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1.
Proc Natl Acad Sci U S A ; 121(32): e2403652121, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39083419

RESUMEN

Leucine-rich glioma-inactivated protein 1 (LGI1), a secretory protein in the brain, plays a critical role in myelination; dysfunction of this protein leads to hypomyelination and white matter abnormalities (WMAs). Here, we hypothesized that LGI1 may regulate myelination through binding to an unidentified receptor on the membrane of oligodendrocytes (OLs). To search for this hypothetic receptor, we analyzed LGI1 binding proteins through LGI1-3 × FLAG affinity chromatography with mouse brain lysates followed by mass spectrometry. An OL-specific membrane protein, the oligodendrocytic myelin paranodal and inner loop protein (OPALIN), was identified. Conditional knockout (cKO) of OPALIN in the OL lineage caused hypomyelination and WMAs, phenocopying LGI1 deficiency in mice. Biochemical analysis revealed the downregulation of Sox10 and Olig2, transcription factors critical for OL differentiation, further confirming the impaired OL maturation in Opalin cKO mice. Moreover, virus-mediated re-expression of OPALIN successfully restored myelination in Opalin cKO mice. In contrast, re-expression of LGI1-unbound OPALIN_K23A/D26A failed to reverse the hypomyelination phenotype. In conclusion, our study demonstrated that OPALIN on the OL membrane serves as an LGI1 receptor, highlighting the importance of the LGI1/OPALIN complex in orchestrating OL differentiation and myelination.


Asunto(s)
Diferenciación Celular , Péptidos y Proteínas de Señalización Intracelular , Ratones Noqueados , Oligodendroglía , Animales , Oligodendroglía/metabolismo , Oligodendroglía/citología , Ratones , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Vaina de Mielina/metabolismo , Proteínas de la Mielina/metabolismo , Proteínas de la Mielina/genética
2.
Inorg Chem ; 63(2): 1378-1387, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38164710

RESUMEN

The zero-valent iron (ZVI) has attracted increasing attention due to the enhanced reactivity of ZVI to uranium wastewater. However, ZVI practical application is hampered due to its susceptibility to oxidation and the formation of passivation layers during storage and in situ restoration. To address these issues, we used a biosulfuration approach to modify ZVI for application in uranium ore wastewater treatment. A series of physicochemical characterization tools and photoelectronic analyses showed that BS-ZVI considerably increased carrier separation efficiency and visible light absorption capacity, resulting in a significant photoassisted enhancement effect on uranium extraction. Accordingly, the uranium removal efficiency of BS-ZVI reached 91% within 60 min, and its maximum adsorption capacity was 336.3 mg/g. By analyzing the mechanism, the improved U(VI) removal performance was mostly responsible on the dissolution of the passivation layer on the surface of ZVI, the generation of Fe(II) and FeS, and the important role of Shewanella putrefaciens extracellular polymers (EPS). Overall, the BS-ZVI biohybrid merges with the high activity of ZVI, bio-FeS, and self-regeneration ability of bacteria, expanding a promising new approach for sustainable treatment of uranium mine wastewater.

3.
Sensors (Basel) ; 24(12)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38931573

RESUMEN

The visual measurement of deep holes in composite material workpieces constitutes a critical step in the robotic assembly of aerospace components. The positioning accuracy of assembly holes significantly impacts the assembly quality of components. However, the complex texture of the composite material surface and mutual interference between the imaging of the inlet and outlet edges of deep holes significantly challenge hole detection. A visual measurement method for deep holes in composite materials based on the radial penalty Laplacian operator is proposed to address the issues by suppressing visual noise and enhancing the features of hole edges. Coupled with a novel inflection-point-removal algorithm, this approach enables the accurate detection of holes with a diameter of 10 mm and a depth of 50 mm in composite material components, achieving a measurement precision of 0.03 mm.

4.
Sensors (Basel) ; 24(7)2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38610270

RESUMEN

The robotic drilling of assembly holes is a crucial process in aerospace manufacturing, in which measuring the normal of the workpiece surface is a key step to guide the robot to the correct pose and guarantee the perpendicularity of the hole axis. Multiple laser displacement sensors can be used to satisfy the portable and in-site measurement requirements, but there is still a lack of accurate analysis and layout design. In this paper, a simplified parametric method is proposed for multi-sensor normal measurement devices with a symmetrical layout, using three parameters: the sensor number, the laser beam slant angle, and the laser spot distribution radius. A normal measurement error distribution simulation method considering the random sensor errors is proposed. The measurement error distribution laws at different sensor numbers, the laser beam slant angle, and the laser spot distribution radius are revealed as a pyramid-like region. The influential factors on normal measurement accuracy, such as sensor accuracy, quantity and installation position, are analyzed by a simulation and verified experimentally on a five-axis precision machine tool. The results show that increasing the laser beam slant angle and laser spot distribution radius significantly reduces the normal measurement errors. With the laser beam slant angle ≥15° and the laser spot distribution radius ≥19 mm, the normal measurement error falls below 0.05°, ensuring normal accuracy in robotic drilling.

5.
Virus Genes ; 54(6): 746-755, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30229544

RESUMEN

Japanese encephalitis is a zoonotic, mosquito-borne, infectious disease caused by Japanese encephalitis virus (JEV), which is prevalent in China. At present, there are no specific drugs or therapies for JEV infection, which can only be treated symptomatically. Lentivirus-mediated RNA interference (RNAi) is a highly efficient method to silence target genes. In this study, two lentiviral shRNA, LV-C and LV-NS5, targeting the conserved viral gene sequences were used to inhibit different JEV genotypes strains in BHK21 cells and mice. The results showed that LV-C significantly inhibited JEV genotype I and genotype III strains in cells and mice. Quantitative RT-PCR analysis showed that JEV mRNA were reduced by 83.2-90.9% in cells by LV-C and that flow cytometry analysis confirmed the inhibitory activity of LV-C. The viral titers were reduced by about 1000-fold in cells and the brains of suckling mice by LV-C, and the pretreatment of LV-C protected 60-80% of mice against JEV-induced lethality. The inhibitory activities of LV-NS5 in cells and mice were weaker than those of LV-C. These results indicate that RNAi targeting of the two conserved viral gene sequences had significantly suppressed the replication of different JEV genotypes strains in vitro and in vivo, highlighting the feasibility of RNAi targeting of conserved viral gene sequences for controlling JEV infection.


Asunto(s)
Virus de la Encefalitis Japonesa (Especie)/genética , Encefalitis Japonesa/virología , Genes Virales , Genotipo , Interferencia de ARN , Animales , Secuencia Conservada , Cricetinae , Encefalitis Japonesa/mortalidad , Regulación Viral de la Expresión Génica , Ratones , ARN Interferente Pequeño/genética , Ensayo de Placa Viral , Replicación Viral
6.
J Nat Prod ; 81(4): 913-917, 2018 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-29469570

RESUMEN

Two new acylated ß-hydroxynitrile glycosides, ribemansides A (1) and B (2), were isolated from the aerial parts of Ribes manshuricum. Their structures were elucidated by comprehensive spectroscopic analysis. Ribemansides A and B inhibited transforming growth factor ß1 (TGF-ß1)-induced expression of α-smooth muscle actin, fibronectin release, and changes in cell morphology in the human proximal tubular epithelial cell line (human kidney-2, HK-2). Further biological evaluation demonstrated that both 1 and 2 inhibit the activity of canonical transient receptor potential cation channel 6 (TRPC6), with IC50 values of 24.5 and 25.6 µM, respectively. The antifibrogenic effect of these compounds appears to be mediated through TRPC6 inhibition, since the TRPC6 inhibitor, SAR7334, also suppressed TGF-ß1-induced fibrogenesis in HK-2 cells.


Asunto(s)
Glicósidos/farmacología , Extractos Vegetales/farmacología , Ribes/química , Canal Catiónico TRPC6/antagonistas & inhibidores , Factor de Crecimiento Transformador beta1/metabolismo , Actinas/metabolismo , Células Cultivadas , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Fibronectinas/metabolismo , Glicósidos/química , Humanos , Extractos Vegetales/química
7.
Mycologia ; 107(3): 505-11, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25724995

RESUMEN

A new species of Meliolinites (fossil Meliolaceae), M. buxi sp. nov., is reported from the Oligocene Ningming Formation of Guangxi, South China. The fungus has hyphopodia characteristics of extant Meliolaceae, such as thick-walled, branching hyphae with appressoria and phialides. However, these fossils entirely lack mycelial or perithecial setae and have only a few phialides, thereby distinguishing the new species from most known species. The fungus was discovered on the adaxial and abaxial cuticles of several fossilized Buxus leaves. Thickening and twisting of cell walls in the Buxus leaf cuticle, along with the parasitic feeding strategy of the extant Meliolaceae, suggest that a parasitic interaction between Buxus and M. buxi seems feasible. The distribution of modern Meliolaceae suggests that they live in warm, humid subtropical-tropical climates. It is possible that the presence of M. buxi indicates a similar climatic condition. The co-occurrence of large-leaf Buxus and floristic comparisons of the Ningming assemblage also corroborate this conclusion.


Asunto(s)
Ascomicetos/aislamiento & purificación , Buxus/microbiología , Fósiles/anatomía & histología , Ascomicetos/clasificación , Ascomicetos/crecimiento & desarrollo , China , Hifa/clasificación , Hifa/crecimiento & desarrollo , Hifa/aislamiento & purificación , Hojas de la Planta/microbiología
8.
Int Immunopharmacol ; 127: 111458, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38160565

RESUMEN

BACKGROUND: Sepsis is a disorder characterized by host inflammation and is caused by systemic infection. The inflammatory cytokine storm results in platelet overactivation, leading to coagulation dysfunction and thrombosis, but the underlying mechanism remains poorly understood. Recent evidence has shown that the Wnt/ß-catenin signaling pathway is related to sepsis, but its role and mechanism in sepsis complicated with deep vein thrombosis (DVT) are unclear. METHODS: In this study, a cecal ligation and puncture (CLP)-induced sepsis model and DVT mouse model were constructed by inferior vena cava ligation. The levels of serum inflammatory factors and adhesion molecules were measured in each group, and the thrombus weight and size, hematoxylin-eosin staining, collagen fiber tissue, and transcriptome of the venous wall were analyzed. The activation of the Wnt/ß-catenin signal was evaluated by quantitative real-time polymerase chain reaction, Western blotting, ELISA, and immunohistochemical and immunofluorescence methods. RESULTS: Sepsis significantly promoted the formation of venous wall collagen fibers and DVT. In addition, Porcn significantly upregulated and activated the Wnt/ß-catenin signaling pathway in sepsis mouse models with DVT. In contrast, the Wnt signaling inhibitor LGK974 was found to improve the survival rate, decrease thrombosis, and inhibit the expression of inflammation and adhesion molecules in sepsis mice with DVT. Therefore, activation of the Wnt/ß-catenin signal may promote the formation of DVT in sepsis mice. CONCLUSIONS: LGK974 protects against DVT formation in sepsis mice by inhibiting the activation of the Wnt/ß-catenin signal and down-regulating the production of proinflammatory cytokines, PAI-1, and adhesion molecules. LGK974 may be a new candidate for the treatment of sepsis complicated with DVT.


Asunto(s)
Pirazinas , Piridinas , Sepsis , Trombosis de la Vena , Ratones , Animales , beta Catenina , Trombosis de la Vena/tratamiento farmacológico , Modelos Animales de Enfermedad , Inflamación , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , Colágeno/metabolismo
9.
Materials (Basel) ; 17(2)2024 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-38255464

RESUMEN

CFRP/Ti stacks composed of carbon fiber-reinforced plastic composites (CFRP) and titanium alloys (Ti) are widely used in aerospace fields. However, in the integrated hole-making process of CFRP/Ti stacks, the machining characteristics of various materials are significantly different, and constant machining parameters cannot simultaneously meet the high-quality machining requirements of two materials. In addition, errors exist between the actual thickness of each material layer and the theoretical value, which causes an impediment to the monitoring of the machining interface and the corresponding adjustment of parameters. An adaptive machining method for the helical milling of CFRP/Ti stacks based on interface identification is proposed in this paper. The machining characteristics of the pneumatic spindle and the interface state in the helical milling of CFRP/Ti stacks are analyzed using self-developed portable helical milling equipment, and a new algorithm for the real-time monitoring of the machining interface position and adaptive adjustment of the machining parameters according to the interface identification result is proposed. Helical milling experiments were carried out, the results show that the proposed method can effectively identify the position of the machining interface with good identification accuracy. Moreover, the proposed parameter-adaptive optimized machining method for CFRP/Ti stacks can significantly improve hole diameter accuracy and machining quality.

10.
Sci Bull (Beijing) ; 2024 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-39030103

RESUMEN

Exploiting the intelligent photocatalysts capable of phase separation provides a promising solution to the removal of uranium, which is expected to solve the difficulty in separation and the poor selectivity of traditional photocatalysts in carbonate-containing uranium wastewater. In this paper, the γ-FeOOH/konjac glucomannan grafted with phenolic hydroxyl groups/poly-N-isopropylacrylamide (γ-FeOOH/KGM(Ga)/PNIPAM) thermosensitive hydrogel is proposed as the photocatalysts for extracting uranium from carbonate-containing uranium wastewater. The dynamic phase transformation is demonstrated to confirm the arbitrary transition of γ-FeOOH/KGM(Ga)/PNIPAM thermosensitive hydrogel from a dispersed state with a high specific surface area at low temperatures to a stable aggregated state at high temperatures. Notably, the γ-FeOOH/KGM(Ga)/PNIPAM thermosensitive hydrogel achieves a remarkably high rate of 92.3% in the removal of uranium from the wastewater containing carbonates and maintains the efficiency of uranium removal from uranium mine wastewater at over 90%. Relying on electron spin resonance and free radical capture experiment, we reveal the adsorption-reduction-nucleation-crystallization mechanism of uranium on γ-FeOOH/KGM(Ga)/PNIPAM thermosensitive hydrogel. Overall, this strategy provides a promising solution to treating uranium-contaminated wastewater, showing a massive potential in water purification.

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