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1.
Phytochemistry ; 222: 114071, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38552709

RESUMO

Eight pairs of dihydrohomoisoflavonoids (1-8), including four pairs of enantiomeric aglycones [(R,S)-portulacanones B (1) and C (2) and (R,S)-oleracones C (3) and Q (4)] and four pairs of epimeric glycosides [portulacasides A-D and epiportulacasides A-D (5-8)], were obtained from Portulaca oleracea L. Among them, (R,S)-oleracone Q (4) and four pairs of epimeric glycosides (5-8) were reported for the first time. The 50% EtOH fraction from the 70% EtOH extract prevented HepG2 human liver cancer cell damage induced by N-acetyl-p-aminophenol (APAP), and the cell survival rate was 62.3%. Portulacaside B (6a), which was isolated from the 50% EtOH fraction, exhibited hepatoprotective and anti-inflammatory effects. The compound increased the survival rate of APAP-damaged HepG2 human liver cancer cells from 40.0% to 51.2% and reduced nitric oxide production in RAW 264.7 macrophages, resulting in an inhibitory rate of 46.8%.


Assuntos
Sobrevivência Celular , Portulaca , Humanos , Portulaca/química , Camundongos , Animais , Células Hep G2 , Células RAW 264.7 , Sobrevivência Celular/efeitos dos fármacos , Estrutura Molecular , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/química , Óxido Nítrico/biossíntese , Óxido Nítrico/antagonistas & inibidores , Glicosídeos/química , Glicosídeos/farmacologia , Glicosídeos/isolamento & purificação , Acetaminofen/farmacologia , Relação Estrutura-Atividade , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação
2.
Front Endocrinol (Lausanne) ; 15: 1291895, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38419954

RESUMO

Introduction: The ratio of Triglyceride (TG) to high-density lipoprotein cholesterol (HDL-C) is a crucial indicator for diabetes diagnosis. Methods: This study utilizes the Copula function to model and fit the non-linear correlation among fasting blood glucose (Glu), glycosylated hemoglobin (HbA1C), and TG/HDL-C in patients with diabetes. The Copula function chosen for this study includes the two-dimensional Archimedes and Elliptical distribution family, as well as the multidimensional Vine Copula function, for fitting the data. The evaluation of the fitting effect is performed using the mean absolute error (MAE) and mean square error (MSE). Results: The results indicate that the Clayton Copula exhibits the highest effectiveness in fitting the pairwise relationship between Glu and TG/HDL-C, as well as HbA1C and TG/HDL-C, displaying the smallest fitting error. Additionally, the Vine Copula function produces a satisfactory fit for the relationship among all three indicators. Compared to linear analysis methods, the Copula function more accurately depicts the correlation among these three types of indicators. Discussion: Moreover, our findings indicate a stronger correlation in the lower tail between Glu and HbA1C, as well as TG/HDL-C, suggesting that the Copula function provides greater accuracy and applicability in depicting the relationship among these indicators. As a result, it can offer a more precise auxiliary diagnosis and serve as a valuable reference in clinical judgment.


Assuntos
Glicemia , Diabetes Mellitus , Humanos , Hemoglobinas Glicadas , Diabetes Mellitus/diagnóstico , Triglicerídeos , HDL-Colesterol
3.
Small ; : e2311129, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319033

RESUMO

Constructing concentration differences between anions and cations at the ends of an ionic conductor is an effective strategy in electricity generation for powering wearable devices. Temperature gradient or salinity gradient is the driving force behind such devices. But their corresponding power generation devices are greatly limited in actual application due to their complex structure and harsh application conditions. In this study, a novel ionic concentration gradient electric generator based on the evaporation difference of the electrolyte is proposed. The device can be constructed without the need for semipermeable membranes, and operation does not need to build a temperature difference. As a demonstration, a PVA-Na ionic hydrogel is prepared as an electrolyte for the device and achieved a thermovoltage of more than 200 mV and an energy density of 77.94 J m-2 at 323 K. Besides, the device exhibits the capability to sustain a continuous voltage output for a duration exceeding 1500 min, as well as enabling charging and discharging cycles for 100 iterations. For practical applications, a module comprising 16 sub-cells is constructed and successfully utilized to directly power a light-emitting diode. Wearable devices and their corresponding cell modules are also developed to recycle body heat.

4.
J Orthop Surg Res ; 19(1): 38, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38183110

RESUMO

BACKGROUND: Surgical site infection (SSI) is a common and serious complication of elective clean orthopedic surgery that can lead to severe adverse outcomes. However, the prognostic efficacy of the current staging systems remains uncertain for patients undergoing elective aseptic orthopedic procedures. This study aimed to identify high-risk factors independently associated with SSI and develop a nomogram prediction model to accurately predict the occurrence of SSI. METHODS: A total of 20,960 patients underwent elective clean orthopedic surgery in our hospital between January 2020 and December 2021, of whom 39 developed SSI; we selected all 39 patients with a postoperative diagnosis of SSI and 305 patients who did not develop postoperative SSI for the final analysis. The patients were randomly divided into training and validation cohorts in a 7:3 ratio. Univariate and multivariate logistic regression analyses were conducted in the training cohort to screen for independent risk factors of SSI, and a nomogram prediction model was developed. The predictive performance of the nomogram was compared with that of the National Nosocomial Infections Surveillance (NNIS) system. Decision curve analysis (DCA) was used to assess the clinical decision-making value of the nomogram. RESULTS: The SSI incidence was 0.186%. Univariate and multivariate logistic regression analysis identified the American Society of Anesthesiology (ASA) class (odds ratio [OR] 1.564 [95% confidence interval (CI) 1.029-5.99, P = 0.046]), operative time (OR 1.003 [95% CI 1.006-1.019, P < 0.001]), and D-dimer level (OR 1.055 [95% CI 1.022-1.29, P = 0.046]) as risk factors for postoperative SSI. We constructed a nomogram prediction model based on these independent risk factors. In the training and validation cohorts, our predictive model had concordance indices (C-indices) of 0.777 (95% CI 0.672-0.882) and 0.732 (95% CI 0.603-0.861), respectively, both of which were superior to the C-indices of the NNIS system (0.668 and 0.543, respectively). Calibration curves and DCA confirmed that our nomogram model had good consistency and clinical predictive value, respectively. CONCLUSIONS: Operative time, ASA class, and D-dimer levels are important clinical predictive indicators of postoperative SSI in patients undergoing elective clean orthopedic surgery. The nomogram predictive model based on the three clinical features demonstrated strong predictive performance, calibration capabilities, and clinical decision-making abilities for SSI.


Assuntos
Infecção Hospitalar , Procedimentos Ortopédicos , Ortopedia , Humanos , Estudos Retrospectivos , Nomogramas , Infecção da Ferida Cirúrgica/diagnóstico , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Procedimentos Ortopédicos/efeitos adversos
5.
Knee ; 46: 117-127, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38071924

RESUMO

PURPOSE: This study aimed to compare the regeneration status of articular cartilage, clinical, and radiologic outcomes between varus knee patients with and without preoperative tibial varus deformity (PTVD) after medial opening-wedge high tibial osteotomy (OWHTO) METHODS: Varus knee patients who had undergone OWHTO were divided into two groups according to preoperative medial proximal tibial angle (MPTA): a great varus (GV) group (MPTA <85°) and a mild varus (MV) group (85°≤preoperative MPTA <87°). The hip-knee-ankle (HKA) angle, weight-bearing line ratio (WBL%), MPTA, joint line convergence angle and joint line obliquity were measured. Second-look arthroscopy was undertaken 24 months after HTO. The Knee Society (KS) function score and knee score, and Lysholm score were used to evaluate the functional outcomes. All parameters were evaluated preoperatively and 24 months after HTO. RESULTS: The GV group had greater varus than the MV group in HKA and WBL% before surgery, but greater valgus after surgery. The arthroscopic probe before HTO revealed the advanced chondral damage in the GV group and lighter chondral damage in the MV group. The regeneration of medial femoral condyle was considerably more frequent in the GV group (72.5%, 45/62) than in the MV group (50.0%, 27/54) (P = 0.030). No significant differences were observed in all functional outcomes preoperatively and 24 months after HTO. CONCLUSION: The extent of cartilage regeneration in patients without PTVD was inferior to that in those with PTVD, but the functional outcomes were comparable. OWHTO may be a treatment option in a selected subset of varus knee patients without PTVD.


Assuntos
Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Extremidade Inferior , Osteotomia/métodos , Estudos Retrospectivos
6.
Int J Biol Macromol ; 254(Pt 3): 128008, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37951068

RESUMO

In order to improve the removal rate of uranium and reduce the harm of radioactive pollution, a physically crosslinked polyvinyl alcohol/phosphorylated chitosan (PPP) hydrogel electrode was designed by freezing thawing method. The results show that PPP hydrogel has a good adsorption effect on uranium, and 200 mL of uranium tailings leachate is absorbed, and the treatment efficiency reaches 100 % within 15 min. PPP hydrogel can adapt to a wide range of pH conditions and exhibit excellent adsorption efficiency in the range of 3-9. At the same time, PPP hydrogel maintains an adsorption efficiency of over 85 % for 950 mg/L uranium solution. This lays the foundation for the practical application of PPP hydrogel. In addition, PPP hydrogel also exhibits good repeatability, after 7 cycles, the material still retains 95 % of its initial performance. The synergistic effect of various functional groups such as phosphate, hydroxyl, and ammonium in the material is the main mechanism of PPP's adsorption capacity for uranium. Furthermore, electrochemical adsorption method significantly enhances the adsorption performance of PPP hydrogel.


Assuntos
Quitosana , Urânio , Ácido Fítico , Álcool de Polivinil , Concentração de Íons de Hidrogênio , Hidrogéis , Adsorção
7.
Nat Nanotechnol ; 19(1): 51-57, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37783856

RESUMO

Printing technology for precise additive manufacturing at the nanoscale currently relies on two-photon lithography. Although this methodology can overcome the Rayleigh limit to achieve nanoscale structures, it still operates at too slow of a speed for large-scale practical applications. Here we show an extremely sensitive zirconium oxide hybrid-(2,4-bis(trichloromethyl)-6-(4-methoxystyryl)-1,3,5-triazine) (ZrO2-BTMST) photoresist system that can achieve a printing speed of 7.77 m s-1, which is between three and five orders of magnitude faster than conventional polymer-based photoresists. We build a polygon laser scanner-based two-photon lithography machine with a linear stepping speed approaching 10 m s-1. Using the ZrO2-BTMST photoresist, we fabricate a square raster with an area of 1 cm2 in ~33 min. Furthermore, the extremely small chemical components of the ZrO2-BTMST photoresist enable high-precision patterning, leading to a line width as small as 38 nm. Calculations assisted by characterizations reveal that the unusual sensitivity arises from an efficient light-induced polarity change of the ZrO2 hybrid. We envisage that the exceptional sensitivity of our organic-inorganic hybrid photoresist may lead to a viable large-scale additive manufacturing nanofabrication technology.

8.
J Asian Nat Prod Res ; 26(2): 189-194, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37882670

RESUMO

Two new baccharane triterpenes, 17,24-epoxy-23-en-baccharan-3-one (1) and 17,24(S)-epoxy-25-en-21-hydroxy-baccharan-3-one (2) were isolated from Rhus chinensis Mill. The structures were established on the basis of UV, IR, HR-ESI-MS, 1D and 2D NMR spectroscopy and X-ray diffraction analysis.


Assuntos
Rhus , Triterpenos , Triterpenos Pentacíclicos , Rhus/química , Triterpenos/farmacologia , Triterpenos/química , Extratos Vegetais , Espectroscopia de Ressonância Magnética , Estrutura Molecular
9.
Int J Biol Macromol ; 258(Pt 1): 128751, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38101661

RESUMO

A novel polyvinyl alcohol-carbon nanotube containing an imidazolyl ionic liquid/chitosan composite hydrogel (termed CBCS) was prepared for highly selective uranium adsorption from seawater. The results show that CBCS has good adsorption properties for uranium within the pH range of 5.0-8.0. Kinetics and thermodynamics experiments show that the theoretical maximum adsorption capacity of CBCS to U(VI) is 496.049 mg/g (288 K, pH = 6.0), indicating a spontaneous exothermic reaction. Mechanism analysis shows that the hydroxyl group, amino group, and CN bond on the surface of CBCS directly participate in uranium adsorption and that the dense pores on the surface of CBCS play an important role in uranium adsorption. The competitive adsorption experiment shows that CBCS has excellent uranium adsorption selectivity. In addition, CBCS exhibits good reusability. After five adsorption-desorption cycles, the uranium adsorption rate of CBCS can still reach >98 %. Hence, CBCS has excellent potential for uranium extraction from seawater.


Assuntos
Quitosana , Líquidos Iônicos , Nanotubos de Carbono , Urânio , Álcool de Polivinil , Urânio/química , Quitosana/química , Hidrogéis/química , Água do Mar/química , Adsorção , Cinética , Concentração de Íons de Hidrogênio
10.
Am J Transl Res ; 15(9): 5683-5690, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854201

RESUMO

OBJECTIVE: To investigate the efficacy of ZM suture combined with early functional exercise in repairing flexor tendons and its impact on finger function recovery in patients. METHODS: A retrospective analysis was conducted on 60 patients who sought medical treatment at the Orthopedics Hospital of Xingtai City from August 2019 to August 2022. Among them, 29 patients treated with the modified Kessler suture technique were assigned to the control group, while 31 patients treated with ZM suture technique were assigned to the observation group. Both groups of patients underwent early functional exercise after surgery and were followed up regularly for 6 months. Finger function, grip strength, pinch strength at 6 months after operation, upper limb function before and after treatment, visual analog pain scale (VAS) at 1 and 2 weeks postoperatively, quality of life, and incidence of complications were compared between the two groups. The risk factors affecting the prognosis of patients were analyzed. RESULTS: At 6 months postoperatively, the observation group showed significantly better finger function, grip strength and grip strength ratio, and upper limb function compared to the control group (all P<0.05). The observation group had significantly lower VAS scores at 1 and 2 weeks postoperatively and a significantly lower incidence of complications compared to the control group, while their quality of life was significantly better than that of the control group (all P<0.05). The choice of treatment method is an independent risk factor affecting the prognosis of patients (P<0.05). CONCLUSION: The ZM suture technique combined with early functional exercise has significant efficacy in repairing flexor tendons, effectively promoting finger function recovery in patients. It is also associated with a high level of safety and warrants clinical application and promotion.

11.
Environ Res ; 239(Pt 1): 117286, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37797668

RESUMO

In the field of environmental science, traditional methods for predicting PM2.5 concentrations primarily focus on singular temporal or spatial dimensions. This approach presents certain limitations when it comes to deeply mining the joint influence of multiple monitoring sites and their inherent connections with meteorological factors. To address this issue, we introduce an innovative deep-learning-based multi-graph model using Beijing as the study case. This model consists of two key modules: firstly, the 'Meteorological Factor Spatio-Temporal Feature Extraction Module'. This module deeply integrates spatio-temporal features of hourly meteorological data by employing Graph Convolutional Networks (GCN) and Long Short-Term Memory (LSTM) for spatial and temporal encoding respectively. Subsequently, through an attention mechanism, it retrieves a feature tensor associated with air pollutants. Secondly, these features are amalgamated with PM2.5 concentration values, allowing the 'PM2.5 Concentration Prediction Module' to predict with enhanced accuracy the joint influence across multiple monitoring sites. Our model exhibits significant advantages over traditional methods in processing the joint impact of multiple sites and their associated meteorological factors. By providing new perspectives and tools for the in-depth understanding of urban air pollutant distribution and optimization of air quality management, this model propels us towards a more comprehensive approach in tackling air pollution issues.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Aprendizado Profundo , Conceitos Meteorológicos , Material Particulado
12.
Medicine (Baltimore) ; 102(28): e34347, 2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37443492

RESUMO

The change in axial tibial rotation after uniplane medial open-wedge high tibial osteotomy (uniplane OWHTO) and its relevant influence factor is not known. Therefore, the aim of this study was to evaluate the change in axial tibial rotation after uniplane OWHTO, and the factors affecting tibia rotational change were analyzed. Between January 2022 and April 2022, the study was retrospectively conducted on genu varum patients who underwent uniplane OWHTO. In the weight-bearing anteroposterior long leg view, the hip-knee-ankle angle and medial proximal tibial angle (MPTA) were evaluated. The posterior tibial slope were measured from the lateral view. A CT scan of the knee joint was performed to evaluate the distal tibial rotation angle (TRA), femorotibial rotation angle and tibial tuberosity-trochlear groove distance. In addition, the foot morphology was assessed by the ankle deformity angle and ankle rotation angle using an angle measuring instrument. All parameters were measured preoperatively and 14 days after surgery. The mean change in hip-knee-ankle, MPTA was 10.5°±2.9°, 8.8°±2.6°. The mean preoperative and postoperative TRA were 25.1°±6.9° and 22.2°±6.2° respectively (P = .007). Thus, the mean ∆TRA was -3.0°±3.4° (IR) with a range of -9.6° to +2.8° after surgery. No significant differences were found in the femorotibial rotation angle and tibial tuberosity-trochlear groove distance before and after surgery (P > .05). The postoperative ankle rotation angle and ankle deformity angle changed significantly compared with preoperative values (P < .001). In the multiple regression analysis, ∆MPTA was the only predictor of distal tibial rotation (ß = 0.667, P = .003). The current study confirms an unintended internal rotation in the distal tibia following uniplane MOWHTO and the rotation in the distal tibia was influenced by the opening width. Surgeron should keep in mind to avoid the osteotomy complication leading to excessive rotation change during surgery.


Assuntos
Genu Varum , Osteoartrite do Joelho , Humanos , Genu Varum/diagnóstico por imagem , Genu Varum/cirurgia , Estudos Retrospectivos , Articulação do Joelho/diagnóstico por imagem , Articulação do Joelho/cirurgia , Osteotomia , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Osteoartrite do Joelho/diagnóstico por imagem , Osteoartrite do Joelho/cirurgia
13.
ACS Appl Mater Interfaces ; 15(25): 30870-30879, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37316963

RESUMO

Two-photon polymerization based direct laser writing (DLW) is an emerging micronano 3D fabrication technology wherein two-photon initiators (TPIs) are a key component in photoresists. Upon exposure to a femtosecond laser, TPIs can trigger the polymerization reaction, leading to the solidification of photoresists. In other words, TPIs directly determine the rate of polymerization, physicochemical properties of polymers, and even the photolithography feature size. However, they generally exhibit extremely poor solubility in photoresist systems, severely inhibiting their application in DLW. To break through this bottleneck, we propose a strategy to prepare TPIs as liquids via molecular design. The maximum weight fraction of the as-prepared liquid TPI in photoresist significantly increases to 2.0 wt %, which is several times higher than that of commercial 7-diethylamino-3-thenoylcoumarin (DETC). Meanwhile, this liquid TPI also exhibits an excellent absorption cross section (64 GM), allowing it to absorb femtosecond laser efficiently and generate abundant active species to initiate polymerization. Remarkably, the respective minimum feature sizes of line arrays and suspended lines are 47 and 20 nm, which are comparable to that of the-state-of-the-art electron beam lithography. Besides, the liquid TPI can be utilized to fabricate various high-quality 3D microstructures and manufacture large-area 2D devices at a considerable writing speed (1.045 m s-1). Therefore, the liquid TPI would be one of the promising initiators for micronano fabrication technology and pave the way for future development of DLW.

14.
Chemosphere ; 335: 139022, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37247676

RESUMO

The effect of oxygen on the reduction of uranyl and photocorrosion of CdS remains a pressing issue when CdS is used as a photocatalyst for the removal of uranyl in uranium-containing wastewater. In this study, composites (CdS/PCN) were prepared by designing N-deficient g-C3N4 composite with CdS for efficient photocatalytic reduction of uranyl under aerobic condition. Meanwhile, a series of characterizations of the CdS/PCN composites were carried out by XRD, FT-IR, XPS, EDS and UV-vis. Surprisingly, the CdS/PCN not only showed very high photocatalytic reduction activity for uranyl under aerobic condition, but also the photocorrosion of CdS by oxygen and h+ was inhibited. With a starting uranium (VI) concentration of 20 ppm, the uranium (VI) removal efficiency could reach 97.33% (dark: 30 min, light: 10 min). Interestingly, the removal efficiency was better in air condition than in pure nitrogen or 30% oxygen atmosphere, i.e. a proper amount of oxygen has accelerated the reduction reaction, while excess oxygen weakened the reduction. Finally, a new mechanism of reduction of uranyl by CdS/PCN photocatalyst was given under aerobic condit ions. This work presents a novel strategy for reduction of U(VI) by photocatalysis and the inhibition of photocorrosion of photocatalysts under aerobic conditions.


Assuntos
Urânio , Urânio/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Catálise , Luz , Águas Residuárias
15.
Ecol Appl ; 33(5): e2858, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37084186

RESUMO

Emissions of methane (CH4 ) and nitrous oxide (N2 O) from soils to the atmosphere can offset the benefits of carbon sequestration for climate change mitigation. While past study has suggested that both CH4 and N2 O emissions from tidal freshwater forested wetlands (TFFW) are generally low, the impacts of coastal droughts and drought-induced saltwater intrusion on CH4 and N2 O emissions remain unclear. In this study, a process-driven biogeochemistry model, Tidal Freshwater Wetland DeNitrification-DeComposition (TFW-DNDC), was applied to examine the responses of CH4 and N2 O emissions to episodic drought-induced saltwater intrusion in TFFW along the Waccamaw River and Savannah River, USA. These sites encompass landscape gradients of both surface and porewater salinity as influenced by Atlantic Ocean tides superimposed on periodic droughts. Surprisingly, CH4 and N2 O emission responsiveness to coastal droughts and drought-induced saltwater intrusion varied greatly between river systems and among local geomorphologic settings. This reflected the complexity of wetland CH4 and N2 O emissions and suggests that simple linkages to salinity may not always be relevant, as non-linear relationships dominated our simulations. Along the Savannah River, N2 O emissions in the moderate-oligohaline tidal forest site tended to increase dramatically under the drought condition, while CH4 emission decreased. For the Waccamaw River, emissions of both CH4 and N2 O in the moderate-oligohaline tidal forest site tended to decrease under the drought condition, but the capacity of the moderate-oligohaline tidal forest to serve as a carbon sink was substantially reduced due to significant declines in net primary productivity and soil organic carbon sequestration rates as salinity killed the dominant freshwater vegetation. These changes in fluxes of CH4 and N2 O reflect crucial synergistic effects of soil salinity and water level on C and N dynamics in TFFW due to drought-induced seawater intrusion.


Assuntos
Óxido Nitroso , Áreas Alagadas , Solo/química , Metano , Carbono , Florestas , Dióxido de Carbono/análise
16.
ACS Appl Mater Interfaces ; 15(15): 19349-19361, 2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37036936

RESUMO

To address the shortcomings of traditional filler-based wearable hydrogels, a new type of nanochannel hydrogel sensor is fabricated in this work through a combination of the unique structure of electrospun fiber textile and the properties of a double network hydrogel. Unlike the traditional Ti3C2Tx MXene-based hydrogels, the continuously distributed Ti3C2Tx MXene in the nanochannels of the hydrogel forms a tightly interconnected structure similar to the neuron network. As a result, they have more free space to flip and perform micromovements, which allows one to significantly increase the electrical conductivity and sensitivity of the hydrogel. According to the findings, the Ti3C2Tx MXene nanochannel hydrogel has excellent mechanical properties as well as self-adhesion and antifreezing characteristics. The hydrogel sensor successfully detects different human motions and physiological signals (e.g., low pulse signals) with high stability and sensitivity. Therefore, the proposed Ti3C2Tx MXene-based hydrogel with a unique structure and properties is very promising in the field of flexible wearable devices.


Assuntos
Hidrogéis , Dispositivos Eletrônicos Vestíveis , Humanos , Cimentos de Resina , Condutividade Elétrica
17.
J Asian Nat Prod Res ; 25(11): 1038-1043, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37071690

RESUMO

One new sesquiterpene, (6S,7R,11S)-13-carboxy-1(10)-en-dihydroartemisinic acid (1), together with three known sesquiterpenes, ainsliaea acid B (2), mongolicumin B (3), and 11ß,13-dihydroxydeacetylmatricarin (4) were isolated from Taraxacum mongolicum Hand.-Mazz. The structures were established on the basis of UV, IR, HR-ESI-MS, 1D and 2D NMR spectroscopy, ECD spectroscopy, and X-ray diffraction analysis. Compound 1 was found to have potential anti-inflammatory activity and could reduce LPS-induced NO levels in murine macrophage, with inhibitory rate of 37%.


Assuntos
Asteraceae , Sesquiterpenos , Taraxacum , Animais , Camundongos , Taraxacum/química , Espectroscopia de Ressonância Magnética , Macrófagos , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Estrutura Molecular
18.
J Exp Bot ; 74(14): 4189-4207, 2023 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-37086216

RESUMO

Apple necrotic mosaic virus (ApNMV) is associated with apple mosaic disease in China. However, the mechanisms of ApNMV infection, as well as host defence against the virus, are still poorly understood. Mitochondrial ATP synthase plays a fundamental role in the regulation of plant growth and development. However, mitochondrial ATP synthase function in response to virus infection remains to be defined. In the present study, a yeast two-hybrid (Y2H) screening revealed that the apple mitochondrial ATP synthase oligomycin sensitivity-conferring protein (OSCP) subunit (MdATPO) interacts with ApNMV coat protein (CP). It was further verified that overexpression of MdATPO in Nicotiana benthamiana inhibited viral accumulation. In contrast, silencing of NbATPO facilitated viral accumulation, indicating that ATPO plays a defensive role during ApNMV infection. Further investigation demonstrated that ApNMV infection accelerated abscisic acid (ABA) accumulation, and ABA negatively regulated ATPO transcription, which was related to the ability of ABA insensitive 5 (ABI5) to bind to the ABA-responsive elements (ABREs) of the ATPO promoter. Taken together, our results indicated that transcription factor ABI5 negatively regulated ATPO transcription by directly binding to its promoter, leading to the susceptibility of apple and N. benthamiana to ApNMV infection. The current study facilitates a comprehensive understanding of the intricate responses of the host to ApNMV infection.


Assuntos
Proteínas de Arabidopsis , ATPases Mitocondriais Próton-Translocadoras , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Regulação para Baixo , Fatores de Transcrição/metabolismo , Ácido Abscísico/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Proteínas de Arabidopsis/metabolismo
19.
Int J Biol Macromol ; 238: 124074, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-36934816

RESUMO

A novel chitosan-based porous composite adsorbent with multifunctional groups, such as phosphoric acid, amidoxime, and quaternary ammonium groups, was prepared to improve the adsorption rate and competitive uranium­vanadium adsorption of amidoxime group adsorbents. The maximum uranium adsorption capacity of PACNC was 962.226 mg g-1 at 308 K and pH = 7. The maximum adsorption rate constant of PACNC for uranium was 2.83E-2 g mg-1 min-1, which is 2.38 times that of ACNC (1.19E-2 g mg-1 min-1). Moreover, the adsorption equilibrium time was shortened from 300 (ACNC) to 50 (PACNC) min. In simulated and real seawater, the Kd and adsorption capacity of PACNC for uranium were approximately 8 and 6.62 times those for vanadium, respectively. These results suggest that phosphorylation significantly improved the competitive adsorption of uranium­vanadium and uranium adsorption rate. PACNC also exhibited good recycling performance and maintained stable adsorption capacity after five cycles. DFT calculations were used to analyze and calculate the possible co-complex structure of PACNC and uranium. The binding structure of phosphate and amidoxime is the most stable, and its synergistic effect effectively improves the competitive adsorption of uranium-vanadium of amidoxime. All the results demonstrated that PACNC has substantial application potential for uranium extraction from seawater.


Assuntos
Quitosana , Urânio , Urânio/química , Quitosana/química , Adsorção , Fosforilação , Vanádio , Água do Mar/química
20.
J Gen Virol ; 104(2)2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36802334

RESUMO

The coat protein (CP) of plant viruses generally has multiple functions involving infection, replication, movement and pathogenicity. Functions of the CP of prunus necrotic ringspot virus (PNRSV), the causal agent of several threatening diseases of Prunus fruit trees, are poorly studied. Previously, we identified a novel virus in apple, apple necrotic mosaic virus (ApNMV), which is phylogenetically related to PNRSV and probably associated with apple mosaic disease in China. Full-length cDNA clones of PNRSV and ApNMV were constructed, and both are infectious in cucumber (Cucumis sativus L.), an experimental host. PNRSV exhibited higher systemic infection efficiency with more severe symptoms than ApNMV. Reassortment analysis of genomic RNA segments 1-3 found that RNA3 of PNRSV could enhance the long-distance movement of an ApNMV chimaera in cucumber, indicating the association of RNA3 of PNRSV with viral long-distance movement. Deletion mutagenesis of the PNRSV CP showed that the basic motif from amino acids 38 to 47 was crucial for the CP to maintain the systemic movement of PNRSV. Moreover, we found that arginine residues 41, 43 and 47 codetermine viral long-distance movement. The findings demonstrate that the CP of PNRSV is required for long-distance movement in cucumber, which expands the functions of ilarvirus CPs in systemic infection. For the first time, we identified involvement of Ilarvirus CP protein during long-distance movement.


Assuntos
Ilarvirus , Prunus , Ilarvirus/genética , Ilarvirus/metabolismo , RNA Viral/metabolismo , Prunus/genética , China
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