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1.
Anal Chem ; 96(26): 10714-10723, 2024 07 02.
Artículo en Inglés | MEDLINE | ID: mdl-38913030

RESUMEN

Excessive intake of estrogen poses significant health risks to the human body; hence, there is a necessity to develop rapid detection methods to monitor its levels of addition. Gold nanoparticles (AuNPs), commonly utilized as colorimetric signal labels, find extensive application in lateral flow immunoassay (LFIA). However, the detection sensitivity of traditional AuNPs-LFIA is typically constrained by low molar extinction coefficients and reliance on a single signal. Herein, in this work, unique spark-type AuCuPt nanoflowers modified with tannic acid (AuCuPt@TA) were precisely designed by reasonable layer-by-layer element composition and green modification. The obtained AuCuPt displays robust broadband absorption spanning the visible to near-infrared spectrum, showcasing a notable molar extinction coefficient of 2.38 × 1012 M-1 cm-1 and a photothermal conversion efficiency of 48.5%. Based on this, selecting estriol (E3) as a model analyte, colorimetric/photothermal dual-signal LFIA (CLFIA and PLFIA) was developed. Limits of detection (LOD) of the CLFIA and PLFIA were achieved at 0.033 ng mL-1 and 0.021 ng mL-1, respectively, which represent a 9.3- and 14.6-fold improvement compared to the visual LOD of AuNPs-LFIA. Moreover, the application feasibility of the immunoassay was further evaluated in the milk and pork with satisfactory recoveries ranging from 86.21% to 117.91%. Thus, this work has enhanced the performance of LFIA for E3 detection and exhibited enormous potential for other sensing platform construction.


Asunto(s)
Aleaciones , Estriol , Oro , Nanopartículas del Metal , Inmunoensayo/métodos , Nanopartículas del Metal/química , Oro/química , Estriol/análisis , Aleaciones/química , Animales , Colorimetría , Límite de Detección , Taninos/química , Taninos/análisis
2.
Bioorg Chem ; 93: 103315, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31605927

RESUMEN

Glutamic-oxaloacetic transaminase 1 (GOT1) regulates cellular metabolism through coordinating the utilization of carbohydrates and amino acids to meet nutrient requirements for sustained proliferation. As such, the GOT1 inhibitor may provide a new strategy for the treatment of various cancers. Adapalene has been approved by FDA for the treatment of acne, pimples and pustules, and it may also contribute to the adjunctive therapy for advanced stages of liver and colorectal cancers. In this work, we first examined the enzyme inhibition of over 500 compounds against GOT1 in vitro. As a result, Adapalene effectively inhibited GOT1 enzyme in a non-competitive manner. MST and DARTS assay further confirmed the high affinity between Adapalene and GOT1. Furthermore, the growth and migration of ovarian cancer ES-2 cells were obviously inhibited by the treatment of Adapalene. And it induced the apoptosis of ES-2 cells according to Western blot and Hoechst 33258 straining. In addition, molecular docking demonstrated that Adapalene coordinated in an allosteric site of GOT1 with low binding energy. Furthermore, knockdown of GOT1 in ES-2 cells decreased their anti-proliferative sensitivity to Adapalene. Together, our data strongly suggest Adapalene, as a GOT1 inhibitor, could be regarded as a potential drug candidate for ovarian cancer therapy.


Asunto(s)
Adapaleno/química , Aspartato Aminotransferasa Citoplasmática/antagonistas & inhibidores , Adapaleno/metabolismo , Adapaleno/farmacología , Sitio Alostérico , Aspartato Aminotransferasa Citoplasmática/genética , Aspartato Aminotransferasa Citoplasmática/metabolismo , Sitios de Unión , Dominio Catalítico , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Cinética , Simulación del Acoplamiento Molecular , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/patología , Unión Proteica , Interferencia de ARN , ARN Interferente Pequeño/metabolismo
3.
BMC Plant Biol ; 14: 9, 2014 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-24397545

RESUMEN

BACKGROUND: CO and FT orthologs, belonging to the BBX and PEBP family, respectively, have important and conserved roles in the photoperiod regulation of flowering time in plants. Soybean genome experienced at least three rounds of whole genome duplications (WGDs), which resulted in multiple copies of about 75% of genes. Subsequent subfunctionalization is the main fate for paralogous gene pairs during the evolutionary process. RESULTS: The phylogenic relationships revealed that CO orthologs were widespread in the plant kingdom while FT orthologs were present only in angiosperms. Twenty-eight CO homologous genes and twenty-four FT homologous genes were gained in the soybean genome. Based on the collinear relationship, the soybean ancestral CO ortholog experienced three WGD events, but only two paralogous gene pairs (GmCOL1/2 and GmCOL5/13) survived in the modern soybean. The paralogous gene pairs, GmCOL1/2 or GmCOL5/13, showed similar expression patterns in pair but different between pairs, indicating that they functionally diverged. GmFTL1 to 7 were derived from the same ancestor prior to the whole genome triplication (WGT) event, and after the Legume WGD event the ancestor diverged into two branches, GmFTL3/5/7 and GmFTL1/2/4/6. GmFTL7 were truncated in the N-terminus compared to other FT-lineage genes, but ubiquitously expressed. Expressions of GmFTL1 to 6 were higher in leaves at the flowering stage than that at the seedling stage. GmFTL3 was expressed at the highest level in all tissues except roots at the seedling stage, and its circadian pattern was different from the other five ones. The transcript of GmFTL6 was highly accumulated in seedling roots. The circadian rhythms of GmCOL5/13 and GmFT1/2/4/5/6 were synchronized in a day, demonstrating the complicate relationship of CO-FT regulons in soybean leaves. Over-expression of GmCOL2 did not rescue the flowering phenotype of the Arabidopsis co mutant. However, ectopic expression of GmCOL5 did rescue the co mutant phenotype. All GmFTL1 to 6 showed flower-promoting activities in Arabidopsis. CONCLUSIONS: After three recent rounds of whole genome duplications in the soybean, the paralogous genes of CO-FT regulons showed subfunctionalization through expression divergence. Then, only GmCOL5/13 kept flowering-promoting activities, while GmFTL1 to 6 contributed to flowering control. Additionally, GmCOL5/13 and GmFT1/2/3/4/5/6 showed similar circadian expression profiles. Therefore, our results suggested that GmCOL5/13 and GmFT1/2/3/4/5/6 formed the complicate CO-FT regulons in the photoperiod regulation of flowering time in soybean.


Asunto(s)
Flores/metabolismo , Glycine max/metabolismo , Ritmo Circadiano/fisiología , Flores/genética , Duplicación de Gen/genética , Duplicación de Gen/fisiología , Fotoperiodo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Glycine max/genética
4.
J Nat Prod ; 77(10): 2161-9, 2014 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-25275213

RESUMEN

Eleven new sesquiterpenoids, wenyujinins A-K (1-11), and a new monoterpenoid, wenyujinin L (12), were isolated from the rhizomes of Curcuma wenyujin. Their structures and relative configurations were elucidated using 1D and 2D NMR, X-ray crystallographic analysis, and HRESIMS data. The absolute configurations of 1, 2, 3, 4, 6, 8, 9, and 10 were determined by comparison of the experimental and calculated ECD spectra. The absolute configuration of 5 was determined from the ECD data of the [Rh2(OCOCF3)4] complex, whereas those of 7 and 12 were determined from the ECD spectra of the compounds alone. Compounds 7 and 7a strongly inhibited the induction of NO production by LPS, with IC50 values of 7.6 and 8.5 µM, respectively. Compounds 6 and 10 moderately inhibited NO production with IC50 values of 47.7 and 48.6 µM, respectively.


Asunto(s)
Curcuma/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Monoterpenos/aislamiento & purificación , Monoterpenos/farmacología , Óxido Nítrico Sintasa de Tipo II/antagonistas & inhibidores , Rizoma/química , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Animales , Cristalografía por Rayos X , Medicamentos Herbarios Chinos/química , Concentración 50 Inhibidora , Lipopolisacáridos/farmacología , Macrófagos Peritoneales/efectos de los fármacos , Ratones , Estructura Molecular , Monoterpenos/química , Óxido Nítrico/biosíntesis , Resonancia Magnética Nuclear Biomolecular , Sesquiterpenos/química
5.
Small Methods ; : e2301804, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38859633

RESUMEN

In this study, unique BiVO4-Au-Cu2O nanosheets (NSs) are well designed and multiple charge transfer paths are consequently constructed. The X-ray photoelectron spectroscopy measurement during a light off-on-off cycle and redox capability tests of the photo-generated charge carriers confirmed the formation of Z-scheme heterojunction, which can facilitate the charge carrier separation and transfer and maintain the original strong redox potentials of the respective component in the heterojunction. The ultrathin 2D structure of the BiVO4 NSs provided sufficient surface area for the photocatalytic reaction. The local surface plasmon resonance (LSPR) effect of the electron mediator, Au NPs, enhanced the light absorption and promoted the excitation of hot electrons. The multiple charge transfer paths effectively promoted the separation and transfer of the charge carrier. The synergism of the abovementioned properties endowed the BiVO4-Au-Cu2O NSs with satisfactory photocatalytic activity in the degradation of tetracycline (Tc) with a removal rate of ≈80% within 30 min under visible light irradiation. The degradation products during the photocatalysis are confirmed by using ultra-high performance liquid chromatography-mass spectrometry and the plausible degradation pathways of Tc are consequently proposed. This work paves a strategy for developing highly efficient visible-light-driven photocatalysts with multiple charge transfer paths for removing organic contaminants in water.

6.
J Hazard Mater ; 469: 133979, 2024 05 05.
Artículo en Inglés | MEDLINE | ID: mdl-38492396

RESUMEN

Riverine mercury (Hg) is mainly transported to coastal areas in suspended particulate matter (SPM)-bound form, posing a potential threat to human health. Water discharge and SPM characteristics in rivers vary naturally with seasonality and can also be arbitrarily disrupted by anthropogenic regulation events, but their effects on Hg transport remain unresolved. Aiming to understand the confounding effects of seasonality and anthropogenic river regulation on Hg and SPM transport, this study selected the highly sediment-laden Yellow River as a representative conduit. Significant variations in SPM concentrations (108 - 7097 mg/L) resulted in fluctuations in total mercury (THg, 3.79 - 111 ng/L) in river water corresponding to seasonality and anthropogenic water/sediment regulation. Principal component analysis and structural equation model revealed that SPM was the essential factor controlling THg and particulate Hg (PHg) in river water. While SPM exhibited equilibrium state in the dry season, a net resuspension during the anthropogenic regulation and net deposition in the wet season demonstrated the impact of SPM dynamics on Hg distribution and transport to coastal regions. Combining water discharge, SPM, and Hg concentrations, a modified model was developed to quantify Hg flux (2256 kg), over 98% of which was in particulate phase.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Humanos , Ríos/química , Material Particulado/análisis , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Mercurio/análisis , Agua/análisis , Polvo/análisis , Océanos y Mares , Sedimentos Geológicos/análisis
7.
J Hazard Mater ; 470: 134187, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38574659

RESUMEN

The increasing use of phthalate acid esters (PAEs) in various applications has inevitably led to their widespread presence in the aquatic environment. This presents a considerable threat to plants. However, the interactions between PAEs and plants in the aquatic environment have not yet been comprehensively reviewed. In this review, the properties, occurrence, uptake, transformation, and toxic effects of PAEs on plants in the aquatic environment are summarized. PAEs have been prevalently detected in the aquatic environment, including surface water, groundwater, seawater, and sediment, with concentrations ranging from the ng/L or ng/kg to the mg/L or mg/kg range. PAEs in the aquatic environment can be uptake, translocated, and metabolized by plants. Exposure to PAEs induces multiple adverse effects in aquatic plants, including growth perturbation, structural damage, disruption of photosynthesis, oxidative damage, and potential genotoxicity. High-throughput omics techniques further reveal the underlying toxicity molecular mechanisms of how PAEs disrupt plants on the transcription, protein, and metabolism levels. Finally, this review proposes that future studies should evaluate the interactions between plants and PAEs with a focus on long-term exposure to environmental PAE concentrations, the effects of PAE alternatives, and human health risks via the intake of plant-based foods.


Asunto(s)
Ésteres , Ácidos Ftálicos , Plantas , Contaminantes Químicos del Agua , Ácidos Ftálicos/toxicidad , Ácidos Ftálicos/metabolismo , Ésteres/toxicidad , Plantas/efectos de los fármacos , Plantas/metabolismo , Contaminantes Químicos del Agua/toxicidad
8.
J Hazard Mater ; 475: 134913, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38880048

RESUMEN

Photoinitiators (PIs) are chemical additives that generate active substances, such as free radicals to initiate photopolymerization. Traditionally, polymerization has been considered a green technique that seldomly generates contaminants. However, many researches have confirmed toxicity effects of PIs, such as carcinogenicity, cytotoxicity, endocrine disrupting effects. Surprisingly, we found high levels of PIs in indoor dust. Our analysis revealed comparable levels of PIs in dust from printing shops (geometric mean, GM: 1.33 ×103 ng/g) and control environments (GM: 874 ng/g), underscoring the widespread presence of PIs across various settings. Alarmingly, in dust samples from nail salons, PIs were detected at total concentrations ranging from 610 to 1.04 × 107 ng/g (GM: 1.87 ×105 ng/g), significantly exceeding those in the control environments (GM: 1.43 ×103 ng/g). Nail salon workers' occupational exposure to PIs through dust ingestion was estimated at 4.86 ng/kg body weight/day. Additionally, an in vitro simulated digestion test suggested that between 10 % and 42 % of PIs present in ingested dust could become bioaccessible to humans. This is the first study to report on PIs in the specific environments of nail salons and printing shops. This study highlights the urgent need for public awareness regarding the potential health risks posed by PIs to occupational workers, marking an important step towards our understanding of environmental pollution caused by PIs.


Asunto(s)
Polvo , Exposición Profesional , Polvo/análisis , Exposición Profesional/análisis , Humanos , Medición de Riesgo , Contaminación del Aire Interior/análisis , Industria de la Belleza , Contaminantes Ocupacionales del Aire/análisis , Contaminantes Ocupacionales del Aire/toxicidad
9.
J Agric Food Chem ; 72(32): 18171-18180, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39092884

RESUMEN

Conventional lateral flow immunoassay (LFIA) usually suffers from poor antimatrix interference, unsatisfactory sensitivity, and lack of quantitative ability for target analyte detection in food matrices. In response to these limits, here, multifunctional nanomaterial ZnFe2O4 nanoparticles (ZFOs) were developed and integrated into LFIA for powerful magnetic separation/enrichment and colorimetric/photothermal target sensing. Under optimum conditions, the detection for clenbuterol (CL) with magnetic enrichment achieves 9-fold higher sensitivity compared to that without enrichment and 162-fold higher sensitivity compared to that based on traditional colloidal golds. Attributing the improved performances of ZFOs, CL can be detected at ultralow levels in pork and milk with 10 min of immunoreaction time. The vLODs were 0.01 µg kg-1 for two modes, and the cutoff values of CL were about 5 and 3 µg kg-1, respectively. More importantly, the enrichment ZFO-mediated LFIA (ZE-LFIA) exhibits a similar limit of detection (LOD) in both buffer solution and food matrix, demonstrating a universal resistance to the food matrix. The multitudinous performance merits of this ZE-LFIA with high sensitivity, matrix tolerance, accuracy, and specificity have ensured a broad application potential for target detection of clenbuterol and can serve as an experience for other veterinary drug residues' detection.


Asunto(s)
Clenbuterol , Contaminación de Alimentos , Límite de Detección , Leche , Animales , Inmunoensayo/métodos , Inmunoensayo/instrumentación , Porcinos , Clenbuterol/análisis , Contaminación de Alimentos/análisis , Leche/química
10.
J Hazard Mater ; 470: 134113, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38565021

RESUMEN

Photo-induced degradation of dimethylmercury (DMHg) is considered to be an important source for the generation of methylmercury (MMHg). However, studies on DMHg photodegradation are scarce, and it is even debatable about whether DMHg can be degraded in natural waters. Herein, we found that both DMHg and MMHg could be photodegraded in three natural waters collected from the Yellow River Delta, while in pure water only DMHg photodegradation occurred under visible light irradiation. The effects of different environmental factors on DMHg photodegradation were investigated, and the underlying mechanisms were elucidated by density functional theory calculations and a series of control experiments. Our findings revealed that the DMHg degradation rate was higher in the tidal creek water compared to Yellow River, Yan Lake, and purified water. NO3-, NO2-, and DOM could promote the photodegradation with DOM and NO3- showing particularly strong positive effects. Different light sources were employed, and UV light was found to be more effective in DMHg photodegradation. Moreover, MMHg was detected during the photodegradation of DMHg, confirming that the photochemical demethylation of DMHg is a source of MMHg in sunlit water. This work may provide a novel mechanistic insight into the DMHg photodegradation in natural waters and enrich the study of the global biogeochemical cycle of Hg.


Asunto(s)
Compuestos de Metilmercurio , Fotólisis , Contaminantes Químicos del Agua , Compuestos de Metilmercurio/química , Compuestos de Metilmercurio/análisis , Compuestos de Metilmercurio/efectos de la radiación , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/efectos de la radiación , Contaminantes Químicos del Agua/análisis , Luz , Rayos Ultravioleta , Nitratos/química , Nitratos/análisis , Ríos/química
11.
Chem Commun (Camb) ; 59(50): 7704-7716, 2023 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-37248748

RESUMEN

Plasmonic nanomaterials have spurred significant research interest in enhanced solar-driven photocatalysis due to their strong localized surface plasmon resonance (LSPR). As this rapid-developing research area has begun to raise and answer fundamental questions that determine the photocatalytic performance of plasmonic photocatalysts, it is an opportune time to evaluate the advancement and propose future trajectories. We first outline the fundamentals of LSPR, including its excitation, decay, and influencing factors. We then discuss three main enhancement mechanisms and their applicable scenarios for plasmonic photocatalysis. We then critically assess the recent works performed by our groups concerning plasmon-enhanced photocatalytic reactions. By introducing related works from other researchers, we demonstrate our contributions to the advancements of plasmonic photocatalysis. Finally, we discuss the current challenges and suggest future directions in three aspects: material development, mechanism exploration, and application extension. It is anticipated to delineate the state-of-the-art and direct future research in plasmon-enhanced value-added chemical transformations.

12.
J Chromatogr A ; 1712: 464472, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-37924619

RESUMEN

Transformations between dimethylmercury (DMHg) and other mercury (Hg) species have been one of the critical knowledge gaps in the Hg global biogeochemical cycle due to the lack of detailed studies. The preparation and measurement of DMHg are challenging due to the high toxicity and volatility of DMHg. In this work, we invented a new DMHg generator for successfully preparing high-purity DMHg in a highly controllable and safe way. The DMHg could be spontaneously volatilized and diffused from the original preparation solution to the solution to be studied. The parameters for generating DMHg were optimized to be the pH value of 4.0 with a MeCo/Hg2+ molar ratio of 10 at 20 °C. The following measurement method of DMHg in the presence of various species of Hg was also investigated and optimized. Hg0 and DMHg could be separated effectively with the carrier gas flow rate of 15 mL min-1 and the gas chromatography column temperature of 30 °C. The interferences of Hg0, monomethylmercury and other species were excluded by systematic control experiments. A sensitive and reliable approach for quantifying trace DMHg in water was developed. Under the optimal conditions, the limits of detection for Hg0, MMHg and DMHg were 0.03, 0.002 and 0.024 ng L-1, respectively, with the relative standard deviation below 8.2%. The developed method was validated by the determination Hg species of different natural water samples. This work is expected to provide a new and safe strategy for DMHg preparation and a verified method for DMHg measurement.


Asunto(s)
Mercurio , Compuestos de Metilmercurio , Contaminantes Químicos del Agua , Espectrometría de Fluorescencia , Cromatografía de Gases y Espectrometría de Masas , Contaminantes Químicos del Agua/análisis , Compuestos de Metilmercurio/análisis , Mercurio/análisis , Agua
13.
Zhongguo Zhong Yao Za Zhi ; 37(22): 3354-60, 2012 Nov.
Artículo en Zh | MEDLINE | ID: mdl-23373201

RESUMEN

On the basis of a sysmatic survey on literatures, this essay summarized the studies on chemical constituents and pharmacological activity of Curcuma wenyujin. According to statistics, the reports for chemical constituents of the plant were mainly concentrated between 2007 and 2010. So far, totally 82 compounds were reported, including 57 sesquiterpenoids, 6 diterpenoids, 6 monoterpenes and 10 other components. Particularly, 23 compounds were new. Studies on its pharmacological activity covered antitumor, anti-inflammatory, analgesic, hepatoprotective, antioxidant, antithrombotic and antithrombosis. This essay summarized its chemical constituents and pharmacological activity, in order to facilitate its studies, development and utilization.


Asunto(s)
Curcuma/química , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Animales , Humanos , Estructura Molecular
14.
Sci Total Environ ; 820: 153334, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35074376

RESUMEN

Inspired by the classic ion-exchange reaction, a single phase material of Mg0.66Al0.34(OH)2(Mo3S13)0.03(NO3)0.14(CO3)0.07·H2O (Mo3S13-LDH) was masterly constructed by intercalating Mo3S132- into the MgAl-LDH gallery. Prepared Mo3S13-LDH displays excellent binding affinity and high selectivity for Ag(I) and Hg(II) in a mixed solution, in which an apparent selectivity order of Hg(II) > Ag(I) ≫ Pb(II), Cu(II), Ni(II), Co(II), Cd(II), and Mn(II) is observed. Enormous capture capacities (qmAg = 446.4 mg/g, qmHg = 354.6 mg/g) and fast equilibration time (within 60 min) place Mo3S13-LDH in the upper ranks of materials for such removal. For oxoanions, As(III) (HAsO32-) and Cr(VI) (CrO42-) can be specifically trapped by Mo3S13-LDH with comparable loading ability (qmAs = 61.8 mg/g, qmCr = 90.6 mg/g) in the coexistence of multiple interfering anions. Notably, high Hg(II) and Cr(VI) concentrations are finally reduced below the safe limit of drinking water. The excellent capture capacity of Mo3S13-LDH benefits from the rational design by following two aspects: (i) the multiple sulfur ligands in Mo3S132- groups give place to various capture modes and different affinity orders for target ions, and (ii) large-sized Mo3S132- groups widen the interlayer spacing of LDH, thereby accelerating the mass transfer process. Furthermore, the satisfactory structural stability of Mo3S13-LDH is also reflected through the unchanged hexagonal prismatic shape after adsorption. All of these highlight the great potential of Mo3S13-LDH for the application in water remediation.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Adsorción , Cromo , Cinética , Agua , Contaminantes Químicos del Agua/análisis
15.
Mater Horiz ; 9(7): 1978-1983, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-35603715

RESUMEN

Piezocatalysis, the process of directly converting mechanical energy into chemical energy, has emerged as a promising alternative strategy for green H2 production. Nevertheless, conventional inorganic piezoelectric materials suffer from limited structural tailorability and small surface area, which greatly impedes their mechanically driven catalytic efficiency. Herein, we design and fabricate a novel UiO-66(Zr)-F4 metal-organic framework (MOF) nanosheet for piezocatalytic water splitting, with the highest H2 evolution rate reaching 178.5 µmol g-1 within 5 h under ultrasonic vibration excitation (110 W, 40 kHz), far exceeding that of the original UiO-66 host. A reduced bandgap from 2.78 to 2.43 eV is achieved after introducing a fluorinated ligand. Piezoresponse force microscopy measurements demonstrate a much stronger piezoelectric response for UiO-66(Zr)-F4, which may result from the polarity of the introduced fluorinated ligand. This work highlights the potential of MOF-based porous piezoelectric nanomaterials in harvesting mechanical energy to drive chemical reactions such as water splitting.

16.
J Med Chem ; 64(11): 7839-7852, 2021 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-34038131

RESUMEN

Inspired by the success of dual-targeting drugs, especially bispecific antibodies, we propose to combine the concept of proteolysis targeting chimera (PROTAC) and dual targeting to design and synthesize dual PROTAC molecules with the function of degrading two completely different types of targets simultaneously. A library of novel dual-targeting PROTAC molecules has been rationally designed and prepared. A convergent synthetic strategy has been utilized to achieve high synthetic efficiency. These dual PROTAC structures are characterized using trifunctional natural amino acids as star-type core linkers to connect two independent inhibitors and E3 ligands together. In this study, gefitinib, olaparib, and CRBN or VHL E3 ligands were used as substrates to synthesize novel dual PROTACs. They successfully degraded both the epidermal growth factor receptor (EGFR) and poly(ADP-ribose) polymerase (PARP) simultaneously in cancer cells. Being the first successful example of dual PROTACs, this technique will greatly widen the range of application of the PROTAC method and open up a new field for drug discovery.


Asunto(s)
Diseño de Fármacos , Receptores ErbB/metabolismo , Poli(ADP-Ribosa) Polimerasas/metabolismo , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteolisis/efectos de los fármacos , Proteínas Adaptadoras Transductoras de Señales/química , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Gefitinib/química , Humanos , Ligandos , Ftalazinas/química , Piperazinas/química , Complejo de la Endopetidasa Proteasomal/genética , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Ubiquitina-Proteína Ligasas/química , Ubiquitina-Proteína Ligasas/metabolismo
17.
Nat Commun ; 12(1): 1231, 2021 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-33623017

RESUMEN

Conversion of clean solar energy to chemical fuels is one of the promising and up-and-coming applications of metal-organic frameworks. However, fast recombination of photogenerated charge carriers in these frameworks remains the most significant limitation for their photocatalytic application. Although the construction of homojunctions is a promising solution, it remains very challenging to synthesize them. Herein, we report a well-defined hierarchical homojunction based on metal-organic frameworks via a facile one-pot synthesis route directed by hollow transition metal nanoparticles. The homojunction is enabled by two concentric stacked nanoplates with slightly different crystal phases. The enhanced charge separation in the homojunction was visualized by in-situ surface photovoltage microscopy. Moreover, the as-prepared nanostacks displayed a visible-light-driven carbon dioxide reduction with very high carbon monooxide selectivity, and excellent stability. Our work provides a powerful platform to synthesize capable metal-organic framework complexes and sheds light on the hierarchical structure-function relationships of metal-organic frameworks.

18.
Zhongguo Zhong Yao Za Zhi ; 35(16): 2106-9, 2010 Aug.
Artículo en Zh | MEDLINE | ID: mdl-21046740

RESUMEN

OBJECTIVE: To establish and revise the quality specification of Curcumae Radix. METHOD: TLC identification was carried out by the method in Appendix VI B in Chinese pharmacopoeia (2005th Edition) and the contents of volatile oil was determined by the method describing in Appendix XD. RESULT: Twenty-four Samples from four different curcuma species were performed TLC qualitative analysis and volatile determination, respectively. CONCLUSION: The established method can be used for the quality control of Curcumae Radix.


Asunto(s)
Curcuma/química , Medicamentos Herbarios Chinos/análisis , Cromatografía en Capa Delgada , Aceites Volátiles/análisis
19.
Zhongguo Zhong Yao Za Zhi ; 35(19): 2590-3, 2010 Oct.
Artículo en Zh | MEDLINE | ID: mdl-21174771

RESUMEN

OBJECTIVE: To compare the contents and composition of volatile oil of Wenyujin (steamed root of Curcuma wenyujin) Wenezhu (steamed rhieome of Curcuma wenyujin) and Pianjianghuang (rhizome of Curcuma wenyujin). METHOD: The volatile oils of three herbal medicines obtained by steam distillation were determined according to the method described in the appendix XD in Chinese pharmacopoeia and identified by GC-MS. RESULT: The average contents of volatile oil of Wenyujin, Wenezhu and Pianjianghuang were 0.56, 1.99 and 0.94 microL x g(-1), respectively. A total of 60 compounds were identified by GC-MS. The amounts of chemical components separated and identified in Wenyujin, Wenezhu and Pianjianghuang were 41, 41 and 40, respectively. Three medicines share a great deal of similarity, chemically and genetically. Low boiling point essential oil compositions Wenyujin and Wenezhu were similar. While the higher boiling point essential oil compositions of Wenyujin and Wenezhu were similar. And the essential oil compositions of Wenyujin and Pianjianghuang were distinct. CONCLUSION: Although coming from the same origin, the composition of essential oil from different part of the plant or various process were discrepant, which lead to rather distinct clinical efficacy.


Asunto(s)
Curcuma/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Medicina de Hierbas , Extractos Vegetales/química , Rizoma/química , Aceites Volátiles/química , Raíces de Plantas/química , Control de Calidad
20.
J Mater Chem B ; 8(35): 7856-7879, 2020 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-32749426

RESUMEN

Near infrared (NIR)-excitable and NIR-emitting probes have fuelled advances in biomedical applications owing to their power in enabling deep tissue imaging, offering high image contrast and reducing phototoxicity. There are essentially three NIR biological windows, i.e., 700-950 nm (NIR I), 1000-1350 nm (NIR II) and 1550-1870 nm (NIR III). Recently emerging optical probes that can be excited by an 800 nm laser and emit in the NIR II or III windows, denoted as NIR I-to-NIR II/III, are particularly attractive. That is because the longer wavelengths in the NIR II and NIR III windows offer deeper penetration and higher signal to noise ratio than those in the NIR I window. NIR imaging has indeed become a quickly evolving field and, simultaneously, stimulated the further development of new classes of NIR I-to-NIR II/III inorganic fluorescent probes, which include PbS, Ag2S-based quantum dots (QDs) and rare earth (RE) doped NPs (RENPs) that possess quite diverse optical properties and follow different emission mechanisms. This review summarizes the recent progress on material merits, synthetic routes, the rational choice of excitation in the NIR I window, NIR II/III emission optimization, and surface modification of aforementioned fluorescent probes. We also introduce the latest notable accomplishments enabled by these probes in fluorescence imaging, lifetime-based multiplexed imaging and photothermal therapy (PTT), together with a critical discussion of forthcoming challenges and perspectives for clinic use.


Asunto(s)
Colorantes Fluorescentes , Rayos Infrarrojos , Compuestos Inorgánicos , Investigación Biomédica , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/química , Compuestos Inorgánicos/síntesis química , Compuestos Inorgánicos/química
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