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1.
Nature ; 622(7984): 754-760, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37730999

RESUMEN

Single-atom catalysts (SACs) have well-defined active sites, making them of potential interest for organic synthesis1-4. However, the architecture of these mononuclear metal species stabilized on solid supports may not be optimal for catalysing complex molecular transformations owing to restricted spatial environment and electronic quantum states5,6. Here we report a class of heterogeneous geminal-atom catalysts (GACs), which pair single-atom sites in specific coordination and spatial proximity. Regularly separated nitrogen anchoring groups with delocalized π-bonding nature in a polymeric carbon nitride (PCN) host7 permit the coordination of Cu geminal sites with a ground-state separation of about 4 Å at high metal density8. The adaptable coordination of individual Cu sites in GACs enables a cooperative bridge-coupling pathway through dynamic Cu-Cu bonding for diverse C-X (X = C, N, O, S) cross-couplings with a low activation barrier. In situ characterization and quantum-theoretical studies show that such a dynamic process for cross-coupling is triggered by the adsorption of two different reactants at geminal metal sites, rendering homo-coupling unfeasible. These intrinsic advantages of GACs enable the assembly of heterocycles with several coordination sites, sterically congested scaffolds and pharmaceuticals with highly specific and stable activity. Scale-up experiments and translation to continuous flow suggest broad applicability for the manufacturing of fine chemicals.

2.
Mol Ther ; 32(5): 1387-1406, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38414247

RESUMEN

Cisplatin-induced hearing loss is a common side effect of cancer chemotherapy in clinics; however, the mechanism of cisplatin-induced ototoxicity is still not completely clarified. Cisplatin-induced ototoxicity is mainly associated with the production of reactive oxygen species, activation of apoptosis, and accumulation of intracellular lipid peroxidation, which also is involved in ferroptosis induction. In this study, the expression of TfR1, a ferroptosis biomarker, was upregulated in the outer hair cells of cisplatin-treated mice. Moreover, several key ferroptosis regulator genes were altered in cisplatin-damaged cochlear explants based on RNA sequencing, implying the induction of ferroptosis. Ferroptosis-related Gpx4 and Fsp1 knockout mice were established to investigate the specific mechanisms associated with ferroptosis in cochleae. Severe outer hair cell loss and progressive damage of synapses in inner hair cells were observed in Atoh1-Gpx4-/- mice. However, Fsp1-/- mice showed no significant hearing phenotype, demonstrating that Gpx4, but not Fsp1, may play an important role in the functional maintenance of HCs. Moreover, findings showed that FDA-approved luteolin could specifically inhibit ferroptosis and alleviate cisplatin-induced ototoxicity through decreased expression of transferrin and intracellular concentration of ferrous ions. This study indicated that ferroptosis inhibition through the reduction of intracellular ferrous ions might be a potential strategy to prevent cisplatin-induced hearing loss.


Asunto(s)
Cisplatino , Ferroptosis , Pérdida Auditiva , Ratones Endogámicos C57BL , Ratones Noqueados , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Animales , Cisplatino/efectos adversos , Ferroptosis/efectos de los fármacos , Ferroptosis/genética , Ratones , Pérdida Auditiva/inducido químicamente , Pérdida Auditiva/genética , Pérdida Auditiva/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/genética , Modelos Animales de Enfermedad , Receptores de Transferrina/metabolismo , Receptores de Transferrina/genética , Especies Reactivas de Oxígeno/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Células Ciliadas Auditivas Externas/metabolismo , Células Ciliadas Auditivas Externas/efectos de los fármacos , Células Ciliadas Auditivas Externas/patología , Ototoxicidad/etiología , Ototoxicidad/metabolismo , Antineoplásicos/efectos adversos , Apoptosis/efectos de los fármacos
3.
Nano Lett ; 24(4): 1447-1453, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38252892

RESUMEN

Passive solar heating and radiative cooling have attracted great interest in global energy consumption reduction due to their unique electricity-free advantage. However, static single radiation cooling or solar heating would lead to overcooling or overheating in cold and hot weather, respectively. To achieve a facile, effective approach for dynamic thermal management, a novel structured polyethylene (PE) film was engineered with a switchable cooling and heating mode obtained through a moisture transfer technique. The 100 µm PE film showed excellent solar modulation from 0.92 (dried state) to 0.32 (wetted state) and thermal modulation from 0.86 (dried state) to 0.05 (wetted state). Outdoor experiments demonstrated effective thermal regulation during both daytime and nighttime. Furthermore, our designed PE film can save 1.3-41.0% of annual energy consumption across the whole country of China. This dual solar and thermal regulation mechanism is very promising for guiding scalable approaches to energy-saving temperature regulation.

4.
Cell Immunol ; 401-402: 104845, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38909549

RESUMEN

CD147 is a T cell activation-associated molecule which is closely involved in the formation of the immune synapse (IS). However, the precise role of CD147 in T cell activation and IS formation remains unclear. In the present study, we demonstrated that CD147 translocated to the IS upon T cell activation and was primarily distributed in the peripheral super molecular cluster (p-SMAC). The knock down of CD147 expression in T cells, but not in B cells, impaired IS formation. CD147 participated in IS formation between T cells and different types of antigen-presenting cells (APCs), including macrophages and dendritic cells. Ligation of CD147 with its monoclonal antibody (mAb) HAb18 effectively inhibited T cell activation and IL-2 secretion. CD98, a critical molecule interacting with CD147, was distributed in IS in a CD147-dependent way. Phosphorylation levels of T cell receptor (TCR) related molecules, like ZAP-70, ERK, and cJun, were down-regulated by CD147 ligation, which is crucial for the interaction of CD147 and TCR signaling transduction. CD147 is indispensable for the formation of immune synapses and plays an important role in the regulation of its function.

5.
Reprod Biomed Online ; 48(3): 103571, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38244346

RESUMEN

RESEARCH QUESTION: Are blastocysts derived from in-vitro-matured metaphase I (MI) oocytes less likely to produce usable embryos for transfer compared with those derived from in-vivo-matured oocytes in cycles undergoing preimplantation genetic testing (PGT)? DESIGN: The primary outcome was usable blastocyst rate, which was compared between blastocysts derived from in-vitro-matured MI oocytes after ovarian stimulation and from in-vivo-matured oocytes. Logistic regression analysis using generalized estimating equations was used to control for confounders in the analysis of factors that may influence the chance of a blastocyst being usable and in the comparison of embryological outcomes. Student's t-test, Mann-Whitney U test, chi-squared tests or Fisher's exact tests were used to compare clinical and pregnancy outcomes. RESULTS: A total of 1810 injected metaphase II (MII) oocytes from 154 PGT cycles involving 154 couples were included in this study. A total of 1577 MII oocytes were in-vivo-matured and 233 were in-vitro-matured MI oocytes. The usable blastocyst rate was similar between the in-vitro-matured MI oocyte group and the in-vivo-matured oocyte group (adjusted RR 0.97, 95% CI 0.40 to 2.34). Three live births were achieved using usable blastocysts derived from in-vitro-matured MI oocytes. CONCLUSIONS: If in-vitro-matured MI oocytes can be fertilized and develop into blastocysts, their ability to provide usable embryos for transfer is similar compared with those developed from in-vivo-matured oocytes. These blastocysts could be considered valuable for women with few viable embryos in assisted reproductive technology cycles.


Asunto(s)
Oocitos , Resultado del Embarazo , Embarazo , Humanos , Femenino , Metafase , Oocitos/fisiología , Pruebas Genéticas , Blastocisto/fisiología
6.
BMC Cardiovasc Disord ; 24(1): 82, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38297207

RESUMEN

BACKGROUND: Pathological cardiac hypertrophy is associated with cardiac dysfunction and is a key risk factor for heart failure and even sudden death. This study investigates the function of Mycn in cardiac hypertrophy and explores the interacting molecules. METHODS: A mouse model of cardiac hypertrophy was induced by isoproterenol (ISO). The cardiac dysfunction was assessed by the heart weight-to-body weight ratio (HW/BW), echocardiography assessment, pathological staining, biomarker detection, and cell apoptosis. Transcriptome alteration in cardiac hypertrophy was analyzed by bioinformatics analysis. Gain- or loss-of-function studies of MYCN proto-oncogene (Mycn), ubiquitin specific peptidase 2 (USP2), and junction plakoglobin (JUP) were performed. The biological functions of Mycn were further examined in ISO-treated cardiomyocytes. The molecular interactions were verified by luciferase assay or immunoprecipitation assays. RESULTS: Mycn was poorly expressed in ISO-treated mice, and its upregulation reduced HW/BW, cell surface area, oxidative stress, and inflammation while improving cardiac function of mice. It also reduced apoptosis of cardiomyocytes in mice and those in vitro induced by ISO. Mycn bound to the USP2 promoter to activate its transcription. USP2 overexpression exerted similar myocardial protective functions. It stabilized JUP protein by deubiquitination modification, which blocked the Akt/ß-catenin pathway. Knockdown of JUP restored phosphorylation of Akt and ß-catenin protein level, which negated the protective effects of USP2. CONCLUSION: This study demonstrates that Mycn activates USP2 transcription, which mediates ubiquitination and protein stabilization of JUP, thus inactivating the Akt/ß-catenin axis and alleviating cardiac hypertrophy-induced heart failure.


Asunto(s)
Insuficiencia Cardíaca , Proteína Proto-Oncogénica N-Myc , Animales , Ratones , beta Catenina/genética , beta Catenina/metabolismo , Cardiomegalia/genética , Cardiomegalia/prevención & control , gamma Catenina/metabolismo , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/prevención & control , Isoproterenol , Miocitos Cardíacos/metabolismo , Proteína Proto-Oncogénica N-Myc/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal
7.
BMC Psychiatry ; 24(1): 315, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38658886

RESUMEN

BACKGROUND: Breast cancer is the most common malignant tumor in females worldwide. During disease development, breast cancer patients suffer anxious and depressed, which may lead to worse quality of life or even higher mortality. Esketamine has been regarded as an antidepressant in breast cancer patients with mild or moderate depression. Here, we wonder whether the administration of esketamine could reduce the postoperative depressive symptom score of breast cancer patients who have no preoperative depression. METHODS: A total of 64 patients treated with unilateral modified radical mastectomy were randomly divided into an experimental group (esketamine group, Group E) and a control group (Group C), with 32 cases in each one. After anesthesia induction, Group C received 0.2 ml/kg of normal saline intravenously and Group E was administered 0.2 mg/kg intravenous esketamine. The primary outcome was the Patient Health Questionnaire-9 (PHQ-9) scores. The secondary outcomes included the Visual Analogue Scale (VAS) scores for pain, inflammatory markers, perioperative-related indicators, and the incidence of postoperative delirium, nausea and vomiting. RESULTS: The PHQ-9 score on postoperative day (POD) 1 in Group E declined from the preoperative level, while the score in Group C was higher than before, and the former was far lower than the latter (P = 0.047). There is no statistically significant difference in PHQ-9 scores between Group E and Group C on POD 3, 7, and 30. Moreover, the postoperative leukocyte level of Group E was higher than that of Group C, and the difference was statistically significant (P = 0.030). CONCLUSIONS: A single subanesthetic dose of esketamine can result in lower postoperative score on subthreshold depressive symptoms compared to the Group C on POD 1, without increasing the occurrence of postoperative adverse reactions. TRIAL REGISTRATION: Registration number: Chinese Clinical Trial Registry ChiCTR2200057028. Date of registration: 26/02/2022.


Asunto(s)
Neoplasias de la Mama , Depresión , Ketamina , Mastectomía Radical Modificada , Humanos , Ketamina/administración & dosificación , Ketamina/uso terapéutico , Femenino , Persona de Mediana Edad , Método Doble Ciego , Neoplasias de la Mama/cirugía , Adulto , Complicaciones Posoperatorias/prevención & control , Antidepresivos/uso terapéutico , Antidepresivos/administración & dosificación
8.
BMC Geriatr ; 24(1): 271, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38504166

RESUMEN

INTRODUCTION: Frailty has become a worldwide health burden that has a large influence on public health and clinical practice. The incidence of frailty is anticipated to increase as the ageing population increases. Myocardial injury after noncardiac surgery (MINS) is associated with short-term and long-term mortality. However, the incidence of MINS in frail geriatric patients is unknown. METHODS AND ANALYSIS: This prospective, multicentre, real-world observational cohort study will be conducted at 18 designated centres in China from January 2023 to December 2024, with an anticipated sample size of 856 patients aged 65 years and older who are scheduled to undergo noncardiac surgery. The primary outcome will be the incidence of MINS. MINS is defined as a fourth-generation plasma cardiac troponin T (cTnT) concentration ≥ 0.03 ng/mL exhibited at least once within 30 days after surgery, with or without symptoms of myocardial ischaemia. All data will be collected via electronic data acquisition. DISCUSSION: This study will explore the incidence of MINS in frail patients. The characteristics, predictive factors and 30-day outcomes of MINS in frail patients will be further investigated to lay the foundation for identifying clinical interventions. CLINICAL TRIAL REGISTRATION: https://beta. CLINICALTRIALS: gov/study/NCT05635877 , NCT05635877.


Asunto(s)
Fragilidad , Isquemia Miocárdica , Humanos , Anciano , Complicaciones Posoperatorias/diagnóstico , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Estudios Prospectivos , Fragilidad/diagnóstico , Fragilidad/epidemiología , Fragilidad/complicaciones , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/epidemiología , Isquemia Miocárdica/etiología , Estudios de Cohortes , Factores de Riesgo , Estudios Observacionales como Asunto , Estudios Multicéntricos como Asunto
9.
BMC Musculoskelet Disord ; 25(1): 287, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38614972

RESUMEN

BACKGROUND: An accessory extreme far anteromedial portal can improve visualisation and ease inferior leaf meniscectomy in patients with lateral meniscal anterior horn horizontal tears. However, the therapeutic outcomes of adding an accessory extreme far anteromedial portal remain unclear. This study aimed to evaluate the clinical efficacy of adding an accessory extreme far anteromedial portal for treating lateral meniscal horizontal tears involving the anterior horns. METHODS: This retrospective study included 101 patients with anterior horn involvement in lateral meniscal horizontal tears who underwent arthroscopic unstable inferior leaf meniscectomy between January 2016 and December 2020. The pathologies were diagnosed using physical examinations and magnetic resonance imaging. The anterior horn involved in the lateral meniscal horizontal tears was treated using inferior leaf meniscectomy. The primary endpoints were changes in the visual analogue scale, Lysholm, International Knee Documentation Committee, and Tegner scores at the final follow-up. The secondary endpoint was meniscal cure rate at 3 months postoperatively. The preoperative and postoperative functional scores were compared. The occurrence of complications was recorded. RESULTS: All patients were followed up for an average of 4.9 ± 1.2 years (range 2.3-7.5 years). After 4 months, none of the patients experienced pain, weakness, instability, or tenderness in the lateral joint line, achieving an imaging cure rate of 98%. At the final follow-up, significant postoperative improvements were observed in the average values of the visual analogue scale score (3.5 ± 0.7 vs. 0.7 ± 0.6), Lysholm score (62.7 ± 4.4 vs. 91.8 ± 3.1), International Knee Documentation Committee score (61.9 ± 3.7 vs. 91.7 ± 9.5), and Tegner score (2.0 ± 0.7 vs. 6.1 ± 0.7). Excellent Lysholm scores were obtained in 81 patients, and good outcomes were obtained in 18 patients, with an excellent-to-good rate of 98.0%. CONCLUSIONS: Inferior leaf resection via the accessory far anteromedial portal is a safe treatment option for the involved anterior horn in lateral meniscal horizontal tears. This approach enhances visibility and facilitates surgical procedures, with minimal complications.


Asunto(s)
Meniscectomía , Meniscos Tibiales , Animales , Humanos , Meniscos Tibiales/diagnóstico por imagen , Meniscos Tibiales/cirugía , Estudios Retrospectivos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Artroscopía
10.
Int J Mol Sci ; 25(5)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38473708

RESUMEN

DNA lesions trigger DNA damage checkpoint (DDC) signaling which arrests cell cycle progression and promotes DNA damage repair. In Saccharomyces cerevisiae, phosphorylation of histone H2A (γH2A, equivalent to γH2AX in mammals) is an early chromatin mark induced by DNA damage that is recognized by a group of DDC and DNA repair factors. We find that γH2A negatively regulates the G2/M checkpoint in response to the genotoxin camptothecin, which is a DNA topoisomerase I poison. γH2A also suppresses DDC signaling induced by the DNA alkylating agent methyl methanesulfonate. These results differ from prior findings, which demonstrate positive or no roles of γH2A in DDC in response to other DNA damaging agents such as phleomycin and ionizing radiation, which suggest that γH2A has DNA damage-specific effects on DDC signaling. We also find evidence supporting the notion that γH2A regulates DDC signaling by mediating the competitive recruitment of the DDC mediator Rad9 and the DNA repair factor Rtt107 to DNA lesions. We propose that γH2A/γH2AX serves to create a dynamic balance between DDC and DNA repair that is influenced by the nature of DNA damage.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Daño del ADN , Histonas/metabolismo , ADN/metabolismo
11.
Apoptosis ; 28(3-4): 432-446, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36484960

RESUMEN

Obstructive sleep apnea (OSA), characterized by chronic intermittent hypoxia (CIH), is a common risk factor for pulmonary arterial hypertension (PAH). As a hypoxia-induced transcription factor, differentially expressed in chondrocytes (DEC1) negatively regulates the transcription of peroxisome proliferative activated receptor-γ (PPARγ), a recognized protective factor of PAH. However, whether and how DEC1 is associated with PAH pathogenesis remains unclear. In the present study, we found that DEC1 was increased in lungs and pulmonary arterial smooth muscle cells (PASMCs) of rat models of OSA-associated PAH. Oxidative indicators and inflammatory cytokines were also elevated in the blood of the rats. Similarly, hypoxia-treated PASMCs displayed enhanced DEC1 expression and reduced PPARγ expression in vitro. Functionally, DEC1 overexpression exacerbated reactive oxygen species (ROS) production and the expression of pro-inflammatory cytokines (such as TNFα, IL-1ß, IL-6, and MCP-1) in PASMCs. Conversely, shRNA knockdown of Dec1 increased PPARγ expression but attenuated hypoxia-induced oxidative stress and inflammatory responses in PASMCs. Additionally, DEC1 overexpression promoted PASMC proliferation, which was drastically attenuated by a PPARγ agonist rosiglitazone. Collectively, these results suggest that hypoxia-induced DEC1 inhibits PPARγ, and that this is a predominant mechanism underpinning oxidative stress and inflammatory responses in PASMCs during PAH. DEC1 could be used as a potential target to treat PAH.


Asunto(s)
Hipertensión Arterial Pulmonar , Apnea Obstructiva del Sueño , Ratas , Animales , Hipertensión Arterial Pulmonar/inducido químicamente , Hipertensión Arterial Pulmonar/genética , Hipertensión Arterial Pulmonar/patología , PPAR gamma/genética , PPAR gamma/metabolismo , Ratas Sprague-Dawley , Apoptosis , Arteria Pulmonar/metabolismo , Estrés Oxidativo , Hipoxia/complicaciones , Hipoxia/genética , Hipoxia/metabolismo , Inflamación/metabolismo , Citocinas/genética , Citocinas/metabolismo , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/genética , Apnea Obstructiva del Sueño/metabolismo , Proliferación Celular/genética , Miocitos del Músculo Liso/metabolismo
12.
Small ; 19(47): e2303963, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37488694

RESUMEN

Aqueous Zn-ion batteries (AZIBs) attract intensive attention owing to their environmental friendliness, cost-effectiveness, innate safety, and high specific capacity. However, the practical applications of AZIBs are hindered by several adverse phenomena, including corrosion, Zn dendrites, and hydrogen evolution. Herein, a Zn anode decorated with a 3D porous-structured Na3 V2 (PO4)3 (NVP@Zn) is obtained, where the NVP reconstruct the electrolyte/anode interface. The resulting NVP@Zn anode can provide a large quantity of fast and stable channels, facilitating enhanced Zn ion deposition kinetics and regulating the Zn ions transport process through the ion confinement effect. The NASICON-type NVP protective layer promote the desolvation process due to its nanopore structure, thus effectively avoiding side reactions. Theoretical calculations indicate that the NVP@Zn electrode has a higher Zn ion binding energy and a higher migration barrier, which demonstrates that NVP protective layer can enhance Zn ion deposition kinetics and prevent the unfettered 2D diffusion of Zn ions. Therefore, the results show that NVP@Zn/MnO2 full cell can maintain a high specific discharge capacity of 168 mAh g-1 and a high-capacity retention rate of 74.6% after cycling. The extraordinary results obtained with this strategy have confirmed the promising applications of NVP in high-performance AZIBs.

13.
Crit Rev Food Sci Nutr ; 63(14): 2216-2230, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-34491124

RESUMEN

As a notorious food-borne pathogen, Staphylococcus aureus can readily cause diseases in humans via contaminated food. Biofilm formation on various surfaces can increase the capacity of viable S. aureus cells for self-protection due to the stubborn structure of the biofilm matrix. Increased disease risk and economic losses caused by biofilm contamination in the food industry necessitate the urgent development of effective strategies for the inhibition and removal of S. aureus biofilms. Natural products have been extensively used as important sources of "eco-friendly" antibiofilm agents to avoid the side effects of conventional strategies on human health and the environment. This review discusses biofilm formation of S. aureus in food industries and focuses on providing an overview of potential promising target-oriented natural products and their mechanisms of S. aureus biofilm inhibition or removal. Hoping to provide valuable information of attractive research targets or potential undeveloped targets to screen potent natural anti-biofilm agents in food industries.


Asunto(s)
Infecciones Estafilocócicas , Staphylococcus aureus , Humanos , Antibacterianos/farmacología , Biopelículas
14.
J Org Chem ; 88(23): 16598-16608, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37948397

RESUMEN

An effective method for accessing diverse difluoroalkylated pyrrolo[1,2-a]indolediones via visible-light-induced PhI(OAc)2-promoted cascade difluoroalkylation/cyclization reaction under mild conditions has been established. This method is noteworthy for its use of DMSO-H2O as a green medium at room temperature and avoidance of photocatalysts. The reactions are straightforward to execute and convenient to expand on, provide good to excellent yields, and have good functional group tolerance.

15.
Nanotechnology ; 34(46)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37549662

RESUMEN

Via first-principles computational modeling and calculations, we propose a new class of two-dimensional (2D) atomically thin crystals that contain metal-C3(MC3) moieties periodically distributed in a graphenic lattice, which we refer to as 2D graphitic metal carbides (g-MCs). Most g-MCs are dynamically stable as verified by the calculated phonon spectra. Our detailed chemical bonding analyzes reveal that the high stability of g-MCs can be attributed to a unique bonding feature, which manifests as the carbon-backbone-mediated metal-metal interactions. These analyzes provide new insights for understanding the stability of 2D materials. It is found that the calculated electronic band gaps and magnetic moments (per unit cell) of g-MCs can range from 0 to 1.30 eV and 0 to 4.40µB, respectively. Highly tunable electronic properties imply great potential of 2D g-MCs in various applications. As an example, we show that 2D g-MnC can be an excellent electrocatalyst towards CO2reductive reaction for the formation of formic acid with an exceptionally high loading of Mn atoms (∼43 wt%). We expect this work to simulate new experiments for fabrication and applications of g-MCs.

16.
Appl Microbiol Biotechnol ; 107(2-3): 867-879, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36585511

RESUMEN

Biofilm-forming Staphylococcus aureus can easily accumulate on various food contact surfaces which induce cross-contamination and are difficult to eliminate in the food industry. This study aimed to evaluate the anti-biofilm effects of natural product biochanin A against S. aureus. Results showed that biochanin A effectively eradicated established S. aureus biofilms on different food-contact materials. Fluorescence microscopic analyses suggested that biochanin A disintegrated the established biofilms by dissociate extracellular polymeric substance (EPS) in matrix. In addition, biochanin A at the sub-MIC concentration also effectively inhibited the biofilm formation by regulating the expression of biofilm-related genes (icaA, srtA, eno) and suppressing the release of EPS in biofilm matrix. Molecular docking also demonstrated that biochanin A conducted strong interactions with biofilm-related proteins (Ica A, Sortase A, and Enolase). These findings demonstrated that biochanin A has the potential to be developed as a potent agent against S. aureus biofilm in food industries. KEY POINTS: • Anti-biofilm effect of biochanin A against S. aureus was revealed for the first time. • Biofilm of S. aureus on various food-contact surfaces were efficiently eradicated. • Biochanin A prevented S. aureus biofilm formation via reducing EPS production.


Asunto(s)
Matriz Extracelular de Sustancias Poliméricas , Staphylococcus aureus , Simulación del Acoplamiento Molecular , Biopelículas , Antibacterianos/farmacología
17.
J Sep Sci ; 46(10): e2200969, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36932879

RESUMEN

A novel chiral group functionalized metal-organic framework, Cyclodextrin-NH-MIL-53, was synthesized and modified on the inner wall of a capillary column via a post-synthetic process. The prepared chiral metal-organic framework was utilized as a chiral capillary stationary phase and used in an open-tubular capillary electrochromatography method to enantioseparate several racemic amino acids. Excellent enantioseparation of five pairs of enantiomers was obtained in this chiral separation system (Resolutions of D/L-Alanine = 16.844, D/L-Cysteine = 3.617, D/L-Histidine = 9.513, D/L-Phenylalanine = 8.133, and D/L-Tryptophan = 2.778). The prepared Cyclodextrin-NH-MIL-53 and the Cyclodextrin-NH-MIL-53-based capillary columns were characterized by scanning electron microscopy, X-ray diffraction, Fourie-transform infrared spectroscopy, and circular dichroism. The chiral capillary electrochromatography conditions, such as separation conditions, amount of Cyclodextrin-NH-MIL-53, and electroosmotic flow, were optimized. This research is estimated to present a novel insight and method for the design and use of metal-organic framework-based capillaries for enantioseparation.

18.
Ecotoxicol Environ Saf ; 267: 115616, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37871386

RESUMEN

Many studies have showed that phthalates have reproductive and embryonic toxicity, while the potential mechanisms are mostly unknown. Inflammation may play a mediating part in phthalate exposure and adverse reproductive endpoints. A cross-sectional survey was conducted to investigate the associations of phthalate metabolites with inflammatory cytokines in the follicular fluid (FF) of women undergoing in vitro fertilization (IVF). We determined the levels of eight phthalate metabolites and five cytokines in the FF of 76 women, including interleukin (IL)- 6, IL-8, IL-10, monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-α (TNF-α). The associations of individual phthalate exposure with cytokines in FF samples were explored by multiple linear regression. We further evaluated the combined effects of multiple phthalate exposures on FF levels of cytokines by using Bayesian kernel machine regression (BKMR) models. We found that there was a positive relationship between mono-ethyl phthalate (MEP) and IL-6 in the FF (percent change:12.4%; 95% CI: 1.3%, 24.9%). In contrast, elevated mono-benzyl phthalate (MBzP), mono(2-ethylhexyl) phthalate (MEHP) and %MEHP levels were associated with decreased MCP-1. In the BKMR models, phthalate metabolite mixtures were positively associated with TNF-α when the mixtures were lower than 65th percentile compared with their medians. In the stratified analyses, MEHP was inversely associated with MCP-1 among women with BMI ≥ 23 kg/m2 (test for interaction <0.05). Our results suggest that certain phthalate metabolites or their mixtures may alter levels of inflammatory cytokines in the FF, and further research is necessary to elucidate the mechanisms underlying the relationship between phthalates exposure, ovarian dysfunction and adverse pregnancy outcomes.


Asunto(s)
Citocinas , Factor de Necrosis Tumoral alfa , Embarazo , Femenino , Humanos , Teorema de Bayes , Estudios Transversales , Líquido Folicular , Interleucina-6 , Fertilización In Vitro
19.
Phytother Res ; 37(12): 5932-5946, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37697496

RESUMEN

BACKGROUND AND AIM: Acute myocardial infarction (AMI) is a multifactorial disease with high mortality rate worldwide. Ethanol extract of Pueraria lobata (EEPL) has been widely used in treating cardiovascular diseases in China. This study aimed to explore the underlying therapeutic mechanism of EEPL in AMI rats. EXPERIMENTAL PROCEDURE: We first evaluated the anti-AMI efficacy of EEPL through immunohistochemistry staining and biochemical indexes. Then, UPLC-MS/MS, 16S rDNA, and shotgun metagenomic sequencing were used to analyze the alterations in bile acid metabolism and intestinal flora. Finally, the influence of EEPL on ilem bile acid metabolism, related enzymes expression, and transporter proteins expression in rats were verified by mass spectrometry image and ELISA. KEY RESULTS: The results showed that EEPL can reduce cardiac impairment in AMI rats. Besides, EEPL effectively increased bile acid levels and regulated gut microbiota disturbance in AMI rats via increasing CYP7A1 expression and restoring intestinal microbiota diversity, separately. Moreover, it can increase bile acids reabsorption and fecal excretion through inhibiting FXR-FGF15 signaling pathway and increasing OST-α expression, which associated with Lachnoclostridium. CONCLUSIONS AND IMPLICATIONS: Our findings demonstrated that EEPL alleviated AMI partially by remediating intestinal dysbiosis and promoting bile acid biosynthesis, which provided new targets for AMI treatment.


Asunto(s)
Microbioma Gastrointestinal , Infarto del Miocardio , Pueraria , Ratas , Animales , Etanol , Cromatografía Liquida , Espectrometría de Masas en Tándem , Infarto del Miocardio/tratamiento farmacológico , Extractos Vegetales/farmacología , Ácidos y Sales Biliares
20.
J Asian Nat Prod Res ; 25(1): 53-60, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35446749

RESUMEN

Two new sesquiterpenoids (1 and 3), one new natural product (2), and two known compounds (4 and 5) were isolated from the leaves of Chimonanthus nitens. Their structures were elucidated by spectroscopic analysis, and the absolute configuration of compound 3 was determined by the X-ray single-crystal diffraction analysis. The cytotoxicity of compounds 1-5 was evaluated at three concentrations on two human breast cancer cell lines (MDA-MB-468 and MDA-MB-231) by MTT assay. As a result, we found that the cytotoxicity was weak even with a concentration of these compounds up to 100 µM.


Asunto(s)
Calycanthaceae , Medicamentos Herbarios Chinos , Sesquiterpenos , Humanos , Hojas de la Planta/química , Medicamentos Herbarios Chinos/química , Calycanthaceae/química , Sesquiterpenos/farmacología , Estructura Molecular
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