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

Banco de datos
Tipo del documento
País de afiliación
Intervalo de año de publicación
1.
Int Arch Allergy Immunol ; 176(3-4): 255-267, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29874664

RESUMEN

BACKGROUND: The balance between T helper 17 (Th17) and regulatory T cells (Treg) is a new paradigm in asthma pathogenesis, but no therapeutic targets could modulate the Th17/Treg balance specifically for asthma. Since previous studies have shown the programmed cell death-1(PD-1)/PD-ligand 1 (PD-L1) pathway is critical to immune homeostasis in this disease, we hypothesized that the PD-1/PD-L1 pathway might be involved in the regulation of Treg/Th17 imbalance in asthmatic children. METHODS: The percentage of Treg and Th17 cells and the expression of PD-1 and PD-L1 were detected by flow cytometry in children with asthma and healthy controls. CD4+ T cells were stimulated with Th17 and Treg differentiating factors, and treated with anti-PD-1. Then cells were harvested and measured for Th17 and Treg percentages and Foxp3 and RORγt levels using RT-PCR. RESULTS: We observed an inverse correlation between the percentages of Treg and Th17 cells, and the expression of PD-1 and PD-L1 in the two subsets also changed in the mild persistent and moderate to severe persistent groups compared with healthy controls. In vitro, administration of anti-PD-1 could decrease Th17 percentages and RORγt mRNA, and increase Treg percentages and Foxp3 mRNA in CD4+ T cells of children with asthma in the mild persistent and moderate to persistent groups. Additionally, the role played by anti-PD-1 in regulating Treg/Th17 balance was further confirmed in an asthmatic mouse model. CONCLUSION: Alteration of the PD-1/PD-L1 pathway can modulate Treg/Th17 balance in asthmatic children. Treatment with anti-PD-1 posed protective effects on asthma models, providing a novel theoretical target for asthma.


Asunto(s)
Asma/inmunología , Antígeno B7-H1/fisiología , Receptor de Muerte Celular Programada 1/fisiología , Transducción de Señal/fisiología , Linfocitos T Reguladores/inmunología , Células Th17/inmunología , Animales , Células Cultivadas , Niño , Preescolar , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores
2.
J Cancer Res Ther ; 17(3): 695-701, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34269301

RESUMEN

OBJECTIVES: The aim of the study was to compare the relative diagnostic utility of low-dose computed tomography (LDCT) and standard-dose computed tomography (SDCT)-guided lung biopsy approaches. MATERIALS AND METHODS: The PubMed, Embase, and Cochrane Library databases were searched for relevant studies published through August 2020. Data pertaining to endpoints including technical success, diagnostic performance, operative time, radiation dose, and complications, were extracted, and meta-analysis was performed using RevMan v5.3. RESULTS: Three retrospective analyses and three randomized controlled trials, were included. The studies included 1977 lung lesions across 1927 patients who underwent LDCT-guided lung biopsy, and 887 lung lesions across 879 patients who underwent SDCT-guided lung biopsy. No significant differences were observed between these LDCT and SDCT groups with respect to the rates of technical success (99.0% vs. 99.5%, odds ratio [OR]: 1.82, P = 0.35,), diagnostic yield (79.6% vs. 76.2%, OR: 0.93, P = 0.47), diagnostic accuracy (96.1% vs. 96.1%, OR: 0.93, P = 0.69), operative time (mean difference [MD]: 1.04, P = 0.30), pneumothorax (19.9% vs. 21.3%, OR: 0.92, P = 0.43) or hemoptysis (4.6% vs. 5.8%, OR: 1.14, P = 0.54). Patients in the LDCT group received a significantly lower radiation dose (MD: ‒209.87, P < 0.00001) than patients in the SDCT group. Significant heterogeneity was observed with respect to the operative duration and radiation dose endpoints (I2 = 84% and 100%, respectively). CONCLUSIONS: Relative to SDCT-guided lung biopsy, an LDCT-guided approach is equally safe and can achieve comparable diagnostic efficacy while exposing patients to lower doses of radiation.


Asunto(s)
Neoplasias Pulmonares/diagnóstico , Pulmón/patología , Tomografía Computarizada por Rayos X/efectos adversos , Humanos , Biopsia Guiada por Imagen/efectos adversos , Biopsia Guiada por Imagen/métodos , Biopsia Guiada por Imagen/estadística & datos numéricos , Pulmón/diagnóstico por imagen , Neoplasias Pulmonares/patología , Dosis de Radiación , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/estadística & datos numéricos
3.
Plant Cell Rep ; 28(8): 1205-13, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19504262

RESUMEN

Economically important compounds, such as licorice flavonoids, are present in insufficient amounts in the hairy roots. To overcome this problem, we took the transgenic approach combined with the elicitation technique to increase the flavonoid production. The Glycyrrhiza uralensis Fisch cDNA encoding chalcone isomerase gene (chi) was over-expressed in hairy roots of G. uralensis Fisch mediated by the disarmed Agrobacterium rhizogenes A4. Stable genetic transformation was confirmed by Southern blot analysis. The transgenic and wild cultures were subsequently elicited with PEG8000 (2%) alone, yeast extract (YE) (0.1%) alone, or both of them, and then the total flavonoids were extracted and measured. The results showed that over a culture period of 3 weeks, the wild-type hairy roots, the untreated transgenic hairy roots, and the double-treated transgenic hairy roots accumulated 0.842, 1.394, and 2.838 (g/100 g DW) of total flavonoids, respectively. Moreover, the enhanced accumulation of flavonoids were correlated with the elevated level of chi transcripts and CHI activity, confirming the key role of chi in the flavonoids synthesis. This research demonstrated that the combination of the metabolic engineering and PEG8000-YE elicitation treatment was an effective strategy to increase the flavonoids production in hairy roots of G. uralensis Fisch.


Asunto(s)
Flavonoides/biosíntesis , Glycyrrhiza uralensis/enzimología , Liasas Intramoleculares/metabolismo , Proteínas de Plantas/metabolismo , Raíces de Plantas/enzimología , Agrobacterium tumefaciens/genética , ADN Complementario/genética , ADN de Plantas/genética , Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Glycyrrhiza uralensis/genética , Liasas Intramoleculares/genética , Proteínas de Plantas/genética , Raíces de Plantas/genética , Plantas Modificadas Genéticamente/enzimología , Plantas Modificadas Genéticamente/genética , Transformación Genética
4.
Yi Chuan ; 31(6): 663-7, 2009 Jun.
Artículo en Zh | MEDLINE | ID: mdl-19586868

RESUMEN

The AGPL1 (ADP-glucose pyrophosphorylase large subunit 1) promoter from watermelon (Citrullus vulgaris S.) has proved to exhibit fruit-specific expression patterns in tomato (Lycopersicon esculentum L.). A plant expression vector harboring sweet-taste protein, Brazzein, directed by AGPL1 promoter, was constructed and transferred into tomato plants through Agrobacterium-mediated transform methods. Histochemical staining assay, PCR screening, Southern blotting analysis and RT-PCR analysis showed that Brazzein gene was successfully integrated into the genome of transgenic tomato plants with stable expression. Sweet-taste fruits were produced under control of fruit-specific AGPL1 promoter, whereas other parameters of fruit quality were largely unchanged.


Asunto(s)
Benzopiranos/metabolismo , Frutas/metabolismo , Vectores Genéticos/genética , Indenos/metabolismo , Plantas Modificadas Genéticamente/metabolismo , Solanum lycopersicum/genética , Southern Blotting , Citrullus/genética , Frutas/genética , Genes de Plantas/genética , Solanum lycopersicum/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Modificadas Genéticamente/genética , Rhizobium/genética , Transfección
5.
Curr Med Sci ; 39(3): 391-395, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31209808

RESUMEN

Overcrowding and cell deformation lead to the shedding of apoptotic and live cells to maintain homeostasis in the epithelium. Recent studies have attempted to explain the effect of extrusion on epithelial homeostasis and tumor metastasis, but lack the requisite quantitative models for testing extrusion. Here, we designed a petri dish inversion model to detect the extrusion ability of both normal epithelial cells and epithelial cancer cells. Firstly, we found cell extrusion was observed in both normal epithelial cells (LO2 cells) and cancer cells; in confluent LO2 cell culture, certain cells were surrounded by their neighbors, suffered "collective attack", and were then made round in shape. Green fluorescent protein (GFP)-labeled cancer cells were also found to be squeezed by normal LO2 cells. Using the petri dish inversion model, we quantified the number of extrusion cells, and demonstrated that the ability of cancer cell extrusion was related to the metastatic potential of cancer cell lines. Our findings provide a novel model to detect crowding-induced epithelial cell and cancer cell extrusion. This novel model provides a quantitative method for research into apoptotic and cancer cell extrusion, particularly in human hepatocellular carcinoma.


Asunto(s)
Movimiento Celular , Hepatocitos/patología , Modelos Biológicos , Apoptosis , Fenómenos Biomecánicos , Recuento de Células , Línea Celular , Línea Celular Tumoral , Homeostasis/fisiología , Humanos
6.
FEBS Lett ; 580(5): 1303-8, 2006 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-16457823

RESUMEN

Four AP2/EREBP genes encoding putative ethylene-responsive element binding factor (ERF)/AP2 domains were cloned from Brassica napus, and these genes could be induced by low temperature, ethylene, drought, high salinity, abscisic acid and jasmonate treatments. These four genes, named BnDREBIII-1 to BnDREBIII-4, were highly homologous and the 37th amino acid was the only difference among their ERF/AP2 domains. BnDREBIII-1 was demonstrated to be able to bind to both dehydration-responsive element and the GCC box and transactivate the expression of downstream genes, while BnDREBIII-4 could bind neither. Further results suggested that Ala37 might play a crucial role in the DNA binding or the stability of the ERF/AP2 domain.


Asunto(s)
Brassica napus/genética , Secuencia Conservada , Regulación de la Expresión Génica de las Plantas , Proteínas de Homeodominio/metabolismo , Proteínas Nucleares/metabolismo , Proteínas de Plantas/metabolismo , Elementos de Respuesta , Ácido Abscísico , Adaptación Fisiológica/genética , Alanina , Sitios de Unión , Ciclopentanos , ADN de Plantas , Proteínas de Unión al ADN , Deshidratación , Etilenos , Proteínas de Homeodominio/química , Proteínas Nucleares/química , Oxilipinas , Proteínas de Plantas/química , Regiones Promotoras Genéticas , Sales (Química) , Semillas/genética , Factores de Transcripción
7.
Hepatobiliary Pancreat Dis Int ; 4(3): 433-6, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16109531

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common cancer-related causes of death worldwide. The epidermal growth factor receptor (EGFR) is highly expressed in many human tumors and provides a new target for anticancer drug development. The aim of the present study was to explore the effect of EGFR antisense oligodeoxynucleotide on human HCC. METHODS: SMMC-7721 cells in culture were treated with 10 mumol/L antisense-odn for 24, 48, 72 hours respectively and MTT assay was adopted to determine the proliferation of tumor cells in vitro. About 2 x 10(6) SMMC-7721 cells with or without pretreatment(30 micromol/L oligodeoxynucleotide) were inoculated into subcutaneous flap of 21 nude mice, of which 7 were treated with EGFR antisense-odn, 7 with scrambled oligodeoxynucleotide (scrambled-odn), and 7 not treated in vivo. RESULTS: In vitro, after 24, 48, 72 hours the inhibitory rate of proliferation of SMMC-7721 cells treated with EGFR antisense-odn was 8%, 32%, and 34% respectively. In vivo after 8 weeks, no palpable tumor was found in 1/7 mice receiving cells pretreated with antisense-odn, whereas 7/7 untreated mice and 6/7 mice treated with scrambled-odn developed palpable tumors. Tumor growth in antisense-odn treated mice was significantly inhibited in comparison with that of those untreated (P < 0.01) or treated with scrambled-odn (P < 0.05). CONCLUSIONS: Antisense oligodeoxynucleotide acts as a specific growth inhibitor on SMMC-7721 in a sequence specific and time-dependent manner. EGFR antisense-odn can significantly inhibit the proliferation of human hepatoma cell in vitro as well as in vivo, indicating that EGFR may play an important role in the development of hepatoma and will be a new target for its treatment.


Asunto(s)
Carcinoma Hepatocelular/patología , Receptores ErbB/genética , Neoplasias Hepáticas Experimentales/patología , Neoplasias Hepáticas Experimentales/prevención & control , Neoplasias Hepáticas/patología , Oligonucleótidos Antisentido/farmacología , Animales , División Celular/efectos de los fármacos , Línea Celular Tumoral , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Trasplante de Neoplasias
8.
Zhonghua Gan Zang Bing Za Zhi ; 12(1): 35-7, 2004 Jan.
Artículo en Zh | MEDLINE | ID: mdl-14761281

RESUMEN

OBJECTIVE: To investigate the inhibitory effects of antisense oligonucleotides to different sequences on VEGF gene expression by human hepatoma cells. METHODS: SMMC7721 cells were cultured under normoxic or hypoxic conditions for 24 h, followed by being transfected with different antisense oligonucleotides (A06513 to cap structure, A06514 to translation initiation, A06515 to Exon-3 and A06516 to translation terminal). The total RNAs from the cells were extracted and the VEGF expression were examined with RT-PCR. The relative concentrations of VEGF transcripts in SMMC772 cells from different groups were determined using GAPDH (glyceraldehyde-3-phosphate dehydrogenase) cDNA as internal standard. RESULTS: In response to the hypoxic challenge, SMMC7721 cells upregulated VEGF mRNA; Comparative to the control (no oligonucleotides), A06513, A06514, A06515, and A06516 had obvious sequence-specific inhibitory effect on VEGF gene expression, with the ratio of VEGF over GAPDH of 0.49+/-0.08, 0.71+/-0.12, 0.72+/-0.11 and 0.86+/-0.12, respectively (F=12.21, P< 0.05). A06513 showed the strongest inhibitory effect (P<0.01). CONCLUSION: The antisense oligonucleotides complementary to VEGF cap structure, may become a potential alternative for antisense gene therapy of HCC.


Asunto(s)
Neoplasias Hepáticas/terapia , Oligonucleótidos Antisentido/farmacología , Factor A de Crecimiento Endotelial Vascular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores
9.
Int J Clin Exp Pathol ; 7(9): 6307-12, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25337284

RESUMEN

Carbohydrate antigen 19-9 (CA19-9) is the most frequently applied serum tumor marker for diagnosis of cancers in the digestive organs. However, some patients with benign diseases can have elevated serum levels of CA19-9 as well. The current study presents a 55-year-old female who was admitted to our hospital for further evaluation of a nodular cavity shadow in the right lower lobe and clarification of the cause of the marked elevation of serum CA19-9 levels. Abdominal MRI and gastrointestinal endoscopy did not find any malignancy. As lung cancer cannot be excluded in this patient, a video-assisted thoracoscopic surgery was carried, intraoperative and postoperative biopsy analysis both suggested chronic bronchitis with fungal infection (due to Histoplasma capsulatum or Penicillium marneffei) and organization. Immunohistochemistry showed marked positive staining for CA19-9 in the damaged lung tissue. The CA19-9 levels quickly returned to the normal range following lobe resection. Therefore, the marked elevation of serum CA19-9 levels, in this case, may have resulted from the chronic bronchitis with fungal infection.


Asunto(s)
Bronquitis Crónica/sangre , Antígeno CA-19-9/sangre , Histoplasmosis/sangre , Enfermedades Pulmonares Fúngicas/sangre , Biomarcadores/sangre , Biopsia , Bronquitis Crónica/diagnóstico , Bronquitis Crónica/microbiología , Bronquitis Crónica/cirugía , Femenino , Histoplasma/patogenicidad , Histoplasmosis/diagnóstico , Histoplasmosis/microbiología , Histoplasmosis/cirugía , Humanos , Inmunohistoquímica , Enfermedades Pulmonares Fúngicas/diagnóstico , Enfermedades Pulmonares Fúngicas/microbiología , Enfermedades Pulmonares Fúngicas/cirugía , Persona de Mediana Edad , Penicillium/patogenicidad , Neumonectomía/métodos , Valor Predictivo de las Pruebas , Cirugía Torácica Asistida por Video , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Regulación hacia Arriba
10.
Zhonghua Liu Xing Bing Xue Za Zhi ; 34(1): 57-60, 2013 Jan.
Artículo en Zh | MEDLINE | ID: mdl-23648252

RESUMEN

OBJECTIVE: To understand the biochemical characteristics, virulence genes and pathogenicity of Shigella flexneri Xv isolated in Beijing. METHODS: 61 strains of S. flexneri Xv isolated from diarrhea patients in Beijing were systematically determined through biochemical reactions and serological tests. Application of PCR technique in detection of virulence genes on ipaH, sen, virF, ial and pulsed-field gel electrophoresis (PFGE) was used to identify the related characteristics and on rat lung slices to determine its pathogenicity. RESULTS: All of the S. flexneri Xv could ferment glucose, mannitol, melibiose and arabinose. Using serum agglutination, we found that the antigen structure was (IV: 7, 8). IpaH, sen, virF and ial that carried rates of virulence genes appeared to be 100%, 81.97%, 75.41% and 80.30%, respectively. Among 61 strains of S. flexneri Xv, the PFGE typing of Shigella bacteria could be divided into 25 belt types while the results from rat lung slices showed inflammatory change of Xv. CONCLUSION: S. flexneri Xv was found that it carried high rate of Shigella virulence genes, exhibiting genetic polymorphism and highly invasive.


Asunto(s)
Shigella flexneri/clasificación , Shigella flexneri/patogenicidad , Virulencia/genética , Animales , Humanos , Pruebas de Sensibilidad Microbiana , Ratas , Shigella flexneri/aislamiento & purificación
12.
Mol Biotechnol ; 47(1): 50-6, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20607624

RESUMEN

We evaluated the effect of Tween 80 as elicitor on licochalcone A from hairy root cultures of Glycyrrhiza uralensis Fisch. After a 15-days treatment with 2% Tween 80, hairy roots still grew well and produced higher levels of licochalcone A and total flavonoids than the control (without treatment). Licochalcone A content and total flavonoid content were 3.103 and 127.095 mg per flask (9- and 11-fold higher), respectively, compared with controls. Secretion of licochalcone A and total flavonoids into the culture medium was remarkably high, up to 98 and 94% of the total production, respectively. The enhanced flavonoid production was associated with elevated mRNA levels and enzyme activities of phenylalanine ammonia-lyase (PAL), 4-coumarate:coenzyme A ligase (4CL), and cinnamate-4-hydroxylase (C4H). These results clearly demonstrated that Tween 80 treatment permeabilized the roots to enhance secretion, but also acted as an efficient elicitor of licochalcone A and total flavonoid production in hairy roots of G. uralensis Fisch.


Asunto(s)
Chalconas/biosíntesis , Chalconas/metabolismo , Glycyrrhiza uralensis/metabolismo , Polisorbatos/química , Regulación hacia Arriba , Coenzima A Ligasas/metabolismo , Medios de Cultivo/metabolismo , Glycyrrhiza uralensis/crecimiento & desarrollo , Fenilanina Amoníaco-Liasa/metabolismo , Raíces de Plantas/metabolismo
14.
J Biol Chem ; 281(16): 10752-9, 2006 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-16497677

RESUMEN

DREB1/C-repeat binding factor (CBF) is a plant-specific family of transcription factors and plays a crucial role in freeze tolerance. In the present work, two groups of drought-responsive element binding factor (DREB)-like genes were isolated from Brassica napus, named Group I and Group II. The two groups of genes were both induced by low temperature, but the expression of Group I preceded that of Group II. The Group I DREBs could specifically bind with the DRE cis-acting element and activate the expression of downstream genes, but Group II factors were trans-inactive although they still had the ability to bind with DRE, which was confirmed by electrophoretic mobility shift assay. Fluorescence quenching assays indicated that the DRE binding ability of the two groups was similar. Co-expression of Group II could depress the trans-activation activity of Group I DREB in a concentration-dependent manner. These results strongly suggested that the trans-active Group I DREBs were expressed at the early stage of cold stress to open the DRE-mediated signaling pathway in cold stress, whereas the trans-inactive Group II DREBs were expressed at the later stage to close the signal pathway in a competitive manner. The results herein provide a new insight into the regulation mechanisms of the DRE-mediated signaling pathway in response to cold stress.


Asunto(s)
Brassica napus/genética , Desastres , Regulación de la Expresión Génica de las Plantas , Activación Transcripcional , Secuencia de Aminoácidos , Western Blotting , Clonación Molecular , Frío , ADN/metabolismo , ADN Complementario/metabolismo , Relación Dosis-Respuesta a Droga , Congelación , Genes de Plantas , Modelos Biológicos , Modelos Genéticos , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/metabolismo , Unión Proteica , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Aminoácido , Transducción de Señal , Temperatura , Factores de Tiempo , Técnicas del Sistema de Dos Híbridos
15.
Clin Immunol ; 119(3): 245-51, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16616877

RESUMEN

The expression of the apoptosis-inducing ligands, TNF-alpha, FasL and TRAIL on peripheral blood mononuclear cells (PBMC) and the levels of their soluble form (TNF-alpha, sFasL and sTRAIL) in plasma from 40 hemorrhagic fever with renal syndrome (HFRS) patients as well as 26 healthy blood donors were determined by flow cytometry (FCM) analysis and sandwich ELISA, respectively. The status of Th1, Th2, Tc1 and Tc2 subsets in PBMC was evaluated by intracellular cytokine staining and FCM. Compared to controls, the expression of membrane bound FasL and TRAIL was up-regulated on surface of PBMC isolated from the HFRS patients, particularly on CD8+ T lymphocytes. The levels of TNF-alpha, sFasL and sTRAIL in plasma from the HFRS patients in the acute phase increase 4.7-fold, 6.0-fold and 1.8-fold, respectively, over those from the healthy donors. The percentage of Th1, Tc1 and Tc2 subsets in PBMC from the patients also increased significantly compared with those from healthy donors. These results indicate that dynamic changes occurred in both the membrane bound and soluble forms of apoptosis-inducing ligands (FasL, TRAIL and TNF-alpha) and proportions of Th1 and CTL in HFRS patients increased. Both factors may play an important role in the etiology of Hantaan virus infection in humans.


Asunto(s)
Proteínas Reguladoras de la Apoptosis/inmunología , Apoptosis/inmunología , Fiebre Hemorrágica con Síndrome Renal/inmunología , Glicoproteínas de Membrana/inmunología , Factor de Necrosis Tumoral alfa/inmunología , Factores de Necrosis Tumoral/inmunología , Adolescente , Adulto , Anciano , Proteínas Reguladoras de la Apoptosis/sangre , Niño , Proteína Ligando Fas , Femenino , Virus Hantaan , Fiebre Hemorrágica con Síndrome Renal/sangre , Humanos , Masculino , Glicoproteínas de Membrana/sangre , Persona de Mediana Edad , Linfocitos T/inmunología , Ligando Inductor de Apoptosis Relacionado con TNF , Factor de Necrosis Tumoral alfa/análisis , Factores de Necrosis Tumoral/sangre
16.
Sheng Wu Gong Cheng Xue Bao ; 21(6): 906-10, 2005 Nov.
Artículo en Zh | MEDLINE | ID: mdl-16468344

RESUMEN

Dehydration-Responsive Element Binding ( DREB) transcription factors, specifically binding with dehydration reponsive element (DRE), activate a variety of stress-responsive genes in plants under abiotic stresses (dehydration, high salt and low temperature). Using PCR and homologous EST search, we isolated a DREB-like gene from Yinxin poplar (Populus alba x P. alba var. pyramidalis) named PaDREB2. Yeast One-hybrid experiment demonstrated that PaDREB2 protein could function as a DREB transcription factor activating target gene expression by specifically binding to DRE cis-element. To study the expression pattern of PaDREB2, RT-PCR was carried out. And the results showed that PaDREB2 is induced by low temperature, drought and high salt.


Asunto(s)
Proteínas de Plantas/metabolismo , Populus/genética , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Clonación Molecular , Frío , Sequías , Etiquetas de Secuencia Expresada , Regulación de la Expresión Génica de las Plantas , Datos de Secuencia Molecular , Filogenia , Proteínas de Plantas/genética , Populus/metabolismo , Estrés Fisiológico , Factores de Transcripción/genética
17.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 21(6): 704-6, 2005 Nov.
Artículo en Zh | MEDLINE | ID: mdl-16256031

RESUMEN

AIM: To identify the nucleocapsid protein of Hantaan virus (HTNV-NP)-specific T lymphocyte epitopes and analyze the epitope-specific T cell response during hemorrhagic fever with renal syndrome (HFRS). METHODS: T lymphocyte epitopes and frequencies of epitope-specific T cells were determined by ELISPOT using PBMCs from HFRS patients stimulated by individual or mixture of overlapping 15-mer peptides spanning the amino acid sequence of HTNV-NP. RESULTS: Out of 10 peptide mixtures, 8 elicited strong HTNV-NP-specific responses in 18 of 47 HFRS patients, and the T cell response was found at early stage of HFRS. Moreover, 17 HTNV-NP-specific T lymphocyte epitopes were identified in 11 patients, and most epitopes were clustered near the center of NP in linear structure. Among them, 14 T lymphocyte epitopes were described for the first time. CONCLUSION: HTNV-NP-specific T cell response can be elicited at early stage of HFRS and T lymphocyte epitopes mainly located in the center of NP, suggesting that it may play an important role in immune protection during HTNV infection.


Asunto(s)
Proteínas de la Cápside/inmunología , Epítopos de Linfocito T/inmunología , Virus Hantaan/inmunología , Fiebre Hemorrágica con Síndrome Renal/inmunología , Fiebre Hemorrágica con Síndrome Renal/virología , Linfocitos T/inmunología , Proteínas del Núcleo Viral/inmunología , Adolescente , Adulto , Anciano , Células Cultivadas , Niño , Femenino , Virus Hantaan/patogenicidad , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
18.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 20(6): 744-6, 2004 Nov.
Artículo en Zh | MEDLINE | ID: mdl-15555451

RESUMEN

AIM: To explore the changes of TNF, sIL-2R, IL-6, IL-4 and IFN-gamma levels in plasma from patients with hemorrhagic fever with renal syndrome(HFRS) and analyze the correlation between these cytokine levels and alanine aminotransferase(ALT) level in sera from the patients. METHODS: The cytokine levels were measured by double mAb sandwich ELISA. An automatic biochemical detector(RA-1000) was employed to determine the ALT level. RESULTS: Levels of TNF, IL-6, IL-4, IFN-gamma and sIL-2R in plasma from the patients were(95.82+/-12.04), (362.46+/-141.26), (17.76+/-3.52), (116.18+/-19.80) ng/L and (898 820+/-127 200) U/L, respectively. These cytokines in plasma from healthy donors were (17.89+/-1.68), (43.81+/-18.08), (4.86+/-1.14), (7.57+/-2.41) ng/L and (66 730+/-29 690) U/L, respectively. The cytokine levels of the patients were notably higher than those of the healthy donors.(P<0.01). At the same time, the average ALT level in sera from the patients was 4.4 fold of that from the healthy donors. Statistical analysis showed that levels of TNF, sIL-2R, IL-6 and IFN-gamma were positively correlated with ALT level, respectively. CONCLUSION: The HFRS patients have a significant increase in both cytokines (TNF, sIL-2R, IL-6 and IFN-gamma) and ALT levels. And there is a positive correlation between those cytokine and ALT levels, suggesting that the liver injury during HTNV infection may be related to the elevation of above cytokine levels.


Asunto(s)
Alanina Transaminasa/sangre , Citocinas/sangre , Fiebre Hemorrágica con Síndrome Renal/sangre , Adulto , Femenino , Humanos , Interferón gamma/sangre , Interleucina-4/sangre , Interleucina-6/sangre , Masculino , Receptores de Interleucina-2/sangre , Factores de Necrosis Tumoral/sangre
19.
Sheng Wu Gong Cheng Xue Bao ; 19(2): 227-30, 2003 Mar.
Artículo en Zh | MEDLINE | ID: mdl-15966327

RESUMEN

Fruit ripening is associated with a number of physiological and biochemical changes. They include degradation of chlorophyll, synthesis of flavor compounds, carotenoid biosynthesis, conversion of starch to sugars, cell wall solublisation and fruit softening. These changes are brought about by the expression of specific genes. People are interested in the molecular mechanism involved in the regulation of gene transcription during fruit ripening. Many fruit-specific promoters such as PG, E4, E8, and 2A11 have been characterized and shown to direct ripening-specific expression of reporter genes. AGPase plays the key role in catalyzing the biosynthesis of starch in plants. It is a heterotetrameric enzyme with two small subunits and two large subunits, which are encoded by different genes. In higher plants, small subunits are highly conserved among plant species and expressed in all tissues. And the large subunits are present at multiple isoforms and expressed in a tissue-specific pattern. In fruits, the expression pattern of the large subunits varies with plant species. That made it important to study the transcriptional regulation of the large subunits of AGPase in different plant species. Northern-blot analysis indicates in watermelon, an isoform of the large subunits Wml1 expressed specifically in fruits, not in leaves. The 5' flanking region of Wml1, which covers 1573bp, has been isolated through the method of uneven PCR. And transient expression assay has shown that the 1573bp (named WSP) can direct fruit-specific expression of GUS gene. Our goal in this study was to scan the promoter region for main regulatory regions involved in fruit-specific expression. A chimaeric gene was constructed containing the WSP promoter, the beta-glucuronidase (GUS) structural sequence as a reporter gene and the nopaline synthase polyadenylation site (NOS-ter). The plasmid pSPA was digested with Hind III + Hinc II and promoter fragment of 1573bp (from 180bp to 1752bp) was cut out and cloned into Sma I sites of pBluescript SK(-), to produce pBSPA-16. The same insert was then cut out with Hind III + BamH I, and ligated with transient expression vector pBI426 digested by HindIII + Bgl II to produce pISPA-16. Three 5'-end deletions of the promoter were obtained and fused to GUS gene in plant transient expression vector pBI426: the 1201bp fragment (from 551bp to 1752bp) was generated by digestion of pBSPA-16 with BamH I + SnaB I, the 898bp fragment (from 854bp to 1752bp) by BamH I + EcoRV. Both fragments were ligated with pBluescript SK(-) digested by BamH I + Sma I, to produce pBSPA-12 and pBS-PA-9. The inserts were cut out with HindmIII + BamH I and ligated with pBI426 digested by Hind III + Bgl II, to produce pISPA-12 and pISPA-9. The 795bp fragment (from 957bp to 1752bp) was generated by digestion of pSPA with Hinc II + EcoR I, promoter fragment was cut out and cloned into Sma I sites of pBluescript SK(-), to produce pBSPA-8. The same insert were cut out with Hind III + BamH I, and ligated with transient expression vector pBI426 digested by Hind III + Bgl II. The 1573bp fragment and three 5'-end deletions were delivered into watermelon leaf, stem, flower and fruit of different development stages (5, 10, 20 days after pollination) via particle bombardment using a biolistic PDS-1000/He particle gun. Bombardment parameters were as follows: a helium pressure of 1200 psi, vacuum of 91432.23Pa, 7 cm between the stopping screen and the plate. Histochemical assay were done on all the tissues bombarded after incubation for 2 days. The 1573bp fragment had the strongest promoter activity, and can induce GUS expression in fruits of 5 and 20 days after anthesis and flowers, but not in fruits of 10 days after anthesis, leaves and stems. Fragments of 1201bp and 898bp can induce GUS expression only in fruits of 20 days after anthesis, and with lower expression levels than 1573bp. Fragment of 795bp was not able to direct GUS expression in any of the tissues bombarded (data not shown). It can be concluded that of the 1573bp, 1201 bp, 898bp Wml1 5'flanking regions include the necessary information directing fruit-specific expression. Deletion from 180bp to 551bp doesn't affect the fruit-specificity of the promoter, but lowered the expression level. There may be some cis-acting elements located in this region, which can enhance external gene expression in later stages of fruit development. Deletion from 854bp and 958bp led to loss of GUS expression. This region includes the necessary information needed for gene expression as well as the regulatory elements for fruit-specific transcription.


Asunto(s)
Citrullus/genética , Frutas/genética , Regiones Promotoras Genéticas/genética , Secuencias Reguladoras de Ácidos Nucleicos/fisiología , Regulación de la Expresión Génica de las Plantas/genética , Secuencias Reguladoras de Ácidos Nucleicos/genética
20.
Shi Yan Sheng Wu Xue Bao ; 36(3): 226-32, 2003 Jun.
Artículo en Zh | MEDLINE | ID: mdl-12966734

RESUMEN

According to its restriction sites, fragments of 1573 bp, 1197 bp, 896 bp and 795 bp were obtained from the 5' promoter region of wml1 and fused with the coding sequence of the GUS gene. Constructs containing these fragments were introduced into tomato plants via Agrobacterium-mediated transformation. Histochemical assay of GUS expression in transgenic tomato plants revealed that fragments of 1573 bp, 1197 bp, 896 bp were able to direct GUS expression in fruits of 15, 30, 45 days after anthesis with the expression level of GUS increasing with fruit development, but not in leaves, stems and roots. While no GUS expression was observed in tomato plants transformed by construct containing fragment of 795 bp. It was determined that the region from 857 bp to 957 bp contains the elements necessary for directing fruit-specific expression.


Asunto(s)
Citrullus/genética , Plantas Modificadas Genéticamente/genética , Regiones Promotoras Genéticas/genética , Solanum lycopersicum/genética , Elementos Transponibles de ADN/genética , Frutas/genética , Frutas/crecimiento & desarrollo , Regulación de la Expresión Génica de las Plantas/genética , Rhizobium/genética , Transcripción Genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA