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1.
Sensors (Basel) ; 18(9)2018 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-30154390

RESUMEN

Inertial Measurement Unit (IMU) calibration accuracy is easily affected by turntable errors, so the primary aim of this study is to reduce the dependence on the turntable's precision during the calibration process. Firstly, the indicated-output of the IMU considering turntable errors is constructed and with the introduction of turntable errors, the functional relationship between turntable errors and the indicated-output was derived. Then, based on a D-suboptimal design, a calibration method for simultaneously identifying the IMU error model parameters and the turntable errors was proposed. Simulation results showed that some turntable errors could thus be effectively calibrated and automatically compensated. Finally, the theoretical validity was verified through experiments. Compared with the traditional method, the method proposed in this paper can significantly reduce the influence of the turntable errors on the IMU calibration accuracy.

2.
J Am Chem Soc ; 138(32): 10157-62, 2016 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-27433782

RESUMEN

Here, we report DNA-induced polymer segregation and DNA island formation in binary block copolymer assemblies. A DNA diblock copolymer of polymethyl acrylate-block-DNA (PMA-b-DNA) and a triblock copolymer of poly(butadiene)-block-poly(ethylene oxide)-block-DNA (PBD-b-PEO-b-DNA) were synthesized, and each was coassembled with a prototypical amphiphilic polymer of poly(butadiene)-block-poly(ethylene oxide) (PBD-b-PEO). The binary self-assembly of PMA-b-DNA and PBD-b-PEO resulted in giant polymersomes with DNA uniformly distributed in the hydrophilic PEO shell. When giant polymersomes were connected through specific DNA interactions, DNA block copolymers migrated to the junction area, forming DNA islands within polymersomes. These results indicate that DNA hybridization can induce effective lateral polymer segregation in mixed polymer assemblies. The polymer segregation and local DNA enrichment have important implications in DNA melting properties, as mixed block copolymer assemblies with low DNA block copolymer contents can still exhibit useful DNA melting properties that are characteristic of DNA nanostructures with high DNA density.


Asunto(s)
ADN/química , Membrana Dobles de Lípidos/química , Polietilenglicoles/química , Polímeros/química , Acrilatos , Electroforesis en Gel de Poliacrilamida , Interacciones Hidrofóbicas e Hidrofílicas , Micelas , Microscopía Confocal , Nanoestructuras/química , Poliésteres/química , Agua/química
3.
Medicine (Baltimore) ; 102(32): e34497, 2023 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-37565897

RESUMEN

In recent years, the association between portal vein thrombosis and liver transplantation has extensive attention from physicians worldwide. However, there is no available literature on bibliometric analysis in this research area. Herein, we aimed to conduct a bibliometric analysis to identify the hotspots and frontiers of research related to portal vein thrombosis and liver transplantation. Documents published between 2002 and 2022 were retrieved and downloaded from the Web of Science Core Collection database. VOSviewer was utilized to generate a visualization network map of authors, nations, institutions, journals, and keyword co-occurrence/clustering. Additionaly, CiteSpace was used to analyze the keywords with the strongest bursts. A total of 1272 articles and reviews were extracted from the database. The author Marco Senzolo published the largest number of papers. The United States was the most prolific country, and Hope-Bochon (France) was the top productive institution. Liver Transplantation was the most prolific journal in the field. The most commonly identified keywords in the study were cirrhosis, risk factors, portal vein thrombosis, and management, as revealed by the keyword co-occurrence analysis. It is suggested that patients with cirrhosis, portal vein thrombosis prevention, and management measures for portal vein thrombosis have been prominet topics in recent years. Furthermore, an analysis of keywords with the strongest citation bursts highlighted pediatric liver transplantation, direct oral anticoagulants, and nonalcoholic fatty liver disease as current research trends. Research in portal vein thrombosis and liver transplantation exhibits a general upward trend. The latest hot topics within this area of study involve pediatric patients and nonalcoholic fatty liver disease.


Asunto(s)
Trasplante de Hígado , Enfermedad del Hígado Graso no Alcohólico , Trombosis , Humanos , Niño , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/cirugía , Vena Porta , Cirrosis Hepática , Bibliometría
5.
Front Microbiol ; 10: 2658, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31798569

RESUMEN

The soil-borne, asexual fungus Fusarium oxysporum f.sp. lycopersici (Fol) is the causal agent of tomato wilt disease. Autophagy plays a crucial role in the development and virulence of Fol. The Fol endosomal system is highly dynamic and has been shown to be associated with conidiogenesis and pathogenicity. Rab GTPases and the regulators are highly conserved in regulating autophagy and endocytosis in most eukaryotes. Identification and characterization of additional Rab regulators in fungal pathogens should facilitate the understanding of the autophagy and endocytosis in different filamentous fungi. Here, we have identified and characterized the yeast VPS9 homolog FolVPS9 in Fol. Targeted gene deletion showed that FolVPS9 is important for growth, conidiation and virulence in Fol. Cytological examination revealed that FolVps9 co-localized with FolVps21 (a marker of early endosome) and played a critical role in endocytosis and autophagosome degradation. Pull-down assays showed that FolVps9 interacted with FolVps21, which was also important for development and plant infection in Fol. Yeast two-hybrid, bimolecular fluorescence complementation and co-immunoprecipitation assays revealed that FolVps9 specifically interacts with the GDP-bound form of FolVps21. Furthermore, a constitutively active form of FolVps21 (Q72L) was able to rescue defects of ΔFolvps9 and ΔFolvps21 mutants. In summary, our study provides solid evidence that FolVps9 acts as a FolVps21 guanine nucleotide exchange factor (GEFs) to modulate endocytosis and autophagy, thereby controlling vegetative growth, asexual development and pathogenicity in Fol.

6.
Int J Med Mushrooms ; 20(11): 1087-1095, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30806232

RESUMEN

The optimal conditions for melanin extraction from Auricularia auricula-judae (Hei 29) fruiting bodies was determined on the basis of the extract yield of melanin, calculated by using a single-factor experiment and response surface methodology. Its antioxidant activities were also studied in vitro. Various optimal process conditions for melanin extraction were determined by using Design-Expert software: incubation temperature, 69.11°C; incubation time, 58.66 minutes; and incubation pH, 12.81. Under these conditions, the melanin yield was 2.59%. We found that the antioxidant activities of A. auricula-judae melanin in vitro were strong against DPPH radicals and superoxide anions. The rate of DPPH radical scavenging was 63.04% when the A. auricula-judae melanin concentration was 0.36 mg/mL; the rate of superoxide anion scavenging reached 39.79% when the concentration was 0.375 mg/mL. However, the antioxidant activity against hydroxyl radicals was somewhat weak; the rate of scavenging reached only 7.47% when the A. auricula-judae melanin concentration was 0.06 mg/mL.


Asunto(s)
Agaricales/química , Antioxidantes/farmacología , Basidiomycota/química , Melaninas/química , Antioxidantes/química , Cuerpos Fructíferos de los Hongos/química
7.
Biophys Chem ; 129(2-3): 148-62, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17574723

RESUMEN

A DNA-based model system is described for studying electron spin-spin interactions between a paramagnetic metal ion and a nitroxide spin label. The modified base deoxythymidine-EDTA (dT-EDTA) chelates the divalent or trivalent metal ion and produces a new feature in the circular dichroism (CD) spectra that makes it possible to monitor local DNA melting. Based on the results of optical and electron paramagnetic resonance (EPR) experiments, we find that the terminus of the DNA duplex that incorporates dT-EDTA and the spin-label melts at a higher temperature than the rest of the DNA duplex. EPR microwave progressive power saturation experiments performed at 77 K are consistent with the specific binding of Dy(III) at the EDTA site and an intramolecular dipole-dipole interaction between the nitroxide spin-label and the chelated Dy(III). This model system should be suitable for studying the relaxation properties of metal ions by saturation-recovery EPR.


Asunto(s)
Óxidos N-Cíclicos/química , ADN/química , Ácido Edético/análogos & derivados , Espectroscopía de Resonancia por Spin del Electrón , Modelos Químicos , Marcadores de Spin , Timidina/análogos & derivados , Dicroismo Circular , Crioprotectores/química , Ácido Edético/química , Electrones , Microondas , Oligodesoxirribonucleótidos/química , Espectrofotometría Ultravioleta , Termodinámica , Timidina/química
8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 24(4): 440-2, 2007 Aug.
Artículo en Zh | MEDLINE | ID: mdl-17680538

RESUMEN

OBJECTIVE: To detect novel mutations in the fibrillin 1 (FBN1) and transforming growth factor beta receptor type II (TGFBR2) genes by screening the genes from 14 patients with Marfan syndrome. METHODS: Denaturing high performance liquid chromatography (DHPLC) was introduced to screen for FBN1 and TGFBR2 mutations exon-by-exon. The DNA amplification fragments which DHPLC elution profiles showed different from the corresponding normal elution profile were sequenced to identify the positions and types of mutations. Restriction fragment length polymorphism (RFLP) was employed to further prove the mutations when needed. RESULTS: Two gene mutations of the FBN1 were found in the patients with Marfan syndrome. They were a novel substitutional mutation (Intron29 +4A > T) of FBN1 and a recurrent nonsense mutation (8080C >T) of FBN1. CONCLUSION: Intron29 +4A > T and 8080C > T of FBN1 are possibly the pathogenesis of the MFS patients.


Asunto(s)
Síndrome de Marfan/genética , Proteínas de Microfilamentos/genética , Mutación , Proteínas Serina-Treonina Quinasas/genética , Receptores de Factores de Crecimiento Transformadores beta/genética , Adolescente , Secuencia de Bases , Análisis Mutacional de ADN , Femenino , Fibrilina-1 , Fibrilinas , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Receptor Tipo II de Factor de Crecimiento Transformador beta
9.
Environ Sci Pollut Res Int ; 24(32): 25000-25009, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28920176

RESUMEN

Antifungal metabolites produced by Bacillus sp. W10, which was previously isolated from the tomato rhizosphere, were investigated. Strain W10 was identified as Bacillus amyloliquefaciens by analysis of its 16S rDNA and gyrB gene partial sequences. PCR analysis showed the presence of fenB, sfp, and ituD genes, coding for fengycin, surfactin, and iturin, respectively. A novel small antifungal peptide, designated 5240, produced by this strain was isolated by ammonium sulfate precipitation and Superdex 200 gel filtration chromatography. The 5240 peptide was stable at 100 °C for 20 min and remained active throughout a wide pH range (4-10). The antagonistic activity was not affected by protease K and trypsin. The purified 5240 peptide exhibited a broad inhibitory spectrum against various plant pathogenic fungi and was identified as iturin A (C14-C16). Moreover, matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry indicated the presence of fengycin A (C14-C15), fengycin B (C16-C17), and surfactin (C13-C16) isoforms in supernatants from strain W10. These results suggest that B. amyloliquefaciens W10 has significant potential as a biocontrol agent.


Asunto(s)
Bacillus amyloliquefaciens/genética , Cromatografía en Gel/métodos , Girasa de ADN/genética , ADN Bacteriano/genética , Precipitación Fraccionada/métodos , ARN Ribosómico 16S/genética , Antifúngicos/aislamiento & purificación , Girasa de ADN/metabolismo , ADN Bacteriano/metabolismo , ARN Ribosómico 16S/metabolismo , Análisis de Secuencia de ADN , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
11.
Zhong Xi Yi Jie He Xue Bao ; 2(5): 333-6, 2004 Sep.
Artículo en Zh | MEDLINE | ID: mdl-15383251

RESUMEN

OBJECTIVE: To explore the nature of pathology of sluggishness of lung-defensive qi and to offer objective experimental indexes for weifen syndrome (defensive phase syndrome). METHODS: According to the completely random design, the plasma levels of vasoactive intestinal peptide (VIP) and thromboxane B2 (TX2) of 19 patients with weifen syndrome and 13 patients with qifen syndrome (qi phase syndrome) were detected by radioimmunoassay. The plasma levels of VIP and TX2 at different stages of weifen syndrome and qifen syndrome were observed. RESULTS: The plasma levels of VIP in weifen syndrome and in the late stage of weifen syndrome increased greatly at different stages as compared to qifen syndrome and the blank group (P < 0.01), while the plasma level of TX2 of weifen syndrome was higher only at the late stage than the blank group and qifen syndrome (P < 0.01). As for the levels of VIP and TX2 in weifen syndrome with different internal organs infected, there was no significant difference (P > 0.05). CONCLUSION: VIP may be an index reflecting the pathology of weifen syndrome, and it is one of the material foundations of sluggishness of lung-defensive qi, but it has nothing to do with the infected internal organs. The level of TX2 increases only after the fever of patients with weifen syndrome subsided, so it can not be the basis for diagnosis of the early stage of weifen syndrome. It doesn't increase in qifen syndrome either, the mechanism remains to be further studied.


Asunto(s)
Enfermedades Pulmonares/sangre , Tromboxano B2/sangre , Péptido Intestinal Vasoactivo/sangre , Femenino , Humanos , Enfermedades Pulmonares/patología , Masculino , Radioinmunoensayo , Síndrome
13.
Zhongguo Gu Shang ; 26(6): 526-9, 2013 Jun.
Artículo en Zh | MEDLINE | ID: mdl-24015664

RESUMEN

Dynamic stabilization technology has increasingly become the hot spot in basic and clinical research for treating lumbar degenerative diseases. As one kind of dynamic stabilization technology,dynamic neutralization system (Dynesys) keeps the spinal motion ability and improve clinical symptoms of patients, moreover, it shows a certain advantage in delaying the degeneration of adjacent segments. From the available documents,the preliminary biomechanical and clinical results of Dynesys were optimistically, it has become another choice in treating the lumbar degenerative diseases besides the lumbar fusion, and it primarily applies to the treatment of mild to moderate lumbar degenerative disease. However, it lacks a mechanism to maintain and restore the lumbar lordosis and patients need active stretching to achieve lordosis. What's more, how to extend the service life and prevent complications remain to be solved, the long-term effect and the mechanism of delaying the adjacent segment degeneration need further investigation. In this article, the design principle, biomechanical research, clinical outcome and clinical application of Dynesys was reviewed.


Asunto(s)
Vértebras Lumbares/cirugía , Enfermedades de la Columna Vertebral/cirugía , Animales , Humanos
14.
Methods Mol Biol ; 1025: 207-24, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23918340

RESUMEN

We have recently developed a universal procedure to functionalize inorganic nanoparticles with a dense layer of DNA through the self-assembly of DNA block copolymers and nanoparticles. This functionalization strategy allows one to combine the useful physical properties of inorganic nanoparticle with the enhanced DNA binding properties that originate from the high surface DNA density. In particular, the hybrid nanostructures exhibit orders of magnitude higher binding constants than regular DNA strands. This chapter presents a detailed protocol for the preparation and characterization of DNA block copolymer assemblies loaded with nanoparticles.


Asunto(s)
ADN/química , Biología Molecular/métodos , Nanopartículas/química , Polímeros/química , Materiales Biocompatibles/química , Compuestos Férricos/química , Nanoestructuras/química , Oligonucleótidos/química , Poliestirenos/química , Propiedades de Superficie
16.
Artículo en Inglés | MEDLINE | ID: mdl-22223509

RESUMEN

DNA-conjugated metal nanoparticles have attracted enormous attention for biological and medical applications, owing to their unusual DNA melting characteristics as well as unique optical and catalytic properties. The combination of these unique properties has not only led to the development of DNA-detection technologies with remarkably high selectivity and sensitivity, but also to the development of gene therapeutic agents with high efficacy and efficiency. In this review, we present a comprehensive coverage on their applications in detecting, manipulating, and delivering genes.


Asunto(s)
ADN/química , Técnicas de Transferencia de Gen , Oro/química , Nanopartículas del Metal/química , Plata/química , Animales , Sistemas de Liberación de Medicamentos/métodos , Humanos , Análisis Espectral
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