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1.
Small ; 20(8): e2306111, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37821411

RESUMO

Aqueous zinc ion battery (AZIBs) has attracted the attention of many researchers because of its safety, economy, environmental protection, and high ionic conductivity of electrolytes. However, the battery greatly suffers from zinc dendrite produced by zinc metal anode leading to poor cycle life and even unsafe problems, which limit its further development for various important applications. It is known that the success of the commercialization of lithium-ion batteries (LIBs) is mainly due to replacement of lithium metal anode with graphite, which avoids the formation of Li dendrite. Therefore, it is an important step to develop aqueous zinc ion anode to replace conventional zinc metal one with zinc-metal free anode material. In this review, the working principle and development prospect of "rocking-chair" AZIBs are introduced. The research progress of different types of zinc metal-free anode materials and cathode materials in "rocking-chair" AZIBs is reviewed. Finally, the limitations and challenges of the Zn metal-free "rocking-chair" AZIBs as well as solutions are deeply discussed, aiming to provide new strategies for the development of advanced zinc-ion batteries.

2.
Small ; 19(35): e2300467, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37127871

RESUMO

Ni(OH)2 nanosheet, acting as a potential active material for supercapacitors, commonly suffers from sluggish reaction kinetics and low intrinsic conductivity, which results in suboptimal energy density and long cycle life. Herein, a convenient electrochemical halogen functionalization strategy is applied for the preparation of mono/bihalogen engineered Ni(OH)2 electrode materials. The theoretical calculations and experimental results found that thanks to the extraordinarily high electronegativity, optimal reversibility, electronic conductivity, and reaction kinetics could be achieved through F functionalization . However, benefiting from the largest ionic radius, INi(OH)2 contributes the best specific capacity and morphology transformation, which is a new finding that distinguishes it from previous reports in the literature. The exploration of the interaction effect of halogens (F, INi(OH)2 , F, BrNi(OH)2 , and Cl, INi(OH)2 ) manifests that F, INi(OH)2 delivers a higher specific capacity of 200.6 mAh g-1 and an excellent rate capability of 58.2% due to the weaker electrostatic repulsion, abundant defect structure, and large layer spacing. Moreover, the F, INi(OH)2 //FeOOH@NrGO device achieves a high energy density of 97.4 Wh kg-1 and an extremely high power density of 32426.7 W kg-1 , as well as good cycling stability. This work develops a pioneering tactic for designing energy storage materials to meet various demands.

3.
Zhongguo Zhong Yao Za Zhi ; 47(23): 6466-6475, 2022 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-36604893

RESUMO

The present study aimed to explore the targets and mechanism of Mailuo Shutong Pills(MSP) in the treatment of ischemic stroke by network pharmacology, and verify the key targets through molecular docking and animal experiment, so as to provide a theoretical basis for the clinical application of MSP. The main chemical ingredients of MSP were obtained by searching against the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP) and relevant literature. The potential targets of the ingredients of MSP in treating ischemic stroke were obtained from SwissTargetPrediction and DisGeNET. Protein-protein interaction(PPI) network was analyzed in STRING and plotted in Cytoscape. Gene Ontology(GO) annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment analysis were carried out with DAVID. Molecular docking was simulated to determine the binding activity of active ingredients to key targets in AutoDock Vina. The mouse model of ischemic stroke was established. The mice were classified into a sham group, a model group, and an MSP group. After the administration, cerebral infarction volume was detected by 2,3,5-triphenyltetrazoliumchloride(TTC) staining, and Western blot was performed to determine the levels of phosphatidylinositol 3-kinase(PI3 K), protein kinase B(AKT), nuclear factor-κB(NF-κB) and their phosphorylated proteins. A total of 222 ingredients of MSP were screened out, including beta-sitosterol, quercetin, licochalcone B, and lupiwighteone, which acted on 701 targets. Totally 1 079 targets associated with ischemic stroke were retrieved, among which 192 common targets were shared by MSP and ischemic stroke. The key targets included AKT1, phosphatidylinositol 3-kinase catalytic subunit alpha(PIK3 CA), phosphatidylinositol 3-kinase regulatory subunit 1(PIK3 R1), and nuclear factor-κB p65 subunit(RELA), which were mainly involved in PI3 K/AKT, tumor necrosis factor(TNF), and NF-κB signaling pathways. The results of molecular docking revealed that PI3 K, AKT1, and RELA had good binding ability to the active ingredients of MSP. The animal experiment results showed that compared with the model group, MSP decreased cerebral infarction volume, down-regulated the expression of p-NF-κB, and up-regulated the expression of p-PI3 K and p-AKT in mouse brain. In summary, the active ingredients in MSP may treat cerebral injury by activating PI3 K/AKT signaling pathway and inhibiting NF-κB signaling pathway.


Assuntos
Medicamentos de Ervas Chinesas , AVC Isquêmico , Animais , Camundongos , NF-kappa B/genética , Proteínas Proto-Oncogênicas c-akt/genética , AVC Isquêmico/tratamento farmacológico , Simulação de Acoplamento Molecular , Fosfatidilinositol 3-Quinases/genética , Infarto Cerebral , Medicamentos de Ervas Chinesas/farmacologia
4.
Zhongguo Zhong Yao Za Zhi ; 46(2): 388-390, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33645126

RESUMO

Two phloroglucinol compounds(1-2) were isolated and purified from 95% ethanol extract of Dryopteris fragrans through various column chromatographies on silica gel, Sephadex LH-20, medium pressure column chromatography, and preparative HPLC. Their structures were elucidated as 2',4',6'-trihydroxy-5'-methyl acetate-3'-methyl-1'-butyrophenone(1) and aspidinol B(2) based on their chemical and physicochemical methods and spectroscopic data. Compound 1 is a new phloroglucinol compound named "dryofraginol".


Assuntos
Dryopteris , Cromatografia Líquida de Alta Pressão , Etanol , Floroglucinol , Extratos Vegetais
5.
Horm Metab Res ; 52(7): 532-539, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32375182

RESUMO

Although glucagon-like peptide-1 (GLP-1) analogue has been reported to suppress oxidative stress in non-alcoholic fatty liver disease (NAFLD), an effective therapeutic agent for NAFLD is currently unavailable. Therefore, in this study, we aimed to investigate the protective effects of the GLP-1 analogue liraglutide against lipotoxicity-induced oxidative stress in HepG2 cells and to elucidate the underlying mechanisms. HepG2 cells were cultured for 48 hours and treated with a free fatty acid (FFA) mixture: FFA mixture and liraglutide or FFA mixture, liraglutide, and exendin (9-39). Lipid accumulation was examined by oil red O staining. Oxidative stress was assessed by measuring the levels of intracellular reactive oxygen species using 2',7'-dichlorofluorescein diacetate and thiobarbituric acid-reactive substances, whereas antioxidant capacity was assessed by measuring the activity of superoxide dismutase and catalase. Expression of the nuclear factor erythroid-2-related factor 2 (NRF2) gene and the genes encoding antioxidant enzymes was analyzed using quantitative RT-PCR. Cellular and nuclear NRF2 expression levels were assessed using immunofluorescence cell staining and western blotting. Liraglutide treatment reduced high fat-induced lipid formation and the levels of oxidative stress markers and increased antioxidant enzyme activity in HepG2 cells. Liraglutide treatment increased the mRNA expression of NRF2 target genes, induced NRF2 nuclear translocation, and increased nuclear NRF2 levels without altering NRF2 mRNA expression. Collectively, these results indicate that liraglutide exhibits a protective effect against lipotoxicity-induced oxidative stress, possibly via modulation of NRF2 and expression of antioxidant enzymes in liver cells.


Assuntos
Ácidos Graxos não Esterificados/toxicidade , Liraglutida/farmacologia , Fígado/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Citoproteção/efeitos dos fármacos , Células Hep G2 , Humanos , Gotículas Lipídicas/efeitos dos fármacos , Gotículas Lipídicas/metabolismo , Fígado/metabolismo , Fator 2 Relacionado a NF-E2/fisiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
6.
Pediatr Blood Cancer ; 66(3): e27545, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30408307

RESUMO

BACKGROUND: Targeted cancer treatments are almost always first studied in adults, even when there is a biologically plausible potential for efficacy in children. Through compassionate use programs, children who are not eligible for a clinical trial and for whom there are no known effective therapies may obtain access to investigational agents, including drugs under development for adults. However, little is known about pediatric oncologists' experiences with applying for and obtaining compassionate use agents. METHODS: This study surveyed 132 pediatric oncologists to assess awareness and utilization of compassionate use programs, to identify barriers to their use, and to evaluate available institutional support and resources. RESULTS: We found that the process of applying for access to drugs in development is poorly understood, which presents a barrier to obtaining investigational drugs. Fifty-seven percent of the pediatric oncologists applied for compassionate use. Providers from larger institutions or with more than 15 years of clinical experience were more likely to complete an application and obtain investigational agents for their patients. CONCLUSION: Identified perceived and actual barriers to compassionate use application submission suggest pediatric oncologists may benefit from educational resources and support to ensure children with cancer equal access to investigational agents and care.


Assuntos
Atitude do Pessoal de Saúde , Competência Clínica , Drogas em Investigação/uso terapêutico , Conhecimentos, Atitudes e Prática em Saúde , Neoplasias/tratamento farmacológico , Oncologistas/ética , Padrões de Prática Médica/ética , Criança , Humanos , Neoplasias/psicologia , Oncologistas/psicologia , Inquéritos e Questionários
7.
J Surg Oncol ; 117(3): 417-424, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29044582

RESUMO

BACKGROUND: Curative therapy for ES requires both chemotherapy and local control of primary tumor. There is no universally accepted standard approach to local control modalities. This survey was conducted to determine practice patterns and factors influencing the choice to offer various local control modalities to patients with ES of the spine and pelvis. METHODS: The survey consisted of four scenarios involving a 15-year-old girl who presented with Ewing sarcoma of thoracic vertebra, sacrum, iliac wing, and acetabulum with or without neurologic compromise. The questionnaire was sent to oncologists, orthopedic surgeons, and radiation oncologists, asking their recommendations for local control modality. RESULTS: Among 94 respondents, radiotherapy was most frequently chosen for sacral tumors (68.1%) and T10 vertebral tumors (46.2%) whereas surgery was preferred for iliac wing pelvic tumors (45.7%) and acetabular tumors (43.6%). Orthopedic surgeons were significantly more likely to offer surgery than radiation oncologists (OR 3.07, 95%CI 1.37-6.88, P = 0.007). Providers outside North America were more likely to offer combined surgery plus radiotherapy (OR 10.58, 95%CI 5.41-20.70, P < 0.001). CONCLUSION: Considerable heterogeneity exists in local control modalities for Ewing sarcoma of the spine and pelvis. Specialty and location of practice may influence treatment recommendations.


Assuntos
Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/cirurgia , Padrões de Prática Médica , Sarcoma de Ewing/radioterapia , Sarcoma de Ewing/cirurgia , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/cirurgia , Adolescente , Neoplasias Ósseas/patologia , Estudos Transversais , Feminino , Humanos , Oncologistas , Cirurgiões Ortopédicos , Ossos Pélvicos/patologia , Radioterapia (Especialidade) , Sarcoma de Ewing/patologia , Neoplasias da Coluna Vertebral/patologia , Inquéritos e Questionários , Vértebras Torácicas/patologia
8.
Acta Pharmacol Sin ; 39(3): 459-471, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29188802

RESUMO

The G protein-coupled receptor 55 (GPR55) is expressed in multiple tissues, and has been implicated in cancer pathogenesis, but little is known about its role in the migratory behavior of cancer cells, particularly breast cancer cells. In this study we first showed that GPR55 expression levels in 38 metastatic lymph nodes of breast cancer patients were profoundly elevated, and were positively associated in human breast cancer cells with their migratory ability. Moreover, the plasma levels of GPR55 endogenous agonist L-a-lysophosphatidylinositol (LPI) were significantly increased in breast cancer patients compared with healthy individuals. In human breast cancer LM-MCF-7 and MDA-MB-231 cells, treatment with LPI (2.5 µmol/L) significantly increased filopodia formation and resulted in cell migration, which could be blocked either by the GPR55 antagonist CID16020046 or by siRNA-mediated GPR55 knockdown. Furthermore, dual-luciferase report gene assays showed that GPR55 upregulated HBXIP at the promoter; GPR55 expression levels were positively correlated with HBXIP expression levels in breast cancer tissues and 8 breast cancer cell lines. We also showed that the LPI/GPR55 axis promoted the migration of breast cancer cells via two mutually exclusive pathways - the HBXIP/p-ERK1/2/Capn4 and MLCK/MLC signaling pathways. In xenograft nude mouse model, loss of GPR55 mainly affected breast cancer cell metastasis and the formation of metastatic foci. Thus, GPR55 is involved in the migratory behavior of human breast cancer cells and could serve as a pharmacological target for preventing metastasis.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Movimento Celular/fisiologia , Lisofosfolipídeos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Animais , Compostos Azabicíclicos/farmacologia , Benzoatos/farmacologia , Linhagem Celular Tumoral , Feminino , Humanos , Lisofosfolipídeos/sangue , Camundongos , RNA Interferente Pequeno/farmacologia , Receptores de Canabinoides , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/biossíntese , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Pediatr Hematol Oncol ; 40(6): e359-e363, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29683959

RESUMO

OBJECTIVE: The main objective of this study was to determine if family history of malignant peripheral nerve sheath tumor (MPNST) increases risk of developing an MPNST in patients with neurofibromatosis-1 (NF-1). MATERIALS AND METHODS: Individuals with NF-1 registered with the Children's Tumor Foundation's Neurofibromatosis Registry were emailed an anonymous 15-minute survey with regard to personal and family history of NF-1, MPNST, ages of onset, and symptomatology. Participation was voluntary and information was self-reported. RESULTS: The survey was sent to 4801 registrants, 878 responded. Presence of a family history of MPNST was found to be a risk factor for the development of MPNST; 19.4% of respondents confirming a family history of MPNST developed MPNST compared with 7.5% of respondents with no family history (odds ratio, 2.975; 95% confidence interval, 1.232-7.187; P=0.021). NF-1 patients with a positive family history developed MPNST at a younger age than those with no family history (8.3% vs. 0.5% P=0.003 and 13.9% vs. 2.4% P=0.003, for onset before 10 and 20, respectively). In the MPNST population with a known family history, onset prior to age 10 was significantly more prevalent (42.9% vs. 7% P=0.029). CONCLUSIONS: These results suggest a positive family history of MPNST represents a risk factor for the development and early onset of MPNST in individuals with NF-1.


Assuntos
Família , Neurofibromatose 1 , Neurofibrossarcoma , Sistema de Registros , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Anamnese , Pessoa de Meia-Idade , Neurofibromatose 1/epidemiologia , Neurofibromatose 1/genética , Neurofibromatose 1/patologia , Neurofibrossarcoma/epidemiologia , Neurofibrossarcoma/genética , Neurofibrossarcoma/patologia , Fatores de Risco
10.
Phys Chem Chem Phys ; 19(8): 6057-6063, 2017 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-28191572

RESUMO

Organic-inorganic halide perovskites have emerged as attractive materials for use in photovoltaic cells. Owing to the existence of dangling bonds at the grain boundaries between perovskite crystals, minimizing the charge recombination at the surface or grain boundaries by passivating these trap states has been identified to be one of the most important strategies for further optimization of device performance. Previous reports have mainly focused on surface passivation by inserting special materials such as graphene or fullerene between the electron transfer layer and the perovskite film. Here, we report an enhanced efficiency of mesoscopic perovskite solar cells by using graphene quantum dots (GQDs) to passivate the grain boundaries of CH3NH3PbI3. The highest efficiency (17.62%) is achieved via decoration with 7% GQDs, which is an 8.2% enhancement with respect to a pure perovskite based device. Various analyses including electrochemical impedance spectroscopy, time-resolved photoluminescence decay and open-circuit voltage decay measurements are employed in investigating the mechanism behind the improvement in device performance. The findings reveal two important roles played by GQDs in promoting the performance of perovskite solar cells - that GQDs are conducive to facilitating electron extraction and can effectively passivate the electron traps at the perovskite grain boundaries.

11.
Endocr J ; 64(7): 663-673, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-28539530

RESUMO

The purpose of this study was to determine whether treatment using the active form of vitamin D (1,25(OH)2D3) could protect against high-fat diet (HFD)-induced non-alcoholic fatty liver disease (NAFLD) in rats and ameliorate oxidative stress. Male Sprague-Dawley rats were divided into three groups and treated with standard chow, HFD, or HFD plus intraperitoneal injection of 1,25(OH)2D3 (5 µg/kg body weight, twice per week), respectively, for 16 weeks. Serum lipid profiles, hepatic function, intrahepatic lipid, and calcium levels were determined. Hepatic histology was examined using hematoxylin/eosin, Masson's trichrome, and Oil Red O staining. Oxidative stress was assessed by measuring hepatic malondialdehyde (MDA) and F2α-isoprostane content. Expression of nuclear factor-erythroid-2-related factor 2 (Nrf2) and downstream target genes was analyzed using quantitative RT-PCR. 1,25(OH)2D3 treatment improved the serum lipid profile, reduced intrahepatic lipid levels, and attenuated hepatic steatosis and inflammation in HFD rats. Furthermore, MDA and F2α-isoprostane levels in liver tissue were reduced by 1,25(OH)2D3 administration. Although 1,25(OH)2D3 did not regulate the expression of Nrf2 mRNA, it did induce Nrf2 nuclear translocation. The expression of Nrf2 target genes, including Gclc, Nqo1, Sod2, and Cat, was up-regulated by 1,25(OH)2D3. We conclude that 1,25(OH)2D3 protects against HFD-induced NAFLD by attenuating oxidative stress, inducing NRF2 nuclear translocation, and up-regulating the expression of genes encoding antioxidant enzymes.


Assuntos
Calcitriol , Regulação da Expressão Gênica , Lipotrópicos , Fígado , Hepatopatia Gordurosa não Alcoólica , Estresse Oxidativo , Oxirredutases , Animais , Masculino , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Biomarcadores/sangue , Biomarcadores/metabolismo , Calcitriol/administração & dosagem , Calcitriol/uso terapêutico , Dieta Hiperlipídica/efeitos adversos , Indução Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Mediadores da Inflamação/sangue , Mediadores da Inflamação/metabolismo , Injeções Intraperitoneais , Metabolismo dos Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Lipotrópicos/administração & dosagem , Lipotrópicos/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/metabolismo , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/imunologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Oxirredutases/química , Oxirredutases/genética , Oxirredutases/metabolismo , Distribuição Aleatória , Ratos Sprague-Dawley , Fator 2 Relacionado a NF-E2/agonistas , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo
12.
Angew Chem Int Ed Engl ; 56(27): 7740-7744, 2017 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-28471069

RESUMO

Criegee intermediates have implications as key intermediates in atmospheric, organic, and enzymatic reactions. However, their chemistry in aqueous environments is relatively unexplored. Herein, Born-Oppenheimer molecular dynamics (BOMD) simulations examine the dynamic behavior of syn- and anti-CH3 CHOO at the air-water interface. They show that unlike the simplest Criegee intermediate (CH2 OO), both syn- and anti-CH3 CHOO remain inert towards reaction with water. The unexpected high stability of C2 Criegee intermediates is due to the presence of a hydrophobic methyl substituent on the Criegee carbon that lowers the proton transfer ability and inhibits the formation of a pre-reaction complex for the Criegee-water reaction. The simulation of the larger Criegee intermediates, (CH3 )2 COO, syn- and anti-CH2 C(CH3 )C(H)OO on the water droplet surface suggests that strongly hydrophobic substituents determine the reactivity of Criegee intermediates at the air-water interface.

13.
Proteomics ; 16(10): 1515-36, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26968330

RESUMO

Two Chinese bread wheat cultivars, Jinghua 9 and Zhongmai 175, distinct in grain weight and dough quality, were used to study proteome changes in the embryo and endosperm during grain development using a two-dimensional difference gel electrophoresis (2D-DIGE)-based proteomics approach. In total, 138 and 127 differentially expressed protein (DEP) spots representing 116 and 113 unique DEPs were identified in the embryo and endosperm, respectively. Among them, 54 (31%) DEPs were commonly present in both organs while 62 (35%) and 59 (34%) DEPs occurred only in the embryo and endosperm, respectively. Embryonic DEPs are primarily stress-related proteins and involved in carbohydrate and lipid metabolism, while those from the endosperm are related primarily to carbohydrate metabolism and storage. Principal component analysis (PCA) indicated that the proteome differences in the endosperm caused by different cultivars were greater than those by development stages, while the differences in the embryo showed the opposite pattern. Protein-protein interaction (PPI) analysis revealed a complex network centered primarily on enzymes involved in carbohydrate and protein metabolism. The transcriptional levels of fourteen important DEPs encoding genes showed high similarity between organs and cultivars. In particular, some key DEPs of the endosperm, such as phosphoglucomutase, ADP-glucose pyrophosphorylase (AGPase), and sucrose synthase (SUS), showed significantly upregulated expression, indicating their key roles in starch biosynthesis and grain yield. Moreover, upregulated expression of some storage proteins in the endosperm could improve wheat bread-making quality.


Assuntos
Endosperma/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Triticum/metabolismo , Endosperma/genética , Endosperma/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/isolamento & purificação , Mapas de Interação de Proteínas , Proteoma/genética , Proteoma/isolamento & purificação , Espectrometria de Massas em Tandem , Transcrição Gênica , Triticum/genética , Triticum/crescimento & desenvolvimento , Eletroforese em Gel Diferencial Bidimensional
14.
Analyst ; 141(3): 1052-9, 2016 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-26730814

RESUMO

The graphene quantum dot based fluorescent probe community needs unambiguous evidence about the control on the ion selectivity. In this paper, polyethylene glycol modified N-doped graphene quantum dots (PN-GQDs) were synthesized by alkylation reaction between graphene quantum dots and organic halides. We demonstrate the tunable selectivity and sensitivity by controlling the supramolecular recognition through the length and the end group size of the polyether chain on PN-GQDs. The relationship formulae between the selectivity/detection limit and polyether chains are experimentally deduced. The polyether chain length determines the interaction between the PN-GQDs and ions with different ratios of charge to radius, which in turn leads to a good selectivity control. Meanwhile the detection limit shows an exponential growth with the size of end groups of the polyether chain. The PN-GQDs can be used as ultrasensitive and selective fluorescent probes for Li(+), Na(+), K(+), Mg(2+), Ca(2+) and Sr(2+), respectively.


Assuntos
Grafite/química , Metais Alcalinos/química , Nitrogênio/química , Polietilenoglicóis/química , Pontos Quânticos/química , Alquilação , Fenômenos Ópticos
15.
J Asian Nat Prod Res ; 18(1): 59-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26700189

RESUMO

Phytochemical investigation on the aqueous extract from Dryopteris fragrans led to the isolation of one new chromone glycoside, frachromone C (1), and one new coumarin glycoside, dryofracoulin A (2), together with one known undulatoside A (3). Their structures were elucidated by a combination of 1D and 2D NMR, HRMS, and chemical analysis. Compounds 1-3 exhibited inhibition on nitric oxide production in lipopolysaccharide induced RAW 264.7 macrophages with their IC50 values of 45.8, 65.8, and 49.8 µM, respectively.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Cumarínicos/isolamento & purificação , Cumarínicos/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Dryopteris/química , Glicosídeos/isolamento & purificação , Glicosídeos/farmacologia , Animais , Anti-Inflamatórios/química , Cromonas , Cumarínicos/química , Medicamentos de Ervas Chinesas/química , Glicosídeos/química , Lipopolissacarídeos/farmacologia , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Óxido Nítrico/biossíntese , Ressonância Magnética Nuclear Biomolecular , Extratos Vegetais/química
16.
BMC Plant Biol ; 15: 97, 2015 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-25888100

RESUMO

BACKGROUND: Wheat seeds provide a staple food and an important protein source for the world's population. Seed germination is vital to wheat growth and development and directly affects grain yield and quality. In this study, we performed the first comparative proteomic analysis of wheat embryo and endosperm during seed germination. RESULTS: The proteomic changes in embryo and endosperm during the four different seed germination stages of elite Chinese bread wheat cultivar Zhengmai 9023 were first investigated. In total, 74 and 34 differentially expressed protein (DEP) spots representing 63 and 26 unique proteins were identified in embryo and endosperm, respectively. Eight common DEP were present in both tissues, and 55 and 18 DEP were specific to embryo and endosperm, respectively. These identified DEP spots could be sorted into 13 functional groups, in which the main group was involved in different metabolism pathways, particularly in the reserves necessary for mobilization in preparation for seed germination. The DEPs from the embryo were mainly related to carbohydrate metabolism, proteometabolism, amino acid metabolism, nucleic acid metabolism, and stress-related proteins, whereas those from the endosperm were mainly involved in protein storage, carbohydrate metabolism, inhibitors, stress response, and protein synthesis. During seed germination, both embryo and endosperm had a basic pattern of oxygen consumption, so the proteins related to respiration and energy metabolism were up-regulated or down-regulated along with respiration of wheat seeds. When germination was complete, most storage proteins from the endosperm began to be mobilized, but only a small amount was degraded during germination. Transcription expression of six representative DEP genes at the mRNA level was consistent with their protein expression changes. CONCLUSION: Wheat seed germination is a complex process with imbibition, stirring, and germination stages, which involve a series of physiological, morphological, and proteomic changes. The first process is a rapid water uptake, in which the seed coat becomes softer and the physical state of storage materials change gradually. Then the germinated seed enters the second process (a plateau phase) and the third process (the embryonic axes elongation). Seed embryo and endosperm display distinct differentially expressed proteins, and their synergistic expression mechanisms provide a basis for the normal germination of wheat seeds.


Assuntos
Regulação da Expressão Gênica de Plantas , Germinação , Proteínas de Plantas/genética , Proteoma/genética , Triticum/genética , Endosperma/genética , Endosperma/crescimento & desenvolvimento , Endosperma/metabolismo , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Sementes/genética , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
17.
Histopathology ; 67(3): 404-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25619876

RESUMO

AIMS: Pseudoepitheliomatous hyperplasia (PEH) is defined as a pattern of epidermal reaction. However, it has not yet been extensively documented in extranodal natural killer/T-cell lymphoma (ENKTL). The aim of our study was to analyse a series of ENKTLs concomitant with PEH mimicking squamous cell carcinoma (SCC). METHODS AND RESULTS: We analysed 34 cases of ENKTL with PEH. In our study, the incidence of PEH was 3.8% in ENKTLs diagnosed over a 13-year period. All 34 cases presented with PEH, appearing as tongue-like projections of squamous epithelium into the underlying submucosa/dermis with variable depths and jagged borders. The keratinocytes sometimes showed a minor degree of cytological atypia, mostly in the stratum basale, and keratinocyte necrosis was absent. Atypical mitoses and a high nuclear/cytoplasmic ratio were absent. The submucosa and the squamous cell cords were also permeated by atypical lymphocytes. CONCLUSIONS: ENKTL can be associated with PEH, and the atypical lymphoid cell population can be highly subtle, and therefore may be easily mistaken for SCC, leading to inappropriate therapy. A correct diagnosis requires awareness and recognition of this pitfall by recognizing the associated conditions listed above, which distinguish PEH from SCC.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Linfoma Extranodal de Células T-NK/diagnóstico , Neoplasias Cutâneas/diagnóstico , Adulto , Idoso , Carcinoma de Células Escamosas/patologia , Diagnóstico Diferencial , Feminino , Humanos , Hiperplasia/patologia , Linfoma Extranodal de Células T-NK/patologia , Masculino , Pessoa de Meia-Idade , Pele/patologia , Neoplasias Cutâneas/patologia , Adulto Jovem
18.
Tumour Biol ; 36(7): 5201-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25663493

RESUMO

Tyrosine-protein phosphatase nonreceptor type 12 (PTPN12) has been proposed to predict prognosis of various human cancers. However, the clinicopathologic and prognostic significance of PTPN12 expression in NPC has not yet been elucidated. The objective of this study was to investigate the clinicopathological and prognostic implication of PTPN12 in nasopharyngeal carcinoma (NPC) patients. Protein expression levels of PTPN12 were explored by semiquantitative immunohistochemical staining on archival formalin-fixed, paraffin-embedded pathological specimens consisting of 203 NPCs, and 40 normal nasopharyngeal mucosa tissues. Receiver operating characteristic (ROC) curve analysis was employed to determine the cutoff score of PTPN12 expression in NPCs. The PTPN12 immunohistochemical staining results were then correlated with various clinicopathological features and patients' prognosis using various statistical models. Our results showed that decreased expression of PTPN12 was more frequently observed in NPC tissues compared with the normal nasopharyngeal mucosa. Further correlation analyses indicated that the decreased expression of PTPN12 was significantly associated with tumor T classification, N classification, distant metastasis, and clinical stage in NPCs (P < 0.05). Univariate analysis showed a significant association between the decreased expression of PTPN12 and adverse overall survival and disease-free survival (P < 0.05). More importantly, multivariate analysis identified the PTPN12 expression in NPC as an independent prognostic factor. The decrease expression of PTPN12 might be important in conferring a more aggressive behavior in NPC. Thus, PTPN12 expression may be used as a novel independent prognostic biomarker for patients with NPC.


Assuntos
Biomarcadores Tumorais/biossíntese , Neoplasias Nasofaríngeas/genética , Prognóstico , Proteína Tirosina Fosfatase não Receptora Tipo 12/biossíntese , Adulto , Idoso , Biomarcadores Tumorais/genética , Carcinoma , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , Proteína Tirosina Fosfatase não Receptora Tipo 12/genética
19.
BMC Cancer ; 15: 370, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25947284

RESUMO

BACKGROUND: The focus of this study was to assess the impact of lymphovascular invasion (LVI) on both the recurrence of cancer and the long-term survival of Chinese patients with resectable gastric cancer (GC). METHODS: A retrospective analysis of the clinicopathological data for 1148 GC patients who had undergone gastrectomy with regional lymphadenectomy was performed. The primary objective was to assess the correlation between LVI and post-surgery outcomes for each patient. This was done by routine H & E staining for LVI on patients' disease-free survival (DFS) and disease-specific survival (DSS). RESULTS: LVI was detected in 404 (35.2%) of the 1148 GC patients. The presence of LVI was significantly correlated with the level of CA19-9, the tumor size, the Lauren classification, tumor differentiation, gastric wall invasive depth, lymph node involvement, distant metastasis and an advanced TNM stage. There was a lower DFS and DSS in the patients with LVI as compared to the patients without LVI. A multivariate analysis also identified LVI as an independent prognostic factor of both DSS and DFS. CONCLUSIONS: The presence of LVI is a risk factor for the recurrence of cancer and an independent indicator of a poor outcome in GC patients following surgery. The LVI status should be taken into consideration when determining the best approach for the treatment of the individual.


Assuntos
Recidiva Local de Neoplasia/patologia , Neoplasias Gástricas/patologia , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Adulto Jovem
20.
Org Lett ; 26(13): 2606-2611, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38513116

RESUMO

Enesulfinamides with α,ß,ß-trisubstitution undergo a Simmons-Smith reaction to yield multisubstituted cyclopropylamine derivatives with high stereocontrol. The resulting α-tertiary cyclopropylamine derivatives, which feature ß-quaternary stereocenters bearing two electronically and sterically similar substituents (e.g., methyl and ethyl), are seldom achieved by using conventional methods. By adjusting the stereochemistry of the carbon-carbon double bond and/or sulfinyl group within the enesulfinamides, it is feasible to selectively produce four stereoisomers of the cyclopropylamines, each with different absolute configurations at the α- and ß-carbons.

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