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1.
Biotechnol Appl Biochem ; 70(3): 1109-1120, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36480009

RESUMEN

To verify the inhibitory mechanism of ß-catenin-designed peptides in colorectal cancer(CRC) tumors, the following experiments were performed. In vitro colony formation, Transwell assays, and flow cytometry were performed to assess the biological effects of designed peptides (F18KD, F20A4-7k, F20A4-10k, and F20A3-9k + F20A4-10k + F20A5-9k) in HT-29 cells. In vivo xenograft experiments were performed and treated with peptides. Next, tumors were subjected to Hematoxylin and eosin staining (HE), immunohistochemical, and terminal deoxynucleotidyl transferase dUTP nick end labeling staining assays to evaluate the inhibitory effect of peptides on tumors. ß-Catenin levels were quantified via western blotting (WB) and quantitative real-time polymerase chain reaction, and ß-catenin was located using confocal laser scanning microscopy. T-cell factor-4 (TCF-4), C-myc, and CCND1 levels were quantified via WB. Results were obtained as following. First, the peptides reduced viability, migration, and invasion; promoted apoptosis; and stabilized the S phase of HT-29 cells. Second, peptides suppressed tumor growth and downregulated the expression of CD34, vascular endothelial growth factor, and ß-catenin in tumors. Furthermore, we found that peptides downregulated ß-catenin expression in both the cytoplasm and nucleus; TCF-4, C-myc, and CCND1 expression was also downregulated. Notably, ß-catenin-targeting peptides had a better inhibitory effect on CRC than non-ß-catenin-target peptides, and a combination of peptides exerted a more potent inhibitory effect on CRC than single peptides. It suggested that ß-Catenin-targeting peptides promote apoptosis in CRC tumors by inhibiting activation of the Wnt/ß-catenin pathway.


Asunto(s)
Neoplasias Colorrectales , Factor A de Crecimiento Endotelial Vascular , Humanos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Vía de Señalización Wnt , Apoptosis , Péptidos/farmacología , Péptidos/metabolismo , Proliferación Celular , Línea Celular Tumoral , Movimiento Celular , Regulación Neoplásica de la Expresión Génica
2.
Artículo en Inglés | MEDLINE | ID: mdl-37128809

RESUMEN

Accurately assessing the health risks of human exposure to heavy metals via water is of great importance for performing targeted health risk prevention measures. To better understand the concentration characteristics and potential harm to human health of cadmium, chromium, lead and arsenic in the main drinking water-type reservoirs of Changzhou city, we collected samples from the Haidi Reservoir, Dongjin Reservoir, Xinfushan Reservoir, Maodong Reservoir and Xiangyang Reservoir of Changzhou in the summer of 2019. The results showed that the daily average comprehensive exposure level of metals was much lower than the provisional tolerated daily intake (PTDI), i.e., Cd: 1 µg kg-1 d-1; Cr: 3 µg kg-1 d-1; Pb: 3.57 µg kg-1 d-1; and As: 2.14 µg kg-1 d-1. The comprehensive non-carcinogenic risk levels of four metals under water-drinking exposure and water-skin exposure routes ranged from 4.68E - 3 to 1.69E - 1, and the carcinogenic risk ranged from 2.09E - 5 to 7.30E - 5, which were all at acceptable risk levels. Although lead and chromium were present at acceptable health risk levels, they still represented the main pollutants of potential health risk in the local water environment from a non-carcinogenic or carcinogenic perspective, and they should be listed as the primary targets for water environmental risk management.


Asunto(s)
Arsénico , Agua Potable , Metales Pesados , Humanos , Arsénico/análisis , Cadmio/análisis , Cromo , Plomo , Monitoreo del Ambiente , Metales Pesados/análisis , Agua Potable/análisis , China , Medición de Riesgo
3.
Zhongguo Zhong Yao Za Zhi ; 46(11): 2753-2759, 2021 Jun.
Artículo en Zh | MEDLINE | ID: mdl-34296572

RESUMEN

Through the investigation of a large number of both domestic and overseas literatures and related quality standards, chemical compositions, quality evaluation system and quality control methods of Succus Bambusae were systematic summarized in this study. There were abundant chemical constituents in Succus Bambusae, mainly including volatile ingredients, amino acids, flavonoids, trace elements and vitamins, with high medicinal and edible value. The quality control methods involved traditional morphological identification, spectroscopy, chromatography and other techniques. However, the current quality standards of Succus Bambusae are relatively low, lacking safety indicators, and cannot effectively ensure its quality, seriously affecting the safety and effectiveness of its clinical use. Therefore, it is particularly important to establish a set of highly sensitive and specific quality evaluation system for Succus Bambusae. In this paper, the current research status of the chemical compositions and quality standards of Succus Bambusae were reviewed, with the purpose of providing a basis for further improvement of its quality evaluation system.


Asunto(s)
Medicamentos Herbarios Chinos , Flavonoides , Control de Calidad
4.
Environ Sci Technol ; 45(2): 744-50, 2011 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-21158391

RESUMEN

Fenton and photoassisted Fenton degradation of ordinary hydrophobic cross-linked polystyrene microspheres and sulfonated polystyrene beads (DOWEX 50WX8) have been attempted. While the Fenton process was not able to degrade these polystyrene materials, photoassisted Fenton reaction (mediated by broad-band UV irradiation from a 250 W Hg(Xe) light source) was found to be efficient in mineralizing cross-linked sulfonated polystyrene materials. The optimal loadings of the Fe(III) catalyst and the H(2)O(2) oxidant for such a photoassisted Fenton degradation were found to be 42 µmol-Fe(III) and 14.1 mmol-H(2)O(2) per gram of the sulfonated polystyrene material. The initial pH for the degradation was set at pH 2.0. This photoassisted Fenton degradation process was also able to mineralize commonly encountered polystyrene wastes. After a simple sulfonation pretreatment, a mineralization efficiency of >99% (by net polymer weight) was achieved within 250 min. The mechanism of this advanced oxidative degradation process was investigated. Sulfonate groups introduced to the surface of the treated polystyrene polymer chains were capable of rapidly binding the cationic Fe(III) catalyst, probably via a cation-exchange mechanism. Such a sorption of the photoassisted Fenton catalyst was crucial to the heterogeneous degradation process.


Asunto(s)
Contaminantes Ambientales/química , Procesos Fotoquímicos , Poliestirenos/química , Eliminación de Residuos/métodos , Restauración y Remediación Ambiental/métodos , Peróxido de Hidrógeno/química , Interacciones Hidrofóbicas e Hidrofílicas , Hierro/química , Microesferas , Oxidantes Fotoquímicos/química , Propiedades de Superficie , Rayos Ultravioleta , Residuos/análisis
5.
J Colloid Interface Sci ; 321(1): 96-102, 2008 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-18261741

RESUMEN

The structure and composition evolution of polyvinyl alcohol (PVA) fibers during the fabrication of activated carbon fibers (ACF) by a newly developed method were systematically elucidated. The pore structure of the fibers was significantly influenced by the carbonization and activation conditions. The elemental composition and chemical structure evolution of the fibers during the heat treatment processes were evaluated by elemental analysis, Fourier transform infrared spectrophotometry (FTIR), and X-ray photoelectron spectroscopy (XPS). Crystal structure evolution of the fibers during the heat treatment processes was elucidated by X-ray diffraction (XRD) analysis. Based on these understandings, the process conditions were optimized using an L(9)(3)(4) orthogonal array design matrix. Appropriate process parameters for the fabrication of PVA-ACFs were established as carbonizing the dehydrated fiber at 300 degrees C for 60 min, and then lifting the temperature to 900 degrees C with a heating speed of 10 degrees C/min in an inert atmosphere, thereafter keeping the fiber at 900 degrees C for 60 min in an oxidizing atmosphere.

6.
J Colloid Interface Sci ; 313(1): 80-5, 2007 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-17509602

RESUMEN

Static-air-activated carbon fibers (ACFs) with lotus-root-like axially porous structure were used to adsorb 2,4-dichlorophenol (2,4-DCP) from aqueous solution. The adsorption isotherm was evaluated in the pH range 3.0-11.0. Results indicated that both Langmuir and Redlich-Peterson adsorption isotherms were appropriate for describing the adsorption characteristics of 2,4-DCP at various pH values and that lower pH values were favorable for adsorption. The adsorption of 2,4-DCP was controlled by the synergetic effects of pi-pi interaction and electrostatic attraction, and the former was dominant. Breakthrough curve results showed that the 2,4-DCP removal efficiency increased with an increase in the empty-bed contact time (EBCT). An EBCT of 0.660 min was sufficient for the adsorption of 2,4-DCP onto ACF, indicating a high adsorption rate. Desorption experiment results revealed that the ACF saturated with 2,4-DCP could be regenerated effectively by a 0.001 M NaOH solution.

7.
J Hazard Mater ; 144(1-2): 200-7, 2007 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-17118548

RESUMEN

In this study experiments were conducted to investigate the adsorption of 2,4-dichlorophenol (2,4-DCP) by activated carbon fiber (ACF) activated by static air. With the results of batch experiments at various temperatures, the adsorption isotherms, kinetics and thermodynamics of this adsorption process were evaluated. Four adsorption isotherm models, Langmuir, Freundlich, Redlich-Peterson and Toth equations, were used to fit the experimental data and the results reveal that the adsorption isotherm models fitted the data in the order of: Langmuir>Redlich-Peterson>Toth>Freundlich isotherms. A pseudo second-order adsorption model was better to describe the adsorption data than the pseudo first-order model and the Bangham model at the temperatures tested. The activation energy was calculated to be 40.90 kJ/mol, while the thermodynamic parameters DeltaH and DeltaS were estimated to be -5.82 kJ/mol and 0.07 kJ/(molK), respectively.


Asunto(s)
Carbono/química , Clorofenoles/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Fibra de Carbono , Cinética , Alcohol Polivinílico/química , Soluciones , Termodinámica
8.
J Neurosurg ; 126(1): 45-51, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27015404

RESUMEN

OBJECTIVE Large vertebrobasilar fusiform aneurysms (VFAs) represent a small subset of intracranial aneurysms and are often among the most difficult to treat. Current surgical and endovascular techniques fail to achieve a complete or acceptable result because of complications, including late-onset basilar artery thrombosis and perforator infarction. The parallel-stent placement technique was established in the authors' department, and this study reports the application of this technique in the treatment of unruptured VFAs. METHODS Eight patients with 8 unruptured VFAs who underwent parallel stent placement between April 2011 and August 2012 were included. The diameters of the VFAs ranged from 7.9 to 14.0 mm, and the lengths from 27.5 to 54.4 mm. Of the 8 patients with unruptured VFAs, 3 received double or triple parallel stents and 5 patients received a series-connected stent with another 1 or 2 stents deployed parallel to them. Outcomes for these patients were tabulated, based on the modified Rankin Scale (mRS) score and angiographic results. RESULTS All of the 25 stents were successfully placed without any treatment-related complications. During follow-up, 5 patients had decreased mRS scores, 2 were unchanged, and 1 was increased for subarachnoid hemorrhage. Immediate and follow-up clinical outcome was completely or partially recovered in most patients. Follow-up angiograms revealed 2 aneurysms were reduced in size and 6 were unchanged after stent placement. No in-stent stenosis, occlusion of the posterior inferior cerebellar artery, or perforators jailed by the stent occurred in any of the aneurysms. CONCLUSIONS These results provide encouraging support for the parallel-stent placement technique, which can be envisaged as an alternative strategy against unruptured VFAs. However, testing in more patients is needed.


Asunto(s)
Arteria Basilar/cirugía , Aneurisma Intracraneal/cirugía , Stents , Arteria Vertebral/cirugía , Adulto , Anciano , Arteria Basilar/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Resultado del Tratamiento , Arteria Vertebral/diagnóstico por imagen
9.
Environ Pollut ; 219: 837-845, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27521292

RESUMEN

Heavy metal pollution is a global issue severely constraining aquaculture practices, not only deteriorating the aquatic environment but also threatening the aquaculture production. One promising solution is adopting aquaponics systems where a synergy can be established between aquaculture and aquatic plants for metal sorption, but the interactions of multiple metals in such aquatic plants are poorly understood. In this study, we investigated the absorption behaviors of Cu(II) and Cd(II) in water by water hyacinth roots in both single- and binary-metal systems. Cu(II) and Cd(II) were individually removed by water hyacinth roots at high efficiency, accompanied with release of protons and cations such as Ca2+ and Mg2+. However, in a binary-metal arrangement, the Cd(II) sorption was significantly inhibited by Cu(II), and the higher sorption affinity of Cu(II) accounted for its competitive sorption advantage. Ionic exchange was identified as a predominant mechanism of the metal sorption by water hyacinth roots, and the amine and oxygen-containing groups are the main binding sites accounting for metal sorption via chelation or coordination. This study highlights the interactive impacts of different metals during their sorption by water hyacinth roots and elucidates the underlying mechanism of metal competitive sorption, which may provide useful implications for optimization of phytoremediation system and development of more sustainable aquaculture industry.


Asunto(s)
Eichhornia/metabolismo , Metales Pesados/metabolismo , Raíces de Plantas/metabolismo , Contaminantes Químicos del Agua/metabolismo , Biodegradación Ambiental , Cadmio/metabolismo , Cobre/metabolismo , Intercambio Iónico , Agua/química
10.
Ann N Y Acad Sci ; 1063: 420-4, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16481552

RESUMEN

Historically, ehrlichioses were tick-borne diseases of veterinary medical importance and are now important emerging infectious diseases in humans. p28s are encoded by multigene families with ORFs tandemly arranged with intergenic spaces of variable lengths. We reported initial sequencing of the Ehrlichia muris p28 locus. A model of persistent infection was described and provided tools for study of persistent ehrlichial infection. We completed the sequence of the E. muris p28 locus and examined mRNA expression.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/biosíntesis , Proteínas de la Membrana Bacteriana Externa/genética , Ehrlichia/genética , Ehrlichiosis/microbiología , Animales , Enfermedad Crónica , Modelos Animales de Enfermedad , Regulación Bacteriana de la Expresión Génica , Ratones , Datos de Secuencia Molecular , Análisis de Secuencia de ADN
11.
Neural Netw ; 63: 87-93, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25514097

RESUMEN

The generalization ability of ELM can be improved by fusing a number of individual ELMs. This paper proposes a new scheme of fusing ELMs based on upper integrals, which differs from all the existing fuzzy integral models of classifier fusion. The new scheme uses the upper integral to reasonably assign tested samples to different ELMs for maximizing the classification efficiency. By solving an optimization problem of upper integrals, we obtain the proportions of assigning samples to different ELMs and their combinations. The definition of upper integral guarantees such a conclusion that the classification accuracy of the fused ELM is not less than that of any individual ELM theoretically. Numerical simulations demonstrate that most existing fusion methodologies such as Bagging and Boosting can be improved by our upper integral model.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Modelos Teóricos
12.
Microbes Infect ; 4(6): 625-33, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12048032

RESUMEN

Investigation of the biology, pathology and immunology of rickettsial diseases offers new insights useful not only for the field of rickettsiology, but more importantly for the understanding of general principles of host-intracellular parasite relationships and, in particular, the immune interaction between endothelial cells and immune cells in the context of infection.


Asunto(s)
Infecciones por Rickettsia/inmunología , Rickettsia/inmunología , Vacunas contra Rickettsia/inmunología , Animales , Formación de Anticuerpos , Endotelio/inmunología , Humanos , Inmunidad Celular , Ratones , Rickettsia/metabolismo , Infecciones por Rickettsia/patología , Infecciones por Rickettsia/prevención & control
13.
FEMS Microbiol Lett ; 207(2): 111-20, 2002 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-11958927

RESUMEN

The interaction between intracellular pathogens and the mammalian host follows different pathways that reflect evolved survival mechanisms of both the pathogen and the host to assure each one's own survival. From the host's perspective, different immune mechanisms predominate at different stages of infection. Both phagocytic and non-phagocytic target cells participate in microbial uptake and, in some cases, intracellular destruction. In addition, the development of specific immunity ensures sustained activation of intracellular microbicidal mechanisms in the target cells, and induction of apoptotic or lytic target cell death by cytotoxic T lymphocytes. From the pathogen's perspective, different evasion strategies are employed to counteract host defenses. Understanding microbial survival strategies and the immune mechanisms that result in killing of intracellular pathogens will deepen our insight into the pathogenesis of infection that could be applied towards the development of effective vaccination and immunotherapy.


Asunto(s)
Enfermedades Transmisibles/inmunología , Células Eucariotas/microbiología , Animales , Enfermedades Transmisibles/microbiología , Enfermedades Transmisibles/parasitología , Citocinas/inmunología , Humanos , Inmunidad Celular , Macrófagos/inmunología , Fagocitosis/inmunología , Linfocitos T Citotóxicos/inmunología
14.
Trans Am Clin Climatol Assoc ; 115: 375-82; discussion 382-4, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-17060980

RESUMEN

Ehrlichia chaffeensis are small, obligately intracellular, endosomal bacteria with tropism for macrophages. Persistent infection in reservoir white-tailed deer is transmitted by lone star ticks. Flu-like illness can progress to severe multisystem disease with toxic shock-like syndrome, meningitis, or ARDS. The case-fatality rate is 2.7%. Leukopenia and thrombocytopenia are diagnostically useful. Granulomas are associated with control of the infection. Ehrlichial proteins and glycoproteins have been sequenced and expressed for diagnostic serology and vaccine development. Mouse models (mild disease and persistent infection with E. muris and fatal monocytotropic ehrlichiosis with a Japanese tick isolate) revealed that CD4 and CD8 T type 1 lymphocyte responses, IFN-gamma, TNF-alpha, and antibodies play roles in protective immunity, while a weak CD4 T-helper response, overproduction of TNF-alpha, and very high IL-10 are associated with toxic shock-like mortality. Protection against fatal ehrlichiosis was achieved by prior infection with low virulence E. muris. Acute clinical diagnosis is difficult except by PCR. Response to doxycycline is dramatic.


Asunto(s)
Ehrlichia chaffeensis/patogenicidad , Ehrlichiosis/etiología , Animales , Antibacterianos/uso terapéutico , Modelos Animales de Enfermedad , Reservorios de Enfermedades/virología , Doxiciclina/uso terapéutico , Ehrlichiosis/diagnóstico , Ehrlichiosis/tratamiento farmacológico , Ehrlichiosis/epidemiología , Humanos , Ratones , América del Norte/epidemiología
15.
IEEE Trans Cybern ; 44(5): 620-35, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23782843

RESUMEN

Fusing a number of classifiers can generally improve the performance of individual classifiers, and the fuzzy integral, which can clearly express the interaction among the individual classifiers, has been acknowledged as an effective tool of fusion. In order to make the best use of the individual classifiers and their combinations, we propose in this paper a new scheme of classifier fusion based on upper integrals, which differs from all the existing models. Instead of being a fusion operator, the upper integral is used to reasonably arrange the finite resources, and thus to maximize the classification efficiency. By solving an optimization problem of upper integrals, we obtain a scheme for assigning proportions of examples to different individual classifiers and their combinations. According to these proportions, new examples could be classified by different individual classifiers and their combinations, and the combination of classifiers that specific examples should be submitted to depends on their performance. The definition of upper integral guarantees such a conclusion that the classification efficiency of the fused classifier is not less than that of any individual classifier theoretically. Furthermore, numerical simulations demonstrate that most existing fusion methodologies, such as bagging and boosting, can be improved by our upper integral model.

16.
Mar Pollut Bull ; 64(7): 1435-44, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22608946

RESUMEN

The pharmaceutical residues in waste water from the largest sewage treatment plant (STP) in Northern Taiwan and in seawater around the effluent discharged area were determined. An environmental risk assessment for the marine environment was conducted based on the environment risk quotient (ERQ). The concentrations of the analyzed compounds in STP influent and effluent were generally higher than those found in coastal seawater. Relatively higher values were found at the estuarine mouth and the discharged area, suggesting that the STP effluent is a point source. The removal efficiency and half life of the analyzed compounds were 6.3-46.8% and 3-18 days, respectively. The ERQ value theoretical calculation was generally greater than 1. However, when the measured concentrations replaced the predicated concentrations, the ERQ values were considerably lower than 1. Therefore, our results call for a re-evaluation of the risks posed by pharmaceuticals to coastal marine ecosystems in Northern Taiwan.


Asunto(s)
Monitoreo del Ambiente , Preparaciones Farmacéuticas/análisis , Agua de Mar/química , Eliminación de Residuos Líquidos/estadística & datos numéricos , Contaminantes Químicos del Agua/análisis , Medición de Riesgo , Aguas del Alcantarillado/análisis , Taiwán , Contaminación Química del Agua/estadística & datos numéricos
17.
Mar Environ Res ; 68(4): 178-87, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19586658

RESUMEN

The distributions, contamination status and annual sedimentation flux of trace metals in surface sediments of the East China Sea (ECS) were studied. Higher concentrations of the studied metals were generally found in the inner shelf and the concentrations decreased seaward. The sequences of the enrichment factor (EF) of the studied metals are Cu>Mn>Ni>Zn>Pb>Fe. The values of EF suggest that the metals contamination in the middle and outer shelves of the ECS is still minor. The annual sedimentation fluxes of trace metals in the ECS were: Fe, 3.48 x 10(7)t/y; Mn, 9.07 x 10(5)t/y; Zn, 1.08 x 10(5)t/y; Ni, 4.48 x 10(4)t/y; Pb, 4.32 x 10(4)t/y and Cu, 3.1 x 10(4)t/y, respectively. Approximately 55-70% and 10-17% of the sedimentation fluxes of trace metals were deposited in the inner shelf and the Changjiang estuarine zone.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/química , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Atmosféricos/análisis , Atmósfera/análisis , China , Océanos y Mares
18.
J Hazard Mater ; 171(1-3): 780-5, 2009 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-19596517

RESUMEN

Water hyacinth roots were employed as a biosorbent to remove Cu(II) in aqueous media. Nitrogen adsorption/desorption analysis revealed that the biosorbent was mesoporous with a relatively small surface area. Equilibrium biosorption isotherms showed that the water hyacinth roots possessed a high affinity and sorption capacity for Cu(II) with a monolayer sorption capacity of 22.7 mg g(-1) at initial pH 5.5. Kinetics study at different temperatures revealed that the sorption was a rapid and endothermic process. The activation energy for Cu(II) sorption was estimated to be 30.8 kJ mol(-1), which is typical of activated chemisorption processes. The sorption mechanism was investigated by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, effect of pH and calcium release. These analyses suggested that the biosorption mainly involved the ion exchange of Cu(II) with cations and complex formation with functional groups on the surface of the roots. All the results showed that water hyacinth roots are an alternative low-cost biosorbent for the removal of Cu(II) from aqueous media.


Asunto(s)
Cobre/química , Raíces de Plantas/metabolismo , Purificación del Agua/métodos , Agua/química , Adsorción , Calcio/química , Cationes , Eichhornia , Restauración y Remediación Ambiental , Concentración de Iones de Hidrógeno , Cinética , Nitrógeno/química , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Contaminantes Químicos del Agua/química
19.
Ying Yong Sheng Tai Xue Bao ; 19(7): 1585-90, 2008 Jul.
Artículo en Zh | MEDLINE | ID: mdl-18839923

RESUMEN

An incubation test was conducted with mollisol applied with recommended amount of acetochlor under the conditions of sterilization, microbial inhibitor addition, and non-sterilization. During incubation, the residual amount of acetochlor and the dynamics of soil phospholipid fatty acids (PLFAs) were determined to study the relative contribution of soil microbes on the degradation of applied acetochlor, and the effects of acetochlor on the soil microbial community structure. The results showed that acetochlor was easy to be degraded by soil microbes, and bacteria contributed more than fungi. After applying acetochlor, the contents of various PLFAs changed evidently, and the soil microbial biomass indicated by C14:0, C16:0 and C18:0 was decreased. The bacterial PLFAs decreased significantly at the beginning of the incubation, but had less difference with CK (no acetochlor application) later, suggesting that bacterial activity was restored along with the degradation of acetochlor. The content of fungal PLFAs in the soil samples applied with acetochlor was lower than that of CK, implying that the inhibition of the herbicide to fungi was chronic and irreversible.


Asunto(s)
Ácidos Grasos/química , Fosfolípidos/química , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Toluidinas/metabolismo , Biodegradación Ambiental , Herbicidas/química , Herbicidas/metabolismo , Contaminantes del Suelo/química , Toluidinas/química
20.
J Infect Dis ; 196(4): 629-38, 2007 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-17624851

RESUMEN

The role played by dendritic cells (DCs), initiators and orchestrators of the immune response, remains unclear in rickettsial infections. To investigate their importance in rickettsioses, we analyzed the responses of murine bone marrow-derived DCs (BMDCs) after rickettsial stimulation in vitro and their protective role in vivo. Rickettsia conorii stimulation of BMDCs caused significant maturation and production of proinflammatory cytokines. Transfer of rickettsiae-stimulated DCs protected mice from lethal rickettsial challenge by limiting rickettsial proliferation in vivo, whereas partial protection was observed in mice receiving lipopolysaccharide (LPS)-stimulated DCs. Immunity to R. conorii after transfer of DCs was associated with up-regulation of CD40, CD80, CD86, and major histocompatibility complex class II; with production of IL-2, IL-12, and IL-23; and with production of antigen-specific interferon- gamma in T cells. Taken together, our data suggest that a vigorous proinflammatory response in DCs is associated with protective immunity to rickettsiae and that generation of antigen-specific immunity is crucial to complete protection.


Asunto(s)
Fiebre Botonosa/inmunología , Fiebre Botonosa/prevención & control , Células Dendríticas/inmunología , Rickettsia conorii , Animales , Antígeno B7-1/metabolismo , Antígeno B7-2/metabolismo , Médula Ósea/inmunología , Antígenos CD40/metabolismo , Células Cultivadas , Técnicas de Cocultivo , Células Dendríticas/metabolismo , Células Dendríticas/trasplante , Antígenos de Histocompatibilidad Clase II/metabolismo , Interferón gamma/biosíntesis , Interferón gamma/inmunología , Interleucinas/biosíntesis , Masculino , Ratones , Ratones Endogámicos C3H , Especificidad de la Especie , Linfocitos T/inmunología , Linfocitos T/metabolismo , Regulación hacia Arriba
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