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1.
J Chin Med Assoc ; 84(8): 791-794, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34074932

RESUMEN

BACKGROUND: Post-dural puncture headache (PDPH) is the most common complication of lumbar puncture. Patients who received lumbar puncture were previously suggested to remain in bed for a certain time to prevent PDPH; however, this concept was challenged by recent studies. We aimed to investigate whether ambulation instead of resting supine following lumbar puncture could increase the risk of PDPH. METHODS: The study used a prospective cohort design, applying convenience sampling among patients who received diagnostic lumbar puncture between January and September 2018 in the neurology ward of a tertiary medical center. The patients who fulfilled the inclusion criteria were informed that the current practice suggests lying supine for 6 to 8 hours after lumbar puncture, but they were allowed to either follow the suggestion or ambulate by their wills. The timing of bed rest was recorded, in addition to other possible risk factors of PDPH. The study endpoint is the presence or absence of PDPH within 48 hours of lumbar puncture. RESULTS: A total of 137 patients who received lumbar puncture were enrolled, including 103 with bed rest following lumbar puncture and 34 without. There was no difference in demographics between the two groups. PDPH was found in 21 patients, with a total follow-up period of 5959 person-hours and an incidence density of 0.35%. There was no significant difference between the incidence of PDPH between the two groups (non-bed rest group 5.9% vs bed rest group 18.4%; p = 0.078), nor was incidence density (non-bed rest group 0.13% vs bed rest group 0.43%, p = 0.113). The results remained the same after adjusting for age. CONCLUSION: Bed rest following lumbar puncture does not prevent PDPH, and even leads to a marginally increased risk of PDPH. Amendment to the current practice guideline post-lumbar puncture care might be needed to improve patient care.


Asunto(s)
Reposo en Cama , Cefalea Pospunción de la Duramadre/etiología , Punción Espinal/efectos adversos , Anciano , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Cefalea Pospunción de la Duramadre/epidemiología , Estudios Prospectivos
2.
Sci Rep ; 9(1): 15884, 2019 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-31685928

RESUMEN

The fungus Parastagonospora nodorum infects wheat through the use of necrotrophic effector (NE) proteins that cause host-specific tissue necrosis. The Zn2Cys6 transcription factor PnPf2 positively regulates NE gene expression and is required for virulence on wheat. Little is known about other downstream targets of PnPf2. We compared the transcriptomes of the P. nodorum wildtype and a strain deleted in PnPf2 (pf2-69) during in vitro growth and host infection to further elucidate targets of PnPf2 signalling. Gene ontology enrichment analysis of the differentially expressed (DE) genes revealed that genes associated with plant cell wall degradation and proteolysis were enriched in down-regulated DE gene sets in pf2-69 compared to SN15. In contrast, genes associated with redox control, nutrient and ion transport were up-regulated in the mutant. Further analysis of the DE gene set revealed that PnPf2 positively regulates twelve genes that encode effector-like proteins. Two of these genes encode proteins with homology to previously characterised effectors in other fungal phytopathogens. In addition to modulating effector gene expression, PnPf2 may play a broader role in the establishment of a necrotrophic lifestyle by orchestrating the expression of genes associated with plant cell wall degradation and nutrient assimilation.


Asunto(s)
Ascomicetos/metabolismo , Proteínas Fúngicas/metabolismo , Factores de Transcripción/metabolismo , Triticum/metabolismo , Secuencias de Aminoácidos , Ascomicetos/patogenicidad , Pared Celular/metabolismo , Regulación hacia Abajo , Proteínas Fúngicas/genética , Regulación de la Expresión Génica de las Plantas , Interacciones Huésped-Patógeno/genética , Enfermedades de las Plantas/microbiología , Análisis de Componente Principal , Regiones Promotoras Genéticas , Factores de Transcripción/genética , Triticum/microbiología , Regulación hacia Arriba , Virulencia/genética
3.
Sci Rep ; 8(1): 11851, 2018 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-30087396

RESUMEN

The ACT domain (aspartate kinase, chorismate mutase and TyrA), an allosteric effector binding domain, is commonly found in amino acid metabolic enzymes. In addition to ACT domain-containing enzymes, plants have a novel family of ACT domain repeat (ACR) proteins, which do not contain any recognizable catalytic domain. Arabidopsis has 12 ACR proteins, whose functions are largely unknown. To study the functions of Arabidopsis ACR11, we have characterized two independent T-DNA insertion mutants, acr11-2 and acr11-3. RNA gel-blot analysis revealed that the expression of wild-type ACR11 transcripts was not detectable in the acr11 mutants. Interestingly, a lesion-mimic phenotype occurs in some rosette leaves of the acr11 mutants. In addition, high levels of reactive oxygen species (ROS), salicylic acid (SA), and callose accumulate in the mutant leaves when grown under normal conditions. The expression of several SA marker genes and the key SA biosynthetic gene ISOCHORISMATE SYNTHASE1 is up-regulated in the acr11 mutants. Furthermore, the acr11 mutants are more resistant to the infection of bacterial pathogen Pseudomonas syringae pathovar tomato DC3000. These results suggest that ACR11 may be directly or indirectly involved in the regulation of ROS and SA accumulation, which in turn modulates SA-associated defense responses and disease resistance in Arabidopsis.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Enfermedades de las Plantas/genética , ARN Nucleotidiltransferasas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Ácido Salicílico/metabolismo , Arabidopsis/microbiología , Proteínas de Arabidopsis/genética , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Interacciones Huésped-Patógeno , Transferasas Intramoleculares/genética , Transferasas Intramoleculares/metabolismo , Mutación , Oxidación-Reducción , Enfermedades de las Plantas/microbiología , Hojas de la Planta/genética , Hojas de la Planta/microbiología , Plantas Modificadas Genéticamente , Pseudomonas syringae/fisiología , ARN Nucleotidiltransferasas/genética
4.
Mol Microbiol ; 2018 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-29722915

RESUMEN

To investigate effector gene regulation in the wheat pathogenic fungus Parastagonospora nodorum, the promoter and expression of Tox3 was characterised through a series of complementary approaches. Promoter deletion and DNase I footprinting experiments identified a 25 bp region in the Tox3 promoter as being required for transcription. Subsequent yeast one-hybrid analysis using the DNA sequence as bait identified that interacting partner as the C2H2 zinc finger transcription factor PnCon7, a putative master regulator of pathogenesis. Silencing of PnCon7 resulted in the down-regulation of Tox3 demonstrating that the transcription factor has a positive regulatory role on gene expression. Analysis of Tox3 expression in the PnCon7 silenced strains revealed a strong correlation with PnCon7 transcript levels, supportive of a direct regulatory role. Subsequent pathogenicity assays using PnCon7-silenced isolates revealed that the transcription factor was required for Tox3-mediated disease. The expression of two other necrotrophic effectors (ToxA and Tox1) was also affected but in a non-dose dependent manner suggesting that the regulatory role of PnCon7 on these genes was indirect. Collectively, these data have advanced our fundamental understanding of the Con7 master regulator of pathogenesis by demonstrating its positive regulatory role on the Tox3 effector in P. nodorum through direct interaction.

5.
Sci Rep ; 6: 32324, 2016 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-27578199

RESUMEN

Organic materials are used in novel optoelectronic devices because of the ease and high compatibility of their fabrication processes. Here, we demonstrate a low-driving-voltage cathodic-controlled organic upconverter with a mapping application that converts near-infrared images to produce images of visible blood vessels. The proposed upconverter has a multilayer structure consisting of a photosensitive charge-generation layer (CGL) and a phosphorescent organic light-emitting diode (OLED) for producing clear images with a high resolution of 600 dots per inch. In this study, temperature-dependent electrical characterization was performed to analyze the interfacial modification of the cathodic-controlled upconverter. The result shows that the upconverter demonstrated a high conversion efficiency of 3.46% because of reduction in the injection barrier height at the interface between the CGL and the OLED.


Asunto(s)
Vasos Sanguíneos/diagnóstico por imagen , Diagnóstico por Imagen/métodos , Vasos Sanguíneos/patología , Electrodos , Humanos , Luz , Sustancias Luminiscentes/química , Sustancias Luminiscentes/uso terapéutico , Semiconductores , Temperatura
6.
Adv Mater ; 27(7): 1217-22, 2015 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-25504521

RESUMEN

Transparent organic upconversion devices are shown in a night-vision demonstration of a real object under near-infrared (NIR) illumination in the dark. An extraordinarily high current gain - reflecting the on-off switching effect - greater than 15 000 at a driving voltage of 3 V is demonstrated, indicating the high sensitivity to NIR light and potential of using the proposed upconverter in practical applications. A maximum luminance exceeding 1500 cd m(-2) at 7 V is achieved. Unlike previous studies, where 2D aperture projection is reported, the current study shows 3D images of real objects under NIR illumination in the dark.

7.
Mol Plant Microbe Interact ; 25(12): 1552-61, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22934563

RESUMEN

Both Colletotrichum and Magnaporthe spp. develop appressoria pigmented with melanin, which is essential for fungal pathogenicity. 1,8-Dihydroxynaphthalene (1,8-DHN) is believed to be polymerized to yield melanin around the appresorial cell wall through the oxidative activity of laccases. However, no 1,8-DHN laccase has yet been identified in either Colletotrichum or Magnaporthe spp. Here, we report a laccase gene, LAC2, that is involved in the appressorial melanization of Colletotrichum orbiculare, which causes cucumber anthracnose. LAC2 encodes a protein with a signal peptide and has high homology to fungal laccases. The conidial color of lac2 mutants is distinct from that of the C. orbiculare wild type, and the mutants are nonpathogenic. Notably, the mutant appressoria are defective in melanization, and a host invasion assay showed that the appressoria are nonfunctional. LAC2 was induced during appressorial melanization. These results suggest that LAC2 oxidizes 1,8-DHN in the appressoria. The LAC2 homologues of other fungi located in the same phylogenetic clade as LAC2 fully complemented the lac2 mutants. Interestingly, a LAC2 homologue, located in a different clade, complemented the conidial pigmentation but not appressorial melanization of the mutants, suggesting that the LAC2 function in appressorial melanization might only be conserved in laccases of the LAC2 clade.


Asunto(s)
Colletotrichum/enzimología , Cucumis sativus/microbiología , Lacasa/genética , Melaninas/metabolismo , Naftoles/metabolismo , Enfermedades de las Plantas/microbiología , Secuencia de Bases , Colletotrichum/genética , Colletotrichum/patogenicidad , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Técnicas de Inactivación de Genes , Prueba de Complementación Genética , Lacasa/metabolismo , Datos de Secuencia Molecular , Mutagénesis Insercional , Fenotipo , Filogenia , Pigmentación/genética , Señales de Clasificación de Proteína , Análisis de Secuencia de ADN , Esporas Fúngicas , Virulencia
8.
Nucl Med Commun ; 32(11): 989-96, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21862944

RESUMEN

OBJECTIVE: To investigate the prognostic impact of different 2-[fluorine-18]fluoro-2-deoxy-D-glucose positron emission tomography (¹8F-FDG PET) parameters in patients with advanced nasopharyngeal carcinoma (NPC). PATIENTS AND METHODS: A total of 196 patients with primary stage III-IVb NPC were included in the study. The following parameters derived from pretreatment ¹8F-FDG PET were determined: metabolic tumor volume and total lesion glycolysis (TLG) of the primary tumor, maximal standardized uptake value of the primary tumor and the neck lymph nodes. Multivariable Cox proportional hazards models were used to identify independent predictors of survival. RESULTS: Multivariable analysis demonstrated that TLG values greater than 330 independently predicted overall survival (P=0.0014) and disease-free survival (P=0.0005). We identified IVa-b stage and TLG values greater than 330 as independent predictors of local failure-free survival. In addition, a high maximal standardized uptake value of the neck lymph nodes (P=0.005), male sex (P=0.041), and stage IVa-b (P=0.009) independently predicted distant failure-free survival. A TLG cutoff value of 330 allowed a better stratification of overall survival and disease-free survival rates. A scoring system combining significant PET parameters and traditional prognostic factors was formulated to define distinct prognostic groups for local failure-free survival and distant failure-free survival. There was a stepwise decrease in the 5-year local (97.7, 90.4, and 47.3%, P<0.0001) and distant control rates (96.8, 88.5, 73.9, and 36.4%, P<0.0001) according to the distinct prognostic scores. CONCLUSION: In patients with advanced NPC, the prognostic significance of ¹8F-FDG PET parameters seems to depend on the specific endpoint. The combination of PET metabolic parameters with traditional risk factors may significantly improve prognostic stratification for this group of patients.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/mortalidad , Fluorodesoxiglucosa F18 , Neoplasias Nasofaríngeas/diagnóstico por imagen , Neoplasias Nasofaríngeas/mortalidad , Tomografía de Emisión de Positrones/métodos , Anciano , Anciano de 80 o más Años , Carcinoma , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/secundario , Femenino , Humanos , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/radioterapia , Pronóstico , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Radiofármacos , Análisis de Supervivencia , Resultado del Tratamiento , Carga Tumoral
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 27(1): 113-5, 2007 Jan.
Artículo en Chino | MEDLINE | ID: mdl-17390663

RESUMEN

A simple and highly sensitive new kinetic catalytic fluorimetric method was proposed for the determination of trace chromium (VI), based on the catalytic effect of trace amounts of chromium (VI) on the oxidation of Pyronine Y by hydrogen peroxide in acetic acid-sodium acetate buffer medium leading to a decrease in the fluorescence intensity. The optimum conditions and kinetic properties of the catalytic reaction were also studied. The apparent activation energy and the apparent rate constant are 159. 92 k * x mol(-1) and 5. 7X10-2 s-1 respectively. The linear range of the calibration curve is 0. 02-0. 24 microg x mL(-1) and the detection limit is 0. 012 microg x mL(-1). The present method was applied to the determination of chromium(VI) in river water, and industrial and electroplating waste water with good results.

10.
J Sep Sci ; 28(1): 92-7, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15688637

RESUMEN

A simple, rapid, reproducible, and universal non-aqueous capillary electrophoresis method has been developed for the separation and determination of three major active protoberberine alkaloids including berberine, palmatine, and jatrorrhizine within 7 min. The effects of the concentrations of acetic acid and electrolyte, the ratio of organic solvent, and the applied voltage on the separation were investigated. The optimum running buffer was composed of 50 mM ammonium acetate, 0.5% (v/v) acetic acid, and 10% (v/v) acetonitrile in methanol. The applied voltage was 18 kV. The analytes were detected by UV at 214 nm. The linearities between peak areas and the concentrations of the analytes were also investigated, and they exhibit excellent linear behavior over the concentration ranges (correlation coefficients: 0.9975-0.9986). The method was successfully applied to determine the three alkaloids in several families of herbal drugs (Rhizoma Coptidis, Cortex Berberidis, Cortex Phellodendri, Herba Chelidonii, Caulis Mahoniae) and their relevant medicinal preparations for the first time, and the recoveries of the three constituents ranged between 95.6-103.2% for berberine, 97.5-103.3% for palmatine, and 96.1 -103.6% for jatrorrhizine.


Asunto(s)
Alcaloides de Berberina/análisis , Berberina/análogos & derivados , Electroforesis Capilar/métodos , Berberina/análisis , Medicamentos Herbarios Chinos/análisis , Electroforesis Capilar/instrumentación , Electroforesis Capilar/estadística & datos numéricos , Plantas Medicinales/química , Reproducibilidad de los Resultados
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