-MoNi) through a combined chemical and thermal reduction strategy is shown. The d-MoNi catalyst offers ultralow overpotentials of 78 and 121 mV for HER at current densities of 500 and 1000 mA cm-2 in 1 M KOH, respectively. The defect-rich d-MoNi exhibits four times higher turnover frequency than the benchmark 20% Pt/C, together with its excellent durability (> 100 h), making it one of the best-performing non-Pt catalysts for HER. The experimental and theoretical results reveal that the abundant SFs in d-MoNi induce a compressive strain, decreasing the proton adsorption energy and promoting the associated combination of *H into hydrogen and molecular hydrogen desorption, enhancing the HER performance. This work provides a new synthetic route to engineer defective metal and metal alloy electrocatalysts for emerging electrochemical energy conversion and storage applications.

12.
Int J Mol Sci ; 25(10)2024 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-38791272

RESUMEN

Renal fibrosis (RF) stands as a pivotal pathological process in the advanced stages of chronic kidney disease (CKD), and impeding its progression is paramount for delaying the advancement of CKD. The miR-10 family, inclusive of miR-10a and miR-10b, has been implicated in the development of various fibrotic diseases. Nevertheless, the precise role of miR-10 in the development of RF remains enigmatic. In this study, we utilized both an in vivo model involving unilateral ureteral obstruction (UUO) in mice and an in vitro model employing TGF-ß1 stimulation in HK-2 cells to unravel the mechanism underlying the involvement of miR-10a/b in RF. The findings revealed heightened expression of miR-10a and miR-10b in the kidneys of UUO mice, accompanied by a substantial increase in p-Smad3 and renal fibrosis-related proteins. Conversely, the deletion of these two genes led to a notable reduction in p-Smad3 levels and the alleviation of RF in mouse kidneys. In the in vitro model of TGF-ß1-stimulated HK-2 cells, the co-overexpression of miR-10a and miR-10b fostered the phosphorylation of Smad3 and RF, while the inhibition of miR-10a and miR-10b resulted in a decrease in p-Smad3 levels and RF. Further research revealed that miR-10a and miR-10b, through binding to the 3'UTR region of Vasohibin-1 (VASH-1), suppressed the expression of VASH-1, thereby promoting the elevation of p-Smad3 and exacerbating the progression of RF. The miR-10 family may play a pivotal role in RF.


Asunto(s)
Fibrosis , MicroARNs , Transducción de Señal , Proteína smad3 , MicroARNs/genética , MicroARNs/metabolismo , Animales , Proteína smad3/metabolismo , Proteína smad3/genética , Ratones , Humanos , Obstrucción Ureteral/metabolismo , Obstrucción Ureteral/patología , Obstrucción Ureteral/genética , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Crecimiento Transformador beta1/genética , Masculino , Línea Celular , Riñón/metabolismo , Riñón/patología , Modelos Animales de Enfermedad , Enfermedades Renales/metabolismo , Enfermedades Renales/genética , Enfermedades Renales/patología , Ratones Endogámicos C57BL , Moléculas de Adhesión Celular/metabolismo , Moléculas de Adhesión Celular/genética , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/genética , Insuficiencia Renal Crónica/patología
13.
Exp Eye Res ; 244: 109936, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38763351

RESUMEN

Non-infectious uveitis is an intraocular autoimmune disease mainly characterized by immune dysregulation of the eye, which may cause blindness if not well treated. Interleukin 10 (IL-10) is a potent cytokine with multiple immunoregulatory functions. However, it's in vivo activity is unstable owing to its inherent protein instability and short plasma half-life. Therefore, our previous research tried to establish IL-10-overexpressing MSC-sEVs (sEVs-IL10) using lentiviral transfection. While this approach indeed improved drug delivery, it also suffered from tedious procedures and limited loading efficiency. Accordingly, we constructed a novel MSC-sEVs-based delivery system for IL-10 (IL-10@sEVs) by sonication. The obtained formulation (IL-10@sEVs) had relatively higher loading efficiency and exerted a more profound immunomodulatory effect than sEVs-IL10 in vitro. Furthermore, IL-10@sEVs had significant therapeutic effects in a mouse model of experimental autoimmune uveitis (EAU) by decreasing the percentage of Th17 cells, increasing regulatory T cells in the eye, and draining lymph nodes. In summary, sonication outperforms conventional transfection methods for loading IL-10 into MSC-sEVs.


Asunto(s)
Enfermedades Autoinmunes , Vesículas Extracelulares , Interleucina-10 , Uveítis , Animales , Femenino , Ratones , Enfermedades Autoinmunes/tratamiento farmacológico , Modelos Animales de Enfermedad , Sistemas de Liberación de Medicamentos , Interleucina-10/genética , Ratones Endogámicos C57BL , Linfocitos T Reguladores/inmunología , Células Th17/inmunología , Transfección , Uveítis/tratamiento farmacológico
14.
Micromachines (Basel) ; 15(5)2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38793214

RESUMEN

In laser beam processing, the angle or offset between the auxiliary gas and the laser beam axis have been proved to be two new process optimization parameters for improving cutting speed and quality. However, a traditional electromechanical actuator cannot achieve high-speed and high-precision motion control with a compact structure. This paper proposes a magnetic levitation actuator which could realize the 5-DOF motion control of a lens using six groups of differential electromagnets. At first, the nonlinear characteristic of a magnetic driving force was analyzed by establishing an analytical model and finite element calculation. Then, the dynamic model of the magnetic levitation actuator was established using the Taylor series. And the mathematical relationship between the detected distance and five-degree-of-freedom was determined. Next, the centralized control system based on PID control was designed. Finally, a driving test was carried out to verify the five-degrees-of-freedom motion of the proposed electromagnetic levitation actuator. The results show it can achieve a stable levitation and precision positioning with a desired command motion. It also proves that the proposed magnetic levitation actuator has the potential application in an off-axis laser cutting machine tool.

15.
Stem Cell Res Ther ; 15(1): 149, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38783393

RESUMEN

BACKGROUND: Autoimmune uveitis is an inflammatory disease triggered by an aberrant immune response. Mesenchymal stem cell-derived small extracellular vesicles (MSC-sEVs) are emerging as potential therapeutic agents for this condition. CD73, an ectoenzyme present on MSC-sEVs, is involved in mitigating inflammation by converting extracellular adenosine monophosphate into adenosine. We hypothesize that the inhibitory effect of MSC-sEVs on experimental autoimmune uveitis (EAU) could be partially attributed to the surface expression of CD73. METHODS: To investigate novel therapeutic approaches for autoimmune uveitis, we performed lentiviral transduction to overexpress CD73 on the surface of MSC-sEVs, yielding CD73-enriched MSC-sEVs (sEVs-CD73). Mice with interphotoreceptor retinoid-binding protein (IRBP)-induced EAU were grouped randomly and treated with 50 µg MSC-sEVs, vector infected MSC-sEVs, sEVs-CD73 or PBS via single tail vein injection. We evaluated the clinical and histological features of the induced mice and analyzed the proportion and functional capabilities of T helper cells. Furthermore, T-cells were co-cultured with various MSC-sEVs in vitro, and we quantified the resulting inflammatory response to assess the potential therapeutic benefits of sEVs-CD73. RESULTS: Compared to MSC-sEVs, sEVs-CD73 significantly alleviates EAU, leading to reduced inflammation and diminished tissue damage. Treatment with sEVs-CD73 results in a decreased proportion of Th1 cells in the spleen, draining lymph nodes, and eyes, accompanied by an increased proportion of regulatory T-cells (Treg cells). In vitro assays further reveal that sEVs-CD73 inhibits T-cell proliferation, suppresses Th1 cells differentiation, and enhances Treg cells proportion. CONCLUSION: Over-expression of CD73 on MSC-sEVs enhances their immunosuppressive effects in EAU, indicating that sEVs-CD73 has the potential as an efficient immunotherapeutic agent for autoimmune uveitis.


Asunto(s)
5'-Nucleotidasa , Enfermedades Autoinmunes , Vesículas Extracelulares , Células Madre Mesenquimatosas , Uveítis , Animales , Uveítis/patología , Uveítis/terapia , Uveítis/metabolismo , Uveítis/inmunología , 5'-Nucleotidasa/metabolismo , 5'-Nucleotidasa/genética , Vesículas Extracelulares/metabolismo , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/inmunología , Ratones , Enfermedades Autoinmunes/terapia , Enfermedades Autoinmunes/patología , Enfermedades Autoinmunes/inmunología , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Femenino , Proteínas de Unión al Retinol , Humanos
16.
Adv Mater ; 36(29): e2401568, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38682861

RESUMEN

The development of high-performance electrocatalysts for energy conversion reactions is crucial for advancing global energy sustainability. The design of catalysts based on their electronic properties (e.g., work function) has gained significant attention recently. Although numerous reviews on electrocatalysis have been provided, no such reports on work function-guided electrocatalyst design are available. Herein, a comprehensive summary of the latest advancements in work function-guided electrocatalyst design for diverse electrochemical energy applications is provided. This includes the development of work function-based catalytic activity descriptors, and the design of both monolithic and heterostructural catalysts. The measurement of work function is first discussed and the applications of work function-based catalytic activity descriptors for various reactions are fully analyzed. Subsequently, the work function-regulated material-electrolyte interfacial electron transfer (IET) is employed for monolithic catalyst design, and methods for regulating the work function and optimizing the catalytic performance of catalysts are discussed. In addition, key strategies for tuning the work function-governed material-material IET in heterostructural catalyst design are examined. Finally, perspectives on work function determination, work function-based activity descriptors, and catalyst design are put forward to guide future research. This work paves the way to the work function-guided rational design of efficient electrocatalysts for sustainable energy applications.

17.
Angew Chem Int Ed Engl ; 63(19): e202400177, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38488857

RESUMEN

Mn(I)-catalyzed enantioselective C-C bond-forming reactions represent a great challenge in homogeneous catalysis primarily due to a limited understanding of its mechanistic principles. Herein, we have developed an interesting catalytic strategy that leverages a synergistic combination of a dimeric manganese(I) catalyst and a chiral aminocatalyst to address this issue. A range of conjugated dienals and trienals can exclusively proceed 1,4-hydroalkenylation by using readily available aromatic and aliphatic alkenyl boronic acids as coupling partners, producing a rich library of skipped diene aldehydes in synthetically useful yields and high levels of enantioselectivities. Notably, downstream transformations of these products can not only afford a concise approach to construct enantioenriched skipped trienes but also realize enantioselective total synthesis of analogues to (-)-Blepharocalyxin D in four steps. DFT calculations suggest the 1,4-hydroalkenylation is kinetically more favorable than 1,6-hydroalkenylation.

18.
Small Methods ; 8(8): e2301373, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38353380

RESUMEN

A facile NMR method is reported for analysis of ammonia from the electrochemical reduction of nitrogen, which compares a calibrated colorimetric method, a calibrated 1H NMR method and two 1H NMR direct measurements using external reference materials. Unlike spectrophotometric methods, 1H NMR requires less bench time and does not require separation of ammonia from the electrolyte. A novel approach to the problem of radiation damping in NMR measurements considered the specific role of hardware tuning. Radiation damping is suppressed improving signal-to-noise ratio and detection limit (1.5 µg L-1). The method is demonstrated to be effective for the analysis of ammonia from direct electrochemical nitrogen reduction in KOH, and from lithium-mediated nitrogen reduction in a non-aqueous solution. An uncertainty budget is prepared for the measurement of ammonia.

19.
Adv Mater ; 36(21): e2313378, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38340031

RESUMEN

Green hydrogen, derived from water splitting powered by renewable energy such as solar and wind energy, provides a zero-emission solution crucial for revolutionizing hydrogen production and decarbonizing industries. Catalysts, particularly those utilizing defect engineering involving the strategical introduction of atomic-level imperfections, play a vital role in reducing energy requirements and enabling a more sustainable transition toward a hydrogen-based economy. Stacking fault (SF) defects play an important role in enhancing the electrocatalytic processes by reshaping surface reactivity, increasing active sites, improving reactants/product diffusion, and regulating electronic structure due to their dense generation ability and profound impact on catalyst properties. This review explores SF in metal-based materials, covering synthetic methods for the intentional introduction of SF and their applications in hydrogen production, including oxygen evolution reaction, photo- and electrocatalytic hydrogen evolution reaction, overall water splitting, and various other electrocatalytic processes such as oxygen reduction reaction, nitrate reduction reaction, and carbon dioxide reduction reaction. Finally, this review addresses the challenges associated with SF-based catalysts, emphasizing the importance of a detailed understanding of the properties of SF-based catalysts to optimize their electrocatalytic performance. It provides a comprehensive overview of their various applications in electrocatalytic processes, providing valuable insights for advancing sustainable energy technologies.

20.
J Ethnopharmacol ; 326: 117965, 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38423410

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Scrophulariae Radix (Xuanshen [XS]) has been used for several years to treat hyperthyroidism. However, its effective substances and pharmacological mechanisms in the treatment of hyperthyroidism and thyroid hormone-induced liver and kidney injuries have not yet been elucidated. AIM OF THE STUDY: This study aimed to explore the pharmacological material basis and potential mechanism of XS therapy for hyperthyroidism and thyroid hormone-induced liver and kidney injuries based on network pharmacology prediction and experimental validation. MATERIALS AND METHODS: Based on 31 in vivo XS compounds identified using ultra-performance liquid chromatography tandem quadruple exactive orbitrap high-resolution accurate-mass spectrometry (UPLC-QE-HRMS), a network pharmacology approach was used for mechanism prediction. Systematic networks were constructed to identify the potential molecular targets, biological processes (BP), and signaling pathways. A component-target-pathway network was established. Mice were administered levothyroxine sodium through gavage for 30 d and then treated with different doses of XS extract with or without propylthiouracil (PTU) for 30 d. Blood, liver, and kidney samples were analyzed using an enzyme-linked immunosorbent assay (ELISA) and western blotting. RESULTS: A total of 31 prototypes, 60 Phase I metabolites, and 23 Phase II metabolites were tentatively identified in the plasma of rats following the oral administration of XS extract. Ninety-six potential common targets between the 31 in vivo compounds and the diseases were identified. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that Bcl-2, BAD, JNK, p38, and ERK1/2 were the top targets. XS extract with or without PTU had the following effects: inhibition of T3/T4/fT3/fT4 caused by levothyroxine; increase of TSH levels in serum; restoration of thyroid structure; improvement of liver and kidney structure and function by elevating the activities of anti-oxidant enzymes catalase (CAT),superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px); activation anti-apoptotic proteins Bcl-2; inhibition the apoptotic protein p-BAD; downregulation inflammation-related proteins p-ERK1/2, p-JNK, and p-p38; and inhibition of the aggregation of pro-inflammatory cytokines TNF-α, IL-1ß, and IL-6, as well as immune cells in the liver. CONCLUSION: XS can be used to treat hyperthyroidism and liver and kidney injuries caused by thyroid hormones through its anti-oxidant, anti-inflammatory, and anti-apoptotic properties. In addition, serum pharmacochemical analysis revealed that five active compounds, namely 4-methylcatechol, sugiol, eugenol, acetovanillone, and oleic acid, have diverse metabolic pathways in vivo and exhibit potential as effective therapeutic agents.


Asunto(s)
Medicamentos Herbarios Chinos , Hipertiroidismo , Ratas , Ratones , Animales , Antioxidantes/farmacología , Farmacología en Red , Hígado , Hormonas Tiroideas/metabolismo , Hipertiroidismo/inducido químicamente , Hipertiroidismo/tratamiento farmacológico , Tiroxina , Riñón/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Antiinflamatorios/farmacología , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Medicamentos Herbarios Chinos/metabolismo , Simulación del Acoplamiento Molecular
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