Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Int J Environ Health Res ; : 1-9, 2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34365848

RESUMO

Trichloroacetic acid (TCA) is a common non-volatile by-product of chlorination disinfection for drinking water. It is necessary to know the epigenetic toxicity and mechanisms for establishing safe exposure limit for environmental TCA exposure. This study explored the histone modification variations of TCA-treated human hepatocytes L-02 at different time and concentrations. TCA (0.1 mM, 0.3 mM and 0.9 mM) had an inhibitory effect on the growth of L-02 cells, with no significant changes in morphology. Treated with TCA for 24 h and 48 h, L-02 cells showed decreased mRNA and protein level of histone deacetylases (HDACs), but increased after 72 h. The downregulation of HDACs in early stage of TCA exposure might be one of the important reasons for the increase of H3K9ac level. These changes of histone modification may serve as early epigenetic biomarkers for TCA exposure and the related diseases, offering the safe environmental exposure concentration reference.

2.
Life Sci ; 282: 119814, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34298039

RESUMO

Sepsis is commonly complicated by acute lung injury (ALI). We aimed to determine the long non-coding RNAs (lncRNAs) and mRNAs expression profiles. Septic acute lung injury mouse model was established by cecal ligation and puncture. LPS was applied to induce inflammation in mouse alveolar macrophages (MH-s). Besides, LPS/Nigericin sodium salt was used to activate inflammasome in MH-s. LncRNA and mRNA profiles were detected using an Agilent microarray and identified by qPCR. Bioinformatic analyses were employed to analyze the expression profiles and multiple biological functions. Inflammation-related mRNAs were selected according to KEGG pathways and GO terms including inflammation response, immune response and cytokine activity. A network of inflammation related mRNAs and co-expressed lncRNAs was conducted. Finally, Gm33647 was identified as potential regulator in septic acute lung injury. Gm33647 was knock-downed via siRNA to explore functions. The results showed 353 differentially expressed lncRNAs and 3116 differentially expressed mRNAs were identified. Co-expression networks of lncRNA-mRNA showed Gm33647 was a hub gene. Cis- and trans-regulation analyses revealed Gm41442, Gm38850 and Gm36841 could function as a network in septic ALI. LncRNA Gm33647 was reduced by LPS and increased by inflammasome activation in MH-s. Silencing Gm33647 up-regulated IL-6, IL10 and TNF-α in MH-s. When inflammasome was activated by LPS/Nigericin sodium salt, IL-1ß, IL-18 and Caspase 1 were increased by silencing Gm33647 in MH-s. These results identified inflammation related lncRNAs and Gm33647 as potential regulators in septic ALI.


Assuntos
Lesão Pulmonar Aguda/imunologia , RNA Longo não Codificante/imunologia , RNA Interferente Pequeno/imunologia , Sepse/imunologia , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/patologia , Animais , Citocinas/genética , Citocinas/imunologia , Masculino , Camundongos , RNA Longo não Codificante/genética , RNA Interferente Pequeno/genética , Sepse/genética , Sepse/patologia
3.
J Sep Sci ; 44(7): 1510-1520, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33492709

RESUMO

Dispersive liquid-liquid microextraction has garnered increasing attention in sample preparation due to its rapid and efficient extraction process. In this study, a new terpineol-based hydrophobic deep eutectic solvent was firstly synthesized by mixing α-terpineol with 1-octanoic acid, and then applied to analysis of phenols from water samples by dispersive liquid-liquid microextraction combined with high-performance liquid chromatography and diode array detection. Infrared spectroscopy indicated that hydrogen bonding was responsible for the formation of deep eutectic solvent between α-terpineol and 1-octanoic acid. After optimization of several parameters, such as the type and volume of deep eutectic solvent and the disperser, pH and ionic strength of sample solution, the developed method exhibited excellent extraction performance to the phenols with the enrichment factors from 27 to 32. Good linearity was acquired ranging from 5 to 5000 µg/L, and detection of limits of the proposed method for the phenols ranged from 0.15 to 0.38 µg/L. The recoveries measured by spiked samples at three concentration levels ranged from 81.6 to 99.3%, and precision was found with intra- and inter-day relative standard deviations less than 8.7 and 9.2%, respectively. Finally, the proposed method was successfully applied to the determination of the phenols in environmental water samples.

4.
Br J Pharmacol ; 178(3): 689-708, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33169358

RESUMO

BACKGROUND AND PURPOSE: In humans, blood flow in the mesenteric circulation is greatly increased after meals, but the mechanisms underlying postprandial mesenteric vasorelaxation induced by nutrients and whether this process is involved in the pathogenesis of colitis, are not well understood. Here we have studied the direct actions of nutrients on mesenteric arterial tone and the underlying molecular mechanisms in healthy and colitis mice. EXPERIMENTAL APPROACH: Colitis in C57BL/6 mice was induced with dextran sodium sulphate. Nutrient-induced vasorelaxation of mesenteric arterioles from humans and mice was studied with wire myograph assays. Ca2+ and Na+ imaging were performed in human vascular endothelial cells and vascular smooth muscle cells, using selective pharmacological agents and shRNA knockdown of TRPV1 channels. KEY RESULTS: Glucose, sodium and mannitol concentration-dependently induced endothelium-dependent relaxation of human and mouse mesenteric arterioles via hyperosmotic action,. Hyperosmosis-induced vasorelaxation was almost abolished by selective blockers for TRPV1, IKCa and SKCa channels. Glucose markedly stimulated Ca2+ influx through endothelial TRPV1 channels, an effect attenuated by selective blockers and shRNA knockdown of TRPV1 channels. Capsaicin synergised the glucose-induced vasorelaxation. Nutrient-induced hyperosmosis also activated Na+ /K+ -ATPase and the Na/Ca exchanger (NCX) to decrease [Ca2+ ]i in VSMCs. Glucose-induced vasorelaxation was impaired in mouse colitis. CONCLUSION AND IMPLICATIONS: Nutrient-induced hyperosmosis evoked endothelium-dependent mesenteric vasorelaxation via the TRPV1/Ca2+ / endothelium-dependent hyperpolarisation pathway to increase normal mucosal perfusion, which is impaired in our model of colitis. The TRPV1/Ca2+ / endothelium-dependent hyperpolarisation pathway could provide novel drug targets for gastrointestinal diseases with hypoperfusion, such as chronic colitis and mesenteric ischaemia.


Assuntos
Colite , Vasodilatação , Animais , Colite/induzido quimicamente , Células Endoteliais , Endotélio Vascular , Artérias Mesentéricas , Camundongos , Camundongos Endogâmicos C57BL , Nutrientes , Canais de Cátion TRPV
5.
Nat Prod Res ; 35(10): 1596-1604, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-31204495

RESUMO

To find a potent α-glucosidase inhibitor, 24 tyrosol derivatives with different substituents located at the meta, ortho, or para position of the phenyl group have been synthesised via the Mitsunobu reaction, characterised by 1H NMR, 13C NMR, ESI-MS and IR and evaluated for inhibition. The derivatives possessed varying degrees of in vitro inhibitory activity against α-glucosidase and a relationship between the structure and activity was subsequently established for all compounds. Two of these compounds with substituents at the para position showed significant inhibitory effects surpassing that of the control standard acarbose. Molecular docking studies performed to better understand the binding interactions between the enzyme and the two most active compounds showed substantial binding within the active site of α-glucosidase. Taken together, these results indicate that the position of the substituent plays a crucial role in this inhibition and may facilitate the development of new α-glucosidase inhibitors.


Assuntos
Inibidores de Glicosídeo Hidrolases/farmacologia , Simulação de Acoplamento Molecular , Álcool Feniletílico/análogos & derivados , alfa-Glucosidases/metabolismo , Acarbose/química , Acarbose/farmacologia , Sítios de Ligação , Domínio Catalítico , Inibidores de Glicosídeo Hidrolases/química , Álcool Feniletílico/síntese química , Álcool Feniletílico/química , Álcool Feniletílico/farmacologia , Relação Estrutura-Atividade , Leveduras/enzimologia , alfa-Glucosidases/química
6.
Nat Prod Res ; 35(2): 346-349, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31177847

RESUMO

The aerial parts of Artemisia gmelinii Weber ex Stechm were collected from the northeast of China. The essential oil was obtained by hydrodistillation and analysed by GC-MS. A set of 66 compounds were identified representing 99.1% of the oil composition. The major compounds in the oil were cyclobutaneethanol, endo-borneol, germacrene D, eucalyptol, selin-6-en-4α-ol, bisabolone oxide A, caryophyllene and terpinen-4-ol. Moreover, the essential oil was evaluated for its antioxidant, antidiabetic, and anticholinesterase activities in vitro. Additionally, the antioxidant potential of the oil was evaluated using DPPH and ABTS assays. The oil showed good antidiabetic activity with an IC50 of 63.2 µg/mL, which was similar to that of the positive control acarbose, and weak anticholinesterase activities. These findings demonstrated that the essential oil of Artemisia gmelinii may be a good natural antidiabetic.


Assuntos
Artemisia/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Acetilcolinesterase/metabolismo , Antioxidantes/química , Butirilcolinesterase/metabolismo , China , Eucaliptol/análise , Cromatografia Gasosa-Espectrometria de Massas , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Hipoglicemiantes/química , Hipoglicemiantes/farmacologia , Simulação de Acoplamento Molecular , Componentes Aéreos da Planta/química , Sesquiterpenos Policíclicos/análise , Sesquiterpenos/análise , Sesquiterpenos/química , Sesquiterpenos de Germacrano/análise , Sesquiterpenos de Germacrano/química , Terpenos/análise
7.
Huan Jing Ke Xue ; 41(7): 3315-3325, 2020 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-32608905

RESUMO

Wheat straw biochar (BC) was modified by KOH and magnetics to generate composited modified biochar (FKC). Based on characterization by scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), Brunauer-Emmett-Teller (BET), Fourier transform infrared (FT-IR), X-ray diffraction (XRD), and magnetic (VSM) techniques, the adsorption characteristics and mechanisms of Cd2+ in water and the effects of temperature, pH value, and dosage on the adsorption characteristics of FKC were studied. The results showed that the modified biochar was loose and porous. The specific surface area of FKC increased by 19.11 times, the number of aromatic and oxygen-containing functional groups such as O-H, C=O, and C=C increased, and a new functional group Fe-O formed compared to the BC. FKC is magnetic, and its magnetization is 8.43 emu·g-1, which can be recycled and reused. The adsorption of Cd2+ by FKC fitted well with the pseudo-second-order kinetic model and the Langmuir model, indicating that chemical adsorption is the main adsorption mechanism. The theoretical maximum equilibrium adsorption capacity of FKC is 23.44 mg·g-1, which is 1.47 times that of BC. The thermodynamic parameters suggested the adsorption of Cd2+ by FKC was a spontaneous and endothermic process. The adsorption capacity increased with an increase of pH in the region 2-8, and a biochar dosage of 10 g·L-1 was used. After three cycles of adsorption-desorption-adsorption, the adsorption capacity of Cd2+ by FKC still reached 17.71 mg·g-1, indicating that FKC has good reusability. These results can provide a theoretical basis for the application of KOH and magnet-modified biochar from wheat straw to remove heavy metals from contaminated wastewater.

8.
Environ Sci Pollut Res Int ; 27(25): 31505-31515, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32495199

RESUMO

Wide application of nanoparticles causes considerable environmental, health, and safety problems. However, their potential impact and mechanisms on plant growth are not completely clear. In the present study, the effects of different concentration of copper oxide nanoparticles (nCuO) on seed germination and seedling growth, as well as physiological parameters of Brassica pekinensis L., were investigated. The seeds were exposed to 10-, 100-, and 1000-mg L-1 nCuO suspensions and 0.8-mg L-1 Cu2+ released from 1000-mg L-1 nCuO for 7 day. The results showed that nCuO did not affect the germination rate, germination potential, and germination index of B. pekinensis but significantly affected the vitality index. The growth of roots and shoots of B. pekinensis was promoted at 10-mg L-1 nCuO, while they were inhibited under 1000-mg L-1 nCuO and Cu2+ ion treatments, and roots suffered more damage than shoots. Cu content in shoots and roots of B. pekinensis increased with increasing concentrations of nCuO, which is significantly higher in roots as compared with shoots. Roots and shoots accumulated more Cu under nCuO treatments compared with Cu2+ ion treatment. nCuO treatments led to significant lignification in roots of B. pekinensis. Furthermore, nCuO increased in the contents of soluble sugar and protein in shoots, while nCuO at 1000 mg L-1 significantly inhibited the content of soluble protein in roots. In addition, concentration-dependent augmentation of lipid peroxidation, hydrogen peroxide and superoxide generation, and antioxidant enzyme activity were noticed in shoots and roots of B. pekinensis seedlings under nCuO and Cu2+ ion treatments. Altogether, the results strongly suggested that the phytotoxicity of nCuO in B. pekinensis was caused by both the nanoparticles itself and the released Cu2+ ions.


Assuntos
Brassica , Nanopartículas , Cobre , Germinação , Raízes de Plantas , Plântula
9.
Bull Environ Contam Toxicol ; 104(6): 770-777, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32328666

RESUMO

The increasing utilization of copper oxide nanoparticles (CuO NPs) and their release into the environment has made it imperative to elucidate their impact on the ecological system including plants. However, their potential toxic impact and mechanisms on plant growth are still unclear. The aim of this study was to investigate the effects of CuO NPs and released Cu ions on seed germination and early seedling growth, as well as physiological and biochemical parameters of Oryza sativa. The results showed that CuO NPs at high concentration significantly inhibited seed germination and early seedling growth. The toxicity of CuO NPs originated from the particulate NPs rather than the released Cu2+. The phytotoxicity of CuO NPs to rice seed germination and seedling growth probably induced by high Cu accumulation along with the lignification and oxidative damage. The work presented here will increase our knowledge of phytotoxicity of CuO NPs.


Assuntos
Cobre/toxicidade , Germinação/efeitos dos fármacos , Nanopartículas/toxicidade , Oryza/efeitos dos fármacos , Plântula/efeitos dos fármacos , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Bioacumulação , Cobre/metabolismo , Relação Dose-Resposta a Droga , Lignina/metabolismo , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Plântula/crescimento & desenvolvimento , Poluentes do Solo/metabolismo
10.
J Mater Chem B ; 8(8): 1739-1747, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32030386

RESUMO

Gold nanoclusters (AuNCs) with an ultra-small size, as new inorganic photosensitizers, have been shown to be promising in photodynamic therapy (PDT), but their application has been restricted due to short blood circulation. It is therefore important to develop stimuli-responsive AuNC-based nanoprobes to achieve highly efficient PDT. Here, metal-organic framework (MOF, ZIF-8) encapsulated AuNCs (AuNCs@MOF) were synthesized, and then they were loaded with doxorubicin (DOX) to obtain pH-responsive nanoprobes (AuNCs@MOF-DOX) with modulated release for enhanced PDT/chemotherapy. In an acidic tumor microenvironment, the structure of ZIF-8 collapsed, accelerating the release of the AuNCs and DOX in the tumor cells, and enhancing the performance of PDT/chemotherapy. Under irradiation with a 670 nm laser, a large amount of singlet oxygen was generated, and the release rate of DOX increased to 77.1% at a pH value of 5.5. By single PDT and single chemotherapy, the tumors were only partially inhibited, but they completely disappeared using the combination of PDT and chemotherapy. The prepared pH-responsive AuNCs@MOF-DOX nanoprobes with modulated release showed excellent PDT/chemotherapy performance, and will be important bi-functional nanoprobes for synergistic therapy.


Assuntos
Ouro/química , Estruturas Metalorgânicas/química , Nanoestruturas/química , Animais , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/metabolismo , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/uso terapêutico , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Feminino , Concentração de Íons de Hidrogênio , Lasers , Camundongos , Camundongos Nus , Fotoquimioterapia , Oxigênio Singlete/metabolismo , Transplante Homólogo
11.
Nanoscale ; 12(3): 1801-1810, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31898712

RESUMO

Black titanium dioxide (TiO2) nanoparticles have attracted great attention due to their application in photothermal therapy (PTT). However, single-mode phototherapy has the risk of recurrence, and the high-dose laser usually imposed to improve the PTT performance can bring a potential threat to security. Here, polydopamine (PDA)-coated black TiO2 (b-P25@PDA) nanoparticles with a core-shell structure were synthesized for enhanced PTT; then, synergistic phototherapy nanoprobes (b-P25@PDA-Ce6 (Mn)) were constructed by coupling chlorin e6 (Ce6) and chelating Mn2+ for simultaneous photodynamic therapy (PDT)/PTT and magnetic resonance (MR) imaging, in which a low-dose laser was used and imaging-guided phototherapy with high efficiency and high safety was achieved. The prepared nanoprobes showed high photothermal conversion efficiency (32.12%), high reactive oxygen generation and excellent MR imaging. In the 4T1 tumor-bearing nude mouse model, the tumors completely disappeared under the combination of PDT/PTT with a low-dose laser but were only partially inhibited by single PDT and single PTT. The current work developed a multifunctional black TiO2-based nanoprobe for enhanced synergistic PDT/PTT and MR imaging, which will be important for the safe and efficient visualized theranostics of cancers.


Assuntos
Meios de Contraste , Indóis , Imageamento por Ressonância Magnética , Neoplasias Mamárias Animais , Manganês , Nanopartículas , Fototerapia , Polímeros , Porfirinas , Titânio , Animais , Linhagem Celular Tumoral , Meios de Contraste/química , Meios de Contraste/farmacologia , Feminino , Indóis/química , Indóis/farmacologia , Neoplasias Mamárias Animais/diagnóstico por imagem , Neoplasias Mamárias Animais/tratamento farmacológico , Manganês/química , Manganês/farmacologia , Camundongos , Nanopartículas/química , Nanopartículas/uso terapêutico , Polímeros/química , Polímeros/farmacologia , Porfirinas/química , Porfirinas/farmacologia , Titânio/química , Titânio/farmacologia
12.
Nat Prod Res ; : 1-5, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31984779

RESUMO

We investigated the antioxidant activities of different solvent extracts of Angelica amurensis root (AAR). The yield of aqueous extract was the highest. The methanol extract had the highest total phenolic content and total flavonoid content. The aqueous extract showed the highest total carbohydrate content. Methanol and ethanol extracts showed high DPPH and ABTS radical-scavenging abilities, and high antioxidant activities in FRAP and CUPRAC assays. The extract of chloroform and water exhibited high ability to scavenge hydroxyl radicals. All extracts showed high inhibition of ß-carotene bleaching, ethyl acetate extract showed the best effect. Ethyl acetate extract exhibited the highest protection against cellular oxidative damage. The best extraction solvent for the active substance in AAR was methanol. AAR may act as a natural antioxidant.

13.
Adv Healthc Mater ; 9(1): e1900948, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31746549

RESUMO

Prussian blue nanoprobes are widely studied and applied in tumor photothermal therapy (PTT) and magnetic resonance imaging (MRI), due to their low toxicity and excellent in vivo performance. However, the sizes of hitherto reported Prussian blue nanoprobes are generally larger than 50 nm, which greatly influence cell phagocytosis, in vivo circulation, and biodistribution. In this work, a novel method of doping zinc ions is used to control the size of Prussian blue nanoprobes. Consequently, the performances of the nanoprobes in PTT and MRI are both significantly improved. The results show that the minimum size of Prussian blue nanoprobes achieved by doping 10% zinc ions (abbreviated as SPBZn(10%)) is 3.8 ± 0.90 nm, and the maximum specific absorption coefficient, photothermal conversion efficiency, and longitudinal relaxation rates are 1.78 L g-1 cm-1 , 47.33%, and 18.40 mm-1 s-1 , respectively. In addition, the SPBZn(10%) nanoprobes provide excellent PTT efficacy on 4T1 tumor cells (killing rate: 90.3%) and breast cancer model (tumor inhibition rate: 69.4%). Toxicological experiment results show that the SPBZn(n%) nanoprobes exhibit no obvious in vitro cytotoxicity and they can be used safely in mice at doses below 100 mg kg-1 . Therefore, SPBZn(10%) nanoprobes can potentially be used for effective cancer theranostics.


Assuntos
Neoplasias da Mama/terapia , Ferrocianetos/química , Nanoestruturas/química , Fármacos Fotossensibilizantes/química , Terapia Fototérmica/métodos , Zinco/química , Animais , Neoplasias da Mama/diagnóstico por imagem , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Hipertermia Induzida , Raios Infravermelhos , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Fármacos Fotossensibilizantes/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Nanomedicina Teranóstica , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Ecotoxicol Environ Saf ; 187: 109785, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31644988

RESUMO

The germination and seedling vigor of crops is negatively affected by soil salinity. Nitric oxide (NO) has emerged as a key molecule involved in many physiological events in plants. The objective of present study was to evaluate the impact of exogenous sodium nitroprusside (SNP, a NO donor) at different concentrations on the seed germination and early seedling growth characteristics of pakchoi (Brassica chinensis L.) under NaCl stress. 100 mM NaCl stress markedly inhibited the seed germination potential, germination index, vitality index and growth of radicles and plumules. SNP pretreatment attenuated the salt stress effects in a dose-dependent manner, as indicated by enhancing the characteristics of seed germination and early seedling growth parameters, and the mitigating effect was most pronounced at 10 µM SNP. Efficient antioxidant systems were activated by SNP pre-treatment, and which effectively increased the activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX), and reduced contents of malondialdehyde (MDA) and hydrogen peroxide (H2O2) and the production rate of superoxide anion radical (O2·-) in radicles and plumules, thereby preventing oxidative damage from NaCl stress. SNP pre-treatment also increased the contents of proline and soluble sugar in radicles and plumules under NaCl stress. In addition, SNP pre-treatment significantly increased the K+ contents and decreased Na+ contents in radicles and plumules, resulting in the increased level of K+/Na+ ratio. Our results demonstrated that SNP application on pakchoi seeds may be a good option to improve seed germination and seedling growth under NaCl stress by modulating the physiological responses resulting in better seed germination and seedling growth.


Assuntos
Brassica/efeitos dos fármacos , Germinação/efeitos dos fármacos , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico/farmacologia , Estresse Salino/efeitos dos fármacos , Antioxidantes/metabolismo , Brassica/crescimento & desenvolvimento , Brassica/metabolismo , Relação Dose-Resposta a Droga , Salinidade , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Sementes/efeitos dos fármacos , Sementes/fisiologia
15.
Adv Healthc Mater ; 7(24): e1801144, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30370656

RESUMO

Compared with other subtypes of breast cancer, triple-negative breast cancer (TNBC) is seriously threatening to human life. Therefore, it is a matter of urgency to develop multifunctional nanoprobes for visualized theranostics of TNBC, achieving specific targeting toward only TNBC, but not other subtypes. Nanoscale metal-organic frameworks (MOFs) show important potential in visualized theranostics of tumors, but it is critical to synthesize well-defined core-shell MOF-based nanocomposites by encapsulating a single nanoparticle within MOF. In this study, a TNBC-targeted peptide (ZD2)-engineered, and a single gold nanostar (AuNS) coated within MIL-101-NH2 (Fe) by coating MOF with four cycles, obtain well-defined core-shell AuNS@MOF-ZD2 nanocomposites, which are expected to achieve T1 -weighted magnetic resonance imaging and photothermal therapy (PTT) specifically targeting toward TNBC. The prepared AuNS@MOF-ZD2 nanocomposites possess good biocompatibility, efficient T1 -weighted magnetic resonance (MR) relaxivity and stable photothermal conversion ability with an efficiency of 40.5%. The in vitro and in vivo characterizations prove their performances of T1 -weighted MR and PTT with a low power density of 808 nm laser, achieving excellent theranostic efficacy in TNBC. Importantly, it is demonstrated that the prepared AuNS@MOF-ZD2 nanoprobes can specifically target TNBC cells (MDA-MB-231), but not other subtypes of breast cancer cells (MDA-MB-435, MDA-MB-468, and MCF-7), indicating their promising application in visualized theranostics of breast cancers with molecular classification.


Assuntos
Ouro/química , Estruturas Metalorgânicas/química , Nanocompostos/química , Peptídeos/química , Neoplasias de Mama Triplo Negativas/terapia , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/uso terapêutico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Hipotermia Induzida , Lasers , Imageamento por Ressonância Magnética , Camundongos , Camundongos Nus , Fototerapia , Nanomedicina Teranóstica , Transplante Heterólogo , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/patologia
16.
Small ; 14(35): e1801851, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30058139

RESUMO

AuroShell nanoparticles (sealed gold nanoshell on silica) are the only inorganic materials that are approved for clinical trial for photothermal ablation of solid tumors. Based on that, porous gold nanoshell structures are thus critical for cancer multiple theranostics in the future owing to their inherent cargo-loading ability. Nevertheless, adjusting the diverse experimental parameters of the reported procedures to obtain porous gold nanoshell structures is challenging. Herein, a series of amino-functionalized porous metal-organic frameworks (NH2 -MOFs) nanoparticles are uncovered as superior templates for porous gold nanoshell deposition (NH2 -MOFs@Aushell ) by means of a more facile and general one-step method, which combines the enriched functionalities of NH2 -MOFs with those of porous gold nanoshells. Moreover, in order to illustrate the promising applications of this method in biomedicine, platinum nanozymes-encapsulated NH2 -MOFs are further designed with porous gold nanoshell coating and photosensitizer chlorin e6 (Ce6)-loaded nanoparticles with continuous O2 -evolving ability (Pt@UiO-66-NH2 @Aushell -Ce6). The combination of photodynamic and photothermal therapy is then carried out both in vitro and in vivo, achieving excellent synergistic therapeutic outcomes. Therefore, this work not only presents a facile strategy to fabricate functionalized porous gold nanoshell structures, but also illustrates an excellent synergistic tumor therapy strategy.


Assuntos
Ouro/química , Estruturas Metalorgânicas/química , Nanoconchas/química , Neoplasias/terapia , Animais , Terapia Combinada , Humanos , Células MCF-7 , Estruturas Metalorgânicas/ultraestrutura , Camundongos , Nanoconchas/ultraestrutura , Porosidade , Temperatura
17.
ACS Chem Biol ; 13(4): 871-875, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29437374

RESUMO

An enoylreductase (ER) domain of a polyketide synthase module recruiting a methylmalonate extender unit sets the C2 methyl branch to either the S or R configuration during processing of a polyketide intermediate carried by an acyl carrier protein (ACP) domain. In the present study, pantetheine- and ACP-bound trans-2-methylcrotonyl substrate surrogates were used to scrutinize the stereospecificity of the ER domains. The pantetheine-bound thioester was reduced to mixtures of both 2 R and 2 S products, whereas the expected 2 S epimer was almost exclusively generated when the cognate ACP-bound substrate surrogate was utilized. The analogous incubation of an ER with the substrate surrogate carried by a noncognate ACP significantly increased the generation of the unexpected 2 R epimer, highlighting the dependence of stereospecificity on proper protein-protein interactions between ER and ACP domains. The ER mutant assays revealed the involvement of the conserved tyrosine and lysine in stereocontrol. Taken together, these results expand the current understanding of the ER stereochemistry and help in the engineering of modular PKSs.


Assuntos
Policetídeo Sintases/química , Proteína de Transporte de Acila , Domínio Catalítico , Engenharia de Proteínas/métodos , Estereoisomerismo , Especificidade por Substrato
18.
Water Sci Technol ; 68(6): 1251-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24056420

RESUMO

The sorption of chloramphenicol on four types of sediment and the effect of coexistence Cu(II) on the sorption were studied. Sorption isotherms and thermodynamic analysis were employed to dispose the experimental sorption data. Experimental results showed that organic matter was the dominant parameter and the coexistence of heavy metal Cu(II) could promote the sorption of chloramphenicol on four tested sediments. The adsorption parameter analysis showed sorption of chloramphenicol on the sediment was not pure distributional effects, not a strong interaction between molecule and surface, but other weak interactions. Thermodynamic parameters values such as ΔG, ΔH and ΔS were all below zero, which indicated that the sorption was a spontaneous and exothermal process.


Assuntos
Cloranfenicol/química , Cobre/química , Sedimentos Geológicos/química , Poluentes Químicos da Água/química , Adsorção , Lagoas , Temperatura
19.
Bioorg Med Chem Lett ; 21(19): 5722-5, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21885274

RESUMO

5-Isoproyl-3,8-dimethylazulene derivatives were synthesized and evaluated for antigastric ulcer activity in vivo. Some of them possess the best activity against gastric ulcer with ulcer index values lower than the drug reference (omeprazole). The structure-activity relationship (SAR) shows that the lipophilic flat structure contributes to quite potent antigastric ulcer activity.


Assuntos
Antiulcerosos/síntese química , Antiulcerosos/farmacologia , Azulenos/síntese química , Desenho de Fármacos , Descoberta de Drogas , Sulfonamidas/síntese química , Animais , Antiulcerosos/química , Azulenos/química , Azulenos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Camundongos , Estrutura Molecular , Úlcera Gástrica/tratamento farmacológico , Relação Estrutura-Atividade , Sulfonamidas/química , Sulfonamidas/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...