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1.
Nat Commun ; 15(1): 6266, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39048542

RESUMEN

Alcoholysis of poly(ethylene terephthalate) (PET) waste to produce monomers, including methanolysis to yield dimethyl terephthalate (DMT) and glycolysis to generate bis-2-hydroxyethyl terephthalate (BHET), is a promising strategy in PET waste management. Here, we introduce an efficient PET-alcoholysis approach utilizing an oxygen-vacancy (Vo)-rich catalyst under air, achieving space time yield (STY) of 505.2 gDMT·gcat-1·h-1 and 957.1 gBHET·gcat-1·h-1, these results represent 51-fold and 28-fold performance enhancements compared to reactions conducted under N2. In situ spectroscopy, in combination with density functional theory calculations, elucidates the reaction pathways of PET depolymerization. The process involves O2-assisted activation of CH3OH to form CH3OH* and OOH* species at Vo-Zn2+-O-Fe3+ sites, highlighting the critical role of Vo-Zn2+-O-Fe3+ sites in ester bond activation and C-O bond cleavage. Moreover, a life cycle assessment demonstrates the viability of our approach in closed-loop recycling, achieving 56.0% energy savings and 44.5% reduction in greenhouse-gas emissions. Notably, utilizing PET textile scrap further leads to 58.4% reduction in initial total operating costs. This research offers a sustainable solution to the challenge of PET waste accumulation.

2.
J Agric Food Chem ; 72(13): 7336-7343, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38508871

RESUMEN

Molecular docking has been widely applied in the discovery of new sweeteners, yet the interpretation of computational results sometimes remains difficult. Here, the interaction between the T1R2-T1R3 sweet taste receptor and 66 tasting compounds, including 26 sweet, 19 bitter, and 21 sour substances was investigated by batch molecular docking processes. Statistical analysis of the docking results generated two novel methods of interpreting taste properties. Quantitative correlation between relative sweetness (RS) and docking results created a multiparameter model to predict sweetness intensity, whose correlation coefficient r = 0.74 is much higher than r = 0.17 for the linear correlation model between sweetness and binding energy. The improved correlation indicated that docking results besides binding energy contain undiscovered information about the ligand-protein interaction. Qualitative discriminant analysis of different tasting molecules generated an uncorrelated linear discriminant analysis (UDLA) model, which achieved an overall 93.1% accuracy in discriminating the taste of molecules, with specific accuracy for verifying sweet, bitter, and sour compounds reaching 88.0%, 92.1%, and 100%. These unprecedented models provide a unique perspective for interpreting computational results and may inspire future research on sweetener discovery.


Asunto(s)
Edulcorantes , Gusto , Edulcorantes/química , Simulación del Acoplamiento Molecular , Receptores Acoplados a Proteínas G/metabolismo , Percepción del Gusto
4.
Analyst ; 149(1): 188-195, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38010128

RESUMEN

Herein, the electrodeposition of paracetamol oxide (PA ox) for the intelligent portable ratiometric detection of nicotine (NIC) and ethyl vanillin ß-D-glucoside (EVG) is reported. PA ox electrodeposited on a screen-printed carbon electrode (SPCE) was used as a new fixed state ratiometric reference probe. A portable electrochemical workstation combined with a smart phone was applied as an intelligent portable electrochemical sensing platform. The sensor was studied by scanning electron microscopy (SEM), Fourier transform infrared spectrophotometry (FT-IR), ultraviolet-visible spectrophotometry (UV-vis), theoretical calculation, chronoamperometry, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and square wave voltammetry (SWV). Under optimized conditions, the detection range of NIC is 10-200 µmol L-1, and the detection limit is 0.256 µmol L-1. The detection range of EVG was 10-180 µmol L-1, and the detection limit was 0.058 µmol L-1. The sensor can realize the real-time detection of NIC and EVG concentration in cigarette samples quickly and accurately, and has good anti-interference, repeatability and stability.


Asunto(s)
Acetaminofén , Nicotina , Óxidos , Espectroscopía Infrarroja por Transformada de Fourier , Galvanoplastia , Glucósidos , Electrodos , Técnicas Electroquímicas/métodos
5.
Technol Cancer Res Treat ; 22: 15330338231198347, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37649380

RESUMEN

PURPOSE: Colorectal cancer is one of the most common causes of cancer-related death, and its main site of metastasis is the liver. The surgical method used for metastases of colorectal cancer in the liver varies according to the lobe affected, as does the prognosis. However, there is a lack of relevant basic research. Therefore, a good animal model is needed for basic studies of metastases from colorectal cancer to the different lobes of the liver. METHODS: A CT26 colon cancer cell line transfected with a virus expressing green fluorescent protein was inoculated into BALB/C mice via the spleen. Tumor formation in the liver lobes was observed under a fluorescence microscope according to which portal vein branch was ligated and according to clamping time. The differential formation of metastatic lesions in the different lobes was then compared with physical anatomy. Serum samples were used to detect the changes in liver function postoperatively. RESULTS: Ligation and resection of the spleen 1 min after injection of the CT26 cells and release of the vessel clamp 1 min after splenectomy created an ideal tumor-bearing mouse model with little effect on liver function. Selective clamping of each portal vein branch and splenic injection of a CT26 cell line successfully established a selective liver lobe tumor-bearing model of colorectal cancer with distinct characteristics. CONCLUSION: This model provides an opportunity for investigation of the mechanisms of metastasis of colorectal cancer to different lobes of the liver and may provide a basis for clinical treatment.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Hepáticas , Animales , Ratones , Neoplasias Hepáticas/patología , Neoplasias Colorrectales/patología , Línea Celular Tumoral , Ratones Endogámicos BALB C
7.
JACS Au ; 1(2): 156-163, 2021 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-34467281

RESUMEN

Intelligent control over the handedness of circularly polarized luminescence (CPL) is of special significance in smart optoelectronics, information storage, and data encryption; however, it still remains a great challenge to rationally design a CPL material that displays reversible handedness inversion without changing the system composition. Herein, we show this comes true by coupling the two scenarios of Harata-Kodaka's rule on the same supramolecular platform of crystalline microtubes self-assembled from surfactant-cyclodextrin host-guest complexes. Upon coassembling a linear dye with its electronic transition dipole moment outside of the cavity of ß-CyD, the chirality transfer from the induced chirality of SDS in the SDS@2ß-CyD microtubes to the dye generates left-handed CPL at room temperature. Upon elevating temperature, the dye forms inclusion complex with ß-CyD, so that right-handed CPL is induced because the polar group of the dye is outside of the cavity of ß-CyD. This process is completely reversible. We envision that host-guest chemistry would be very promising in creating smart CPL inversion materials for a vast number of applications.

8.
ACS Appl Mater Interfaces ; 13(29): 34843-34850, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34254772

RESUMEN

Adhesives are crucial both in nature and in diversified artificial fields, and developing environment-friendly adhesives with economic procedures remains a great challenge. We report that folic acid-based coacervates can be a new category of excellent adhesives for all kinds of surfaces with long-lasting adhesiveness. Aided by the electrostatic interaction between the π-π stacked folic acid quartets and polycations, the resultant coacervates are able to interact with diversified substrates via a polyvalent hydrogen bond, coordination, and electrostatic interactions. The adhesivity to wood is superior to the strong commercial glues, but without releasing any toxic components. Upon evaporating water, the coacervate can be casted into a non-adhesive flexible self-supporting film, which restores the adhesive coacervate immediately on contacting water with original adhesive ability. In this way, the coacervate can be facilely tailored into a double-sided tape (DST), which is convenient for storage and application under ambient conditions. Given its excellent adhesive performance, release of nontoxic gases, and convenience in storage and application, the folic acid-based DST is very promising as a new adhesive material.

9.
Exp Ther Med ; 21(3): 241, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33603849

RESUMEN

Severe cholestatic liver injury diseases, such as obstructive jaundice and the subsequent acute obstructive cholangitis, are induced by biliary tract occlusion. Heat shock protein 90 (HSP90) inhibitors have been demonstrated to be protective for various organs. The potential of HSP90 inhibitors in the treatment of cholestatic liver injury, however, remains unclear. In the present study, rat models of bile duct ligation (BDL) were established, the HSP90 inhibitor 17-dimethylamino-ethylamino-17-demethoxygeldanamycin (17-DMAG) was administered, and its ability to ameliorate the cholestasis-induced liver injuries was evaluated. In the BDL rat models and clinical samples, increased HSP90 expression was observed to be associated with cholestatic liver injury. Furthermore, 17-DMAG alleviated cholestasis-induced liver injury in the rat models, as revealed by the assessment of pathological changes and liver function. In addition, 17-DMAG protected hepatocytes against cholestatic injury in vitro. Further assays indicated that 17-DMAG administration prevented cholestasis-induced liver injury in the rats by decreasing the expression of interleukin (IL)-1ß and IL-18. Moreover, 17-DMAG also decreased the cholestasis-induced upregulation of IL-1ß and IL-18 in liver sinusoidal endothelial cells in vitro. In conclusion, the HSP90 inhibitor 17-DMAG is able to prevent liver injury in rats with biliary obstruction, and this phenomenon is associated with the reduction of IL-1ß and IL-18 expression.

10.
Sci Rep ; 11(1): 4391, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33623100

RESUMEN

Gallbladder cancer is the most common malignant tumor of the biliary system and is characterized by difficulty to diagnose in early stages, a high degree of malignancy, and poor prognosis. Finding new drugs may improve the prognosis for this dismal cancer. Herein, we investigated the potential application of pterostilbene (PTS) against gallbladder cancer in vivo and in vitro. PTS potently inhibited cell proliferation, migration and invasion of gallbladder cancer cells. Moreover, PTS also had a function of inducing apoptosis in vitro. Meanwhile, PTS reversed EMT with a correlated inhibition of PI3K/Akt activation. Tumor xenograft models showed that PTS inhibited tumor growth and had low toxicity in vivo, which were consistent with the in vitro data. These findings indicate that PTS arrests cell growth through inhibition of PI3K/AKT signaling and is a potential drug for the therapy of gallbladder cancer.


Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Neoplasias de la Vesícula Biliar/tratamiento farmacológico , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Estilbenos/uso terapéutico , Animales , Antineoplásicos Fitogénicos/farmacología , Apoptosis , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Humanos , Masculino , Ratones , Ratones Desnudos , Transducción de Señal/efectos de los fármacos , Estilbenos/farmacología
11.
Biomed Res Int ; 2020: 3235786, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32923479

RESUMEN

ARAF is a member of the RAF kinase family that is necessary for mitogen-activated protein kinase (MAPK) activation in various malignancies, including lung, colorectal, pancreatic, and breast cancers. As the most common biliary tract tumor, gallbladder cancer (GBC) seriously harms human health while the function of ARAF in GBC remains elusive. Here, we found that ARAF expression was upregulated in gallbladder cancer tissues. In vitro, ARAF silencing mediated by RNA interference effectively inhibited cell proliferation, colony formation, migration, and invasion of GBC cells. Moreover, knocking down ARAF suppressed tumor growth in vivo. Our results indicated that ARAF functions as an oncogene in GBC and, thus, could be a potential therapeutic target for GBC.


Asunto(s)
Neoplasias de la Vesícula Biliar/genética , Quinasas raf/genética , Animales , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Femenino , Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/patología , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Sistema de Señalización de MAP Quinasas/genética , Masculino , Ratones , Ratones Desnudos , Fenotipo , Regulación hacia Arriba/genética
12.
Angew Chem Int Ed Engl ; 59(25): 10081-10086, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-31633871

RESUMEN

Hydration water greatly impacts the color of inorganic crystals, but it is still unknown whether hydration water can be utilized to systematically manipulate the emission color of organic luminescent groups. Now, metal ions with different hydration ability allow fine-tuning the emission color of a fluorescent group displaying aggregation induced emission (AIE). Because the hydration water can be removed easily by gentle heating or mechanical grinding and re-gained by solvent fuming, rewritable materials can be fabricated both in the hot-writing and cold-writing modes. This hydration-facilitated strategy will open up a new vista in fine-tuning the emission color of AIE molecules based on one synthesis and in the design of smart luminescent devices.

13.
Mol Med Rep ; 19(6): 5177-5184, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31059036

RESUMEN

Gap junctions (GJs) and tight junctions (TJs) are essential to maintain the function of hepatocytes. Changes in biliary tract pressure and the effect of lipopolysaccharide (LPS) may lead to acute obstructive cholangitis (AOC) and cause liver injury via GJ and TJ dysfunction. Hydrogen has been confirmed to have a protective role in various organs during pathological conditions and inflammation. The present study investigated the function of junction proteins and the potential application of H2 in AOC­induced liver injury. An AOC rat model was established by LPS injection through a bile duct catheter, while the distal bile duct was closed. The catheter sealing caps were removed and bile was allowed to flow out from the catheters at 12 h after LPS infusion. The potential application of H2 was studied in the AOC rat model with biliary drainage. It was observed that AOC induced the disruption of junction proteins of both GJs and TJs. H2 administration reversed AOC­induced disruption of GJs and TJs after biliary drainage. The mechanism of this phenomenon suggests that H2 may have effectively attenuated AOC­induced inflammatory and oxidative damage, and decreased matrix metalloproteinase activity. H2 may accelerate the reversal of AOC­induced liver dysfunction, and this phenomenon may depend on reversing the inhibition of GJs and TJs.


Asunto(s)
Colangitis/patología , Uniones Comunicantes/metabolismo , Hidrógeno/farmacología , Hepatopatías/etiología , Uniones Estrechas/metabolismo , Enfermedad Aguda , Alanina Transaminasa/metabolismo , Animales , Aspartato Aminotransferasas/metabolismo , Colangitis/complicaciones , Colangitis/tratamiento farmacológico , Conexinas/metabolismo , Modelos Animales de Enfermedad , Hidrógeno/química , Hidrógeno/uso terapéutico , Lipopolisacáridos/toxicidad , Hígado/metabolismo , Masculino , Metaloproteinasas de la Matriz/metabolismo , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Solución Salina/química , Proteína de la Zonula Occludens-1/metabolismo
14.
Chem Commun (Camb) ; 55(33): 4829-4832, 2019 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-30949634

RESUMEN

The fluorescence of a coordinative molecule DCM displaying an intramolecular charge transfer (ICT) effect is regulated by several metal ions. These DCM-metal complexes were adopted to recognize different chemicals, including the recognition of triethylenetetramine, thiol-containing amino acids, and H2S upon binding DCM with Zn2+, Ag+, and Pb2+, respectively. This is in analogy to the general mode of human trichromatic color vision.

15.
Comb Chem High Throughput Screen ; 22(4): 276-279, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30947661

RESUMEN

BACKGROUND: Intrahepatic Biliary Cystadenoma (IBC) is rare but has a high incidence of misdiagnosis, especially for experienceless surgeons. CASE: We report a case of IBC located in the caudate lobe and described a typical procedure of misdiagnosing this disease. Finally, the patient was successfully cured, but the procedure of misdiagnosis should attract attention. IBC and atypical biopsy for histological examination are the most important causes of misdiagnosis. Recurrent cystic lesions of the liver and repeated increases in CA 19-9 may suggest a "liver cyst", which is a misdiagnosis. CONCLUSION: The experience and lessons of misdiagnosis, in this case, may help other clinicians diagnose the rare disease accurately.


Asunto(s)
Neoplasias del Sistema Biliar/diagnóstico por imagen , Cistoadenoma/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Adulto , Neoplasias del Sistema Biliar/cirugía , Cistoadenoma/cirugía , Errores Diagnósticos , Femenino , Humanos , Neoplasias Hepáticas/cirugía , Tomografía Computarizada por Rayos X
17.
Langmuir ; 34(20): 5935-5942, 2018 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-29708341

RESUMEN

Allosteric regulation is extensively employed by nature to achieve functional control of protein or deoxyribonucleic acid through triggered conformational change at a remote site. We report that a similar strategy can be utilized in artificial self-assembly to control the self-assembled structure and its function. We show that on binding of metal ions to the headgroup of an amphiphile TTC4L, the conformational change may lead to change of the dipole orientation of the energy donor at the chain end. This on the one hand leads to a drastically different self-assembled structure; on the other hand, it enables light harvesting between the donor-acceptor. Because the Forster resonance fluorescence transfer efficiency is gated by metal ions, controlling the feeding of metal ions allows switching on and off of light harvesting. We expect that using allosteric self-assembly, we will be able to create abundant structures with distinct function from limited molecules, which show prominent potential for the postorganic modification of the structure and function of self-assembled materials.

18.
Chem Commun (Camb) ; 54(47): 5960-5963, 2018 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-29736502

RESUMEN

Carbon dots (CDs) with an absolute fluorescence quantum yield of 87% are facilely prepared via irradiation of self-assembled terthiophene amphiphile TTC4L in aqueous solution by mild visible light. Visible light irradiation of TTC4L triggers the production of superoxide radicals in water, which oxidize the closely packed terthiophene group into carbon dots. Our results reveal that the molecular self-assembly may act as important precursor for the generation of single molecule-like carbon dots; this method paves the way for the fabrication of CDs of high quality.

19.
Oncol Lett ; 15(3): 3305-3312, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29435072

RESUMEN

Resistance to chemotherapy is associated with dismal prognosis in patients with gallbladder cancer. Cyclin-dependent kinase 10 (CDK10) influences the chemosensitivity of gallbladder cancer cells, and cyclin M is the activating factor and binding partner of CDK10. To determine the effect of CDK10 or cyclin M overexpression on chemosensitivity, gemcitabine-resistant (GR) subclones were established from CDK10 or cyclin M stable transfectants. Stable overexpression of CDK10 increased the sensitivity to gemcitabine in non-resistant cells and did not further increase the sensitivity to gemcitabine in the GR subclones. GR subclones exhibited a significantly decreased expression of cyclin M while maintaining the expression levels of CDK10, compared with the non-resistant cells. MicroRNA (miR)-433 was identified as a candidate factor involved in the mechanism of the downregulation of M cyclin in GR subclones. Luciferase assays confirmed the interaction between miR-433 and the 3' untranslated region (3'UTR) of cyclin M. Additionally, ectopic expression of miR-433 significantly decreased the expression of cyclin M. Finally, increased expression of circulating miR-433 was associated with poor outcome of chemotherapy. The results of the present study suggest that miR-433 is a potential biomarker for evaluating chemosensitivity in gallbladder cancer.

20.
Oncol Lett ; 14(1): 89-96, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28693139

RESUMEN

Tumor angiogenesis is essential during lung cancer development and targeting angiogenesis may possess a potential therapeutic value. The present study demonstrates that azithromycin, a Food and Drug Administration-approved antibiotic drug, is a novel tumor angiogenesis inhibitor. Azithromycin inhibits capillary network formation of human lung tumor associated-endothelial cells (HLT-ECs) in vitro and in vivo. It significantly inhibits HLT-EC adhesion and vascular endothelial growth factor (VEGF)-induced proliferation of HLT-ECs in a dose-dependent manner without affecting migration. In addition, azithromycin induces apoptosis of HLT-ECs even in the presence of VEGF. Notably, azithromycin inhibits proliferation and induces apoptosis in multiple lung cancer cell lines to a significantly reduced extent compared with in HLT-ECs, suggesting that HLT-ECs are more susceptible to azithromycin treatment. In a lung tumor xenograft model, azithromycin significantly inhibits tumor growth and its anti-tumor activities are achieved by suppressing angiogenesis. Notably, the inhibitory effects of azithromycin on angiogenesis are associated with its ability to suppress VEGF-induced activation of VEGF receptor 2 (VEGFR2), phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt), focal adhesion kinase, and disruption of focal adhesion assembly and actin stress fiber formation in HLT-ECs. The present study identifies that azithromycin targets VEGFR2-mediated focal adhesion and PI3K/Akt signaling pathways in HLT-ECs, leading to the suppression of angiogenesis and lung tumor growth.

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