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1.
Carbohydr Polym ; 329: 121778, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38286549

RESUMEN

Designing of a green and multifunctionally integrated cellulose-based flexible wearable material with personal thermoregulation, water and ultraviolet (UV) resistance is essential for the development of personal thermal management and smart textiles. Herein, a hydrophobic silver nanoparticles cellulose-based membrane (H-AgNPs/CEPCM) was prepared through simple solution blending, spin-coating process and chemical vapor modification. The prepared membrane exhibited excellent UV resistance due to the synergistic effect of carbon quantum dots (CQDs) as well as UV-absorbing functional groups. The spin-coated AgNPs layer with high infrared reflectivity has great radiant insulation, and temperature was reduced by 3.4 °C compared with H-CEPCM in indoor environment. Furthermore, the mechanical properties of H-AgNPs/CEPCM were significantly improved by the introduction of amide and ether bonds, as well as a large number of hydrogen bonds. This led to a tensile strength of 23.21 MPa and an elongation at break of 16.57 %, while also providing water resistance. Additionally, the H-AgNPs/CEPCM exhibited outstanding thermal stability and hydrophobicity. This work may provide a feasible and promising strategy for the construction of multifunctional integrated cellulose membrane materials for radiant insulation, outdoor textiles and novel UV protection applications.

2.
Cancer Med ; 12(1): 949-960, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35608130

RESUMEN

With the widespread use of highly active antiretroviral therapy (HARRT), the survival time of AIDS patients has been greatly extended. However, the incidence of lung cancer in HIV-infected patients is increasing and has become a major problem threatening the survival of AIDS patients. The aim of this study is to use Weighted Gene Co-expression Network Analysis (WGCNA) and differential gene analysis to find possible key genes involved in HIV-infected lung cancer. In this study, using lung tissue samples from five pairs of HIV-infected lung cancer patients, second-generation sequencing was performed and transcriptomic data were obtained. A total of 132 HIV-infected lung cancer-related genes were screened out by WGCNA and differential gene expression analysis methods. Based on gene annotation analysis, these genes were mainly enriched in mitosis-related functions and pathways. In addition, in protein-protein interaction (PPI) analysis, a total of 39 hub genes were identified. Among them, five genes (ASPM, CDCA8, CENPF, CEP55, and PLK1) were present in both three hub gene lists (intersection gene, DEGs, and WCGNA module) suggesting that these five genes may become key genes involved in HIV-infected lung cancer.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Neoplasias Pulmonares , Humanos , Transcriptoma , Perfilación de la Expresión Génica , Neoplasias Pulmonares/genética , Análisis de Secuencia de ARN , Redes Reguladoras de Genes , Proteínas de Ciclo Celular/genética
3.
Int J Mol Sci ; 23(19)2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36233207

RESUMEN

Curcumin (CUR) is a kind of natural orange-yellow phenolic compound mainly extracted from the stems and roots of turmeric plants and other species in the genus Curcuma, furthermore, it is also the most important active ingredient exerting pharmacological functions in turmeric. In recent years, CUR has been frequently reported and has attracted widespread attention from scholars all over the world due to its numerous biological functions and good application prospects, such as anti-inflammatory, anticancer, antioxidant and providing lipid-lowering effects, etc. In addition, adding a certain dose of CUR to livestock and poultry feed is important for animal growth and development, which plays a key role in animal metabolism, reproduction, immunity and clinical health care. This review aims to summarize, based on the published papers and our own observations, the physical and chemical properties and the biological functions of the plant-derived bioactive ingredient CUR, especially regarding the latest research progress in regulating intestinal health as well as its current development and future application prospects in livestock and poultry as a novel feed additive, so as to provide theoretical and practical references for the further study of the application of CUR as a novel feed additive and a potential new antibiotic substitute, thereby improving the research field of plant-derived bioactive ingredients and promoting the healthy development of livestock and poultry.


Asunto(s)
Antineoplásicos , Curcumina , Animales , Antibacterianos , Antiinflamatorios/farmacología , Antineoplásicos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Curcumina/química , Curcumina/farmacología , Lípidos , Ganado , Polifenoles/farmacología , Aves de Corral
4.
Front Endocrinol (Lausanne) ; 13: 975334, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36060952

RESUMEN

Exosomes (EXs) are the major types of extracellular vesicles (EVs) of 30-100 nm diameter that can be secreted by most cells to the extracellular environment. EXs transport endogenous cargoes (proteins, lipids, RNAs, etc.) to target cells and thereby triggers the release of these bioactive components, which then play important roles in regulating numerous biological processes under both physiological and pathological conditions. Throughout the studies in recent years, growing evidences have shown that EXs-derived non-coding RNAs (EXs-ncRNAs) are emerging as key players in cell-to-cell communication between adipose tissue and other related tissues in obesity and metabolic diseases. In this review, we will summarize the recent findings about EXs-ncRNAs, especially focus on the following aspects: 1) the biogenesis of EXs and emerging roles of EXs-ncRNAs, 2) the role of EXs-ncRNAs (EXs-miRNAs, EXs-lncRNAs, EXs-circRNAs, etc.) that were secreted by adipose-related tissues in promoting the differentiation of preadipocytes into mature and fully functional adipocytes, and 3) the crosstalk between the adipose tissue derived EXs-ncRNAs and the development of insulin resistance, obesity and various cancers. This review aims to reveal the emerging roles and mechanisms of EXs-ncRNAs in the mutual regulation of adipose tissue and its related tissues in obesity and metabolic diseases, so as to provide references for elucidating the etiology of obesity and related metabolic diseases and screening novel therapeutic targets.


Asunto(s)
Exosomas , Enfermedades Metabólicas , Tejido Adiposo/metabolismo , Exosomas/genética , Exosomas/metabolismo , Humanos , Enfermedades Metabólicas/genética , Enfermedades Metabólicas/metabolismo , Obesidad/genética , Obesidad/metabolismo , ARN no Traducido/metabolismo
5.
Foods ; 11(10)2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35626944

RESUMEN

This study aimed to compare the microbial diversity in meatballs with or without blown pack spoilage (BPS) to determine the cause of BPS and to assess the synergistic effect of static magnetic field (SMF) and modified atmosphere packaging (MAP) to reduce the phenomenon of BPS. Results showed that the BPS group with a 2.26-fold larger volume and packaging containing 71.85% CO2 had Klebsiella spp. (46.05%) and Escherichia spp. (39.96%) as the dominant bacteria, which was different from the spoilage group. The results of isolation and identification of strains from the BPS group and their inoculation test confirmed that Klebsiella pneumoniae was the major strain-inducing BPS in meatballs due to its pack-swelling ability. SMF (5 mT) treatment combined with MAP (40%CO2 + 60%N2), which did not influence the sensory quality of meatballs, had a significant synergistic effect on preventing the increase in pack volume. Compared with the control group, this synergistic treatment effectively delayed bacterial growth, drop in pH, and the increase of TBARS. The findings of this study will provide further guidance for meatball manufacturers to adopt effective strategies to reduce the BPS of meatballs.

6.
Anim Biosci ; 35(5): 763-777, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34727633

RESUMEN

OBJECTIVE: Excessive lipid accumulation in adipocytes results in prevalence of obesity and metabolic syndrome. Curcumin (CUR), a naturally phenolic active ingredient, has been shown to have lipid-lowering effects. However, its underlying mechanisms have remained largely unknown. Therefore, the study aims to determine the effect of CUR on cellular lipid accumulation in porcine subcutaneous preadipocytes (PSPA) and to clarify novel mechanisms. METHODS: The PSPA were cultured and treated with or without CUR. Both cell counting Kit-8 and lactate dehydrogenase release assays were used to examine cytotoxicity. Intracellular lipid contents were measured by oil-red-o staining extraction and triglyceride quantification. Apoptosis was determined by flow cytometry and the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-nick end labelling assay. Adipogenic and apoptosis genes were analyzed by quantitative polymerase chain reaction and Western blot. RESULTS: The CUR dose-dependently reduced the proliferation and lipid accumulation of PSPA. Noncytotoxic doses of CUR (10 to 20 µM) significantly inhibited extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and expression of adipogenic genes peroxisome proliferation-activity receptor-γ (PPAR-γ), CCAAT/enhancer binding protein-α, sterol regulatory element-binding protein-1c, adipocyte protein-2, glucose transporter-4 as well as key lipogenic enzymes fatty acid synthase and acetyl-CoA carboxylase, while ERK1/2 activation significantly reversed CUR-reduced lipid accumulation by increasing PPAR-γ. Furthermore, compared with differentiation induced media treated cells, higher dose of CUR (30 µM) significantly decreased the expression of AKT and B-cell lymphoma-2 (BCL2), while increased the expression of BCL-2-associated X (BAX) and the BAX/BCL-2 expression ratio, suggesting triggered apoptosis by inactivating AKT and increasing BAX/BCL-2 ratio and Caspase-3 expression. Moreover, AKT activation significantly rescued CUR inhibiting lipid accumulation via repressing apoptosis. CONCLUSION: These results demonstrate that CUR is capable of suppressing differentiation by inhibiting ERK1/2-PPAR-γ signaling pathway and triggering apoptosis via decreasing AKT and subsequently increasing BAX/BCL-2 ratio and Caspase-3, suggesting that CUR provides an important method for the reduction of porcine body fat, as well as the prevention and treatment of human obesity.

7.
Food Res Int ; 145: 110412, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34112415

RESUMEN

Modified atmosphere packaging (MAP) is widely applied in packaging meat and meat products. While most studies had employed culture-dependent microbiological analyses or polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), the recent application of high-throughput sequencing (HTS) has been effective and reliable in detecting the microbial consortium associated with food spoilage. Since MAP application is limited in China, applying HTS in assessing the microbial consortium of meat and meat products in the country becomes imperative. In this study, quality indexes and bacterial enumeration often used as spoilage indicators were employed to assess MAP fresh pork under chilled (4 °C) storage for 21 d. The results indicated that 70%O2/30%CO2 (Group A) retained more redness (a*) content, while 70%N2/30%CO2 (Group B) markedly reduced spoilage indicators compared to the control group. Notably, high-throughput sequencing indicated that Group B and 20%O2/60%N2/20%CO2 (Group C) inhibited the growth of abundant spoilers, Pseudomonas spp. and Brochothrix spp. Thus, MAP (Group B and C) has promising potential in inhibiting predominant meat spoilers during chilled storage. This study provides valuable information to food industries on the potential application of MAP to control meat spoilage in Chinese markets.


Asunto(s)
Carne de Cerdo , Carne Roja , Animales , Atmósfera , China , Embalaje de Alimentos , ARN Ribosómico 16S , Porcinos
9.
Thorac Cancer ; 11(8): 2146-2154, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32627360

RESUMEN

BACKGROUND: The purpose of this study was to investigate the risk factors of postoperative complications and reliable prognostic factors of long-term survival in HIV-infected patients with non-small cell lung cancer (NSCLC). METHODS: HIV-infected patients with NSCLC who underwent surgical treatment were retrospectively studied; a single-institutional analysis was conducted from November 2011 to August 2018. Pre- and postoperative clinical data, including age, gender, smoking history, highly active antiretroviral therapy (HAART), CD4+ T cell count, HIV viral load, cancer histology, clinical and pathological stage (p-stage), surgical result, Glasgow Prognostic Score (GPS), the Charlson comorbidity index (CCI), survival time and postoperative complications were collected. RESULTS: A total of 33 HIV-infected patients with NSCLC were enrolled of which 18 (54.7%) had preoperative comorbidities and postoperative complications were observed in 22 (66.7%) patients. Thirty-day mortality was not observed in these patients. Median survival time after surgery was 65 months: the MST of p-stage I patients was 65 months; p-stage II MST was unestimable; p-stage III MST was 21 months. Univariate analyses showed that postoperative complications were associated with HIV viral load (P = 0.002), CCI (P = 0.027), HAART (P = 0.028) and CD4+ T cell count (P = 0.045). However, multiple logistic regression analysis showed no correlation between HAART and postoperative complications. The p-stage was an independent prognostic factor for survival time. CONCLUSIONS: In our single-arm retrospective analysis, the risk factors for postoperative complications in HIV-infected patients with NSCLC were HIV viral load, CCI and CD4+ T cell counts. The p-stage was a predictive factor for long-term survival.


Asunto(s)
Infecciones por VIH/complicaciones , Neoplasias Pulmonares/cirugía , Adulto , Anciano , Femenino , Infecciones por VIH/mortalidad , Infecciones por VIH/patología , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos , Factores de Riesgo , Análisis de Supervivencia
10.
Ann Clin Lab Sci ; 49(6): 770-776, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31882428

RESUMEN

OBJECTIVE: To study the effects of Pim-3 on lung adenocarcinoma A549 cells. A549 cells were divided into an untreated group (without any treatment), a scramble siRNA group (transfected with control siRNA), and a Pim-3-deficient group (transfected with Pim-3 siRNA). METHODS: Pim-3-deficient cells are the experimental sample, whereas scramble siRNA and untreated cells are the corresponding negative controls. Western blotting was performed to detect the expression levels of Pim-3 protein, the phosphorylation of signal transducer and activator of transcription 3 (STAT3), and the expression levels of downstream target genes (p21, cyclin D1, Bcl-2, and Bax). Flow cytometry was performed to analyze cell cycle and apoptosis. RESULTS: In the Pim-3-deficient group, Pim-3 was downregulated, the STAT3 phosphorylation level decreased, the levels of cyclin D1 and Bcl-2 decreased, but the levels of p21 and Bax increased. Meanwhile, cell proliferation was significantly inhibited (P<0.05); specifically, the G0/G1-phase cell proportion increased, whereas the S-phase cell proportion decreased and the proportion of early apoptotic cells increased significantly (P<0.05). CONCLUSION: The downregulation of Pim-3 was closely related to the activation status of the lung STAT3 signaling pathway, mediated cell proliferation inhibition and induced apoptosis.


Asunto(s)
Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas/metabolismo , Factor de Transcripción STAT3/metabolismo , Células A549 , Adenocarcinoma del Pulmón/metabolismo , Adenocarcinoma del Pulmón/patología , Apoptosis/genética , Ciclo Celular/genética , Proliferación Celular/genética , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Fosforilación
11.
Food Funct ; 10(5): 2935-2946, 2019 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-31070649

RESUMEN

In the present study, we aimed to investigate the therapeutic mechanisms of carrot juice fermented with Lactobacillus rhamnosus GG (LGG) on type 2 diabetic mellitus (T2DM) based on the regulation of gut microbiota. Carrot juice fermented with LGG was enriched with free phenols, organic acids and short-chain fatty acids (SCFAs). Supplementation of carrot juice fermented with LGG (DFCL) could favorably regulate blood glucose, insulin, antioxidant capacity and morphology of the pancreas and kidney in the diabetic rats, accompanied by an increase of SCFAs in the cecum. Furthermore, high-throughput sequencing (HTS) analysis revealed that DFCL supplementation altered the composition of gut microbiota, showing increased relative abundances of functionally relevant enterotypes, such as Christensenellaceae_R-7_group, Oscillibacter, Ruminococcaceae_UCG-013, Lachnospiraceae_NK4A136_group and Akkermansia. In addition, Spearman's correlation analysis revealed that Desulfovibrio, Ruminococcaceae and Alloprevotella were closely correlated with biochemical biomarkers. Meanwhile, DFCL treatment regulated the expressions of genes involved in glucose metabolism at the mRNA and protein levels.


Asunto(s)
Daucus carota/metabolismo , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/microbiología , Alimentos Fermentados/análisis , Jugos de Frutas y Vegetales/análisis , Microbioma Gastrointestinal , Animales , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/metabolismo , Glucemia/metabolismo , Ciego/microbiología , Daucus carota/química , Daucus carota/microbiología , Diabetes Mellitus Tipo 2/metabolismo , Ácidos Grasos Volátiles/metabolismo , Alimentos Fermentados/microbiología , Jugos de Frutas y Vegetales/microbiología , Humanos , Insulina/metabolismo , Lacticaseibacillus rhamnosus/metabolismo , Masculino , Ratas , Ratas Wistar
12.
Front Biosci (Elite Ed) ; 10(3): 461-468, 2018 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-29772519

RESUMEN

Chemoresistance is a critical obstacle to the treatment of hepatocellular carcinoma (HCC). The mechanisms underlying resistance to doxorubicin, cisplatin, and 5-fluorouracil involve p53 and P-glycoprotein (P-gp). p53 plays a role in cell growth; therefore, resistance mechanisms involve chemotherapy-induced apoptosis and p53 mutation and inactivation. P-gp is an energy-dependent drug efflux pump regulated by p53. Its role in drug resistance has provided new insights into the mechanisms underlying the involvement of p53 and P-gp in chemoresistance and may alter our traditional understanding of p53 and P-gp function. This review outlines the roles and principal mechanisms of p53 and P-gp mediated chemoresistance in HCC.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/fisiología , Carcinoma Hepatocelular/genética , Resistencia a Antineoplásicos/genética , Genes p53 , Neoplasias Hepáticas/genética , Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Humanos , Neoplasias Hepáticas/tratamiento farmacológico
13.
Plant J ; 91(4): 714-724, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28502081

RESUMEN

Wheat (Triticum aestivum L.) incurs significant yield losses from powdery mildew, a major fungal disease caused by Blumeria graminis f. sp. tritici (Bgt). enhanced disease resistance1 (EDR1) plays a negative role in the defense response against powdery mildew in Arabidopsis thaliana; however, the edr1 mutant does not show constitutively activated defense responses. This makes EDR1 an ideal target for approaches using new genome-editing tools to improve resistance to powdery mildew. We cloned TaEDR1 from hexaploid wheat and found high similarity among the three homoeologs of EDR1. Knock-down of TaEDR1 by virus-induced gene silencing or RNA interference enhanced resistance to powdery mildew, indicating that TaEDR1 negatively regulates powdery mildew resistance in wheat. We used CRISPR/Cas9 technology to generate Taedr1 wheat plants by simultaneous modification of the three homoeologs of wheat EDR1. No off-target mutations were detected in the Taedr1 mutant plants. The Taedr1 plants were resistant to powdery mildew and did not show mildew-induced cell death. Our study represents the successful generation of a potentially valuable trait using genome-editing technology in wheat and provides germplasm for disease resistance breeding.


Asunto(s)
Ascomicetos/fisiología , Resistencia a la Enfermedad/genética , Edición Génica , Enfermedades de las Plantas/inmunología , Triticum/genética , Secuencia de Aminoácidos , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , Silenciador del Gen , Enfermedades de las Plantas/microbiología , Hojas de la Planta , Poliploidía , Alineación de Secuencia , Triticum/citología , Triticum/inmunología , Triticum/microbiología
14.
Opt Express ; 24(2): 1008-16, 2016 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-26832483

RESUMEN

We propose a new scheme of the resonant four-wave mixing (FWM) for the frequency up or down conversion, which is more efficient than the commonly-used scheme of the non-resonant FWM. In this new scheme, two control fields are spatially varied such that a probe field at the input can be converted to a signal field at the output. The efficiency of probe-to-signal energy conversion can be 90% at medium's optical depth of about 100. Our proposed scheme works for both the continuous-wave and pulse cases, and is flexible in choosing the control field intensity. This work provides a very useful tool in the nonlinear frequency conversion.

15.
Environ Toxicol ; 31(12): 1720-1730, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26218639

RESUMEN

The objective of this study is to understand the impairment of learning and memory in mouse after chronic nitrite exposure. The animal model of nitrite exposure in mouse was created with the daily intubation of nitrite in adult healthy male mice for 3 months. Furthermore, the mouse's learning and memory abilities were tested with Morris water maze, and the expression of Synaptophysin and γ-Synuclein was visualized with immunocytochemistry and Western blot. Our results showed that nitrite exposure significantly prolonged the escape latency period (ELP) and decreased the values of the frequency across platform (FAP) as well as the accumulative time in target quadrant (ATITQ) compared to control, in dose-dependent manner. In addition, after nitrite exposure, synaptophysin (SYN) positive buttons in the visual cortex was reduced, in contrast the increase of γ-synuclein positive cells. The results above were supported by Western blot as well. We conclude that nitrite exposure could lead to a decline in mice's learning and memory. The overexpression of γ-synuclein contributed to the synaptic loss, which is most likely the cause of learning and memory impairment. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1720-1730, 2016.


Asunto(s)
Aprendizaje/efectos de los fármacos , Memoria/efectos de los fármacos , Nitritos/toxicidad , Sinapsis/efectos de los fármacos , Animales , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Ratones Endogámicos C57BL , Sinapsis/metabolismo , Sinapsis/ultraestructura , Sinaptofisina/metabolismo , Sinucleínas/metabolismo , Corteza Visual/efectos de los fármacos , Corteza Visual/metabolismo , Corteza Visual/ultraestructura
16.
Front Biosci (Landmark Ed) ; 21(5): 998-1005, 2016 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-26709755

RESUMEN

Lung cancer causes the most number of deaths from cancer. Non-small cell lung cancer (NSCLC), including squamous cell carcinoma, large cell carcinoma, and adenocarcinoma, is responsible for more than 80% of primary lung cancer cases. As metastasis is the main cause of death, understanding the mechanisms underlying NSCLC metastasis are essential for improving the treatment of this disease. Recent studies have found that microRNAs (miRNAs) are involved in the progression from cell invasion and migration to final tumor metastasis of NSCLC. In this review, we will discuss the role and mechanisms of miRNAs related to the metastasis of NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/patología , MicroARNs/genética , Metástasis de la Neoplasia/genética , Humanos , Neoplasias Pulmonares/genética
17.
Angew Chem Int Ed Engl ; 54(49): 14723-7, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26474079

RESUMEN

The replacement of platinum with non-precious-metal electrocatalysts with high efficiency and superior stability for the hydrogen-evolution reaction (HER) remains a great challenge. Herein, we report the one-step synthesis of uniform, ultrafine molybdenum carbide (Mo2C) nanoparticles (NPs) within a carbon matrix from inexpensive starting materials (dicyanamide and ammonium molybdate). The optimized catalyst consisting of Mo2C NPs with sizes lower than 3 nm encapsulated by ultrathin graphene shells (ca. 1-3 layers) showed superior HER activity in acidic media, with a very low onset potential of -6 mV, a small Tafel slope of 41 mV dec(-1), and a large exchange current density of 0.179 mA cm(-2), as well as good stability during operation for 12 h. These excellent properties are similar to those of state-of-the-art 20% Pt/C and make the catalyst one of the most active acid-stable electrocatalysts ever reported for HER.

18.
Yi Chuan ; 35(8): 1023-9, 2013 Aug.
Artículo en Chino | MEDLINE | ID: mdl-23956091

RESUMEN

The antimicrobial peptides (AMPs) exhibit a broad antimicrobial spectrum. The application of AMPs from non-plant organisms attracts considerable attention in plant disease resistance engineering. Ponericin W1, isolated from the venom of ant (Pachycondyla goeldii), shows antimicrobial activities against Gram-positive bacteria, Gram-negative bacteria and the budding yeast (Saccharomyces cerevisiae); however, it is not clear whether Ponericin W1 is effective against plant pathogens. The results of this study indicated synthesized Ponericin W1 inhibited mycelial growth of Magnaporthe oryzae and Botrytis cinerea, as well as hyphal growth and spore production of Fusarium graminearum. Besides, Ponericin W1 exhibited antibacterial activities against Pseudomonas syringae pv. tomato and Xanthomonas oryzae pv. oryzae. After codon optimization, Ponericin W1 gene was constructed into plant expression vector, and transformed into Arabidopsis thaliana by floral dip method. The Ponericin W1 was located in intercellular space of the transgenic plants as expected. Compared with the wild-type plants, there were ungerminated spores and less hyphal, conidia on the leaves of transgenic plants after innoculation with the powdery mildew fungus Golovinomyces cichoracearum. After innoculation with the pathogenic bac-terium Pseudomonas syringae pv. tomato, the baceria in the leaves of transgenic plants was significantly less than the wild-type plants, indicating that the transgenic plants displayed enhanced disease resistance to pathogens. These results demonstrate a potential use of Ponericin W1 in genetic engineering for broad-spectrum plant disease resistance.


Asunto(s)
Arabidopsis , Resistencia a la Enfermedad , Animales , Antiinfecciosos , Hormigas , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas , Enfermedades de las Plantas/genética , Hojas de la Planta/genética , Plantas Modificadas Genéticamente/genética
19.
Gene ; 527(1): 235-42, 2013 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-23820081

RESUMEN

Thanatin(S) is an analog of thanatin, an insect antimicrobial peptide possessing strong and broad spectrum of antimicrobial activity. In order to investigate if the thanatin could be used in engineering transgenic plants for increased resistance against phytopathogens, the synthetic thanatin(S) was introduced into Arabidopsis thaliana plants. To increase the expression level of thanatin(S) in plants, the coding sequence was optimized by plant-preference codon. To avoid cellular protease degradation, signal peptide of rice Cht1 was fused to N terminal of thanatin(S) for secreting the expressed thanatin(S) into intercellular spaces. To evaluate the application value of thanatin(S) in plant disease control, the synthesized coding sequence of Cht1 signal peptide (Cht1SP)-thanatin(S) was ligated to plant gateway destination binary vectors pGWB11 (with FLAG tag). Meanwhile, in order to observe the subcellular localization of Cht1SP-thanatin(S)-GFP and thanatin(S)-GFP, the sequences of Cht1SP-thanatin(S) and thanatin(S) were respectively linked to pGWB5 (with GFP tag). The constructs were transformed into Arabidopsis ecotype Col-0 and mutant pad4-1 via Agrobacterium-mediated transformation. The transformants with Cht1SP-thanatin(S)-FLAG fusion gene were analyzed by genomic PCR, real-time PCR, and western blots and the transgenic Arabidopsis plants introduced respectively Cht1SP-thanatin(S)-GFP and thanatin(S)-GFP were observed by confocal microscopy. Transgenic plants expressing Cht1SP-thanatin(S)-FLAG fusion protein showed antifungal activity against Botrytis cinerea and powdery mildew, as well as antibacterial activity against Pseudomonas syringae pv. tomato. And the results from confocal observation showed that the GFP signal from Cht1SP-thanatin(S)-GFP transgenic Arabidopsis plants occurred mainly in intercellular space, while that from thanatin(S)-GFP transgenic plants was mainly detected in the cytoplasm and that from empty vector transgenic plants was distributed uniformly throughout the cell, demonstrating that Cht1 signal peptide functioned. In addition, thanatin(S) and thanatin(S)-FLAG chemically synthesized have both in vitro antimicrobial activities against P. syringae pv. tomato and B. cinerea. So, thanatin(S) is an ideal candidate AMPs for the construction of transgenic crops endowed with a broad-spectrum resistance to phytopathogens and the strategy is feasible to link a signal peptide to the target gene.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/biosíntesis , Arabidopsis/genética , Proteínas de Insectos/biosíntesis , Enfermedades de las Plantas/microbiología , Plantas Modificadas Genéticamente/genética , Arabidopsis/metabolismo , Arabidopsis/microbiología , Botrytis/fisiología , Quitinasas/química , Resistencia a la Enfermedad , Proteínas Fluorescentes Verdes/biosíntesis , Interacciones Huésped-Patógeno , Microscopía Fluorescente , Oryza/enzimología , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/microbiología , Proteínas de Plantas/química , Plantas Modificadas Genéticamente/metabolismo , Plantas Modificadas Genéticamente/microbiología , Señales de Clasificación de Proteína , Pseudomonas syringae/fisiología , Proteínas Recombinantes de Fusión/biosíntesis , Esporas Fúngicas/fisiología
20.
Plant Cell ; 25(3): 1143-57, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23532072

RESUMEN

Pathogen-associated molecular pattern (PAMP)-trigged immunity (PTI) is the first defensive line of plant innate immunity and is mediated by pattern recognition receptors. Here, we show that a mutation in BR-SIGNALING KINASE1 (BSK1), a substrate of the brassinosteroid (BR) receptor BRASSINOSTEROID INSENSITIVE1, suppressed the powdery mildew resistance caused by a mutation in ENHANCED DISEASE RESISTANCE2, which negatively regulates powdery mildew resistance and programmed cell death, in Arabidopsis thaliana. A loss-of-function bsk1 mutant displayed enhanced susceptibility to virulent and avirulent pathogens, including Golovinomyces cichoracearum, Pseudomonas syringae, and Hyaloperonospora arabidopsidis. The bsk1 mutant also accumulated lower levels of salicylic acid upon infection with G. cichoracearum and P. syringae. BSK1 belongs to a receptor-like cytoplasmic kinase family and displays kinase activity in vitro; this kinase activity is required for its function. BSK1 physically associates with the PAMP receptor FLAGELLIN SENSING2 and is required for a subset of flg22-induced responses, including the reactive oxygen burst, but not for mitogen-activated protein kinase activation. Our data demonstrate that BSK1 is involved in positive regulation of PTI. Together with previous findings, our work indicates that BSK1 represents a key component directly involved in both BR signaling and plant immunity.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Inmunidad de la Planta , Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Sustitución de Aminoácidos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Arabidopsis/microbiología , Proteínas de Arabidopsis/genética , Ascomicetos/inmunología , Ascomicetos/patogenicidad , Brasinoesteroides/metabolismo , Membrana Celular/metabolismo , Senescencia Celular , Resistencia a la Enfermedad , Activación Enzimática , Etilenos/farmacología , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Complejos Multiproteicos/genética , Complejos Multiproteicos/metabolismo , Fenotipo , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/microbiología , Mutación Puntual , Proteínas Quinasas/genética , Proteínas Serina-Treonina Quinasas/genética , Especies Reactivas de Oxígeno/metabolismo , Ácido Salicílico/metabolismo , Transducción de Señal , Nicotiana/genética , Nicotiana/metabolismo
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