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1.
Sensors (Basel) ; 24(15)2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39124111

RESUMEN

Due to the increasing severity of aging populations in modern society, the accurate and timely identification of, and responses to, sudden abnormal behaviors of the elderly have become an urgent and important issue. In the current research on computer vision-based abnormal behavior recognition, most algorithms have shown poor generalization and recognition abilities in practical applications, as well as issues with recognizing single actions. To address these problems, an MSCS-DenseNet-LSTM model based on a multi-scale attention mechanism is proposed. This model integrates the MSCS (Multi-Scale Convolutional Structure) module into the initial convolutional layer of the DenseNet model to form a multi-scale convolution structure. It introduces the improved Inception X module into the Dense Block to form an Inception Dense structure, and gradually performs feature fusion through each Dense Block module. The CBAM attention mechanism module is added to the dual-layer LSTM to enhance the model's generalization ability while ensuring the accurate recognition of abnormal actions. Furthermore, to address the issue of single-action abnormal behavior datasets, the RGB image dataset RIDS (RGB image dataset) and the contour image dataset CIDS (contour image dataset) containing various abnormal behaviors were constructed. The experimental results validate that the proposed MSCS-DenseNet-LSTM model achieved an accuracy, sensitivity, and specificity of 98.80%, 98.75%, and 98.82% on the two datasets, and 98.30%, 98.28%, and 98.38%, respectively.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Humanos , Reconocimiento de Normas Patrones Automatizadas/métodos , Conducta/fisiología , Procesamiento de Imagen Asistido por Computador/métodos
2.
J Agric Food Chem ; 72(32): 18214-18224, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39101349

RESUMEN

Mogrosides are natural compounds highly valued in the food sector for their exceptional sweetness. Here, we report a novel O-glycosyltransferase (UGT74DD1) from Siraitia grosvenorii that catalyzes the conversion of mogrol to mogroside IIE. Site-directed mutagenesis yielded the UGT74DD1-W351A mutant, which exhibited the new capability to transform mogroside IIE into the valuable sweetener mogroside III, but with low catalytic activity. Subsequently, using structure-guided directed evolution with combinatorial active-site saturation testing, the superior mutant M6 (W351A/Q373 K/E49H/Q335W/S278C/D17F) were obtained, which showed a 46.1-fold increase in catalytic activity compared to UGT74DD1-W351A. Molecular dynamics simulations suggested that the enhanced activity and extended substrate profiles of M6 are due to its enlarged substrate-binding pocket and strengthened enzyme-substrate hydrogen bonding interactions. Overall, we redesigned UGT74DD1, yielding mutants that catalyze the conversion of mogrol into mogroside III. This study thus broadens the toolbox of UGTs capable of catalyzing the formation of valuable polyglycoside compounds.


Asunto(s)
Glicosiltransferasas , Edulcorantes , Glicosiltransferasas/genética , Glicosiltransferasas/química , Glicosiltransferasas/metabolismo , Edulcorantes/química , Edulcorantes/metabolismo , Cucurbitaceae/química , Cucurbitaceae/enzimología , Cucurbitaceae/genética , Cucurbitaceae/metabolismo , Mutagénesis Sitio-Dirigida , Proteínas de Plantas/genética , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Biocatálisis , Dominio Catalítico , Ingeniería de Proteínas , Especificidad por Sustrato , Cinética
3.
J Synchrotron Radiat ; 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39073994

RESUMEN

Achieving diffraction-limited performance in fourth-generation synchrotron radiation sources demands monochromator crystals that can preserve the wavefront across an unprecedented extensive range. There is an urgent need for techniques of absolute crystal diffraction wavefront measurement. At the Beijing Synchrotron Radiation Facility (BSRF), a novel edge scan wavefront metrology technique has been developed. This technique employs a double-edge tracking method, making diffraction-limited level absolute crystal diffraction wavefront measurement a reality. The results demonstrate an equivalent diffraction surface slope error below 70 nrad (corresponding to a wavefront phase error of 4.57% λ) r.m.s. within a nearly 6 mm range for a flat crystal in the crystal surface coordinate. The double-edge structure contributes to exceptional measurement precision for slope error reproducibility, achieving levels below 15 nrad (phase error reproducibility < λ/100) even at a first-generation synchrotron radiation source. Currently, the measurement termed double-edge scan (DES) has already been regarded as a critical feedback mechanism in the fabrication of next-generation crystals.

4.
Sci Total Environ ; 947: 174480, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38972400

RESUMEN

Reference evapotranspiration (ET0) estimation is crucial for efficient irrigation planning, optimized water management and ecosystem modeling, yet it presents significant challenges, particularly when meteorological data availability is limited. This study utilized remote sensing data of land surface temperature (LST), day of year, and latitude, and employed a machine learning approach (i.e., random forest) to develop an improved remote sensing ET0 model. The model performed excellently in 567 meteorological stations in China with an R2 of 0.97, RMSE of 0.40, MBE of 0.00, and MAPE of 0.11 compared to the FAO-PM ET0; it also performed well globally, yielding an average R2 of 0.97 and RMSE of 0.43 across 120 sites in mid-latitude (20°-50°) regions. This model demonstrates simplicity, accuracy, robust and generalization, holding great potential for widespread application, especially in the large-scale, high-resolution estimation of ET0. This study will contribute to advancements in water resources management, agricultural planning, and climate change studies.

5.
Biomater Sci ; 12(15): 3805-3825, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38967109

RESUMEN

Stimulus-responsive polymers have found widespread use in biomedicine due to their ability to alter their own structure in response to various stimuli, including internal factors such as pH, reactive oxygen species (ROS), and enzymes, as well as external factors like light. In the context of atherosclerotic cardiovascular diseases (CVDs), stimulus-response polymers have been extensively employed for the preparation of smart nanocarriers that can deliver therapeutic and diagnostic drugs specifically to inflammatory lesions. Compared with traditional drug delivery systems, stimulus-responsive nanosystems offer higher sensitivity, greater versatility, wider applicability, and enhanced biosafety. Recent research has made significant contributions towards designing stimulus-responsive polymer nanosystems for CVDs diagnosis and treatment. This review summarizes recent advances in this field by classifying stimulus-responsive polymer nanocarriers according to different responsiveness types and describing numerous stimuli relevant to these materials. Additionally, we discuss various applications of stimulus-responsive polymer nanomaterials in CVDs theranostics. We hope that this review will provide valuable insights into optimizing the design of stimulus-response polymers for accelerating their clinical application in diagnosing and treating CVDs.


Asunto(s)
Enfermedades Cardiovasculares , Nanomedicina Teranóstica , Humanos , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/terapia , Enfermedades Cardiovasculares/tratamiento farmacológico , Animales , Polímeros/química , Polímeros de Estímulo Receptivo/química , Especies Reactivas de Oxígeno/metabolismo , Portadores de Fármacos/química , Nanoestructuras/química , Nanopartículas/química , Concentración de Iones de Hidrógeno
6.
J Gene Med ; 26(7): e3718, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38979822

RESUMEN

BACKGROUND: Icariin (ICA) inhibits inflammatory response in various diseases, but the mechanism underlying ICA treating airway inflammation in asthma needs further understood. We aimed to predict and validate the potential targets of ICA against asthma-associated airway inflammation using network pharmacology and experiments. METHODS: The ovalbumin-induced asthma-associated airway inflammation mice model was established. The effects of ICA were evaluated by behavioral, airway hyperresponsiveness, lung pathological changes, inflammatory cell and cytokines counts. Next, the corresponding targets of ICA were mined via the SEA, CTD, HERB, PharmMapper, Symmap database and the literature. Pubmed-Gene and GeneCards databases were used to screen asthma and airway inflammation-related targets. The overlapping targets were used to build an interaction network, analyze gene ontology and enrich pathways. Subsequently, flow cytometry, quantitative real-time PCR and western blotting were employed for validation. RESULTS: ICA alleviated the airway inflammation of asthma; 402 targets of ICA, 5136 targets of asthma and 4531 targets of airway inflammation were screened; 216 overlapping targets were matched and predicted ICA possesses the potential to modulate asthmatic airway inflammation by macrophage activation/polarization. Additionally, ICA decreased M1 but elevated M2. Potential targets that were disrupted by asthma inflammation were restored by ICA treatment. CONCLUSIONS: ICA alleviates airway inflammation in asthma by inhibiting the M1 polarization of alveolar macrophages, which is related to metabolic reprogramming. Jun, Jak2, Syk, Tnf, Aldh2, Aldh9a1, Nos1, Nos2 and Nos3 represent potential targets of therapeutic intervention. The present study enhances understanding of the anti-airway inflammation effects of ICA, especially in asthma.


Asunto(s)
Asma , Modelos Animales de Enfermedad , Flavonoides , Activación de Macrófagos , Macrófagos Alveolares , Farmacología en Red , Animales , Asma/tratamiento farmacológico , Asma/metabolismo , Ratones , Flavonoides/farmacología , Flavonoides/uso terapéutico , Macrófagos Alveolares/efectos de los fármacos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/inmunología , Activación de Macrófagos/efectos de los fármacos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Citocinas/metabolismo , Ovalbúmina , Pulmón/patología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Femenino
7.
Front Bioeng Biotechnol ; 12: 1385986, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38983600

RESUMEN

Objective: 1. To assess the Inter-rater reliability and test-retest reliability of FPI-6 total score and individual scores in static foot posture evaluation among elderly female patients with knee osteoarthritis (KOA), aiming to establish the reliability of the FPI-6 scale. 2. To investigate the disparity between dominant and non-dominant quadriceps characteristics in elderly female KOA patients, as well as explore the correlation between quadriceps characteristics and abnormal foot posture, thereby offering novel insights for the prevention and treatment of KOA. Methods: The study enrolled a total of 80 lower legs of 40 participants (all female) with unilateral or bilateral KOA, who were assessed by two raters at three different time points. The inter-rater and test-retest reliability of the FPI-6 was evaluated using the intra-class correlation coefficient (ICC), while the absolute reliability of FPI-6 was examined using the standard error of measurement (SEM), minimum detectable change (MDC), and Bland-Altman analysis. The internal consistency of FPI-6 was assessed using Spearman's correlation coefficient. Additionally, MyotonPRO was employed to assess quadriceps muscle tone and stiffness in all participants, and the association between quadriceps muscle tone/stiffness and the total score of FPI-6 was analyzed. Result: Our study found excellent inter-rater and test-retest reliability (ICC values of 0.923 and 0.931, respectively) for the FPI-6 total score, as well as good to excellent reliability (ICC values ranging from 0.680 to 0.863 and 0.739-0.883) for individual items. The SEM and MDC values for the total score of FPI-6 among our study inter-rater were 0.78 and 2.15, respectively. and the SEM and MDC values for the test-retest total score of FPI-6 were found to be 0.76 and 2.11, respectively. Furthermore, the SEM and MDC values between inter-rater and test-retest across six individual items ranged from 0.30 to 0.56 and from 0.84 to 1.56. The Bland-Altman plots and respective 95% LOA showed no evidence of systematic bias. In terms of the mechanical properties of the quadriceps on both sides, the muscle tone and stiffness of rectus femoris (RF), vastus medialis (VM), and vastus lateralis (VL) were significantly higher in the non-dominant leg compared to the dominant leg. Additionally, in the non-dominant leg, there was a significant positive correlation between the muscle tone and stiffness of VM, VL, RF and the total score of FPI-6. However, in the dominant leg, only VM's muscle tone and stiffness showed a significant positive correlation with the total score of FPI-6. Conclusion: The reliability of the FPI-6 total score and its six individual items was good to excellent. Our findings offer a straightforward and dependable approach for researchers to assess foot posture in elderly female patients with KOA. Furthermore, we observed significantly greater quadriceps tension and stiffness in the non-dominant leg compared to the dominant leg. The FPI-6 total score exhibited a significant correlation with changes in quadriceps muscle performance among KOA patients. These observations regarding the relationship between changes in quadriceps muscle performance and foot posture in elderly female KOA patients may provide novel insights for disease prevention, treatment, and rehabilitation.

8.
Biochem Biophys Res Commun ; 731: 150394, 2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39024978

RESUMEN

Aflatoxin B1 (AFB1) not only causes significant losses in livestock production but also poses a serious threat to human health. It is the most carcinogenic among known chemicals. Pigs are more susceptible to AFB1 and experience a higher incidence. However, the molecular mechanism of the toxic effect of AFB1 remains unclear. In this study, we used assay for transposase-accessible chromatin using sequencing (ATAC-seq) and RNA-seq to uncover chromatin accessibility and gene expression dynamics in PK-15 cells during early exposure to AFB1. We observed that the toxic effects of AFB1 involve signaling pathways such as p53, PI3K-AKT, Hippo, MAPK, TLRs, apoptosis, autophagy, and cancer pathways. Basic leucine zipper (bZIP) transcription factors (TFs), including AP-1, Fos, JunB, and Fra2, play a crucial role in regulating the biological processes involved in AFB1 challenge. Several new TFs, such as BORIS, HNF1b, Atf1, and KNRNPH2, represent potential targets for the toxic mechanism of AFB1. In addition, it is crucial to focus on the concentration of intracellular zinc ions. These findings will contribute to a better understanding of the mechanisms underlying AFB1-induced nephrotoxicity and offer new molecular targets.

9.
Water Res ; 260: 121924, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38896885

RESUMEN

Drinking water treatment plants (DWTPs) in China that pioneered the biological activated carbon (BAC) process have reached 10 years of operation. There has been a renewed focus on biofiltration and the performance of old BAC filters for dissolved organic nitrogen (DON) has been poor, requiring replacement and regeneration of the BAC. Therefore, it is necessary to explore a cost-effective way to improve the water quality of the old BAC filters. To address this, low frequency ultrasound is proposed to enhance DON removal efficiency by BAC. In this study, bench and pilot tests were conducted to investigate the effect of low frequency ultrasound on DON removal by 10-year BAC. The results indicated that low frequency ultrasound significantly improved the DON removal rate increased from 15.83 % to 85.87 % and considerably inhibited the nitrogenous disinfection by-products (N-DBPs) formation potential, which was attributed to a decrease in the production of lipid-like, carbohydrate-like, and protein/amino sugar-like DON. The biomass on the BAC was significantly reduced after ultrasound treatment, and it decreased from 349.56∼388.98 nmol P/gBAC to 310.12∼377.63 nmol P/gBAC, enabling the biofilm thickness to decrease and the surface to become sparse and porous, which was conducive to oxygen and nutrients transfer. The Rhizobials associated with microbe-derived DON were stripped away during ultrasound treatment, which reduced microbe-derived DON associated with amino acids. Additionally, ultrasound regulated metabolic pathways, including amino acids, tricarboxylic acid (TCA) cycle, and nucleotide metabolism, to improve the osmotic pressure of the biofilm. In short, low frequency ultrasound treatment can enhance BAC biological properties and effectively remove DON and N-DBPs formation potentials, which provides a viable and promising strategy for improving the safety of drinking water in practice.


Asunto(s)
Carbón Orgánico , Nitrógeno , Purificación del Agua , Purificación del Agua/métodos , Carbón Orgánico/química , Biopelículas , Filtración
10.
ACS Appl Mater Interfaces ; 16(27): 35232-35244, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38917334

RESUMEN

The construction and modification of novel energetic frameworks to achieve an ideal balance between high energy density and good stability are a continuous pursuit for researchers. In this work, a fused [5,6,5]-tricyclic framework was utilized as the energetic host to encapsulate the oxidant molecules for the first time. A series of new pyridazine-based [5,6] and [5,6,5] fused polycyclic nitrogen-rich skeletons and their derivatives were designed and synthesized. Two strategies, amino oxidation and host-guest inclusion, were used to modify the skeleton in only one step. All compounds exhibit good comprehensive properties (Td (onset) > 200 °C, ρ > 1.85 g cm-3, Dv > 8400 m s-1, IS > 20 J, FS > 360 N). Benefiting from the pyridazine-based fused tricyclic structure with more hydrogen bonding units and larger conjugated systems, the first example of [5,6,5]-tricyclic host-guest energetic material triamino-9H-pyrazolo[3,4-d][1,2,4]triazolo[4,3-b]pyridazine-diperchloric acid (10), shows high decomposition temperature (Td (onset) = 336 °C), high density and heats of formation (ρ = 1.94 g cm-3, ΔHf = 733.4 kJ mol-1), high detonation performance (Dv = 8820 m s-1, P = 36.2 GPa), high specific impulse (Isp = 269 s), and low sensitivity (IS = 30 J, FS > 360 N). The comprehensive performance of 10 is superior to that of high-energy explosive RDX and heat-resistant explosives such as HNS and LLM-105. 10 has the potential to become a comprehensive advanced energetic material that simultaneously satisfies the requirements of high-energy and low-sensitivity explosives, heat-resistant explosives, and solid propellants. This work may give new insights into the construction and modification of a nitrogen-rich polycyclic framework and broaden the applications of fused polycyclic framework for the development of host-guest energetic materials.

11.
J Hazard Mater ; 476: 135010, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-38917632

RESUMEN

The content of active lattice oxygen and oxygen vacancies is crucial for the catalytic oxidation of soot. Herein, we adjust the Pr-O bond strength in Pr6O11 by doping several common transition metals (Mn, Fe, Co, Ni) to promote the formation of oxygen vacancies and the activation of lattice oxygen. This strategy does not compromise its crystal structure, allowing for improved catalytic performance while maintaining stability. The Mn-doped Pr6O11 catalyst shows the best soot catalytic oxidation performance. Its T50 (the temperature of soot conversion reaching 50 %) value is 396 °C under loose contact. Further characterizations and density functional theory (DFT) calculations demonstrate that PMO possesses a large specific surface area. Additionally, the weakening the strength of the Pr-O bond leaded to an increase in oxygen vacancies, which in turn enhanced the redox ability of catalyst. This work will provide a reference for the development of Pr-based catalysts for soot combustion.

12.
Bioresour Technol ; 406: 131044, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38936679

RESUMEN

The recovery of biopolymers, particularly alginate-like extracellular polymers, from municipal sludge represents a promising step toward sustainable sludge treatment practices. Originating from wastewater plants in complexly polluted environments, alginate-like extracellular polymers carry potential environmental risks concerning their reuse. This study employs ultrahigh-performance liquid chromatography-tandem mass spectrometry to investigate the distribution coefficients and occurrence of alginate-like extracellular polymers and sulfamethoxazole. Results demonstrate a negative distribution coefficient, suggesting an inhibitory effect on sulfamethoxazole dissolution. The ethanol-extracted alginate-like extracellular polymers exhibits higher sulfamethoxazole levels (approximately 52%) than those obtained via dialysis extraction. Three-dimensional excitation-emission matrix analysis and adsorption studies indicate the absence of tyrosine-like substances in the alginate-like extracellular polymers, unlike in other extracellular polymeric substances. This absence diminishes hydrophobic interactions, highlighting that electrostatic interactions play a more important role. These insights are crucial for understanding the adsorption behavior of alginate-like extracellular polymers and optimizing their large-scale extraction processes.


Asunto(s)
Alginatos , Aguas del Alcantarillado , Sulfametoxazol , Alginatos/química , Aguas del Alcantarillado/química , Adsorción , Ácido Glucurónico/química , Cromatografía Líquida de Alta Presión , Matriz Extracelular de Sustancias Poliméricas/química , Matriz Extracelular de Sustancias Poliméricas/metabolismo , Polímeros/química , Espectrometría de Masas en Tándem
13.
Chem Biodivers ; : e202401093, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38867371

RESUMEN

Two previously undescribed coumarins (1-2) were isolated from the root of Notopterygium incisum. The structures of new findings were elucidated by analyses of spectral evidences in HRESIMS, NMR, as well as ICD. The absolute configurations were further confirmed by chemical calculations. 1-2 exhibits obviously anti-inflammatory activity by inhibiting the expression of inflammatory mediators (COX-2, iNOS), as well as reducing the release of NO and the accumulation of ROS in cells. Western blotting analysis revealed that 2 could inhibit the PI3K/AKT pathway by reducing the expression of p-PI3K and p-AKT.

14.
J Cardiothorac Surg ; 19(1): 356, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38909234

RESUMEN

OBJECTIVE: Systematic evaluation of the safety of del Nido cardioplegia compared to cold blood cardioplegia in adult cardiac surgery. METHODS: We systematically searched PubMed, EMbase, The Cochrane Library and ClinicalTrials.gov for randomized clinical trials (published by 14 January 2024) comparing del Nido cardioplegia to cold blood cardioplegia in adult. Our main endpoints were myocardial injury markers and clinical outcomes. We assessed pooled data by use of a random-effects model or a fixed-effects model. RESULTS: A total of 10 studies were identified, incorporating 889 patients who received del Nido cardioplegia and 907 patients who received cold blood cardioplegia. The meta-analysis results showed that compared with the cold blood cardioplegia, the del Nido cardioplegia had less volume of cardioplegia, higher rate of spontaneous rhythm recovery after cross clamp release, lower levels of postoperative cardiac troponin T and creatinine kinase-myocardial band, all of which were statistically significant. However, there was no statistically significant difference in postoperative troponin I and postoperative left ventricular ejection fraction. The clinical outcomes including mechanical ventilation time, intensive care unit stay time, hospital stay time, postoperative stroke, postoperative new-onset atrial fibrillation, postoperative heart failure requiring intra-aortic balloon pump mechanical circulation support, and in-hospital mortality of both are comparable. CONCLUSION: Existing evidence suggests that del Nido cardioplegia reduced volume of cardioplegia administration and attempts of defibrillation. The superior postoperative results in CTnT and CK-MB may provide a direction for further research on improvement of the composition of cardioplegia.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Soluciones Cardiopléjicas , Paro Cardíaco Inducido , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Paro Cardíaco Inducido/métodos , Procedimientos Quirúrgicos Cardíacos/métodos , Soluciones Cardiopléjicas/uso terapéutico , Adulto , Cloruro de Potasio , Manitol , Lidocaína , Soluciones , Electrólitos , Sulfato de Magnesio , Bicarbonato de Sodio
15.
Chembiochem ; 25(13): e202400328, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38742991

RESUMEN

Baeyer-Villiger monooxygenases belong to a family of flavin-binding proteins that catalyze the Baeyer-Villiger (BV) oxidation of ketones to produce lactones or esters, which are important intermediates in pharmaceuticals or sustainable materials. Phenylacetone monooxygenase (PAMO) from Thermobifida fusca with moderate thermostability catalyzes the oxidation of aryl ketone substrates, but is limited by high specificity and narrow substrate scope. In the present study, we applied loop optimization by loop swapping followed by focused saturation mutagenesis in order to evolve PAMO mutants capable of catalyzing the regioselective BV oxidation of cyclohexanone and cyclobutanone derivatives with formation of either normal or abnormal esters or lactones. We further modulated PAMO to increase enantioselectivity. Crystal structure studies indicate that rotation occurs in the NADP-binding domain and that the high B-factor region is predominantly distributed in the catalytic pocket residues. Computational analyses further revealed dynamic character in the catalytic pocket and reshaped hydrogen bond interaction networks, which is more favorable for substrate binding. Our study provides useful insights for studying enzyme-substrate adaptations.


Asunto(s)
Oxigenasas de Función Mixta , Ingeniería de Proteínas , Thermobifida , Estereoisomerismo , Especificidad por Sustrato , Oxigenasas de Función Mixta/metabolismo , Oxigenasas de Función Mixta/química , Oxigenasas de Función Mixta/genética , Thermobifida/enzimología , Thermobifida/metabolismo , Oxidación-Reducción , Biocatálisis , Dominio Catalítico , Modelos Moleculares
16.
Artículo en Inglés | MEDLINE | ID: mdl-38734936

RESUMEN

Rheumatoid arthritis (RA) is an idiopathic and chronic autoimmune disease for which there are currently no effective treatments. Oxypeucedanin hydrate (OXH) is a natural coumarin known for its potent anti-inflammatory properties. However, further investigations are needed to determine its therapeutic efficacy in treating RA. In this study, we evaluate the anti-inflammatory activity of OXH by treating LPS-induced RAW264.7 macrophages. Our results show that OXH treatment reverses the changes in iNOS, COX-2, IL-1ß, IL-6, and TNF-α levels. Additionally, OXH reduces ROS production. Further analysis reveals that OXH suppresses the activation of the NF-κB/MAPK pathway. CETSA results show that OXH competes with LPS for binding to the TLR4/MD2 complex. MST experiments demonstrate the specific affinity of OXH for the TLR4/MD2 complex, with a Kd value of 33.7 µM. Molecular docking analysis suggests that OXH binds to the pocket of the TLR4/MD2 complex and interacts with specific amino acids, such as GLY-343, LYS-388, and PHE-345. Molecular dynamics simulations further confirm this conclusion. Finally, we investigate the potential of OXH in treating RA using a collagen-induced arthritis (CIA) model in rats. OXH effectively ameliorates the symptoms of CIA, including improving body weight, reducing swelling and redness, increasing talus volume, and decreasing bone erosion. OXH also decreases the mRNA levels of pro-inflammatory factors in synovial tissue. Transcriptome enrichment analysis and western blot analysis confirm that OXH suppresses the NF-κB/MAPK pathway, which is consistent with our in vitro findings.

17.
J Environ Manage ; 360: 121137, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38796874

RESUMEN

Understanding the relationship between hydrological connectivity (HC) and water level (WL) is crucial for effective water resource management and wetland restoration. However, current knowledge regarding this relationship is limited. This study proposed an integrated nonstationary and uncertain analysis framework (INUAF) to investigate the HC-WL relationship with reference to the Baiyangdian wetland, which is a fragmented wetland in North China. With the INUAF, the interannual and intra-annual variations of both HC and WL were examined, together with the wavelet coherence and lag effects between the two variables at multiple scales. The results highlighted marked nonstationarity in HC, WL, and the relationship between them. Scale-dependent lag effects revealed that HC lags WL by 37 days (131 days) at the 1 a scale (4 a scale), and leads WL by 190 days at the 8 a scale, indicating a complex coupled relationship between HC and WL. Additionally, the INUAF was applied to evaluating the uncertainty in the response of lagged HC to varied WL. Results indicated that every 0.2-m increase in WL led to a 2.2%-2.4% higher probability of maintaining high HC for WL between 6.0 and 8.0 m, but a 10%-11% higher probability for WL between 8.0 and 9.0 m. We suggest that a WL of > 8.4 m would produce a probability of > 50% for achieving high HC. These findings provide valuable insights into the HC-WL relationship and could contribute to wetland restoration efforts.


Asunto(s)
Hidrología , Humedales , China , Incertidumbre , Agua
18.
Oncoimmunology ; 13(1): 2355684, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38798746

RESUMEN

Identifying tumor-relevant T cell subsets in the peripheral blood (PB) has become a potential strategy for cancer treatment. However, the subset of PB that could be used to treat cancer remains poorly defined. Here, we found that the CX3CR1+ T cell subset in the blood of patients with lung cancer exhibited effector properties and had a higher TCR matching ratio with tumor-infiltrating lymphocytes (TILs) compared to CX3CR1- T cells, as determined by paired single-cell RNA and TCR sequencing. Meanwhile, the anti-tumor activities, effector cytokine production, and mitochondrial function were enhanced in CX3CR1+ T cells both in vitro and in vivo. However, in the co-culture system of H322 cells with T cells, the percentages of apoptotic cells and Fas were substantially higher in CX3CR1+ T cells than those in CX3CR1- T cells. Fas-mediated apoptosis was rescued by treatment with an anti-PD-1 antibody. Accordingly, the combination of adoptive transfer of CX3CR1+ T cells and anti-PD-1 treatment considerably decreased Fas expression and improved the survival of lung xenograft mice. Moreover, an increased frequency of CX3CR1+ T cells in the PB correlated with a better response and prolonged survival of patients with lung cancer who received anti-PD-1 therapy. These findings indicate the promising potential of adoptive transfer of peripheral CX3CR1+ T cells as an individual cancer immunotherapy.


Asunto(s)
Receptor 1 de Quimiocinas CX3C , Inhibidores de Puntos de Control Inmunológico , Neoplasias Pulmonares , Linfocitos Infiltrantes de Tumor , Receptor de Muerte Celular Programada 1 , Animales , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Receptor 1 de Quimiocinas CX3C/metabolismo , Humanos , Ratones , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Receptor de Muerte Celular Programada 1/metabolismo , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Linfocitos Infiltrantes de Tumor/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Línea Celular Tumoral , Femenino , Apoptosis/efectos de los fármacos , Masculino , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/metabolismo , Linfocitos T/inmunología , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo
19.
Phytomedicine ; 130: 155590, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38810547

RESUMEN

BACKGROUND: Staphylococcus aureus is a versatile pathogen that can cause a wide range of infections in humans. Biofilms play a crucial role in the pathogenicity of S. aureus and contribute to its ability to cause persistent and chronic infections. Baohuoside I has garnered increasing recognition as a natural flavonol glycoside with a wide spectrum of health-related activities. PURPOSE: The antibacterial and anti-biofilm properties of Baohuoside I have not been extensively investigated. Our study aimed to assess its inhibitory effects and the underlying mechanisms on biofilm formation and hemolytic capacity in S. aureus. STUDY DESIGN/METHODS: The impact of Baohuoside I on the biofilm and virulence of S. aureus was evaluated through in vitro experiments and Galleria mellonella as an in vivo infection model. The mechanisms were explored by Drug affinity responsive target stability (DARTS) and validated in genetic knockout strain and through molecular biological experiments using DARTS, molecular docking, electrophoretic mobility shift assay (EMSA), and bio-layer interferometry (BLI). RESULTS: Baohuoside I significantly inhibits the formation of S. aureus biofilms and hemolytic activity at 6.25 µM. Proteomics analysis revealed that treatment with Baohuoside I led to a reduction in the expression of quorum-sensing system agr-regulated genes. DARTS analysis identified Staphylococcus accessory regulator factor (SarZ), a key regulator involved in the expression of virulence factors in S. aureus by acting as activator of the agr quorum-sensing system, was the direct target of Baohuoside I. Molecular docking, DARTS, BLI and EMSA assays collectively confirmed the direct binding of Baohuoside I to SarZ, inhibiting its binding to downstream promoters. Furthermore, it is found through site-directed protein mutagenesis that the Tyr27 and Phe117 residues are key for Baohuoside I binding to SarZ. Additionally, the knockout of SarZ significantly diminished the hemolytic ability of S. aureus, underscoring its crucial role as a pivotal regulator of virulence. Lastly, in vivo tests utilizing the G. mellonella infection model demonstrated the efficacy of Baohuoside I. CONCLUSION: This study provides valuable insights into the mechanism by which Baohuoside I inhibits the virulence of S. aureus through its interaction with SarZ. These findings highlight the significance of SarZ as an effective target against the virulence of S. aureus.


Asunto(s)
Antibacterianos , Proteínas Bacterianas , Biopelículas , Simulación del Acoplamiento Molecular , Biopelículas/efectos de los fármacos , Animales , Virulencia/efectos de los fármacos , Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Mariposas Nocturnas/microbiología , Mariposas Nocturnas/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Hemólisis/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/patogenicidad , Pruebas de Sensibilidad Microbiana
20.
Anal Chem ; 96(18): 7091-7100, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38663871

RESUMEN

Detection of intracellular miRNAs, especially sensitive imaging of in vivo miRNAs, is vital to the precise prediction and timely prevention of tumorgenesis but remains a technical challenge in terms of nuclease resistance and signal amplification. Here, we demonstrate a gold nanoparticle-based spherical nucleic acid-mediated spatial matching-guided nonenzymatic DNA circuit (SSDC) for efficient screening of intracellular miRNAs and, in turn, finding cancerous tissues in living organisms before the appearance of clinical symptoms. Due to the substantially enhanced nuclease resistance, the false positive signal is avoided even in a complex biological medium. Target miRNA can straighten out the hairpin DNA probe to be linear, allowing the probe to penetrate into the internal region of a core/shell DNA-functionalized signal nanoampfilier and initiate a strand displacement reaction, generating an amplified fluorescence signal. The detection limit is as low as 17 pM, and miRNA imaging is in good accordance with the gold standard polymerase chain reaction method. The ability to image intracellular miRNAs is substantially superior to that of conventional fluorescence in situ hybridization techniques, making in vivo SSDC-based imaging competent for the precise prediction of tumorigenesis. By intratumoral chemotherapy guided by SSDC-based imaging, tumorigenesis and progression are efficiently controlled before the onset of clinical symptoms.


Asunto(s)
Oro , Nanopartículas del Metal , MicroARNs , Humanos , MicroARNs/análisis , Oro/química , Nanopartículas del Metal/química , Animales , Invasividad Neoplásica , ADN/química , Ratones , Neoplasias , Sondas de ADN/química
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