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1.
Angew Chem Int Ed Engl ; : e202403963, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635317

RESUMO

(±)-Penindolenes A-D (1-4), the first representatives of indole terpenoids featuring a γ-lactam skeleton, were isolated from the mangrove-derived endophytic fungus Penicillium brocae MA-231. Our bioactivity tests revealed their potent antimicrobial and acetylcholinesterase inhibitory activities. The biosynthetic reactions by the five enzymes PbaABCDE leading to γ-lactam ring formation were identified with heterologous expression and in vitro enzymatic assays. Remarkably, the cytochrome P450 monooxygenase PbaB and its homolog in Aspergillus oryzae  catalyzed the 2,3-cleavage of the indole ring to generate two keto groups in 1, in different manners from well-known tryptophan dioxygenases. This is the first example of the oxidative cleavage of indole by a P450 monooxygenase. In addition, rare secondary amide bond formation by the glutamine synthetase-like enzyme PbaD was reported. These findings will contribute to the engineered biosynthesis of unnatural, bioactive indole terpenoids.

2.
Chem Biodivers ; : e202400584, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38544421

RESUMO

Two pairs of new enantiomeric hydroxyphenylacetic acid derivatives, (±)-corylophenols A and B ((±)-1 and (±)-2), a new α-pyrone analogue, corylopyrone A (3), and six andrastin-type meroterpenoids (4-9) were isolated and identified from the deep-sea cold-seep sediment-derived fungus Penicillium corylophilum CS-682. Their structures and stereo configurations were determined by detailed spectroscopic analysis of NMR and MS data, chiral HPLC analysis, J-based configuration analysis, and quantum chemical calculations of ECD, specific rotation, and NMR (with DP4+ probability analysis). Compound 3 showed inhibitory activity against some strains of pathogenic bacteria.

3.
Beilstein J Org Chem ; 20: 470-478, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38440169

RESUMO

Pseudallenes A and B (1 and 2), the new and rare examples of sulfur-containing ovalicin derivatives, along with three known analogues 3-5, were isolated and identified from the culture extract of Pseudallescheria boydii CS-793, a fungus obtained from the deep-sea cold seep sediments. Their structures were established by detailed interpretation of NMR spectroscopic and mass spectrometric data. X-ray crystallographic analysis confirmed and established the structures and absolute configurations of compounds 1-3, thus providing the first characterized crystal structure of an ovalicin-type sesquiterpenoid. In the antimicrobial assays, compounds 1-3 showed broad-spectrum inhibitory activities against several plant pathogens with MIC values ranging from 2 to 16 µg/mL.

4.
Environ Microbiol ; 26(2): e16567, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38233213

RESUMO

Soluble di-iron monooxygenase (SDIMO) enzymes enable insertion of oxygen into diverse substrates and play significant roles in biogeochemistry, bioremediation and biocatalysis. An unusual SDIMO was detected in an earlier study in the genome of the soil organism Solimonas soli, but was not characterized. Here, we show that the S. soli SDIMO is part of a new clade, which we define as 'Group 7'; these share a conserved gene organization with alkene monooxygenases but have only low amino acid identity. The S. soli genes (named zmoABCD) could be functionally expressed in Pseudomonas putida KT2440 but not in Escherichia coli TOP10. The recombinants made epoxides from C2 C8 alkenes, preferring small linear alkenes (e.g. propene), but also epoxidating branched, carboxylated and chlorinated substrates. Enzymatic epoxidation of acrylic acid was observed for the first time. ZmoABCD oxidised the organochlorine pollutants vinyl chloride (VC) and cis-1,2-dichloroethene (cDCE), with the release of inorganic chloride from VC but not cDCE. The original host bacterium S. soli could not grow on any alkenes tested but grew well on phenol and n-octane. Further work is needed to link ZmoABCD and the other Group 7 SDIMOs to specific physiological and ecological roles.


Assuntos
Gammaproteobacteria , Pseudomonas putida , Cloreto de Vinil , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Alcenos/metabolismo , Gammaproteobacteria/metabolismo , Biodegradação Ambiental , Pseudomonas putida/genética , Pseudomonas putida/metabolismo
5.
Bioorg Chem ; 143: 107073, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176375

RESUMO

Six new highly oxygenated and polycyclic andrastin-type meroterpenoids, namely, bialorastins A-F (1-6), were discovered from the culture of Penicillium bialowiezense CS-283, a fungus isolated from the deep-sea cold seep squat lobster Shinkaia crosnieri. The planar structures and absolute configurations of these compounds were determined by detailed analysis of spectroscopic data, single crystal X-ray diffraction, and TDDFT-ECD calculations. Structurally, bialorastin A (1) represents a rare 17-nor-andrastin that possesses an unusual 2-oxaspiro[4.5]decane-1,4-dione moiety with a unique 6/6/6/6/5 polycyclic system, while bialorastin B (2) is also a 17-nor-andrastin featuring a gem-propane-1,2-dione moiety. Additionally, bialorastins C-E (3-5) possess a 6/6/6/6/5/5 fused hexacyclic skeleton, characterized by distinctive 3,23-acetal/lactone-bridged functionalities. All isolated compounds were evaluated for their proangiogenic activities in transgenic zebrafish. Compound 3 exhibited significant proangiogenic activity, which notably increased the number and length of intersegmental blood vessels in model zebrafish in a dose-dependent manner at concentrations of 20 and 40 µM. On a molecular scale, the tested compounds were modeled through molecular docking to have insight into the interactions with the possible target VEGFR2. Mechanistically, RT-qPCR results revealed that compound 3 could promote angiogenesis via activating VEGFR2 and subsequently activating the downstream PI3K/AKT and MAPK signaling pathways. These findings indicate that 3 could be a potential lead compound for developing angiogenesis agents.


Assuntos
Penicillium , Terpenos , Peixe-Zebra , Animais , Fungos , Simulação de Acoplamento Molecular , Estrutura Molecular , Penicillium/química , Fosfatidilinositol 3-Quinases , Terpenos/química , Terpenos/farmacologia
6.
Small ; 20(6): e2306394, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37775949

RESUMO

Nanoparticles form long-range micropatterns via self-assembly or directed self-assembly with superior mechanical, electrical, optical, magnetic, chemical, and other functional properties for broad applications, such as structural supports, thermal exchangers, optoelectronics, microelectronics, and robotics. The precisely defined particle assembly at the nanoscale with simultaneously scalable patterning at the microscale is indispensable for enabling functionality and improving the performance of devices. This article provides a comprehensive review of nanoparticle assembly formed primarily via the balance of forces at the nanoscale (e.g., van der Waals, colloidal, capillary, convection, and chemical forces) and nanoparticle-template interactions (e.g., physical confinement, chemical functionalization, additive layer-upon-layer). The review commences with a general overview of nanoparticle self-assembly, with the state-of-the-art literature review and motivation. It subsequently reviews the recent progress in nanoparticle assembly without the presence of surface templates. Manufacturing techniques for surface template fabrication and their influence on nanoparticle assembly efficiency and effectiveness are then explored. The primary focus is the spatial organization and orientational preference of nanoparticles on non-templated and pre-templated surfaces in a controlled manner. Moreover, the article discusses broad applications of micropatterned surfaces, encompassing various fields. Finally, the review concludes with a summary of manufacturing methods, their limitations, and future trends in nanoparticle assembly.

7.
J Antibiot (Tokyo) ; 76(12): 699-705, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37848580

RESUMO

Two new nonadride derivatives, namely, talarodrides G and H (1 and 2), and one new depsidone derivative, botryorhodine K (3), together with a known nonadride analogue (4), were characterized from the Magellan Seamount-derived fungus Talaromyces scorteus AS-242. Their structures were established by detailed interpretation of NMR spectroscopic and mass spectrometry data analysis. X-ray crystallographic analysis of compounds 1 and 3 confirmed their structures and absolute configurations, representing the first characterized crystal structure of a nonadride-type polyketide. The isolated compounds exhibited potent antimicrobial activities against the pathogenic bacterium MRSA and V. parahaemolyticus and pathogenic fungi C. gloeosporioides, F. oxysporum, and F. proliferatum, with MIC values ranging from 1 to 64 µg ml-1.


Assuntos
Anti-Infecciosos , Policetídeos , Talaromyces , Policetídeos/química , Anti-Infecciosos/química , Talaromyces/química , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular
8.
Opt Express ; 31(17): 27324-27331, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710811

RESUMO

The control of resonant metasurface for electromagnetically induced transparency (EIT) offers unprecedented opportunities to tailor lightwave coupling at the nanoscale leading to many important applications including slow light devices, optical filters, chemical and biosensors. However, the realization of EIT relies on the high degree of structural asymmetry by positional displacement of optically resonant structures, which usually lead to low quality factor (Q-factor) responses due to the light leakage from structural discontinuity from asymmetric displacements. In this work, we demonstrate a new pathway to create high quality EIT metasurface without any displacement of constituent resonator elements. The mechanism is based on the detuning of the resonator modes which generate dark-bright mode interference by simply introducing a slot in metasurface unit cells (meta-atoms). More importantly, the slot diameter and position on the meta-atom can be modulated to tune the transmittance and quality factor (Q-factor) of the metasurface, leading to a Q-factor of 1190 and near unity transmission at the same time. Our work provides a new degree of freedom in designing optically resonant elements for metamaterials and metasurfaces with tailored wave propagation and properties.

9.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(8): 791-799, 2023 Aug 15.
Artigo em Chinês | MEDLINE | ID: mdl-37668025

RESUMO

OBJECTIVES: To investigate the association of single nucleotide polymorphisms (SNPs) of myeloid differentiation factor 88 (MyD88) and Toll-like receptor adaptor molecule 1 (TICAM1) and their interactions with community-acquired pneumonia (CAP) in children. METHODS: Improved multiple ligase detection reaction assay was used for detecting the polymorphisms of nine tagging SNPs of the MyD88 and TICAM1 genes in 375 children with CAP who attended the Department of Pediatrics of the Second Affiliated Hospital of Yan'an University Medical School from August 2015 to September 2017 and 306 healthy children who underwent physical examination. A logistic regression analysis was used to evaluate the association between the distribution of genotypes and their interactions with CAP in children. RESULTS: The polymorphism of the TICAM1 gene at rs11466711T/C locus was closely associated with the susceptibility to CAP in children (P<0.05). The AA genotype of rs35747610G/A locus significantly reduced risk of sepsis in children with CAP (P<0.05). The AA genotype of rs6510826G/A locus was significantly associated with the increase in C-reactive protein level in children with CAP (P<0.05). The GG genotype of the MyD88 gene at rs7744A/G locus significantly increased the risk of respiratory failure and circulatory failure (P<0.05). The multiplicative interactions between MyD88 gene rs7744A/G and TICAM1 gene rs11466711T/C, rs2292151G/A, rs35299700C/T, and rs35747610G/A loci were significantly associated with the susceptibility to CAP, the severity of CAP, and the risk of sepsis in children (P<0.05). CONCLUSIONS: The gene polymorphisms of MyD88 and TICAM1 and their interactions are closely associated with CAP in children, with a synergistic effect on the development and progression of CAP in children.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular , Infecções Comunitárias Adquiridas , Fator 88 de Diferenciação Mieloide , Pneumonia , Criança , Humanos , Proteínas Adaptadoras de Transporte Vesicular/genética , Infecções Comunitárias Adquiridas/genética , Fator 88 de Diferenciação Mieloide/genética , Pneumonia/genética , Polimorfismo de Nucleotídeo Único , Sepse
10.
Mar Life Sci Technol ; 5(2): 223-231, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37275535

RESUMO

Verrucosidins, a methylated α-pyrone class of polyketides rarely reported upon, have been implicated in one or more neurological diseases. Despite the significance of verrucosidins as neurotoxins, the absolute configurations of most of the derivatives have not been accurately characterized yet. In this study, three pairs of C-9 epimeric verrucosidin derivatives, including the known compounds penicyrones A and B (1a/1b) and 9-O-methylpenicyrones A and B (2a/2b), the new compounds 9-O-ethylpenicyrones A and B (3a/3b), together with the related known derivative verrucosidin (4), were isolated and identified from the culture extract of Penicillium cyclopium SD-413, which was obtained from the marine sediment collected from the East China sea. Their structures were established based on an in-depth analysis of nuclear magnetic resonances (NMR) and mass spectroscopic data. Determination of the absolute configurations of these compounds was accomplished by Mosher's method and time-dependent density functional theory (TDDFT) calculations of electronic circular dichroism (ECD) and optical rotation (OR). The configurational assignment of penicyrone A demonstrated that the previously reported C-6 absolute configuration of verrucosidin derivatives needs to be revised from (6S) to (6R). The 9R/9S epimers of compounds 1-3 were found to exhibit growth inhibition against some pathogenic bacteria, indicating that they have potential as lead compounds for the creation of antimicrobial agents. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-023-00173-2.

11.
Nat Prod Res ; : 1-6, 2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-37086479

RESUMO

Three new α-pyrone derivatives, annularins L-N (1-3), were isolated from the EtOAc extract of Penicillium herquei MA-370, a fungus obtained from the rhizospheric soil of the mangrove plant Rhizophora mucronata. The planar structures of compounds 1-3 were determined based on comprehensive spectral interpretation of the NMR and MS data. The absolute configuration of 1 was determined by X-ray crystallographic data and that of 2 was assigned by TDDFT calculations of its ECD spectrum and cotton effects comparison with those of 1. The antimicrobial activity of compounds 1-3 was evaluated.

12.
Sci Total Environ ; 876: 162798, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-36914136

RESUMO

Electrochemical process coupling with ultraviolet light-emitting diode for micropollutant abatement was evaluated in the treatment of wastewater containing Cl-. Four representative micropollutants, atrazine, primidone, ibuprofen and carbamazepine, were selected as target compounds. The impacts of operating conditions and water matrix on micropollutant degradation were investigated. Fluorescence excitation-emission matrix spectroscopy spectra and high performance size exclusion chromatography were employed to characterize the transformation of effluent organic matter in treatment. The degradation efficiencies of atrazine, primidone, ibuprofen and carbamazepine are 83.6 %, 80.6 %, 68.7 % and 99.8 % after 15 min treatment, respectively. The increment of current, Cl- concentration and ultraviolet irradiance promote the micropollutant degradation. However, the presence of bicarbonate and humic acid inhibit micropollutant degradation. The mechanism of micropollutant abatement was elaborated based on reactive species contributions, density functional theory calculation and degradation routes. Free radicals (HO•, Cl•, ClO• and Cl2•-) could be generated by chlorine photolysis and subsequent propagation reactions. The concentrations of HO• and Cl• are 1.14 × 10-13 M and 2.0 × 10-14 M in optimal condition, respectively, and the total contributions of HO• and Cl• for the degradation of atrazine, primidone, ibuprofen and carbamazepine are 24 %, 48 %, 70 % and 43 %, respectively. The degradation routes of four micropollutants are elucidated based on intermediate identification, Fukui function and frontier orbital theory. Micropollutants can be effectively degraded in actual wastewater effluent, and the small molecule compound proportion increases during effluent organic matter evolution. Compared with photolysis and electrolysis, the coupling of the two processes has potential for energy saving in micropollutant degradation, which shed light on the prospects of ultraviolet light-emitting diode coupling with electrochemical process for effluent treatment.

13.
Mar Drugs ; 21(3)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36976244

RESUMO

A large body of fungal secondary metabolites has been discovered to exhibit potent antibacterial activities with distinctive mechanisms and has the potential to be an untapped resource for drug discovery. Here, we describe the isolation and characterization of five new antibacterial indole diketopiperazine alkaloids, namely 24,25-dihydroxyvariecolorin G (1), 25-hydroxyrubrumazine B (2), 22-chloro-25-hydroxyrubrumazine B (3), 25-hydroxyvariecolorin F (4), and 27-epi-aspechinulin D (5), along with the known analogue neoechinulin B (6) from a fungal strain of deep-sea cold seep-derived Aspergillus chevalieri. Among these compounds, 3 and 4 represented a class of infrequently occurring fungal chlorinated natural products. Compounds 1-6 showed inhibitory activities against several pathogenic bacteria with MIC values ranging from 4 to 32 µg/mL. It was revealed that compound 6 could induce structural damage to the Aeromonas hydrophila cells based on the observation by scanning electron microscopy (SEM), which led to the bacteriolysis and death of A. hydrophila, suggesting that neoechinulin B (6) might be a potential alternative to novel antibiotics development.


Assuntos
Alcaloides , Dicetopiperazinas , Dicetopiperazinas/química , Estrutura Molecular , Antibacterianos/química , Alcaloides Indólicos/química , Alcaloides/química , Fungos/química
14.
Chem Biodivers ; 20(4): e202300229, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36866699

RESUMO

Rubenpolyketone A (1), a polyketide featuring a new carbon skeleton having cyclohexenone condensed with a methyl octenone chain and a new linear sesquiterpenoid, chermesiterpenoid D (2), together with seven known secondary metabolites (3-9) were isolated and identified from the Magellan Seamount-derived fungus Penicillium rubens AS-130. Their structures were determined based on detailed analysis of NMR and mass spectroscopic data and the absolute configurations of these two new compounds were elucidated by the combination of quantum mechanical (QM)-NMR and time-dependent density functional (TDDFT) ECD calculation approaches. Chermesiterpenoids B (3) and C (4) showed potent inhibitory activities against the aquatic pathogen Vibrio anguillarum with MIC values of 0.5 and 1 µg/mL, respectively, while chermesin F (6) exhibited activity against Escherichia coli with MIC value of 1 µg/mL.


Assuntos
Penicillium , Policetídeos , Sesquiterpenos , Estrutura Molecular , Policetídeos/química , Sesquiterpenos/química , Penicillium/química
15.
Org Biomol Chem ; 21(12): 2575-2585, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36880760

RESUMO

Seven new highly oxygenated natural products with diverse chemical structural types, including three new glucosidic polyketides, talaminiosides A-C (1-3), a pair of racemic aromatic polyketides, (±)-talaminone A (4a and 4b), two new azaphilone polyketides, (+)-5-chloromitorubrinic acid (5) and 7-epi-purpurquinone C (7), and one new drimane sesquiterpene lactone, 11-hydroxyminioluteumide B (8), together with a pinazaphilone B sodium salt (6) and 10 known compounds (9-18), were isolated and identified from the culture extract of Talaromyces minioluteus CS-113, a fungus obtained from deep-sea cold-seep sediments collected from the South China Sea. LCMS results indicated that compounds 3 and 4 might be produced by the real activation of silent BGCs triggered by the histone deacetylase inhibitor SAHA, and some of the other compounds were enhanced minor components. Their structures were elucidated by the detailed interpretation of NMR spectroscopic and mass spectrometric data, X-ray crystallographic analysis, ECD and specific rotation (SR) calculations, and DP4+ probability analysis. Compound 7, an azaphilone derivative, exhibited potent activities against several agricultural pathogenic fungi with MIC values equivalent or comparable to amphotericin B. The structure-activity relationship of the isolated azaphilones is briefly discussed. This is the first report of the chemical diversity study of deep-sea cold-seep-derived fungi triggered by SAHA, providing a useful strategy for the activation of cryptic fungal metabolites from deep-sea-derived fungi.


Assuntos
Anti-Infecciosos , Policetídeos , Talaromyces , Policetídeos/química , Inibidores de Histona Desacetilases , Espectroscopia de Ressonância Magnética , Estrutura Molecular
16.
Phys Rev Lett ; 130(3): 036902, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36763375

RESUMO

The newly discovered valley degree of freedom in atomically thin two-dimensional transition metal dichalcogenides offers a promising platform to explore rich nonlinear physics, such as spinor Bose-Einstein condensate and novel valleytronics applications. However, the critical nonlinear effect, such as valley polariton bosonic stimulation, has long remained an unresolved challenge due to the generation of limited polariton ground state densities necessary to induce the stimulated scattering of polaritons in specific valleys. Here, we report the self-induced valley bosonic stimulation of exciton polaritons via spin-valley locking in a WS_{2} monolayer microcavity. This is achieved by the resonant injection of valley polaritons at specific energy and wave vector, which allows spin-polarized polaritons to efficiently populate their ground state and induce a valley-dependent bosonic stimulation. As a result, we observe the nonlinear self-amplification of polariton emission from the valley-dependent ground state. Our finding paves the way for the investigation of spin ordering and phase transitions in transition metal dichalcogenides polariton Bose-Einstein condensate, offering a promising route for the realization of polariton spin lattices in moiré polariton systems and spin lasers.

17.
Environ Sci Technol ; 57(47): 18575-18585, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36642924

RESUMO

A novel approach to the abatement of pollutants consisting of their conversion to separable solid polymers is explored by a heat/persulfate (PDS) process for the treatment of high-temperature wastewaters. During this process, a simultaneous decontamination and carbon recovery can be achieved with minimal use of PDS, which is significantly different from conventional degradation processes. The feasibility of this process is demonstrated by eight kinds of typical organic pollutants and by a real coking wastewater. For the treatment of the selected pollutants, 30.2-91.9% DOC abatement was achieved with 24.8-91.2% carbon recovery; meanwhile, only 5.2-47.0% of PDS was consumed compared to a conventional degradation process. For the treatment of a real coking wastewater, 71.0% DOC abatement was achieved with 66.0% carbon recovery. With phenol as a representative compound, our polymerization-based heat/PDS process is applicable in a wide pH range (3.5-9.0) with a carbon recovery of >87%. Both SO4•- and HO• can be initiators for polymerization, with different contribution ratios under various conditions. Phenol monomers are semioxidized to form phenolic radicals, which are polymerized via chain transfer or chain growth processes to form separable solid phenol polymers, benzenediol polymers, and cross-linked polymers.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Temperatura Alta , Polimerização , Poluentes Químicos da Água/análise , Oxirredução , Carbono , Fenol/química , Polímeros
18.
Adv Sci (Weinh) ; 10(5): e2203742, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36541716

RESUMO

Photodynamic therapy (PDT) under hypoxic conditions and drug resistance in chemotherapy are perplexing problems in anti-tumor treatment. In addition, central nervous system neoplasm-targeted nanoplatforms are urgently required. To address these issues, a new multi-functional protein hybrid nanoplatform is designed, consisting of transferrin (TFR) as the multicategory solid tumor recognizer and hemoglobin for oxygen supply (ODP-TH). This protein hybrid framework encapsulates the photosensitizer protoporphyrin IX (PpIX) and chemotherapeutic agent doxorubicin (Dox), which are attached by a glutathione-responsive disulfide bond. Mechanistically, ODP-TH crosses the blood-brain barrier (BBB) and specifically aggregated in hypoxic tumors via protein homology recognition. Oxygen and encapsulated drugs ultimately promote a therapeutic effect by down-regulating the abundance of multidrug resistance gene 1 (MDR1) and hypoxia-inducible factor-1-α (HIF-1α). The results reveal that ODP-TH achieves oxygen transport and protein homology recognition in the hypoxic tumor occupation. Indeed, compared with traditional photodynamic chemotherapy, ODP-TH achieves a more efficient tumor-inhibiting effect. This study not only overcomes the hypoxia-related inhibition in combination therapy by targeted oxygen transport but also achieves an effective treatment of multiple tumors, such as breast cancer and glioma, providing a new concept for the construction of a promising multi-functional targeted and intensive anti-tumor nanoplatform.


Assuntos
Carcinoma , Fotoquimioterapia , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/terapia , Carcinoma/tratamento farmacológico , Carcinoma/terapia , Hipóxia , Oxigênio/farmacologia , Oxigênio/uso terapêutico , Fármacos Fotossensibilizantes/química , Fotoquimioterapia/instrumentação , Fotoquimioterapia/métodos , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Nanomedicina/instrumentação , Nanomedicina/métodos
19.
J Hazard Mater ; 446: 130658, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36580777

RESUMO

Ubiquitous chloride ion (Cl-) in wastewaters usually inhibits the degradation of organic contaminants and generates numerous toxic chlorinated products in conventional degradation-based advanced oxidation processes (AOPs). Herein, a more Cl- tolerant polymerization-based electrochemical AOP for organic contaminants abatement and simultaneous organic resource recovery was demonstrated with eight typical organic contaminants and two real industrial wastewaters for the first time. This process can significantly promote dissolved organic carbon (DOC) abatement in the presence of Cl-, differing greatly from conventional degradation-based processes. Compared to sulfate radical (SO4•-) (or hydroxyl radical (HO•)), dichloride radical (Cl2•-) derived from Cl- has moderate reactivity towards most contaminants, which facilitates the organics polymerization as it ensures the formation of polymerizable organic radicals while inhibiting their excessive degradation. Thus, high DOC abatement (over 75 %) and high organic resource recovery ratio (48-79 % separable organic-polymer yield) can be achieved for most contaminants. Both soluble chlorinated compounds and solid chlorinated polymers are formed in the presence of Cl-. The chlorinated products (e.g. chlorophenols) can be polymerized as new monomers, thus the concentration of dissolved organic chlorinated products is much lower than that in conventional degradation-based process. The tolerance of the present process to Cl- is tested in real coking wastewaters, and exceeding 60 % of the abated chemical oxygen demand (COD) is obtained in the form of recoverable organic-polymers.

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