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1.
J Nat Prod ; 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-39388644

RESUMEN

Vancomycin-resistant Enterococcus (VRE) is an important nosocomial opportunistic pathogen that is associated with multidrug resistance. Here, we demonstrate that morellic acid inhibits VRE by restoring its sensitivity to vancomycin and ampicillin with low drug resistance and efficient biofilm clearance effects. Morellic acid binds to inner membrane phospholipids, such as phosphatidylethanolamine (PE), phosphatidylglycerol (PG), and cardiolipin (CL) of VRE, such that the fluidity and proton-motive force (PMF) interfere with the damaged inner membrane, causing intracellular reactive oxygen species (ROS) accumulation and bacterial death. Transcriptional analyses supported this effect on inner membrane-related pathways such as fatty acid biosynthesis and glycerophospholipid metabolism. Moreover, morellic acid significantly eliminated residual bacteria in the spleen, liver, kidneys, and abdominal effusion in mice. Our findings indicate the potential applications of morellic acid as an antibacterial agent or adjuvant for treating VRE infections.

2.
Eur J Med Chem ; 280: 116940, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39388902

RESUMEN

Mixed infections caused by drug-resistant bacteria and fungi pose a severe threat to human health, and multi-target drugs may provide an effective approach to combat drug-resistant pathogens. Therefore, this study aimed to investigate the efficacies of some oleanolic acid (OA) derivatives against multidrug-resistant (MDR) bacteria and fungi using in vitro and in vivo experiments. Novel amphiphilic OA derivatives were designed and optimised, in which compounds G1 and J1 exhibited effective antimicrobial activity (MICs = 1-2 µg/mL), high selectivity against MDR strains, rapid bactericidal activity, and good predictive pharmacokinetics. Mechanistically, both compounds prevented drug resistance by disrupting the bacterial cell membrane, inserting into the DNA, and binding to DNA gyrase. Additionally, J1 reduced microbial count in a mouse MRSA skin infection model and accelerated wound healing much better than vancomycin. Conclusively, this study presents a new class of potential drugs for resistant bacteria and fungi.

3.
Molecules ; 29(19)2024 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-39407562

RESUMEN

Three novel ent-kaurane diterpenes, namely sigesbeckin A-C (1-3), in conjunction with eight previously identified analogues (4-11), were isolated from Sigesbeckia orientalis. Their chemical structures were resolved through multiple spectroscopic analyses. All compounds were assessed for antimicrobial bioactivity against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE) strains. In particular, compounds 1 and 5 demonstrated moderate efficacy, with MIC values of 64 µg/mL. Moreover, compounds 3, 5, and 11 were found to synergize with doxorubicin hydrochloride (DOX) and vancomycin (VAN) against MRSA and VRE. The aforementioned findings offer valuable insights for the development of novel alternatives to antibiotics, which can effectively tackle the escalating issue of antibiotic resistance.


Asunto(s)
Antibacterianos , Diterpenos de Tipo Kaurano , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Diterpenos de Tipo Kaurano/farmacología , Diterpenos de Tipo Kaurano/química , Diterpenos de Tipo Kaurano/aislamiento & purificación , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Asteraceae/química , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología , Vancomicina/farmacología , Vancomicina/química , Doxorrubicina/farmacología , Sinergismo Farmacológico , Sigesbeckia
4.
J Ethnopharmacol ; 337(Pt 1): 118805, 2024 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-39251150

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Caryopteris trichosphaera W. W. Sm., a traditional ethnic medicine, was recorded in the Compendium of Materia Medica for treating wound infection by pathogenic infection. However, its antibacterial potential and bioactive compositions against drug-resistant bacteria need to be validated. AIM OF THE STUDY: To investigate the chemical constituents of C. trichosphaera and explore its anti-MRSA component in vitro and in vivo, together with the antibacterial mechanism. MATERIALS AND METHODS: Bioactive constituents investigation was carried out by phytochemical method and antibacterial screening. The antibacterial mechanism was predicted by network pharmacology, which was further validated by time-kill analysis, membrane function tests, multigenerational resistance induction assay and biofilm test, and metabolomics analysis in vitro. In addition, MRSA-induced epidermal infection in mice was selected to evaluate its pharmacological effect in vivo. RESULTS: Six antibacterial diterpenoids against MRSA and VRE with MIC values 4-32 µg/mL from C. trichosphaera were reported for the first time, in which the major compound cativic acid (1) disrupted MRSA cell membranes by modulating permeability, depolarization, and fluidity while increasing reactive oxygen species (ROS) and malondialdehyde (MDA) levels. It also displayed remarkable anti-biofilm activity without inducing bacterial resistance or cytotoxicity. Moreover, cativic acid affected MRSA biosynthesis of cofactors, amino acid biosynthesis, nucleotide metabolism by metabolomics analysis. Furthermore, cativic acid accelerated wound healing in MRSA-infected mouse skin wounds, even better than vancomycin. CONCLUSIONS: The results supported the traditional use of C. trichosphaera, and presented unreported anti-MRSA agent, cativic acid, as a plant-derived bactericide in vitro and in vivo for the first time.

5.
J Control Release ; 375: 467-477, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39293527

RESUMEN

Bacterial infections result in 7,700,000 deaths per year globally, with intracellular bacteria causing repeated and resistant infection. No drug is currently licenced for the treatment of intracellular bacteria. A new screening platform mimicking the host milieu has been established to explore phytochemical antibiotic adjuvants. Previously neglected isoprenylated flavonoids were found to be effective against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Specifically, the synergistic effect between glabrol and streptomycin against intracellular bacteria was observed for the first time. The glabrol-streptomycin combination targets bacterial inner membrane phospholipids, disrupts arginine biosynthesis, inhibits cell wall proteins and biofilm formation genes (agrA/B/C/D), and promotes ROS production, causing subsequent membrane and wall damage. To enhance the selective uptake of combination drug into infected cells, hyaluronic acid-streptomycin-lipoic acid-glabrol nanoparticles (HSLGS-S) were designed and synthesized to trigger the intracellular delivery of the glabrol-streptomycin combination. Thus, the treatment can be transported into the infected intracellular region and selectively release the glabrol-streptomycin combination to the bacterial at site. The bioactivity of HSLGS-S in clearing intracellular bacteria was 20-fold higher than that of the glabrol-streptomycin combination alone in vitro and 2- to 10-fold higher in vivo.


Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana Múltiple , Estreptomicina , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Animales , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Estreptomicina/farmacología , Estreptomicina/administración & dosificación , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Ácido Tióctico , Nanopartículas , Humanos , Ácido Hialurónico , Femenino , Ratones Endogámicos BALB C , Biopelículas/efectos de los fármacos , Sinergismo Farmacológico
6.
Phytochemistry ; 228: 114241, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39122160

RESUMEN

Six pairs of previously undescribed enantiomeric phytocannabinoid-like meroterpenoids, (±)-spinulinoids A‒F, and two naturally occurring compounds, (+)-rhododaurichromanic acid A and (E)-4-((3,7-dimethylocta-2,6-dien-1-yl)oxy)benzoic acid, together with one known congener, (-)-rhododaurichromanic acid A, were obtained from the twigs and leaves of Rhododendron spinuliferum. Their structures were established by their extensive spectral data (NMR and HRESIMS), ECD calculations, and single-crystal X-ray diffraction data. Spinulinoids A and B are unprecedented phytocannabinoid-like meroterpenoids constructed by the resorcinol moiety and a ß-bisabolene unit, whereas spinulinoid C represents a rare adduct of quinone and ß-bisabolene with a tricyclic 6/6/6 ring system.


Asunto(s)
Hojas de la Planta , Rhododendron , Terpenos , Rhododendron/química , Hojas de la Planta/química , Terpenos/química , Terpenos/aislamiento & purificación , Estructura Molecular , Modelos Moleculares , Conformación Molecular , Cristalografía por Rayos X
7.
ACS Infect Dis ; 10(9): 3430-3439, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39185798

RESUMEN

Vancomycin-resistant enterococcus (VRE) is a major nosocomial pathogen that exhibits enhanced infectivity due to its robust virulence and biofilm-forming capabilities. In this study, 6-methoxyldihydrochelerythrine chloride (6-MDC) inhibited the growth of exponential-phase VRE and restored VRE's sensitivity to vancomycin. 6-MDC predominantly suppressed the de novo biosynthetic pathway of pyrimidine and purine in VRE by the RNA-Seq analysis, resulting in obstructed DNA synthesis, which subsequently weakened bacterial virulence and impeded intracellular survival. Furthermore, 6-MDC inhibited biofilm formation, eradicated established biofilms, reduced virulence, and enhanced the host immune response to prevent intracellular survival and replication of VRE. Finally, 6-MDC reduced the VRE load in peritoneal fluid and cells significantly in a murine peritoneal infection model. This paper provides insight into the potential antimicrobial target of benzophenanthridine alkaloids for the first time.


Asunto(s)
Antibacterianos , Benzofenantridinas , Biopelículas , Pruebas de Sensibilidad Microbiana , Enterococos Resistentes a la Vancomicina , Animales , Ratones , Antibacterianos/farmacología , Antibacterianos/química , Benzofenantridinas/farmacología , Benzofenantridinas/química , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Biopelículas/efectos de los fármacos , Virulencia/efectos de los fármacos , Vancomicina/farmacología , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/microbiología , Humanos , Femenino
8.
Eur J Med Chem ; 277: 116714, 2024 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-39096819

RESUMEN

The abuse of antibiotics leads to the rapid spread of bacterial resistance, which seriously threatens human life and health. Now, 8 resorcylic acid derivatives, including 4 new compounds (1-4) were isolated from Lysimachia tengyuehensis by bio-guided isolation, and they inhibited both methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) (MIC = 4-8 µg/mL). Notably, 1 and 2 rapidly killed MRSA and VRE within 40 min without drug resistance in 20 days. Mechanically, they potently disrupted biofilm and cell membrane by interfering with bacterial metabolic imbalance. The structure-activity relationship (SAR) revealed that the lipophilic long carbon chains (C-5/C-6) and hydrophilic hydroxyl/carboxyl groups were essential for the anti-MRSA and VRE bioactivity. Additionally, they effectively recovered MRSA-infected skin wounds and VRE-infected peritoneal in vivo. Resorcylic acid derivatives showed significant anti-MRSA and VRE bioactivity in vitro and in vivo with potential application for the first time.


Asunto(s)
Antibacterianos , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Primulaceae , Enterococos Resistentes a la Vancomicina , Animales , Humanos , Ratones , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Biopelículas/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Lysimachia , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Estructura Molecular , Primulaceae/química , Relación Estructura-Actividad , Enterococos Resistentes a la Vancomicina/efectos de los fármacos
9.
J Nat Prod ; 87(8): 2004-2013, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39033408

RESUMEN

Seven new formononetin derivatives (1-7) were designed and prepared from formononetin (phase II phytoestrogen). The derivatives 9-butyl-3-(4-methoxyphenyl)-9,10-dihydro-4H,8H-chromeno[8,7-e][1,3]oxazin-4-one (2) and 9-(furan-3-ylmethyl)-3-(4-methoxyphenyl)-9,10-dihydro-4H,8H-chromeno[8,7-e][1,3]oxazin-4-one (7) promoted significant osteoblast formation by modulating the BMP/Smad pathway. Compound 7 exhibited potent antiosteoclastogenesis activity in RANKL-induced RAW264.7 cells and ovariectomy (OVX)-induced osteoporosis in mice by regulation of the RANK/RANKL/OPG pathway. Compound 7 regulated osteoblast and osteoclast simultaneously and showed better effect than the well-known drug ipriflavone in vivo, suggesting 7 as a patented antiosteoporosis candidate.


Asunto(s)
Isoflavonas , Osteoblastos , Osteoclastos , Osteoporosis , Ligando RANK , Isoflavonas/farmacología , Isoflavonas/química , Animales , Osteoblastos/efectos de los fármacos , Ratones , Osteoporosis/tratamiento farmacológico , Osteoclastos/efectos de los fármacos , Células RAW 264.7 , Ligando RANK/metabolismo , Ligando RANK/efectos de los fármacos , Femenino , Estructura Molecular , Ovariectomía , Osteoprotegerina
10.
J Ethnopharmacol ; 333: 118473, 2024 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-38897554

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Sarcococca hookeriana var. digyna Franch. has been widely utilized in folk medicine by the Miao people in the southwestern region of China for treating skin sores which may be associated with microbial infection. AIM OF THE STUDY: To investigate the antifungal bioactivity of S. hookeriana var. digyna against fluconazole-resistant Candida albicans in vitro and in vivo, as well as its underlying mechanism and the key bioactive component. MATERIALS AND METHODS: The antifungal bioactivity of 80% ethanol extract of S. hookeriana var. digyna (SHE80) was investigated in vitro using the broth microdilution method, time-growth curve, and time-kill assay. Its key functional component and antifungal mechanism were explored with combined approaches including UPLC-Q-TOF-MS, network pharmacology and metabolomics. The antifungal pathway was further supported via microscopic observation of fungal cell morphology and examination of its effects on fungal biofilm and cell membranes using fluorescent staining reagents. In vivo assessment of antifungal bioactivity was conducted using a mouse model infected with C. albicans on the skin. RESULTS: S. hookeriana var. digyna suppressed fluconazole-resistant C. albicans efficiently (MIC = 16 µg/mL, MFC = 64 µg/mL). It removed fungal biofilm, increased cell membrane permeability, induced protein leakage, reduced membrane fluidity, disrupted mitochondrial membrane potential, induced the release of reactive oxygen species, promoted cell apoptosis, and inhibited the transformation of fungi from the yeast state to the hyphal state significantly. In terms of mechanism, it affected sphingolipid metabolism and signaling pathway. Moreover, the predicted bioactive component, sarcovagine D, was supported by antifungal bioactivity evaluation in vitro (MIC = 4 µg/mL, MFC = 16 µg/mL). Furthermore, S. hookeriana var. digyna promoted wound healing, reduced the number of colony-forming units, and reduced inflammation effectively in vivo. CONCLUSIONS: The traditional use of S. hookeriana var. digyna for fungal skin infections was supported by antifungal bioactivity investigated in vitro and in vivo. Its mechanism and bioactive component were predicted and confirmed by experiments, which also provided a new antifungal agent for future research.


Asunto(s)
Antifúngicos , Biopelículas , Candida albicans , Farmacorresistencia Fúngica , Fluconazol , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Antifúngicos/farmacología , Antifúngicos/aislamiento & purificación , Candida albicans/efectos de los fármacos , Animales , Fluconazol/farmacología , Farmacorresistencia Fúngica/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Ratones , Biopelículas/efectos de los fármacos , Candidiasis/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Femenino , Potencial de la Membrana Mitocondrial/efectos de los fármacos
11.
J Colloid Interface Sci ; 672: 75-85, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38833736

RESUMEN

Carbon dioxide (CO2) electroreduction provides a sustainable route for realizing carbon neutrality and energy supply. Up to now, challenges remain in employing abundant and inexpensive nickel materials as candidates for CO2 reduction due to their low activity and favorable hydrogen evolution. Here, the representative iron-modified nickel nanoparticles embedded in nitrogen-doped carbon (Ni1-Fe0.125-NC) with the porous botryoid morphology were successfully developed. Hexamethylenetetramine is used as nitrogen-doped carbon source. The collaboration of internal lattice expansion with electron effect and external confinement effect with size effect endows the significant enhancement in electrocatalytic CO2 reduction. The optimized Ni1-Fe0.125-NC exhibits broad potential ranges for continuous carbon monoxide (CO) production. A superb CO Faradaic efficiency (FECO) of 85.0 % realized at -1.1 V maintains a longtime durability over 35 h, which exceeds many state-of-the-art metal catalysts. Theoretical calculations further confirm that electron redistribution promotes the desorption of CO in the process for favorable CO production. This work opens a new avenue to design efficient nickel-based materials by considering the intrinsic structure and external confinement for CO2 reduction.

12.
Int J Nanomedicine ; 19: 4181-4197, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38766656

RESUMEN

Purpose: The committed differentiation fate regulation has been a difficult problem in the fields of stem cell research, evidence showed that nanomaterials could promote the differentiation of stem cells into specific cell types. Layered double hydroxide (LDH) nanoparticles possess the regulation function of stem cell fate, while the underlying mechanism needs to be investigated. In this study, the process of embryonic stem cells (ESCs) differentiate to neural progenitor cells (NPCs) by magnesium aluminum LDH (MgAl-LDH) was investigated. Methods: MgAl-LDH with diameters of 30, 50, and 100 nm were synthesized and characterized, and their effects on the cytotoxicity and differentiation of NPCs were detected in vitro. Dot blot and MeRIP-qPCR were performed to detect the level of m6A RNA methylation in nanoparticles-treated cells. Results: Our work displayed that LDH nanoparticles of three different sizes were biocompatible with NPCs, and the addition of MgAl-LDH could significantly promote the process of ESCs differentiate to NPCs. 100 nm LDH has a stronger effect on promoting NPCs differentiation compared to 30 nm and 50 nm LDH. In addition, dot blot results indicated that the enhanced NPCs differentiation by MgAl-LDH was closely related to m6A RNA methylation process, and the major modification enzyme in LDH controlled NPCs differentiation may be the m6A RNA methyltransferase METTL3. The upregulated METTL3 by LDH increased the m6A level of Sox1 mRNA, enhancing its stability. Conclusion: This work reveals that MgAl-LDH nanoparticles can regulate the differentiation of ESCs into NPCs by increasing m6A RNA methylation modification of Sox1.


Asunto(s)
Diferenciación Celular , Nanopartículas , Células-Madre Neurales , Diferenciación Celular/efectos de los fármacos , Animales , Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Ratones , Nanopartículas/química , Metilación/efectos de los fármacos , Hidróxidos/química , Hidróxidos/farmacología , Metiltransferasas/metabolismo , Metiltransferasas/genética , Tamaño de la Partícula , Células Madre Embrionarias/efectos de los fármacos , Células Madre Embrionarias/citología , Adenosina/farmacología , Adenosina/química , Adenosina/análogos & derivados , Hidróxido de Aluminio/química , Hidróxido de Aluminio/farmacología , Hidróxido de Magnesio/química , Hidróxido de Magnesio/farmacología
13.
J Ethnopharmacol ; 331: 118327, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750987

RESUMEN

ETHNOPHARMACOLOGY RELEVANCE: Rohdea pachynema F.T.Wang & Tang (R. pachynema), is a traditional folk medicine used for the treatment of stomach pain, stomach ulcers, bruises, and skin infections in China. Some of the diseases may relate to microbial infections in traditional applications. However few reports on its antimicrobial properties and bioactive components. AIM OF THE STUDY: To identify its bioactive constituents against methicillin-resistant Staphylococcus aureus (MRSA) in vitro and in vivo, and its mechanism. MATERIALS AND METHODS: The anti-MRSA ingredient 6α-O-[ß-D-xylopyranosyl-(1 â†’ 3)-ß-D-quinovopyranosyl]-(25S)-5α-spirostan-3ß-ol (XQS) was obtained from R. pachynema by phytochemical isolation. Subsequently, XQS underwent screening using the broth microdilution method and growth inhibition curves to assess its antibacterial activity. The mechanism of XQS was evaluated by multigeneration induction, biofilm resistance assay, scanning electron microscopy, transmission electron microscopy, and metabolomics. Additionally, a mouse skin infection model was established in vivo. RESULTS: 26 compounds were identified from the R. pachynema, in which anti-MRSA spirostane saponin (XQS) was reported for the first time with a minimum inhibitory concentration (MIC) of 8 µg/mL. XQS might bind to peptidoglycan (PGN) of the cell wall, phosphatidylglycerol (PG), and phosphatidylethanolamine (PE) of the cell membrane, then destroying the cell wall and the cell membrane, resulting in reduced membrane fluidity and membrane depolarization. Furthermore, XQS affected MRSA lipid metabolism, amino acid metabolism, and ABC transporters by metabolomics analysis, which targeted cell walls and membranes causing less susceptibility to drug resistance. Furthermore, XQS (8 mg/kg) recovered skin wounds in mice infected by MRSA effectively, superior to vancomycin (8 mg/kg). CONCLUSIONS: XQS showed anti-MRSA bioactivity in vitro and in vivo, and its mechanism association with cell walls and membranes was reported for the first, which supported the traditional uses of R. pachynema and explained its sensitivity to MRSA.


Asunto(s)
Antibacterianos , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Saponinas , Animales , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/aislamiento & purificación , Ratones , Saponinas/farmacología , Saponinas/aislamiento & purificación , Espirostanos/farmacología , Espirostanos/aislamiento & purificación , Biopelículas/efectos de los fármacos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Femenino , Peces , Masculino
14.
Eur J Med Chem ; 271: 116401, 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38640870

RESUMEN

Methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) cause more than 100,000 deaths each year, which need efficient and non-resistant antibacterial agents. SAR analysis of 162 flavonoids from the plant in this paper suggested that lipophilic group at C-3 was crucial, and then 63 novel flavonoid derivatives were designed and total synthesized. Among them, the most promising K15 displayed potent bactericidal activity against clinically isolated MRSA and VRE (MICs = 0.25-1.00 µg/mL) with low toxicity and high membrane selectivity. Moreover, mechanism insights revealed that K15 avoided resistance by disrupting biofilm and targeting the membrane, while vancomycin caused 256 times resistance against MRSA, and ampicillin caused 16 times resistance against VRE by the same 20 generations inducing. K15 eliminated residual bacteria in mice skin MRSA-infected model (>99 %) and abdominal VRE-infected model (>92 %), which was superior to vancomycin and ampicillin.


Asunto(s)
Antibacterianos , Flavonoides , Staphylococcus aureus Resistente a Meticilina , Pruebas de Sensibilidad Microbiana , Enterococos Resistentes a la Vancomicina , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Flavonoides/farmacología , Flavonoides/química , Flavonoides/síntesis química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Enterococos Resistentes a la Vancomicina/efectos de los fármacos , Animales , Ratones , Relación Estructura-Actividad , Estructura Molecular , Relación Dosis-Respuesta a Droga , Infecciones Estafilocócicas/tratamiento farmacológico , Humanos
15.
Small Methods ; 8(8): e2301283, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38509851

RESUMEN

Bone tissue defects present a major challenge in orthopedic surgery. Bone tissue engineering using multiple versatile bioactive materials is a potential strategy for bone-defect repair and regeneration. Due to their unique physicochemical and mechanical properties, biofunctional materials can enhance cellular adhesion, proliferation, and osteogenic differentiation, thereby supporting and stimulating the formation of new bone tissue. 3D bioprinting and physical stimuli-responsive strategies have been employed in various studies on bone regeneration for the fabrication of desired multifunctional biomaterials with integrated bone tissue repair and regeneration properties. In this review, biomaterials applied to bone tissue engineering, emerging 3D bioprinting techniques, and physical stimuli-responsive strategies for the rational manufacturing of novel biomaterials with bone therapeutic and regenerative functions are summarized. Furthermore, the impact of biomaterials on the osteogenic differentiation of stem cells and the potential pathways associated with biomaterial-induced osteogenesis are discussed.


Asunto(s)
Materiales Biocompatibles , Regeneración Ósea , Huesos , Osteogénesis , Ingeniería de Tejidos , Ingeniería de Tejidos/métodos , Osteogénesis/efectos de los fármacos , Humanos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Regeneración Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Andamios del Tejido/química , Animales , Impresión Tridimensional , Bioimpresión/métodos
16.
ChemSusChem ; 17(16): e202400189, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-38504639

RESUMEN

Due to the larger sizes and stronger positive polarity of Zn2+ than dominant univalent ions, Zn2+ sluggish diffusion within V2O5 host electrodes is an essential issue in developing aqueous zinc-ion batteries (ZIBs) of higher energy densities. Herein, a high-performance V2O5 cathode was developed through subtly synthesizing and tuning V2O5 with oxygen vacancies-enriched and elongated apical V=O1 bond by altering the gradient concentration of hydrazine hydrate in the gas-solid reaction system. This strategy can enhance both intrinsic and extrinsic conductivity to a large extent. The electrochemical testing demonstrated the oxygen vacancies-enriched and elongated apical V=O1 bond can not only increase the intrinsic electronic conductivity of V2O5, but also induce additional pseudocapacitance to enhance the Zn2+ diffusion kinetics. We used infrared spectroscopy and Raman spectroscopy to characterize the change in the bond length structure of V2O5. Simultaneously, the long-term cyclability (capacity retention of 76.9 % after 1200 cycles at 4.0 A g-1) and rate capabilities (218 mAh g-1 at 4.0 A g-1) are promoted as well. We believe that our work might shed light on the bond length engineering of V2O5 and provide insights for the reasonable designing of novel cathodes for practical rechargeable ZIBs.

17.
ACS Appl Mater Interfaces ; 16(6): 7152-7160, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38294350

RESUMEN

Severe CO2 emissions has posed an increasingly alarming threat, motivating the development of efficient CO2 capture materials, one of the key parts of carbon capture, utilization, and storage (CCUS). In this study, a series of metal-organic frameworks (MOFs) named Sc-X (X = S, M, L) were constructed inspired by recorded MOFs, Zn-BPZ-SA and MFU-4l-Li. The corresponding isoreticular double-interpenetrating MOFs (Sc-X-IDI) were subsequently constructed via the introduction of isoreticular double interpenetration. Grand canonical Monte Carlo (GCMC) simulations were adopted at 298 K and 0.1-1.0 bar to comprehensively evaluate the CO2 capture and separation performances in Sc-X and Sc-X-IDI, with gas distribution, isothermal adsorption heat (Qst), and van der Waals (vdW)/Coulomb interactions. It is showed that isoreticular double interpenetration significantly improved the interactions between adsorbed gases and frameworks by precisely modulating pore sizes, particularly observed in Sc-M and Sc-M-IDI. Specifically, the Qst and Coulomb interactions exhibited a substantial increase, rising from 28.38 and 22.19 kJ mol-1 in Sc-M to 43.52 and 38.04 kJ mol-1 in Sc-M-IDI, respectively, at 298 K and 1.0 bar. Besides, the selectivity of CO2 over CH4/N2 was enhanced from 55.36/107.28 in Sc-M to 3308.61/7021.48 in Sc-M-IDI. However, the CO2 capture capacity is significantly influenced by the pore size. Sc-M, with a favorable pore size, exhibits the highest capture capacity of 15.86 mmol g-1 at 298 K and 1.0 bar. This study elucidated the impact of isoreticular double interpenetration on the CO2 capture performance in MOFs.

18.
Heliyon ; 10(1): e22963, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38163185

RESUMEN

Zanthoxylum motuoense (Tibetan prickly ash, MTHJ), different from the Chinese prickly ash species, is distributed only in the Tibet. Now the chemical characterization and antibacterial activity of MTHJ extracts were analyzed for the first time. As a result, Schinifoline (12), γ-Fagarine (8), (2E,7E,9E)-6 S-Hydroxy-N-(2-methylpropyl)-11-oxo-2, 7, 9-Dodecatrienamide (6), and Neoechinulin A (17) were found to be the major different factors by untarget LC-MS metabolomics together with quantitative analysis on target. These four compounds were also the major antibacterial constituents. Then, the antimicrobial activity of MTHJ fractions was evaluated with colony forming units (CFU), fluorescence microscopy imaging, SEM and investigating the potential food preservation. Nutritional composition, colour and sensory evaluation of extract-treated samples were evaluated along storage time. The results suggested the MTHJ may be used for meat products preservation, and the scores were significantly higher for its unique flavor, which offered a promising choice for food safety, preservation and reducing foodborne illness.

19.
Res Vet Sci ; 166: 105080, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37952298

RESUMEN

This study aimed to investigate the effects of supplementing laying hen diets with Radix Isatidis Polysaccharide (RIPS) on egg quality, immune function, and intestinal health. The research was conducted using 288 Hyland Brown hens, which were randomly assigned to four dietary treatments: control (without RIPS), low dose (200 g/t), medium dose (500 g/t), and high dose (1000 g/t) of RIPS. Each dietary treatment was administered to eight replicates of nine hens for nine weeks. The results revealed that RIPS inclusion in diets significantly improved egg quality parameters such as egg shape index, yolk color, haugh unit, and protein height (P < 0.05). Additionally, RIPS supplementation enhanced immune function as evidenced by an alteration in serum biochemical parameters, an increase in the spleen index, and a decrease in the liver index. Further, an evaluation of intestinal health showed that RIPS fortified the intestinal barrier, thus increasing the population of beneficial intestinal bacteria and reducing the abundance of harmful ones. Such mechanisms promoted intestinal health, digestion, and nutrient absorption, ultimately leading to enhanced egg quality. In conclusion, supplementing laying hen diets with RIPS has been demonstrated to improve egg quality by boosting immunity and optimizing intestinal digestion and absorption.


Asunto(s)
Pollos , Suplementos Dietéticos , Animales , Femenino , Dieta/veterinaria , Inmunidad , Alimentación Animal/análisis
20.
J Colloid Interface Sci ; 657: 83-90, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38035422

RESUMEN

The development of non-precious metal electrocatalysts for oxygen evolution reaction (OER) is crucial for generating large-scale hydrogen through water electrolysis. In this work, bimetal phosphides embedded in electrospun carbon nanofibers (P-FeNi/CNFs) were fabricated through a reliable electrospinning-carbonization-phosphidation strategy. The incorporation of P-FeNi nanoparticles within CNFs prevented them from forming aggregation and further improved their electron transfer property. The bimetal phosphides helped to weaken the adsorption of O intermediate, promoting the OER activity, which was confirmed by the theoretical results. The as-prepared optimized P-Fe1Ni2/CNFs catalyst exhibited very high OER electrocatalytic performance, which required very low overpotentials of just 239 and 303 mV to reach 10 and 1000 mA cm-2, respectively. It is superior to the commercial RuO2 and many other related OER electrocatalysts reported so far. In addition, the constructed alkaline electrolyzer based on the P-Fe1Ni2/CNFs catalyst and Pt/C delivered a cell voltage of 1.52 V at 10 mA cm-2, surpassing the commercial RuO2||Pt/C (1.61 V) electrolyzer. It also offered excellent alkaline OER performance in simulated seawater electrolyte. This demonstrated its potential for practical applications across a broad range of environmental conditions. Our work provides new ideas for the ration design of highly efficient non-precious metal-based OER catalysts for water electrolysis.

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