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1.
Water Res ; 265: 122320, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39197392

RESUMEN

The efficient capture of uranium from wastewater is crucial for environmental remediation and the sustainable development of nuclear energy, yet it poses considerable challenges. In this study, amphiphilic ionic covalent organic framework intercalated into graphene oxide (GO) nanosheets functionalized with polyethyleneimine (PEI) were used to construct hybrid membranes with ultrafast uranium adsorption. These hybrid membranes achieved equilibrium in just 10 min and the adsorption capacity was as high as 358.8 mg g-1 at pH = 6. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) analyses revealed that the strong interaction between sulfonic acid groups and uranyl ions was the primary reason for the high adsorption capacity and selectivity. The extended transition state and natural orbitals for chemical valence (ETS-NOCV) analysis revealed that the interaction between the 7 s and 5f orbitals of uranyl and the 2p orbitals of S and O in the sulfonate was the primary reason for the strong interaction between the sulfonate and the uranyl ion. This research presents an effective method for the rapid extraction of uranium from wastewater.


Asunto(s)
Grafito , Uranio , Aguas Residuales , Uranio/química , Grafito/química , Aguas Residuales/química , Adsorción , Espectroscopía de Fotoelectrones , Membranas Artificiales , Estructuras Metalorgánicas/química , Contaminantes Radiactivos del Agua/química
2.
J Colloid Interface Sci ; 677(Pt A): 435-445, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39098277

RESUMEN

Extraction uranium (VI) (U(VI)) from wastewater and seawater is highly important for environmental protection and life safety, but it remains a great challenge. In this work, the growth of the zeolitic imidazolate framework-8 (ZIF-8) nanoparticles on the tannic acid (TA)-3-aminopropyltriethoxysilane (APTES) modified PVDF (TAP) membrane was designed to obtain an excellent U(VI) adsorbent. The zeolite imidazolate framework composite membrane (TAPP-ZIF-60) was prepared through polyethyleneimine (PEI) bridging strategy and temperature regulation strategy in solvothermal method. The coordination bond between PEI and ZIF-8 and the covalent bond between PEI and TAP are essential in forming stable composite membrane. TAPP-ZIF with different properties was synthesized through a temperature regulation process and the TAPP-ZIF prepared at 60 °C has the uniform morphology and good performance. The adsorption capacity of TAPP-ZIF-60 is 153.68 mg/g (C0 = 95.01 mg/L and pH = 8.0) and water permeability is 5459 L m-2 h-1 bar-1. After ten adsorption-desorption cycles, it is proved that TAPP-ZIF-60 has good repeatability and stability. In addition, the TAPP-ZIF-60 composites membrane has a good inhibitory effect on Staphylococcus aureus and Escherichia coli. X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) analysis reveal that the coordination between TAPP-ZIF-60 and uranyl ions is the primary factor contributing to the high adsorption capacity.

3.
J Neural Eng ; 21(4)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39029496

RESUMEN

Objective.Brain switches provide a tangible solution to asynchronized brain-computer interface, which decodes user intention without a pre-programmed structure. However, most brain switches based on electroencephalography signals have high false positive rates (FPRs), resulting in less practicality. This research aims to improve the operating mode and usability of the brain switch.Approach.Here, we propose a novel virtual physical model-based brain switch that leverages periodic active modulation. An optimization problem of minimizing the triggering time subject to a required FPR is formulated, numerical and analytical approximate solutions are obtained based on the model.Main results.Our motor imagery (MI)-based brain switch can reach 0.8FP/h FPR with a median triggering time of 58 s. We evaluated the proposed brain switch during online device control, and their average FPRs substantially outperformed the conventional brain switches in the literature. We further improved the proposed brain switch with the Common Spatial Pattern (CSP) and optimization method. An average FPR of 0.3 FPs/h was obtained for the MI-CSP-based brain switch, and the average triggering time improved to 21.6 s.Significance.This study provides a new approach that could significantly reduce the brain switch's FPR to less than 1 Fps/h, which was less than 10% of the FPR (decreasing by more than a magnitude of order) by other endogenous methods, and the reaction time was comparable to the state-of-the-art approaches. This represents a significant advancement over the current non-invasive asynchronous BCI and will open widespread avenues for translating BCI towards clinical applications.


Asunto(s)
Interfaces Cerebro-Computador , Electroencefalografía , Imaginación , Humanos , Imaginación/fisiología , Electroencefalografía/métodos , Encéfalo/fisiología , Modelos Neurológicos , Movimiento/fisiología
4.
Chem Biodivers ; 21(6): e202400519, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38576052

RESUMEN

One new highly degraded steroid, namely 21-nor-4-ene-chaxine A (1) furnishing a 5/6/5-tricyclic, along with one known related analogue (2), were isolated from the South China Sea sponge Spongia officinalis. Their structures including absolute configurations were established by extensive spectroscopic data analysis, TDDFT-ECD calculation, and comparison with the spectral data previously reported in the literature. Compound 1 represent the new member of incisterols family with a highly degradation in ring B. In vitro bioassays revealed compound 2 exhibited significant anti-microglial inflammatory effect on lipopolysaccharide (LPS)-induced inflammation in BV-2 microglial cells.


Asunto(s)
Antiinflamatorios , Lipopolisacáridos , Poríferos , Esteroides , Animales , Poríferos/química , Esteroides/química , Esteroides/aislamiento & purificación , Esteroides/farmacología , Lipopolisacáridos/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Ratones , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , China , Microglía/efectos de los fármacos , Microglía/metabolismo , Microglía/citología , Línea Celular , Conformación Molecular , Estructura Molecular
5.
Phytochemistry ; 222: 114110, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38663824

RESUMEN

Molecular networking strategy-based prioritization of the isolation of the rarely studied soft coral Sinularia tumulosa yielded 14 sesquiterpenes. These isolated constituents consisted of nine different types of carbon frameworks, namely asteriscane, humulane, capillosane, seco-asteriscane, guaiane, dumortane, cadinane, farnesane, and benzofarnesane. Among them, situmulosaols A-C (1, 3 and 4) were previously undescribed ones, whose structures with absolute configurations were established by the combination of extensive spectral data analyses, quantum mechanical-nuclear magnetic resonance and time-dependent density functional theory electronic circular dichroism calculations, the Snatzke's method, and the modified Mosher's method. Notably, situmulosaol C (4) was the second member of capillosane-type sesquiterpenes. The plausible biogenetic relationships of these skeletally different sesquiterpenes were proposed. All sesquiterpenoids were evaluated for their antibacterial, cytotoxic and anti-inflammatory effects. The bioassay results showed compound 14 exhibited significant antibacterial activities against a variety of fish and human pathogenic bacteria with MIC90 values ranging from 3.6 to 33.8 µg/mL. Moreover, moderate cytotoxic effects against HEL cells for components 13 and 14 and moderate inhibitory effect on lipopolysaccharide-induced inflammatory responses in RAW264.7 cells for substance 13 were also observed.


Asunto(s)
Antozoos , Sesquiterpenos , Antozoos/química , Sesquiterpenos/química , Sesquiterpenos/farmacología , Sesquiterpenos/aislamiento & purificación , Animales , Ratones , Estructura Molecular , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , China , Células RAW 264.7 , Pruebas de Sensibilidad Microbiana , Lipopolisacáridos/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Relación Estructura-Actividad , Humanos , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Teoría Funcional de la Densidad , Relación Dosis-Respuesta a Droga
6.
IEEE J Biomed Health Inform ; 28(5): 2769-2780, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38442053

RESUMEN

In code-modulated visual evoked potential (c-VEP) based BCI systems, flickering visual stimuli may result in visual fatigue. Thus, we introduced a discrete-interval binary sequence (DIBS) as visual stimulus modulation, with its power spectrum optimized to emphasize high-frequency components (40 Hz-60 Hz). 8 and 17 subjects participated, respectively, in offline and online experiments on a 4-target asynchronous c-VEP-based BCI system designed to realize a high positive predictive value (PPV), a low false positive rate (FPR) during idle states, and a high true positive rate (TPR) in control states, while minimizing visual fatigue level. Two visual stimuli modulations were introduced and compared: a maximum length sequence (m-sequence) and the high-frequency discrete-interval binary sequence (DIBS). The decoding algorithm was compared among the canonical correlation analysis (CCA), the task-related component analysis (TRCA), and two approaches of sub-band component weight calculation (the traditional method and the proportional method) for FBCCA and FBTRCA. In the online experiments, the average PPV, FPR and TPR achieved, respectively [Formula: see text], [Formula: see text], [Formula: see text] with m-sequence, while [Formula: see text], [Formula: see text] and [Formula: see text] with DIBS. Estimated by objective eye-related metrics and a subjective questionnaire, the visual fatigue in DIBS cases is significantly smaller than that in m-sequence cases. In this study, the feasibility of a novel modulation approach for visual fatigue reduction was proved in an asynchronous c-VEP system, while maintaining comparable performance to existing methods, which provides further insights towards enhancing this field's long-term viability and user-friendliness.


Asunto(s)
Algoritmos , Interfaces Cerebro-Computador , Electroencefalografía , Potenciales Evocados Visuales , Procesamiento de Señales Asistido por Computador , Humanos , Potenciales Evocados Visuales/fisiología , Masculino , Adulto , Femenino , Adulto Joven , Electroencefalografía/métodos , Estimulación Luminosa/métodos , Astenopía/fisiopatología
7.
Int J Biol Macromol ; 266(Pt 2): 130996, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38531521

RESUMEN

Metal-organic frameworks (MOF)-polymer hybrid hydrogel solves the processable forming of MOF powder and energy consumption of uranium extraction. However, the hybrid hydrogel by conventional synthesis methods inevitably lead to MOF agglomeration, poor filler-polymer interfacial compatibility and slowly adsorption. Herein, we designed that ZIF-67 was implanted into the carboxymethyl cellulose/polyacrylamide (CMC/PAM) by network-repairing strategy. The carboxyl and amino groups on the surface of CMC/PAM drive the uniform growth of ZIF-67 inside the CMC/PAM, which form an array of oriented and penetrating microchannels through coordination bonds. Our strategy eliminate the ZIF-67 agglomeration, increase the interfacial compatibility between MOF and polymer. The method also improve the free and fast diffusion of uranium in CMC/PAM/ZIF-67 hydrogel. According to the experimental, these enhancements synergistically enabled the CMC/PAM/ZIF-67 have a maximum adsorption capacity of 952 mg g-1. The adsorption process of CMC/PAM/ZIF-67 fits well with pseudo-second-order model and Langmuir isotherm. Meanwhile, the CMC/PAM/ZIF-67 maintain a high removal rate (87.3 %) and chemical stability even during ten adsorption-desorption cycles. It is worth noting that the adsorption amount of CMC/PAM/ZIF-67 in real seawater is 9.95 mg g-1 after 20 days, which is an ideal candidate adsorbent for uranium extraction from seawater.


Asunto(s)
Resinas Acrílicas , Carboximetilcelulosa de Sodio , Estructuras Metalorgánicas , Agua de Mar , Uranio , Uranio/química , Uranio/aislamiento & purificación , Adsorción , Resinas Acrílicas/química , Carboximetilcelulosa de Sodio/química , Estructuras Metalorgánicas/química , Agua de Mar/química , Hidrogeles/química , Cinética , Purificación del Agua/métodos , Contaminantes Radiactivos del Agua/aislamiento & purificación , Contaminantes Radiactivos del Agua/química
8.
Dalton Trans ; 53(7): 2937-2948, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38240359

RESUMEN

The commercial application of lithium-sulfur (Li-S) batteries is limited by the inherent defects of poor conductivity of sulfur and the shuttling effect of polysulfides. To overcome these limitations, a modified layer comprising a porous network PVDF-PMMA skeleton and Ketjen black (KB) carbon nanoparticles was coated on the polyethylene (PE) separator using the phase inversion method. The PVDF-PMMA-KB (PPK) composite layer with a structure abundant in mesopores can effectively limit the shuttling effect of polysulfides via a physical barrier and adsorption. Moreover, the utilization of active substances substantially increased as the KB carbon nanoparticles could provide additional reaction sites for activating inactive polysulfides and depositing lithium sulfide. The electrochemical properties of the Li-S battery were considerably enhanced using the modified separator with a PPK layer, which was reflected in the higher rate capability and longer cycling life. The cell with a modified separator delivered a specific capacity of 723 mA h g-1 at 1 C, and the capacity retention reached 73.3% after 400 cycles with a low decay rate of 0.223% per cycle. This work provides a novel preparation method for a modified layer on the separator and promotes the large-scale application of Li-S batteries.

9.
Mar Drugs ; 22(1)2024 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-38276652

RESUMEN

Five new cembrane-type diterpenes, lobocalines A-E (1-5), and four new steroids, lobocaloids A-D (9-12), along with six known related compounds (6-8 and 13-15) were isolated from the Yalong Bay soft coral Lobophytum catalai Tixier-Durivault. The structures of the new compounds were elucidated by extensive spectroscopic analysis, NMR calculation with DP4+ analysis, time-dependent density functional theory-electronic circular dichroism (TDDFT-ECD) calculations, X-ray diffraction analyses and comparison with the reported spectroscopic data of known compounds. Further, with the aid of X-ray diffraction analysis, the structure of lobocrasol B (15) was firmly revised as 15a. In in vitro bioassays, compound 2 showed moderate antibacterial activities against fish pathogenic bacteria Streptococcus parauberis KSP28 and Phoyobacterium damselae FP2244 with minimum inhibitory concentration (MIC) values of 8.7 and 17.3 µg/mL, respectively. All the steroids exhibited antibacterial activities against the S. parauberis KSP28 with MIC values ranging from 12.3 to 53.6 µg/mL. Compounds 2, 7 and 14 have remarkable inhibitory effects on the hemolysin production of Staphylococcus aureus, while compounds 8-12 have medium inhibitory effects on the pyocyanin production in Pseudomonas aeruginosa.


Asunto(s)
Antozoos , Diterpenos , Animales , Esteroides/farmacología , Antibacterianos/farmacología , Espectroscopía de Resonancia Magnética , Antozoos/química , Diterpenos/química , China , Estructura Molecular
10.
Abdom Radiol (NY) ; 49(3): 908-918, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37957372

RESUMEN

PURPOSE: Data on medium- and long-term efficacy and safety of Transjugular intrahepatic portosystemic shunt (TIPS) using Viatorr stents in Chinese patients are limited. This study aimed to evaluate the 5-year mortality and the incidence of overt hepatic encephalopathy (OHE) after Viatorr stent insertion, and construct a model to predict post-TIPS OHE preoperatively. METHODS: One hundred thirty-two patients undergoing Viatorr stent insertion in our institution between August 2016 and December 2019 were included, and randomly divided into training and validation cohort at a 70/30 ratio. Patients were followed up until death or the end date of follow-up (December 31st, 2021). The primary end point was all-cause mortality, and the secondary end points were OHE, variceal rebleeding, recurrent ascites and shunt dysfunction. RESULTS: The 1-, 2-, 3-, 4- and 5-year cumulative survival rates were 92.4%, 87.9%, 85.3%, 80.2% and 80.2%, respectively. Post-TIPS OHE and Child-Pugh grade were independent prognostic factors. The rates of variceal rebleeding, recurrent ascites, shunt dysfunction and post-TIPS OHE were 9.1%, 14.3%, 5.3% and 28.0%, respectively. The variables of nomogram predicting post-TIPS OHE included age, diabetes and ascites grade. The area under time-dependent receiver operation characteristic (ROC) curve (AUC) in training and validation cohort were 0.806 and 0.751, respectively. The decision curve analysis (DCA) showed good net benefit both in training and validation cohort. CONCLUSION: Post-TIPS OHE and Child-Pugh grade are independent prognostic factors for early mortality in cirrhosis patients, thus we construct a simple and convenient prediction model for post-TIPS OHE to identify high-risk patients preoperatively.


Asunto(s)
Encefalopatía Hepática , Derivación Portosistémica Intrahepática Transyugular , Humanos , Encefalopatía Hepática/epidemiología , Encefalopatía Hepática/etiología , Estudios Retrospectivos , Ascitis/complicaciones , Recurrencia Local de Neoplasia , Cirrosis Hepática/complicaciones , Cirrosis Hepática/cirugía , Resultado del Tratamiento
11.
J Nat Prod ; 87(1): 121-131, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38151459

RESUMEN

A phytochemical investigation of an East China Sea collection of the brown alga Dictyota coriacea has led to the isolation of four novel nitrogen-containing crenulide diterpenoids, named coriaceumins A-D (1-4), two rare nitrogenous xenicane diterpenoids, dictyolactams C (5) and D (6), and one known crenulide diterpenoid, hydroxycrenulide (7). The structures of the new compounds were elucidated by detailed spectroscopic data analyses, including HRESIMS and 1D/2D NMR. The absolute configurations were determined by a comparison of the experimental ECD spectra with the spectra computed by DFT-based quantum chemical calculations. Coriaceumins A-D (1-4) represent the first examples of nitrogen-containing crenulide diterpenoids. In a bioassay, compounds 2, 3, 5, and 7 were found to exhibit different levels of inhibitory effects against protein tyrosine phosphatase 1B (PTP1B) with IC50 values ranging from 7.3 to 19 µM. In addition, the primary structure-activity relationships of all the isolates were summarized.


Asunto(s)
Diterpenos , Phaeophyceae , Estructura Molecular , Espectroscopía de Resonancia Magnética , Diterpenos/farmacología , Diterpenos/química , China
12.
Phytochemistry ; 219: 113960, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38159620

RESUMEN

The chemical investigation on the soft coral Sinularia brassica collected off Xuwen Country, Guangdong Province, China, has resulted in the isolation and characterization of three uncommon cycloamphilectane-type diterpenoids, namely sinucycloamtin A-C (1-3), along with two known analogues (5 and 6). In addition, compounds 2 and 3 were hydrolyzed and their hydrolytic derivative sinucycloamtin D (4) was obtained. The structures of these previously undescribed compounds were established on the basis of extensive spectroscopic analysis, X-ray diffraction analysis, chemical conversion, as well as the comparison with the literature reported data. Compounds 1-3 represented the first examples of benzene-containing cycloamphilectane-type diterpenoids isolated from soft coral of genus Sinularia. In the in vitro bioassays, all the isolated and derived diterpenoids exhibited significant antibacterial activities against the fish pathogenic bacteria Phoyobacterium damselae FP2244 and Streptococcus parauberis SPOF3K with MIC90 values ranging from 3.7 to 9.1 µM.


Asunto(s)
Antozoos , Brassica , Diterpenos , Animales , Estructura Molecular , Antozoos/química , Diterpenos/química , China
13.
Phys Rev Lett ; 131(13): 136101, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37832014

RESUMEN

Twinning is profuse in bcc transition metals (TMs) except bulk W and Mo. However, W and Mo nanocrystals surprisingly exhibit twinning during room temperature compression, which is completely unexpected as established nucleation mechanisms are not viable in them. Here, we reveal the physical origin of deformation twinning in W and Mo. We employ density functional theory (DFT) and a reduced-constraint slip method to compute the stress-dependent generalized stacking fault enthalpy (GSFH), the thermodynamic quantity to be minimized under constant loading. The simple slipped structures and GSFH lines show that compressive stresses stabilize a two-layer twin embryo, which can grow rapidly via twinning disconnections with negligible energy barriers. Direct atomistic simulations unveil the explicit twinning path in agreement with the DFT GSFH lines. Twinning is thus the preferred deformation mechanism in W and Mo when shear stresses are coupled with high compressive stresses. Furthermore, twinnability can be related to the elastic constants of a stacking fault phase (SFP). The hcp phase may serve as a candidate SFP for the {112}⟨1[over ¯]1[over ¯]1⟩ twinning system in bcc TMs and alloys, which is coincident with the {111}⟨112[over ¯]⟩ twinning in fcc structures.

14.
J Neural Eng ; 20(6)2023 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-37816342

RESUMEN

Objective.Decoding different types of movements noninvasively from electroencephalography (EEG) is an essential topic in neural engineering, especially in brain-computer interface. Although the widely used sensorimotor rhythm (SMR) is efficient in limb decoding, it lacks efficacy in decoding movement frequencies. Accumulating evidence supports the notion that the movement frequency is encoded in the steady-state movement-related rhythm (SSMRR). Our study has two primary objectives: firstly, to investigate the spatial-spectral representation of SSMRR in EEG during voluntary movements; secondly, to assess whether movement frequencies and limbs can be effectively decoded based on SSMRR.Approach.To comprehensively examine the representation of SSMRR, we investigated the frequency characteristics and spatial patterns associated with various rhythmic finger movements. Coherence analysis was performed between the sensor or source domain EEG and finger movements recorded by data gloves. A fusion model based on spectral SNR features and filter-bank common spatial pattern features was utilized to decode movement frequencies and limbs.Main results.At the group-level, sensor domain, and source domain coherence maps demonstrated that the accurate movement frequency (f0) and its first harmonic (f1) were encoded in the contralateral motor cortex. For the four-class classification, including two movement frequencies for both hands, the decoding accuracies for externally paced and internally paced movements were 73.14 ± 15.86% and 66.30 ± 17.26% (averaged across ten subjects, chance levels at 31.05% and 30.96%). Notably, the average results of five subjects with the highest decoding accuracies reached 87.21 ± 7.44% and 80.44 ± 7.99%.Significance.Our results verified the EEG representation of SSMRR and proved that the movement frequency and limb could be effectively decoded based on spatial-spectral features extracted from SSMRR. We suggest that SSMRR can serve as a complement to SMR to expand the range of decodable movement types and the approaches of limb decoding.


Asunto(s)
Interfaces Cerebro-Computador , Extremidad Superior , Humanos , Electroencefalografía/métodos , Mano , Dedos , Movimiento
15.
Molecules ; 28(19)2023 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-37836735

RESUMEN

Three new cembranoids (1-3) and a new casbanoid (4), along with three known analogues (5-7), have been isolated from the soft coral Sinularia nanolobata collected off Ximao Island. The structures, including the absolute configurations of new compounds, were established using extensive spectroscopic data analysis, time-dependent density functional theory/electronic circular dichroism (TDDFT-ECD) calculations, and the comparison with spectroscopic data of known compounds. In the in vitro bioassay, compounds 1 and 5 exhibited moderate cytotoxic activities against human erythroleukemia (HEL) cell lines, with IC50 values of 37.1 and 42.4 µM, respectively.


Asunto(s)
Antozoos , Diterpenos , Animales , Humanos , Estructura Molecular , Antozoos/química , Línea Celular Tumoral , Diterpenos/farmacología , Diterpenos/química , China
16.
J Asian Nat Prod Res ; 25(10): 949-956, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37624873

RESUMEN

The detailed chemical investigations of the South China Sea soft corals Sinularia tumulosa and Sinularia depressa, yielded two new compounds, namely tumulosterol A (1) and 11'-hydroxy-α-tocopherylquinone (3), along with four related known ones (2, 5-7). Their structures were determined by extensive spectroscopic analysis and comparison with the spectral data previously reported in the literature. In bioassays, compound 1 displayed significant cytotoxic effects against H1975 and MDA-MB-231 cells with IC50 values of 6.0 and 6.3 µM, respectively. In addition, compound 3 exhibited interesting inhibitory effect on lipopolysaccharide (LPS)-induced inflammatory responses in RAW264.7 cells with IC50 value of 9.5 µM.


Asunto(s)
Antozoos , Antineoplásicos , Animales , Antiinflamatorios/farmacología , Bioensayo , China
17.
Mar Life Sci Technol ; 5(3): 373-386, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37637258

RESUMEN

Marine invertebrates serve as rich sources of secondary metabolites with intriguing chemical diversities and a wide spectrum of biological activities. Particularly, marine shell-less sacoglossan mollusks have attracted much attentions due to the fact that mollusks apply complex metabolites as chemical defense agents against to their predators. With the purpose of discovering bioactive secondary metabolites to develop marine-derived medicines from the South China Sea, we have conducted a chemical study on the photosynthetic mollusk Placobranchus ocellatus. As a result, seven new γ-pyrone polypropionates, namely ( ±)-ocellatuspyrone A (1), ( ±)-ocellatuspyrone B (2), and ocellatuspyrones C-G (5, 9-12), along with five known polypropionates, have been isolated and characterized from the South China Sea photosynthetic mollusk Placobranchus ocellatus. Extensive spectroscopic analysis, single crystal X-ray diffraction analysis, modified Mosher's method, ECD comparison, CD exciton chirality method, TDDFT-ECD calculation, and chemical conversion were used to determine the structures and absolute configurations of the new compounds and the stereochemistry of undefined known compounds 4, 6 and 7. All these isolated polypropionates were evaluated in bioassays for their biological activities, including antibacterial, neuroprotective effect, anti-inflammatory, PTP1B inhibitory, and antiviral activities. Compounds 7, 8 and 11 were found for the first time to show antibacterial activity against fish pathogenic bacteria Streptococcus parauberis (the main pathogen causing fish streptococcal infections and acute death) with MIC values of 35.8, 34.2, and 37.4 µg/mL, respectively, which might be potential novel antibacterial agents for the treatment of fish infectious diseases. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-023-00179-w.

18.
Ecotoxicol Environ Saf ; 263: 115212, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37418945

RESUMEN

Antimicrobial resistance has gained increasing attention, because of the awareness of its potential health risks. Strategies for the removal of antibiotic resistance genes (ARGs) are urgently required. In the present study, UV-LEDs at wavelength of 265 and 285 nm were integrated at five conditions, including single 265 nm UV-LED, single 285 nm UV-LED, and combined 265 nm and 285 nm UV-LED at different intensities, to remove tet A, cat 1, and amp C. The ARGs removal efficiency, gene behavior, and possible cellular mechanism were analyzed using real-time quantitative PCR, flow cytometry, and transmission electron microscopy (TEM). The 265 nm UV-LED is more effective than the 285 nm UV-LED and their combinations in terms of ARGs control, in which 1.91, 1.71, and 1.45 log were removed for tet A, cat 1, and amp C, respectively, at a UV dosage of 500 mJ/cm2. The intracellular gene leakage was detected in all five UV-LED experiment scenarios even when the cell membrane damage was insignificant with the highest increase of 0.69 log ARGs. ROS was generated during the irradiation, and the ROS was strongly negative correlated with intracellular ARGs, which could promote the degradation and removal of ARGs. This study provides a new insight of intracellular ARGs removal, because direct irradiation, ROS oxidation, and leakage to the extracellular serve as the three main pathways under high-dosage UV-LED irradiation. Further research should be focused on the mechanism and optimization of UV technology with 265 nm UV-LED for ARG control.


Asunto(s)
Genes Bacterianos , Purificación del Agua , Antibacterianos/farmacología , Especies Reactivas de Oxígeno , Aguas Residuales , Farmacorresistencia Microbiana/genética , Rayos Ultravioleta
19.
Adv Sci (Weinh) ; 10(25): e2301713, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37381645

RESUMEN

Conductive hydrogels exhibit high potential in the fields of wearable sensors, healthcare monitoring, and e-skins. However, it remains a huge challenge to integrate high elasticity, low hysteresis, and excellent stretch-ability in physical crosslinking hydrogels. This study reports the synthesis of polyacrylamide (PAM)-3-(trimethoxysilyl) propyl methacrylate-grafted super arborized silica nanoparticle (TSASN)-lithium chloride (LiCl) hydrogel sensors with high elasticity, low hysteresis, and excellent electrical conductivity. The introduction of TSASN enhances the mechanical strength and reversible resilience of the PAM-TSASN-LiCl hydrogels by chain entanglement and interfacial chemical bonding, and provides stress-transfer centers for external-force diffusion. These hydrogels show outstanding mechanical strength (a tensile stress of 80-120 kPa, elongation at break of 900-1400%, and dissipated energy of 0.8-9.6 kJ m-3 ), and can withstand multiple mechanical cycles. LiCl addition enables the PAM-TSASN-LiCl hydrogels to exhibit excellent electrical properties with an outstanding sensing performance (gauge factor = 4.5), with rapid response (210 ms) within a wide strain-sensing range (1-800%). These PAM-TSASN-LiCl hydrogel sensors can detect various human-body movements for prolonged durations of time, and generate stable and reliable output signals. The hydrogels fabricated with high stretch-ability, low hysteresis, and reversible resilience, can be used as flexible wearable sensors.

20.
Chem Biodivers ; 20(8): e202300821, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37376927

RESUMEN

Three new steroids, along with two known related analogs, were isolated from the Xisha Island soft coral Lobophytum sarcophytoides. The structures and absolute configurations of the new compounds were elucidated by extensive spectroscopic data analyses, time dependent density functional theory electronic circular dichroism calculation, and comparison with the spectral data previously reported in the literature. In in vitro bioassay, four compounds showed interesting suppressive effects on lipopolysaccharide (LPS) induced inflammation in BV-2 microglial cells at 10 µM level.


Asunto(s)
Antozoos , Diterpenos , Animales , Antozoos/química , Esteroides/farmacología , Esteroides/química , Antiinflamatorios/farmacología , China , Lipopolisacáridos/farmacología , Diterpenos/química , Estructura Molecular
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