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1.
Zhongguo Zhong Yao Za Zhi ; 49(1): 130-140, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38403346

RESUMO

This study induced biological stress in Sorbus pohuashanensis suspension cell(SPSC) with yeast extract(YE) as a bio-tic elicitor and isolated and identified secondary metabolites of triterpenoids produced under stress conditions. Twenty-six triterpenoids, including fifteen ursane-type triterpenoids(1-15), two 18,19-seco-ursane-type triterpenoids(16-17), four lupine-type triterpenoids(18-21), two cycloartane-type triterpenoids(22-23), and three squalene-type triterpenoids(24-26), were isolated and purified from the methanol extract of SPSC by chromatography on silica gel, MCI, Sephadex LH-20, and MPLC. Their structures were elucidated by spectroscopic analyses. All triterpenoids were isolated from SPSC for the first time and 22-O-acetyltripterygic acid A(1) was identified as a new compound. Selected compounds were evaluated for antifungal, antitumor, and anti-inflammatory activities, and compound 1 showed an inhibitory effect on NO production in LPS-induced RAW264.7 cells.


Assuntos
Triterpenos Pentacíclicos , Sorbus , Triterpenos , Animais , Camundongos , Sorbus/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/metabolismo , Células RAW 264.7 , Estrutura Molecular
2.
Environ Sci Technol ; 57(47): 18668-18679, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36730709

RESUMO

Hydroxyl radical production via catalytic activation of HOCl is a new type of Fenton-like process. However, metal-chlorocomplex formation under high chloride conditions could deactivate the catalyst and reduce the process efficiency. Herein, in situ electrogenerated HOCl was activated to •OH via a metal-free, B/N-codoped carbon nanofiber cathode for the first time to degrade contaminant under high chloride condition. The results show 98% degradation of rhodamine B (RhB) within 120 min (k = 0.036 min-1) under sulfate conditions, while complete degradation (k = 0.188 min-1) was obtained in only 30 min under chloride conditions. An enhanced degradation mechanism consists of an Adsorb & Shuttle process, wherein adsorption concentrates the pollutants at the cathode surface and they are subsequently oxidized by the large amount of •OH produced via activation of HOCl and H2O2 at the cathode. Density functional theory calculations verify the pyridinic N as the active site for the activation of HOCl and H2O2. The process efficiency was also evaluated by treating tetracycline and bisphenol A as well as high chloride-containing real secondary effluents from a pesticide manufacturing plant. High yields of •OH and HOCl allow continuous regeneration of the cathode for several cycles, limiting its fast deactivation, which is promising for real application.


Assuntos
Radical Hidroxila , Poluentes Químicos da Água , Radical Hidroxila/química , Cloretos , Peróxido de Hidrogênio/química , Oxirredução , Antibacterianos , Poluentes Químicos da Água/análise , Eletrodos
3.
Environ Res ; 223: 115409, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36746203

RESUMO

An important way to promote the environmental industry's goal of carbon reduction is to promote the recycling of resources. Membrane separation technology has unique advantages in resource recovery and advanced treatment of industrial wastewater. However, the great promise of traditional organic membrane is hampered by challenges associated with organic solvent tolerance, lack of oxidation resistance, and serious membrane fouling control. Moreover, the high concentrations of organic matter and inorganic salts in the membrane filtration concentrate also hinder the wider application of the membrane separation technology. The emerging cost-effective graphene oxide (GO)-based membrane with excellent resistance to organic solvents and oxidants, more hydrophilicity, lower membrane fouling, better separation performance has been expected to contribute more in industrial wastewater treatment. Herein, we provide comprehensive insights into the preparation and characteristic of GO membranes, as well as current research status and problems related to its future application in industrial wastewater treatment. Finally, concluding remarks and future perspectives have been deduced and recommended for the GO membrane separation technology application for industrial wastewater treatment, which leads to realizing sustainable wastewater recycling and a nearly "zero discharge" water treatment process.


Assuntos
Grafite , Purificação da Água , Águas Residuárias , Membranas Artificiais
4.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(3): 374-381, 2023 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-37106519

RESUMO

Objective To investigate the effect of human platelet-rich plasma-derived exosomes(PRP-exos)on the proliferation of Schwann cell(SC)cultured in vitro. Methods PRP-exos were extracted by polymerization-precipitation combined with ultracentrifugation.The morphology of PRP-exos was observed by transmission electron microscopy,and the concentration and particle size distribution of PRP-exos were determined by nanoparticle tracking analysis.Western blotting was employed to determine the expression of the marker proteins CD63,CD81,and CD9 on exosome surface and the platelet membrane glycoprotein CD41.The SCs of rats were isolated and cultured,and the expression of the SC marker S100ß was detected by immunofluorescence staining.The fluorescently labeled PRP-exos were co-cultured with SCs in vitro for observation of their interaction.EdU assay was employed to detect the effect of PRP-exos on SC proliferation,and CCK-8 assay to detect the effects of PRP-exos at different concentrations(0,10,20,40,80,and 160 µg/ml)on SC proliferation. Results The extracted PRP-exos appeared as uniform saucer-shaped vesicles with the average particle size of(122.8±38.7)nm and the concentration of 3.5×1012 particles/ml.CD63,CD81,CD9,and CD41 were highly expressed on PRP-exos surface(P<0.001,P=0.025,P=0.004,and P=0.032).The isolated SCs expressed S100ß,and PRP-exos could be taken up by SCs.PRP-exos of 40,80,and 160 µg/ml promoted the proliferation of SCs,and that of 40 µg/ml showed the best performance(all P<0.01). Conclusions High concentrations of PRP-exos can be extracted from PRP.PRP-exos can be taken up by SCs and promote the proliferation of SCs cultured in vitro.


Assuntos
Exossomos , Plasma Rico em Plaquetas , Humanos , Ratos , Animais , Exossomos/metabolismo , Células de Schwann , Técnicas de Cocultura , Proliferação de Células , Células Cultivadas
5.
Anal Chem ; 94(14): 5514-5520, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35360906

RESUMO

Hydrogen sulfide (H2S) is an important endogenous gas signal molecule in living system, which participates in a variety of physiological processes. Very recent evidence has accumulated to show that endogenous H2S is closely associated with various cancers and can be regarded as a biomarker of cancer. Herein, we have constructed a new near-infrared fluorescent probe (DCP-H2S) based on isophorone-xanthene dye for sensing hydrogen sulfide (H2S). The probe shows remarkable NIR turn-on signal at 770 nm with a large Stokes shift of 200 nm, together with high sensitivity (15-fold) and rapid detection ability for H2S (4 min). The probe also possesses excellent selectivity for H2S over various other analytes including biothiols containing sulfhydryl (-SH). Moreover, DCP-H2S has been successfully applied to visualize endogenous and exogenous H2S in living cells (293T, Caco-2 and CT-26 cells). In particular, the excellent ability of DCP-H2S to distinguish normal mice and tumor mice is shown, and it is expected to be a powerful tool for detection of H2S in cancer diagnosis.


Assuntos
Corantes Fluorescentes , Sulfeto de Hidrogênio , Animais , Células CACO-2 , Células HeLa , Humanos , Camundongos , Imagem Óptica
6.
Anal Chem ; 93(34): 11826-11835, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34461732

RESUMO

Cancer ranks as a leading cause of death in every country of the world. However, if they are discovered early, a lot of cancers can be prevented or cured. Discovering and monitoring cancer markers are the main methods for early diagnosis of cancer. To date, many fluorescent probes designed and used for early cancer diagnosis can only react with a single marker, which always causes insufficient accuracy in complex systems. Herein, a novel near-infrared (NIR) fluorescent probe (CyO-DNP) for the sequential detection of H2S and H+ is synthesized. In this probe, a heptamethine dye is selected as the fluorophore and a 2,4-dinitrophenyl (DNP) ether is chosen as recognition group. In the presence of H2S, CyO-DNP is transformed into CyO, which exhibits an intense fluorescence at 663 nm. Then, H+ induces the protonation of CyO to obtain CyOH, and the final fluorescence emission at 793 nm significantly enhances. Owing to the low cytotoxicity and the NIR fluorescence emission, CyO-DNP can sequentially monitor endogenous H2S and H+ in cancer cells and image exogenous and endogenous H2S and H+ in mice. It is worth mentioning that CyO-DNP can effectively avoid the false positive signal caused by the liver and kidney and discriminate normal mice and tumor mice accurately. For all we know, CyO-DNP is the first fluorescent probe for early accurate diagnosis of cancer by sequentially detecting H2S and H+.


Assuntos
Sulfeto de Hidrogênio , Neoplasias , Animais , Corantes Fluorescentes , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Microscopia de Fluorescência , Neoplasias/diagnóstico
7.
Anal Chem ; 93(4): 2510-2518, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33470106

RESUMO

Carbon monoxide (CO), as a crucial gasotransmitter, is endogenously produced by the degradation of heme and plays a critical role in regulating various physiological and pathophysiological processes such as oxidative stress. Thus, an effective fluorescent probe for investigating the relationships between CO and oxidative stress in vivo is necessary. In this paper, a ratiometric near-infrared (NIR) fluorescent probe (CP-CO) based on a coumarin-benzopyran fluorophore for imaging CO is developed. CP-CO itself displays strong coumarin emission due to its spironolactone structure. After the probe is reacted with CO and PdCl2, a notable enhancement of emission intensity at 690 nm can be found, which results in an obvious red shift of emission (200 nm). Moreover, CP-CO exhibits high sensitivity toward CO and produces a high enhancement ratio (203-fold). In addition, the probe is applied for ratiometric monitoring of exogenous and endogenous CO levels in HepG2 cells. Furthermore, the fluorescence imaging of CP-CO in zebrafish is performed by two-photon excitation along with excellent penetration ability. Most importantly, CP-CO can visualize the upregulation of CO under lipopolysaccharide (LPS)-induced oxidative stress in a zebrafish model, which vividly reveals its excellent ability in the elucidation of CO function in related biological events.


Assuntos
Monóxido de Carbono/química , Corantes Fluorescentes , Monitorização Fisiológica/métodos , Estresse Oxidativo/fisiologia , Animais , Monóxido de Carbono/metabolismo , Células Hep G2 , Humanos , Raios Infravermelhos , Peixe-Zebra
8.
Anal Chem ; 93(6): 3301-3307, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33535747

RESUMO

Diabetes is one of the metabolic diseases marked by hyperglycemia and is often accompanied by the occurrence of some complications. As a biomarker of oxidative stress, hydrogen peroxide (H2O2) has close association with the occurrence and development of diabetes and its complications. Unfortunately, there is no fluorescent probe reported for imaging H2O2 in diabetic mice. Here, a novel near-infrared (NIR) fluorescent probe named QX-B was designed and synthesized to detect H2O2. For the probe, the quinolinium-xanthene dye is used as the fluorophore and borate ester is chosen as the response group. After the addition of H2O2, a strong NIR fluorescence signal at 772 nm is observed. The probe not only shows high sensitivity with 10-fold enhancement but also displays excellent selectivity to H2O2 over other possible interfering species. In the meantime, the possible response mechanism of QX-B toward H2O2 was proposed and verified by the high-performance liquid chromatography (HPLC) experiment, mass spectra (MS) experiment, and density functional theory (DFT) calculation. Furthermore, based on the low cell cytotoxicity of QX-B, it has been applied in imaging exogenous and endogenous H2O2 in HeLa cells, HCT116 cells, 4T1 cells, and zebrafish successfully. More importantly, inspired by the performance of NIR fluorescence, QX-B has been used in monitoring H2O2 in diabetic mice for the first time. This provides very important information for the diagnosis and treatment of diabetes and its complications.


Assuntos
Diabetes Mellitus Experimental , Corantes Fluorescentes , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Células HeLa , Humanos , Peróxido de Hidrogênio , Camundongos , Peixe-Zebra
9.
Analyst ; 146(1): 118-123, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33089835

RESUMO

As a kind of toxic gas, carbon monoxide (CO) can hinder uptake of oxygen in humans. However, more and more studies have shown that CO is an important gaseous messenger in the body and playing an indispensable role in intracellular signaling pathways. So, it is necessary to develop an analytical method to study CO in living organisms. Although there are many CO-responsive probes, most of them have the disadvantages of a small Stokes shift or short emission wavelength. In order to address the above issue, a novel probe (FDX-CO) with a large Stokes shift (190 nm) and long emission wavelength (770 nm) was firstly synthesized to detect CO. The probe shows high sensitivity and superior selectivity toward CO. Moreover, the probe was successfully used for visualizing exogenous and endogenous CO in cells by fluorescence imaging, 3D quantification analysis and flow cytometric analysis. More importantly, FDX-CO could excellently detect CO in mice, which suggests that this probe has the potential ability to image CO in vivo. This probe can be viewed as a useful tool in the research of CO.


Assuntos
Monóxido de Carbono , Corantes Fluorescentes , Animais , Células HeLa , Humanos , Camundongos , Imagem Óptica
10.
Korean J Parasitol ; 59(4): 377-392, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34470089

RESUMO

This paper is to illustrate the infestation and related ecological characteristics of chigger mites on the Asian house rat (Rattus tanezumi). A total of 17,221 chigger mites were collected from 2,761 R. tanezumi rats, and then identified as 131 species and 19 genera in 2 families. Leptotrombidium deliense, the most powerful vector of scrub typhus in China, was the first major dominant species on R. tanezumi. All the dominant mite species were of an aggregated distribution among different individuals of R. tanezumi. The species composition and infestations of chiggers on R. tanezumi varied along different geographical regions, habitats and altitudes. The species-abundance distribution of the chigger mite community was successfully fitted and the theoretical curve equation was S (R)=37e-(0.28R)2. The total chigger species on R. tanezumi were estimated to be 199 species or 234 species, and this further suggested that R. tanezumi has a great potential to harbor abundant species of chigger mites. The results of the species-plot relationship indicated that the chigger mite community on R. tanezumi in Yunnan was an uneven community with very high heterogeneity. Wide geographical regions with large host samples are recommended in the investigations of chigger mites.


Assuntos
Infestações por Ácaros , Tifo por Ácaros , Trombiculidae , Animais , China , Ecossistema , Infestações por Ácaros/veterinária , Ratos
11.
Anal Chem ; 92(6): 4244-4250, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32066231

RESUMO

Liver fibrosis is a major stage in the development of liver disease, and it is important to investigate its pathogenesis for early intervention or even reversal. Recent studies have found that intestinal disease can aggravate liver fibrosis through the role of the "gut-liver axis". Hypoxia is considered to be a typical characteristic of many diseases including ulcerative colitis and liver fibrosis. However, there is no fluorescent probe for hypoxia detection to investigate the "gut-liver axis". Herein we design and synthesize a turn-on fluorescent probe termed Cy-AP, which displays high sensitivity and selectivity to hypoxia given by sodium dithionite (Na2S2O4) in vitro with near-infrared (NIR) emission (725 nm). The possible response mechanism of Cy-AP toward hypoxia is given and proved though HPLC, MS, and theory calculation. Moreover, on the basis of low cell cytotoxicity, the probe is used in visualizing hypoxia in four cell lines (HepG2, HCT116, HeLa, and MCF-7 cells) by fluorescence imaging, flow cytometry, and 3D imaging. Furthermore, due to its NIR emission, Cy-AP can monitor the hypoxia condition in vivo such as in liver fibrosis mice and ulcerative colitis mice models. In particular, the probe can validate the existence and mechanism of the "gut-liver axis" in vivo by monitoring hypoxia. To the best of our knowledge, this is the first work to give a strategy for studying the "gut-liver axis" by a NIR hypoxia-sensitive fluorescent probe, which will provide some powerful support for delaying the progression of liver fibrosis and thus promoting the treatment of liver disease.


Assuntos
Corantes Fluorescentes/química , Hipóxia/diagnóstico por imagem , Imagem Óptica , Animais , Corantes Fluorescentes/síntese química , Células HCT116 , Células HeLa , Células Hep G2 , Humanos , Raios Infravermelhos , Células MCF-7 , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , Estrutura Molecular , Neoplasias Experimentais/diagnóstico por imagem
12.
Mar Drugs ; 18(10)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32993037

RESUMO

Chemical investigation on a marine sponge, Dactylospongia elegans, yielded five new γ-oxygenated butenolide sesterterpene derivatives, dactylospenes A-E (1-5), as well as two known biosynthetically related compounds, luffariellolide (6) and furospinosulin B (7). The structures of these compounds were elucidated on the basis of their spectroscopic data, experimental and calculated electronic circular dichroism (ECD) analysis, as well as comparison of the NMR data with those of known analogs. These metabolites are the first γ-oxygenated butenolide sesterterpenes to be reported from this genus. These compounds were evaluated in antimicrobial, anti-inflammatory, and cytotoxic assays. Only compounds 1, 3, and 6 exhibited moderate cytotoxicity against DU145, SW1990, Huh7, and PANC-1 cancer cell lines with IC50 values in the range of 2.11-13.35 µM. Furthermore, compound 2, without cytotoxicity, exhibited significant inhibitory effects (inhibitory rate 77.5%) on nitric oxide production induced by lipopolysaccharide at 10 µM.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Antineoplásicos/isolamento & purificação , Poríferos/metabolismo , Sesterterpenos/isolamento & purificação , Animais , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Humanos , Lipopolissacarídeos , Camundongos , Óxido Nítrico/metabolismo , Células RAW 264.7 , Sesterterpenos/química , Sesterterpenos/farmacologia , Terpenos/isolamento & purificação
13.
Anal Chem ; 91(16): 10901-10907, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31362489

RESUMO

Azoreductase (AzoR) is an essential reductive enzyme which is closely associated with the intestinal disease such as ulcerative colitis (UC). To date, only a few fluorescent probes for detecting AzoR activity in bacteria or cells have been constructed successfully. It is still challenging to design fluorescent probes for in situ monitoring AzoR in vivo. In this paper, a near-infrared (NIR) fluorescent probe (Cy-Azo) based on hemicyanine is designed and synthesized. The emission of the probe is located at 735 nm in the NIR region, which is favorable for its application in vivo. In addition, Cy-Azo shows high sensitivity to AzoR activity with 17-fold fluorescence enhancement and is particularly selective to AzoR over other enzymes, ions, and amino acids. Meanwhile, a possible response mechanism (the azo group in Cy-Azo is reduced by AzoR and cleaved resulting in the production of Cy-NH2) was proposed and verified by HPLC, MS, and theory calculation. In addition, based on low cell cytotoxicity, Cy-Azo is successfully applied in visualizing the activity of AzoR in two cell lines (HCT116 and HepG2 cells) and three types of bacteria (E. coli, S. aureus, and P. aeruginosa). In particular, due to its NIR emission, the probe can monitor AzoR activity in acute and chronic UC mice models. To our knowledge this is the first fluorescent probe for detecting AzoR activity in vivo, which can provide much important information for the diagnosis and treatment of UC.


Assuntos
Colite Ulcerativa/diagnóstico por imagem , Corantes Fluorescentes/química , NADH NADPH Oxirredutases/análise , Imagem Óptica , Animais , Escherichia coli/isolamento & purificação , Células HCT116 , Células Hep G2 , Humanos , Raios Infravermelhos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência , NADH NADPH Oxirredutases/metabolismo , Nitrorredutases , Pseudomonas aeruginosa/isolamento & purificação , Staphylococcus aureus/isolamento & purificação
14.
Anal Chem ; 91(1): 1056-1063, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30539637

RESUMO

The ability to detect cancer early in an accurate and rapid fashion is of critical importance for cancer diagnosis and accurate resection in surgery. γ-Glutamyltranspeptidase (GGT) is overexpressed in several human cancers, while maintaining a low expression in normal microenvironments, and thus is recognized as an important cancer biomarker. To date, rational design of a zero cross-talk ratiometric near-infrared (NIR) GGT fluorescent probe for efficient cancer diagnosis in various biological samples is still a big challenge. In this work, a zero cross-talk ratiometric NIR GGT fluorescent probe named Cy-GSH is developed. Cy-GSH shows high sensitivity to GGT, which is desired for early cancer diagnosis. Upon additional GGT, a large emission shift from 805 to 640 nm is observed, which is suitable for visualizing deeply located cancer in vivo. In addition, successful monitoring of GGT activity in blood, cells, tissues, and in vivo makes Cy-GSH possess great potential for the clinical cancer early diagnosis. Furthermore, accurately visualizing tumors and metastases in mouse models illuminates that the probe may be a convenient tool for fluorescence-guided cancer surgery. To our knowledge, this is the first report to describe the strategy of a zero cross-talk ratiometric NIR GGT fluorescent probe for early cancer diagnosis and fluorescence-guided surgery.


Assuntos
Biomarcadores Tumorais/química , Técnicas Biossensoriais , Fluorescência , Corantes Fluorescentes/química , Imagem Óptica , gama-Glutamiltransferase/química , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular , Corantes Fluorescentes/metabolismo , Glutationa/química , Glutationa/metabolismo , Células HCT116 , Células Hep G2 , Humanos , Raios Infravermelhos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Estrutura Molecular , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/cirurgia , Espectrometria de Fluorescência , gama-Glutamiltransferase/metabolismo
15.
Environ Sci Technol ; 53(3): 1501-1508, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30592608

RESUMO

Graphene oxide (GO) membranes have the potential to be next-generation membranes. However, the GO layer easily swells in water and risks shedding during the long-term filtration. Organic GO interlayer organic cross-linking agent was not resistant to oxidation, which limits the application scope of GO membrane. In this study, an inorganic cross-linked GO membrane was prepared via the reaction of sodium tetraborate and GO hydroxyl groups, and a -B-O-C- cross-linking bond was detected by X-ray photoelectron spectroscopy (XPS). Additionally, a new atomic force microscope scratch method to evaluate the cross-linking force of a nanoscale GO layer was proposed. It showed that the critical destructive load of the inorganic cross-linked GO membrane increased from 8 to 80 nN, which was a 10-fold increase from that of the nonlinked sample. During the NaOH/sodium dodecyl sulfate (SDS) destructive wash tests, morphology, flux and retention rate of inorganic cross-linked GO remained stable while the comparative membranes showed significant destruction. At the same time, based on the better oxidation resistance, organic membrane fouling was effectively controlled by the introduction of trace ·OH radicals. This study provides a new perspective for GO membrane preparation, interlayer cross-linking force testing and membrane fouling control.


Assuntos
Grafite , Boratos , Filtração , Membranas Artificiais , Óxidos
17.
Anal Chem ; 90(15): 9418-9425, 2018 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-29973044

RESUMO

Intracellular viscosity is an essential microenvironmental parameter and H2S is a critical gaseous signaling molecule, which are both related to various physiological processes. It is reported that the change of viscosity and an imbalance of H2S production in the mitochondria are both associated with overexpression of amyloid betapeptide (Aß), which is thought to play a central role in the pathogenesis of Alzheimer's disease (AD). However, to our best knowledge, no fluorescent probe is found for dual detection of mitochondrial viscosity and H2S. Herein, a dual-response fluorescent probe (Mito-VS) is designed and synthesized to monitor the level of viscosity and H2S, respectively. Mito-VS itself is nonfluorescent due to a free intramolecular rotation between dimethylaniline and pyridine. After the increase of viscosity, the rotation is prohibited and an intense red fluorescence is released. Upon the addition of H2S, the probe can react with H2S to form compound 3 and a strong green fluorescence can be observed. Moreover, the probe possesses a good mitochondrion-targeting ability and is applied for imaging the change of viscosity on the red channel and visualizing the variation of exogenous and endogenous H2S concentration on the green channel in mitochondria. Most importantly, the probe is capable of studying the cross-talk influence of viscosity and H2S in mitochondria, which is very beneficial for knowing the pathogenesis of AD.


Assuntos
Corantes Fluorescentes/química , Sulfeto de Hidrogênio/análise , Mitocôndrias/química , Imagem Óptica/métodos , Viscosidade , Células HeLa , Humanos , Microscopia de Fluorescência/métodos , Mitocôndrias/ultraestrutura
18.
Environ Sci Technol ; 52(17): 9972-9982, 2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-30067345

RESUMO

The removal of low-concentration antibiotics from water to alleviate the potential threat of antibiotic-resistant bacteria and genes calls for the development of advanced treatment technologies with high efficiency. In this study, a novel graphene modified electro-Fenton (e-Fenton) catalytic membrane (EFCM) was fabricated for in situ degradation of low-concentration antibiotic florfenicol. The removal efficiency was 90%, much higher than that of electrochemical filtration (50%) and single filtration process (27%). This demonstrated that EFCM acted not only as a cathode for e-Fenton oxidation process in a continuous mode but also as a membrane barrier to concentrate and enhance the mass transfer of florfenicol, which increased its oxidation chances. The removal rate of florfenicol by EFCM was much higher (10.2 ± 0.1 mg m-2 h-1) than single filtration (2.5 ± 0.1 mg m-2 h-1) or batch e-Fenton processes (4.3 ± 0.05 mg m-2 h-1). Long-term operation and fouling experiment further demonstrated the durability and antifouling property of EFCM. Four main degradation pathways of florfenicol were proposed by tracking the degradation byproducts. The above results highlighted the feasibility of this integrated membrane catalysis process for advanced water purification.


Assuntos
Grafite , Poluentes Químicos da Água , Antibacterianos , Catálise , Peróxido de Hidrogênio , Ferro , Oxirredução , Tianfenicol/análogos & derivados
19.
J Nat Prod ; 78(6): 1294-9, 2015 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-26039736

RESUMO

Chemical investigation of the marine-sponge-derived fungus Penicillium adametzioides AS-53 resulted in the identification of two new bisthiodiketopiperazine derivatives, adametizines A (1) and B (2), from cultivation in a liquid potato-dextrose broth (PDB) culture medium, whereas two new acorane sesquiterpenes, adametacorenols A (3) and B (4), were isolated from a rice solid culture medium. The structures of these compounds were elucidated on the basis of spectroscopic analysis. The absolute configuration of compound 1 was determined by X-ray crystallographic analysis, and that of 3 was determined by modified Mosher's method. Compound 1 exhibited lethality against brine shrimp (Artemia salina) with an LD50 value of 4.8 µM and inhibitory activities against Staphyloccocus aureus, Aeromonas hydrophilia, Vibrio spp. V. harveyi and V. parahaemolyticus, and Gaeumannomyces graminis with minimum inhibitory concentration values of 8, 8, 32, 8, and 16 µg/mL, respectively. Chlorination at C-7 significantly increased the brine shrimp lethality and antimicrobial activity of the bisthiodiketopiperazines.


Assuntos
Antibacterianos/isolamento & purificação , Dicetopiperazinas/isolamento & purificação , Penicillium/química , Sesquiterpenos/isolamento & purificação , Aeromonas/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Artemia/efeitos dos fármacos , Cristalografia por Raios X , Meios de Cultura , Dicetopiperazinas/química , Dicetopiperazinas/farmacologia , Biologia Marinha , Testes de Sensibilidade Microbiana , Conformação Molecular , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Poríferos/microbiologia , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Vibrio/efeitos dos fármacos
20.
Front Pharmacol ; 15: 1374158, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38887554

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is marked by hepatic steatosis accompanied by an inflammatory response. At present, there are no approved therapeutic agents for NAFLD. Dendrobium Huoshanense polysaccharide (DHP), an active ingredient extracted from the stems of Dendrobium Huoshanense, and exerts a protective effect against liver injury. However, the therapeutic effects and mechanisms of action DHP against NAFLD remain unclear. DHP was extracted, characterized, and administered to mice in which NAFLD had been induced with a high-fat and high-fructose drinking (HFHF) diet. Our results showed that DHP used in this research exhibits the characteristic polysaccharide peak with a molecular weight of 179.935 kDa and is composed primarily of Man and Glc in a molar ratio of 68.97:31.03. DHP treatment greatly ameliorated NAFLD by significantly reducing lipid accumulation and the levels of liver function markers in HFHF-induced NAFLD mice, as evidenced by decreased serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total cholesterol (TC) and total triglyceride (TG). Furthermore, DHP administration reduced hepatic steatosis, as shown by H&E and Oil red O staining. DHP also inhibited the Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB) signaling pathway expression, thereby reducing levels of hepatic proinflammatory cytokines. Besides, untargeted metabolomics further indicated that 49 metabolites were affected by DHP. These metabolites are strongly associated the metabolism of glycine, serine, threonine, nicotinate and nicotinamide, and arachidonic acid. In conclusion, DHP has a therapeutic effect against NAFLD, whose underlying mechanism may involve the modulation of TLR4/NF-κB, reduction of inflammation, and regulation of the metabolism of glycine, serine, threonine, nicotinate and nicotinamide metabolism, and arachidonic acid metabolism.

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