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1.
J Biochem Mol Toxicol ; 38(2): e23647, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38348718

RESUMO

Hepatocellular carcinoma (HCC) is among the world's worst malignancies. Nuclear division cycle 1 (NDC1) is an essential membrane-integral nucleoporin, found in this study to be significantly increased in primary HCC. A multivariate analysis revealed that higher NDC1 expression was linked to worse outcome in HCC patients. Mouse xenograft tumors overexpressing NDC1 grew rapidly, and HCC cells overexpressing NDC1 showed enhanced proliferation, invasion, and migration in vitro. In contrast, knocking down NDC1 had the opposite effects in vitro. Furthermore, co-immunoprecipitation and liquid chromatograph mass spectrometer analyses revealed that NDC1 activated PI3K/AKT signaling by interacting with BCAP31. In summary, NDC1 and BCAP31 cooperate to promote the PI3K/AKT pathway, which is essential for HCC carcinogenesis. This suggests that NDC1 is predictive of prognosis in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Camundongos , Carcinogênese , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Divisão do Núcleo Celular , Proliferação de Células , Transformação Celular Neoplásica , Neoplasias Hepáticas/metabolismo , Proteínas de Membrana , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
2.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(5): 450-455, 2024 May 15.
Artigo em Zh | MEDLINE | ID: mdl-38802903

RESUMO

OBJECTIVES: To investigate the incidence rate, clinical characteristics, and prognosis of neonatal stroke in Shenzhen, China. METHODS: Led by Shenzhen Children's Hospital, the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022. The incidence, clinical characteristics, treatment, and prognosis of neonatal stroke in Shenzhen were analyzed. RESULTS: The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137, 1/6 060, and 1/7 704, respectively. Ischemic stroke accounted for 75% (27/36); boys accounted for 64% (23/36). Among the 36 neonates, 31 (86%) had disease onset within 3 days after birth, and 19 (53%) had convulsion as the initial presentation. Cerebral MRI showed that 22 neonates (61%) had left cerebral infarction and 13 (36%) had basal ganglia infarction. Magnetic resonance angiography was performed for 12 neonates, among whom 9 (75%) had involvement of the middle cerebral artery. Electroencephalography was performed for 29 neonates, with sharp waves in 21 neonates (72%) and seizures in 10 neonates (34%). Symptomatic/supportive treatment varied across different hospitals. Neonatal Behavioral Neurological Assessment was performed for 12 neonates (33%, 12/36), with a mean score of (32±4) points. The prognosis of 27 neonates was followed up to around 12 months of age, with 44% (12/27) of the neonates having a good prognosis. CONCLUSIONS: Ischemic stroke is the main type of neonatal stroke, often with convulsions as the initial presentation, involvement of the middle cerebral artery, sharp waves on electroencephalography, and a relatively low neurodevelopment score. Symptomatic/supportive treatment is the main treatment method, and some neonates tend to have a poor prognosis.


Assuntos
Acidente Vascular Cerebral , Humanos , Masculino , Recém-Nascido , Feminino , China/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Prognóstico , Eletroencefalografia , Incidência , Imageamento por Ressonância Magnética
3.
Molecules ; 28(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36838918

RESUMO

Confusoside (CF), a major chemical compound in the leaves of Anneslea fragrans Wall., is a dihydrochalcone glycoside with excellent antioxidant and anti-inflammatory effects. However, the hepatoprotective effect of CF has not been described. This study aimed to explore the hepatoprotective effect of CF against acetaminophen (APAP)-induced hepatic injury in HepG2 cells. First, the potential hepatoprotective effect mechanisms of CF were predicted by network pharmacology and were thought to involve reducing inflammation and inhibiting apoptosis. Target proteins (phosphatidylinositol3-kinase (PI3K) and caspase-3 (CASP3)) were found via molecular docking analysis. To verify the predicted results, an analysis of biological indicators was performed using commercial kits and Western blotting. The results showed that CF significantly decreased the levels of liver injury biomarkers (ALT, AST, and LDH), strongly inhibited the production of inflammatory cytokines (IL-1ß, IL-6, and TNF-α) and the NO level via inhibiting the activation of the NF-κB signaling pathway, and markedly regulated the expression levels of Bcl2, Bax, and cleaved-CASP3/9 proteins by activating the PI3K-CASP3 apoptosis pathway. The results demonstrated that CF has a therapeutic effect on APAP-induced liver injury by inhibiting intracellular inflammation and cell apoptosis, indicating that CF may be used as a potential reagent for the prevention and treatment of APAP-induced liver injury.


Assuntos
Acetaminofen , Doença Hepática Induzida por Substâncias e Drogas , Compostos Fitoquímicos , Humanos , Acetaminofen/efeitos adversos , Caspase 3/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Inflamação/metabolismo , Fígado , Simulação de Acoplamento Molecular , Estresse Oxidativo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Células Hep G2 , Compostos Fitoquímicos/farmacologia
4.
Neurochem Res ; 47(12): 3635-3646, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35522367

RESUMO

Satellite glial cells (SGCs) tightly surround neurons and modulate sensory transmission in dorsal root ganglion (DRG). At present, the biological property of primary SGCs in culture deserves further investigation. To reveal the key factor for SGCs growth and survival, we examined the effects of different culture supplementations containing Dulbecco's Modified Eagle Medium (DMEM)/F12, DMEM high glucose (HG) or Neurobasal-A (NB). CCK-8 proliferation assay showed an increased proliferation of SGCs in DMEM/F12 and DMEM/HG, but not in NB medium. Bax, AnnexinV, and propidium iodide (PI) staining results showed that NB medium caused cell death and apoptosis. We showed that glutamine was over 2.5 mM in DMEM/F12 and DMEM/HG, whereas it was absence in NB medium. Interestingly, exogenous glutamine application significantly reversed the poor proliferation and cell death of SGCs in NB medium. These findings demonstrated that DMEM/F12 medium was optimal to get high-purity SGCs. Glutamine was the key molecule to maintain SGCs growth and survival in culture. Here, we provided a novel approach to get high-purity SGCs by changing the key component of culture medium. Our study shed a new light on understanding the biological property and modulation of glial cells of primary sensory ganglia.


Assuntos
Glutamina , Neuroglia , Glutamina/farmacologia , Glutamina/metabolismo , Neuroglia/metabolismo , Neurônios , Gânglios Espinais , Apoptose
5.
EMBO Rep ; 21(8): e50095, 2020 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-32558197

RESUMO

tRNA modifications at the anti-codon loop are critical for accurate decoding. FTSJ1 was hypothesized to be a human tRNA 2'-O-methyltransferase. tRNAPhe (GAA) from intellectual disability patients with mutations in ftsj1 lacks 2'-O-methylation at C32 and G34 (Cm32 and Gm34). However, the catalytic activity, RNA substrates, and pathogenic mechanism of FTSJ1 remain unknown, owing, in part, to the difficulty in reconstituting enzymatic activity in vitro. Here, we identify an interacting protein of FTSJ1, WDR6. For the first time, we reconstitute the 2'-O-methylation activity of the FTSJ1-WDR6 complex in vitro, which occurs at position 34 of specific tRNAs with m1 G37 as a prerequisite. We find that modifications at positions 32, 34, and 37 are interdependent and occur in a hierarchical order in vivo. We also show that the translation efficiency of the UUU codon, but not the UUC codon decoded by tRNAPhe (GAA), is reduced in ftsj1 knockout cells. Bioinformatics analysis reveals that almost 40% of the high TTT-biased genes are related to brain/nervous functions. Our data potentially enhance our understanding of the relationship between FTSJ1 and nervous system development.


Assuntos
Deficiência Intelectual , Códon , Humanos , Deficiência Intelectual/genética , Metilação , Metiltransferases/genética , Metiltransferases/metabolismo , Proteínas Nucleares/metabolismo , RNA de Transferência/genética , RNA de Transferência/metabolismo , tRNA Metiltransferases/genética , tRNA Metiltransferases/metabolismo
6.
Bioorg Chem ; 120: 105607, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35033818

RESUMO

Melodinus cochinchinensis (Lour.) Merr. is a Yunnan endemic folk medicine. Our previous study showed that 11-methoxytabersonine (11-MT) isolated from M. cochinchinensis has strong cytotoxicity on human T-ALL cells, but its molecular mechanism has not been studied. In current study, the cytotoxicity and possible mechanism of 11-MT on T-cell acute lymphoblastic leukemia was explored using network pharmacology and molecular biology techniques. 11-MT significantly inhibited the cell proliferations on different four human T-ALL cells (MOLT-4, Jurkat, CCRF-CEM, and CEM/C1 cells). 11-MT triggered ROS accumulation, calcium concentration and cell apoptosis, and decreased the mitochondrial membrane potential (MMP) in human T-ALL cells, especially MOLT-4 cells. Western blot analysis showed that it can induce MOLT-4 cell apoptosis by up-regulating PI3K/Akt signaling pathway. Therefore, 11-MT induces human T-ALL cells apoptosis via up-regulation of ROS-mediated mitochondrial dysfunction and down-regulation of PI3K/Akt/mTOR signaling pathway.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Proteínas Proto-Oncogênicas c-akt , Apoptose , Linhagem Celular Tumoral , China , Humanos , Alcaloides Indólicos , Mitocôndrias/metabolismo , Monoterpenos , Farmacologia em Rede , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio , Transdução de Sinais
7.
Molecules ; 27(11)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35684371

RESUMO

The bud of Vaccinium dunalianum Wight has been traditionally consumed as health herbal tea by "Yi" people in Yunnan Province, China, which was locally named "Que Zui tea". This paper studied the chemical constituents of five fractions from Vaccinium dunalianum, and their enzyme inhibitory effects of α-glucosidase and pancreatic lipase, antioxidant activity, and cytoprotective effects on H2O2-induced oxidative damage in HepG2 cells. The methanol extract of V. dunalianum was successively partitioned with petroleum ether (PF), chloroform (CF), ethyl acetate (EF), n-butanol (BF), and aqueous (WF) to obtain five fractions. The chemical profiling of the five fractions was analyzed by ultra-high-performance liquid chromatography coupled with a tandem mass spectrometry (UHPLC-MS/MS), and 18 compounds were tentatively identified. Compared to PF, CF, BF and WF, the EF revealed the highest total phenols (TPC) and total flavonoids (TFC), and displayed the strongest enzyme inhibition ability (α-glucosidase and pancreatic lipase) and antioxidant capacity (DPPH, ABTS and FRAP). Furthermore, these five fractions, especially EF, could effectively inhibit reactive oxygen species (ROS) production and cell apoptosis on H2O2-induced oxidative damage protection in HepG2 cells. This inhibitory effect might be caused by the up-regulation of intracellular antioxidant enzyme activity (CAT, SOD, and GSH). The flavonoids and phenolic acids of V. dunalianum might be the bioactive substances responsible for enzyme inhibitory, antioxidant, and cytoprotective activities.


Assuntos
Antioxidantes , Vaccinium , Antioxidantes/química , China , Flavonoides/química , Humanos , Peróxido de Hidrogênio/análise , Lipase , Fenóis/análise , Fenóis/farmacologia , Extratos Vegetais/química , Espectrometria de Massas em Tandem , alfa-Glucosidases
8.
J Nat Prod ; 84(6): 1772-1779, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34033480

RESUMO

Induced water hyacinth with purple roots (PRWH) exerts a significant inhibitory effect on the growth of blue-green algae. Interestingly, its chemical constituents differ from those of wild-type water hyacinth and have not yet been reported. This study aimed to explore the chemical constituents of PRWH and its bioactive components serving as allelopathic agents against blue-green algae. Phytochemical investigation of the bioactive ethyl acetate fraction of a crude methanol extract from PRWH led to the isolation of 56 compounds, including 11 new phenylphenalene derivatives. The structures of these compounds were elucidated by comprehensive analyses through NMR, HRMS, and X-ray techniques. Bioactivity evaluation against Microcystis aeruginosa indicated that compounds 7, 12, 15, 37, 39, 45, and 47 potently inhibited blue-green algae growth.


Assuntos
Alelopatia , Eichhornia/química , Microcystis/efeitos dos fármacos , Extratos Vegetais/farmacologia , China , Estrutura Molecular , Compostos Fitoquímicos/farmacologia , Raízes de Plantas/química
9.
Surg Endosc ; 35(10): 5852-5856, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34076766

RESUMO

BACKGROUND: A large gastrointestinal perforation is a serious and even life-threatening clinical condition. Current endoscopic techniques for closing large gastrointestinal perforation have limitations. Building upon our recent findings in a porcine model, this pilot human study aimed to evaluate the safety, feasibility, and effectiveness of a novel endoscopic technique using newly designed closure clips for closure of giant gastrointestinal perforation. METHODS: A total of 18 patients who underwent endoscopic submucosal dissection (ESD) and developed giant gastrointestinal perforation > 2 cm in diameter were enrolled in this study. The newly designed closure clips, consisting of a sewing clip and knotter, were applied in endoscopic closure of the gastrointestinal perforations using a continuous suturing method. The safety, feasibility, and effectiveness were subsequently assessed in these patients. RESULTS: Endoscopic closure of the giant perforation was achieved in all patients. In evaluation of safety and effectiveness of this technique with the new closure clips and the continuous suturing method, no obvious intraoperative complications (e.g., bleeding, abdominal infection) occurred in the studied patients. Furthermore, on 1-month follow-up gastric endoscopy, all the patients showed complete closure of the gastrointestinal perforations, and no clinical signs of specific abnormalities or symptoms were observed. CONCLUSION: This novel technique has been shown to be safe, effective, and feasible for the treatment of giant gastrointestinal perforation.


Assuntos
Ressecção Endoscópica de Mucosa , Perfuração Intestinal , Animais , Humanos , Perfuração Intestinal/etiologia , Perfuração Intestinal/cirurgia , Instrumentos Cirúrgicos , Técnicas de Sutura , Suínos , Técnicas de Fechamento de Ferimentos
10.
Ecotoxicology ; 30(7): 1366-1375, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33131022

RESUMO

With wide use of nanoparticles, co-exposure of aquatic organisms to nanoparticles and organic pollutants often takes place in the environment. However, the combined effects are still rarely understood. In this study, in order to study the interaction and biological effects of nanoscale zero-valent iron (nZVI) and linear alkylbenzene sulfonate (LAS), which acts as a typical surfactant, the freshwater algae Scenedesmus obliquus was exposed to nZVI and LAS individually and in combination for 96 h. According to the inhibition rate of the algae, the toxic effects were investigated by dose-response analysis. Then the combined effect of nZVI and LAS was evaluated using three evaluation models including toxicity unit (TU), additional index (AI), and mixture toxicity index (MTI). The results showed that the 96 h IC50 of nZVI and LAS to Scenedesmus obliquus was 2.464 mmol L-1 and 0.332 mmol L-1, respectively. When nZVI coexisted with LAS at toxic ratio 1:1, the 96 h IC50 value was 1.658 mmol L-1 (shown with nZVI), and the partly additive effect of nZVI mixed with LAS was confirmed. However, when the toxic ratio of nZVI:LAS was 4:1, it showed synergistic effect. In addition, when nZVI mixed with LAS at toxic ratio 1:4, the joint effect is antagonistic effect. In addition, the content of chorophyll in Scenedesmus obliquus, especially the content of chlorophyll a, was decreased with the increase of mixture dose. However, the protein levels did not show significant changes at different mixture doses.


Assuntos
Scenedesmus , Poluentes Químicos da Água , Ácidos Alcanossulfônicos , Clorofila A , Água Doce , Ferro/toxicidade , Poluentes Químicos da Água/toxicidade
11.
Chem Biodivers ; 18(5): e2100084, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33682992

RESUMO

4,21-Secovincanol (1), a novel C-21/N-4 cleavage monoterpenoid indole alkaloid, along with four analogs (2-5), were obtained from the aerial parts of Kopsia hainanensis. Structurally, compound 1 might be a derivative of epivincanol (2) via C-21/N-4 cleavage. Their structures were confirmed by means of comprehensive spectroscopic data analysis and comparison with the reported data. All isolates significantly inhibited Con A-stimulated mice splenocytes proliferation at 10-40 µM in a dose-dependent manner in vitro. Especially, compound 3 exhibited potent activities comparable to positive control (Dexamethasone, DXM).


Assuntos
Apocynaceae/química , Imunossupressores/farmacologia , Extratos Vegetais/farmacologia , Baço/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Concanavalina A/antagonistas & inibidores , Concanavalina A/farmacologia , Relação Dose-Resposta a Droga , Imunossupressores/química , Imunossupressores/isolamento & purificação , Camundongos , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação
12.
Org Biomol Chem ; 18(20): 3848-3852, 2020 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-32400817

RESUMO

The total synthesis of six novel okaramines (C, J, L, and S-U) was accomplished with a precise synthesis scheme involving a few steps and a practical yield of 6.7%-23% was obtained. The significance of this study includes the design of a successful and convenient synthesis method for preparation of 3a-hydroxy-pyrrolo[2,3-b]-indole and C-7 prenylated l-tryptophan derivatives using a nucleophilic attack of cyclopropylazetoindoline and an aza-Claisen rearrangement of N-reverse-prenyl tryptophan, respectively.

13.
Exp Cell Res ; 383(1): 111502, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31323191

RESUMO

Brain-derived neurotropic factor (BDNF) deficiency in Schwann cells plays an important role in the pathogenesis of diabetic peripheral neuropathy (DPN). Little is known about the mechanism involved in BDNF downregulation in Schwann cells in DPN. In this study, we first confirmed downregulation of BDNF and neurotrophin 3 expression in the sciatic nerves of diabetic mice, which was accompanied by myelin sheath abnormalities. Moreover, in vitro, high glucose was revealed to cause downregulation of BDNF, but not neurotrophin 3, expression in RSC96 cells, which was accompanied by DNA hypermethylation of BDNF promoters I and II. DNMT1 was subsequently revealed to be enhanced at the mRNA and protein levels in high glucose-stimulated RSC96 cells, and inhibition of DNMT1 with 5-Aza treatment or shRNA vector transfection reversed high glucose-induced reductions in BDNF expression. Furthermore, the mTOR and upstream Akt pathways were indicated to mediate high glucose-induced DNMT1 and BDNF expression in RSC96 cells. Taken together, our results suggest that the Akt/mTOR cascade mediates high glucose-induced reductions in BDNF via DNMT1 in Schwann cells in DPN.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Neuropatias Diabéticas/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células de Schwann/patologia , Serina-Treonina Quinases TOR/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Células Cultivadas , Metilação de DNA , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Neuropatias Diabéticas/etiologia , Neuropatias Diabéticas/metabolismo , Regulação para Baixo , Masculino , Camundongos , Neurotrofina 3/genética , Neurotrofina 3/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Células de Schwann/efeitos dos fármacos , Células de Schwann/metabolismo , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/metabolismo , Nervo Isquiático/patologia , Edulcorantes/farmacologia , Serina-Treonina Quinases TOR/genética
14.
Mar Drugs ; 19(1)2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33379196

RESUMO

Three new phenylhydrazones, penoxahydrazones A-C (compounds 1-3), and two new quinazolines, penoxazolones A (compound 4) and B (compound 5), with unique linkages were isolated from the fungus Penicillium oxalicum obtained from the deep sea cold seep. Their structures and relative configurations were assigned by analysis of 1D/2D NMR and mass spectroscopic data, and the absolute configurations of 1, 4, and 5 were established on the basis of X-ray crystallography or ECD calculations. Compound 1 represents the first natural phenylhydrazone-bearing steroid, while compounds 2 and 3 are rarely occurring phenylhydrazone tautomers. Compounds 4 and 5 are enantiomers that feature quinazoline and cinnamic acid units. Some isolates exhibited inhibition of several marine phytoplankton species and marine-derived bacteria.


Assuntos
Antibacterianos/farmacologia , Hidrazonas/farmacologia , Penicillium/metabolismo , Quinazolinas/farmacologia , Antibacterianos/isolamento & purificação , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Sedimentos Geológicos/microbiologia , Hidrazonas/isolamento & purificação , Estrutura Molecular , Fitoplâncton/efeitos dos fármacos , Fitoplâncton/crescimento & desenvolvimento , Quinazolinas/isolamento & purificação , Relação Estrutura-Atividade
15.
Chemistry ; 25(51): 11933-11939, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31310395

RESUMO

Electrochemical reduction of N2 to NH3 is a promising method for artificial N2 fixation, but it requires efficient and robust electrocatalysts to boost the N2 reduction reaction (NRR). Herein, a combination of experimental measurements and theoretical calculations revealed that a hybrid material in which ZnO quantum dots (QDs) are supported on reduced graphene oxide (ZnO/RGO) is a highly active and stable catalyst for NRR under ambient conditions. Experimentally, ZnO/RGO was confirmed to favor N2 adsorption due to the largely exposed active sites of ultrafine ZnO QDs. DFT calculations disclosed that the electronic coupling of ZnO with RGO resulted in a considerably reduced activation-energy barrier for stabilization of *N2 H, which is the rate-limiting step of the NRR. Consequently, ZnO/RGO delivered an NH3 yield of 17.7 µg h-1 mg-1 and a Faradaic efficiency of 6.4 % in 0.1 m Na2 SO4 at -0.65 V (vs. RHE), which compare favorably to those of most of the reported NRR catalysts and thus demonstrate the feasibility of ZnO/RGO for electrocatalytic N2 fixation.

16.
Inorg Chem ; 58(15): 10424-10431, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31347359

RESUMO

The development of highly active and durable electrocatalysts toward the N2 reduction reaction (NRR) holds a key to ambient electrocatalytic NH3 synthesis. Herein, fluorine (F)-doped SnO2 mesoporous nanosheets on carbon cloth (F-SnO2/CC) were developed as an efficient NRR electrocatalyst. Benefiting from the combined structural advantages of mesoporous nanosheet structure and F-doping, the F-SnO2/CC exhibited high NRR activity with an NH3 yield of 19.3 µg h-1 mg-1 and a Faradaic efficiency of 8.6% at -0.45 V (vs RHE) in 0.1 M Na2SO4, comparable or even superior to those of most reported NRR electrocatalysts. Density functional theory calculations revealed that the F-doping could readily tailor the electronic structure of SnO2 to render it with improved conductivity and increased positive charge on active Sn sites, leading to the lowered reaction energy barriers and boosted NRR activity.

17.
Bioorg Med Chem ; 26(8): 1776-1783, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29486949

RESUMO

Unlike reported bisindoles linked by single bond directly, alstoniasidines A (1) and B (2), from Alstonia scholaris featuring unprecedented skeleton with two indole moieties bridged by a sugar, represented a novel bisindole type having strictosamide-glucopyranose-picraline scaffold. Both compounds exhibited selective cytotoxicity against human glioma stem cells (GSCs) and induced caspase-3 dependent extrinsic apoptosis by increasing the expression of interleukin 1 (IL-1), tumor necrosis factor (TNF-α), and the cleaved caspase-3, while damaged the unlimited proliferation and self-renewal capacity of GSCs. This finding might provide new type of leads for the selective killing of human glioma stem cells.


Assuntos
Alstonia/química , Antineoplásicos/farmacologia , Glioma/tratamento farmacológico , Indóis/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Açúcares/química , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glioma/patologia , Humanos , Indóis/química , Indóis/isolamento & purificação , Estrutura Molecular , Folhas de Planta/química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
18.
J Nanosci Nanotechnol ; 18(2): 1027-1033, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29448528

RESUMO

The waterborne pathogenic viruses threaten human health. And the nanomaterial-membrane coupling system is promising in virus removal. In this study, phage MS2 was selected as the model virus to investigate the removal of virus with the coupling system. Results revealed that commercial nano TiO2 (Degussa Aeroxide P25) showed both of excellent adsorption and photocatalysis performance for virus removal compared with nano ZnO, nano Fe3O4, carbon nanotube, graphene, nano Ni and Nano TiO2 (anatase). In P25 photocatalysis process, the removal efficiency of phage MS2 increased with the increase of P25 concentration (0~1000 mg L-1), virus initial concentration (102~106 PFU mL-1), UV irradiation doses (5~120 mJ cm-2) and UV light intensity (0.126~0.742 mW cm-2). However, when the P25 concentration increased to over 1000 mg L-1, the virus removal efficiency would remain stable with the increase of P25 concentration. The nanomaterial-membrane coupling system showed excellent performance for virus removal, which was mainly attributed to the adsorption and photocatalysis of P25, and the intercept of membrane. When the P25 concentration was 100 mg L-1, UV irradiation dose was 20 mJ cm-2 and transmembrane pressure was 20 kPa, the phage MS2 removal efficiency could be up to 100%.


Assuntos
Nanoestruturas , Titânio , Raios Ultravioleta , Vírus/isolamento & purificação , Purificação da Água , Adsorção , Catálise , Grafite , Luz
19.
Biochem Biophys Res Commun ; 489(4): 361-368, 2017 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-28479245

RESUMO

In acute lung injury/acute respiratory distress syndrome (ALI/ARDS), pathogenesis is associated with the regulation of macrophage-generated oxidative stress, and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX)-derived reactive oxygen species(ROS) are key to regulating oxidative stress. In the present study, we found that miR-19 inhibited the expression of p47phox in macrophages, resulting in the alleviation of the lipopolysaccharides(LPS)-induced inflammatory response. In a mouse LPS-induced model of lung injury, miR-19-deficient murine lung tissue was more susceptible to inflammatory responses and exhibited a higher infiltration rate, a higher number of inflammatory cells in the lungs, a higher level of inflammatory cytokines in the Bronchoalveolar lavage fluid (BALF), and more severe pathological damage in lung tissues. Moreover, following stimulation with LPS, p47phox was expressed at lower levels in miR-19-deficient murine pulmonary inflammatory cells than in those in wild-type rats. In LPS-treated Raw264.7 macrophages, miR-19 mimics blocking the down-regulation of LPS-induced p47phox expression, the accumulation of ROS, and the release of inflammatory cytokines. When siRNA was used to interfere with p47phox expression following stimulation with LPS, a lower level of ROS-mediated inflammatory cytokines were released. We found that the accumulation of ROS inhibited the LPS-induced release of inflammatory cytokines, the upregulation of miR-19 and the down-regulation of LPS-induced p47phox expression. Finally, we constructed a p47phox 3'UTR luciferase reporter plasmid to provide direct confirmation that miR-19 targets p47phox expression. The results of this study indicate the presence of a mechanism by which miR-19 regulates oxidative stress in macrophages. These data also provide potential targets for studies aimed at developing therapies for ARDS.


Assuntos
Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , MicroRNAs/antagonistas & inibidores , NADPH Oxidases/metabolismo , RNA Interferente Pequeno/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Células Cultivadas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/metabolismo , Células RAW 264.7
20.
Bioorg Med Chem Lett ; 27(13): 2863-2867, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28487072

RESUMO

Glioblastoma multiform (GBM) is a highly aggressive brain tumor with poor life expectancy, and glioma stem cells (GSCs) are a small population of tumor cells existed in GBM, in which GSCs response to drive GBM recurrence, invasion and contribute to the anti-cancer resistance. GSCs have been identified and developed as a therapeutic target for GBM and can be used in drugs screening. Isocostunolide is a natural sesquiterpenoid and contained abundant resource in medicinal plants, but the anti-cancer efficacies of it against GSCs are still unexplored. In this investigation, the anti-tumor activity of isocostunolide against GSCs was investigated and the result demonstrated that it inhibited the growth of GSCs (GSC-3#, GSC-12#, GSC-18#) significantly with an IC50 value of 2.80µg/ml, 2.61µg/ml, 1.07µg/ml, respectively. In further mechanism study, isocostunolide inhibited GSCs cell proliferation, induced GSCs apoptosis significantly, as well as increased the proportion of the cleavage of caspase-3. The result suggested that isocostunolide induced GSCs apoptosis via the caspase dependent apoptotic pathway. Moreover, isocostunolide damaged GSCs colony formation capacity significantly and exhibited the anti-cancer efficacy against GSCs in vitro.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Caspase 3/metabolismo , Inibidores de Caspase/farmacologia , Glioma/tratamento farmacológico , Sesquiterpenos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias Encefálicas/patologia , Inibidores de Caspase/síntese química , Inibidores de Caspase/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glioma/patologia , Humanos , Estrutura Molecular , Sesquiterpenos/síntese química , Sesquiterpenos/química , Relação Estrutura-Atividade
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