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1.
Artigo em Inglês | MEDLINE | ID: mdl-32708499

RESUMO

With a shifting climate pattern and enhancement of human activities, coastal areas are exposed to threats of groundwater environmental issues. This work takes the eastern coast of Laizhou Bay as a research area to study the response of a coastal groundwater system to natural and human impacts with a combination of statistical, hydrogeochemical, and fuzzy classification methods. First, the groundwater level dynamics from 1980 to 2017 were analyzed. The average annual groundwater level dropped 13.16 m with a descent rate of 0.379 m/a. The main external environmental factors that affected the groundwater level were extracted, including natural factors (rainfall and temperature), as well as human activities (irrigated area, water-saving irrigated area, sown area of high-water-consumption crops, etc.). Back-propagation artificial neural network was used to model the response of groundwater level to the above driving factors, and sensitivity analysis was conducted to measure the extent of impact of these factors on groundwater level. The results verified that human factors including irrigated area and water-saving irrigated area were the most important influencing factors on groundwater level dynamics, followed by annual precipitation. Further, groundwater samples were collected over the study area to analyze the groundwater hydrogeochemical signatures. With the hydrochemical diagrams and ion ratios, the formation of groundwater, the sources of groundwater components, and the main hydrogeochemical processes controlling the groundwater evolution were discussed to understand the natural background of groundwater environment. The fuzzy C-means clustering method was adopted to classify the groundwater samples into four clusters based on their hydrochemical characteristics to reveal the spatial variation of groundwater quality in the research area. Each cluster was spatially continuous, and there were great differences in groundwater hydrochemical and pollution characteristics between different clusters. The natural and human factors resulted in this difference were discussed based on the natural background of the groundwater environment, and the types and intensity of human activity.

2.
Artigo em Inglês | MEDLINE | ID: mdl-32252526

RESUMO

Two three-dimensional symmetric tetraphenylbutadiene derivatives decorated with diphenylamine or triphenylamine fragments are first prepared for use as hole-transporting materials (HTMs) in perovskite solar cells (PSCs). The HTMs are acquired using straightforward synthetic methods and facile purification techniques. The thermal stability, photophysical properties, electrochemical behaviors, computational study, hole mobility, X-ray diffraction, hole transfer dynamics, hydrophobicity, surface morphology, and photovoltaic performances of the HTMs are discussed. The highest power conversion efficiency (PCE) of CJ-04-based cell is 13.75%, which is increased to 20.06% when CJ-03 is used as HTM, superior to the PCE of the cell based on 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD) (18.90%). The preparation cost of CJ-03 accounts for merely 23.1% of the price of commercial spiro-OMeTAD, while the concentration of CJ-03 solution used in the device fabrication (60.0 mg mL-1) is lower compared with that of the spiro-OMeTAD solution (72.3 mg mL-1). These results corroborate that the screw-like HTMs with a highly distorted configuration are facilely available and promising candidates for PSCs. More importantly, a practical solution is proposed to achieve moderate charge mobility and good film-formation ability of the HTMs simultaneously.

3.
Anal Chem ; 92(4): 2953-2960, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-31941275

RESUMO

Self-accumulation of amyloid-ß protein (Aß) into insoluble fibrils is the major hallmark of Alzheimer's disease. Real-time monitoring of fibril growth is essential for clarifying the mechanism underlying aggregation and discovering therapeutic targets. A variety of approaches including NMR, electron microscopy (EM), atomic force microscopy (AFM), and total internal reflection fluorescence microscopy (TIRFM) have been explored to monitor the fibril growth or reveal morphology of Aß aggregates. However, none of the methods allow real-time observation under physiological conditions while without any perturbations. Here, we present a fluorescent probe [Ru(phen)2(fipc)]2+ (Ru-fipc) (phen = 1,10-phenanthroline, fipc = 5-fluoro-N-(1,10-phenanthrolin-5-yl)-1H-indole-2-carboxamide) that can bind to all the Aß forms, i.e., monomers, oligomers, and fibrils, while not perturbing aggregation. Using this probe in combination with laser confocal microscopy, the entire aggregation process could be clearly and exactly imaged at the single fibril level. The reliability of Ru-fipc was confirmed based on colocalization with thioflavin T (ThT). Importantly, Ru-fipc can be used to monitor the very early nucleation and oligomerization process, which is thought to be a critical step in the development of neurotoxicity while it cannot be visualized with ThT. To our knowledge, this is the first fluorescent probe developed for real-time monitoring of Aß aggregation, especially for the very early assembly stage, in solution with minimal perturbation. This method is suitable for in vitro and in vivo studies. We believe this would provide a valuable complementary tool for the study of pathogenesis and discovery of therapeutic targets of neurodegenerative diseases.

4.
Anal Chim Acta ; 1097: 144-152, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-31910954

RESUMO

Disruption of copper homeostasis is associated with a number of severe diseases including Alzheimer's disease (AD), Parkinson's disease (PD), Wilson's disease, and Menkes syndrome. Given this association, the detection and capture of Cu2+ in biological fluids and tissues may provide a new direction for the diagnosis and treatment of related disorders. The current analytical approaches, however, are challenging due to the high cost, complexity, and long time required to prepare and analyze samples. Here, we report a novel salen ligand, namely N,N'-(1,2-phenylene)bis(1-(1H-imidazol-4-yl)methanimine) (pimi), which can readily detect and concurrently capture Cu2+ from aqueous as well as biological mediums. Pimi can selectively and specifically detect Cu2+ from biofluid and cellular samples with rapid ccresponse time (<3 s) and an ultra-sensitive detecting limit (2.7 nM). More importantly, pimi showed excellent environmental tolerance and had a very wide pH range for detecting Cu2+ in a variety of biological samples. Attributed to the strong binding affinity and selectivity towards Cu2+, pimi was found to capture Cu2+ ions from Cu-Aß complexes, thus inhibiting copper-induced aggregation of Aß and protecting neuronal cells from the toxicity of aggregated Aß. These results provide a compelling starting point for further fine-tuning of salen-based chemosensor for the diagnosis and treatment of diseases associated with the hyperaccumulation of copper.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Cobre/análise , Cobre/toxicidade , Avaliação Pré-Clínica de Medicamentos , Etilenodiaminas/química , Agregados Proteicos/efeitos dos fármacos , Agregação Patológica de Proteínas/tratamento farmacológico , Peptídeos beta-Amiloides/antagonistas & inibidores , Linhagem Celular Tumoral , Humanos , Concentração de Íons de Hidrogênio , Íons/análise , Íons/farmacologia
5.
J Inorg Biochem ; 203: 110929, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31786439

RESUMO

The accumulation of the ß-amyloid (Aß) aggregates induced by Cu2+/Zn2+ in conjunction with toxicity is closely related to Alzheimer's disease (AD). Herein, we intended to improve the efficiency and selectivity of traditional chelator ethylenediaminetetraacetic acid (EDTA) combined with a fluorescent group 4-aminosalicylic acid (4-ASA)to acquire a novel potential chelator 4,4'-((2,2'-(ethane-1,2-diylbis((carboxymethyl)azanediyl))bis(acetyl))bis(azanediyl))bis(2-hydroxybenzoic acid) (EDTA-ASA) capable of disaggregating Aß-Cu(II)/ Zn(II) aggregates. EDTA-ASA combines 4-ASA as fluorophore and multidentate amino nitrogen, hydroxyl and carboxyl groups to chelate Cu2+ from Aß-Cu (II) aggregates. The specific selectivity of EDTA-ASA towards Cu2+ in Tris-HCl buffer solution was investigated by fluorescence measurements. It exhibits high recognition towards Cu2+ with no significant interference of other competitive metal ions, which overcomes the deficiencies of EDTA. Importantly, the binding sites and binding mode for Cu2+ were clarified through DFT calculations. The thioflavin-T (ThT) fluorescence analyses and transmission electron microscopy (TEM) results have revealed EDTA-ASA exhibited an enhanced disaggregation capability on Aß-Cu (II)/Zn (II) aggregates in comparison to EDTA. The Cu2+ chelating affinity was sufficient for EDTA-ASA to sequester Cu2+ from Aß-Cu (II) aggregates.

6.
Anal Chim Acta ; 1094: 122-129, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31761038

RESUMO

Hypochlorite (HClO) is involved in various physiological and pathological processes as well as regulation of lysosomal functions. Thus, it is appreciated to develop efficient molecule tools for precisely detecting HClO in lysosomes. Although several lysosomal-targetable fluorogenic probes for HClO have been developed to date, they still suffered from the discounted sensing performance under lysosomal acidic condition. Herein, on the basis of the "AND" logic gate strategy, a novel dual-activatable fluorogenic probe CS has been rationally designed by simultaneously incorporating HClO recognition site and pH-sensitive group with lysosomal-targetable characteristic into a coumarin fluorophore. Different from the single-activated ones previously reported, CS exhibited good sensitivity, high specificity and fast response towards HClO under the acidic conditions but was out of operation in the neutral or alkaline environment. Importantly, it had been successfully applied for spatial-resolution imaging of exogenous or endogenous HClO in lysosomes.


Assuntos
Cumarínicos/química , Corantes Fluorescentes/química , Ácido Hipocloroso/análise , Lisossomos/metabolismo , Cumarínicos/síntese química , Cumarínicos/toxicidade , Teoria da Densidade Funcional , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Limite de Detecção , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Modelos Químicos , Espectrometria de Fluorescência/métodos
7.
Chirality ; 32(3): 324-333, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31877236

RESUMO

A simple and sensitive method has been established based on pass-through cleanup and high-performance liquid chromatography quadrupole-orbitrap mass spectrometry (HPLC-Q/Orbitrap MS) for the simultaneous determination of ten aminoglycosides (AGs) in aquatic feeds. The extraction solution and cleanup procedure had been optimized, and good sensitivity, accuracy, and precision were obtained. The calibration curves of AGs were linearity (R2 > 0.99) in the range of 2.0 to 200 µg/L (or 5.0 to 500 µg/L). The limits of detection of AGs were between 10 and 25 µg/kg. The recoveries of AGs ranged from 74.9% to 94.3%, and the intraday and interday relative standard deviations were less than 15%. Finally, this method was successfully applied to determine ten AGs in 30 aquatic feed samples. It might be the first time to use pass-through cleanup approach combined with HPLC-Q/Orbitrap MS method for AGs determination in aquatic feed samples.

8.
Nat Commun ; 10(1): 5762, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31848349

RESUMO

Perfluorinated alkyl substances, such as perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA), are toxic materials that are known to globally contaminate water, air, and soil resources. Strategies for the simultaneous detection and removal of these compounds are desired to address this emerging health and environmental issue. Herein, we develop a type of guanidinocalix[5]arene that can selectively and strongly bind to PFOS and PFOA, which we use to demonstrate the sensitive and quantitative detection of these compounds in contaminated water through a fluorescent indicator displacement assay. Moreover, by co-assembling iron oxide nanoparticle with the amphiphilic guanidinocalix[5]arene, we are able to use simple magnetic absorption and filtration to efficiently remove PFOS and PFOA from contaminated water. This supramolecular approach that uses both molecular recognition and self-assembly of macrocyclic amphiphiles is promising for the detection and remediation of water pollution.


Assuntos
Ácidos Alcanossulfônicos/análise , Calixarenos/química , Caprilatos/análise , Fluorcarbonetos/análise , Tensoativos/química , Poluentes Químicos da Água/análise , Absorção Fisico-Química , Ácidos Alcanossulfônicos/isolamento & purificação , Caprilatos/isolamento & purificação , Monitorização de Parâmetros Ecológicos/métodos , Poluição Ambiental/prevenção & controle , Compostos Férricos/química , Filtração/instrumentação , Filtração/métodos , Fluorcarbonetos/isolamento & purificação , Nanopartículas de Magnetita/química , Água/análise , Água/química , Poluentes Químicos da Água/isolamento & purificação , Poluição Química da Água/prevenção & controle
9.
Chem Commun (Camb) ; 55(95): 14387-14390, 2019 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-31723950

RESUMO

We designed a tandem stimuli-responsive assembly based on a guanidinium-modified calix[5]arene (GC5A-6C) and eosin Y modified hyaluronic acid (EY-HA), which showed hyaluronidase-triggered disassembly and ATP-activated release of EY. Both hyaluronidase and ATP are tumor biomarkers, and therefore, the present system shows potential in precision delivery with respect to tumor phototheranostics.


Assuntos
Trifosfato de Adenosina/metabolismo , Calixarenos/metabolismo , Amarelo de Eosina-(YS)/metabolismo , Guanidina/metabolismo , Ácido Hialurônico/metabolismo , Hialuronoglucosaminidase/metabolismo , Trifosfato de Adenosina/química , Biomarcadores Tumorais/química , Biomarcadores Tumorais/metabolismo , Calixarenos/química , Amarelo de Eosina-(YS)/química , Guanidina/química , Humanos , Ácido Hialurônico/química , Hialuronoglucosaminidase/química , Substâncias Macromoleculares/química , Substâncias Macromoleculares/metabolismo , Polímeros/química , Polímeros/metabolismo , Nanomedicina Teranóstica , Microambiente Tumoral
10.
Medicine (Baltimore) ; 98(48): e18025, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31770216

RESUMO

INTRODUCTION: Sepsis is a physiological, pathological, and biochemical syndrome caused by infection. Acupuncture may be useful for sepsis. This systematic review aims to assess the efficacy and safety of acupuncture as a complementary therapy for sepsis. METHODS AND ANALYSIS: We will search PubMed, EMBASE, the Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure (CNKI), Wan Fang Database, Chinese Biomedicine (CBM) database, VIP database, and TCM Literature Analysis and Retrieval Database from inception to October 31, 2019 to identify any eligible study. We include all randomized controlled trials (RCTs) without any limitation of blinding or publication language, exclude cohort studies and case reports. Two reviewers will independently select studies, extract and manage data. The primary outcomes include the mortality at 28 days, acute physiology, and chronic health evaluation II scores. The secondary outcomes include the tumor necrosis factor α (TNF-α) counts, interleukin 6 (IL-6) counts, interleukin 10 (IL-10) counts, procalcitonin (PCT), lactic acid, the level of T cell subsets (CD3+, CD4+, CD8+, CD4+/CD8+), monocytes of human leukocyte antigen DR (HLA-DR), C-reactive protein (CRP), the numeration of leukocyte, intra-abdominal pressure, and adverse events or reactions. Statistical analyses will be performed using the Review Manager V.5.3 and R packages Metafor. We will use the Cochrane risk of bias tool for randomized trials to assess the risk of bias of included studies. ETHICS AND DISSEMINATION: This study will not involve personal information. Ethical approval will not be required. We will publish the results in a peer-reviewed journal. PROSPERO TRIAL REGISTRATION NUMBER: CRD42019141491.


Assuntos
Terapia por Acupuntura/métodos , Sepse/terapia , APACHE , Proteína C-Reativa/análise , Antígenos HLA-DR/sangue , Humanos , Interleucina-10/sangue , Interleucina-6/sangue , Ácido Láctico/sangue , Contagem de Leucócitos , Metanálise como Assunto , Pró-Calcitonina/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Sepse/sangue , Sepse/mortalidade , Revisões Sistemáticas como Assunto , Subpopulações de Linfócitos T/metabolismo , Resultado do Tratamento , Fator de Necrose Tumoral alfa/sangue
11.
Glob Chall ; 3(10): 1900034, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31592334

RESUMO

Three novel organic dyes coded as FHD4-1, FHD4-2, and FHD4-3 featuring spiro[dibenzo[3,4:6,7]cyclohepta[1,2-b]quinoxaline-10,9'-fluorene] (SDBQX) moieties are designed to inhibit dye aggregation to improve the performance of dye-sensitized solar cells (DSSCs). The consistent absorption onsets of FHD4-1, FHD4-2, and FHD4-3 in solutions and adsorbed on TiO2 films indicate that these dyes are aggregation-free dyes. Therefore, coadsorption with chenodeoxycholic acid (CDCA) of these three dyes reduces the performance of DSSCs because no inhibition effect for dye aggregation is needed, but, on the contrary, the dye loading amount is reduced after addition of CDCA.

12.
Micromachines (Basel) ; 10(10)2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618987

RESUMO

An anthracene aromatic unit was introduced into the phenylethynyl structure by a rigid acetylene linkage at the C-9 and C-10 positions via Sonogashira coupling reactions, resulting in a planar and straight-backbone molecule (9,10-bis((4-((3,7-dimethyloctyl)oxy) phenyl) ethynyl) anthracene) (BPEA). Thermogravimetric analysis demonstrated the good thermal stability of the BPEA. Photoluminescence analysis showed that a suitable expanded π-conjugation in the BPEA made its excitation band extend into the visible region, and an intense green emission was observed under blue-light excitation. A bright green light-emitting diode with an efficiency of 18.22 lm/w was fabricated by coating the organic phosphor onto a 460 nm-emitting InGaN chip. All the results indicate that BPEA is a useful green-emitting material which is efficiently excited by blue light, and therefore, that it could be applied in many fields without UV radiation.

13.
Environ Sci Pollut Res Int ; 26(32): 33146-33156, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31520380

RESUMO

Water level fluctuation zone (WLFZ) with changeable environmental conditions would affect the transport and release of nutrients in the sediment. To investigate the influence of long-term water level fluctuations on sediment phosphorus (P), a reservoir sediment partitioning method based on historical water level was developed and applied in the Biliuhe Reservoir. The reservoir sediment was divided into frequent fluctuation zone (FFZ), fluctuation zone of continuous droughts (DFZ), and continuously submerged zone (CSZ). Sediment cores in different zones were collected and P was analyzed. TP content in the surface sediment progressively increased from FFZ, DFZ, to CSZ except the 0-10-cm samples of D1, and TP content of sediment cores increased gradually with decreasing depth except D1 core. Ferric iron-bound P (Fe-P) and organic P (OP) exhibited uniform spatial variation with TP, while no clear patterns were found with regard to the other forms. Fe-P composed most of TP (54.67 ± 10.15%) and had a significant positive correlation with stable OP (5.55 ± 2.07%). The contributions of Fe-P, detrital apatite P (Det-P), and OP are stable among the four cores, indicating that the relationship between the various P forms is relatively stable despite variations in environmental conditions of WLFZ. The alternation of deposition and erosion under long-term water level fluctuation can promote P transport down-flow, which can be prevented by the continuous growth of plants in WLFZ. Thus, the reasonable use of the plant growth in WLFZ can control the P load of the reservoir.


Assuntos
Monitoramento Ambiental , Fósforo/análise , Poluentes Químicos da Água/análise , China , Água Doce , Sedimentos Geológicos , Ferro , Água
14.
Molecules ; 24(18)2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31533222

RESUMO

Multiclass screening of drugs with high resolution mass spectrometry is of great interest due to its high time-efficiency and excellent accuracy. A high-scale, fast screening method for pesticides in fishery drugs was established based on ultrahigh performance liquid chromatography tandem quadrupole-Orbitrap high-resolution mass spectrometer. The target compounds - were diluted in methanol and extracted by ultrasonic treatment, and the extracts were diluted with MeOH-water (1:1, v/v) and centrifuged to remove impurities. The chromatographic separation was performed on an Accucore aQ-MS column (100 mm × 2.1 mm, 2.6 µm) with gradient elution using 0.1% formic acid in water (containing 5 mmol/L ammonium formate) and 0.1% formic acid in methanol (containing 5 mmol/L ammonium formate) in Full Scan/dd-MS2 (TopN) scan mode. A screening database, including mass spectrometric and chromatographic information, was established for identification of compounds. The screening detection limits of methods ranged between 1-500 mg/kg, the recoveries of real samples spiked with the concentration of 10 mg/kg and 100 mg/kg standard mixture ranged from 70% to 110% for more than sixty compounds, and the relative standard deviations (RSDs) were less than 20%. The application of this method showed that target pesticides were screened out in 10 samples out of 21 practical samples, in which the banned pesticide chlorpyrifos were detected in 3 out of the 10 samples.


Assuntos
Cromatografia Líquida de Alta Pressão , Peixes , Contaminação de Alimentos/análise , Praguicidas/análise , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida de Alta Pressão/métodos , Pesqueiros , Análise de Alimentos/métodos , Espectrometria de Massas em Tandem/métodos
15.
Theranostics ; 9(16): 4624-4632, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31367245

RESUMO

Detection and quantification of trimethylamine N-oxide (TMAO), a metabolite from gut microbial, is important for the disease diagnosis such as atherosclerosis, thrombosis and colorectal cancer. In this study, a novel method was established for the sensing and quantitative detection of TMAO via molecular recognition of guanidinium-modified calixarene from complex matrix. Methods: Various macrocycles were tested for their abilities to serve as an artificial TMAO receptor. Using the optimized receptor, we developed an indicator displacement assay (IDA) for the facile fluorescence detection of TMAO. The quantification of TMAO was accomplished by the established calibration line after excluding the interference from the various interfering substances in artificial urine. Results: Among various macrocycles, water-soluble guanidinium-modified calix[5]arene (GC5A), which binds TMAO in submicromolar-level, was identified as the optimal artificial receptor for TMAO. With the aid of the GC5A•Fl (fluorescein) reporter pair, TMAO fluorescence "switch-on" sensing was achieved by IDA. The fluorescence intensity increased linearly with the elevated TMAO concentration. The detection was not significantly interfered by the various interfering substances. TMAO concentration in artificial urine was quantified using a calibration line with a detection limit of 28.88 ± 1.59 µM, within the biologically relevant low µM range. Furthermore, the GC5A•Fl reporter pair was successfully applied in analyzing human urine samples, by which a significant difference in fluorescence response was observed between the [normal + TMAO] and normal group. Conclusion: The proposed supramolecular approach provides a facile, low-cost and sensitive method for TMAO detection, which shows promise for tracking TMAO excretion in urine and studying chronic disease progression in humans.

16.
Inorg Chem ; 58(16): 10736-10742, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31390188

RESUMO

A new Cu4I4-cluster-based compound is constructed to show multifaceted photoluminescent attributes: (1) ultraviolet (UV)-excited thermo-, mechano-, and rigido-chromic phosphorescence by the OPA (one-photon absorption) pathway, due to the interchanging emissions from cluster-centered (3CC) and halide-to-ligand charge-transfer (3XLCT) excited triplet states, (2) the ability to convert X/γ-ray and near-infrared (NIR) radiation to visible-light emission, in which the heavy Cu4I4 cores serve as the efficient X/γ-PEA (photoelectric absorption) or NIR-TPA (two-photon absorption) trapper and convertor to photons in the visible spectrum from the same emissive triplet states as those produced by UV excitation. This all-in-one compound affords a highly integrated nanolab for understanding and exploiting a wide range of photophysical phenomena simultaneously and is further fabricated into fiber-coupled long-range, in situ cryogenic thermometer and poly(methyl methacrylate) (PMMA)-embedded monolith gel, providing access to advanced applications in multifunctional optical materials and devices.

17.
Cell Res ; 29(9): 778, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31395957

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

18.
Nat Prod Res ; : 1-6, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31359768

RESUMO

Two new compounds, corylifol H (1) and epi-bavacoumestan C (2), together with a new natural product named 8-geranyl daidzein (3), were isolated from the fruits of Cullen corylifolium (L.) Medik. (syn. of Psoralea corylifolia L.) by the targeted separation mode. The structures of these compounds were elucidated on the basis of spectroscopic methods and by comparison with literature properties. The anti-inflammatory effects of the two new compounds were also evaluated by activity assay in vitro. The results showed that compounds 1 and 2 inhibited nitric oxide production in LPS-activated RAW 264.7 macrophages in a dose dependent manner.

19.
Chemistry ; 25(51): 11903-11909, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31274212

RESUMO

Molecular or supramolecular level photoluminescence (PL) modulation combining chemical and photonic input/output signals together in an integrated system can provide potential high-density data memorizing and process functions intended for miniaturized devices and machines. Herein, a PL-responsive supramolecular coordination cage has been demonstrated for complex interactions with redox-active guests. PL signals of the cage can be switched and modulated by adding or retracting Fc derivatives or converting TTF into different oxidation states through chemical or photochemical pathways. As a result, reversible or stepwise PL responses are displayed by these host-guest systems because of the occurrence of photoinduced electron-transfer (PET) or fluorescence resonance energy transfer (FREnT) processes, providing unique nanodevice models bearing off/on logic gates or memristor-like sequential memory and Boolean operation functions.

20.
Cell Res ; 29(8): 666-679, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31201383

RESUMO

Oriented cell divisions are controlled by a conserved molecular cascade involving Gαi, LGN, and NuMA. Here, we show that NDP52 regulates spindle orientation via remodeling the polar cortical actin cytoskeleton. siRNA-mediated NDP52 suppression surprisingly revealed a ring-like compact subcortical F-actin architecture surrounding the spindle in prophase/prometaphase cells, which resulted in severe defects of astral microtubule growth and an aberrant spindle orientation. Remarkably, NDP52 recruited the actin assembly factor N-WASP and regulated the dynamics of the subcortical F-actin ring in mitotic cells. Mechanistically, NDP52 was found to bind to phosphatidic acid-containing vesicles, which absorbed cytoplasmic N-WASP to regulate local filamentous actin growth at the polar cortex. Our TIRFM analyses revealed that NDP52-containing vesicles anchored N-WASP and shortened the length of actin filaments in vitro. Based on these results we propose that NDP52-containing vesicles regulate cortical actin dynamics through N-WASP to accomplish a spatiotemporal regulation between astral microtubules and the actin network for proper spindle orientation and precise chromosome segregation. In this way, intracellular vesicles cooperate with microtubules and actin filaments to regulate proper mitotic progression. Since NDP52 is absent from yeast, we reason that metazoans have evolved an elaborate spindle positioning machinery to ensure accurate chromosome segregation in mitosis.

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