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1.
Sci Total Environ ; 696: 133883, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31446287

RESUMO

As a promising thermally driven separation process, membrane distillation (MD) is capable of treating challenging wastewaters. However, the traditional hydrophobic membranes are vulnerable to fouling by non-polar contaminants owing to the strong hydrophobic-hydrophobic interactions. To address this problem, we developed novel anti-oil-fouling MD membranes in this study. The composite membranes with asymmetric wettability were fabricated through electrospinning polyacrylonitrile (PAN) fibrous coating on a hydrophobic polytetrafluoroethylene (PTFE) membrane, followed by hydrolyzing the PAN coating with ethylenediamine (EDA) and NaOH, respectively. These two composite membranes exhibited excellent underwater superoleophobicity, with the underwater oil contact angle >150°, which can be attributed to the fibrous and re-entrant surface structure and the optimized surface hydrophilicity of the electrospun coating. During MD process using saline and oily emulsion as feed, the composite membranes presented robust anti-oil-fouling performance, indicating by stable permeate flux and salt rejection. A novel oil-droplet adhesion force probe was introduced to quasi-quantitatively elucidate oil-membrane interaction and evaluate membrane fouling propensity, the force spectroscopy indicated that the fabricated composite membranes had fairly less attractive to crude oil compared with the PTFE membrane. Our research results suggest that the novel composite membranes with asymmetric wettability were competent to serve as an anti-oil-fouling MD membrane for desalinating challenging saline and oily wastewaters.

2.
J Biomed Nanotechnol ; 15(9): 1867-1880, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31387675

RESUMO

The present study aims to evaluate the effect of the ethyl acetate extract of Cichorium (EAEC) as a novel photosensitizer in photodynamic therapy (PDT) of colorectal carcinoma (CRC) HCT116 and SW620 cells. The absorption and fluorescence spectra of EAEC were measured using a UV-vis spectrophotometer and fluorescence spectrophotometer, respectively. EAEC-induced reactive oxygen species (ROS) production in HCT116 and SW620 cells was detected using 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) and glutathione/glutathione disulfide (GSH/GSSG). The photo- and dark toxicities of EAEC were estimated using the Cell Counting Kit-8 (CCK-8) assay. Cellular uptake and localization of EAEC were detected by confocal laser fluorescence microscopy. Annexin V-FITC/PI staining, Western blotting and immunofluorescence staining were used to assess apoptosis and autophagy. The antitumor activity of EAEC was confirmed in a xenograft model. Finally, effects on the PERK pathway were verified using qRT-PCR and Western blotting. EAEC displayed absorption and fluorescence emission peaks at 660 nm and 678 nm, respectively. EAEC induced ROS production in CRC cells. Assessment of dark toxicity showed that treatment with EAEC alone induced little cytotoxicity in CRC or normal cells but that EAEC-PDT induced significant photocytotoxicity in CRC cells in a time- and dose-dependent manner. After cellular uptake, EAEC was located in the mitochondria. Treatment with EAEC-PDT reduced xenograft tumor size. Further evaluation suggested that activation of the PERK pathway mediates these effects, as the apoptotic rate and autophagy flux increased markedly after EAEC-PDT. EAEC, a natural photosensitizer extracted from Cichorium, displays potential utility in PDT of CRC by targeting the PERK pathway.


Assuntos
Autofagia , Neoplasias Colorretais , Fotoquimioterapia , Acetatos , Apoptose , Linhagem Celular , Linhagem Celular Tumoral , Estresse do Retículo Endoplasmático , Humanos , Fármacos Fotossensibilizantes , Proteínas Quinases , Espécies Reativas de Oxigênio
3.
Inorg Chem ; 58(12): 7947-7957, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31185555

RESUMO

The mixed hexa-transition metal (hexa-TM) sandwiched arsenotungstate derivative, [CuI3(pz)2(phen)3]2[CuI(phen)2][{Na(H2O)2}{(VIV5CuIIO6)(AsIIIW9O33)2}]·6H2O (1) (pz = pyrazine; phen = 1,10-phenanthroline), has been hydrothermally synthesized and structurally characterized. In compound 1, two {AsW9O33} clusters are connected by mixed hexa-TM ring unit {VVI5CuIIO6} to form a sandwich-type dimer, which are further bonded in "ABAB" mode by the {Na(H2O)2} linker resulting in pure inorganic chains. The unique "L-shaped" trinuclear complex {Cu3(phen)3(pz)2} is supported together via staggered π-π interactions to generate extending waveform two-dimensional supramolecular layers, which are further aggregated with their adjacent analogues by complexes {Cu(phen)2} via H-bonding interaction to yield an unprecedented three-dimensional (3D) metal-organic networks with one-dimensional (1D) cavities. The pure inorganic 1D sandwich chains are implanted in the cavities as guest units via supramolecular interactions to form a POMOF 3D framework. Compound 1, as the electrode of the supercapacitor, exhibits higher specific capacitances (825 F g-1 at a current density of 2.4 A g-1), better rate capability, more durable cyclic stability (91.4% of cycle efficiency after 3000 cycles), and improved conductivity and electroactivity compared to those of parent polyoxometalate (POM) Na9[AsW9O33]·19H2O (2) and 6-Cu-substituted POM [Cu6(imi)6{AsIIIW9O30Cl3}2]·6H2O (3), which may be attributed to the introduction of V4+, the unique host-guest structure, and the rich π electron system. In addition, compound 1 exhibits dual-function electrocatalytic behavior in reducing inorganic salt IO3- and oxidizing the organic molecule dopamine.

4.
Dig Liver Dis ; 51(10): 1446-1455, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31147216

RESUMO

BACKGROUND: Emerging data suggest the crucial regulatory roles of circular RNAs (circRNAs) in hepatocellular carcinoma (HCC). However, the pathophysiology role of circZFR in HCC remains largely unknown. AIMS: This study aims to disclose the functions of circZFR in HCC progression and its potential molecular mechanism. METHODS: circZFR and miR-511 were identified by qRT-PCR. Colony formation assay, wound-healing assay, transwell assay, and flow cytometry assay were performed to determine the cell proliferation, migration, invasion and apoptosis. Western blotting and immunohistochemistry (IHC) were utilized to evaluate the expression level of AKT1, GSK3ß, ß-catenin and cascades of proliferation-related proteins both in vitro and in vivo. Dual luciferase reporter assay was conducted to evaluate the interactions among circZFR, miR-511 and AKT1. RESULTS: The expression of circZFR was enhanced and the expression of miR-511 was down-regulated in HCC tissues and cells. Functionally, circZFR silencing or miR-511 overexpression suppressed cell proliferation, migration and invasion, and induced apoptosis of HCC cells. Mechanistically, circZFR acted as a miR-511 sponge to up-regulate its target gene AKT1, which activated cascades of proliferation-related proteins (c-Myc, cyclin D1, Survivin and Bcl-2). Furthermore, depletion of circZFR inhibited tumorigenesis and decreased the expression level of AKT1 in xenograft models. CONCLUSION: circZFR promotes HCC progression by directly down-regulating miR-511 to activate AKT1 signaling, suggesting that circZFR is a potential target in HCC treatment. Targeting circZFR may provide therapeutic benefits for HCC.

5.
ACS Appl Mater Interfaces ; 11(22): 20249-20256, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-31083968

RESUMO

It was previously proved that the existence of a large amount of hydrogen ions in water-based lubricants can easily lead to a superlubric state; however, it was also shown that these hydrogen ions could cause severe corrosion. As part of a large family of attractive clays, layered double hydroxides (LDHs) possess excellent tribological properties in water-based lubrication systems. In the present work, two different kinds of LDHs are dispersed in polyalkylene glycol (PAG) aqueous solutions, in two distinct forms: ultrathin nanosheets (ULDH-NS) of ca. 60 nm wide and ca. 1 nm thick (single or double layer) and nanoparticles (LDH-NP) of ca. 19.73 nm wide and ca. 8.68 nm thick. We find that the addition of ULDH-NS greatly shortens (as much as 85%) the running-in period prior to reaching the superlubricity regime and increases the ultimate load-bearing capacity by about four times. As compared to the fluid film thickness of the lubricating PAG solution, their ultrathin longitudinal dimension will not impair or influence the fluid film coverage in the contact zone. The analysis of sliding solid surfaces and the atomic force microscope microscale friction test demonstrate that the adsorption of ULDH-NS enables the sliding solid surfaces to be polished and protected because of their relatively weak interlayer interaction and increased adhesion effect. Owing to their superior tribological properties as lubricant additives, ultrathin LDH nanosheets hold great potential for enabling liquid superlubricity in industrial applications in the future.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 218: 206-212, 2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-30995578

RESUMO

Hydrogen sulfide (H2S) is a kind of gaseous signal molecule in many physiological processes. In order to detect H2S, a novel "turn on" fluorescent probe 6,12-dihydroxyperylene-1,7-dione (DPD) was designed and synthesized. The probe DPD is fluorescence silence, while the addition of H2S induces an obvious green fluorescence with an obvious color change from dark blue to yellow-green. The probe shows excellent selectivity, fast response (2.5min) and linear curve (0-90µM) in wide effective pH range (4-10). Competition experiments are also revealed in corresponding studies and the detection limit is 3.6µM. The response mechanism is proved to be the reduction of the probe by H2S, which is confirmed by 1H NMR. Furthermore, through the fluorescence turn-on signal toward H2S in Hela cells, probe DPD was successfully applied to monitor H2S in living Hela cells.


Assuntos
Corantes Fluorescentes/química , Sulfeto de Hidrogênio/análise , Perileno/análogos & derivados , Quinonas/química , Fluorescência , Corantes Fluorescentes/síntese química , Células HeLa , Humanos , Limite de Detecção , Microscopia Confocal , Imagem Óptica , Perileno/síntese química , Perileno/química , Quinonas/síntese química , Espectrometria de Fluorescência
7.
Sci Rep ; 9(1): 3475, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30837547

RESUMO

Metasurface, fluorescent microscopy and scanning near-field optical microscopy can improve the resolution of microscopes remarkably, while the resolution of the telescope remains unimproved constrained by its giant objective lenses and distant targets. Here we put forward a way to raise the resolution of telescopes simply by adding a binary optical thin surface around its focal plane. Simulation results show that the surface can raise the image quality in the Cassegrain and Kepler telescope. By nano-lathe, we fabricated a designed binary surface and experiment it in the Kepler telescope. The results are consistent with those of simulation results. More details of the calibrated target are resolvable on the image plane after applying the binary optical surface. It proves that the binary optic surface can make contribute to the resolution of the telescope, thus is beneficial in astronomy, military surveillance field.

8.
Med Sci Monit ; 25: 1952-1959, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30873956

RESUMO

BACKGROUND MicroRNAs (miRNAs) have emerged as central regulators of many processes. MiRNA-34 (miR-34) functions as a well-known tumor suppressor. The aim of this study was to investigate the mechanisms underlying how miR-34 participates in vascular disorders. MATERIAL AND METHODS Three miR-34 family members (miR-34a, miR-34b, and miR-34c) were overexpressed or silenced in human vascular smooth muscle cells (VSMCs) and umbilical vein endothelial cells (UVECs), respectively, before the proliferation and apoptosis of cells were detected by using Cell Counting Kit-8 assay and Annexin V- fluorescein isothiocyanate/propidium iodide flow cytometry. The protein expression of apoptosis biomarkers was detected by western blot. Dual-luciferase reporter assay was performed to determine the candidate target of miR-34, and enzyme-linked immune sorbent assay was used to evaluate the effect of miR-34 on the expression of the target gene. RESULTS Overexpression of miR-34 family members repressed proliferation and promoted apoptosis of VSMCs and UVECs, whereas miR-34 knockdown led to the opposite results. In addition, miR-34a inhibited the expression of alpha-1 antitrypsin (AAT), a serine protease inhibitor that suppresses the degradation of extracellular matrix, through a miR-34-binding site within the 3'-UTR of AAT. CONCLUSIONS MiR-34 promoted apoptosis of VSMC and UVEC cells by inhibiting AAT expression. This finding provides an update on the understanding of the clinical value of miR-34, which might assist to uncover novel and effective therapeutic strategies for the treatment of vascular diseases.


Assuntos
MicroRNAs/genética , MicroRNAs/fisiologia , Doenças Vasculares/genética , Regiões 3' não Traduzidas/genética , Apoptose/genética , Movimento Celular/genética , Proliferação de Células/genética , China , Matriz Extracelular/genética , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiologia , Neoplasias/genética
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 214: 487-495, 2019 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-30818149

RESUMO

In this work, we have designed and synthesized a dinitrobenzene-sulfonate tetrahydro[5]helicene (H-DNP) as an effective fluorescent probe for detection of hydrogen sulfide (H2S). Upon the addition of H2S, a significant fluorescence enhancement (75-fold) at 495 nm can be observed with a distinct color change from colorless to yellow. Additionally, H-DNP shows low background spectroscopic signal, large Stokes Shift up to ~140 nm, good sensitivity, rapid response time less than 2 min, low detection limit (48 nM) and high selectivity toward common bio-thiols (Cysteine, Homocysteine and Glutathione). Compared with the previous dinitrophenoxy tetrahydro[5]helicene, this probe has shorter response time and lower detection limit. Most importantly, this probe H-DNP has low toxicity to cells and excellent cell permeability, which can be applied to visualize H2S in living cells.


Assuntos
Corantes Fluorescentes , Sulfeto de Hidrogênio/metabolismo , Compostos Policíclicos , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Células HeLa , Humanos , Limite de Detecção , Microscopia de Fluorescência , Compostos Policíclicos/síntese química , Compostos Policíclicos/química , Compostos Policíclicos/farmacologia
10.
Chem Asian J ; 14(9): 1462-1466, 2019 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-30883030

RESUMO

A general and efficient synthetic methodology for the preparation of enantio- and diastereopure [6]-, and [7]helicenes is developed. Commercially available chiral binaphthanols are utilized to generate the arylene-vinylene precursors, which undergo helical folding via photocyclization to give enantio- and diastereopure [6]-, and [7]helicenes. These optically pure helicenes could be easily obtained via silica gel column chromatography without the use of expensive HPLC or chiral resolution reagents. The configurations and structures of these helicenes are confirmed by CD spectra and X-ray crystallographic analysis. This work provides a new method for preparation of enantiopure helicenes.

11.
Talanta ; 196: 243-248, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30683359

RESUMO

In this study, a new coumarin-based fluorescent and chromogenic dual channel probe (DC) was used for the selective detection of homocysteine (Hcy) over other amino acids, especially for cysteine (Cys) and glutathione (GSH). When Hcy is present in the solution, the remarkable fluorescence enhancement and obvious blue shift in UV-vis spectra can be observed. In addition, the color change from purple to yellow can be observed clearly by unaided eyes. This probe DC has fast response time, excellent sensitivity and selectivity to Hcy. A linear relationship exists between the ratio of emissions at 486 and 625 nm, and Hcy can be detected in a wide concentration range (0-200 µM). The signal-to-background ratio of fluorescence at 486 nm can reach 8.4, and the detection limit is calculated to be 3.5 µM. The response mechanism is proved to be the Michael addition reaction by Hcy. Preliminary results on cell imaging enable the practical application of Hcy tracing in living cells.

12.
Nat Methods ; 15(12): 1083-1089, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30504871

RESUMO

Single-particle electron cryomicroscopy (cryo-EM) involves estimating a set of parameters for each particle image and reconstructing a 3D density map; robust algorithms with accurate parameter estimation are essential for high resolution and automation. We introduce a particle-filter algorithm for cryo-EM, which provides high-dimensional parameter estimation through a posterior probability density function (PDF) of the parameters given in the model and the experimental image. The framework uses a set of random support points to represent such a PDF and assigns weighting coefficients not only among the parameters of each particle but also among different particles. We implemented the algorithm in a new program named THUNDER, which features self-adaptive parameter adjustment, tolerance to bad particles, and per-particle defocus refinement. We tested the algorithm by using cryo-EM datasets for the cyclic-nucleotide-gated (CNG) channel, the proteasome, ß-galactosidase, and an influenza hemagglutinin (HA) trimer, and observed substantial improvement in resolution.

13.
Scand J Gastroenterol ; 53(12): 1562-1568, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30572742

RESUMO

BACKGROUND AND AIMS: The impact of portal hypertension (PH) on postoperative short-term outcomes and long-term survival in hepatocellular carcinoma (HCC) patients has lately been discussed controversially. This study aimed to explore the influence of PH on postoperative outcomes in HCC patients undergoing surgical resection. METHODS: Patients undergoing hepatectomy for HCC from 2010 to 2014 were enrolled. The impact of PH on postoperative complications, posthepatectomy liver failure (PHLF) and overall survival (OS) was evaluated. RESULTS: A total of 355 HCC patients were enrolled; 129 (36.3%) experienced postoperative complications and 21 (5.9%) developed PHLF. PH was identified as an independent predictor of PHLF. Patients with PH experienced a higher incidence of complications and PHLF than patients without PH. On the Cox proportional hazards regression model, PH was verified as a risk factor of OS for BCLC stage 0/A and B patients. Patients without PH had significantly better long-term survival compared to patients with PH both in the total cohort and in cirrhosis subgroup. CONCLUSION: Liver resection in HCC patients with PH showed a significantly increased postoperative complications and PHLF, and revealed a decreasing long-term survival than non-PH patients. Besides, tumor burden also played an important role in determining the OS. However, due to the improvement in surgical technique and perioperative management, surgery was feasible in carefully selected HCC patients with PH.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hipertensão Portal/complicações , Falência Hepática/epidemiologia , Neoplasias Hepáticas/cirurgia , Complicações Pós-Operatórias/epidemiologia , Adulto , Carcinoma Hepatocelular/mortalidade , China/epidemiologia , Feminino , Hepatectomia , Mortalidade Hospitalar , Humanos , Incidência , Cirrose Hepática/complicações , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida
14.
Photodiagnosis Photodyn Ther ; 24: 349-357, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30385297

RESUMO

BACKGROUND: Inflammatory bowel disease (IBD) is a group of inflammatory conditions characterized by chronic inflammation of the gastrointestinal (GI) tract. Recent preclinical and clinical studies have shown the therapeutic value of photodynamic therapy with low doses of photosensitizer and/or light in colitis treatment, but the detailed mechanism is unclear. METHODS: We examined 5-aminolevulinic acid (5-ALA) mediated photodynamic therapy (PDT) in dextran sulfate sodium (DSS)-induced colitis in mice. Endoscopic and macroscopic observations as well as the Disease Activity Index score (DAI) was used to monitor the disease. Cytokine expression was measured by quantitative RT-PCR analysis to evaluate the efficacy of PDT. We applied the Clariom™ D bioinformatics analysis to investigate the differentially expressed genes after PDT. Finally, we used quantitative RT-PCR analysis and Western blotting to validate the targets of differentially expressed genes. RESULTS: 5-ALA-PDT improved the DAI score and decreased the expression of various inflammatory cytokines. The Clariom™ D bioinformatics analysis identified 2043 diff ;erentially expressed genes (702 up-regulated and 1341 down-regulated). We confirmed the down-regulation of lncRNA-Neat1, lncRNA-Snhg5 and lncRNA-Gm9926 and the up-regulation of miRNA-204-5p, miRNA-218-5p, miRNA-200a-3p and miRNA-466h-5p. Additionally, the decreased expression level of the AKT3, p-AKT3, PI3K, p-PI3K protein were confirmed. CONCLUSIONS: This study provides in vivo comprehensive lncRNA and miRNA microarray analysis after 5-ALA-PDT treatment in DSS-induced colitis, and it may help to develop novel lncRNA-miRNA-related therapeutic approaches, such as the Neat1-miRNA204-5p-PI3K-AKT axis, to further increase the efficiency of PDT in IBD.

15.
J Colloid Interface Sci ; 537: 375-383, 2018 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-30465974

RESUMO

Membrane fouling caused by non-polar foulants is a challenging problem for hydrophobic membranes, which hinders the industrial implementation of membrane distillation (MD). The hydrophilic coating can create a hydration layer at solid-water interface, thereby the hydrophilic surfaces are expected to supply a barrier inhibiting adhesion of hydrophobic foulants. Hence, it should be possible to develop anti-fouling composite membranes through constructing a hydrophilic skin layer onto hydrophobic MD membranes. Herein, we fabricated a novel composite membrane for excellent anti-oil-fouling performance in MD process by electrospinning polyetherimide (PEI) nanofibers on the hydrophobic polyvinylidene fluoride (PVDF) membrane surface, followed by cross-linking with ethanediamine (EDA). The membrane morphology and structure properties, surface zeta potential and wettability, thermal stability were all systematically characterized, and force spectroscopy was used to quasi-quantitatively evaluate oil-membrane adhesion force. Compared with the PVDF membrane, the PVDF/PEI-EDA composite membrane exhibited strong resistance to crude oil with underwater oil contact angle of about 145° and low oil-membrane adhesion force, which contributed to the stable performance during MD desalinating an oily and saline solution. The fabricated composite membrane with underwater-oleophobic fibrous surface can effectively mitigate oil-fouling in MD and promote MD to treat highly saline wastewater with high concentration of hydrophobic foulants.

16.
Brief Bioinform ; 2018 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-30169568

RESUMO

Genetic risk score (GRS, also known as polygenic risk score) analysis is an increasingly popular method for exploring genetic architectures and relationships of complex diseases. However, complex diseases are usually measured by multiple correlated phenotypes. Analyzing each disease phenotype.

17.
Medicine (Baltimore) ; 97(34): e11994, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30142837

RESUMO

RATIONALE: Inflammatory myofibroblastic tumor (IMT) is uncommon, coexistence of IMTs in the kidney and abdominal wall are more uncommon. PATIENT CONCERNS AND DIAGNOSIS: We report a 74-year-old female who presented with 6 months history of left flank pain and approximately 5 kg weight loss that were diagnosed as renal cell carcinoma and locally metastatic abdominal wall tumor. INTERVENTIONS AND OUTCOMES: A left radical nephrectomy and excision of the abdominal wall tumor were done. The pathologic result was IMTs. After follow-up for 66 months, the patient showed no signs of tumor recurrence. LESSONS: Coexistence of IMTs in the kidney and abdominal wall is extremely rare and is often diagnosed as malignancy. Therefore, IMTs should be considered in the diagnosis of the patient with both kidney and abdominal wall tumors.


Assuntos
Neoplasias Abdominais/diagnóstico , Carcinoma de Células Renais/diagnóstico , Neoplasias Renais/diagnóstico , Miofibromatose/diagnóstico , Parede Abdominal/patologia , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Rim/patologia
18.
Spectrochim Acta A Mol Biomol Spectrosc ; 204: 295-300, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-29945112

RESUMO

Endogenous hydrogen sulfide plays an important role in various physiological and pathological processes and the convenient and selective recognition of hydrogen sulfide has become a research hotspot. We designed and synthesized a tetrahydro[5]helicene and 2,4-dinitrobenzene conjugate (HD-DNP) as an effective fluorescent probe for selective detection of H2S. The selective deprotection of 2,4-dinitrophenyl ether group of HD-DNP by H2S led to a dramatic fluorescent enhancement (101-fold) at 500 nm and colorimetric change in DMSO-PBS solution. HD-DNP displays many advantages including low background without any self-fluorescence, as well as high selectivity towards common bio-thiols such as Cysteine, Homocysteine and Glutathione. The detection limit of this probe for H2S was found to be about 2.4 µM with a wide linear range (10-70 µM). The response mechanism of the probe with HS- is confirmed to be thiolysis of the dinitrophenyl ether induced by HS- through 1H NMR comparison investigations.


Assuntos
Corantes Fluorescentes/química , Sulfeto de Hidrogênio/análise , Compostos Policíclicos/química , Dinitrobenzenos/química , Sulfeto de Hidrogênio/química , Limite de Detecção , Modelos Lineares
19.
Artigo em Inglês | MEDLINE | ID: mdl-29631251

RESUMO

Osteoarthritis (OA) is a degenerative synovial joint disease affecting people worldwide. However, the exact pathogenesis of OA remains unclear. Metabolomics analysis was performed to obtain insight into possible pathogenic mechanisms and diagnostic biomarkers of OA. Ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-TQ-MS), followed by multivariate statistical analysis, was used to determine the serum amino acid profiles of 32 OA patients and 35 healthy controls. Variable importance for project values and Student's t-test were used to determine the metabolic abnormalities in OA. Another 30 OA patients were used as independent samples to validate the alterations in amino acids. MetaboAnalyst was used to identify the key amino acid pathways and construct metabolic networks describing their relationships. A total of 25 amino acids and four biogenic amines were detected by UPLC-TQ-MS. Differences in amino acid profiles were found between the healthy controls and OA patients. Alanine, γ-aminobutyric acid and 4-hydroxy-l-proline were important biomarkers distinguishing OA patients from healthy controls. The metabolic pathways with the most significant effects were involved in metabolism of alanine, aspartate, glutamate, arginine and proline. The results of this study improve understanding of the amino acid metabolic abnormalities and pathogenic mechanisms of OA at the molecular level. The metabolic perturbations may be important for the diagnosis and prevention of OA.


Assuntos
Aminoácidos/sangue , Aminoácidos/metabolismo , Metabolômica/métodos , Osteoartrite/sangue , Osteoartrite/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Estudos de Coortes , Feminino , Humanos , Masculino , Espectrometria de Massas/métodos , Pessoa de Meia-Idade , Modelos Estatísticos , Osteoartrite/epidemiologia , Curva ROC
20.
Photodiagnosis Photodyn Ther ; 21: 396-403, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29355734

RESUMO

BACKGROUND: Photodynamic therapy (PDT) has been reported to be a promising therapy for colon cancer because of its substantial safety features and its ability to induce a systematic reaction rather than local effects on the focal lesion in the intestine. Autophagy and apoptosis play important roles in the response to PDT. However, the role of autophagy after PDT treatment has not yet been clarified. METHODS: In this study, we investigated the relationship between apoptosis and autophagy in porphyrin IX (PpIX)-mediated PDT (PpIX-PDT) in HCT116 colon cancer cells. PpIX-PDT decreased cell viability in a concentration- and light dose-dependent manner. RESULTS: PpIX-PDT results in nuclear condensation, increased the expression of Caspase-3, Bax, and PARP, and decreased expression of Bcl-2. PpIX-PDT also induces the double membrane autophagosome, up-regulates LC3B, Atg7, Beclin-1, and Bcl-2 expression and down-regulates P62 expression. Inhibition of autophagy using chloroquine (CQ) or Atg7 knockdown with a shRNA enhances apoptotic cell death. Based on these findings, autophagy plays a self-protective role in HCT116 cells in response to PpIX-PDT treatment. DISCUSSION: Both autophagy and apoptosis were induced by PpIX-PDT in HCT116 cells, and the inhibition of autophagy strengthened the proapoptotic effect of PpIX-PDT. Thus, the appropriate modulation of autophagy may be as a potential therapeutic target for colon cancer cells treated with PpIX-PDT.


Assuntos
Autofagia/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Protoporfirinas/farmacologia , Apoptose/efeitos dos fármacos , Proteína 7 Relacionada à Autofagia/biossíntese , Proteína Beclina-1/biossíntese , Caspase 3/metabolismo , Relação Dose-Resposta à Radiação , Regulação para Baixo , Células HCT116 , Humanos , Lasers Semicondutores/uso terapêutico , Proteínas Associadas aos Microtúbulos/biossíntese , Poli Adenosina Difosfato Ribose/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas de Ligação a RNA/biossíntese , Regulação para Cima , Proteína X Associada a bcl-2/biossíntese
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