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1.
Arch Microbiol ; 206(4): 146, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38462572

RESUMEN

Depression is a prevalent mental illness, affecting a significant portion of the global population. Recent research has highlighted the crucial role of the gut microbiota in both metabolic and central nervous health. By reviewing literature from various databases, including Pubmed, Science Direct, Web of Science, and Scopus, spanning the years 2005-2023, a comprehensive search was conducted using keywords such as "Depression" and "Gut Microbiota". The gut microbiota acts as a "second brain" in humans and can communicate bidirectionally with the brain through the Brain-gut-microbiota axis pathway. This communication involves the immune and nervous systems. However, there are challenges in detecting and treating depression effectively. To address these limitations, researchers have been exploring the relationship between gut microbiota and depression. Studies have shown that gut microbial metabolites, such as lipopolysaccharides and short-chain fatty acids, can induce pro-inflammatory cytokines that contribute to neuroinflammation and increase the risk of depression. The kynurenine pathway, triggered by gut microbial metabolites, has also been associated with neuroinflammation. Thus, investigating these microbial metabolites can provide insights into depression treatment. This review focuses on analyzing the connection between gut microbial metabolites, inflammation, and depression. It explores novel mechanisms contributing to depression, specifically focusing on the mediation of inflammation through the release of pro-inflammatory cytokines. The objective is to provide valuable insights into the mechanisms underlying depression and to propose potential treatments.


Asunto(s)
Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/fisiología , Depresión , Enfermedades Neuroinflamatorias , Inflamación , Citocinas
2.
Angew Chem Int Ed Engl ; 63(26): e202406069, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38630112

RESUMEN

The construction of C(sp3)-N bonds via direct N-centered radical addition with olefins under benign conditions is a desirable but challenging strategy. Herein, we describe an organo-photocatalytic approach to achieve anti-Markovnikov alkene hydroamidation with sulfonyl azides in a highly efficient manner under transition-metal-free and mild conditions. A broad range of substrates, including both activated and unactivated alkenes, are suitable for this protocol, providing a convenient and practical method to construct sulfonylamide derivatives. A synergistic experimental and computational mechanistic study suggests that the additive, Hantzsch ester (HE), might undergo a triplet-triplet energy transfer manner to achieve photosensitization by the organo-photocatalyst under visible light irradiation. Next, the resulted triplet excited state 3HE* could lead to a homolytic cleavage of C4-H bond, which triggers a straightforward H-atom transfer (HAT) style in converting sulfonyl azide to the corresponding key amidyl radical. Subsequently, the addition of the amidyl radical to alkene followed by HAT from p-toluenethiol could proceed to afford the desired anti-Markovnikov hydroamidation product. It is worth noting that mechanistic pathway bifurcation could be possible for this reaction. A feasible radical chain propagation mechanistic pathway is also proposed to rationalize the high efficiency of this reaction.

3.
Angew Chem Int Ed Engl ; 63(16): e202317284, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38342760

RESUMEN

In this study, a series of enantioenriched sp3-Ge/B bimetallic modules were successfully synthesized via an enantioselective copper-catalyzed hydroboration of carbagermatrane (Ge)-containing alkenes. Orthogonal cross-coupling selectivity under different Pd-catalyzed conditions was achieved in an enantiospecific manner. Notably, the chiral secondary Ge exhibited a remarkable transmetallation ability prior to primary or secondary Bpin. The effectiveness of this Ge/B bimetallic strategy was further demonstrated through the development of new functional small molecules with Aggregation-Induced Emission (AIE) and Circularly Polarized Luminescence (CPL) performance. This represents the first successful example of synthesis of enantioenriched alkylgermanium reagents that permit enantiospecific cross-coupling reactions.

4.
J Am Chem Soc ; 2023 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-37933858

RESUMEN

Bioorthogonal decaging chemistry with both fast kinetics and high efficiency is highly demanded for in vivo applications but remains very sporadic. Herein, we describe a new bioorthogonal decaging chemistry between N-oxide and silylborane. A simple replacement of "C" in boronic acid with "Si" was able to substantially accelerate the N-oxide decaging kinetics by 106 fold (k2: up to 103 M-1 s-1). Moreover, a new N-oxide-masked self-immolative spacer was developed for the traceless release of various payloads upon clicking with silylborane with fast kinetics and high efficiency (>90%). Impressively, one such N-oxide-based self-assembled bioorthogonal nano-prodrug in combination with silylborane led to significantly enhanced tumor suppression effects as compared to the parent drug in a 4T1 mouse breast tumor model. In aggregate, this new bioorthogonal click-and-release chemistry is featured with fast kinetics and high efficiency and is perceived to find widespread applications in chemical biology and drug delivery.

5.
Nat Mater ; 21(5): 518-525, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35422509

RESUMEN

Spontaneous hierarchical self-organization of nanometre-scale subunits into higher-level complex structures is ubiquitous in nature. The creation of synthetic nanomaterials that mimic the self-organization of complex superstructures commonly seen in biomolecules has proved challenging due to the lack of biomolecule-like building blocks that feature versatile, programmable interactions to render structural complexity. In this study, highly aligned structures are obtained from an organic-inorganic mesophase composed of monodisperse Cd37S18 magic-size cluster building blocks. Impressively, structural alignment spans over six orders of magnitude in length scale: nanoscale magic-size clusters arrange into a hexagonal geometry organized inside micrometre-sized filaments; self-assembly of these filaments leads to fibres that then organize into uniform arrays of centimetre-scale bands with well-defined surface periodicity. Enhanced patterning can be achieved by controlling processing conditions, resulting in bullseye and 'zigzag' stacking patterns with periodicity in two directions. Overall, we demonstrate that colloidal nanomaterials can exhibit a high level of self-organization behaviour at macroscopic-length scales.


Asunto(s)
Nanoestructuras , Nanoestructuras/química
6.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(1): 114-121, 2023 Jan.
Artículo en Zh | MEDLINE | ID: mdl-36647653

RESUMEN

Objective: To investigate the prognostic value of the expression of myeloid leukemia factor 1-interacting protein (MLF1IP) in gastric cancer tissue and its regulatory role in tumor progression. Methods: Gene Expression Omnibus (GEO) database was used to analyze the expression level of MLF1IP in tumor tissues of gastric cancer patients. Kaplan-Meier Plotter database was used to analyze the relationship between MLF1IP expression level and patient prognosis. We conducted a retrospective analysis of 108 gastric cancer patients who had undergone radical surgery at our hospital between January 2015 and December 2015. The expression of MLF1IP in gastric cancer tissue and adjacent tissues was examined. We analyzed the relationship between MLF1IP and the clinicopathological parameters of gastric cancer patients and its impact on the long-term prognosis of gastric cancer patients. Univariate and multivariate regression analyses were done to identify the risk factors affecting the long-term prognosis of gastric cancer patients. The assessment value of MLF1IP for long-term prognosis of gastric cancer was analyzed with ROC curve. The effects of MLF1IP on the proliferation, migration, and invasion of gastric cancer cells were analyzed in vitro with gastric cancer cell line (MGC803). A xenograft tumor model was established with nude mice to analyze in vivo the effect of MLF1IP on tumor growth. Results: The results of the gastric cancer cohort GSE29272 of GEO database showed that the expression level of MLF1IP in gastric cancer tissues was significantly higher than that in normal tissues ( P<0.05). Analysis with Kaplan-Meier Plotter database indicated that high MLF1IP expression was correlated with poor prognosis in gastric cancer patients. Immunohistochemical analysis showed that the expression level of MLF1IP in gastric cancer tissues was higher than that in adjacent tissues ( P<0.05). Correlation analysis showed that the MLF1IP level in gastric cancer tissue was positively correlated with Ki67 ( r=0.609, P<0.01), peripheral blood carcinoembryonic antigen (CEA) ( r=0.572, P<0.01) and carbohydrate antigen 19-9 (CA19-9) ( r=0.623, P<0.01). Kaplan-Meier (K-M) survival analysis showed that the 5-year survival rate of patients in the MLF1IP high expression group was significantly lower than that in the MLF1IP low expression group ( P<0.01). Cox regression analysis showed that independent risk factors for 5-year survival after radical gastrectomy for gastric cancer included the expression of MLF1IP ( HR=2.508, 95% CI: 1.259-4.999), CEA≥5 µg/L ( HR=2.171, 95% CI: 1.152-4.092), CA19-9≥37 kU/L ( HR=2.401, 95% CI: 1.094-5.269), and T3-T4 stages ( HR=2.779, 95% CI: 1.049-7.358) and N2-N3 stages ( HR=2.072, 95% CI: 1.100-3.904). ROC analysis showed that the sensitivity, specificity, and accuracy of MLF1IP (the cut-off value was 3.00 relative protein expression level) in assessing the 5-year survival rate after radical gastrectomy for gastric cancer was 75.00%, 76.92%, and 76.2%, respectively ( P<0.05). CCK-8, Transwell assay, and scratch assays showed that in vitro knocking down of MLF1 IP gene expression significantly inhibited the proliferation, migration and invasion of gastric cancer cells. Subcutaneous tumor xenograft experiment in nude mice showed that knocking down MLF1 IP gene significantly inhibited tumor growth. Conclusion: Increased expression of MLF1IP in gastric cancer tissue, which may be involved in the malignant activities of proliferation, migration, and invasion of gastric cancer cells, has a certain predictive value for poor prognosis.


Asunto(s)
Leucemia Mieloide , Neoplasias Gástricas , Animales , Ratones , Humanos , Pronóstico , Antígeno Carcinoembrionario , Neoplasias Gástricas/patología , Ratones Desnudos , Estudios Retrospectivos , Antígeno CA-19-9
7.
J Food Sci Technol ; 60(3): 1163-1174, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36908347

RESUMEN

Elm bark (Ulmus pumila L.) flour is a nutritious and sustainable edible material for developing the macromolecular network in the food matrix. In this study, the effects of Elm bark flour and water addition on technological and sensory characteristics of gluten-free whole foxtail millet bread were investigated. Structural analysis methods such as SEM, X-ray diffraction, and FTIR were used to supplement the rheological properties and baking quality. Results showed that Elm bark flour improved gelatinization characteristics and rheological properties (tanδ < 1) of gluten-free dough. Moreover, the porous and network structure of gluten-free bread was observed by image analysis and further confirmed by Fourier transform infrared spectroscopy and X-Ray diffraction, endowing higher specific volume (1.98 ± 0.13 cm3/g), and a decrease hardness from 97.43 to 11.56 N. Additionally, with the incorporation of Elm bark flour-water combination, specific volume (2.15 ± 0.09 cm3/g) and hardness (6.83 ± 0.50 N) were further optimized. Combined with the results of rheological properties and bread structure, Elm bark flour at 15% ratio and water addition at 120% level exhibited the most potent improvement of gluten-free bread. These results might contribute to the potential utilization of Elm bark flour as the sustainable resource in gluten-free products. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05670-x.

8.
Inorg Chem ; 60(9): 6753-6763, 2021 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-33856789

RESUMEN

The solution behavior of a polyoxometalate cluster, LiNa-U24Pp12 (Li24Na24[(UO2O2)24(P2O7)12]) that consists of 24 uranyl ions, peroxide groups, and 12 pyrophosphate linkers, was successfully predicted based on new thermodynamic results using a calorimetric method recently described for uranyl peroxide nanoclusters (UPCs), molybdenum blues, and molybdenum browns. The breakdown of LiNa-U24Pp12 and formation of U24 (Li24[UO2O2OH]24) was monitored in situ via Raman spectroscopy using a custom heating apparatus. A combination of analytical techniques confirmed the simultaneous existence of U24Pp12 and U24 midway through the conversion process and U24 as the single end product. The application of a molecular weight filter resulted in a complete and successful separation of UPCs from solution and, in conjunction with DOSY results, confirmed the presence of large intermediate cluster building blocks.

9.
Int J Immunogenet ; 48(3): 229-238, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33527680

RESUMEN

Genetic polymorphisms of human leucocyte antigen (HLA)-DRB1, -DQA1 and -DQB1 among four main ethnic groups including Han (n = 70), Uyghur (n = 71), Kazakh (n = 52) and Hui (n = 40) subjects from Xinjiang Uyghur Autonomous Region were investigated using a polymerase chain reaction-sequence-based typing (PCR-SBT). In total, 32 HLA-DRB1 alleles, eight HLA-DQA1 alleles and 14 HLA-DQB1 alleles were identified. The most predominant HLA-DRB1, -DQA1 and -DQB1 alleles were DRB1*15:01 (12.50%), DQA1*01:02 (21.43%) and DQB1*03:01 (19.29%) in Han; DRB1*07:01 (18.48%), DQA1*05:01/03/05 (24.65%) and DQB1*02:01/02 (31.69%) in Uyghur; and DRB1*13:01 (13.64%), DQA1*05:01/03/05 (28.85%) and DQB1*02:01/02 (27.88%) in Kazakh, respectively. In Hui, DRB1*07:01, DRB1*11:01 and DRB1*14:01 were the most dominant alleles with the same frequency of 11.8%, while the predominant DQA1 and DQB1 alleles were DQA1*03:01/02/03 (23.75%) and DQB1*02:01/02 (16.25%), respectively. In addition, the most common two-locus haplotypes were DQA1*05:01/03/5-DQB1*03:01 (10.0%) in Han; DQA1*02:01-DQB1*02:01/02 (18.31%) in Uyghur; DQA1*05:01/03/05-DQB1*02:01/02 (15.38%) in Kazakh; and DQA1*03:01/02/03-DQB1*03:03 (11.25%) in Hui. The phylogenetic dendrograms constructed based on the allele frequencies of HLA-DRB1, -DQA1 and -DQB1 in 13 populations (e.g. Asian, Central Asian and European) revealed that the Han and Hui populations were clustered together and closest to Han population from China, while the Kazakh and Uyghur populations were closest to each other and two ethnic groups were clustered together with Central Asian and European populations.


Asunto(s)
Genética de Población , Cadenas alfa de HLA-DQ/genética , Cadenas beta de HLA-DQ/genética , Cadenas HLA-DRB1/genética , Alelos , Pueblo Asiatico/genética , China/epidemiología , Etnicidad/genética , Femenino , Frecuencia de los Genes , Genotipo , Cadenas alfa de HLA-DQ/inmunología , Cadenas beta de HLA-DQ/inmunología , Cadenas HLA-DRB1/inmunología , Haplotipos/genética , Haplotipos/inmunología , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Masculino , Filogenia , Polimorfismo Genético/genética
10.
Inorg Chem ; 59(14): 9881-9888, 2020 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-32644786

RESUMEN

Benzene-1,2-diphosphonic acid (Ppb) was introduced into the uranyl peroxide cluster system, resulting in three Ppb-functionalized uranyl peroxide clusters, (UO2)20(O2)20(C6H4P2O6)1040- (U20Ppb10), (UO2)26(O2)33(C6H4P2O6)638- (U26Ppb6), and (UO2)20(O2)24(C6H4P2O6)632- (U20Ppb6). Dissolution experiments were performed for the potassium salts of U20Ppb10 and U26Ppb6, which revealed the capacity of U20Ppb10 to dissolve in the organic solvent dimethyl sulfoxide (DMSO). Unlike U20Ppb10, the K salt of U26Ppb6 did not dissolve in DMSO but was more soluble in water, perhaps due to the lower proportion of Ppb ligands in its structure. In this work, U20Ppb10 and U20Ppb6 formed as potassium salts and both adopt the fullerene topology of previously reported U20. U20 contains 20 uranyl peroxide units and encapsulates 12 Na cations. It is not possible for unfunctionalized U20 to incorporate 12 K cations owing to space constraints, as is the case in the new clusters reported here. Transformation of U20Ppb10 in water over time to produce U24 was observed, possibly owing to its ability to incorporate K cations, which have been associated with the formation of U24.

11.
Angew Chem Int Ed Engl ; 59(46): 20450-20454, 2020 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-32691946

RESUMEN

The Catellani reaction has received substantial attention because it enables rapid multiple derivatization on aromatics. While using alkyl electrophiles to achieve ortho-alkylation was one of the earliest applications of the Catellani reaction, ipso-alkylation-terminated reactions with ß-H-containing reactants has not been realized to date. Herein, we report alkylation-terminated Catellani reaction using alkyl carbagermatranes (abbreviated as alkyl-Ge) as nucleophiles. The reactivity of alkyl-Ge and alkyl-B(OH)2 in this reaction is discussed. This approach enables efficient dialkylation with ß-H-containing reactants, which was previously inaccessible by Catellani reactions.

12.
J Am Chem Soc ; 141(32): 12780-12788, 2019 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-31339704

RESUMEN

An aromatic ligand was introduced into the synthesis of a uranyl peroxide polyoxometalate formulated as K32(UO2)19(O2)26(OH)2(C6H4P2O6)4·65H2O that consists of a unique "open oyster" shaped structure (U19) with intramolecular H-bonds. In the solid state, K-π and π-π interactions as well as K-O bonds enable the formation of a supramolecular network between U19 clusters. U19 adopts an incomplete fullerene topology and was utilized as a precursor from which the geometrically favored U24 structure was produced. A potassium-encapsulated U24 structure was obtained upon heating the solution containing U19.

13.
J Am Chem Soc ; 141(18): 7582-7588, 2019 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-30998348

RESUMEN

Pd-catalyzed cross-coupling reactions have achieved tremendous accomplishments in the past decades. However, C(sp3)-hybridized nucleophiles generally remain as challenging coupling partners due to their sluggish transmetalation compared to the C(sp2)-hybridized counterparts. While a single-electron-transfer-based strategy using C(sp3)-hybridized nucleophiles had made significant progress recently, fewer breakthroughs have been made concerning the traditional two-electron mechanism involving C(sp3)-hybridized nucleophiles. In this report, we present a series of unique alkyl carbagermatranes that were proven to be highly reactive in cross-coupling reactions with our newly developed electron-deficient phosphine ligands. Generally, secondary alkyl carbagermatranes show slightly lower, yet comparable activity to its Sn analogue. Meanwhile, primary alkyl carbagermatranes exhibit high activity, and they were also proved stable enough to be compatible with various reactions. Chiral secondary benzyl carbagermatrane gave the coupling product under base/additive-free conditions with its configuration fully inversed, suggesting that transmetalation was carried out in an "SE2(open) Inv" pathway, which is consistent with Hiyama's previous observation. Notably, the cross-coupling of primary alkyl carbagermatranes could be performed under base/additive-free conditions with excellent functional group tolerance and therefore may have potentially important applications such as stapled peptide synthesis.

14.
Entropy (Basel) ; 22(1)2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-33285830

RESUMEN

This paper is concerned with the estimation of time-varying networks for high-dimensional nonstationary time series. Two types of dynamic behaviors are considered: structural breaks (i.e., abrupt change points) and smooth changes. To simultaneously handle these two types of time-varying features, a two-step approach is proposed: multiple change point locations are first identified on the basis of comparing the difference between the localized averages on sample covariance matrices, and then graph supports are recovered on the basis of a kernelized time-varying constrained L 1 -minimization for inverse matrix estimation (CLIME) estimator on each segment. We derive the rates of convergence for estimating the change points and precision matrices under mild moment and dependence conditions. In particular, we show that this two-step approach is consistent in estimating the change points and the piecewise smooth precision matrix function, under a certain high-dimensional scaling limit. The method is applied to the analysis of network structure of the S&P 500 index between 2003 and 2008.

15.
Angew Chem Int Ed Engl ; 54(44): 12957-61, 2015 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-26338141

RESUMEN

A novel copper-catalyzed regiodivergent alkylboration of alkenes with bis(pinacolato)diboron and alkyl halides has been developed. The regioselectivity of the alkylboration was controlled by subtle differences in the ligand structure. The reaction thus enables the practical, regiodivergent synthesis of two different alkyl boronic esters with complex structures from a single alkene.


Asunto(s)
Alquenos/química , Compuestos de Boro/síntesis química , Cobre/química , Compuestos Organometálicos/química , Compuestos de Boro/química , Catálisis , Ligandos , Estructura Molecular , Estereoisomerismo
16.
Spectrochim Acta A Mol Biomol Spectrosc ; 314: 124195, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38547782

RESUMEN

The carbon dots (CDs) with excellent optical properties and their hydrogel complex are of great significance in biomedicine, healthcare and biochemical detection fields. This paper reports the preparation of green-emitting CDs (MA-CDs) through one-step hydrothermal route with citric acid as reducing agent, L-malic acid as carbon source and N-(2-hydroxyethyl)ethylenediamine as nitrogen source. To expand its application in biology, MA-CDs were coupled with vancomycin to obtain multifunctional CDs (VMA-CDs). The prepared VMA-CDs exhibit selective antibacterial behavior to Gram-positive bacteria, and it could be used as a fluorescent probe to selectively label Staphylococcus aureus (S. aureus). Moreover, thanks to the excellent optical properties of VMA-CDs, it has been used as a fluorescent sensor to detect Au3+ with detection range of 6.50 nM-21.93 µM and detection limit 3.98 nM. By introducing the fluorescence of CDs as the reference signal, and VMA-CDs as a response signal, the hydrogel (V-SP) was prepared and realized the detection of Au3+ in microfluidics with assistance of a smartphone to collect and analyze data.


Asunto(s)
Hidrogeles , Puntos Cuánticos , Puntos Cuánticos/química , Carbono/química , Staphylococcus aureus , Antibacterianos/farmacología , Colorantes Fluorescentes/química , Nitrógeno/química , Espectrometría de Fluorescencia
17.
Org Lett ; 26(3): 636-641, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38273796

RESUMEN

A photochemical halogen-bonding-assisted synthesis of vinyl sulfones via radical-radical cross-coupling of vinyl bromines and sodium sulfinates is developed. This methodology offers a facile and efficient approach to various vinyl sulfones with excellent functional group tolerance under metal-, photocatalyst-, base-, and oxidant-free conditions. The reaction is also applicable for the late-stage functionalization of drug molecules and the hectogram scale. Moreover, instead of sodium sulfites being prepared, these reactions could also be conducted using sulfonyl chlorides in a one-pot method.

18.
Micromachines (Basel) ; 14(10)2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37893303

RESUMEN

A 1 × 2 low-profile filtering antenna array is proposed, using an H-shape resonator to feed two strip dense dielectric patch (DDP) resonators. The even-odd mode of the H-shape resonator and the TMδ1 mode of the strip DDP resonator form the radiation band. Additionally, the odd-odd mode of the H-shape resonator excites the TMδ2 mode of the strip DDP resonator, thus achieving an upper-edge radiation null for the filtering response. The H-shape resonator not only participates in the antenna array radiation, but also excites two strip media patches at the same time, avoiding the traditional power distribution network and effectively reducing the complexity of the antenna array. In addition, compared with the reported dielectric filtering antenna designs, this design has the advantageous features of a low profile, a compact structure, wide bandwidth and a simplified structure. For example, the antenna prototype operating at 4.9 GHz achieves 10 dB impedance, a matching bandwidth of 7.1%, a maximum gain of 8.6 dBi and the compact size of 1.29 × 0.18 × 0.038 λ03, without requiring a traditional power division network.

19.
Int J Biol Macromol ; 231: 123303, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36657551

RESUMEN

The preparation of functional long-wavelength-emitting nanomaterials and the researches on their applications in antibacterial and antibiofilm fields have important significance. This paper reports the preparation of yellow-green-fluorescent and high- quantum yield carbon dots (4-ACDs) with 4-aminosalicylic acid and polyethylene imine as raw materials through one-step route, and the impacts of raw material structure and the reaction conditions upon the optical properties of the products have been investigated. 4-ACDs exhibit excellent broad-spectrum antibacterial activity, and their good biocompatibility ensures them as ideal fluorescent nano-probe for cell imaging. However, 4-ACDs could not effectively eliminate the biofilm of Staphylococcus aureus (S. aureus). CDs-LZM complex was prepared through the coupling between 4-ACDs and lysozyme (LZM) and the complex showed strong antibacterial activity against Gram-positive bacteria, particularly with MIC against S. aureus at 5 µg mL-1. Besides, CDs-LZM showed excellent ability against the biofilm of S. aureus. At the concentration of 60 µg mL-1, its inhibition rate against the growth of biofilm was 86 %, and elimination rate against biofilm reached 76 %. CDs-LZM exhibited obvious antibiofilm ability through removing extracellular matrix of biofilm, greatly reducing the thickness of biofilm under confocal microscopy. The application of novel long-wavelength-emitting nanomaterial in eliminating pathogenic bacteria is of great significance.


Asunto(s)
Puntos Cuánticos , Infecciones Estafilocócicas , Humanos , Staphylococcus aureus , Carbono/química , Muramidasa/farmacología , Antibacterianos/farmacología , Biopelículas , Bacterias , Puntos Cuánticos/química , Colorantes Fluorescentes/química
20.
Org Lett ; 25(40): 7434-7439, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37768735

RESUMEN

Herein, a facile and efficient dehalogenative arylation of unactivated alkyl halides enabled by electrochemical reductive coupling is developed, affording a series of C(sp2)-C(sp3) products in moderate to good yields. This protocol proceeds in the absence of transition metal catalysts and redox mediators. The reaction features mild conditions, broad substrate scope, and high tolerance of functional groups and is demonstrated to be applicable for gram-scale synthesis and late-stage functionalization of natural products.

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