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1.
Medicine (Baltimore) ; 102(45): e35948, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37960781

RESUMEN

RATIONALE: FLAIR-hyperintense lesions in anti-myelin oligodendrocyte glycoprotein (MOG)-associated encephalitis with seizures (FLAMES) is a rare clinical phenotype of anti-MOG; immunoglobulin G-associated disease is often misdiagnosed as viral encephalitis in the early stages. Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is an autoimmune encephalitis caused by antibodies targeting the GluN1 subunit of the NMDAR. The coexistence of anti-NMDAR encephalitis and FLAMES is very rare. PATIENT CONCERNS: A 20-year-old female patient initially presented with seizures accompanied by daytime sleepiness. DIAGNOSES: Magnetic resonance imaging revealed FLAIR-hyperintense lesions in unilateral cerebral cortex. NMDAR antibodies was positive in the cerebrospinal fluid and MOG antibodies in the serum. INTERVENTIONS: Steroid therapy was administrated. OUTCOMES: The symptoms completely relieved. At 6-month follow-up, the patient's condition remained stable. Magnetic resonance imaging showed no abnormalities in the unilateral cerebral cortex. CONCLUSION: When a patient with anti-NMDAR encephalitis or FLAMES is encountered in clinical practice, the coexistence of these diseases with double-positive anti-NMDAR and MOG antibodies should be considered and adopt appropriate evaluation and treatment.


Asunto(s)
Encefalitis Antirreceptor N-Metil-D-Aspartato , Femenino , Humanos , Adulto Joven , Encefalitis Antirreceptor N-Metil-D-Aspartato/complicaciones , Encefalitis Antirreceptor N-Metil-D-Aspartato/diagnóstico , Encefalitis Antirreceptor N-Metil-D-Aspartato/tratamiento farmacológico , Autoanticuerpos , Imagen por Resonancia Magnética , Glicoproteína Mielina-Oligodendrócito , Convulsiones/complicaciones
2.
J Mol Model ; 29(6): 181, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37198340

RESUMEN

CONTEXT: Ferroelectric ceramic polymer composites have become the preferred electrocaloric materials due to their light weight and high polarization strength. But the mechanical properties were desired to be improved. In this study, the polyvinylidene fluoride trifluoro ethylene chloride (PVTC) and barium titanate (BT) composites were prepared, and the microstructure and mechanical properties were investigated by molecular dynamics simulations and experiments. It was found that with the increase of BT ceramic content in the composites, the yield stress is significantly reduced, which can be reduced by 16.07%. By comparing with the experimental data, the agglomeration and stress mechanism of the composites were proposed. METHOD: The microstructure of the composite was analyzed using radial distribution function, self-diffusion coefficient, and glass transition temperature. The agglomeration mechanism of the composite was revealed from the microscopic point of view, and the rationality of the agglomeration behavior was verified by experiments. The calculations were performed by Material Studio 2019 software and the COMPASS force field was adopted.

3.
Nat Commun ; 14(1): 2033, 2023 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-37041201

RESUMEN

Thiosulfate oxidation by microbes has a major impact on global sulfur cycling. Here, we provide evidence that bacteria within various Roseobacter lineages are important for thiosulfate oxidation in marine biofilms. We isolate and sequence the genomes of 54 biofilm-associated Roseobacter strains, finding conserved sox gene clusters for thiosulfate oxidation and plasmids, pointing to a niche-specific lifestyle. Analysis of global ocean metagenomic data suggests that Roseobacter strains are abundant in biofilms and mats on various substrates, including stones, artificial surfaces, plant roots, and hydrothermal vent chimneys. Metatranscriptomic analysis indicates that the majority of active sox genes in biofilms belong to Roseobacter strains. Furthermore, we show that Roseobacter strains can grow and oxidize thiosulfate to sulfate under both aerobic and anaerobic conditions. Transcriptomic and membrane proteomic analyses of biofilms formed by a representative strain indicate that thiosulfate induces sox gene expression and alterations in cell membrane protein composition, and promotes biofilm formation and anaerobic respiration. We propose that bacteria of the Roseobacter group are major thiosulfate-oxidizers in marine biofilms, where anaerobic thiosulfate metabolism is preferred.


Asunto(s)
Roseobacter , Tiosulfatos , Tiosulfatos/metabolismo , Roseobacter/genética , Roseobacter/metabolismo , Anaerobiosis , Proteómica , Biopelículas
4.
Imeta ; 2(3): e121, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38867926

RESUMEN

The taxonomic structure of biofilms on 0.3-mm microplastics differed significantly from that on 3-mm microplastics or glass particles. Compared with the 3-mm microplastics, biofilms on 0.3-mm microplastics were enriched for genes involved in flagellar-based motility and chemotaxis, pointing to a more 'mobile' community. The association between motility and bacterial colonization of 0.3-mm microplastics was observed through laboratory experiments using isolated strains.

5.
Sensors (Basel) ; 22(17)2022 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-36080954

RESUMEN

Instance segmentation has been developing rapidly in recent years. Mask R-CNN, a two-stage instance segmentation approach, has demonstrated exceptional performance. However, the masks are still very coarse. The downsampling operation of the backbone network and the ROIAlign layer loses much detailed information, especially from large targets. The sawtooth effect of the edge mask is caused by the lower resolution. A lesser percentage of boundary pixels leads to not-fine segmentation. In this paper, we propose a new method called Boundary Refine (BRefine) that achieves high-quality segmentation. This approach uses FCN as the foundation segmentation architecture, and forms a multistage fusion mask head with multistage fusion detail features to improve mask resolution. However, the FCN architecture causes inconsistencies in multiscale segmentation. BRank and sort loss (BR and S loss) is proposed to solve the problems of segmentation inconsistency and the difficulty of boundary segmentation. It is combined with rank and sort loss, and boundary region loss. BRefine can handle hard-to-partition boundaries and output high-quality masks. On the COCO, LVIS, and Cityscapes datasets, BRefine outperformed Mask R-CNN by 3.0, 4.2, and 3.5 AP, respectively. Furthermore, on the COCO dataset, the large objects improved by 5.0 AP.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Procesamiento de Imagen Asistido por Computador/métodos
6.
Genes (Basel) ; 13(6)2022 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-35741812

RESUMEN

Marine biofilms are a collective of microbes that can grow on many different surfaces immersed in marine environments. Estimating the microbial richness and specificity of a marine biofilm community is a challenging task due to the high complexity in comparison with seawater. Here, we compared the resolution of full-length 16S rRNA gene sequencing technique of a PacBio platform for microbe identification in marine biofilms with the results of partial 16S rRNA gene sequencing of traditional Illumina PE250 platform. At the same time, the microbial richness, diversity, and composition of adjacent seawater communities in the same batch of samples were analyzed. Both techniques revealed higher species richness, as reflected by the Chao1 index, in the biofilms than that in the seawater communities. Moreover, compared with Illumina sequencing, PacBio sequencing detected more specific species for biofilms and less specific species for seawater. Members of Vibrio, Arcobacter, Photobacterium, Pseudoalteromonas, and Thalassomonas were significantly enriched in the biofilms, which is consistent with the previous understanding of species adapted to a surface-associated lifestyle and validates the taxonomic analyses in the current study. To conclude, the full-length sequencing of 16S rRNA genes has probably a stronger ability to analyze more complex microbial communities, such as marine biofilms, the species richness of which has probably been under-estimated in previous studies.


Asunto(s)
Biopelículas , Genes de ARNr , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN/métodos
7.
Biomed Chromatogr ; 30(10): 1632-40, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27061415

RESUMEN

A selective and sensitive HPLC-MS/MS method was developed for the simultaneous determination of cucurbitacin IIa (cuIIa) and cucurbitacin IIb (cuIIb), the major bioactive cucurbitacins of Hemsleya amabilis, in rat plasma using euphadienol as internal standard (IS). After liquid-liquid extraction with dichloromethane, separation was achieved on a Syncronis HPLC C18 column (150 mm × 4.6 mm, 5 µm) using an isocratic mobile phase system consisting of acetonitrile-water (85:15, v/v) at a flow rate of 0.6 mL/min with a split ratio of 1:2. Detection was performed on a TSQ Quantum Ultra mass spectrometer equipped with an positive-ion electrospray ionization source. The lower limits of quantification (LLOQs) were 0.25 and 0.15 ng/mL for cuIIa and cuIIb, respectively. The intra- and inter-day precision was <11.5% for the LLOQs and each quality control level of the analytes, and accuracy was between -9.1 and 7.6%. The extraction recoveries of the analytes and IS from rat plasma were all >87.1%. The method was fully validated and applied to compare the pharmacokinetic profiles of the two cucurbitacins in rat plasma after oral administration of H. amabilis extract between normal and indomethacin-induced rats. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cucurbitacinas/farmacocinética , Indometacina/administración & dosificación , Espectrometría de Masas en Tándem/métodos , Animales , Límite de Detección , Ratas , Estándares de Referencia , Reproducibilidad de los Resultados
8.
Ying Yong Sheng Tai Xue Bao ; 24(10): 2912-6, 2013 Oct.
Artículo en Chino | MEDLINE | ID: mdl-24483087

RESUMEN

According to the hydrological and morphological characteristics, He'nan Province was divided into mountainous region and plain region. The level of rich water, infiltration modulus of precipitation, fertilization level per unit area, proportions of vegetable planting area, and soil texture were selected as the common indices, and the slope and groundwater depth were selected as specific indices to assess the groundwater vulnerability to nitrate. Principal component regression analysis was adopted to determine the index weights, and the spatial distribution of groundwater vulnerability to nitrate in He'nan Province was assessed with ArcGIS 9.2. In the Province, the groundwater vulnerability to nitrate was mainly at low and medium level, and the region with this vulnerability level accounted for 68.4% of the total. The high vulnerability region accounted for 19.8%, and the extremely high vulnerability region occupied 11.8%. The main factors affecting the groundwater vulnerability to nitrate in plain region were soil texture, fertilization level, and infiltration modulus of precipitation, while those in mountainous region were fertilization level, soil texture, and slope. This study provided a theoretical basis for reasonable fertilization and agricultural environment management.


Asunto(s)
Monitoreo del Ambiente/métodos , Agua Subterránea/análisis , Nitratos/análisis , Contaminantes Químicos del Agua/análisis , China , Fertilizantes , Análisis de Componente Principal , Análisis de Regresión , Medición de Riesgo
9.
IEEE Trans Biomed Eng ; 57(1): 145-54, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19846365

RESUMEN

The therapeutic efficacy of neurological agents is severely limited, because large compounds do not cross the blood-brain barrier (BBB). Focused ultrasound (FUS) sonication in the presence of microbubbles has been shown to temporarily open the BBB, allowing systemically administered agents into the brain. Until now, polydispersed microbubbles (1-10 microm in diameter) were used, and, therefore, the bubble sizes better suited for inducing the opening remain unknown. Here, the FUS-induced BBB opening dependence on microbubble size is investigated. Bubbles at 1-2 and 4-5 microm in diameter were separately size-isolated using differential centrifugation before being systemically administered in mice (n = 28). The BBB opening pressure threshold was identified by varying the peak-rarefactional pressure amplitude. BBB opening was determined by fluorescence enhancement due to systemically administered, fluorescent-tagged, 3-kDa dextran. The identified threshold fell between 0.30 and 0.46 MPa in the case of 1-2 microm bubbles and between 0.15 and 0.30 MPa in the 4-5 microm case. At every pressure studied, the fluorescence was greater with the 4-5 mum than with the 1-2 microm bubbles. At 0.61 MPa, in the 1-2 microm bubble case, the fluorescence amount and area were greater in the thalamus than in the hippocampus. In conclusion, it was determined that the FUS-induced BBB opening was dependent on both the size distribution in the injected microbubble volume and the brain region targeted.


Asunto(s)
Barrera Hematoencefálica/diagnóstico por imagen , Sistemas de Liberación de Medicamentos/métodos , Microburbujas , Ultrasonografía/métodos , Animales , Química Encefálica , Ecoencefalografía , Histocitoquímica , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Permeabilidad
10.
Ultrasound Med Biol ; 36(1): 58-67, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19900750

RESUMEN

Focused ultrasound (FUS) is hereby shown to noninvasively and selectively deliver compounds at pharmacologically relevant molecular weights through the opened blood-brain barrier (BBB). A complete examination on the size of the FUS-induced BBB opening, the spatial distribution of the delivered agents and its dependence on the agent's molecular weight were imaged and quantified using fluorescence microscopy. BBB opening in mice (n=13) was achieved in vivo after systemic administration of microbubbles and subsequent application of pulsed FUS (frequency: 1.525MHz, peak-rarefactional pressure in situ: 570 kPa) to the left murine hippocampus through the intact skin and skull. BBB-impermeant, fluorescent-tagged dextrans at three distinct molecular weights spanning over several orders of magnitude were systemically administered and acted as model therapeutic compounds. First, dextrans of 3 and 70 kDa were delivered trans-BBB while 2000 kDa dextran was not. Second, compared with 70 kDa dextran, a higher concentration of 3 kDa dextran was delivered through the opened BBB. Third, the 3 and 70 kDa dextrans were both diffusely distributed throughout the targeted brain region. However, high concentrations of 70 kDa dextran appeared more punctated throughout the targeted region. In conclusion, FUS combined with microbubbles opened the BBB sufficiently to allow passage of compounds of at least 70 kDa, but not greater than 2000 kDa into the brain parenchyma. This noninvasive and localized BBB opening technique could, thus, provide a unique means for the delivery of compounds of several magnitudes of kDa that include agents with shown therapeutic promise in vitro but whose in vivo translation has been hampered by their associated BBB impermeability. (E-mail: ek2191@columbia.edu).


Asunto(s)
Barrera Hematoencefálica/metabolismo , Dextranos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Terapia por Ultrasonido/métodos , Animales , Permeabilidad Capilar , Dextranos/química , Fluorescencia , Hipocampo/anatomía & histología , Hipocampo/irrigación sanguínea , Hipocampo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Microburbujas , Microscopía Fluorescente , Peso Molecular , Terapia por Ultrasonido/instrumentación
11.
Artículo en Inglés | MEDLINE | ID: mdl-18986870

RESUMEN

High frame-rate ultrasound RF data acquisition has been proved to be critical for novel cardiovascular imaging techniques, such as high-precision myocardial elastography, pulse wave imaging (PWI), and electromechanical wave imaging (EWI). To overcome the frame-rate limitations on standard clinical ultrasound systems, we developed an automated method for multi-sector ultrasound imaging through retrospective electrocardiogram (ECG) gating on a clinically used open architecture system. The method achieved both high spatial (64 beam density) and high temporal resolution (frame rate of 481 Hz) at an imaging depth up to 11 cm and a 100% field of view in a single breath-hold duration. Full-view imaging of the left ventricle and the abdominal aorta of healthy human subjects was performed using the proposed technique in vivo. ECG and ultrasound RF signals were simultaneously acquired on a personal computer (PC). Composite, full-view frames both in RF- and B-mode were reconstructed through retrospective combination of seven small (20%) juxtaposed sectors using an ECG-gating technique. The axial displacement of the left ventricle, in both long-axis and short-axis views, and that of the abdominal aorta, in a long-axis view, were estimated using a RF-based speckle tracking technique. The electromechanical wave and the pulse wave propagation were imaged in a ciné-loop using the proposed imaging technique. Abnormal patterns of such wave propagation can serve as indicators of early cardiovascular disease. This clinical system could thus expand the range of applications in cardiovascular elasticity imaging for quantitative, noninvasive diagnosis of myocardial ischemia or infarction, arrhythmia, abdominal aortic aneurysms, and early-stage atherosclerosis.


Asunto(s)
Algoritmos , Ecocardiografía/métodos , Diagnóstico por Imagen de Elasticidad/métodos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
Ultrason Imaging ; 30(3): 189-200, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19149463

RESUMEN

The spatio-temporal nature of focused ultrasound-induced blood-brain barrier (BBB) opening as a brain drug delivery method was investigated in Alzheimer's disease model mice. The left hippocampus of transgenic (APP/PS1, n = 3) and nontransgenic (n = 3) mice was sonicated (frequency: 1.525 MHz, peak-negative pressure: 600 kPa, pulse length: 20 ms, duty cycle: 20%, duration: 1 min) in vivo, through their intact skin and skull, after intravenous injection of microbubbles (SonoVue; 25 microl). Sequential, high-field MR images (9.4 Tesla) were acquired before and after injection of gadolinium (Omniscan, 0.75 ml, molecular weight: 573.7 Da) on two separate days for each mouse. Gadolinium deposits through the ultrasound-induced BBB opening in the left hippocampus revealed significant contrast-enhancement in the MRI. On the following day, MRI revealed significant BBB closure within the same region. However, the BBB opening extent and BBB closing timeline varied in different regions within the same sonicated location. This indicates that opening and closing were dependent on the brain region targeted. No significant difference in BBB opening or closing behaviors was observed between the APP/PS1 and the nontransgenic mice. In conclusion, a BBB-impermeable molecule was noninvasively, transiently and reproducibly delivered to the hippocampus of Alzheimer's APP/PS1 mice.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Barrera Hematoencefálica/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Hipocampo/metabolismo , Imagen por Resonancia Magnética , Terapia por Ultrasonido/métodos , Animales , Medios de Contraste/administración & dosificación , Gadolinio DTPA/administración & dosificación , Hipocampo/irrigación sanguínea , Ratones , Ratones Transgénicos , Fosfolípidos/administración & dosificación , Hexafluoruro de Azufre/administración & dosificación
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