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1.
Chem Biol Interact ; 394: 110987, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38574835

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are widely used synthetic chemicals that persist in the environment and bioaccumulate in animals and humans. There is growing evidence that PFAS exposure adversely impacts neurodevelopment and neurological health. Steroid 5α-reductase 1 (SRD5A1) plays a key role in neurosteroidogenesis by catalyzing the conversion of testosterone or pregnenolone to neuroactive steroids, which influence neural development, cognition, mood, and behavior. This study investigated the inhibitory strength and binding interactions of 18 PFAS on human and rat SRD5A1 activity using enzyme assays, molecular docking, and structure-activity relationship analysis. Results revealed that C9-C14 PFAS carboxylic acid at 100 µM significantly inhibited human SRD5A1, with IC50 values ranged from 10.99 µM (C11) to 105.01 µM (C14), and only one PFAS sulfonic acid (C8S) significantly inhibited human SRD5A1 activity, with IC50 value of 8.15 µM. For rat SRD5A1, C9-C14 PFAS inhibited rat SRD5A1, showing the similar trend, depending on carbon number of the carbon chain. PFAS inhibit human and rat SRD5A1 in a carbon chain length-dependent manner, with optimal inhibition around C11. Kinetic studies indicated PFAS acted through mixed inhibition. Molecular docking revealed PFAS bind to the domain between NADPH and testosterone binding site of both SRD5A1 enzymes. Inhibitory potency correlated with physicochemical properties like carbon number of the carbon chain. These findings suggest PFAS may disrupt neurosteroid synthesis and provide insight into structure-based inhibition of SRD5A1.

2.
PLoS Pathog ; 20(4): e1012141, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38626263

RESUMO

Kaposi's sarcoma-associated herpesvirus (KSHV) is a double-stranded DNA virus etiologically associated with multiple malignancies. Both latency and sporadic lytic reactivation contribute to KSHV-associated malignancies, however, the specific roles of many KSHV lytic gene products in KSHV replication remains elusive. In this study, we report that ablation of ORF55, a late gene encoding a tegument protein, does not impact KSHV lytic reactivation but significantly reduces the production of progeny virions. We found that cysteine 10 and 11 (C10 and C11) of pORF55 are palmitoylated, and the palmytoilation is essential for its Golgi localization and secondary envelope formation. Palmitoylation-defective pORF55 mutants are unstable and undergo proteasomal degradation. Notably, introduction of a putative Golgi localization sequence to these palmitoylation-defective pORF55 mutants restores Golgi localization and fully reinstates KSHV progeny virion production. Together, our study provides new insight into the critical role of pORF55 palmitoylation in KSHV progeny virion production and offers potential therapeutic targets for the treatment of related malignancies.

3.
J Steroid Biochem Mol Biol ; 240: 106510, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38508472

RESUMO

The objective of this study was to examine the effect of 11 organochlorine pesticides on human and rat 17ß-Hydroxysteroid dehydrogenase 1 (17ß-HSD1) in human placental and rat ovarian microsome and on estradiol production in BeWo cells. The results showed that the IC50 values for endosulfan, fenhexamid, chlordecone, and rhothane on human 17ß-HSD1 were 21.37, 73.25, 92.80, and 117.69 µM. Kinetic analysis revealed that endosulfan acts as a competitive inhibitor, fenhexamid as a mixed/competitive inhibitor, chlordecone and rhothane as a mixed/uncompetitive inhibitor. In BeWo cells, all insecticides except endosulfan significantly decreased estradiol production at 100 µM. For rats, the IC50 values for dimethomorph, fenhexamid, and chlordecone were 11.98, 36.92, and 109.14 µM. Dimethomorph acts as a mixed inhibitor, while fenhexamid acts as a mixed/competitive inhibitor. Docking analysis revealed that endosulfan and fenhexamid bind to the steroid-binding site of human 17ß-HSD1. On the other hand, chlordecone and rhothane binds to a different site other than the steroid and NADPH-binding site. Dimethomorph binds to the steroid/NADPH binding site, and fenhexamid binds to the steroid binding site of rat 17ß-HSD1. Bivariate correlation analysis showed a positive correlation between IC50 values and LogP for human 17ß-HSD1, while a slight negative correlation was observed between IC50 values and the number of HBA. ADMET analysis provided insights into the toxicokinetics and toxicity of organochlorine pesticides. In conclusion, this study identified the inhibitory effects of 3-4 organochlorine pesticides and binding mechanisms on human and rat 17ß-HSD1, as well as their impact on hormone production.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38528218

RESUMO

Groundwater contamination have been widely concerned. To reliably conduct risk assessment, it is essential to accurately delineate the contaminant distribution and hydrogeological condition. Electrical resistivity tomography (ERT) has become a powerful tool because of its high sensitivity to hydrochemical parameters, as well as its advantages of non-invasiveness, spatial continuity, and cost-effectiveness. However, it is still difficult to integrate hydrochemical, hydrogeological, and ERT datasets for risk assessment. In this study, we develop a general framework for risk assessment by sequentially jointing hydrochemical, hydrogeological, and ERT surveys, while establishing petrophysical relationships among these data. This framework can be used in groundwater-contaminated site and help to delineate the distribution of contaminants. In this study, it was applied to a nitrogen-contaminated site where field ERT survey and borehole information provided valuable measurement data for validating the consistency of contamination and hydrogeological condition. Risk assessment was conducted based on the refined results by the establishment of relationship between conductivity and contaminants concentration with R 2 > 0.84 . The contamination source was identified and the transport direction was predicted with the good agreement of R 2 = 0.965 between simulated and observed groundwater head, which can help to propose measures for anti-seepage and monitoring. This study thus enhances the reliability of risk assessment and prediction through a thought-provoking innovation in the realm of groundwater environmental assessment.

5.
Carbohydr Polym ; 333: 121947, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494214

RESUMO

The rapid development of hydrogels has garnered significant attention in health monitoring and human motion sensing. However, the synthesis of multifunctional conductive hydrogels with excellent strain/pressure sensing and photoresponsiveness remains a challenge. Herein, the conductive hydrogels (BPTP) with excellent mechanical properties, fatigue resistance and photoresponsive behavior composed of polyacrylamide (PAM) matrix, 2,2,6,6-tetramethylpiperidin-1-yloxy-oxidized cellulose nanofibers (TOCNs) reinforcement and polydopamine-modified black phosphorus (BP@PDA) photosensitizer are prepared through a facile free-radical polymerization approach. The PDA adhered to the BP surface by π-π stacking promotes the optical properties of BP while also preventing BP oxidation from water. Through hydrogen bonding interactions, TOCNs improve the homogeneous dispersion of BP@PDA nanosheets and the mechanical toughness of BPTP. Benefiting from the synergistic effect of PDA and TOCNs, the conductive BPTP integrates superior mechanical performances, excellent photoelectric response and photothermal conversion capability. The BPTP-based sensor with high cycling stability demonstrates superior strain sensitivity (GF = 6.0) and pressure sensing capability (S = 0.13 kPa-1) to monitor various human activities. Therefore, this work delivers an alternative construction strategy for generating high-performance conductive hydrogels as multifunctional wearable sensors.


Assuntos
Celulose Oxidada , Dispositivos Eletrônicos Vestíveis , Humanos , Condutividade Elétrica , Hidrogéis , Ligação de Hidrogênio
6.
Micromachines (Basel) ; 15(3)2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38542568

RESUMO

With the development of high-voltage and high-frequency switching circuits, GaN high-electron-mobility transistor (HEMT) devices with high bandwidth, high electron mobility, and high breakdown voltage have become an important research topic in this field. It has been found that GaN HEMT devices have a drift in threshold voltage under the conditions of temperature and gate stress changes. Under high-temperature conditions, the difference in gate contact also causes the threshold voltage to shift. The variation in the threshold voltage affects the stability of the device as well as the overall circuit performance. Therefore, in this paper, a review of previous work is presented. Temperature variation, gate stress variation, and gate contact variation are investigated to analyze the physical mechanisms that generate the threshold voltage (VTH) drift phenomenon in GaN HEMT devices. Finally, improvement methods suitable for GaN HEMT devices under high-temperature and high-voltage conditions are summarized.

7.
Angew Chem Int Ed Engl ; : e202400515, 2024 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-38494466

RESUMO

Cyclobutanes with a gem-dimethyl group are common motifs in natural products. However, strategies for constructing enantioenriched gem-dimethyl cyclobutanes are still underdeveloped. Herein, we report an enantioselective approach to synthesize a broad group of chiral 2,3-disubstituted cyclobutanones through sequential 1,4-conjugate addition/trapping/cross-coupling of readily available cyclobutenones. The intermediate 2-bromocyclobutanone provides a valuable synthetic handle for further coupling transformations. In addition, this strategy was successfully utilized to synthesize gem-dimethyl cyclobutane-containing natural products, including (+)-ß-caryophyllene, (-)-raikovenal, (-)-1ß,9αH-5-linoleoyloxy-4,5-secocaryophyllen-4-one, and (-)-rumphellanones A-C.

8.
Cell Biol Int ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38436106

RESUMO

Mitochondrial dysfunction and myocardial remodeling have been reported to be the main underlying molecular mechanisms of doxorubicin-induced cardiotoxicity. SIRT6 is a nicotinamide adenine dinucleotide-dependent enzyme that plays a vital role in cardiac protection against various stresses. Moreover, previous studies have demonstrated that FSTL1 could alleviate doxorubicin-induced cardiotoxicity by inhibiting autophagy. The present study investigated the probable mechanisms of FSTL1 on doxorubicin-induced cardiotoxicity in vivo and in vitro. We confirmed that FSTL1 exerted a pivotal protective role on cardiac tissue in vivo and on doxorubicin-induced cell injury in vitro. Furthermore, FSTL1 can alleviate doxorubicin-induced mitochondrial dysfunction by inhibiting autophagy and apoptosis. Further studies demonstrated that FSTL1 can activate SIRT6 signaling by restoring the SIRT6 protein expression in doxorubicin-induced myocardial injury. SIRT6 activation elevated the protein expression of Nrf2 in doxorubicin-induced H9C2 injury. Treatment with the Nrf2 inhibitor ML385 partially antagonized the cardioprotective role of SIRT6 on doxorubicin-induced autophagy or apoptosis. These results suggested that the protective mechanism of FSTL1 on doxorubicin-induced cardiotoxicity may be related with the inhibition of autophagy and apoptosis, partly through the activation of SIRT6/Nrf2.

9.
Comp Biochem Physiol C Toxicol Pharmacol ; 281: 109900, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38518984

RESUMO

Benzophenone chemicals (BPs) have been developed to prevent the adverse effects of UV radiation and they are widely contaminated. 11ß-Hydroxysteroid dehydrogenase 1 (11ß-HSD1) catalyze the conversion of inactive glucocorticoid to active glucocorticoid, playing critical role in many physiological function. However, the direct effect of BPs on human, pig, rat, and mouse 11ß-HSD1 remains unclear. In this study, we screened the inhibitory strength of 12 BPs on 4 species, and performed the structure-activity relationship (SAR) and in silico docking analysis. The inhibitory potency of BPs was: for human 11ß-HSD1, BP6 (IC50 = 18.76 µM) > BP8 (40.84 µM) > BP (88.89 µM) > other BPs; for pig 11ß-HSD1, BP8 (45.57 µM) > BP6 (59.44 µM) > BP2 (65.12 µM) > BP (135.56 µM) > other BPs; for rat 11ß-HSD1, BP7 (67.17 µM) > BP (68.83 µM) > BP8 (133.04 µM) > other BPs; and for mouse 11ß-HSD1, BP8 (41.41 µM) > BP (50.61 µM) > other BPs. These BP chemicals were mixed/competitive inhibitors of these 11ß-HSD1 enzymes. The 2,2'-dihydroxy substitutions in two benzene rings play a key role in enhancing the effectiveness of inhibiting 11ß-HSD1, possibly via increasing hydrogen bond interactions. Docking analysis shows that these BPs bind to NADPH/glucocorticoid binding sites and forms hydrogen bonds with catalytic residues Ser and/or Tyr. In conclusion, this study demonstrates that BP chemicals can inhibit 11ß-HSD1 from 4 species, and there are subtle species-dependent difference in the inhibitory strength and structural variations of BPs.

10.
IEEE Trans Image Process ; 33: 2131-2144, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38478439

RESUMO

As a knowledge carrier, the diagram is widely distributed in many aspects of human life, such as textbooks, architectural drawings, and documents. Different from natural images, representations of visual elements in the diagram are sparser, and similar visual representations can reflect dissimilar semantics. Thus, current methods fail to capture the visual elements with precise semantics. To address this issue, regarding the aligned visual and textual elements as pairs is the way to assign the precise semantics of textual elements to visual elements. We build the first diagram dataset named align diagram element (ADE), which includes annotations for alignment relations between visual and textual elements. And we propose a visual-textual alignment model (VTAM) including graph construction and optimal aligning phases. In the graph construction phase, the relational graphs are constructed between different elements with four relational operators. The relational operators are designed to measure the relations between different elements, according to distance, connection line, inclusion, and feature similarity. In the optimal aligning phase, the representation at each visual-textual pair is improved as a weighted sum of the representations on all relational graphs. Experimental results show that our VTAM achieves a significant improvement of 10.9% on mean test folds of the ADE dataset than the current best competitor. In order to explore the role of alignment relations in diagram parsing, we introduce VTAM to diagram-related tasks, such as diagram question answering (DQA). And we achieve 2.8% to 5.9% and 4.6% to 5.1% improvements on AI2D and Foodwebs after adding VTAM. Our dataset and code are released at: https://github.com/ADE-dataset/ADE-dataset.

11.
Food Chem Toxicol ; 186: 114489, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38360388

RESUMO

Curcuminoids have many pharmacological effects. They or their metabolites may have side effects by suppressing 17ß-hydroxysteroid dehydrogenase 3 (17ß-HSD3). Herein, we investigated the inhibition of curcuminoids and their metabolites on human and rat 17ß-HSD3 and analyzed their structure-activity relationship (SAR) and performed in silico docking. Curcuminoids and their metabolites ranked in terms of IC50 values against human 17ß-HSD3 were bisdemethoxycurcumin (0.61 µM) > curcumin (8.63 µM) > demethoxycurcumin (9.59 µM) > tetrahydrocurcumin (22.04 µM) > cyclocurcumin (29.14 µM), and those against rat 17ß-HSD3 were bisdemethoxycurcumin (3.94 µM) > demethoxycurcumin (4.98 µM) > curcumin (9.62 µM) > tetrahydrocurcumin (45.82 µM) > cyclocurcumin (143.5 µM). The aforementioned chemicals were mixed inhibitors for both enzymes. Molecular docking analysis revealed that they bind to the domain between the androstenedione and NADPH active sites of 17ß-HSD3. Bivariate correlation analysis showed a positive correlation between LogP and pKa of curcumin derivatives with their IC50 values. Additionally, a 3D-QSAR analysis revealed that a pharmacophore model consisting of three hydrogen bond acceptor regions and one hydrogen bond donor region provided a better fit for bisdemethoxycurcumin compared to curcumin. In conclusion, curcuminoids and their metabolites possess the ability to inhibit androgen biosynthesis by directly targeting human and rat 17ß-HSD3. The inhibitory strength of these compounds is influenced by their lipophilicity and ionization characteristics.


Assuntos
17-Hidroxiesteroide Desidrogenases , Curcumina , Curcumina/análogos & derivados , Diarileptanoides , Piranos , Humanos , Ratos , Animais , Curcumina/farmacologia , Relação Quantitativa Estrutura-Atividade , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade
12.
Int. j. morphol ; 42(1): 46-51, feb. 2024. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1528827

RESUMO

SUMMARY: Few international studies have analyzed the characteristics of elite wheelchair curlers competing on the international stage. This study aims to investigate the physical fitness parameters of elite Chinese wheelchair curlers and explore the corresponding training enlightenment. Sixteen wheelchair curlers from the Chinese national team, including six male and two female Winter Paralympic gold medalists, were selected as research participants. The following parameters were measured: age, training age, height, weight, body fat percentage, grip strength, absolute bench press strength, and 5-km wheelchair push-timing test. Compared with ordinary curlers of the Chinese wheelchair curling team, elite curlers were older in age and training age; male curlers were shorter, whereas female curlers were taller. However, their weight and body fat percentage were lower, and their grip strength, absolute strength in the bench press, and 5-k wheelchair push-timing test were better. From an athlete development and physical training perspective, wheelchair curlers should increase training years in order to accumulate competition experience. Additionally, these athletes should manage their body weight and fat percentage, and improve their upper limb strength and aerobic capacity.


Pocos estudios internacionales han analizado las características de los curlers en silla de ruedas de élite que compiten en el escenario internacional. Este estudio tiene como objetivo investigar los parámetros de aptitud física de los bigudíes chinos en silla de ruedas de élite y explorar la iluminación del entrenamiento correspondiente. Se seleccionaron como participantes de la investigación dieciséis curlers en silla de ruedas del equipo nacional chino, incluidos seis medallistas de oro masculinos y dos femeninos de los Juegos Paralímpicos de Invierno. Se midieron los siguientes parámetros: edad, edad de entrenamiento, altura, peso, porcentaje de grasa corporal, fuerza de agarre, fuerza absoluta en press de banca y prueba de sincronización de empuje en silla de ruedas de 5 km. En comparación con los curlers ordinarios del equipo chino de curling en silla de ruedas, los curlers de élite eran mayores en edad y tiempo de entrenamiento; Los curlers masculinos eran más bajos, mientras que las mujeres eran más altas. Sin embargo, su peso y porcentaje de grasa corporal fueron menores, y su fuerza de agarre, fuerza absoluta en press de banca y prueba de sincronización de empuje en silla de ruedas de 5-k fueron mejores. Desde la perspectiva del desarrollo del atleta y del entrenamiento físico, los curlers en silla de ruedas deberían aumentar los años de entrenamiento para acumular experiencia en competencia. Además, estos deportistas deben controlar su peso corporal y porcentaje de grasa, y mejorar la fuerza de sus miembros superiores y su capacidad aeróbica.


Assuntos
Humanos , Masculino , Feminino , Adulto , Esportes , Cadeiras de Rodas , Aptidão Física , Antropometria
13.
Biomater Sci ; 12(5): 1274-1280, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38251092

RESUMO

Herein, we show a pair of leucine-rich L- and D-phosphopeptides which self-assemble into twisting nanofibers, whose secondary structures contain a strong ß-sheet component after being dephosphorylated by alkaline phosphatase (ALP). While being incubated with ALP overexpressing osteosarcoma cells, both of the peptides self-assemble in the nuclei and induce cell death. The cell death involves multiple cell death modalities and occurs along with the disruption of cell membranes. Enzyme-instructed self-assembly (EISA) inhibits osteosarcoma cells and shows no side effect to other cells. In addition, the cancer cells hardly gain drug resistance after repeated treatment. This work reports a pair of EISA-based nanofibers to target cell nuclei, and also provides a novel chemotherapeutic agent to inhibit osteosarcoma cells without side effects and drug resistance.


Assuntos
Neoplasias Ósseas , Osteossarcoma , Humanos , Leucina , Peptídeos/farmacologia , Peptídeos/química , Osteossarcoma/tratamento farmacológico , Morte Celular , Fosfatase Alcalina/metabolismo , Neoplasias Ósseas/tratamento farmacológico
14.
Environ Toxicol ; 39(5): 2560-2571, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38189224

RESUMO

Chlorinated bisphenol A (BPA) derivatives are formed during chlorination process of drinking water, whereas bisphenol S (BPS) and brominated BPA and BPS (TBBPA and TBBPS) were synthesized for many industrial uses such as fire retardants. However, the effect of halogenated BPA and BPS derivatives on glucocorticoid metabolizing enzyme 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1) remains unclear. The inhibitory effects of 6 BPA derivatives in the inhibition of human and rat 11ß-HSD1 were investigated. The potencies for inhibition on human 11ß-HSD1 were TBBPA (IC50, 3.87 µM) = monochloro BPA (MCBPA, 4.08 µM) = trichloro BPA (TrCBPA, 4.41 µM) > tetrachloro BPA (TCBPA, 9.75 µM) > TBBPS (>100 µM) = BPS (>100 µM), and those for rat 11ß-HSD1 were TrCBPA (IC50, 2.76 µM) = MCBPA (3.75 µM) > TBBPA (39.58 µM) > TCBPA = TBBPS = BPS. All these BPA derivatives are mixed/competitive inhibitors of both human and rat enzymes. Molecular docking studies predict that MCBPA, TrCBPA, TCBPA, and TBBPA all bind to the active site of human 11ß-HSD1, forming hydrogen bonds with catalytic residue Ser170 except TCBPA. Regression of the lowest binding energy with IC50 values revealed a significant inverse linear regression. In conclusion, halogenated BPA derivatives are mostly potent inhibitors of human and rat 11ß-HSD1, and there is structure-dependent inhibition.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1 , Compostos Benzidrílicos , Fenóis , Bifenil Polibromatos , Humanos , Ratos , Animais , Simulação de Acoplamento Molecular , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/química , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1/metabolismo , Relação Estrutura-Atividade
15.
Environ Toxicol ; 39(5): 2610-2622, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38205621

RESUMO

Perfluorotetradecanoic acid (PFTeDA) is a novel perfluoroalkyl substance that ubiquitously exists in the environment. However, whether PFTeDA affects adrenal cortex function remains unclear. Male Sprague-Dawley rats (age of 60 days) were daily administered with PFTeDA (0, 1, 5, and 10 mg/kg body weight) through gavage for 28 days. PFTeDA did not change body and adrenal gland weights. PFTeDA markedly elevated serum corticosterone level at 10 mg/kg but lowering serum aldosterone level at this dosage without influencing serum adrenocorticotropic hormone level. PFTeDA thickened zona fasciculata without affecting zona glomerulosa. PFTeDA remarkably upregulated the expression of corticosterone biosynthetic genes (Mc2r, Scarb1, Star, Cyp21, Cyp11b1, and Hsd11b1) and their proteins, whereas downregulating aldosterone biosynthetic enzyme Cyp11b2 and its protein, thereby distinctly altering their serum levels. PFTeDA markedly downregulated the expression of antioxidant genes (Sod1 and Sod2) and their proteins at 10 mg/kg. PFTeDA significantly decreased SIRT1/PGC1α and AMPK signaling while stimulating AKT1/mTOR signaling. Corticosterone significantly inhibited testosterone production by adult Leydig cells at >0.1 µM in vitro; however aldosterone significantly stimulated testosterone production at 0.1 nM. In conclusion, exposure to PFTeDA at male rat adulthood causes corticosterone excess and aldosterone deficiency via SIRT1/PGC1α, AMPK, and AKT1/mTOR signals, which in turn additively leads to testosterone deficiency.


Assuntos
Aldosterona , Corticosterona , Fluorocarbonos , Ratos , Masculino , Animais , Corticosterona/metabolismo , Aldosterona/metabolismo , Sirtuína 1/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Ratos Sprague-Dawley , Serina-Treonina Quinases TOR/metabolismo , Testosterona
16.
J Colloid Interface Sci ; 660: 923-933, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38280285

RESUMO

The flexible and self-healing supercapacitors (SCs) are considered to be promising smart energy storage devices. Nevertheless, the SCs integrated with flexibility, lightweight, pattern editability, self-healing capabilities and desirable electrochemical properties remain a challenge. Herein, an all-in-one self-healing SC fabricated with the free-standing hybrid film (TCMP) composed of the 2,2,6,6-tetramethylpiperidin-1-yloxy-oxidized cellulose nanofibers (TOCNs) carried carbon nanotubes (CNTs), manganese dioxide (MnO2) and polyaniline (PANI) as the electrode, polyvinyl alcohol/sulfuric acid (PVA/H2SO4) gel as the electrolyte and dynamically cross-linked cellulose nanofibers/PVA/sodium tetraborate decahydrate (CNF/PB) hydrogel as the self-healing electrode matrix is developed. The TCMP film electrodes are fabricated through a facile in-situ polymerization of MnO2 and PANI in TOCNs-dispersed CNTs composite networks, exhibiting lightweight, high electrical conductivity, flexibility, pattern editability and excellent electrochemical properties. Benefited from the hierarchically porous structure and high mechanical properties of TOCNs, excellent electrical conductivity of CNTs and the desirable synergistic effect of pseudocapacitance induced by MnO2 and PANI, the assembled SC with an interdigital structure demonstrated a high areal capacitance of 1108 mF cm-2 at 2 mA cm-2, large areal energy density of 153.7 µWh cm-2 at 1101.7 µW cm-2. A satisfactory bending cycle performance (capacitance retention up to 95 % after 200 bending deformations) and self-healing characteristics (∼90 % capacitance retention after 10 cut/repair cycles) are demonstrated for the TCMP-based symmetric SC, delivering a feasible strategy for electrochemical energy storage devices with excellent performance, designable patterns and desirable safe lifespan.

17.
ACS Nano ; 18(4): 3509-3519, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38241636

RESUMO

Intrauterine adhesions (IUA) refer to adhesions within the uterine cavity and cervix caused by injuries from uterine surgery. They are a significant cause of female infertility. Exosomes derived from mesenchymal stem cells (MSCs) play an active role in the treatment of IUA. However, the mechanism by which they reduce fibrosis in the damaged endometrium remains unclear. In this paper, we demonstrate that exosomes derived from placental mesenchymal stem cells (PMSCs) can restore uterine functions and improve the fertility rate of injured animals. This is achieved by promoting cell proliferation, increasing endometrial thickness, and reversing fibrosis. Regarding the molecular mechanism behind these therapeutic effects, we identify three specific miRNAs, namely, miR-125b-5p, miR-30c-5p, and miR-23a-3p, enriched in PMSC-exosomes, as the key players in the treatment of IUA. Specifically, miR-125b-5p/miR-30c-5p and miR-23a-3p inhibit the expression of smad2 and smad3 by targeting their 3'-untranslated regions, resulting in the downregulation of the transforming growth factor-ß (TGF-ß)/smad signaling pathway and the reversal of fibrosis. Notably, the safety of PMSC-exosomes in intrauterine treatment was also been confirmed. In conclusion, we illustrate that exosomes derived from PMSCs possess the capability to repair endometrial damage and enhance fertility in injured animals by regulating the TGF-ß/smad pathway via miR-125b-5p, miR-30c-5p, and miR-23a-3p. This provides insights into the precision treatment of IUA through exosome-based cell-free therapy.


Assuntos
Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Animais , Feminino , Gravidez , Fator de Crescimento Transformador beta/metabolismo , Exossomos/metabolismo , Placenta/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Células-Tronco Mesenquimais/metabolismo , Transdução de Sinais , Fibrose , Fatores de Crescimento Transformadores/metabolismo
18.
PLoS Pathog ; 20(1): e1011943, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38215174

RESUMO

Deubiquitinases (DUBs) remove ubiquitin from substrates and play crucial roles in diverse biological processes. However, our understanding of deubiquitination in viral replication remains limited. Employing an oncogenic human herpesvirus Kaposi's sarcoma-associated herpesvirus (KSHV) to probe the role of protein deubiquitination, we found that Ovarian tumor family deubiquitinase 4 (OTUD4) promotes KSHV reactivation. OTUD4 interacts with the replication and transcription activator (K-RTA), a key transcription factor that controls KSHV reactivation, and enhances K-RTA stability by promoting its deubiquitination. Notably, the DUB activity of OTUD4 is not required for K-RTA stabilization; instead, OTUD4 functions as an adaptor protein to recruit another DUB, USP7, to deubiquitinate K-RTA and facilitate KSHV lytic reactivation. Our study has revealed a novel mechanism whereby KSHV hijacks OTUD4-USP7 deubiquitinases to promote lytic reactivation, which could be potentially harnessed for the development of new antiviral therapies.


Assuntos
Herpesvirus Humano 8 , Proteínas Imediatamente Precoces , Sarcoma de Kaposi , Humanos , Proteínas Imediatamente Precoces/metabolismo , Peptidase 7 Específica de Ubiquitina/genética , Peptidase 7 Específica de Ubiquitina/metabolismo , Transativadores/genética , Herpesvirus Humano 8/genética , Replicação Viral , Regulação Viral da Expressão Gênica , Ativação Viral , Proteases Específicas de Ubiquitina/metabolismo
19.
Food Chem Toxicol ; 183: 114257, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38040240

RESUMO

The use of alternative substances to replace bisphenol A (BPA) has been encouraged. The objective of this study was to evaluate the effects of BPA and 9 BPA alternatives on human and rat aromatase (CYP19A1) in human and rat placental microsomes. The results revealed that bisphenol A, AP, B, C, E, F, FL, S, and Z, and 4,4'-thiodiphenol (TDP) inhibited human CYP19A1 and bisphenol A, AP, B, C, FL, Z, and TDP inhibited rat CYP19A1. The IC50 values of human CYP19A1 ranged from 3.3 to 172.63 µM and those of rat CYP19A1 ranged from 2.20 to over 100 µM. BPA alternatives were mixed/competitive inhibitors and inhibited estradiol production in BeWo placental cells. Molecular docking analysis showed that BPA alternatives bind to the domain between heme and steroid and form a hydrogen bond with catalytic residue Met374. Pharmacophore analysis showed that there were one hydrogen bond donor, one hydrophobic region, and one ring aromatic hydrophobic region. Bivariate correlation analysis showed that molecular weight, alkyl atom weight, and LogP of BPA alternatives were inversely correlated with their IC50 values. In conclusion, BPA alternatives can inhibit human and rat CYP19A1 and the lipophilicity and the substituted alkyl size determines their inhibitory strength.


Assuntos
Aromatase , Placenta , Humanos , Gravidez , Feminino , Animais , Ratos , Aromatase/metabolismo , Placenta/metabolismo , Simulação de Acoplamento Molecular , Linhagem Celular Tumoral , Relação Quantitativa Estrutura-Atividade , Citocromo P-450 CYP1A1/metabolismo , Compostos Benzidrílicos/farmacologia , Proteínas de Ligação a DNA
20.
J Steroid Biochem Mol Biol ; 236: 106424, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37939739

RESUMO

Bisphenol A (BPA) is a widely used plastic material and its potential endocrine disrupting effect has restricted its use and increasing use of BPA alternatives has raised health concerns. However, the effect of bisphenol alternatives on steroidogenesis remains unclear. The objective of this study was to compare inhibitory potencies of 10 BPA alternatives in the inhibition of gonadal 3ß-hydroxysteroid dehydrogenase (3ß-HSD) in three species (human, rat and mouse). The inhibitory potency for human 3ß-HSD2, rat 3ß-HSD1, and mouse 3ß-HSD6 ranged from bisphenol FL (IC50, 3.32 µM for human, 5.19 µM for rat, and 3.26 µM for mouse) to bisphenol E, F, and thiodiphenol (ineffective at 100 µM). Most BPA alternatives were mixed inhibitors of gonadal 3ß-HSD and they dose-dependently inhibited progesterone formation in KGN cells. Molecular docking analysis showed that all BPA analogs bind to steroid and NAD+ active sites. Lipophilicity of BPA alternatives was inversely correlated with IC50 values. In conclusion, BPA alternatives mostly can inhibit gonadal 3ß-HSDs and lipophilicity determines their inhibitory strength.


Assuntos
Compostos Benzidrílicos , Hidroxiesteroide Desidrogenases , Fenóis , Testículo , Ratos , Humanos , Camundongos , Animais , Masculino , Simulação de Acoplamento Molecular , Testículo/metabolismo , Relação Estrutura-Atividade , Hidroxiesteroide Desidrogenases/metabolismo , 3-Hidroxiesteroide Desidrogenases/metabolismo , 17-Hidroxiesteroide Desidrogenases/metabolismo
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