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1.
Sci Rep ; 14(1): 18981, 2024 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152179

RESUMO

Due to their interactions with the neurovasculature, microglia are implicated in maladaptive responses to hypobaric hypoxia at high altitude (HA). To explore these interactions at HA, pharmacological depletion of microglia with the colony-stimulating factor-1 receptor inhibitor, PLX5622, was employed in male C57BL/6J mice maintained at HA or sea level (SL) for 3-weeks, followed by assessment of ex-vivo hippocampal long-term potentiation (LTP), fear memory recall and microglial dynamics/physiology. Our findings revealed that microglia depletion decreased LTP and reduced glucose levels by 25% at SL but did not affect fear memory recall. At HA, the absence of microglia did not significantly alter HA associated deficits in fear memory or HA mediated decreases in peripheral glucose levels. In regard to microglial dynamics in the cortex, HA enhanced microglial surveillance activity, ablation of microglia resulted in increased chemotactic responses and decreased microglia tip proliferation during ball formation. In contrast, vessel ablation increased cortical microglia tip path tortuosity. In the hippocampus, changes in microglial dynamics were only observed in response to vessel ablation following HA. As the hippocampus is critical for learning and memory, poor hippocampal microglial context-dependent adaptation may be responsible for some of the enduring neurological deficits associated with HA.


Assuntos
Altitude , Cognição , Hipocampo , Potenciação de Longa Duração , Camundongos Endogâmicos C57BL , Microglia , Neurônios , Animais , Microglia/metabolismo , Microglia/fisiologia , Masculino , Camundongos , Hipocampo/metabolismo , Cognição/fisiologia , Neurônios/fisiologia , Neurônios/metabolismo , Aclimatação/fisiologia , Medo/fisiologia , Memória/fisiologia , Glucose/metabolismo , Compostos Orgânicos
2.
Inorg Chem ; 63(26): 12146-12155, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946339

RESUMO

The electrochemical conversion of nitrate pollutants into value-added ammonia (NH3) is an appealing alternative synthetic route for sustainable NH3 production. However, the development of the electrocatalytic nitrate-to-ammonia reduction reaction (NO3RR) has been hampered by unruly reactants and products at the interface and the accompanied sluggish kinetic rate. In this work, a built-in positive valence space is successfully constructed over FeCu nanocrystals to rationally regulate interfacial component concentrations and positively shift the chemical equilibrium. With positive valence Cu optimizing the active surface, the space between the stern and shear layers becomes positive, which is able to continuously attract the negatively charged NO3- reactant and repulse the positively charged NH4+ product even under high current density, thus significantly boosting the NO3RR kinetics. The system with a built-in positive valence space affords an ampere-level NO3RR performance with the highest NH3 yield rate of 150.27 mg h-1 mg-1 at -1.3 V versus RHE with an outstanding NH3 current density of 189.53 mA cm-2, as well as a superior Faradaic efficiency (FE) of 97.26% at -1.2 V versus RHE. The strategy proposed here underscores the importance of interfacial concentration regulation and can find wider applicability in other electrochemical syntheses suffering from sluggish kinetics.

3.
Sci Rep ; 14(1): 13261, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858469

RESUMO

Predicting and optimizing the mechanical performance of the helically wound nylon-reinforced rubber fertilizer hose (HWNR hose) is crucial for enhancing the performance of hose pumps. This study aims to enhance the service life of HWNR hoses and the efficiency of liquid fertilizer transport. First, a finite element simulation model and a mathematical model were established to analyze the influence of fiber layer arrangement on the maximum shear strain on the coaxial surface (MSS) and the reaction force on the extrusion roller (RF). For the first time, the Crested Porcupine Optimizer algorithm was used to improve the Generalized Regression Neural Network (CPO-GRNN) method to establish a surrogate model for predicting the mechanical properties of HWNR hoses, and it was compared with Response Surface Methodology (RSM). Results showed CPO-GRNN's superiority in handling complex nonlinear problems. Finally, the Non-dominated Sorting Genetic Algorithm II (NSGA-II) was employed for optimization design. Compared to the original HWNR hose with an MSS of 0.906 and an RF of 30,376N, the optimized design reduced the MSS by 7.99% and increased the RF by 2.46%, significantly enhancing their service life and liquid fertilizer transport capacity. However, further research on fatigue damage is needed.

4.
J Phys Chem Lett ; 15(20): 5495-5500, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38748898

RESUMO

Single-atom catalysts (SACs) have been widely studied in a variety of electrocatalysis. However, its application in the electrocatalytic nitrogen reduction reaction (NRR) field still suffers from unsatisfactory performance, due to the sluggish mass transfer and significant kinetic barriers. Herein, a novel rare-earth-lanthanum-evoked optimization strategy is proposed to boost ambient NRR over SACs. The incorporation of La with a large atomic radius tends to break the atomic long-range order and trigger the amorphization of SACs, endowing a greater density of dangling bonds that could modify affinity for reactants and adsorbates. Moreover, with unique 5d16s2 valence-electron configurations, its presence could further enrich the electron density and enhance the intrinsic activity of single-metal center via the valence orbital coupling. As expected, the La-modified catalyst presents excellent activity toward the electrochemical NRR, delivering a maximum ammonia yield rate of 33.91 µg h-1 mg-1 and a remarkable Faradaic efficiency of 53.82%.

5.
Talanta ; 276: 126212, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38723475

RESUMO

As a popular nutritional enhancer, casein phosphopeptides (CPPs) have attracted growing attention in food industry. However, conventional methods for CPPs detection are usually less precise or requires expensive instruments. Herein, a nanozyme-based colorimetric method was developed to achieve the quantitative detection of CPPs in food samples. This method is based on a facilely fabricated peroxidase-like nanozyme (Fe@UiO-66), which combines the specific binding of CPPs, as well as the nanozyme-catalyzed colorimetric sensing that can be easily detected by spectrometer. The method displayed good quantitative ability toward CPPs with the linear range of 2-30 µg/mL, the low limit of detection of 0.267 µg/mL and limit of quantification of 1.335 µg/mL. We highlighted the specificity, anti-interference and practicability of this method, by investigating the performances toward food samples. Besides, a smartphone-based colorimetric sensing platform was also established, which is conducive to the portable detection. The developed nanozyme-based colorimetric sensing method provides a promising strategy for CPPs detection in food samples.


Assuntos
Caseínas , Colorimetria , Fosfopeptídeos , Colorimetria/métodos , Caseínas/análise , Caseínas/química , Fosfopeptídeos/análise , Análise de Alimentos/métodos , Limite de Detecção , Estruturas Metalorgânicas/química , Animais
6.
bioRxiv ; 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38766026

RESUMO

Optical recording of intricate molecular dynamics is becoming an indispensable technique for biological studies, accelerated by the development of new or improved biosensors and microscopy technology. This creates major computational challenges to extract and quantify biologically meaningful spatiotemporal patterns embedded within complex and rich data sources, many of which cannot be captured with existing methods. Here, we introduce Activity Quantification and Analysis (AQuA2), a fast, accurate, and versatile data analysis platform built upon advanced machine learning techniques. It decomposes complex live imaging-based datasets into elementary signaling events, allowing accurate and unbiased quantification of molecular activities and identification of consensus functional units. We demonstrate applications across a wide range of biosensors, cell types, organs, animal models, and imaging modalities. As exemplar findings, we show how AQuA2 identified drug-dependent interactions between neurons and astroglia, and distinct sensorimotor signal propagation patterns in the mouse spinal cord.

7.
Angew Chem Int Ed Engl ; 63(27): e202402028, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38656658

RESUMO

A planar conjugated ligand functionalized with bithiophene and its Ru(II), Os(II), and Ir(III) complexes have been constructed as single-molecule platform for synergistic photodynamic, photothermal, and chemotherapy. The complexes have significant two-photon absorption at 808 nm and remarkable singlet oxygen and superoxide anion production in aqueous solution and cells when exposed to 808 nm infrared irradiation. The most potent Ru(II) complex Ru7 enters tumor cells via the rare macropinocytosis, locates in both nuclei and mitochondria, and regulates DNA-related chemotherapeutic mechanisms intranuclearly including DNA topoisomerase and RNA polymerase inhibition and their synergistic effects with photoactivated apoptosis, ferroptosis and DNA cleavage. Ru7 exhibits high efficacy in vivo for malignant melanoma and cisplatin-resistant non-small cell lung cancer tumors, with a 100 % survival rate of mice, low toxicity to normal cells and low residual rate. Such an infrared two-photon activatable metal complex may contribute to a new generation of single-molecule-based integrated diagnosis and treatment platform to address drug resistance in clinical practice and phototherapy for large, deeply located solid tumors.


Assuntos
Antineoplásicos , Complexos de Coordenação , Raios Infravermelhos , Fótons , Tiofenos , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/síntese química , Animais , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Tiofenos/química , Tiofenos/farmacologia , Camundongos , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/síntese química , Rutênio/química , Rutênio/farmacologia , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Terapia Fototérmica , Irídio/química , Estrutura Molecular , Apoptose/efeitos dos fármacos
8.
Plant Foods Hum Nutr ; 79(2): 526-530, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38530542

RESUMO

The antiglycation mechanisms of three structurally different salvianolic acids (Sals) including salvianolic acid A (Sal-A), salvianolic acid B (Sal-B) and salvianolic acid C (Sal-C) were investigated using the bovine serum albumin (BSA)-fructose model. The results showed that the three compounds could inhibit the formation of glycation products, maintain protein structural stability, mitigate the development of amyloid fibrils and scavenge radicals. Notably, Sal-A possessed the highest anti-glycated activity compared with Sal-B and Sal-C. This may be related to the fact that Sal-A contained the most molecules of caffeic acid (Sal-A, Sal-B, and Sal-C possessing two, one, and zero caffeic acid units, respectively), and caffeic acid played a leading role in the antiglycation properties relative to Danshensu. Moreover, these compounds quenched the intrinsic fluorescence intensity of BSA in a static mode, with the binding constants in the order of Sal-A > Sal-B > Sal-C. Obviously, Sal-A possessed the strongest binding affinity among these compounds, which may be one of the reasons why it exhibited the optimal antiglycation capability. Furthermore, molecular docking demonstrated that the three Sals exerted protective effects on BSA by preventing glycation modification of lysine and arginine residues. These findings would provide valuable insights into the potential application of Sals for alleviating non-enzymatic glycation of protein.


Assuntos
Benzofuranos , Ácidos Cafeicos , Lactatos , Polifenóis , Soroalbumina Bovina , Soroalbumina Bovina/química , Ácidos Cafeicos/farmacologia , Ácidos Cafeicos/química , Glicosilação/efeitos dos fármacos , Polifenóis/farmacologia , Polifenóis/química , Benzofuranos/farmacologia , Benzofuranos/química , Lactatos/farmacologia , Lactatos/química , Alcenos/farmacologia , Alcenos/química , Animais , Produtos Finais de Glicação Avançada/química , Produtos Finais de Glicação Avançada/metabolismo , Bovinos , Simulação de Acoplamento Molecular , Depsídeos
9.
Angew Chem Int Ed Engl ; 63(18): e202319029, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38449084

RESUMO

Electrochemical reduction of nitrate to ammonia (NO3RR) is a promising and eco-friendly strategy for ammonia production. However, the sluggish kinetics of the eight-electron transfer process and poor mechanistic understanding strongly impedes its application. To unveil the internal laws, herein, a library of Pd-based bimetallene with various transition metal dopants (PdM (M=Fe, Co, Ni, Cu)) are screened to learn their structure-activity relationship towards NO3RR. The ultra-thin structure of metallene greatly facilitates the exposure of active sites, and the transition metals dopants break the electronic balance and upshift its d-band center, thus optimizing intermediates adsorption. The anisotropic electronic characteristics of these transition metals make the NO3RR activity in the order of PdCu>PdCo≈PdFe>PdNi>Pd, and a record-high NH3 yield rate of 295 mg h-1 mgcat -1 along with Faradaic efficiency of 90.9 % is achieved in neutral electrolyte on PdCu bimetallene. Detailed studies further reveal that the moderate N-species (*NO3 and *NO2) adsorption ability, enhanced *NO activation, and reduced HER activity facilitate the NH3 production. We believe our results will give a systematic guidance to the future design of NO3RR catalysts.

10.
Breast Cancer Res ; 26(1): 26, 2024 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347619

RESUMO

BACKGROUND: MRI-based tumor shrinkage patterns (TSP) after neoadjuvant therapy (NAT) have been associated with pathological response. However, the understanding of TSP after early NAT remains limited. We aimed to analyze the relationship between TSP after early NAT and pathological response after therapy in different molecular subtypes. METHODS: We prospectively enrolled participants with invasive ductal breast cancers who received NAT and performed pretreatment DCE-MRI from September 2020 to August 2022. Early-stage MRIs were performed after the first (1st-MRI) and/or second (2nd-MRI) cycle of NAT. Tumor shrinkage patterns were categorized into four groups: concentric shrinkage, diffuse decrease (DD), decrease of intensity only (DIO), and stable disease (SD). Logistic regression analysis was performed to identify independent variables associated with pathologic complete response (pCR), and stratified analysis according to tumor hormone receptor (HR)/human epidermal growth factor receptor 2 (HER2) disease subtype. RESULTS: 344 participants (mean age: 50 years, 113/345 [33%] pCR) with 345 tumors (1 bilateral) had evaluable 1st-MRI or 2nd-MRI to comprise the primary analysis cohort, of which 244 participants with 245 tumors had evaluable 1st-MRI (82/245 [33%] pCR) and 206 participants with 207 tumors had evaluable 2nd-MRI (69/207 [33%] pCR) to comprise the 1st- and 2nd-timepoint subgroup analysis cohorts, respectively. In the primary analysis, multivariate analysis showed that early DD pattern (OR = 12.08; 95% CI 3.34-43.75; p < 0.001) predicted pCR independently of the change in tumor size (OR = 1.37; 95% CI 0.94-2.01; p = 0.106) in HR+/HER2- subtype, and the change in tumor size was a strong pCR predictor in HER2+ (OR = 1.61; 95% CI 1.22-2.13; p = 0.001) and triple-negative breast cancer (TNBC, OR = 1.61; 95% CI 1.22-2.11; p = 0.001). Compared with the change in tumor size, the SD pattern achieved a higher negative predictive value in HER2+ and TNBC. The statistical significance of complete 1st-timepoint subgroup analysis was consistent with the primary analysis. CONCLUSION: The diffuse decrease pattern in HR+/HER2- subtype and stable disease in HER2+ and TNBC after early NAT could serve as additional straightforward and comprehensible indicators of treatment response. TRIAL REGISTRATION: Trial registration at https://www.chictr.org.cn/ . REGISTRATION NUMBER: ChiCTR2000038578, registered September 24, 2020.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Humanos , Pessoa de Meia-Idade , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Terapia Neoadjuvante , Resultado do Tratamento , Receptor ErbB-2/genética , Imageamento por Ressonância Magnética , Valor Preditivo dos Testes , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Estudos Retrospectivos
11.
Water Sci Technol ; 89(3): 730-744, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38358499

RESUMO

The regional comprehensive economic partnership (RCEP) is today the largest free trade area in the world. This paper examines agricultural trade in the RCEP from 2010 to 2019 through the perspective of virtual water. And the drivers of the virtual water flow between China and the RCEP are also explored. The results are as follows: the virtual water flow during the study period was 2,576.51 billion m3. From a temporal perspective, the annual virtual water flow over the study period is characterized by a slow rise-significant fall-slow rise. It has the characteristics of concentration in spatial distribution and water resources and product structure. However, the concentration degree showed a downward trend during the study period. Then, we have divided the major trading into four categories based on whether there is a shortage of water on both sides of the trade. In terms of the drivers of virtual water flows between China and the RCEP, we have used the gravity model to arrive at the following findings: crop yields, bilateral economic scale, and agricultural labor resources are the main drivers. Our research results have reference values for adjusting bilateral agricultural trade and water conservation.


Assuntos
Comércio , Internacionalidade , Valores de Referência , Agricultura , Água
12.
Front Cell Infect Microbiol ; 14: 1322264, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38328671

RESUMO

With advances in medicine, increasing medical interventions have increased the risk of invasive fungal disease development. (1-3)-ß-D glucan (BDG) is a common fungal biomarker in serological tests. However, the scarcity of Limulus resources for BDG detection poses a challenge. This study addresses the need for an alternative to Limulus amebocyte lysate by using BDG mutant antibody for chemiluminescence detection. The wild-type BDG antibody was obtained by immunizing rabbits. An optimal V52HI/N34L Y mutant antibody, which has increased 3.7-fold of the testing efficiency compared to the wild-type antibody, was first achieved by mutating "hot-spot" residues that contribute to strong non-covalent bonds, as determined by alanine scanning and molecular dynamics simulation. The mutant was then applied to develop the magnetic particle chemiluminescence method. 574 clinical samples were tested using the developed method, with a cutoff value of 95 pg/mL set by Limulus amebocyte lysate. The receiver operating characteristic curve demonstrated an area under the curve of 0.905 (95% CI: 0.880-0.929). Chemiluminescence detected an antigen concentration of 89.98 pg/mL, exhibiting a sensitivity of 83.33% and specificity of 89.76%. In conclusion, the results showed a good agreement with Limulus amebocyte lysate and demonstrated the feasibility of using BDG mutant antibodies for invasive fungal disease diagnosis. The new method based on chemiluminescence for detecting BDG could shorten the sample-to-result time to approximately 30 min, rescue Limulus from being endangered and is resource efficient in terms of equipment and the non-use of a skilled technician.


Assuntos
Infecções Fúngicas Invasivas , beta-Glucanas , Animais , Coelhos , Caranguejos Ferradura , Curva ROC , Sequência de Bases , Sensibilidade e Especificidade
13.
J Phys Chem Lett ; 15(3): 733-743, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38226607

RESUMO

Solid composite electrolytes (SCEs) synergize inorganic and polymer merits for viable commercial application. However, inferior filler-polymer interfacial stability ultimately leads to the agglomeration of inorganic particles and greatly impedes Li+ migration. Herein, triethoxyvinylsilane (VTEO) is employed to form a strong chemical interaction between poly(vinylene carbonate) (PVC) and montmorillonite (MMT) via in situ solidification, which eliminates the agglomeration and improves interfacial compatibility. Consequently, the obtained solid composite electrolytes (PVC-s-MMT) achieve increased Li+ conductivity (0.4 mS cm-1 at 25 °C), enhanced transference number (0.74), and increased oxidation potential (5.2 V). The Li/PVC-s-MMT/LiFePO4 cells exhibit outstanding cycling performance (>99.5% after 600 cycles) at 1C at room temperature. Moreover, density functional theory (DFT) calculations are applied to uncover the fast interfacial conducting channels of PVC-s-MMT. Our work provides a feasible in situ synthesis method to prepare agglomeration-free SCEs, which is highly compatible with existing battery production processes of liquid electrolytes.

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