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1.
J Asthma ; 59(11): 2135-2142, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34752186

RESUMEN

OBJECTIVE: Asthma is a chronic disorder of the airways, in which chemokines coordinate airway inflammation and determine its severity. We aimed to study the chemokine interferonγ-inducible protein 10 kDa (IP10/CXCL10), a member of the CXC receptor 3 (CXCR3) ligand family, at the protein level in the serum of children, to evaluate the association between CXCL10 and exacerbations of childhood asthma. METHODS: Patients experiencing an asthma exacerbation (42 patients) and stable patients (43 patients) were investigated for serum CXCL10 levels. RESULTS: Patients with an asthma exacerbation expressed significantly higher CXCL10 levels in the serum than stable patients (p < 0.001). Additionally, CXCL10 values were elevated in severe asthma compared with moderate and mild disease (p < 0.001). In patients experiencing asthma exacerbations, higher values of CXCL10 were observed in atopic patients compared with non-atopic patients (p = 0.027) and in uncontrolled and partly controlled patients compared with controlled patients (p = 0.046). CONCLUSIONS: CXCL10 is proposed as an inflammatory serum marker for asthma exacerbations and worsening asthma symptoms. The levels of CXCL10 are representative of the clinical severity of asthma.


Asunto(s)
Asma , Quimiocina CXCL10 , Niño , Humanos , Inflamación , Ligandos , Sistema Respiratorio
2.
Luminescence ; 36(4): 964-976, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33590669

RESUMEN

A simple method for the preparation of multifunctional nanocomposite was developed towards the production of water-repellent, electrically conductive, and photoluminescent film onto cotton fibres. The nanocomposite was composed of lanthanide-doped strontium aluminium oxide and silicon rubber dispersed in petroleum ether. The electrically conductive fabric was woven from nickel strips twisted with cotton filaments as core yarns, which were wrapped with pure cotton yarns. The nanoparticles (NPs) of lanthanide-doped strontium aluminium oxide were mixed with environmentally friendly room-temperature vulcanizing silicon rubber (RTV-SR) dissolved in petroleum ether to give the silicon rubber/strontium aluminate nanocomposites. The produced nanocomposites were applied onto electrically conductive cotton/nickel fibres using spray-coating technology. The surface of the cotton/nickel fibres showed different hierarchical morphologies depending on the total content of the silicon rubber. Additionally, the superhydrophobic effect was found to be improved upon increasing the total content of the luminescence pigment NPs. The morphologies of the prepared phosphor NPs were determined using transmission electron microscopy (TEM). The generated transparent luminescence film demonstrated an absorbance peak at 358 nm and an emission peak at 515 nm. Photoluminescence of cotton fibres was monitored with the generation of different colours, including grey, green-yellow, bright white, and turquoise shades as recognized using CIE Laboratory colorimetric parameters. The emission, excitation, lifetime, and decay time spectra of the phosphorescent spray-coated cotton samples were studied. The surface morphologies and chemical compositions of the spray-coated cotton/nickel were investigated using wavelength-dispersive X-ray fluorescence (WD-XRF), scanning electron microscope (SEM), Fourier-transform infrared spectra (FTIR), and energy-dispersive X-ray analyzer (EDAX). The superhydrophobic effects were characterized by measuring static water contact angle. The comfort characteristics of the treated cotton/nickel substrates were assessed by investigating their air permeability and stiffness. The treated cotton/nickel fabrics also displayed an antimicrobial activity. The results displayed water repellence with high electrical conductivity and photoluminescence properties.


Asunto(s)
Fibra de Algodón , Nanocompuestos , Conductividad Eléctrica , Interacciones Hidrofóbicas e Hidrofílicas , Luminiscencia
3.
Clin Rehabil ; 33(11): 1819-1830, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31266351

RESUMEN

OBJECTIVE: To establish the prevalence of unmet need for spasticity management in care home residents in two counties of the United Kingdom. DESIGN: Cross-sectional observational study with a six-month follow-up arm for participants with identified unmet needs. SETTING: 22 care homes in Derbyshire and Nottinghamshire. SUBJECTS: 60 care home residents with upper motor neuron syndrome-related spasticity. INTERVENTIONS: No intervention. When unmet needs around spasticity management were identified, the participant's general practitioner was advised of these in writing. MAIN MEASURES: Resistance to Passive Movement Scale to assess spasticity; recording of (a) the presence of factors which may aggravate spasticity, (b) potential complications of spasticity, (c) spasticity-related needs and (d) current interventions to manage spasticity. Two assessors judged the presence or absence of needs for spasticity management and whether these needs were met by current care. RESULTS: Out of 60 participants, 14 had no spasticity-related needs; 46 had spasticity-related needs; 11 had needs which were being met by current care and 35 participants had spasticity-related needs at baseline which were not being met by their current care. These were most frequently related to the risk of contracture development or problems with skin hygiene or integrity in the upper limb. In total, 6 participants had one or more pressure sores and 35 participants had one or more established joint contractures. A total of 31 participants were available for follow-up. Informing general practitioners of unmet needs resulted in no change to spasticity management in 23/31 cases. CONCLUSION: Care home residents in this study had high levels of unmet need for spasticity management.


Asunto(s)
Necesidades y Demandas de Servicios de Salud , Enfermedad de la Neurona Motora/complicaciones , Espasticidad Muscular/complicaciones , Anciano , Anciano de 80 o más Años , Contractura/etiología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Úlcera por Presión/etiología , Prevalencia , Instituciones Residenciales , Cuidados de la Piel , Reino Unido
4.
Environ Sci Pollut Res Int ; 31(35): 47655-47673, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39003426

RESUMEN

Phytoremediation is an in situ remediation and eco-friendly technique employing accumulator plant species to remove trace elements (TEs) from contaminated sites. Moreover, it has been demonstrated that both natural and synthetic amendments can enhance trace elements (TEs) phytoremediation from polluted soils through bioenergy crops. This work assessed the synergistic impact of two tested biochar (BC) from data palm (B1) and Prosopis (B2) (1.5%/ kg), citric acid (CA, 1.5 mmol/kg) and vermiwash (VW, 20 ml/kg) to enhance the remediation of tested TEs (Mn, Zn, Cd, Pb, Ni, Cu, and Fe) from Mahad AD'Dahab mine-contaminated soil by sorghum (Sorghum bicolor L.). The BC and CA amendments alone and combined with VW significantly augmented the proliferation and survival of sorghum grown in mine-contaminated soil. Considering the individual and combined applications of VW and BC, the influence on plant growth followed this order: K < VW < B2 < B1 < B1 + VW < B2 + VW < CA < CA + VW. Applying tested BC/CA and VW significantly increased chlorophyll compared to unamended soil. The outcomes revealed a substantial elevation in TE absorption in both shoot and root (p ≤ 0.05) with all tested treatments compared to the untreated soil (K). The combined application of CA and VW resulted in the most significant TE uptake of TEs at both the root and the shoot. Furthermore, adding CA or VW as a foliar spray enhanced the bioaccumulation factor (BCF) and translocation factor (TF) of studied metals. The combined addition of CA and foliar spraying of VW was more effective than the sole addition of CA or VW. Such increase reached 20.0%, 15.6%, 19.4%, 14.3%, 14.0%, and 25.6% of TF, and 13.7%, 11.9%, 8.3%, 20.9%, 20.5%,18.7%, and 19.8% of BCE for Cd, Cu, Fe, Mn, Ni, Pb, and Zn, respectively. This study highlights the efficiency of combining CA/BC with VW as a more viable option for remediating mine-contaminated soil than individual amendments. However, future research should prioritize long-term field trials to assess the efficiency of using citric acid and vermiwash for restoring contaminated mining soils.


Asunto(s)
Biodegradación Ambiental , Carbón Orgánico , Ácido Cítrico , Minería , Contaminantes del Suelo , Suelo , Sorghum , Carbón Orgánico/química , Ácido Cítrico/química , Suelo/química , Restauración y Remediación Ambiental/métodos
5.
RSC Adv ; 14(12): 7964-7980, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38454937

RESUMEN

Fifteen new iodoquinazoline derivatives, 5a,b to 18, are reported in this study and their anticancer evaluation as dual inhibitors of EGFRWT and EGFRT790M. The new derivatives were designed according to the target of structural requirements of receptors. Cytotoxicity of our compounds was evaluated against MCF-7, A549, HCT116 and HepG2 cell lines using MTT assay. Compounds 18, 17 and 14b showed the highest anticancer effects with IC50 = 5.25, 6.46, 5.68 and 5.24 µM, 5.55, 6.85, 5.40 and 5.11 µM and 5.86, 7.03, 6.15 and 5.77 µM against HepG2, MCF-7, HCT116 and A549 cell lines, respectively. The eight highly effective compounds 10, 13, 14a, 14b, 15, 16, 17 and 18 were inspected against VERO normal cell lines to evaluate their cytotoxicity. Our conclusion was that compounds 10, 13, 14a, 14b, 15, 16, 17 and 18 possessed low toxicity against VERO normal cells with IC50 increasing from 43.44 to 52.11 µM. All compounds were additionally assessed for their EGFRWT and EGFRT790M inhibitory activities. Additionally, their ability to bind with EGFRWT and EGFR receptors was confirmed by molecular docking. Compound 17 exhibited the same inhibitory activity as erlotinib. Compounds 10, 13, 14b, 16 and 18 excellently inhibited VEGFR-2 activity with IC50 ranging from 0.17 to 0.50 µM. Moreover, compounds 18, 17, 14b and 16 remarkably inhibited EGFRT790M activity with IC50 = 0.25, 0.30, 0.36 and 0.40 µM respectively. As planned, compounds 18, 17 and 14b showed excellent dual EGFRWT/EGFRT790M inhibitory activities. Finally, our compounds 18, 17 and 14b displayed good in silico ADMET calculated profiles.

6.
Environ Sci Pollut Res Int ; 30(15): 43872-43885, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36670224

RESUMEN

Crop plant remediation and detoxification of Zn-contaminated soils may pose a significant threat to food safety and, thus, human health. Therefore, the current study was carried out to assess the ability of six non-food crop plants (NFCP); Zea mays L. cultivar 360 (T360), Z. mays cultivar 123 (T123), Helianthus annuus L., Brassica juncea (L.) Czern., Ricinus communis L., and Simmondsia chinensis (Link) C.K. Schneid to remediate and restore Zn-contaminated soils. The investigated plants tolerate 150 mg/kg of Zn content of the soil, where they had tolerance index (TI) > 1 for all growth criteria, except the root dry weight (DW) of S. chinensis. Z. mays T123 and R. communis were the most susceptible plants, while B. juncea and S. chinensis were moderately tolerant, while H. annuus was the most tolerant to high Zn concentrations in a growing medium. Increasing the soil Zn content led to a significant increase (p < 0.05) in Zn concentration in the various tissues of the six NFCPs. The studied NFCP did not translocate Zn to their grains/seeds; consequently, they can be used safely for Zn-contaminated soils. The Zn content in root and shoot was negatively correlated with the TI of their length and weight, while the translocation factor (TF) of Zn from root to shoot was positively correlated to the TI of the root length and weight. The six studied NFCPs were arranged based on their phytoremediation efficiency as follows: B. juncea (31.86%) > Z. mays T123 (31.14%) > Z. mays T360 (27.59%) > H. annuus (20.85%) > S. chinensis (20.29%) > R. communis (15.3%). All tested NFCPs accumulated significant concentrations of Zn in their roots and shoots, a high Zn uptake potential, and biomass at 150-450 mg/kg of Zn treatments, indicating that these plants are good candidates for the implementation of a new strategy of cultivating NFCP for phytoremediation of Zn-contaminated soils.


Asunto(s)
Contaminantes del Suelo , Zinc , Humanos , Zinc/análisis , Plantas Comestibles , Contaminantes del Suelo/análisis , Raíces de Plantas/química , Biodegradación Ambiental , Suelo
7.
Heliyon ; 9(1): e12988, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36820175

RESUMEN

In arid ecosystems, lack of vegetation and nutrients can negatively impact soil carbon (C) content. In the current study, our goals were to assess soil C stocks to a depth of 50 cm in an arid ecosystem (Wadi Al-Sharaea, Saudi Arabia) and determine their relation to different vegetation cover. To address our research objective, a total of 102 quadrate (randomly selected) were established along the desert wadi. Soil samples were collected to a depth of 50 cm with 5 cm interval, then Soil Bulk Density (SBD, g/cm3), Soil Organic C Content (SOC, g C/kg), and stocks (kg C/m2) were estimated. Both soil mechanical and chemical analyses were conducted for a composite soil sample. Study sites were categorized based on their visual vegetation cover (VC) percentage (%) into three major groups: 1) scarce vegetation cover (VC less than 25%); 2) medium vegetation cover (VC is higher than 25% and less than 75%); and lastly 3) dense vegetation cover (VC is higher than 75%). Soils were characterized by higher sand content (48.2%, both fine and coarse compiled) than silt (36.7 ± 1.64%) or clay (10.1 ± 1.28%). There were significant differences among soil Calcium (Ca) and Potassium (K) content (p < 0.05), while those plant communities with medium vegetation cover showed the highest soil content of Ca and K (1.7 ± 0.24 and 0.2 ± 0.03 meq/l, respectively). Plant communities with dense vegetation cover had the lowest SBD (1.96 ± 0.03 g/cm3) and the highest SOC stocks (14.9 ± 2.1 kg C/m2). Moreover, our data analyses indicated that SBD and SOC content had strong and negative correlation, where soils with dense vegetation cover had the most significant correlation (R2 = 0.95). Our results recommend that soil carbon stocks to a depth of 50 cm based on different vegetation cover of arid ecosystems should be implemented on global soil carbon budget to better elucidate factors controlling SOC content at the regional and global scales.

8.
Environ Sci Pollut Res Int ; 30(8): 20590-20600, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36253577

RESUMEN

The present study aimed to assess the efficiency of the water hyacinth (Eichhornia crassipes (Mart.) Solms) plant for the reduction of nitrogen and phosphorus pollutants from glass industry effluent (GIE) as batch mode phytoremediation experiments. For this, response surface methodology (RSM) and artificial neural networks (ANN) methods were adopted to evidence the optimization and prediction performances of E. crassipes for total Kjeldahl's nitrogen (TKN) and total phosphorus (TP) removal. The control parameters, i.e., GIE concentration (0, 50, and 100%) and plant density (1, 3, and 5 numbers) were used to optimize the best reduction conditions of TKN and TP. A quadratic model of RSM and feed-forward backpropagation algorithm-based logistic model (input layer: 2 neurons, hidden layer: 10 neurons, and output layer: 1 neuron) of ANN showed good fitness results for experimental optimization. Optimization results showed that maximum reduction of TKN (93.86%) and TP (87.43%) was achieved by using 60% of GIE concentration and nearly five plants. However, coefficient of determination (R2) values showed that ANN models (TKN: 0.9980; TP: 0.9899) were superior in terms of prediction performance as compared to RSM (TKN: 0.9888; TP: 0.9868). Therefore, the findings of this study concluded that E. crassipes can be effectively used to remediate nitrogen and phosphorus loads of GIE and minimize environmental hazards caused by its unsafe disposal.


Asunto(s)
Eichhornia , Contaminantes Ambientales , Contaminantes Químicos del Agua , Biodegradación Ambiental , Fósforo , Nitrógeno , Contaminantes Químicos del Agua/análisis , Plantas , Redes Neurales de la Computación
9.
Environ Sci Pollut Res Int ; 28(36): 50217-50229, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33948848

RESUMEN

Food safety has often attracted attention worldwide. Few studies have investigated the heavy metal (HM) pollution and health risk assessment of crops and vegetables. The current work was conducted to evaluate the human risk assessment of HM (Cu, Cd, Cr, Pb, and Zn) in radish, lettuce, tomato, onion, turnip, squash, okra, sunflower, Jews mallow, and garden rocket cultivated in treated wastewater (TWW)-irrigated sites as compared with those cultivated in freshwater (FW)-irrigated sites. Irrigation water, soil, and different plants were collected from 6 farmlands irrigated with TWW and two agricultural sites irrigated with FW (Nile river). Heavy metal transfer factor (HMTF), chronic daily intake of metals (CDIM), health hazard risk (HR), and health hazard index (HI) were estimated. The results showed that the tested HM levels in FW and TWW were below the Food and Agriculture Organization (FAO) and Egyptian standards recommended for irrigation. In soil samples, HM levels were below the permissible limits for both tested sites. The HM in soil and plants grew in TWW-irrigated sites possessed multiple levels higher than those grown in FW-irrigated sites. Among different plants, HM levels in the edible parts of plants grown in TWW-irrigated sites followed in decreasing order: tomato > sunflower >Jew's mallow = turnip = squash > lettuce > okra = radish > onion > garden rocket. The mean CDIM and HR values of plants irrigated using TWW were higher than those irrigated using FW. Furthermore, HR values for all plants grown in polluted and unpolluted sites were < 1 except Cd in plants grown in the TWW-irrigated farmlands. The mean HI for radish, lettuce, tomato, onion, turnip, squash, okra, sunflower, Jews mallow, and garden rocket grown in TWW-irrigated sites were 2.08, 2.39, 1.76, 1.53, 2.08, 1.80, 2.03, 1.91, 1.82, and 1.44 (for adult), and 2.39, 2.75, 2.71, 1.75, 2.38, 2.06, 2.33, 2.69, 2.10, and 1.65 (for children). Plants irrigated with TWW showed a higher HMTF than plants irrigated with FW. Jew's mallow and okra irrigated with TWW had a maximum HMTF. Consequently, different practical measures can be taken to minimize the HM levels in agricultural foodstuffs. These measures include preventing the excessive application of pesticides and fertilizers for crop production and continuous monitoring of different foodstuffs in the market.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Adulto , Bioacumulación , Niño , Egipto , Monitoreo del Ambiente , Agua Dulce , Humanos , Metales Pesados/análisis , Medición de Riesgo , Contaminantes del Suelo/análisis , Aguas Residuales/análisis
10.
J Investig Med ; 66(8): 1102-1108, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29970479

RESUMEN

Children with severe asthma or acute asthma exacerbation may encounter difficulties in performing pulmonary function tests. In this situation, serum biomarkers can play a great role in evaluation of such patients. The aim of this study was to estimate the serum levels of human chitinase-3-like protein 1 (YKL40) and periostin in a group of Egyptian children with asthma during acute asthma exacerbation and in stable asthmatics compared with healthy control, and to correlate these findings with the severity of asthma. This cross-sectional study enrolled 120 childrenwith asthma with different degrees of asthma severity, according to the Global Initiative for Asthma guidelines, along with 60 age-matched and sex-matched healthy control. A complete blood count and an estimation of serum periostin and YKL40 levels were performed for all cases and control. Individual and mean values of periostin and YKL40 were significantly higher during acute asthma exacerbations, p<0.001. A highly significant relation between serum levels of periostin and YKL40 and asthma severity, p value for each was <0.001. Absolute eosinophil count was significantly correlated with the serum periostin levels in stable asthmatic group (p=0.01) only. There was significantly positive correlation (P<0.001) between both markers in stable asthmatic group. Spearman's correlation coefficient shows a statistically significant positive correlation between both markers and patient's age and duration of asthma, p value for each was 0.001. These findings highlight the importance of periostin and YKL40 as serum biomarkers for assessment of asthma severity and acute asthma exacerbations in children with asthma.


Asunto(s)
Asma/sangre , Asma/patología , Moléculas de Adhesión Celular/sangre , Proteína 1 Similar a Quitinasa-3/sangre , Progresión de la Enfermedad , Índice de Severidad de la Enfermedad , Biomarcadores/sangre , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Humanos , Masculino , Fenotipo
11.
J Colloid Interface Sci ; 531: 181-188, 2018 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-30031260

RESUMEN

Quartz substrate supported Praseodymium (Pr) doped strontium molybdate (SrMoO4) thin films with good uniformity and outstanding fluorescent properties are successfully fabricated via a facile polymer-assisted deposition (PAD) method. In combination with the strong chelating effect of water-soluble polymer on metal cations, the free cations without chelating are effectively ruled out but the remaining chelating metal cations are employed for the highly uniform and accurate stoichiometry luminescent SrMoO4: Pr thin films, layer-by-layer mounting on the common quartz substrates. More importantly, the excellent release of stress from polymer during the growth process of epitaxial thin film can effectively overcome the mismatch between thin film and common quartz substrate and then guarantee the quality of thin film. Under the ultraviolet (UV) light excitation, the samples show high luminescence intensity both in visible and near-infrared (NIR) regions peaked at 646 nm and 1037 nm, mainly ascribing to the transitions of 3P0 → 3F2 and 1G4 → 3H4 of Pr3+ ions. The luminescent properties can be tailored by optimizing the number of spin-coated layers and doping concentrations. The maximum emission occurs at 4 mol% of Pr3+ dopant, and it exhibits an impressive high photoluminescence quantum yield (QY) of up to 86.12%. These results evidently demonstrate the present PAD method is a useful prototype for preparing high performance luminescent thin films even on the cheap quartz substrate.

12.
Innate Immun ; 24(3): 171-179, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29635981

RESUMEN

Childhood asthma represents a worldwide problem, involving genetic, immune defense and environmental components. MicroRNAs (miRs) are non-coding, single-stranded RNAs involved in immune regulation. The aim was to evaluate clinical potential of plasma miR-21 and miR-146a involved in T helper differentiation in childhood asthma and non-asthmatic controls. Group 1 consisted of 27 asthmatic children receiving inhaled corticosteroids (ICSs), which was compared to group 2 with 21 healthy control children. All patients were assessed by pulmonary function tests. miR-21 and miR-146a expression levels were determined by real-time quantitative PCR, and IL-13 was measured using ELISA. Group 1 showed significant up-regulation of plasma miR-21 and miR-146a levels with mean values 42.6-fold and 4.7-fold higher than average expression, respectively, in group 2. miR-21 levels positively correlated with IL-13 levels and eosinophil percentage, while miR-146a only correlated to eosinophil percentage. There was a linear association between each of miR-21 and miR-146a expression and FEV1 (forced expiratory volume in the first second), miR-21 and miR-146a are up-regulated in asthmatic children. miR-21 served as a better asthma biomarker. Association between both markers and FEV1 points to their role in determining asthma outcome following ICS treatment. miR-21 and miR-146a play a role in eosinophilic endotypic classification of asthma.


Asunto(s)
Asma/genética , Interleucina-13/genética , MicroARNs/genética , Corticoesteroides/uso terapéutico , Factores de Edad , Antiasmáticos/uso terapéutico , Asma/metabolismo , Asma/fisiopatología , Biomarcadores , Estudios de Casos y Controles , Diferenciación Celular/genética , Niño , Eosinófilos , Femenino , Volumen Espiratorio Forzado , Humanos , Interleucina-13/biosíntesis , Masculino , MicroARNs/biosíntesis , Factores Sexuales , Linfocitos T Colaboradores-Inductores , Células Th2 , Regulación hacia Arriba/efectos de los fármacos
13.
Biochemistry ; 44(17): 6565-72, 2005 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-15850390

RESUMEN

We prepared a series of cryptogein mutants, an elicitor from Phytophthora cryptogea, with altered abilities to bind sterols and fatty acids. The induction of the early events, i.e., synthesis of active oxygen species and pH changes, in suspension tobacco cells by these mutated proteins was proportional to their ability to bind sterols but not fatty acids. Although the cryptogein-sterol complex was suggested to be a form triggering a defense reaction in tobacco, some proteins unable to bind sterols induced the synthesis of active oxygen species and pH changes. The modeling experiments showed that conformational changes after the introduction of bulky residues into the omega loop of cryptogein resemble those induced by sterol binding. These changes may be necessary for the ability to trigger the early events by elicitins. However, the ability to stimulate necrosis in suspension tobacco cells and the expression of defense proteins in tobacco plants were linked neither to the lipid binding capacity nor to the capacity to provoke the early events. On the basis of these experiments and previous results, we propose that elicitins could stimulate two signal pathways. The first one induces necroses and the expression of pathogen-related proteins, includes tyrosine protein kinases and mitogen-activated protein kinases, and depends on the overall structure and charge distribution. The second type of interaction is mediated by phospholipase C and protein kinase C. It triggers the synthesis of active oxygen species and pH changes. This interaction depends on the ability of elicitins to bind sterols.


Asunto(s)
Proteínas Algáceas/síntesis química , Proteínas Algáceas/genética , Ergosterol/análogos & derivados , Mutagénesis Sitio-Dirigida , Nicotiana/microbiología , Phytophthora/genética , Phytophthora/patogenicidad , Proteínas Algáceas/metabolismo , Proteínas Algáceas/toxicidad , Dicroismo Circular , Simulación por Computador , Ergosterol/metabolismo , Ácidos Grasos/metabolismo , Proteínas Fúngicas , Metabolismo de los Lípidos , Micotoxinas/síntesis química , Micotoxinas/genética , Micotoxinas/toxicidad , NADPH Oxidasas/biosíntesis , Fenilanina Amoníaco-Liasa/biosíntesis , Enfermedades de las Plantas/microbiología , Proteínas de Plantas/biosíntesis , Unión Proteica/genética , Proteínas , Relación Estructura-Actividad Cuantitativa , Especies Reactivas de Oxígeno/metabolismo , Proteínas Recombinantes/síntesis química , Proteínas Recombinantes/genética , Proteínas Recombinantes/toxicidad , Nicotiana/citología , Nicotiana/enzimología , Nicotiana/metabolismo
14.
J Biol Chem ; 277(43): 41259-67, 2002 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-12186872

RESUMEN

Angiotensin II (Ang II) and adrenocorticotropic hormone stimulate aldosterone biosynthesis in the zona glomerulosa of the adrenal cortex through induction of the expression of the steroidogenic acute regulatory (StAR) protein, which promotes intramitochondrial cholesterol transfer. To understand the mechanism of this induction of the StAR protein, we have examined the effect of Ang II and forskolin, a mimicker of adrenocorticotropic hormone action, on two transcription factors known to modulate StAR gene expression in opposite ways, DAX-1 and SF-1, in bovine adrenal glomerulosa cells in primary culture. Ang II markedly inhibited DAX-1 protein expression in a time- and concentration-dependent manner (to 38.7 +/- 12.9% of controls at 3 nm after 6 h, p < 0.01), an effect that required de novo protein synthesis and ERK2/1 activation. This effect was associated with a concomitant decrease in DAX-1 mRNA and an increase in mitochondrial StAR protein levels. Similarly, forskolin dramatically repressed DAX-1 protein and mRNA expression (to 19.6 +/- 1.8 and 50.3 +/- 4.7% of controls, respectively, p < 0.01). Neither Ang II nor forskolin affected DAX-1 protein and mRNA stability. The aldosterone response to Ang II was markedly reduced (to 59 +/- 4% of controls, p < 0.01) in transiently transfected cells overexpressing DAX-1. Whereas Ang II was without effect on SF-1 expression, forskolin significantly increased SF-1 protein and mRNA levels in a cycloheximide-sensitive manner (to 167.4 +/- 16.6 and 173.1 +/- 25.1% of controls after 6 h, respectively, p < 0.01). These results demonstrate that the balance between repressor and inducer function of DAX-1 and SF-1 are of critical importance in the regulation of adrenal aldosterone biosynthesis.


Asunto(s)
Aldosterona/biosíntesis , Proteínas de Unión al ADN/genética , Proteínas de Unión al ARN/genética , Receptores de Ácido Retinoico/genética , Proteínas Represoras , Factores de Transcripción/genética , Zona Glomerular/metabolismo , Angiotensina II/farmacología , Animales , Secuencia de Bases , Bovinos , Células Cultivadas , Colforsina/farmacología , Receptor Nuclear Huérfano DAX-1 , Cartilla de ADN , Activación Enzimática , Regulación de la Expresión Génica/efectos de los fármacos , Cinética , Proteína Quinasa 1 Activada por Mitógenos/metabolismo , Proteína Quinasa 3 Activada por Mitógenos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Datos de Secuencia Molecular , ARN Mensajero/genética , ARN Mensajero/metabolismo , Zona Glomerular/citología , Zona Glomerular/enzimología
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