Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.071
Filtrar
1.
Cell Biol Int ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953242

RESUMO

Ferroptosis, a form of cell death driven by iron-dependent lipid peroxidation, is emerging as a promising target in cancer therapy. It is regulated by a network of molecules and pathways that modulate lipid metabolism, iron homeostasis and redox balance, and related processes. However, there are still numerous regulatory molecules intricately involved in ferroptosis that remain to be identified. Here, we indicated that suppression of Golgi protein acyl-coenzyme A binding domain A containing 3 (ACBD3) increased the sensitivity of Henrieta Lacks and PANC1 cells to ferroptosis. ACBD3 knockdown increases labile iron levels by promoting ferritinophagy. This increase in free iron, coupled with reduced levels of glutathione peroxidase 4 due to ACBD3 knockdown, leads to the accumulation of reactive oxygen species and lipid peroxides. Moreover, ACBD3 knockdown also results in elevated levels of polyunsaturated fatty acid-containing glycerophospholipids through mechanisms that remain to be elucidated. Furthermore, inhibition of ferrtinophagy in ACBD3 downregulated cells by knocking down the nuclear receptor co-activator 4 or Bafilomycin A1 treatment impeded ferroptosis. Collectively, our findings highlight the pivotal role of ACBD3 in governing cellular resistance to ferroptosis and suggest that pharmacological manipulation of ACBD3 levels is a promising strategy for cancer therapy.

2.
Beilstein J Org Chem ; 20: 1405-1411, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952958

RESUMO

Hypervalent iodine catalysis has been widely utilized in olefin functionalization reactions. Intermolecularly, the regioselective addition of two distinct nucleophiles across the olefin is a challenging process in hypervalent iodine catalysis. We introduce here a unique strategy using simple lithium salts for hypervalent iodine catalyst activation. The activated hypervalent iodine catalyst allows the intermolecular coupling of soft nucleophiles such as amides onto electronically activated olefins with high regioselectivity.

3.
J Adv Res ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38960279

RESUMO

INTRODUCTION: Glioblastoma multiforme (GBM) poses a significant challenge in terms of treatment due to its high malignancy, necessitating the identification of additional molecular targets. VSIG4, an oncogenic gene participates in tumor growth and migration in various cancer types. Nevertheless, the precise process through which VSIG4 facilitates the malignant progression of glioma remains to be elucidated. OBJECTIVES: This research aims to explore the function and molecular mechanism involving VSIG4 in the malignant progression of glioma. METHODS: The amount of VSIG4 was measured using qPCR, western blotting, and immunohistochemistry. Lentivirus infections were applied for upregulating or downregulating molecules within glioma cells. The incorporation of 5-ethynyl-20-deoxyuridine, Transwell, cell counting kit-8, and clone formation experiments, were applied to assess the biological functions of molecules on glioma cells. Dual luciferase reporter gene, RNA immunoprecipitation, and chromatin immunoprecipitation assays were used to explore the functional relationship among relevant molecules. RESULTS: The upregulation of VSIG4 was observed in GBM tissues, indicating an adverse prognosis. Silencing VSIG4 in glioma cells resulted in a decrease in cell viability, invasion, proliferation, and tumorigenesis, an increase in cell apoptosis, and a stagnation in the cell cycle progression at the G0/G1 phase. Mechanistically, SPI1-mediated upregulation of VSIG4 expression led to binding between VSIG4 and THBS1 protein, ultimately facilitating the malignant progression of glioma cells through the activation of the PI3K/AKT pathway. The inhibited proliferative and invasive capabilities of glioma cells were reversed by overexpressing THBS1 following the knockdown of VSIG4. CONCLUSION: Our findings provide evidence for the role of VSIG4 as an oncogene and reveal the previously unidentified contribution of the SPI1/VSIG4/THBS1 axis in the malignant progression of glioma. This signaling cascade enhances tumor growth and invasion by modulating the PI3K/AKT pathway. VSIG4 as a potential biomarker may be a viable strategy in the development of tailored molecular therapies for GBM.

4.
Chem Sci ; 15(27): 10491-10498, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38994426

RESUMO

The development of novel near-infrared (NIR) materials with extremely small energy gaps and high stability is highly desirable in bioimaging and phototherapy. Here we report an effective strategy for narrowing the energy gaps of porphyrins by synergistic regulation of meso/ß substituents. The novel NIR absorbing/emitting meso-alkynyl naphthoporphyrins (Zn-TNP and Pt-TNP) are synthesized via the retro-Diels-Alder reaction. X-ray crystallography analysis confirms the highly distorted structures of the complexes. Both compounds exhibit intense Q bands around 800 nm, while Zn-TNP shows deep NIR fluorescence at 847 nm. Pt-TNP displays NIR-II room temperature phosphorescence peaking at 1106 nm with an extremely large Stokes shift of 314 nm, which are the longest wavelengths observed among the reported platinum porphyrinoids. Furthermore, Pt-TNP shows remarkable photostability and a notable capacity for synchronous singlet oxygen and heat generation under NIR light irradiation, demonstrating potential in combined photodynamic/photothermal therapy. A theoretical analysis reveals the progressive lifting of the HOMO by the ß-fused benzene ring, the decrease of the LUMO upon meso-alkynyl substitution, and energy-releasing pathways varying with metal ions. This dual regulation approach demonstrates great promise in designing innovative multifunctional NIR porphyrin materials.

5.
J Colloid Interface Sci ; 675: 580-591, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38986331

RESUMO

Single-atom nanozymes (SANZs) have emerged as new media for enhancing chemodynamic therapy (CDT) to achieve desirable enzyme-like effects and excellent nanoscale specificity. However, non-optimal adsorption of Fenton-like reaction intermediates prevents SANZs from exerting kinetic activity and hinders the CDT effect. Herein, we demonstrate that heteroatom-doped Co single-atom nanozymes (SACNZs) with intrinsic charge transfer exhibit peroxidase-like properties and significantly improve the ability of CDT to treat Staphylococcus aureus-infected wounds. Density functional theory calculations showed that the S-induced charge transfer effect regulated the electronic distribution of the central metal more efficiently than P, thereby lowering the energy levels for the generation of OH and increasing the catalytic effect. Polyvinylpyrrolidone-modified SACNZs showed effects consistent with this theory in both in vitro antibacterial and in vivo ward management assays. This study systematically investigated the relationship between heteroatom-doping and the catalytic activity of metal centres, opening a new perspective for the application of CDT.

6.
BMJ Open ; 14(7): e082799, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39025815

RESUMO

BACKGROUND: Anaemia is a severe and common complication in patients with aneurysmal subarachnoid haemorrhage (aSAH). Early intervention for at-risk patients before anaemia occurs is indicated as potentially beneficial, but no validated method synthesises patients' complicated clinical features into an instrument. The purpose of the current study was to develop and externally validate a nomogram that predicted postacute phase anaemia after aSAH. METHODS: We developed a novel nomogram for aSAH patients to predict postacute phase anaemia (3 days after occurrence of aSAH, prior to discharge) on the basis of demographic information, imaging, type of treatment, aneurysm features, blood tests and clinical characteristics. We designed the model from a development cohort and tested the nomogram in external and prospective validation cohorts. We included 456 aSAH patients from The First Affiliated Hospital for the development, 220 from Sanmen People's Hospital for external validation and a prospective validation cohort that included 13 patients from Hangzhou Red Cross Hospital. We assessed the performance of the nomogram via concordance statistics and evaluated the calibration of predicted anaemia outcome with observed anaemia occurrence. RESULTS: Variables included in the nomogram were age, treatment method (open surgery or endovascular therapy), baseline haemoglobin level, fasting blood glucose level, systemic inflammatory response syndrome score on admission, Glasgow Coma Scale score, aneurysm size, prothrombin time and heart rate. In the validation cohort, the model for prediction of postacute phase anaemia had a c-statistic of 0.910, with satisfactory calibration (judged by eye) for the predicted and reported anaemia outcome. Among forward-looking forecasts, our predictive model achieved an 84% success rate, which showed that it has some clinical practicability. CONCLUSIONS: The developed and validated nomogram can be used to calculate individualised anaemia risk and has the potential to serve as a practical tool for clinicians in devising improved treatment strategies for aSAH.


Assuntos
Anemia , Nomogramas , Hemorragia Subaracnóidea , Humanos , Hemorragia Subaracnóidea/complicações , Feminino , Masculino , Pessoa de Meia-Idade , Anemia/etiologia , Anemia/diagnóstico , Anemia/sangue , Estudos Prospectivos , Idoso , Adulto , Aneurisma Intracraniano/complicações
7.
BMJ Open Respir Res ; 11(1)2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39032939

RESUMO

BACKGROUND: Impaired ventilatory efficiency during exercise is a predictor of mortality in chronic obstructive pulmonary disease. However, little is known about the clinical features and associated factors of impaired ventilatory efficiency in China. METHODS: We conducted a cross-sectional community-based study in China and collected demographic and clinical information, cardiopulmonary exercise testing, spirometry, and CT data. Impaired ventilatory efficiency was defined by a nadir ventilatory equivalent for CO2 production above the upper limit of normal. Multivariable linear and logistic regression models were used to explore the clinical features and associated factors of impaired ventilatory efficiency. RESULTS: The final analyses included 941 subjects, 702 (74.6%) of whom had normal ventilatory efficiency and 239 (25.4%) had impaired ventilatory efficiency. Participants with impaired ventilatory efficiency had more chronic respiratory symptoms, poorer lung function and exercise capacity, and more severe emphysema (natural logarithm transformation of the low-attenuation area of the lung with attenuation values below -950 Hounsfield units, logLAA-950: 0.19±0.65 vs -0.28±0.63, p<0.001) and air trapping (logLAA-856: 1.03±0.65 vs 0.68±0.70, p<0.001) than those with normal ventilatory efficiency. Older age (60-69 years, OR 3.10 (95% CI 1.33 to 7.21), p=0.009 and 70-80 years, OR 6.48 (95% CI 2.56 to 16.43), p<0.001 vs 40-49 years) and smoking (former, OR 3.19 (95% CI 1.29 to 7.86), p=0.012; current, OR 4.27 (95% CI 1.78 to 10.24), p=0.001 vs never) were identified as high risk factors of impaired ventilatory efficiency. CONCLUSIONS: Impaired ventilatory efficiency was associated with poorer respiratory characteristics. Longitudinal studies are warranted to explore the progression of individuals with impaired ventilatory efficiency.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Humanos , China/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Transversais , Idoso , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Espirometria , Teste de Esforço , Pulmão/fisiopatologia , Pulmão/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Tolerância ao Exercício , Fatores de Risco , Ventilação Pulmonar
8.
Zhongguo Zhong Yao Za Zhi ; 49(13): 3540-3547, 2024 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-39041125

RESUMO

The chemical constituents from the stems and leaves of Artocarpus tonkinensis in Artocarpus of Moraceae were systematically studied by means of silica gel, octadecylsilyl(ODS), and Sephadex LH-20 gel column chromatographies, as well as preparative high-performance liquid chromatography(Pre-HPLC) and a variety of chromatographic separation techniques. The spectral data and physicochemical properties of the compounds were obtained from separation and compared with those of the compounds reported in the literature. As a result, 11 compounds isolated from the 90% ethanol extract of the stems and leaves of A. tonkinensis were identified as artocatonkine(1), 5,6,7,4'-tetramethoxyflavone(2), apigenin-4'-O-ß-D-glucoside(3), rayalinol(4), psorachalcone A(5), 4-ketopinoresinol(6), ficusesquilignan B(7), pinnatifidanin AI(8), pinnatifidanin A(9), O-methylmellein(10), and trans-4-hydroxymellein(11). Among these compounds, compound 1 was a new prenylated flavone, and compounds 2-11 were isolated from the plants belonging to the genus Artocarpus for the first time. Furthermore, all compounds 1-11 were evaluated for their anti-rheumatoid arthritis activities, and the MTS method was used to measure their inhibitory effects on the proliferation of synovioblasts in vitro. The results of activity evaluation showed that flavonoid compounds 1-3, 5, and lignan compounds 8 and 9 displayed significant anti-rheumatoid arthritis activities, showing the IC_(50) values in inhibiting the proliferation of synovioblasts MH7A from(6.38±0.06) µmol·L~(-1) to(168.58±0.28)µmol·L~(-1).


Assuntos
Artocarpus , Proliferação de Células , Folhas de Planta , Caules de Planta , Artocarpus/química , Folhas de Planta/química , Caules de Planta/química , Proliferação de Células/efeitos dos fármacos , Humanos , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Linhagem Celular , Estrutura Molecular , Cromatografia Líquida de Alta Pressão
9.
Nanomaterials (Basel) ; 14(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38998712

RESUMO

Magnetic metal absorbing materials have exhibited excellent absorptance performance. However, their applications are still limited in terms of light weight, low thickness and wide absorption bandwidth. To address this challenge, we design a broadband and low-profile multilayer absorber using cobalt-iron (CoFe) alloys doped with rare earth elements (REEs) lanthanum (La) and Neodymium (Nd). An improved estimation of distribution algorithm (IEDA) is employed in conjunction with a mathematical model of multilayer absorbing materials (MAMs) to optimize both the relative bandwidth with reflection loss (RL) below -10 dB and the thickness. Firstly, the absorption performance of CoFe alloys doped with La/Nd with different contents is analysed. Subsequently, IEDA is introduced based on a mathematical model to achieve an optimal MAM design that obtains a balance between absorption bandwidth and thickness. To validate the feasibility of our proposed method, a triple-layer MAM is designed and optimized to exhibit wide absorption bandwidth covering C, X, and Ku bands (6.16-12.82 GHz) and a total thickness of 2.39 mm. Then, the electromagnetic (EM) absorption mechanisms of the triple-layer MAMs are systematically investigated. Finally, the triple-layer sample is further fabricated and measured. The experimental result is in good agreement with the simulated result. This paper presents a rapid and efficient optimization method for designing MAMs, offering promising prospects in microwave applications, such as radar-stealth technology, EM shielding, and reduced EM pollution for electronic devices.

10.
Nat Commun ; 15(1): 5747, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982069

RESUMO

Friction as a fundamental physical phenomenon dominates nature and human civilization, among which the achievement of molecular rolling lubrication is desired to bring another breakthrough, like the macroscale design of wheel. Herein, an edge self-curling nanodeformation phenomenon of graphite nanosheets (GNSs) at cryogenic temperature is found, which is then used to promote the formation of graphite nanorollers in friction process towards molecular rolling lubrication. The observation of parallel nanorollers at the friction interface give the experimental evidence for the occurrence of molecular rolling lubrication, and the graphite exhibits abnormal lubrication performance in vacuum with ultra-low friction and wear at macroscale. The molecular rolling lubrication mechanism is elucidated from the electronic interaction perspective. Experiments and theoretical simulations indicate that the driving force of the self-curling is the uneven atomic shrinkage induced stress, and then the shear force promotes the intact nanoroller formation, while the constraint of atomic vibration decreases the dissipation of driving stress and favors the nanoroller formation therein. It will open up a new pathway for controlling friction at microscale and nanostructural manipulation.

11.
Mater Horiz ; 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39026466

RESUMO

The overuse of antibiotics has led to the rapid development of multi-drug resistant bacteria, making antibiotics increasingly ineffective against bacterial infections. Consequently, there is an urgent need to develop alternative strategies to combat multi-drug-resistant bacterial infections. In this study, gold nanoparticles modified with ellagic acid (EA-AuNPs) were prepared using a simple and mild one-pot hydrothermal process. EA-AuNPs demonstrated high bactericidal efficacy and broad-spectrum antimicrobial activities against clinical isolates of the antibiotic-resistant ESKAPE pathogens. Furthermore, EA-AuNPs effectively disperse biofilms of multi-drug-resistant bacteria. Additionally, EA-AuNPs mitigated inflammatory responses at the bacterial infection sites. The combined bactericidal and anti-inflammatory treatment with EA-AuNPs resulted in faster curing of peritonitis caused by Staphylococcus aureus in mice compared to treatment with free EA or gentamicin. Moreover, transcriptome analysis revealed that EA-AuNPs exhibited a multi-targeting mechanism, making resistance development in pathogens more challenging than traditional antibiotics that recognize specific cellular targets. Overall, EA-AuNPs emerged as a promising antimicrobial agent against multi-drug-resistant bacterial infections.

12.
Sci Data ; 11(1): 804, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033167

RESUMO

The Tibetan Plateau (TP) is crucial for global climate change and China's ecological security. Given recent drastic changes in vegetation from climate change and human activities, long-term vegetation monitoring is urgently required. This study produced the vegetation maps of the TP from 1990 to 2020 every ten years using random forest classifier and Landsat imagery. We selected the same stable samples and features for mapping to reduce errors between years and proposed spatial filtering to further improve the accuracy. The overall accuracy surpassed 95.00%, with all Kappa coefficients exceeding 0.95. A further assessment based on sampling sites from literature and field survey was higher than 80%. The importance ranking results indicated that in the TP, climate factors and terrain factors are the most important factors in the vegetation mapping. This study provides a method for mapping vegetation in alpine areas and data support for researching the dynamic change of vegetation on the TP and evaluating its response to climate change.

13.
Microbiome ; 12(1): 130, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026313

RESUMO

BACKGROUND: The gut virome has been implicated in inflammatory bowel disease (IBD), yet a full understanding of the gut virome in IBD patients, especially across diverse geographic populations, is lacking. RESULTS: In this study, we conducted a comprehensive gut virome-wide association study in a Chinese cohort of 71 IBD patients (15 with Crohn's disease and 56 with ulcerative colitis) and 77 healthy controls via viral-like particle (VLP) and bulk virome sequencing of their feces. By utilizing an integrated gut virus catalog tailored to the IBD virome, we revealed fundamental alterations in the gut virome in IBD patients. These characterized 139 differentially abundant viral signatures, including elevated phages predicted to infect Escherichia, Klebsiella, Enterococcus_B, Streptococcus, and Veillonella species, as well as IBD-depleted phages targeting Prevotella, Ruminococcus_E, Bifidobacterium, and Blautia species. Remarkably, these viral signatures demonstrated high consistency across diverse populations such as those in Europe and the USA, emphasizing their significance and broad relevance in the disease context. Furthermore, fecal virome transplantation experiments verified that the colonization of these IBD-characterized viruses can modulate experimental colitis in mouse models. CONCLUSIONS: Building upon these insights into the IBD gut virome, we identified potential biomarkers for prognosis and therapy in IBD patients, laying the foundation for further exploration of viromes in related conditions. Video Abstract.


Assuntos
Fezes , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais , Viroma , Humanos , Microbioma Gastrointestinal/genética , Animais , Fezes/virologia , Fezes/microbiologia , Camundongos , Doenças Inflamatórias Intestinais/virologia , Doenças Inflamatórias Intestinais/microbiologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Doença de Crohn/virologia , Doença de Crohn/microbiologia , Bacteriófagos/genética , Bacteriófagos/isolamento & purificação , Colite Ulcerativa/virologia , Colite Ulcerativa/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , China , Transplante de Microbiota Fecal , Estudos de Casos e Controles , Vírus/classificação , Vírus/isolamento & purificação , Vírus/genética
14.
Scand J Immunol ; 99(4): e13352, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-39008028

RESUMO

Chimeric antigen receptor T-cell (CAR-T) therapy has demonstrated remarkable efficacy in treating relapsed/refractory acute B-cell lymphoblastic leukaemia (R/R B-ALL). However, a subset of patients does not benefit from CAR-T therapy. Our study aims to identify predictive indicators and establish a model to evaluate the feasibility of CAR-T therapy. Fifty-five R/R B-ALL patients and 22 healthy donors were enrolled. Peripheral blood lymphocyte subsets were analysed using flow cytometry. Sensitivity, specificity, accuracy, positive and negative predictive values and receiver operating characteristic (ROC) areas under the curve (AUC) were determined to evaluate the predictive values of the indicators. We identified B lymphocyte, regulatory T cell (Treg) and peripheral blood minimal residual leukaemia cells (B-MRD) as indicators for predicting the success of CAR-T cell preparation with AUC 0.936, 0.857 and 0.914. Furthermore, a model based on CD3+ T count, CD4+ T/CD8+ T ratio, Treg and extramedullary diseases (EMD) was used to predict the response to CAR-T therapy with AUC of 0.938. Notably, a model based on CD4+ T/CD8+ T ratio, B, Treg and EMD were used in predicting the success of CAR-T therapy with AUC 0.966 [0.908-1.000], with specificity (92.59%) and sensitivity (91.67%). In the validated group, the predictive model predicted the success of CAR-T therapy with specificity (90.91%) and sensitivity (100%). We have identified several predictive indicators for CAR-T cell therapy success and a model has demonstrated robust predictive capacity for the success of CAR-T therapy. These results show great potential for guiding informed clinical decisions in the field of CAR-T cell therapy.


Assuntos
Imunoterapia Adotiva , Receptores de Antígenos Quiméricos , Humanos , Imunoterapia Adotiva/métodos , Masculino , Feminino , Adulto , Adolescente , Pessoa de Meia-Idade , Receptores de Antígenos Quiméricos/imunologia , Criança , Leucemia-Linfoma Linfoblástico de Células Precursoras B/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Adulto Jovem , Pré-Escolar , Resultado do Tratamento , Linfócitos T Reguladores/imunologia , Curva ROC , Recidiva
15.
Langmuir ; 40(28): 14346-14354, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38953474

RESUMO

The issue of bacterial infectious diseases remains a significant concern worldwide, particularly due to the misuse of antibiotics, which has caused the emergence of antibiotic-resistant strains. Fortunately, the rapid development of nanomaterials has propelled significant progress in antimicrobial therapy, offering promising solutions. Among them, the utilization of nanoenzyme-based chemodynamic therapy (CDT) has become a highly hopeful approach to combating bacterial infectious diseases. Nevertheless, the application of CDT appears to be facing certain constraints for its low efficiency in the Fenton reaction at the infected site. In this study, we have successfully synthesized a versatile nanozyme, which was a composite of molybdenum sulfide (MoS2) and iron sulfide (FeS2), through the hydrothermal method. The results showed that iron/molybdenum sulfide nanozymes (Fe/Mo SNZs) with desirable peroxidase (POD) mimic activity can generate cytotoxic reactive oxygen species (ROS) by successfully triggering the Fenton reaction. The presence of MoS2 significantly accelerates the conversion of Fe2+/Fe3+ through a cocatalytic reaction that involves the participation of redox pairs of Mo4+/Mo6+, thereby enhancing the efficiency of CDT. Additionally, based on the excellent photothermal performance of Fe/Mo SNZs, a near-infrared (NIR) laser was used to induce localized temperature elevation for photothermal therapy (PTT) and enhance the POD-like nanoenzymatic activity. Notably, both in vitro and in vivo results demonstrated that Fe/Mo SNZs with good broad-spectrum antibacterial properties can help eradicate Gram-negative bacteria like Escherichia coli and Gram-positive bacteria like Staphylococcus aureus. The most exciting thing is that the synergistic PTT/CDT exhibited astonishing antibacterial ability and can achieve complete elimination of bacteria, which promoted wound healing after infection. Overall, this study presents a synergistic PTT/CDT strategy to address antibiotic resistance, providing avenues and directions for enhancing the efficacy of wound healing treatments and offering promising prospects for further clinical use in the near future.


Assuntos
Antibacterianos , Dissulfetos , Ferro , Molibdênio , Sulfetos , Cicatrização , Molibdênio/química , Molibdênio/farmacologia , Cicatrização/efeitos dos fármacos , Sulfetos/química , Sulfetos/farmacologia , Animais , Dissulfetos/química , Dissulfetos/farmacologia , Ferro/química , Ferro/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Catálise , Staphylococcus aureus/efeitos dos fármacos , Camundongos , Escherichia coli/efeitos dos fármacos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Nanoestruturas/química , Fototerapia , Testes de Sensibilidade Microbiana , Terapia Fototérmica , Compostos Ferrosos
16.
Small ; : e2403903, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953301

RESUMO

Asymmetric electronic environments based on microscopic-scale perspective have injected infinite vitality in understanding the intrinsic mechanism of polarization loss for electromagnetic (EM) wave absorption, but still exists a significant challenge. Herein, Zn single-atoms (SAs), structural defects, and Co nanoclusters are simultaneously implanted into bimetallic metal-organic framework derivatives via the two-step dual coordination-pyrolysis process. Theoretical simulations and experimental results reveal that the electronic coupling interactions between Zn SAs and structural defects delocalize the symmetric electronic environments and generate additional dipole polarization without sacrificing conduction loss owing to the compensation of carbon nanotubes. Moreover, Co nanoclusters with large nanocurvatures induce a strong interfacial electric field, activate the superiority of heterointerfaces and promote interfacial polarization. Benefiting from the aforementioned merits, the resultant derivatives deliver an optimal reflection loss of -58.9 dB and the effective absorption bandwidth is 5.2 GHz. These findings provide an innovative insight into clarifying the microscopic loss mechanism from the asymmetric electron environments viewpoint and inspire the generalized electronic modulation engineering in optimizing EM wave absorption.

17.
Phys Chem Chem Phys ; 26(28): 19543-19553, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38979972

RESUMO

Rational design of γ-alumina-based catalysts relies on an extensive understanding of the distribution of hydroxyl groups on the surface of γ-alumina and their physicochemical properties, which remain unclear and challenging to determine experimentally due to the structural complexity. In this work, by means of DFT and thermodynamic calculations, various hydroxylation modes of γ-alumina (110) and (100) surfaces at different OH coverages were evaluated, based on which a thermodynamic model to reflect the relationship between temperature and the surface structure was established and the stable hydroxylation modes under experimental conditions were predicted. This enables us to identify the experimentally measured IR spectra. The effect of hydroxyl coverages on the surface Lewis acidity was then analyzed, showing that the presence of hydroxyl groups could promote the Lewis acidity of neighboring Al sites. This work provides fundamental insights into the molecular level understanding of the surface properties of γ-alumina and benefits the rational design of alumina-based catalysts.

18.
Int Immunopharmacol ; 139: 112719, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39032470

RESUMO

Autophagy in alveolar macrophages (AMs) is an important mechanism for maintaining immune homeostasis and normal lung tissue function, and insufficient autophagy in AMs may mediate the development of sepsis-induced acute lung injury (SALI). Insufficient autophagy in AMs and the activation of the NLRP3 inflammasome were observed in a mouse model with SALI induced by cecal ligation and puncture (CLP), resulting in the release of a substantial quantity of proinflammatory factors and the formation of SALI. However, after andrographolide (AG) intervention, autophagy in AMs was significantly promoted, the activation of the NLRP3 inflammasome was inhibited, the release of proinflammatory factors and pyroptosis were suppressed, and SALI was then ameliorated. In the MH-S cell model stimulated with LPS, insufficient autophagy was discovered to promote the overactivation of the NLRP3 inflammasome. AG was found to significantly promote autophagy, inhibit the activation of the NLRP3 inflammasome, and attenuate the release of proinflammatory factors. The primary mechanism of AG promoting autophagy was to inhibit the activation of the PI3K/AKT/mTOR pathway by binding RAGE to the membrane. In addition, it inhibited the activation of the NLRP3 inflammasome to ameliorate SALI. Our findings suggest that AG promotes autophagy in AMs through the RAGE/PI3K/AKT/mTOR pathway to inhibit the activation of the NLRP3 inflammasome, remodel the functional homeostasis of AMs in SALI, and exert anti-inflammatory and lung-protective effects. It has also been the first to suggest that RAGE is likely a direct target through which AG regulates autophagy, providing theoretical support for a novel therapeutic strategy in sepsis.

19.
Nat Commun ; 15(1): 5127, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879565

RESUMO

The Omicron subvariants BQ.1.1, XBB.1.5, and XBB.1.16 of SARS-CoV-2 are known for their adeptness at evading immune responses. Here, we isolate a neutralizing antibody, 7F3, with the capacity to neutralize all tested SARS-CoV-2 variants, including BQ.1.1, XBB.1.5, and XBB.1.16. 7F3 targets the receptor-binding motif (RBM) region and exhibits broad binding to a panel of 37 RBD mutant proteins. We develop the IgG-like bispecific antibody G7-Fc using 7F3 and the cross-neutralizing antibody GW01. G7-Fc demonstrates robust neutralizing activity against all 28 tested SARS-CoV-2 variants and sarbecoviruses, providing potent prophylaxis and therapeutic efficacy against XBB.1 infection in both K18-ACE and BALB/c female mice. Cryo-EM structure analysis of the G7-Fc in complex with the Omicron XBB spike (S) trimer reveals a trimer-dimer conformation, with G7-Fc synergistically targeting two distinct RBD epitopes and blocking ACE2 binding. Comparative analysis of 7F3 and LY-CoV1404 epitopes highlights a distinct and highly conserved epitope in the RBM region bound by 7F3, facilitating neutralization of the immune-evasive Omicron variant XBB.1.16. G7-Fc holds promise as a potential prophylactic countermeasure against SARS-CoV-2, particularly against circulating and emerging variants.


Assuntos
Anticorpos Biespecíficos , Anticorpos Antivirais , COVID-19 , Camundongos Endogâmicos BALB C , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Animais , SARS-CoV-2/imunologia , SARS-CoV-2/genética , Anticorpos Biespecíficos/imunologia , Anticorpos Biespecíficos/farmacologia , COVID-19/imunologia , COVID-19/virologia , COVID-19/prevenção & controle , Humanos , Feminino , Camundongos , Anticorpos Antivirais/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Anticorpos Neutralizantes/imunologia , Testes de Neutralização , Microscopia Crioeletrônica , Células HEK293
20.
Mol Nutr Food Res ; 68(12): e2300833, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38850176

RESUMO

SCOPE: Alcoholic liver disease (ALD) is a global public health concern. Nobiletin, a polymethoxyflavone abundant in citrus fruits, enhances circadian rhythms and ameliorates diet-induced hepatic steatosis, but its influences on ALD are unknown. This study investigates the role of brain and muscle Arnt-like protein-1 (Bmal1), a key regulator of the circadian clock, in nobiletin-alleviated ALD. METHODS AND RESULTS: This study uses chronic ethanol feeding plus an ethanol binge to establish ALD models in Bmal1flox/flox and Bmal1 liver-specific knockout (Bmal1LKO) mice. Nobiletin mitigates ethanol-induced liver injury (alanine aminotransferase [ALT]), glucose intolerance, hepatic apoptosis, and lipid deposition (triglyceride [TG], total cholesterol [TC]) in Bmal1flox/flox mice. Nobiletin fails to modulated liver injury (ALT, aspartate aminotransferase [AST]), apoptosis, and TG accumulation in Bmal1LKO mice. The expression of lipogenic genes (acetyl-CoA carboxylase alpha [Acaca], fatty acid synthase [Fasn]) and fatty acid oxidative genes (carnitine pamitoyltransferase [Cpt1a], cytochrome P450, family 4, subfamily a, polypeptide 10 [Cyp4a10], and cytochrome P450, family4, subfamily a, polypeptide 14 [Cyp4a14]) is inhibited, and the expression of proapoptotic genes (Bcl2 inteacting mediator of cell death [Bim]) is enhanced by ethanol in Bmal1flox/flox mice. Nobiletin antagonizes the expression of these genes in Bmal1flox/flox mice and not in Bmal1LKO mice. Nobiletin activates protein kinase B (PKB, also known as AKT) phosphorylation, increases the levels of the carbohydrate response element binding protein (ChREBP), ACC1, and FASN, and reduces the level of sterol-regulatory element binding protein 1 (SREBP1) and phosphorylation of ACC1 in a Bmal1-dependent manner. CONCLUSION: Nobiletin alleviates ALD by increasing the expression of genes involved in fatty acid oxidation by increasing AKT phosphorylation and lipogenesis in a Bmal1-dependent manner.


Assuntos
Fatores de Transcrição ARNTL , Flavonas , Lipogênese , Hepatopatias Alcoólicas , Camundongos Knockout , Proteínas Proto-Oncogênicas c-akt , Animais , Flavonas/farmacologia , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Hepatopatias Alcoólicas/prevenção & controle , Hepatopatias Alcoólicas/metabolismo , Hepatopatias Alcoólicas/tratamento farmacológico , Lipogênese/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Masculino , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Camundongos , Substâncias Protetoras/farmacologia , Etanol , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA