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1.
Small ; 19(10): e2207517, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36650989

RESUMO

Aqueous rechargeable zinc-ion batteries (ZIBs) have attracted burgeoning interests owing to the prospect in large-scale and safe energy storage application. Although manganese oxides are one of the typical cathodes of ZIBs, their practical usage is still hindered by poor service life and rate performance. Here, a MnO2 -carbon hybrid framework is reported, which is obtained in a reaction between the dimethylimidazole ligand from a rational designed MOF array and potassium permanganate, achieving ultralong-cycle-life ZIBs. The unique structural feature of uniform MnO2 nanocrystals which are well-distributed in the carbon matrix leads to a 90.4% capacity retention after 50 000 cycles. In situ characterization and theoretical calculations verify the co-ions intercalation with boosted reaction kinetics. The hybridization between MnO2 and carbon endows the hybrid with enhanced electrons/ions transport kinetics and robust structural stability. This work provides a facile strategy to enhance the battery performance of manganese oxide-based ZIBs.

2.
Chem Rec ; 22(10): e202200079, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35635378

RESUMO

Aqueous rechargeable zinc-ion batteries (ZIBs) featuring competitive performance, low cost and high safety hold great promise for applications in grid-scale energy storage and portable electronic devices. Metal-organic frameworks (MOFs), relying on their large framework structure and abundant active sites, have been identified as promising materials in ZIBs. This review comprehensively presents the current development of MOF-based materials including MOFs and their derivatives in ZIBs, which begins with Zn storage mechanism of MOFs, followed by introduction of various types of MOF-based cathode materials (PB and PBA, Mn-based MOF, V-based MOF, conductive MOF and their derivatives), and the regulation approaches for Zn deposition behavior. The key factors and optimization strategies of MOF-based materials that affect ZIBs performance are emphasized and discussed. Finally, the challenges and further research directions of MOF-based materials for advanced zinc-ion batteries are provided.

3.
Small ; 17(33): e2101901, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34228384

RESUMO

Although aqueous Zn-ion batteries (ZIBs) with low cost and high safety show great potential in large-scale energy storage system, metallic Zn anode still suffers from unsatisfactory cycle stability due to unregulated growth of Zn dendrites, corrosion, and formation of various side products during electrochemical reaction. Here, an ultrafast and simple method to achieve a stable Zn anode is developed. By simply immersing a Zn plate into an aqueous solution of CuSO4 for only 10-60 s, a uniform and robust protective layer (Zn4 SO4 (OH)6 ·5H2 O/Cu2 O) is formed on commercial Zn plate (Zn/ZCO), which enables uniform electric field distribution and controllable dendrite growth, leading to a long-term cycle life of over 1400 h and high average Coulombic efficiency (CE) of 99.2% at 2.0 mA cm-2 and 2.0 mAh cm-2 . These excellent characteristics of the prepared Zn anode show great potential in practical applications for high-performance aqueous Zn-ion batteries.

4.
BMC Cancer ; 21(1): 664, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34082742

RESUMO

BACKGROUND: Fenofibrate is a fibric acid derivative known to have a lipid-lowering effect. Although fenofibrate-induced peroxisome proliferator-activated receptor alpha (PPARα) transcription activation has been shown to play an important role in the malignant progression of gliomas, the underlying mechanisms are poorly understood. METHODS: In this study, we analyzed TCGA database and found that there was a significant negative correlation between the long noncoding RNA (lncRNA) HOTAIR and PPARα. Then, we explored the molecular mechanism by which lncRNA HOTAIR regulates PPARα in cell lines in vitro and in a nude mouse glioma model in vivo and explored the effect of the combined application of HOTAIR knockdown and fenofibrate treatment on glioma invasion. RESULTS: For the first time, it was shown that after knockdown of the expression of HOTAIR in gliomas, the expression of PPARα was significantly upregulated, and the invasion and proliferation ability of gliomas were obviously inhibited. Then, glioma cells were treated with both the PPARα agonist fenofibrate and si-HOTAIR, and the results showed that the proliferation and invasion of glioma cells were significantly inhibited. CONCLUSIONS: Our results suggest that HOTAIR can negatively regulate the expression of PPARα and that the combination of fenofibrate and si-HOTAIR treatment can significantly inhibit the progression of gliomas. This introduces new ideas for the treatment of gliomas.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Fenofibrato/farmacologia , Glioma/tratamento farmacológico , RNA Longo não Codificante/antagonistas & inibidores , RNA Interferente Pequeno/farmacologia , Adulto , Idoso , Animais , Encéfalo/patologia , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sequenciamento de Cromatina por Imunoprecipitação , Feminino , Fenofibrato/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/diagnóstico , Glioma/genética , Glioma/patologia , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Gradação de Tumores , PPAR alfa/genética , RNA Longo não Codificante/genética , RNA Interferente Pequeno/uso terapêutico , Técnicas Estereotáxicas , Ativação Transcricional/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
Nanotechnology ; 33(2)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34619665

RESUMO

Constructing sophisticated hollow structure and exposing more metal sites in metal-organic frameworks (MOFs) can not only enhance their catalytic performance but also endow them with new functions. Herein, we present a facile coordinative reconstruction strategy to transform Ti-MOF polyhedron into nanosheet-assembled hollow structure with a large amount of exposed metal sites. Importantly, the reconstruction process relies on the esterification reaction between the organic solvent, i.e. ethanol and the carboxylic acid ligand, allowing the conversion of MOF without the addition of any other modulators and/or surfactants. Moreover, the surface and internal structure of the reconstructed MOF can be well tuned via altering the conversion time. Impressively, the reconstructed MOF exhibits ∼5.1-fold rate constant compared to the pristine one in an important desulfurization reaction for clean fuels production, i.e. the oxidation of dibenzothiophene.

6.
Int J Immunogenet ; 46(6): 451-458, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31342644

RESUMO

DNA mismatch repair (MMR) plays a critical role in the maintenance of genetic integrity. The failure of MMR in sperm DNA was found in male infertility. However, its aetiology in idiopathic male infertility (IMI) remains unknown. The present study was to investigate whether the four SNPs (rs26279 in MSH3, rs1800734 and rs4647269 in MLH1 and rs175080 in MLH3) in MMR genes were associated with IMI or not. The interactions of the SNPs were also performed to clarify its genetic aetiology. In the present study, 209 clinically diagnosed IMI men and 201 fertile men were recruited. Four SNPs were genotyped by DNA sequencing. It was the first time to investigate the association between rs26279 in MSH3 and IMI. The genotype frequency distribution of rs26279 (A>G) in MSH3 was found to be significantly different between IMI and control (p < 0.05), as well as azoospermia. The rs1800734 and rs4647269 in MLH1 were found to be significantly different between severe oligozoospermia and control groups (p < 0.05). However, rs175080 in MLH3 was not significantly different between IMI and control (p > 0.05). Multifactor dimensionality reduction (MDR) for detecting interactions showed that there were no interactions among the four SNPs on IMI.


Assuntos
Infertilidade Masculina/genética , Proteína 1 Homóloga a MutL/genética , Proteínas MutL/genética , Proteína 3 Homóloga a MutS/genética , Polimorfismo de Nucleotídeo Único , Alelos , Estudos de Casos e Controles , China , Dano ao DNA , Reparo de Erro de Pareamento de DNA , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino
7.
Mol Med ; 21(1): 959-968, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26736177

RESUMO

Extensively burned patients often suffer from sepsis, a complication that enhances postburn hypermetabolism and contributes to increased incidence of multiple organ failure, morbidity and mortality. Despite the clinical importance of burn sepsis, the molecular and cellular mechanisms of such infection-related metabolic derangements and organ dysfunction are still largely unknown. We recently found that upon endoplasmic reticulum (ER) stress, the white adipose tissue (WAT) interacts with the liver via inflammatory and metabolic signals leading to profound hepatic alterations, including hepatocyte apoptosis and hepatic fatty infiltration. We therefore hypothesized that burn plus infection causes an increase in lipolysis of WAT after major burn, partially through induction of ER stress, contributing to hyperlipidemia and profound hepatic lipid infiltration. We used a two-hit rat model of 60% total body surface area scald burn, followed by intraperitoneal (IP) injection of Pseudomonas Aeruginosa-derived lipopolysaccharide (LPS) 3 d postburn. One day later, animals were euthanized and liver and epididymal WAT (EWAT) samples were collected for gene expression, protein analysis and histological study of inflammasome activation, ER stress, apoptosis and lipid metabolism. Our results showed that burn plus LPS profoundly increased lipolysis in WAT associated with significantly increased hepatic lipid infiltration. Burn plus LPS augmented ER stress by upregulating CHOP and activating ATF6, inducing NLRP3 inflammasome activation and leading to increased apoptosis and lipolysis in WAT with a distinct enzymatic mechanism related to inhibition of AMPK signaling. In conclusion, burn sepsis causes profound alterations in WAT and liver that are associated with changes in organ function and structure.

8.
Eur J Neurosci ; 39(4): 531-47, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24236816

RESUMO

Dlx1, a member of the homeobox domain transcriptional factors, is expressed in a subset of interneurons and is involved in their differentiation. To understand the roles of Dlx1 in dendritic and postsynaptic differentiation, we manipulated Dlx1 expression in both excitatory pyramidal neurons and inhibitory interneurons in hippocampal culture. Exogenous expression of Dlx1 in pyramidal neurons, which lack endogenous Dlx1, resulted in reduced complexity of dendritic arborization. This effect was dependent on the DNA-binding motif of Dlx1. Dlx1 overexpression also induced prominent reduction of spine density, but with mild suppression in the formation of postsynaptic densities. To confirm the roles of endogenous Dlx1, we knocked down Dlx1 in interneurons and found enhanced dendritic growth. By manipulating the expression of possible downstream effectors of Dlx1, neuropilin-2 and p21-activated kinase 3, we provided evidence for the involvement of these two signaling molecules in Dlx1-dependent regulation of dendritic differentiation. Our experimental data support the idea that Dlx1 expression in developing interneurons specifically suppresses two important downstream regulators, leading to the characteristic morphology of Dlx1-expressing interneurons with less branched dendrites and few dendritic spines.


Assuntos
Dendritos/metabolismo , Proteínas de Homeodomínio/metabolismo , Neurogênese , Neuropilina-2/metabolismo , Densidade Pós-Sináptica/metabolismo , Fatores de Transcrição/metabolismo , Quinases Ativadas por p21/metabolismo , Animais , Células Cultivadas , Dendritos/fisiologia , Hipocampo/citologia , Hipocampo/crescimento & desenvolvimento , Proteínas de Homeodomínio/genética , Interneurônios/citologia , Interneurônios/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Neuropilina-2/genética , Células Piramidais/citologia , Células Piramidais/metabolismo , Fatores de Transcrição/genética , Quinases Ativadas por p21/genética
9.
Br J Hosp Med (Lond) ; 85(5): 1-5, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38815966

RESUMO

A low-protein diet (LPD) has become an important way to delay the progression of chronic kidney disease (CKD) and to delay the need for dialysis. A review of the literature reveals the low-protein diet's influence on the course of chronic kidney disease. An artificial low-protein food, wheat starch, for example, can not only increase the high-quality protein intake ratio, but can ensure adequate energy intake on a low-protein diet while meeting the nutritional needs of the body, effectively reducing the burden on the damaged kidneys. The purpose of this review is to provide a reference for the clinical implementation of diet and nutrition therapy in patients with chronic kidney disease.


Assuntos
Dieta com Restrição de Proteínas , Progressão da Doença , Insuficiência Renal Crônica , Humanos , Dieta com Restrição de Proteínas/métodos , Insuficiência Renal Crônica/dietoterapia , Insuficiência Renal Crônica/terapia , Proteínas Alimentares/administração & dosagem
10.
ACS Appl Mater Interfaces ; 15(35): 41476-41482, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37625012

RESUMO

Developing highly active and robust oxygen catalysts is of great significance for the commercialization of Zn-air batteries (ZABs) with long-life stability. Herein, heterostructured catalysts comprising molybdenum carbide and metallic Co are prepared by a simple dicyandiamide-assisted pyrolysis strategy. Importantly, the crystalline phase of molybdenum carbide in the catalysts can be carefully regulated by adjusting the CoMo-imidazole precursor and dicyandiamide ratio. The electronic configuration of Co and Mo centers as well as the phase-dependent oxygen reduction reaction performance of these heterostructures (ß-Mo2C/Co, ß-Mo2C/η-MoC/Co, and η-MoC/Co) was disclosed. A highly active η-MoC/Co cathode enables ZABs with outstanding long-term stability over 850 h with a low voltage decaying rate of 0.06 mV·h-1 and high peak power density of 162 mW·cm-2. This work provides a new idea for the rational design of efficient and stable cathode catalysts for ZABs.

11.
Basic Res Cardiol ; 107(2): 241, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22231674

RESUMO

We have previously shown that remote ischemic preconditioning by limb ischemia (rIPC) or intra-arterial adenosine releases a dialyzable cardioprotective circulating factor(s), the release of which requires an intact neural connection to the limb and is blocked by pretreatment with S-nitroso-N-acetylpenicillamine (SNAP). Remote cardioprotection can be induced by other forms of peripheral stimulation including topical capsaicin, but the mechanisms of their signal transduction are incompletely understood. Rabbits were anesthetized by intravenous pentobarbital, intubated and ventilated, then randomized (4-7 animals in each group) to receive sham procedure, rIPC (4 cycles of 5 min lower limb ischemia, 5 min reperfusion), direct femoral nerve stimulation, topical capsaicin, pretreatment with intra-arterial SNAP + capsaicin, pretreatment with topical DMSO (a sensory nerve blocker) + topical capsaicin, or pretreatment with intra-arterial SNAP + femoral nerve stimulation, topical DMSO alone, or intra-arterial SNAP alone. Blood was then rapidly drawn from the carotid artery to produce the plasma dialysate which was used to perfuse a naïve heart from an untreated donor rabbit. The infarct size and recovery of LV-developed pressure and end-diastolic pressure were measured after 30 min of global ischemia and 120 min of reperfusion. Compared to sham, dialysate from rIPC, femoral nerve stimulation, and topical capsaicin groups all produced significant cardioprotection with significantly reduced infarct size, and improved the post-ischemic cardiac performance. Cardioprotection was not seen in the topical DMSO-capsaicin, SNAP + capsaicin, and SNAP + FNS groups. These results confirm the central role of peripheral nerves in the local signal transduction of remote cardioprotection. Direct electrical or peripheral neural stimulation evokes the release of cardioprotective substances into the bloodstream, with comparable effects to that of rIPC induced by limb ischemia.


Assuntos
Capsaicina/administração & dosagem , Precondicionamento Isquêmico/métodos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Sistema Nervoso Periférico/efeitos dos fármacos , Animais , Nervo Femoral/fisiologia , Hemodinâmica , Precondicionamento Isquêmico Miocárdico/métodos , Sistema Nervoso Periférico/fisiologia , Coelhos
12.
Int J Biol Macromol ; 214: 312-323, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35714869

RESUMO

Type 2 diabetes mellitus is a global disease that endangers human health, and the need for the development of nontoxic treatment candidates is urgent. In the present work, one homogeneous polysaccharide from Inonotus obliquus (IN) was isolated, and the protective effect and mechanism of IN on type 2 diabetes mellitus were investigated from the aspects of the intestinal barrier. IN mainly consisted of 9 monosaccharides with a Mw of 373 kDa. IN attenuated body weight loss, alleviated pathological damage, and suppressed the production of proinflammatory cytokines. Additionally, IN repaired the intestinal barrier by upregulating the expression of Ki-67, ZO-1 and MUC2. Furthermore, the abundance of Firmicutes was significantly increased with IN treatment, while the levels of Bacteroidetes were significantly inhibited. In conclusion, IN protected against type 2 diabetes mellitus by ameliorating intestinal barrier dysfunction and might serve as a novel drug candidate for type 2 diabetes mellitus.


Assuntos
Basidiomycota , Diabetes Mellitus Tipo 2 , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Carboidratos da Dieta , Humanos , Inonotus , Camundongos , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico
13.
Molecules ; 16(3): 2551-60, 2011 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-21441860

RESUMO

The traditional methods used in natural product separation primarily target the major components and the minor components may thus be lost during the separation procedure. Consequently, it's necessary to develop efficient methods for the preparative separation and purification of relatively minor bioactive components. In this paper, a LC/MS method was applied to guide the separation of crude extract of lotus (Nelumbo nucifera Gaertn.) leaves whereby a minor component was identified in the LC/MS analysis. Afterwards, an optimized pH-zone-refining CCC method was performed to isolate this product, identified as N-demethylarmepavine. The separation procedure was carried out with a biphasic solvent system composed of hexane-ethyl acetate-methyl alcohol-water (1:6:1:6, v/v) with triethylamine (10 mM) added to the upper organic phase as a retainer and hydrochloric acid (5 mM) to the aqueous mobile phase eluent. Two structurally similar compounds--nuciferine and roemerine--were also obtained from the crude lotus leaves extract. In total 500 mg of crude extract furnished 7.4 mg of N-demethylarmepavine, 45.3 mg of nuciferine and 26.6 mg of roemerine with purities of 90%, 92% and 96%, respectively. Their structures were further identified by HPLC/ESI-MSn, FTICR/MS and the comparison with reference compounds.


Assuntos
Alcaloides/isolamento & purificação , Cromatografia Líquida/métodos , Distribuição Contracorrente/métodos , Espectrometria de Massas/métodos , Folhas de Planta/química , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio
14.
Regen Med ; 16(4): 373-390, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33787319

RESUMO

Numerous individuals suffer from impaired wound healing, such as chronic ulcers, severe burns and immune disorders, resulting in both public health and economic burdens. Skin is the first line of defense and the largest organ of the human body, however, an incomplete understanding of underlying cellular and molecular mechanisms of dermal repair leads to a lack of effective therapy for healing impaired wounds. There are strong clinical and social needs for improved therapeutic approaches to enhance endogenous tissue repair and regenerative capacity. The purpose of this review is to illuminate the cellular and molecular aspects of the healing process and highlight potential therapeutic strategies to accelerate translational research and the development of clinical therapies in dermal wounds.


Assuntos
Queimaduras , Cicatrização , Humanos , Pele
15.
Am J Physiol Heart Circ Physiol ; 299(5): H1598-603, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20802131

RESUMO

We have previously shown that remote ischemic preconditioning (rIPC) by transient limb ischemia leads to the release of a circulating factor(s) that induces potent myocardial protection. Intra-arterial injection of adenosine into a limb also leads to cardioprotection, but the mechanism of its signal transduction is poorly understood. Eleven groups of rabbits received saline control or rIPC or adenosine administration with additional pretreatment with the nitric oxide (NO) synthase blocker N(G)-nitro-l-arginine methyl ester, the NO donor S-nitroso-N-acetylpenicillamine, its non-NO-donating derivative N-acetylpenicillamine, or femoral nerve section. Blood was then drawn from each animal, and the dialysate of the plasma was used to perfuse a naïve heart from an untreated donor. Infarct size was measured after 30 min of global ischemia and 120 min reperfusion. When compared with that of the control, mean infarct size was significantly smaller in groups treated with rIPC alone (P < 0.01) and intra-arterial adenosine (P < 0.01). Pretreatment with N(G)-nitro-l-arginine methyl ester or N-acetylpenicillamine did not affect the level of protection induced by rIPC (P = not significant, compared with rIPC alone) or intra-arterial adenosine (P = not significant, compared with intra-arterial adenosine alone), but prior femoral nerve transection or pretreatment with S-nitroso-N-acetylpenicillamine abolished the cardioprotective effect of intra-arterial adenosine and rIPC. Intra-arterial adenosine, like rIPC, releases a blood-borne cardioprotective factor(s) that is dependent on an intact femoral nerve and is inhibited by pretreatment with a NO donor. These results may be important when designing or assessing the results of clinical trials of adenosine or rIPC cardioprotection, where NO donors are used as part of therapy.


Assuntos
Adenosina/farmacologia , Nervo Femoral/cirurgia , Membro Posterior/irrigação sanguínea , Isquemia/metabolismo , Precondicionamento Isquêmico , Doadores de Óxido Nítrico/farmacologia , S-Nitroso-N-Acetilpenicilamina/farmacologia , Adenosina/administração & dosagem , Animais , Inibidores Enzimáticos/farmacologia , Membro Posterior/inervação , Injeções Intra-Arteriais , Masculino , Modelos Animais , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Coelhos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
16.
J Sep Sci ; 33(11): 1595-603, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20405489

RESUMO

In this paper, an effective method combing fast elution-extrusion counter-current chromatography (CCC) and LC/MS for rapid screening of antioxidative phenolic compounds in Chinese Rhubarb is presented. An integrated three-coil CCC column (40 mL each coil) was used to accomplish the optimization of biphasic liquid system. In a single run (approximately 40 min), the solvent system composed of n-hexane/ethyl acetate/methanol/water (1:1:1:1, v/v) was selected as optimum CCC liquid system for fast fractionation of the crude ethanol extract. With a 140 mL-capacity CCC instrument, 100 mg Chinese Rhubarb extract was separated under the optimized conditions, producing six fractions in only 100 min. The quantities of each fraction were approximately 15 mg. In addition, each fraction was subjected to antioxidant activity assay and characterized by LC/MS analysis. Fifty compounds, including phenolic acids, phenolic glucosides and hydroxyanthraquinones, were detected by LC/MS/MS analysis. As a result, gallic acid together with Fr I showed excellent antioxidant activity, which was well consistent with previous studies and exhibited great potential for natural drug discovery program of the present method.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Extratos Vegetais/análise , Rheum/metabolismo , Antioxidantes/química , Técnicas de Química Analítica , Cromatografia Líquida de Alta Pressão , Glucosídeos/química , Concentração Inibidora 50 , Metanol/química , Fenol/química , Solventes/química , Fatores de Tempo
17.
J Chromatogr A ; 1208(1-2): 42-6, 2008 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-18774575

RESUMO

An ionic liquid-based microwave-assisted extraction (ILMAE) approach has been successfully applied to the effective extraction of the phenolic alkaloids present in samples of the medicinal plant Nelumbo nucifera Gaertn. The ionic liquids investigated comprised a range of four anions, four 1-alkyl-3-methylimidazolium derivatives differing in hydrophobic chain length. The results indicate that varying the anion has apparent effects on the overall extraction efficiency. In addition, the influence of some microwave parameters, such as irradiation power, extraction time and solid-liquid ratio, are also investigated. Under the optimized conditions, the proposed approach has been evaluated in comparison with the conventional heat-reflux extraction (HRE) and regular MAE. The reduction of the extraction times (from 2h to 90s) and remarkable higher efficiency (20-50% improved) supports the suitability of the proposed approach. In addition, the proposed method is validated by the recovery, correlation coefficient (R(2)), and reproducibility (RSD, n=5), which are in the range of 98-105%, 0.9994-0.9998, and 1.2-5.4%, respectively.


Assuntos
Alcaloides/isolamento & purificação , Métodos Analíticos de Preparação de Amostras , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/isolamento & purificação , Nelumbo/química , Medicamentos de Ervas Chinesas/química , Líquidos Iônicos , Plantas Medicinais/química
18.
Chemosphere ; 72(7): 1020-6, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18504054

RESUMO

The goal of this study was to develop transgenic plants with increased tolerance for and accumulation of heavy metals and metalloids from soil by simultaneous overexpression of AsPCS1 and GSH1 (derived from garlic and baker's yeast) in Arabidopsis thaliana. Phytochelatins (PCs) and glutathione (GSH) are the main binding peptides involved in chelating heavy metal ions in plants and other living organisms. Single-gene transgenic lines had higher tolerance to and accumulated more Cd and As than wild-type. Compared to single-gene transgenic lines, dual-gene transformants exhibited significantly higher tolerance to and accumulated more Cd and As. One of the dual-gene transgenic lines, PG1, accumulated twice the amount of Cd as single-gene transgenic lines. Simultaneous overexpression of AsPCS1 and GSH1 led to elevated total PC production in transgenic Arabidopsis. These results indicate that such a stacking of modified genes is capable of increasing Cd and As tolerance and accumulation in transgenic lines, and represents a highly promising new tool for use in phytoremediation efforts.


Assuntos
Aminoaciltransferases/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Arsênio/metabolismo , Cádmio/metabolismo , Glutamato-Cisteína Ligase/metabolismo , Aminoaciltransferases/genética , Arabidopsis/efeitos dos fármacos , Arsênio/toxicidade , Biodegradação Ambiental , Cádmio/toxicidade , Alho/enzimologia , Expressão Gênica , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Glutamato-Cisteína Ligase/genética , Homeostase , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas , Saccharomyces cerevisiae/enzimologia , Fatores de Tempo
19.
Curr Med Sci ; 38(5): 809-817, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30594980

RESUMO

Osteosarcoma is the most common primary malignant bone tumor in childhood, and it maintains a high level of recurrence. Matrix metalloproteinase-1 (MMP-1) was found to contribute to cancer progression. The present study was to investigate the in vitro effects of MMP-1 over-expression on the proliferation, invasion, metastasis and stem-like properties of osteosarcoma MG-63 cells. The MG-63 cells were cultured and had a full length MMP-1 cDNA inserted by the lentiviral vector (MG-63MMP-1+). MG-63 negative control and MG-63 blank control groups were established as well. MMP-1 expression was detected in MG-63MMP-1+, MG-63 negative control and MG-63 blank control cells using qPCR, Western blotting and immunofluorescence after 24 h of culture. The cell proliferation assay was performed with a camera attached to a bioreactor, which was programmed to photograph five regions of each well every 10 min over a period of 48 h. The cell invasion assay was conducted with Matrigel to assess the invasive potential of MG-63 cells over 24 h, the qPCR analysis to measure stem cell markers, including Oct4, Sox-2, Nanog, and Pax-7, and Western blot analysis to detect invasive and metastatic potential markers TIMP-1, VEGF and BMP2/4, after 24 h of culture. Immunofluorescence was used to investigate the presence of the stem cell marker Pax-7 after 24-h culture. The results showed that over-expression of MMP-1 after transfection could significantly increase tumor cell proliferation and invasion (P<0.05, MG-63MMP-1+versus controls). Pax-7 was highly expressed in MG-63MMP-1+ cells, with no significant changes of Oct-4, Sox-2, and Nanog observed (P<0.05). MG-63MMP-1+ cells showed higher expression of VEGF and BMP 2/4 proteins and lower expression of TIMP-1 protein than controls (P<0.05). It was concluded that MMP-1 over-expression in MG-63 cells contributed to the proliferation, invasion, metastasis and stem-like properties of osteosarcoma cells. Future studies should focus on in vivo effects of MMP-1 over-expression and the application of MMP-1 and Pax-7 inhibition in vivo to osteosarcoma therapies.


Assuntos
Neoplasias Ósseas/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Osteossarcoma/metabolismo , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Humanos , Invasividade Neoplásica/patologia , Osteossarcoma/patologia , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
20.
Circulation ; 114(21): 2271-9, 2006 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-17088456

RESUMO

BACKGROUND: Although numerous signaling pathways are known to be activated in experimental cardiac hypertrophy, the molecular basis of the hypertrophic response inherent in human heart diseases remains largely unknown. Integrin-linked kinase (ILK) is a multifunctional protein kinase that physically links beta-integrins with the actin cytoskeleton, suggesting a potential mechanoreceptor role. METHODS AND RESULTS: Here, we show a marked increase in ILK protein levels in hypertrophic ventricles of patients with congenital and acquired outflow tract obstruction. This increase in ILK was associated with activation of the Rho family guanine triphosphatases, Rac1 and Cdc42, and known hypertrophic signaling kinases, including extracellular signal-related kinases (ERK1/2) and p70 S6 kinase. Transgenic mice with cardiac-specific expression of a constitutively active ILK (ILK(S343D)) or wild-type ILK (ILK(WT)) exhibited a compensated ventricular hypertrophic phenotype and displayed an activation profile of guanine triphosphatases and downstream protein kinases concordant with that seen in human hypertrophy. In contrast, transgenic mice with cardiomyocyte-restricted expression of a kinase-inactive ILK (ILK(R211A)) were unable to mount a compensatory hypertrophic response to angiotensin II in vivo. CONCLUSIONS: Taken together, these results identify ILK-regulated signaling as a broadly adaptive hypertrophic response mechanism relevant to a wide range of clinical heart disease.


Assuntos
Cardiomegalia/enzimologia , Cardiomegalia/etiologia , Proteínas Serina-Treonina Quinases/metabolismo , Alanina , Angiotensina II , Animais , Arginina , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feto/enzimologia , Ventrículos do Coração , Humanos , Lactente , Camundongos , Camundongos Transgênicos , Mutação , Miocárdio/enzimologia , Miócitos Cardíacos/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Obstrução do Fluxo Ventricular Externo/congênito , Obstrução do Fluxo Ventricular Externo/enzimologia , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
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