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1.
Nanoscale ; 15(7): 3375-3386, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36722930

RESUMO

In this study, we demonstrate inverted PTB7:PC71BM polymer solar cells (PSCs) featuring a solution-processed s-MoO3 hole transport layer (HTL) that can, after thermal aging at 85 °C, retain their initial power conversion efficiency (PCE) for at least 2200 h. The T80 lifetimes of the PSCs incorporating the novel s-MoO3 HTL were up to ten times greater than those currently reported for PTB7- or low-band-gap polymer:PCBM PSCs, the result of the inhibition of burn-in losses and long-term degradation under various heat-equivalent testing conditions. We used X-ray photoelectron spectroscopy (XPS) to study devices containing thermally deposited t-MoO3 and s-MoO3 HTLs and obtain a mechanistic understanding of how the robust HTL is formed and how it prevented the PSCs from undergoing thermal degradation. Heat tests revealed that the mechanisms of thermal inter-diffusion and interaction of various elements within active layer/HTL/Ag electrodes controlled by the s-MoO3 HTL were dramatically different from those controlled by the t-MoO3 HTL. The new prevention mechanism revealed here can provide the conceptual strategy for designing the buffer layer in the future. The PCEs of PSCs featuring s-MoO3 HTLs, measured in damp-heat (65 °C/65% RH; 85 °C per air) and light soaking tests, confirmed their excellent stability. Such solution-processed MoO3 HTLs appear to have great potential as replacements for commonly used t-MoO3 HTLs.

2.
J Fungi (Basel) ; 9(1)2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36675883

RESUMO

Fusarium head blight (FHB), which is primarily caused by Fusarium graminearum, is a widespread and devastating disease of wheat. In the absence of resistant varieties, the control of FHB relies heavily on the application of fungicides, and the new generation SDHI fungicide, pydiflumetofen, has recently been registered in China for the control of FHB in wheat. The current study explored three genetically stable, highly resistant laboratory mutants (S2-4-2R, S27-3R, and S28-2R, with EC50 values of 25.10, 28.57, and 19.22 µg/mL, respectively) to investigate the potential risks associated with pydiflumetofen resistance. Although the mycelial growth of the mutants differed little compared to their parental isolates, the study found that the resistant mutants exhibited significantly reduced (p < 0.05) levels of sporulation and pathogenicity, which suggests a significant fitness cost associated with pydiflumetofen resistance in F. graminearum. Sequence analysis of the Sdh target protein identified numerous amino acid substitutions in the predicted sequences of the four subunits: FgSdhA, FgSdhB, FgSdhC, and FgSdhD. Indeed, the mutants were found to have a series of substitution in multiple subunits such that all three exhibited five identical changes, including Y182F in the FgSdhA subunit; H53Q, C90S, and A94V in FgSdhB; and S31F in FgSdhC. In addition, gene expression analysis revealed that all of the FgSdh genes had significantly altered expression (p < 0.05), particularly FgSdhA and FgdhC, which exhibited remarkably low levels of expression. However, the study found no evidence of cross-resistance between pydiflumetofen and tebuconazole, fludioxonil, prochloraz, fluazinam, carbendazim, pyraclostrobin, or difenoconazole, which indicates that these fungicides, either in rotation or combination with pydiflumetofen, could mitigate the risk of resistance emerging and provide ongoing control of FHB to ensure high and stable wheat yields.

3.
Aging (Albany NY) ; 13(15): 19776-19788, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34370713

RESUMO

Esophageal cancer is a malignant tumor with a five-year survival rate of less than 20%. Early diagnosis and exploration of esophageal cancer pathogenesis are of great significance for the treatment and prognosis of esophageal cancer. Long non-coding RNA (lncRNA) plays a vital role in the occurrence and development of different types of tumors. However, the role of exosome LncRNA in esophageal squamous cell carcinoma (ESCC) is rarely reported. In this study, we detected high expression of lncRNA LINC01711 in ESCC tissues and was associated with poor prognosis. Silencing LINC01711 can inhibit the proliferation, migration, invasion, and growth of ESCC cell lines, and induce apoptosis. Linc01711 was identified as a competitive endogenous RNA that suppressed miR-326, and up-regulated the expression of fascin actin-bundling protein 1 (FSCN1). Besides, in vivo experiments showed that the administration of exosome-derived LINC01711 (LINC01711-Exo) promoted the growth of tumors in nude mice. In general, exosomal LINC01711 promoted the proliferation, migration, and invasion of esophageal cancer cells by up-regulating FSCN1 and down-regulating miR-326, thus improved the occurrence and development of ESCC.


Assuntos
Proteínas de Transporte/metabolismo , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , MicroRNAs/metabolismo , Proteínas dos Microfilamentos/metabolismo , RNA Longo não Codificante/metabolismo , Animais , Apoptose/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica , Prognóstico , RNA Longo não Codificante/genética , Transfecção
4.
Bioorg Med Chem Lett ; 22(6): 2350-3, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22365754

RESUMO

Four new compounds, oliganthins A-D (1-4), and one known caged xanthone gaudichaudione H (5) were isolated from the stems of Garcinia oligantha. The structures of the new compounds were elucidated by spectroscopic evidences. All of the five compounds were evaluated for their apoptosis-inducing effects using HeLa-C3 cells which have been genetically engineered to produce a fluorescent biosensor capable of detecting caspase-3 activation. All of them induced cell apoptosis at 10 µM or lower concentrations. The apoptotic activity of oliganthins A, B and gaudichaudione H were further confirmed by detecting the cleavage of PARP, which is the substrate of activated caspase-3, in these compounds-treated cells using the method of Western blot. Moreover, the values of IC(50) were measured for all five compounds on HeLa cells using the MTT assay. Among them, gaudichaudione H had the lowest IC(50) value of 0.90 µM, while the other four new compounds had IC(50) values of 1.58, 1.52, 4.15, and 7.82 µM, respectively. These results show that gaudichaudione H has the strongest apoptosis-inducing effect and cell growth inhibition effect among these xanthones and it may have the potential to be developed into a new anticancer agent.


Assuntos
Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Garcinia/química , Xantenos/química , Xantonas/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Western Blotting , Caspase 3/genética , Caspase 3/metabolismo , Feminino , Expressão Gênica , Genes Reporter , Células HeLa , Humanos , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Caules de Planta/química , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia , Xantenos/isolamento & purificação , Xantenos/farmacologia , Xantonas/isolamento & purificação , Xantonas/farmacologia
5.
Genes Chromosomes Cancer ; 47(8): 665-79, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18470900

RESUMO

Human embryonic stem cells (hESCs) during long-term culture acquire chromosomal changes similar to those occurring in tumorigenesis. This was raised concerns about the progression from hESCs to malignant cells. This study aimed to investigate the changes in chromosomes, cell phenotype, and genes in culture-adapted hESCs to ascertain whether tumorigenic transformation occurred. By cytogenetic analysis we found progressive karyotypic changes from simple to complex in chHES-3, one of the hESC lines established in our laboratory, during a long-term suboptimal culture. We further compared chHES-3 cells at different karyotypic stages in cell surface markers, in vivo differentiation, cell cycle, apoptosis, and gene expression profiles. We found that the karyotypically aberrant chHES-3 had higher S-phase fraction in cell cycle distributions and antiapoptosis ability. In vivo differentiation of karyotypically normal chHES-3 resulted in relatively mature teratoma, whereas karyotypically aberrant chHES-3 formed immature teratoma (grade III), in which more primary neural epithelium was revealed by pathological analysis. The microarray analysis and real-time PCR results showed that some oncogenes were upregulated in karyotypically aberrant chHES-3 cells, whereas the genes related to differentiation were downregulated, and that Wnt signal pathway was activated. In conclusion, chHES-3 cells underwent deregulation of self-renewal and dysfunction of related genes in long-term culture adaptation, leading to malignant transformation.


Assuntos
Transformação Celular Neoplásica , Células-Tronco Embrionárias/patologia , Técnicas de Cultura de Células , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Células Cultivadas , Análise Citogenética , Perfilação da Expressão Gênica , Humanos , Processos Neoplásicos , Fase S/genética
6.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 32(6): 992-6, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18182715

RESUMO

OBJECTIVE: To observe the inductive efficiency of deriving hematopoietic cells from human embryonic stem (hES) cells co-cultured with human yolk sac stromal cells, fetal liver stromal cells or fetal bone marrow stromal cells,in order to discuss the effect of the different hemopoietic microenvironment on hemopoietic cytogenesis. METHODS: We used two-step method to induce the hES cells into the hematopoietic cells. In the first step the hES cells were co-cultured with cytokines by formation of the day 5 embryoid bodies (5d EBs). In the second step the 5d EB cells were induced into the hematopoietic cells by co-culturing with human yolk sac stromal cells, fetal liver stromal cells or fetal bone marrow stromal cells for 10 days. The inductive efficiencies of deriving hematopoietic cells from hES cells co-cultured with the different hemopoietic microenvironment were reflected by the expression levels of flk, CD34 and CD45 antigen. RESULTS: Flow cytometry analysis demonstrated that the population of the cells co-cultured with human yolk sac stromal cells contained flk (1.80%+/-0.56%), CD34 (1.30%+/-0.14%) or CD45 (1.05%+/-0.63%) positive cells; the population of the cells co-cultured with human fetal liver stromal cells contained flk (34.00%+/-25.45%), CD34 (38.40%+/-24.80%) or CD45 (72.60%+/-25.70%) positive cells; the population of the cells co-cultured with human fetal bone marrow stromal cells contained flk (2.50%+/-1.48%), CD34 (3.20%+/-0.56%) or CD45 (1.65%+/-0.21%) positive cells. Compared with spontaneous differentiation of EBs, all of the three stromal cells could induce EBs into the hematopoietic cells (P<0.05). CONCLUSION: The inductive efficiency of deriving hematopoietic cells from EBs co-cultured with human fetal liver stromal cells was higher than EBs co-cultured with human yolk sac stromal cells and fetal bone marrow stromal cells.


Assuntos
Microambiente Celular , Células-Tronco Embrionárias/citologia , Células-Tronco Hematopoéticas/citologia , Antígenos CD34 , Diferenciação Celular , Células Cultivadas , Técnicas de Cocultura , Feto/citologia , Humanos , Antígenos Comuns de Leucócito , Células-Tronco Mesenquimais/citologia , Células Estromais/citologia , Saco Vitelino/citologia
7.
Cell Biol Int ; 29(8): 623-8, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15951207

RESUMO

Long-term proliferation of human embryonic stem (hES) cells is currently achieved by co-culturing with mitotically inactive primary mouse embryonic fibroblasts (mEFs), which serve as feeder cells. This study explores the possibility that proliferative mEFs can be used as feeder cells to maintain the prolonged expansion of hES cells. All undifferentiated hES cell clumps were re-plated on six different densities of proliferative mEFs. hES colonies cultured on 1 x 10(5) - 5 x 10(5) proliferative mEFs amplified over 130 days of continuous culture and remained undifferentiated, as did those cultured on mitotically inactive mEFs. This suggests that certain densities of proliferative mEFs can maintain the propagation of hES cells, which may be helpful for identifying the cytokines and adhesion molecules that are required for their self-renewal.


Assuntos
Técnicas de Cultura de Células , Embrião de Mamíferos/citologia , Células-Tronco/citologia , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Técnicas de Cocultura , Feminino , Humanos , Camundongos , Gravidez , Prenhez
8.
Zhongguo Zhong Yao Za Zhi ; 28(8): 718-20, 771, 2003 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-15015349

RESUMO

OBJECTIVE: To study the yield of different Houttuynia cordata and the changing regularity of their main officinal components in different periods, and provide a basis for harvesting in good time and breeding new varieties. METHOD: The main officinal composition and wet weight of overground parts per acreage of different accessions were determined periodically. The plot yields were tested when harvested and analyzed by analysis of variance. RESULT: The difference of the yields of different accessions was significant. The varying tendency of the content of main officinal component methyl nonyl ketone and its total content per acreage of different accessions were different. CONCLUSION: The integrate characters of Qionglai and Wangyu wild accessions are relatively better, worthy to be widely applied in production.


Assuntos
Medicamentos de Ervas Chinesas/análise , Plantas Medicinais , Saururaceae , China , Ecossistema , Houttuynia , Componentes Aéreos da Planta/química , Plantas Medicinais/anatomia & histologia , Plantas Medicinais/química , Plantas Medicinais/crescimento & desenvolvimento , Saururaceae/anatomia & histologia , Saururaceae/química , Saururaceae/crescimento & desenvolvimento , Estações do Ano , Especificidade da Espécie
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