Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
2.
Carbohydr Polym ; 334: 122058, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38553243

RESUMEN

Global public health is seriously threatened by thrombotic disorders because of their high rates of mortality and disability. Most thrombolytic agents, especially protein-based pharmaceuticals, have a short half-life in circulation, reducing their effectiveness in thrombolysis. The creation of an intelligent drug delivery system that delivers medication precisely and releases it under regulated conditions at nearby thrombus sites is essential for effective thrombolysis. In this article, we present a unique medication delivery system (MCRUA) that selectively targets platelets and releases drugs by stimulation from the thrombus' microenvironment. The thrombolytic enzyme urokinase-type plasminogen-activator (uPA) and the anti-inflammatory medication Aspirin (acetylsalicylic acid, ASA) are both loaded onto pH-sensitive CaCO3/cyclodextrin crosslinking metal-organic frameworks (MC) that make up the MCRUA system. c(RGD) is functionalized on the surface of MC, which is functionalized by RGD to an esterification reaction. Additionally, the thrombus site's acidic microenvironment causes MCRUA to disintegrate to release uPA for thrombolysis and aiding in vessel recanalization. Moreover, cyclodextrin-encapsulated ASA enables the treatment of the inflammatory environment within the thrombus, enhancing the antiplatelet aggregation effects and promoting cooperative thrombolysis therapy. When used for thrombotic disorders, our drug delivery system (MCRUA) promotes thrombolysis, suppresses rethrombosis, and enhances biosafety with fewer hemorrhagic side effects.


Asunto(s)
Ciclodextrinas , Estructuras Metalorgánicas , Trombosis , Humanos , Terapia Trombolítica , Ciclodextrinas/uso terapéutico , Fibrinolíticos/farmacología , Fibrinolíticos/uso terapéutico , Activador de Plasminógeno de Tipo Uroquinasa/uso terapéutico , Trombosis/tratamiento farmacológico , Aspirina/farmacología , Oligopéptidos
3.
Carbohydr Polym ; 328: 121703, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38220339

RESUMEN

Arterial thrombosis is a critical thrombotic disease that poses a significant threat to human health. However, the existing clinical treatment of arterial thrombosis lacks effective targeting and precise drug release capability. In this study, we developed a system for targeted delivery and on-demand release in arterial thrombosis treatment. The carrier was constructed using chitosan (CS) and fucoidan (Fu) through layer-by-layer assembly, with subsequent surface modification using cRGD peptide. Upon encapsulation of urokinase-type plasminogen activator (uPA), the resulting therapeutic drug delivery system, uPA-CS/Fu@cRGD, demonstrated dual-targeting abilities towards P-selectin and αIIbß3, as well as pH and platelet-responsive release properties. Importantly, we have demonstrated that the dual targeting effect exhibits higher targeting efficiency at shear rates simulating thrombosed arterial conditions (1800 s-1) compared to single targeting for the first time. In the mouse common iliac artery model, uPA-CS/Fu@cRGD exhibited great thrombolytic capability while promoting the down-regulation of coagulation factors (FXa and PAI-1) and inflammatory factors (TNF-α and IL-6), thus improving the thrombus microenvironment and exerting potential in preventing re-occlusion. Our dual-target and dual-responsive, fucoidan-based macrovesicle represent a promising platform for advanced drug target delivery applications, with potential to prevent coagulation tendencies as well as improving thrombolytic and reducing the risk of re-occlusion.


Asunto(s)
Fibrinolíticos , Polisacáridos , Trombosis , Ratones , Animales , Humanos , Fibrinolíticos/farmacología , Fibrinolíticos/uso terapéutico , Fibrinolíticos/química , Fibrinólisis , Trombosis/tratamiento farmacológico , Terapia Trombolítica/métodos
4.
Mol Biol Evol ; 40(8)2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37494289

RESUMEN

Although the continual expansion of the brain during primate evolution accounts for our enhanced cognitive capabilities, the drivers of brain evolution have scarcely been explored in these ancestral nodes. Here, we performed large-scale comparative genomic, transcriptomic, and epigenomic analyses to investigate the evolutionary alterations acquired by brain genes and provide comprehensive listings of innovatory genetic elements along the evolutionary path from ancestral primates to human. The regulatory sequences associated with brain-expressed genes experienced rapid change, particularly in the ancestor of the Simiiformes. Extensive comparisons of single-cell and bulk transcriptomic data between primate and nonprimate brains revealed that these regulatory sequences may drive the high expression of certain genes in primate brains. Employing in utero electroporation into mouse embryonic cortex, we show that the primate-specific brain-biased gene BMP7 was recruited, probably in the ancestor of the Simiiformes, to regulate neuronal proliferation in the primate ventricular zone. Our study provides a comprehensive listing of genes and regulatory changes along the brain evolution lineage of ancestral primates leading to human. These data should be invaluable for future functional studies that will deepen our understanding not only of the genetic basis of human brain evolution but also of inherited disease.


Asunto(s)
Encéfalo , Primates , Ratones , Humanos , Animales , Primates/genética , Encéfalo/metabolismo , Evolución Molecular
5.
Int J Biol Macromol ; 247: 125852, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37460076

RESUMEN

Shark variable domain of new antigen receptors (VNARs) are the smallest naturally occurring binding domains with properties of low complexity, small size, cytoplasmic expression, and ease of engineering. Green fluorescent protein (GFP) molecules have been analyzed in conventional microscopy, but their spectral characteristics preclude their use in techniques offering substantially higher resolution. Besides, the GFP molecules can be quenched in acidic environment, which makes it necessary to develop anti-GFP antibody to solve these problems. In view of the diverse applications of GFP and unique physicochemical features of VNAR, the present study aims to generate VNARs against GFP. Here, we identified 36 VNARs targeting eCGP123, an extremely stable GFP, by phage display from three immunized sharks. These VNARs bound to eCGP123 with affinity constant KD values ranging from 6.76 to 605 nM. Among them, two lead VNARs named aGFP-14 and aGFP-15 with nanomolar eCGP123-binding affinity were selected for in-depth characterization. aGFP-14 and aGFP-15 recognized similar epitopes on eCGP123. X-ray crystallography studies clarified the mechanism by which aGFP14 interacts with eCGP123. aGFP-14 also showed cross-reaction with EGFP, with KD values of 47.2 nM. Finally, immunostaining analyses demonstrated that aGFP-14 was able to bind effectively to the EGFP expressed in both cultured cells and mouse brain tissues, and can be used as a fluorescence amplifier for EGFP. Our research demonstrates a feasible idea for the screening and production of shark-derived VNARs. The two high-affinity VNARs developed in the study contribute to the diversity of GFP sdAbs and may enhance the applications of GFP.


Asunto(s)
Tiburones , Anticuerpos de Dominio Único , Ratones , Animales , Proteínas Fluorescentes Verdes/genética , Epítopos , Proteínas Portadoras
6.
Front Plant Sci ; 12: 705021, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34795680

RESUMEN

Multi-target recognition and positioning using robots in orchards is a challenging task in modern precision agriculture owing to the presence of complex noise disturbance, including wind disturbance, changing illumination, and branch and leaf shading. To obtain the target information for a bud-cutting robotic operation, we employed a modified deep learning algorithm for the fast and precise recognition of banana fruits, inflorescence axes, and flower buds. Thus, the cutting point on the inflorescence axis was identified using an edge detection algorithm and geometric calculation. We proposed a modified YOLOv3 model based on clustering optimization and clarified the influence of front-lighting and backlighting on the model. Image segmentation and denoising were performed to obtain the edge images of the flower buds and inflorescence axes. The spatial geometry model was constructed on this basis. The center of symmetry and centroid were calculated for the edges of the flower buds. The equation for the position of the inflorescence axis was established, and the cutting point was determined. Experimental results showed that the modified YOLOv3 model based on clustering optimization showed excellent performance with good balance between speed and precision both under front-lighting and backlighting conditions. The total pixel positioning error between the calculated and manually determined optimal cutting point in the flower bud was 4 and 5 pixels under the front-lighting and backlighting conditions, respectively. The percentage of images that met the positioning requirements was 93 and 90%, respectively. The results indicate that the new method can satisfy the real-time operating requirements for the banana bud-cutting robot.

7.
Nat Commun ; 9(1): 4879, 2018 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-30451858

RESUMEN

Kainate-type glutamate receptors play critical roles in excitatory synaptic transmission and synaptic plasticity in the brain. GluK1 and GluK2 possess fundamentally different capabilities in surface trafficking as well as synaptic targeting in hippocampal CA1 neurons. Here we find that the excitatory postsynaptic currents (EPSCs) are significantly increased by the chimeric GluK1(SPGluK2) receptor, in which the signal peptide of GluK1 is replaced with that of GluK2. Coexpression of GluK1 signal peptide completely suppresses the gain in trafficking ability of GluK1(SPGluK2), indicating that the signal peptide represses receptor trafficking in a trans manner. Furthermore, we demonstrate that the signal peptide directly interacts with the amino-terminal domain (ATD) to inhibit the synaptic and surface expression of GluK1. Thus, we have uncovered a trafficking mechanism for kainate receptors and propose that the cleaved signal peptide behaves as a ligand of GluK1, through binding with the ATD, to repress forward trafficking of the receptor.


Asunto(s)
Región CA1 Hipocampal/metabolismo , Potenciales Postsinápticos Excitadores/fisiología , Señales de Clasificación de Proteína/genética , Receptores de Ácido Kaínico/metabolismo , Transmisión Sináptica/fisiología , Animales , Animales Recién Nacidos , Sitios de Unión , Región CA1 Hipocampal/citología , Expresión Génica , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Células HEK293 , Hemaglutininas/genética , Hemaglutininas/metabolismo , Humanos , Microtomía , Proteínas Mutantes Quiméricas/genética , Proteínas Mutantes Quiméricas/metabolismo , Plasticidad Neuronal , Técnicas de Cultivo de Órganos , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Ratas , Receptores de Ácido Kaínico/química , Receptores de Ácido Kaínico/genética , Sinapsis/metabolismo , Sinapsis/ultraestructura , Receptor de Ácido Kaínico GluK2
8.
Biochim Biophys Acta Mol Cell Res ; 1864(10): 1566-1577, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28583863

RESUMEN

Increasing circulating Ca2+ levels within the normal range has been reported to positively correlate with the incidence of fatal cardiovascular diseases (CVDs). However, limited studies have been able to delineate the potential mechanism(s) linking circulating Ca2+ to CVD. In this study, we exposed primary human umbilical vein endothelial cells (HUVECs) and human umbilical vein cell line (EA.hy926) to different extracellular Ca2+ to mimic the physiological state. Our data revealed that increasing extracellular Ca2+ significantly enhanced susceptibility to tumor necrosis factor (TNF)-alpha-stimulated vascular cell adhesion molecule (VCAM)-1 expression and monocytes adhesion. Knocking-down VCAM-1 by siRNA abolished calcium-induced monocytes adhesion on HUVECs. Follow up mechanistic investigations identified that extracellular Ca2+-increased calcium influx contributed to the activation of VCAM-1. This was mediated via upregulation of transient receptor potential channel (TRPC)1 in a nuclear factor (NF)κB-dependent manner. Most importantly, we found that a novel TRPC1-regulated extracellular signal-regulated kinase 1/2 (ERK1/2) pathway exclusively contributed to calcium-induced NFκB activation. This study provided direct evidence that increasing extracellular Ca2+ enhanced TNF-alpha-induced VCAM-1 activation and monocytes adhesion. Moreover, we identified a novel TRPC1/ERK1/2/NFκB signaling pathway mediating VCAM-1 activation and monocyte adhesion in this pathological process. Our studies indicate that blood calcium levels should be strictly monitored to help prevent CVD, and that TRPC1 might act as a potential target for the treatment and prevention against increased circulating calcium-enhanced CVDs.


Asunto(s)
Señalización del Calcio/genética , Enfermedades Cardiovasculares/metabolismo , Canales Catiónicos TRPC/genética , Factor de Necrosis Tumoral alfa/genética , Molécula 1 de Adhesión Celular Vascular/genética , Calcio/metabolismo , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/patología , Adhesión Celular/genética , Células Endoteliales de la Vena Umbilical Humana , Humanos , Sistema de Señalización de MAP Quinasas , Monocitos/metabolismo , Monocitos/patología , FN-kappa B/genética , FN-kappa B/metabolismo , Canales Catiónicos TRPC/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Molécula 1 de Adhesión Celular Vascular/metabolismo
9.
Cell Physiol Biochem ; 41(6): 2171-2182, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28441650

RESUMEN

BACKGROUND/AIMS: Atherosclerosis is a multifactorial chronic disease and is the main cause of death and impairment in the world. Endothelial injury and apoptosis play a crucial role in the onset and development of atherosclerosis. MicroRNAs (miRNAs) have been proven to be involved in the pathogenesis of atherosclerosis. However, studies of the functional role of apoptosis-related miRNAs in the endothelium during atherogenesis are limited. METHODS: Cell injury and apoptosis were measured in five types of cells transfected with miR-1185 or co-transfected with miR-1185 and its inhibitor. Bioinformatics analysis and a luciferase reporter assay were used to confirm the targets of miR-1185. The effects of the targets of miR-1185 on endothelial apoptosis were determined using small-interfering RNA. RESULTS: In this study, we first report that miR-1185 significantly promoted apoptosis in endothelial cells but not in vascular smooth muscle cells and macrophages. A mechanistic analysis showed that ultraviolet irradiation resistance-associated gene (UVRAG) and krev1 interaction trapped gene 1 (KRIT1), targets of miR-1185, mediated miR-1185-induced endothelial cell apoptosis. CONCLUSION: The results revealed the impact of miR-1185 on endothelial apoptosis, suggesting that miR-1185 may be a potential target for the prevention and treatment of atherosclerosis.


Asunto(s)
MicroARNs/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Regiones no Traducidas 3' , Antagomirs/metabolismo , Apoptosis , Aterosclerosis/metabolismo , Aterosclerosis/patología , Secuencia de Bases , Caspasa 3/metabolismo , Regulación hacia Abajo , Células Endoteliales de la Vena Umbilical Humana , Humanos , Proteína KRIT1 , MicroARNs/antagonistas & inhibidores , MicroARNs/genética , Proteínas Asociadas a Microtúbulos/antagonistas & inhibidores , Proteínas Asociadas a Microtúbulos/genética , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , Interferencia de ARN , ARN Interferente Pequeño/metabolismo , Alineación de Secuencia , Proteínas Supresoras de Tumor/antagonistas & inhibidores , Proteínas Supresoras de Tumor/genética , Regulación hacia Arriba
10.
Nutrients ; 8(4): 227, 2016 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-27104558

RESUMEN

The detrimental role of hepatic lipotoxicity has been well-implicated in the pathogenesis of NAFLD. Previously, we reported that inhibiting autophagy aggravated saturated fatty acid (SFA)-induced hepatotoxicity. Insulin, a physiological inhibitor of autophagy, is commonly increased within NAFLD mainly caused by insulin resistance. We therefore hypothesized that insulin augments the sensitivity of hepatocyte to SFA-induced lipotoxicity. The present study was conducted via employing human and mouse hepatocytes, which were exposed to SFAs, insulin, or their combination. Unexpectedly, our results indicated that insulin protected hepatocytes against SFA-induced lipotoxicity, based on the LDH, MTT, and nuclear morphological measurements, and the detection from cleaved-Parp-1 and -caspase-3 expressions. We subsequently clarified that insulin led to a rapid and short-period inhibition of autophagy, which was gradually recovered after 1 h incubation in hepatocytes, and such extent of inhibition was insufficient to aggravate SFA-induced lipotoxicity. The mechanistic study revealed that insulin-induced alleviation of ER stress contributed to its hepatoprotective role. Pre-treating hepatocytes with insulin significantly stimulated phosphorylated-Akt and reversed SFA-induced up-regulation of p53. Chemical inhibition of p53 by pifithrin-α robustly prevented palmitate-induced cell death. The PI3K/Akt pathway blockade by its special antagonist abolished the protective role of insulin against SFA-induced lipotoxicity and p53 up-regulation. Furthermore, we observed that insulin promoted intracellular TG deposits in hepatocytes in the present of palmitate. However, blocking TG accumulation via genetically silencing DGAT-2 did not prevent insulin-protected lipotoxicity. Our study demonstrated that insulin strongly protected against SFA-induced lipotoxicity in hepatocytes mechanistically through alleviating ER stress via a PI3K/Akt/p53 involved pathway but independently from autophagy.


Asunto(s)
Hepatocitos/efectos de los fármacos , Insulina/farmacología , Lípidos/toxicidad , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Animales , Regulación de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Hepatocitos/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ácido Palmítico/toxicidad , Fosfatidilinositol 3-Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/genética , Triglicéridos/metabolismo , Proteína p53 Supresora de Tumor/genética
11.
Mol Nutr Food Res ; 60(4): 798-809, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26694996

RESUMEN

SCOPE: Individuals deficient in vitamin D are more likely to have higher circulating cholesterol levels and cardiovascular diseases. However, the underlying mechanisms are still unclear. METHODS AND RESULTS: A cross-sectional survey, animal study, and in vitro experiments were conducted to investigate the effect and mechanisms of vitamin D deficiency on endogenous cholesterol metabolism. We demonstrated that vitamin D deficiency was positively associated with an increase of total serum cholesterol and low-density lipoprotein cholesterol levels in northern Chinese individuals. The vitamin D deficiency-induced increase of cholesterol concentration was mainly due to enhanced cholesterol biosynthesis rather than reduced catabolism. Under vitamin D deficiency, the transcriptional activity of vitamin D receptor (VDR) was decreased, leading to the downregulation of insulin-induced gene-2 (Insig-2) expression and thus its inhibitory role on sterol regulatory element-binding protein 2 activation; 3-hydroxy-3-methylglutaryl-coenzyme A reductase expression was accordingly increased. Vitamin D3 was protective against vitamin D deficiency-induced cholesterol increase by maintaining the transcriptional activity of VDR and Insig-2 expression. CONCLUSION: Vitamin D deficiency is associated with the increase of circulating cholesterol in the people of northern China by enhancing hepatic cholesterol biosynthesis, which was linked to the reduction of transcriptional activity of VDR.


Asunto(s)
Colesterol/sangre , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Proteínas de la Membrana/metabolismo , Receptores de Calcitriol/metabolismo , Proteína 2 de Unión a Elementos Reguladores de Esteroles/metabolismo , Deficiencia de Vitamina D/metabolismo , Adulto , Animales , Pueblo Asiatico , China , Colesterol/metabolismo , Estudios Transversales , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ratas Wistar , Vitamina D/sangre , Deficiencia de Vitamina D/sangre
12.
Wei Sheng Yan Jiu ; 37(4): 502-4, 2008 Jul.
Artículo en Chino | MEDLINE | ID: mdl-18839543

RESUMEN

OBJECTIVE: To investigate the effects of Nano-Selenium on learning memory capability and activity of two kinds of Se-protein in brain and liver of mice, Na, SeO3 as the controls. METHODS: The mice were administred two kinds of origin (doses of 1 microgSe/d, 2 microgSe/d, 4 microgSe/d) Se by intra-gastric injection respectively. The learning memory ability of the mice was measured by Y-type maze test. Activities of glutathione peroxidase (GSH-Px) and iodothyronine deiodinase (ID) in brain and liver were also measured. RESULTS: In comparison with the control groups of Na2 Se03, learning memory abilities were improved and activities of ID and GSH-Px (P < 0.01 or P < 0.05) of brain and liver were increased in Nano-Se treatment groups. CONCLUSION: Nano-Se could improve learning memory ability of mice, and enhance ID and GSH-Px activities of brain and liver in mice.


Asunto(s)
Glutatión Peroxidasa/metabolismo , Aprendizaje por Laberinto/efectos de los fármacos , Memoria/efectos de los fármacos , Nanopartículas del Metal , Selenio/farmacología , Animales , Encéfalo/enzimología , Femenino , Glutatión Peroxidasa/efectos de los fármacos , Yoduro Peroxidasa/efectos de los fármacos , Yoduro Peroxidasa/metabolismo , Hígado/enzimología , Masculino , Ratones , Distribución Aleatoria , Selenio/administración & dosificación
13.
Ecotoxicol Environ Saf ; 71(3): 677-84, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18261795

RESUMEN

The agricultural application of rare-earth elements (REEs) would promote REEs inevitably to enter in the environment and then to threaten the environmental safety and human health. Therefore, the distribution of the REEs ion, (141)Ce(III) and effects of La(III), Ce(III) and Tb(III) on the distribution of horseradish peroxidase (HRP) in horseradish mesophyll cells were investigated with electron microscopic radioautography and transmission electron microscopic cytochemistry. It was found for the first time that REEs ions can enter into the mesophyll cells, deposit in both extra and intra-cellular. Compared to the normal condition, after the horseradish leaves treated with La(III) or Tb(III), HRP located on the tonoplast is decreased and HRP is mainly located on the cell wall, while HRP is mainly located on the plasma membrane after the horseradish leaves were treated with Ce(III). This also indicated that REEs ions may regulate the plant growth through changing the distribution of enzymes.


Asunto(s)
Armoracia/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Peroxidasa de Rábano Silvestre/metabolismo , Metales de Tierras Raras/toxicidad , Fracciones Subcelulares/metabolismo , Armoracia/metabolismo , Armoracia/ultraestructura , Membrana Celular/metabolismo , Pared Celular/efectos de los fármacos , Pared Celular/metabolismo , Pared Celular/ultraestructura , Cerio/metabolismo , Cerio/toxicidad , Contaminantes Ambientales/metabolismo , Humanos , Lantano/metabolismo , Lantano/toxicidad , Células del Mesófilo/efectos de los fármacos , Células del Mesófilo/metabolismo , Células del Mesófilo/ultraestructura , Metales de Tierras Raras/metabolismo , Microscopía Electrónica de Transmisión , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Hojas de la Planta/ultraestructura , Terbio/metabolismo , Terbio/toxicidad
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...